T: quilt http://people.redhat.com/agk/patches/linux/editing/
S: Maintained
F: Documentation/device-mapper/
+F: drivers/md/Makefile
+F: drivers/md/Kconfig
F: drivers/md/dm*
F: drivers/md/persistent-data/
F: include/linux/device-mapper.h
L: linux-raid@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/shli/md.git
S: Supported
-F: drivers/md/
+F: drivers/md/Makefile
+F: drivers/md/Kconfig
+F: drivers/md/md*
+F: drivers/md/raid*
F: include/linux/raid/
F: include/uapi/linux/raid/
dm-cache-smq-y += dm-cache-policy-smq.o
dm-era-y += dm-era-target.o
dm-verity-y += dm-verity-target.o
-md-mod-y += md.o bitmap.o
+md-mod-y += md.o md-bitmap.o
raid456-y += raid5.o raid5-cache.o raid5-ppl.o
dm-zoned-y += dm-zoned-target.o dm-zoned-metadata.o dm-zoned-reclaim.o
+linear-y += md-linear.o
+multipath-y += md-multipath.o
+faulty-y += md-faulty.o
# Note: link order is important. All raid personalities
# and must come before md.o, as they each initialise
+++ /dev/null
-/*
- * bitmap.c two-level bitmap (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
- *
- * bitmap_create - sets up the bitmap structure
- * bitmap_destroy - destroys the bitmap structure
- *
- * additions, Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.:
- * - added disk storage for bitmap
- * - changes to allow various bitmap chunk sizes
- */
-
-/*
- * Still to do:
- *
- * flush after percent set rather than just time based. (maybe both).
- */
-
-#include <linux/blkdev.h>
-#include <linux/module.h>
-#include <linux/errno.h>
-#include <linux/slab.h>
-#include <linux/init.h>
-#include <linux/timer.h>
-#include <linux/sched.h>
-#include <linux/list.h>
-#include <linux/file.h>
-#include <linux/mount.h>
-#include <linux/buffer_head.h>
-#include <linux/seq_file.h>
-#include <trace/events/block.h>
-#include "md.h"
-#include "bitmap.h"
-
-static inline char *bmname(struct bitmap *bitmap)
-{
- return bitmap->mddev ? mdname(bitmap->mddev) : "mdX";
-}
-
-/*
- * check a page and, if necessary, allocate it (or hijack it if the alloc fails)
- *
- * 1) check to see if this page is allocated, if it's not then try to alloc
- * 2) if the alloc fails, set the page's hijacked flag so we'll use the
- * page pointer directly as a counter
- *
- * if we find our page, we increment the page's refcount so that it stays
- * allocated while we're using it
- */
-static int bitmap_checkpage(struct bitmap_counts *bitmap,
- unsigned long page, int create, int no_hijack)
-__releases(bitmap->lock)
-__acquires(bitmap->lock)
-{
- unsigned char *mappage;
-
- if (page >= bitmap->pages) {
- /* This can happen if bitmap_start_sync goes beyond
- * End-of-device while looking for a whole page.
- * It is harmless.
- */
- return -EINVAL;
- }
-
- if (bitmap->bp[page].hijacked) /* it's hijacked, don't try to alloc */
- return 0;
-
- if (bitmap->bp[page].map) /* page is already allocated, just return */
- return 0;
-
- if (!create)
- return -ENOENT;
-
- /* this page has not been allocated yet */
-
- spin_unlock_irq(&bitmap->lock);
- /* It is possible that this is being called inside a
- * prepare_to_wait/finish_wait loop from raid5c:make_request().
- * In general it is not permitted to sleep in that context as it
- * can cause the loop to spin freely.
- * That doesn't apply here as we can only reach this point
- * once with any loop.
- * When this function completes, either bp[page].map or
- * bp[page].hijacked. In either case, this function will
- * abort before getting to this point again. So there is
- * no risk of a free-spin, and so it is safe to assert
- * that sleeping here is allowed.
- */
- sched_annotate_sleep();
- mappage = kzalloc(PAGE_SIZE, GFP_NOIO);
- spin_lock_irq(&bitmap->lock);
-
- if (mappage == NULL) {
- pr_debug("md/bitmap: map page allocation failed, hijacking\n");
- /* We don't support hijack for cluster raid */
- if (no_hijack)
- return -ENOMEM;
- /* failed - set the hijacked flag so that we can use the
- * pointer as a counter */
- if (!bitmap->bp[page].map)
- bitmap->bp[page].hijacked = 1;
- } else if (bitmap->bp[page].map ||
- bitmap->bp[page].hijacked) {
- /* somebody beat us to getting the page */
- kfree(mappage);
- } else {
-
- /* no page was in place and we have one, so install it */
-
- bitmap->bp[page].map = mappage;
- bitmap->missing_pages--;
- }
- return 0;
-}
-
-/* if page is completely empty, put it back on the free list, or dealloc it */
-/* if page was hijacked, unmark the flag so it might get alloced next time */
-/* Note: lock should be held when calling this */
-static void bitmap_checkfree(struct bitmap_counts *bitmap, unsigned long page)
-{
- char *ptr;
-
- if (bitmap->bp[page].count) /* page is still busy */
- return;
-
- /* page is no longer in use, it can be released */
-
- if (bitmap->bp[page].hijacked) { /* page was hijacked, undo this now */
- bitmap->bp[page].hijacked = 0;
- bitmap->bp[page].map = NULL;
- } else {
- /* normal case, free the page */
- ptr = bitmap->bp[page].map;
- bitmap->bp[page].map = NULL;
- bitmap->missing_pages++;
- kfree(ptr);
- }
-}
-
-/*
- * bitmap file handling - read and write the bitmap file and its superblock
- */
-
-/*
- * basic page I/O operations
- */
-
-/* IO operations when bitmap is stored near all superblocks */
-static int read_sb_page(struct mddev *mddev, loff_t offset,
- struct page *page,
- unsigned long index, int size)
-{
- /* choose a good rdev and read the page from there */
-
- struct md_rdev *rdev;
- sector_t target;
-
- rdev_for_each(rdev, mddev) {
- if (! test_bit(In_sync, &rdev->flags)
- || test_bit(Faulty, &rdev->flags)
- || test_bit(Bitmap_sync, &rdev->flags))
- continue;
-
- target = offset + index * (PAGE_SIZE/512);
-
- if (sync_page_io(rdev, target,
- roundup(size, bdev_logical_block_size(rdev->bdev)),
- page, REQ_OP_READ, 0, true)) {
- page->index = index;
- return 0;
- }
- }
- return -EIO;
-}
-
-static struct md_rdev *next_active_rdev(struct md_rdev *rdev, struct mddev *mddev)
-{
- /* Iterate the disks of an mddev, using rcu to protect access to the
- * linked list, and raising the refcount of devices we return to ensure
- * they don't disappear while in use.
- * As devices are only added or removed when raid_disk is < 0 and
- * nr_pending is 0 and In_sync is clear, the entries we return will
- * still be in the same position on the list when we re-enter
- * list_for_each_entry_continue_rcu.
- *
- * Note that if entered with 'rdev == NULL' to start at the
- * beginning, we temporarily assign 'rdev' to an address which
- * isn't really an rdev, but which can be used by
- * list_for_each_entry_continue_rcu() to find the first entry.
- */
- rcu_read_lock();
- if (rdev == NULL)
- /* start at the beginning */
- rdev = list_entry(&mddev->disks, struct md_rdev, same_set);
- else {
- /* release the previous rdev and start from there. */
- rdev_dec_pending(rdev, mddev);
- }
- list_for_each_entry_continue_rcu(rdev, &mddev->disks, same_set) {
- if (rdev->raid_disk >= 0 &&
- !test_bit(Faulty, &rdev->flags)) {
- /* this is a usable devices */
- atomic_inc(&rdev->nr_pending);
- rcu_read_unlock();
- return rdev;
- }
- }
- rcu_read_unlock();
- return NULL;
-}
-
-static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
-{
- struct md_rdev *rdev;
- struct block_device *bdev;
- struct mddev *mddev = bitmap->mddev;
- struct bitmap_storage *store = &bitmap->storage;
-
-restart:
- rdev = NULL;
- while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
- int size = PAGE_SIZE;
- loff_t offset = mddev->bitmap_info.offset;
-
- bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
-
- if (page->index == store->file_pages-1) {
- int last_page_size = store->bytes & (PAGE_SIZE-1);
- if (last_page_size == 0)
- last_page_size = PAGE_SIZE;
- size = roundup(last_page_size,
- bdev_logical_block_size(bdev));
- }
- /* Just make sure we aren't corrupting data or
- * metadata
- */
- if (mddev->external) {
- /* Bitmap could be anywhere. */
- if (rdev->sb_start + offset + (page->index
- * (PAGE_SIZE/512))
- > rdev->data_offset
- &&
- rdev->sb_start + offset
- < (rdev->data_offset + mddev->dev_sectors
- + (PAGE_SIZE/512)))
- goto bad_alignment;
- } else if (offset < 0) {
- /* DATA BITMAP METADATA */
- if (offset
- + (long)(page->index * (PAGE_SIZE/512))
- + size/512 > 0)
- /* bitmap runs in to metadata */
- goto bad_alignment;
- if (rdev->data_offset + mddev->dev_sectors
- > rdev->sb_start + offset)
- /* data runs in to bitmap */
- goto bad_alignment;
- } else if (rdev->sb_start < rdev->data_offset) {
- /* METADATA BITMAP DATA */
- if (rdev->sb_start
- + offset
- + page->index*(PAGE_SIZE/512) + size/512
- > rdev->data_offset)
- /* bitmap runs in to data */
- goto bad_alignment;
- } else {
- /* DATA METADATA BITMAP - no problems */
- }
- md_super_write(mddev, rdev,
- rdev->sb_start + offset
- + page->index * (PAGE_SIZE/512),
- size,
- page);
- }
-
- if (wait && md_super_wait(mddev) < 0)
- goto restart;
- return 0;
-
- bad_alignment:
- return -EINVAL;
-}
-
-static void bitmap_file_kick(struct bitmap *bitmap);
-/*
- * write out a page to a file
- */
-static void write_page(struct bitmap *bitmap, struct page *page, int wait)
-{
- struct buffer_head *bh;
-
- if (bitmap->storage.file == NULL) {
- switch (write_sb_page(bitmap, page, wait)) {
- case -EINVAL:
- set_bit(BITMAP_WRITE_ERROR, &bitmap->flags);
- }
- } else {
-
- bh = page_buffers(page);
-
- while (bh && bh->b_blocknr) {
- atomic_inc(&bitmap->pending_writes);
- set_buffer_locked(bh);
- set_buffer_mapped(bh);
- submit_bh(REQ_OP_WRITE, REQ_SYNC, bh);
- bh = bh->b_this_page;
- }
-
- if (wait)
- wait_event(bitmap->write_wait,
- atomic_read(&bitmap->pending_writes)==0);
- }
- if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
- bitmap_file_kick(bitmap);
-}
-
-static void end_bitmap_write(struct buffer_head *bh, int uptodate)
-{
- struct bitmap *bitmap = bh->b_private;
-
- if (!uptodate)
- set_bit(BITMAP_WRITE_ERROR, &bitmap->flags);
- if (atomic_dec_and_test(&bitmap->pending_writes))
- wake_up(&bitmap->write_wait);
-}
-
-/* copied from buffer.c */
-static void
-__clear_page_buffers(struct page *page)
-{
- ClearPagePrivate(page);
- set_page_private(page, 0);
- put_page(page);
-}
-static void free_buffers(struct page *page)
-{
- struct buffer_head *bh;
-
- if (!PagePrivate(page))
- return;
-
- bh = page_buffers(page);
- while (bh) {
- struct buffer_head *next = bh->b_this_page;
- free_buffer_head(bh);
- bh = next;
- }
- __clear_page_buffers(page);
- put_page(page);
-}
-
-/* read a page from a file.
- * We both read the page, and attach buffers to the page to record the
- * address of each block (using bmap). These addresses will be used
- * to write the block later, completely bypassing the filesystem.
- * This usage is similar to how swap files are handled, and allows us
- * to write to a file with no concerns of memory allocation failing.
- */
-static int read_page(struct file *file, unsigned long index,
- struct bitmap *bitmap,
- unsigned long count,
- struct page *page)
-{
- int ret = 0;
- struct inode *inode = file_inode(file);
- struct buffer_head *bh;
- sector_t block;
-
- pr_debug("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE,
- (unsigned long long)index << PAGE_SHIFT);
-
- bh = alloc_page_buffers(page, 1<<inode->i_blkbits, 0);
- if (!bh) {
- ret = -ENOMEM;
- goto out;
- }
- attach_page_buffers(page, bh);
- block = index << (PAGE_SHIFT - inode->i_blkbits);
- while (bh) {
- if (count == 0)
- bh->b_blocknr = 0;
- else {
- bh->b_blocknr = bmap(inode, block);
- if (bh->b_blocknr == 0) {
- /* Cannot use this file! */
- ret = -EINVAL;
- goto out;
- }
- bh->b_bdev = inode->i_sb->s_bdev;
- if (count < (1<<inode->i_blkbits))
- count = 0;
- else
- count -= (1<<inode->i_blkbits);
-
- bh->b_end_io = end_bitmap_write;
- bh->b_private = bitmap;
- atomic_inc(&bitmap->pending_writes);
- set_buffer_locked(bh);
- set_buffer_mapped(bh);
- submit_bh(REQ_OP_READ, 0, bh);
- }
- block++;
- bh = bh->b_this_page;
- }
- page->index = index;
-
- wait_event(bitmap->write_wait,
- atomic_read(&bitmap->pending_writes)==0);
- if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
- ret = -EIO;
-out:
- if (ret)
- pr_err("md: bitmap read error: (%dB @ %llu): %d\n",
- (int)PAGE_SIZE,
- (unsigned long long)index << PAGE_SHIFT,
- ret);
- return ret;
-}
-
-/*
- * bitmap file superblock operations
- */
-
-/*
- * bitmap_wait_writes() should be called before writing any bitmap
- * blocks, to ensure previous writes, particularly from
- * bitmap_daemon_work(), have completed.
- */
-static void bitmap_wait_writes(struct bitmap *bitmap)
-{
- if (bitmap->storage.file)
- wait_event(bitmap->write_wait,
- atomic_read(&bitmap->pending_writes)==0);
- else
- /* Note that we ignore the return value. The writes
- * might have failed, but that would just mean that
- * some bits which should be cleared haven't been,
- * which is safe. The relevant bitmap blocks will
- * probably get written again, but there is no great
- * loss if they aren't.
- */
- md_super_wait(bitmap->mddev);
-}
-
-
-/* update the event counter and sync the superblock to disk */
-void bitmap_update_sb(struct bitmap *bitmap)
-{
- bitmap_super_t *sb;
-
- if (!bitmap || !bitmap->mddev) /* no bitmap for this array */
- return;
- if (bitmap->mddev->bitmap_info.external)
- return;
- if (!bitmap->storage.sb_page) /* no superblock */
- return;
- sb = kmap_atomic(bitmap->storage.sb_page);
- sb->events = cpu_to_le64(bitmap->mddev->events);
- if (bitmap->mddev->events < bitmap->events_cleared)
- /* rocking back to read-only */
- bitmap->events_cleared = bitmap->mddev->events;
- sb->events_cleared = cpu_to_le64(bitmap->events_cleared);
- sb->state = cpu_to_le32(bitmap->flags);
- /* Just in case these have been changed via sysfs: */
- sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ);
- sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind);
- /* This might have been changed by a reshape */
- sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
- sb->chunksize = cpu_to_le32(bitmap->mddev->bitmap_info.chunksize);
- sb->nodes = cpu_to_le32(bitmap->mddev->bitmap_info.nodes);
- sb->sectors_reserved = cpu_to_le32(bitmap->mddev->
- bitmap_info.space);
- kunmap_atomic(sb);
- write_page(bitmap, bitmap->storage.sb_page, 1);
-}
-EXPORT_SYMBOL(bitmap_update_sb);
-
-/* print out the bitmap file superblock */
-void bitmap_print_sb(struct bitmap *bitmap)
-{
- bitmap_super_t *sb;
-
- if (!bitmap || !bitmap->storage.sb_page)
- return;
- sb = kmap_atomic(bitmap->storage.sb_page);
- pr_debug("%s: bitmap file superblock:\n", bmname(bitmap));
- pr_debug(" magic: %08x\n", le32_to_cpu(sb->magic));
- pr_debug(" version: %d\n", le32_to_cpu(sb->version));
- pr_debug(" uuid: %08x.%08x.%08x.%08x\n",
- le32_to_cpu(*(__u32 *)(sb->uuid+0)),
- le32_to_cpu(*(__u32 *)(sb->uuid+4)),
- le32_to_cpu(*(__u32 *)(sb->uuid+8)),
- le32_to_cpu(*(__u32 *)(sb->uuid+12)));
- pr_debug(" events: %llu\n",
- (unsigned long long) le64_to_cpu(sb->events));
- pr_debug("events cleared: %llu\n",
- (unsigned long long) le64_to_cpu(sb->events_cleared));
- pr_debug(" state: %08x\n", le32_to_cpu(sb->state));
- pr_debug(" chunksize: %d B\n", le32_to_cpu(sb->chunksize));
- pr_debug(" daemon sleep: %ds\n", le32_to_cpu(sb->daemon_sleep));
- pr_debug(" sync size: %llu KB\n",
- (unsigned long long)le64_to_cpu(sb->sync_size)/2);
- pr_debug("max write behind: %d\n", le32_to_cpu(sb->write_behind));
- kunmap_atomic(sb);
-}
-
-/*
- * bitmap_new_disk_sb
- * @bitmap
- *
- * This function is somewhat the reverse of bitmap_read_sb. bitmap_read_sb
- * reads and verifies the on-disk bitmap superblock and populates bitmap_info.
- * This function verifies 'bitmap_info' and populates the on-disk bitmap
- * structure, which is to be written to disk.
- *
- * Returns: 0 on success, -Exxx on error
- */
-static int bitmap_new_disk_sb(struct bitmap *bitmap)
-{
- bitmap_super_t *sb;
- unsigned long chunksize, daemon_sleep, write_behind;
-
- bitmap->storage.sb_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
- if (bitmap->storage.sb_page == NULL)
- return -ENOMEM;
- bitmap->storage.sb_page->index = 0;
-
- sb = kmap_atomic(bitmap->storage.sb_page);
-
- sb->magic = cpu_to_le32(BITMAP_MAGIC);
- sb->version = cpu_to_le32(BITMAP_MAJOR_HI);
-
- chunksize = bitmap->mddev->bitmap_info.chunksize;
- BUG_ON(!chunksize);
- if (!is_power_of_2(chunksize)) {
- kunmap_atomic(sb);
- pr_warn("bitmap chunksize not a power of 2\n");
- return -EINVAL;
- }
- sb->chunksize = cpu_to_le32(chunksize);
-
- daemon_sleep = bitmap->mddev->bitmap_info.daemon_sleep;
- if (!daemon_sleep || (daemon_sleep > MAX_SCHEDULE_TIMEOUT)) {
- pr_debug("Choosing daemon_sleep default (5 sec)\n");
- daemon_sleep = 5 * HZ;
- }
- sb->daemon_sleep = cpu_to_le32(daemon_sleep);
- bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
-
- /*
- * FIXME: write_behind for RAID1. If not specified, what
- * is a good choice? We choose COUNTER_MAX / 2 arbitrarily.
- */
- write_behind = bitmap->mddev->bitmap_info.max_write_behind;
- if (write_behind > COUNTER_MAX)
- write_behind = COUNTER_MAX / 2;
- sb->write_behind = cpu_to_le32(write_behind);
- bitmap->mddev->bitmap_info.max_write_behind = write_behind;
-
- /* keep the array size field of the bitmap superblock up to date */
- sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
-
- memcpy(sb->uuid, bitmap->mddev->uuid, 16);
-
- set_bit(BITMAP_STALE, &bitmap->flags);
- sb->state = cpu_to_le32(bitmap->flags);
- bitmap->events_cleared = bitmap->mddev->events;
- sb->events_cleared = cpu_to_le64(bitmap->mddev->events);
- bitmap->mddev->bitmap_info.nodes = 0;
-
- kunmap_atomic(sb);
-
- return 0;
-}
-
-/* read the superblock from the bitmap file and initialize some bitmap fields */
-static int bitmap_read_sb(struct bitmap *bitmap)
-{
- char *reason = NULL;
- bitmap_super_t *sb;
- unsigned long chunksize, daemon_sleep, write_behind;
- unsigned long long events;
- int nodes = 0;
- unsigned long sectors_reserved = 0;
- int err = -EINVAL;
- struct page *sb_page;
- loff_t offset = bitmap->mddev->bitmap_info.offset;
-
- if (!bitmap->storage.file && !bitmap->mddev->bitmap_info.offset) {
- chunksize = 128 * 1024 * 1024;
- daemon_sleep = 5 * HZ;
- write_behind = 0;
- set_bit(BITMAP_STALE, &bitmap->flags);
- err = 0;
- goto out_no_sb;
- }
- /* page 0 is the superblock, read it... */
- sb_page = alloc_page(GFP_KERNEL);
- if (!sb_page)
- return -ENOMEM;
- bitmap->storage.sb_page = sb_page;
-
-re_read:
- /* If cluster_slot is set, the cluster is setup */
- if (bitmap->cluster_slot >= 0) {
- sector_t bm_blocks = bitmap->mddev->resync_max_sectors;
-
- sector_div(bm_blocks,
- bitmap->mddev->bitmap_info.chunksize >> 9);
- /* bits to bytes */
- bm_blocks = ((bm_blocks+7) >> 3) + sizeof(bitmap_super_t);
- /* to 4k blocks */
- bm_blocks = DIV_ROUND_UP_SECTOR_T(bm_blocks, 4096);
- offset = bitmap->mddev->bitmap_info.offset + (bitmap->cluster_slot * (bm_blocks << 3));
- pr_debug("%s:%d bm slot: %d offset: %llu\n", __func__, __LINE__,
- bitmap->cluster_slot, offset);
- }
-
- if (bitmap->storage.file) {
- loff_t isize = i_size_read(bitmap->storage.file->f_mapping->host);
- int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize;
-
- err = read_page(bitmap->storage.file, 0,
- bitmap, bytes, sb_page);
- } else {
- err = read_sb_page(bitmap->mddev,
- offset,
- sb_page,
- 0, sizeof(bitmap_super_t));
- }
- if (err)
- return err;
-
- err = -EINVAL;
- sb = kmap_atomic(sb_page);
-
- chunksize = le32_to_cpu(sb->chunksize);
- daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
- write_behind = le32_to_cpu(sb->write_behind);
- sectors_reserved = le32_to_cpu(sb->sectors_reserved);
- /* Setup nodes/clustername only if bitmap version is
- * cluster-compatible
- */
- if (sb->version == cpu_to_le32(BITMAP_MAJOR_CLUSTERED)) {
- nodes = le32_to_cpu(sb->nodes);
- strlcpy(bitmap->mddev->bitmap_info.cluster_name,
- sb->cluster_name, 64);
- }
-
- /* verify that the bitmap-specific fields are valid */
- if (sb->magic != cpu_to_le32(BITMAP_MAGIC))
- reason = "bad magic";
- else if (le32_to_cpu(sb->version) < BITMAP_MAJOR_LO ||
- le32_to_cpu(sb->version) > BITMAP_MAJOR_CLUSTERED)
- reason = "unrecognized superblock version";
- else if (chunksize < 512)
- reason = "bitmap chunksize too small";
- else if (!is_power_of_2(chunksize))
- reason = "bitmap chunksize not a power of 2";
- else if (daemon_sleep < 1 || daemon_sleep > MAX_SCHEDULE_TIMEOUT)
- reason = "daemon sleep period out of range";
- else if (write_behind > COUNTER_MAX)
- reason = "write-behind limit out of range (0 - 16383)";
- if (reason) {
- pr_warn("%s: invalid bitmap file superblock: %s\n",
- bmname(bitmap), reason);
- goto out;
- }
-
- /* keep the array size field of the bitmap superblock up to date */
- sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
-
- if (bitmap->mddev->persistent) {
- /*
- * We have a persistent array superblock, so compare the
- * bitmap's UUID and event counter to the mddev's
- */
- if (memcmp(sb->uuid, bitmap->mddev->uuid, 16)) {
- pr_warn("%s: bitmap superblock UUID mismatch\n",
- bmname(bitmap));
- goto out;
- }
- events = le64_to_cpu(sb->events);
- if (!nodes && (events < bitmap->mddev->events)) {
- pr_warn("%s: bitmap file is out of date (%llu < %llu) -- forcing full recovery\n",
- bmname(bitmap), events,
- (unsigned long long) bitmap->mddev->events);
- set_bit(BITMAP_STALE, &bitmap->flags);
- }
- }
-
- /* assign fields using values from superblock */
- bitmap->flags |= le32_to_cpu(sb->state);
- if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN)
- set_bit(BITMAP_HOSTENDIAN, &bitmap->flags);
- bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
- strlcpy(bitmap->mddev->bitmap_info.cluster_name, sb->cluster_name, 64);
- err = 0;
-
-out:
- kunmap_atomic(sb);
- /* Assigning chunksize is required for "re_read" */
- bitmap->mddev->bitmap_info.chunksize = chunksize;
- if (err == 0 && nodes && (bitmap->cluster_slot < 0)) {
- err = md_setup_cluster(bitmap->mddev, nodes);
- if (err) {
- pr_warn("%s: Could not setup cluster service (%d)\n",
- bmname(bitmap), err);
- goto out_no_sb;
- }
- bitmap->cluster_slot = md_cluster_ops->slot_number(bitmap->mddev);
- goto re_read;
- }
-
-
-out_no_sb:
- if (test_bit(BITMAP_STALE, &bitmap->flags))
- bitmap->events_cleared = bitmap->mddev->events;
- bitmap->mddev->bitmap_info.chunksize = chunksize;
- bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
- bitmap->mddev->bitmap_info.max_write_behind = write_behind;
- bitmap->mddev->bitmap_info.nodes = nodes;
- if (bitmap->mddev->bitmap_info.space == 0 ||
- bitmap->mddev->bitmap_info.space > sectors_reserved)
- bitmap->mddev->bitmap_info.space = sectors_reserved;
- if (err) {
- bitmap_print_sb(bitmap);
- if (bitmap->cluster_slot < 0)
- md_cluster_stop(bitmap->mddev);
- }
- return err;
-}
-
-/*
- * general bitmap file operations
- */
-
-/*
- * on-disk bitmap:
- *
- * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
- * file a page at a time. There's a superblock at the start of the file.
- */
-/* calculate the index of the page that contains this bit */
-static inline unsigned long file_page_index(struct bitmap_storage *store,
- unsigned long chunk)
-{
- if (store->sb_page)
- chunk += sizeof(bitmap_super_t) << 3;
- return chunk >> PAGE_BIT_SHIFT;
-}
-
-/* calculate the (bit) offset of this bit within a page */
-static inline unsigned long file_page_offset(struct bitmap_storage *store,
- unsigned long chunk)
-{
- if (store->sb_page)
- chunk += sizeof(bitmap_super_t) << 3;
- return chunk & (PAGE_BITS - 1);
-}
-
-/*
- * return a pointer to the page in the filemap that contains the given bit
- *
- */
-static inline struct page *filemap_get_page(struct bitmap_storage *store,
- unsigned long chunk)
-{
- if (file_page_index(store, chunk) >= store->file_pages)
- return NULL;
- return store->filemap[file_page_index(store, chunk)];
-}
-
-static int bitmap_storage_alloc(struct bitmap_storage *store,
- unsigned long chunks, int with_super,
- int slot_number)
-{
- int pnum, offset = 0;
- unsigned long num_pages;
- unsigned long bytes;
-
- bytes = DIV_ROUND_UP(chunks, 8);
- if (with_super)
- bytes += sizeof(bitmap_super_t);
-
- num_pages = DIV_ROUND_UP(bytes, PAGE_SIZE);
- offset = slot_number * num_pages;
-
- store->filemap = kmalloc(sizeof(struct page *)
- * num_pages, GFP_KERNEL);
- if (!store->filemap)
- return -ENOMEM;
-
- if (with_super && !store->sb_page) {
- store->sb_page = alloc_page(GFP_KERNEL|__GFP_ZERO);
- if (store->sb_page == NULL)
- return -ENOMEM;
- }
-
- pnum = 0;
- if (store->sb_page) {
- store->filemap[0] = store->sb_page;
- pnum = 1;
- store->sb_page->index = offset;
- }
-
- for ( ; pnum < num_pages; pnum++) {
- store->filemap[pnum] = alloc_page(GFP_KERNEL|__GFP_ZERO);
- if (!store->filemap[pnum]) {
- store->file_pages = pnum;
- return -ENOMEM;
- }
- store->filemap[pnum]->index = pnum + offset;
- }
- store->file_pages = pnum;
-
- /* We need 4 bits per page, rounded up to a multiple
- * of sizeof(unsigned long) */
- store->filemap_attr = kzalloc(
- roundup(DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
- GFP_KERNEL);
- if (!store->filemap_attr)
- return -ENOMEM;
-
- store->bytes = bytes;
-
- return 0;
-}
-
-static void bitmap_file_unmap(struct bitmap_storage *store)
-{
- struct page **map, *sb_page;
- int pages;
- struct file *file;
-
- file = store->file;
- map = store->filemap;
- pages = store->file_pages;
- sb_page = store->sb_page;
-
- while (pages--)
- if (map[pages] != sb_page) /* 0 is sb_page, release it below */
- free_buffers(map[pages]);
- kfree(map);
- kfree(store->filemap_attr);
-
- if (sb_page)
- free_buffers(sb_page);
-
- if (file) {
- struct inode *inode = file_inode(file);
- invalidate_mapping_pages(inode->i_mapping, 0, -1);
- fput(file);
- }
-}
-
-/*
- * bitmap_file_kick - if an error occurs while manipulating the bitmap file
- * then it is no longer reliable, so we stop using it and we mark the file
- * as failed in the superblock
- */
-static void bitmap_file_kick(struct bitmap *bitmap)
-{
- char *path, *ptr = NULL;
-
- if (!test_and_set_bit(BITMAP_STALE, &bitmap->flags)) {
- bitmap_update_sb(bitmap);
-
- if (bitmap->storage.file) {
- path = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (path)
- ptr = file_path(bitmap->storage.file,
- path, PAGE_SIZE);
-
- pr_warn("%s: kicking failed bitmap file %s from array!\n",
- bmname(bitmap), IS_ERR(ptr) ? "" : ptr);
-
- kfree(path);
- } else
- pr_warn("%s: disabling internal bitmap due to errors\n",
- bmname(bitmap));
- }
-}
-
-enum bitmap_page_attr {
- BITMAP_PAGE_DIRTY = 0, /* there are set bits that need to be synced */
- BITMAP_PAGE_PENDING = 1, /* there are bits that are being cleaned.
- * i.e. counter is 1 or 2. */
- BITMAP_PAGE_NEEDWRITE = 2, /* there are cleared bits that need to be synced */
-};
-
-static inline void set_page_attr(struct bitmap *bitmap, int pnum,
- enum bitmap_page_attr attr)
-{
- set_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
-}
-
-static inline void clear_page_attr(struct bitmap *bitmap, int pnum,
- enum bitmap_page_attr attr)
-{
- clear_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
-}
-
-static inline int test_page_attr(struct bitmap *bitmap, int pnum,
- enum bitmap_page_attr attr)
-{
- return test_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
-}
-
-static inline int test_and_clear_page_attr(struct bitmap *bitmap, int pnum,
- enum bitmap_page_attr attr)
-{
- return test_and_clear_bit((pnum<<2) + attr,
- bitmap->storage.filemap_attr);
-}
-/*
- * bitmap_file_set_bit -- called before performing a write to the md device
- * to set (and eventually sync) a particular bit in the bitmap file
- *
- * we set the bit immediately, then we record the page number so that
- * when an unplug occurs, we can flush the dirty pages out to disk
- */
-static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
-{
- unsigned long bit;
- struct page *page;
- void *kaddr;
- unsigned long chunk = block >> bitmap->counts.chunkshift;
- struct bitmap_storage *store = &bitmap->storage;
- unsigned long node_offset = 0;
-
- if (mddev_is_clustered(bitmap->mddev))
- node_offset = bitmap->cluster_slot * store->file_pages;
-
- page = filemap_get_page(&bitmap->storage, chunk);
- if (!page)
- return;
- bit = file_page_offset(&bitmap->storage, chunk);
-
- /* set the bit */
- kaddr = kmap_atomic(page);
- if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
- set_bit(bit, kaddr);
- else
- set_bit_le(bit, kaddr);
- kunmap_atomic(kaddr);
- pr_debug("set file bit %lu page %lu\n", bit, page->index);
- /* record page number so it gets flushed to disk when unplug occurs */
- set_page_attr(bitmap, page->index - node_offset, BITMAP_PAGE_DIRTY);
-}
-
-static void bitmap_file_clear_bit(struct bitmap *bitmap, sector_t block)
-{
- unsigned long bit;
- struct page *page;
- void *paddr;
- unsigned long chunk = block >> bitmap->counts.chunkshift;
- struct bitmap_storage *store = &bitmap->storage;
- unsigned long node_offset = 0;
-
- if (mddev_is_clustered(bitmap->mddev))
- node_offset = bitmap->cluster_slot * store->file_pages;
-
- page = filemap_get_page(&bitmap->storage, chunk);
- if (!page)
- return;
- bit = file_page_offset(&bitmap->storage, chunk);
- paddr = kmap_atomic(page);
- if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
- clear_bit(bit, paddr);
- else
- clear_bit_le(bit, paddr);
- kunmap_atomic(paddr);
- if (!test_page_attr(bitmap, page->index - node_offset, BITMAP_PAGE_NEEDWRITE)) {
- set_page_attr(bitmap, page->index - node_offset, BITMAP_PAGE_PENDING);
- bitmap->allclean = 0;
- }
-}
-
-static int bitmap_file_test_bit(struct bitmap *bitmap, sector_t block)
-{
- unsigned long bit;
- struct page *page;
- void *paddr;
- unsigned long chunk = block >> bitmap->counts.chunkshift;
- int set = 0;
-
- page = filemap_get_page(&bitmap->storage, chunk);
- if (!page)
- return -EINVAL;
- bit = file_page_offset(&bitmap->storage, chunk);
- paddr = kmap_atomic(page);
- if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
- set = test_bit(bit, paddr);
- else
- set = test_bit_le(bit, paddr);
- kunmap_atomic(paddr);
- return set;
-}
-
-
-/* this gets called when the md device is ready to unplug its underlying
- * (slave) device queues -- before we let any writes go down, we need to
- * sync the dirty pages of the bitmap file to disk */
-void bitmap_unplug(struct bitmap *bitmap)
-{
- unsigned long i;
- int dirty, need_write;
- int writing = 0;
-
- if (!bitmap || !bitmap->storage.filemap ||
- test_bit(BITMAP_STALE, &bitmap->flags))
- return;
-
- /* look at each page to see if there are any set bits that need to be
- * flushed out to disk */
- for (i = 0; i < bitmap->storage.file_pages; i++) {
- if (!bitmap->storage.filemap)
- return;
- dirty = test_and_clear_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
- need_write = test_and_clear_page_attr(bitmap, i,
- BITMAP_PAGE_NEEDWRITE);
- if (dirty || need_write) {
- if (!writing) {
- bitmap_wait_writes(bitmap);
- if (bitmap->mddev->queue)
- blk_add_trace_msg(bitmap->mddev->queue,
- "md bitmap_unplug");
- }
- clear_page_attr(bitmap, i, BITMAP_PAGE_PENDING);
- write_page(bitmap, bitmap->storage.filemap[i], 0);
- writing = 1;
- }
- }
- if (writing)
- bitmap_wait_writes(bitmap);
-
- if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
- bitmap_file_kick(bitmap);
-}
-EXPORT_SYMBOL(bitmap_unplug);
-
-static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
-/* * bitmap_init_from_disk -- called at bitmap_create time to initialize
- * the in-memory bitmap from the on-disk bitmap -- also, sets up the
- * memory mapping of the bitmap file
- * Special cases:
- * if there's no bitmap file, or if the bitmap file had been
- * previously kicked from the array, we mark all the bits as
- * 1's in order to cause a full resync.
- *
- * We ignore all bits for sectors that end earlier than 'start'.
- * This is used when reading an out-of-date bitmap...
- */
-static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
-{
- unsigned long i, chunks, index, oldindex, bit, node_offset = 0;
- struct page *page = NULL;
- unsigned long bit_cnt = 0;
- struct file *file;
- unsigned long offset;
- int outofdate;
- int ret = -ENOSPC;
- void *paddr;
- struct bitmap_storage *store = &bitmap->storage;
-
- chunks = bitmap->counts.chunks;
- file = store->file;
-
- if (!file && !bitmap->mddev->bitmap_info.offset) {
- /* No permanent bitmap - fill with '1s'. */
- store->filemap = NULL;
- store->file_pages = 0;
- for (i = 0; i < chunks ; i++) {
- /* if the disk bit is set, set the memory bit */
- int needed = ((sector_t)(i+1) << (bitmap->counts.chunkshift)
- >= start);
- bitmap_set_memory_bits(bitmap,
- (sector_t)i << bitmap->counts.chunkshift,
- needed);
- }
- return 0;
- }
-
- outofdate = test_bit(BITMAP_STALE, &bitmap->flags);
- if (outofdate)
- pr_warn("%s: bitmap file is out of date, doing full recovery\n", bmname(bitmap));
-
- if (file && i_size_read(file->f_mapping->host) < store->bytes) {
- pr_warn("%s: bitmap file too short %lu < %lu\n",
- bmname(bitmap),
- (unsigned long) i_size_read(file->f_mapping->host),
- store->bytes);
- goto err;
- }
-
- oldindex = ~0L;
- offset = 0;
- if (!bitmap->mddev->bitmap_info.external)
- offset = sizeof(bitmap_super_t);
-
- if (mddev_is_clustered(bitmap->mddev))
- node_offset = bitmap->cluster_slot * (DIV_ROUND_UP(store->bytes, PAGE_SIZE));
-
- for (i = 0; i < chunks; i++) {
- int b;
- index = file_page_index(&bitmap->storage, i);
- bit = file_page_offset(&bitmap->storage, i);
- if (index != oldindex) { /* this is a new page, read it in */
- int count;
- /* unmap the old page, we're done with it */
- if (index == store->file_pages-1)
- count = store->bytes - index * PAGE_SIZE;
- else
- count = PAGE_SIZE;
- page = store->filemap[index];
- if (file)
- ret = read_page(file, index, bitmap,
- count, page);
- else
- ret = read_sb_page(
- bitmap->mddev,
- bitmap->mddev->bitmap_info.offset,
- page,
- index + node_offset, count);
-
- if (ret)
- goto err;
-
- oldindex = index;
-
- if (outofdate) {
- /*
- * if bitmap is out of date, dirty the
- * whole page and write it out
- */
- paddr = kmap_atomic(page);
- memset(paddr + offset, 0xff,
- PAGE_SIZE - offset);
- kunmap_atomic(paddr);
- write_page(bitmap, page, 1);
-
- ret = -EIO;
- if (test_bit(BITMAP_WRITE_ERROR,
- &bitmap->flags))
- goto err;
- }
- }
- paddr = kmap_atomic(page);
- if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
- b = test_bit(bit, paddr);
- else
- b = test_bit_le(bit, paddr);
- kunmap_atomic(paddr);
- if (b) {
- /* if the disk bit is set, set the memory bit */
- int needed = ((sector_t)(i+1) << bitmap->counts.chunkshift
- >= start);
- bitmap_set_memory_bits(bitmap,
- (sector_t)i << bitmap->counts.chunkshift,
- needed);
- bit_cnt++;
- }
- offset = 0;
- }
-
- pr_debug("%s: bitmap initialized from disk: read %lu pages, set %lu of %lu bits\n",
- bmname(bitmap), store->file_pages,
- bit_cnt, chunks);
-
- return 0;
-
- err:
- pr_warn("%s: bitmap initialisation failed: %d\n",
- bmname(bitmap), ret);
- return ret;
-}
-
-void bitmap_write_all(struct bitmap *bitmap)
-{
- /* We don't actually write all bitmap blocks here,
- * just flag them as needing to be written
- */
- int i;
-
- if (!bitmap || !bitmap->storage.filemap)
- return;
- if (bitmap->storage.file)
- /* Only one copy, so nothing needed */
- return;
-
- for (i = 0; i < bitmap->storage.file_pages; i++)
- set_page_attr(bitmap, i,
- BITMAP_PAGE_NEEDWRITE);
- bitmap->allclean = 0;
-}
-
-static void bitmap_count_page(struct bitmap_counts *bitmap,
- sector_t offset, int inc)
-{
- sector_t chunk = offset >> bitmap->chunkshift;
- unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
- bitmap->bp[page].count += inc;
- bitmap_checkfree(bitmap, page);
-}
-
-static void bitmap_set_pending(struct bitmap_counts *bitmap, sector_t offset)
-{
- sector_t chunk = offset >> bitmap->chunkshift;
- unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
- struct bitmap_page *bp = &bitmap->bp[page];
-
- if (!bp->pending)
- bp->pending = 1;
-}
-
-static bitmap_counter_t *bitmap_get_counter(struct bitmap_counts *bitmap,
- sector_t offset, sector_t *blocks,
- int create);
-
-/*
- * bitmap daemon -- periodically wakes up to clean bits and flush pages
- * out to disk
- */
-
-void bitmap_daemon_work(struct mddev *mddev)
-{
- struct bitmap *bitmap;
- unsigned long j;
- unsigned long nextpage;
- sector_t blocks;
- struct bitmap_counts *counts;
-
- /* Use a mutex to guard daemon_work against
- * bitmap_destroy.
- */
- mutex_lock(&mddev->bitmap_info.mutex);
- bitmap = mddev->bitmap;
- if (bitmap == NULL) {
- mutex_unlock(&mddev->bitmap_info.mutex);
- return;
- }
- if (time_before(jiffies, bitmap->daemon_lastrun
- + mddev->bitmap_info.daemon_sleep))
- goto done;
-
- bitmap->daemon_lastrun = jiffies;
- if (bitmap->allclean) {
- mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
- goto done;
- }
- bitmap->allclean = 1;
-
- if (bitmap->mddev->queue)
- blk_add_trace_msg(bitmap->mddev->queue,
- "md bitmap_daemon_work");
-
- /* Any file-page which is PENDING now needs to be written.
- * So set NEEDWRITE now, then after we make any last-minute changes
- * we will write it.
- */
- for (j = 0; j < bitmap->storage.file_pages; j++)
- if (test_and_clear_page_attr(bitmap, j,
- BITMAP_PAGE_PENDING))
- set_page_attr(bitmap, j,
- BITMAP_PAGE_NEEDWRITE);
-
- if (bitmap->need_sync &&
- mddev->bitmap_info.external == 0) {
- /* Arrange for superblock update as well as
- * other changes */
- bitmap_super_t *sb;
- bitmap->need_sync = 0;
- if (bitmap->storage.filemap) {
- sb = kmap_atomic(bitmap->storage.sb_page);
- sb->events_cleared =
- cpu_to_le64(bitmap->events_cleared);
- kunmap_atomic(sb);
- set_page_attr(bitmap, 0,
- BITMAP_PAGE_NEEDWRITE);
- }
- }
- /* Now look at the bitmap counters and if any are '2' or '1',
- * decrement and handle accordingly.
- */
- counts = &bitmap->counts;
- spin_lock_irq(&counts->lock);
- nextpage = 0;
- for (j = 0; j < counts->chunks; j++) {
- bitmap_counter_t *bmc;
- sector_t block = (sector_t)j << counts->chunkshift;
-
- if (j == nextpage) {
- nextpage += PAGE_COUNTER_RATIO;
- if (!counts->bp[j >> PAGE_COUNTER_SHIFT].pending) {
- j |= PAGE_COUNTER_MASK;
- continue;
- }
- counts->bp[j >> PAGE_COUNTER_SHIFT].pending = 0;
- }
- bmc = bitmap_get_counter(counts,
- block,
- &blocks, 0);
-
- if (!bmc) {
- j |= PAGE_COUNTER_MASK;
- continue;
- }
- if (*bmc == 1 && !bitmap->need_sync) {
- /* We can clear the bit */
- *bmc = 0;
- bitmap_count_page(counts, block, -1);
- bitmap_file_clear_bit(bitmap, block);
- } else if (*bmc && *bmc <= 2) {
- *bmc = 1;
- bitmap_set_pending(counts, block);
- bitmap->allclean = 0;
- }
- }
- spin_unlock_irq(&counts->lock);
-
- bitmap_wait_writes(bitmap);
- /* Now start writeout on any page in NEEDWRITE that isn't DIRTY.
- * DIRTY pages need to be written by bitmap_unplug so it can wait
- * for them.
- * If we find any DIRTY page we stop there and let bitmap_unplug
- * handle all the rest. This is important in the case where
- * the first blocking holds the superblock and it has been updated.
- * We mustn't write any other blocks before the superblock.
- */
- for (j = 0;
- j < bitmap->storage.file_pages
- && !test_bit(BITMAP_STALE, &bitmap->flags);
- j++) {
- if (test_page_attr(bitmap, j,
- BITMAP_PAGE_DIRTY))
- /* bitmap_unplug will handle the rest */
- break;
- if (test_and_clear_page_attr(bitmap, j,
- BITMAP_PAGE_NEEDWRITE)) {
- write_page(bitmap, bitmap->storage.filemap[j], 0);
- }
- }
-
- done:
- if (bitmap->allclean == 0)
- mddev->thread->timeout =
- mddev->bitmap_info.daemon_sleep;
- mutex_unlock(&mddev->bitmap_info.mutex);
-}
-
-static bitmap_counter_t *bitmap_get_counter(struct bitmap_counts *bitmap,
- sector_t offset, sector_t *blocks,
- int create)
-__releases(bitmap->lock)
-__acquires(bitmap->lock)
-{
- /* If 'create', we might release the lock and reclaim it.
- * The lock must have been taken with interrupts enabled.
- * If !create, we don't release the lock.
- */
- sector_t chunk = offset >> bitmap->chunkshift;
- unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
- unsigned long pageoff = (chunk & PAGE_COUNTER_MASK) << COUNTER_BYTE_SHIFT;
- sector_t csize;
- int err;
-
- err = bitmap_checkpage(bitmap, page, create, 0);
-
- if (bitmap->bp[page].hijacked ||
- bitmap->bp[page].map == NULL)
- csize = ((sector_t)1) << (bitmap->chunkshift +
- PAGE_COUNTER_SHIFT - 1);
- else
- csize = ((sector_t)1) << bitmap->chunkshift;
- *blocks = csize - (offset & (csize - 1));
-
- if (err < 0)
- return NULL;
-
- /* now locked ... */
-
- if (bitmap->bp[page].hijacked) { /* hijacked pointer */
- /* should we use the first or second counter field
- * of the hijacked pointer? */
- int hi = (pageoff > PAGE_COUNTER_MASK);
- return &((bitmap_counter_t *)
- &bitmap->bp[page].map)[hi];
- } else /* page is allocated */
- return (bitmap_counter_t *)
- &(bitmap->bp[page].map[pageoff]);
-}
-
-int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind)
-{
- if (!bitmap)
- return 0;
-
- if (behind) {
- int bw;
- atomic_inc(&bitmap->behind_writes);
- bw = atomic_read(&bitmap->behind_writes);
- if (bw > bitmap->behind_writes_used)
- bitmap->behind_writes_used = bw;
-
- pr_debug("inc write-behind count %d/%lu\n",
- bw, bitmap->mddev->bitmap_info.max_write_behind);
- }
-
- while (sectors) {
- sector_t blocks;
- bitmap_counter_t *bmc;
-
- spin_lock_irq(&bitmap->counts.lock);
- bmc = bitmap_get_counter(&bitmap->counts, offset, &blocks, 1);
- if (!bmc) {
- spin_unlock_irq(&bitmap->counts.lock);
- return 0;
- }
-
- if (unlikely(COUNTER(*bmc) == COUNTER_MAX)) {
- DEFINE_WAIT(__wait);
- /* note that it is safe to do the prepare_to_wait
- * after the test as long as we do it before dropping
- * the spinlock.
- */
- prepare_to_wait(&bitmap->overflow_wait, &__wait,
- TASK_UNINTERRUPTIBLE);
- spin_unlock_irq(&bitmap->counts.lock);
- schedule();
- finish_wait(&bitmap->overflow_wait, &__wait);
- continue;
- }
-
- switch (*bmc) {
- case 0:
- bitmap_file_set_bit(bitmap, offset);
- bitmap_count_page(&bitmap->counts, offset, 1);
- /* fall through */
- case 1:
- *bmc = 2;
- }
-
- (*bmc)++;
-
- spin_unlock_irq(&bitmap->counts.lock);
-
- offset += blocks;
- if (sectors > blocks)
- sectors -= blocks;
- else
- sectors = 0;
- }
- return 0;
-}
-EXPORT_SYMBOL(bitmap_startwrite);
-
-void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
- int success, int behind)
-{
- if (!bitmap)
- return;
- if (behind) {
- if (atomic_dec_and_test(&bitmap->behind_writes))
- wake_up(&bitmap->behind_wait);
- pr_debug("dec write-behind count %d/%lu\n",
- atomic_read(&bitmap->behind_writes),
- bitmap->mddev->bitmap_info.max_write_behind);
- }
-
- while (sectors) {
- sector_t blocks;
- unsigned long flags;
- bitmap_counter_t *bmc;
-
- spin_lock_irqsave(&bitmap->counts.lock, flags);
- bmc = bitmap_get_counter(&bitmap->counts, offset, &blocks, 0);
- if (!bmc) {
- spin_unlock_irqrestore(&bitmap->counts.lock, flags);
- return;
- }
-
- if (success && !bitmap->mddev->degraded &&
- bitmap->events_cleared < bitmap->mddev->events) {
- bitmap->events_cleared = bitmap->mddev->events;
- bitmap->need_sync = 1;
- sysfs_notify_dirent_safe(bitmap->sysfs_can_clear);
- }
-
- if (!success && !NEEDED(*bmc))
- *bmc |= NEEDED_MASK;
-
- if (COUNTER(*bmc) == COUNTER_MAX)
- wake_up(&bitmap->overflow_wait);
-
- (*bmc)--;
- if (*bmc <= 2) {
- bitmap_set_pending(&bitmap->counts, offset);
- bitmap->allclean = 0;
- }
- spin_unlock_irqrestore(&bitmap->counts.lock, flags);
- offset += blocks;
- if (sectors > blocks)
- sectors -= blocks;
- else
- sectors = 0;
- }
-}
-EXPORT_SYMBOL(bitmap_endwrite);
-
-static int __bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks,
- int degraded)
-{
- bitmap_counter_t *bmc;
- int rv;
- if (bitmap == NULL) {/* FIXME or bitmap set as 'failed' */
- *blocks = 1024;
- return 1; /* always resync if no bitmap */
- }
- spin_lock_irq(&bitmap->counts.lock);
- bmc = bitmap_get_counter(&bitmap->counts, offset, blocks, 0);
- rv = 0;
- if (bmc) {
- /* locked */
- if (RESYNC(*bmc))
- rv = 1;
- else if (NEEDED(*bmc)) {
- rv = 1;
- if (!degraded) { /* don't set/clear bits if degraded */
- *bmc |= RESYNC_MASK;
- *bmc &= ~NEEDED_MASK;
- }
- }
- }
- spin_unlock_irq(&bitmap->counts.lock);
- return rv;
-}
-
-int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks,
- int degraded)
-{
- /* bitmap_start_sync must always report on multiples of whole
- * pages, otherwise resync (which is very PAGE_SIZE based) will
- * get confused.
- * So call __bitmap_start_sync repeatedly (if needed) until
- * At least PAGE_SIZE>>9 blocks are covered.
- * Return the 'or' of the result.
- */
- int rv = 0;
- sector_t blocks1;
-
- *blocks = 0;
- while (*blocks < (PAGE_SIZE>>9)) {
- rv |= __bitmap_start_sync(bitmap, offset,
- &blocks1, degraded);
- offset += blocks1;
- *blocks += blocks1;
- }
- return rv;
-}
-EXPORT_SYMBOL(bitmap_start_sync);
-
-void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted)
-{
- bitmap_counter_t *bmc;
- unsigned long flags;
-
- if (bitmap == NULL) {
- *blocks = 1024;
- return;
- }
- spin_lock_irqsave(&bitmap->counts.lock, flags);
- bmc = bitmap_get_counter(&bitmap->counts, offset, blocks, 0);
- if (bmc == NULL)
- goto unlock;
- /* locked */
- if (RESYNC(*bmc)) {
- *bmc &= ~RESYNC_MASK;
-
- if (!NEEDED(*bmc) && aborted)
- *bmc |= NEEDED_MASK;
- else {
- if (*bmc <= 2) {
- bitmap_set_pending(&bitmap->counts, offset);
- bitmap->allclean = 0;
- }
- }
- }
- unlock:
- spin_unlock_irqrestore(&bitmap->counts.lock, flags);
-}
-EXPORT_SYMBOL(bitmap_end_sync);
-
-void bitmap_close_sync(struct bitmap *bitmap)
-{
- /* Sync has finished, and any bitmap chunks that weren't synced
- * properly have been aborted. It remains to us to clear the
- * RESYNC bit wherever it is still on
- */
- sector_t sector = 0;
- sector_t blocks;
- if (!bitmap)
- return;
- while (sector < bitmap->mddev->resync_max_sectors) {
- bitmap_end_sync(bitmap, sector, &blocks, 0);
- sector += blocks;
- }
-}
-EXPORT_SYMBOL(bitmap_close_sync);
-
-void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector, bool force)
-{
- sector_t s = 0;
- sector_t blocks;
-
- if (!bitmap)
- return;
- if (sector == 0) {
- bitmap->last_end_sync = jiffies;
- return;
- }
- if (!force && time_before(jiffies, (bitmap->last_end_sync
- + bitmap->mddev->bitmap_info.daemon_sleep)))
- return;
- wait_event(bitmap->mddev->recovery_wait,
- atomic_read(&bitmap->mddev->recovery_active) == 0);
-
- bitmap->mddev->curr_resync_completed = sector;
- set_bit(MD_SB_CHANGE_CLEAN, &bitmap->mddev->sb_flags);
- sector &= ~((1ULL << bitmap->counts.chunkshift) - 1);
- s = 0;
- while (s < sector && s < bitmap->mddev->resync_max_sectors) {
- bitmap_end_sync(bitmap, s, &blocks, 0);
- s += blocks;
- }
- bitmap->last_end_sync = jiffies;
- sysfs_notify(&bitmap->mddev->kobj, NULL, "sync_completed");
-}
-EXPORT_SYMBOL(bitmap_cond_end_sync);
-
-void bitmap_sync_with_cluster(struct mddev *mddev,
- sector_t old_lo, sector_t old_hi,
- sector_t new_lo, sector_t new_hi)
-{
- struct bitmap *bitmap = mddev->bitmap;
- sector_t sector, blocks = 0;
-
- for (sector = old_lo; sector < new_lo; ) {
- bitmap_end_sync(bitmap, sector, &blocks, 0);
- sector += blocks;
- }
- WARN((blocks > new_lo) && old_lo, "alignment is not correct for lo\n");
-
- for (sector = old_hi; sector < new_hi; ) {
- bitmap_start_sync(bitmap, sector, &blocks, 0);
- sector += blocks;
- }
- WARN((blocks > new_hi) && old_hi, "alignment is not correct for hi\n");
-}
-EXPORT_SYMBOL(bitmap_sync_with_cluster);
-
-static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed)
-{
- /* For each chunk covered by any of these sectors, set the
- * counter to 2 and possibly set resync_needed. They should all
- * be 0 at this point
- */
-
- sector_t secs;
- bitmap_counter_t *bmc;
- spin_lock_irq(&bitmap->counts.lock);
- bmc = bitmap_get_counter(&bitmap->counts, offset, &secs, 1);
- if (!bmc) {
- spin_unlock_irq(&bitmap->counts.lock);
- return;
- }
- if (!*bmc) {
- *bmc = 2;
- bitmap_count_page(&bitmap->counts, offset, 1);
- bitmap_set_pending(&bitmap->counts, offset);
- bitmap->allclean = 0;
- }
- if (needed)
- *bmc |= NEEDED_MASK;
- spin_unlock_irq(&bitmap->counts.lock);
-}
-
-/* dirty the memory and file bits for bitmap chunks "s" to "e" */
-void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e)
-{
- unsigned long chunk;
-
- for (chunk = s; chunk <= e; chunk++) {
- sector_t sec = (sector_t)chunk << bitmap->counts.chunkshift;
- bitmap_set_memory_bits(bitmap, sec, 1);
- bitmap_file_set_bit(bitmap, sec);
- if (sec < bitmap->mddev->recovery_cp)
- /* We are asserting that the array is dirty,
- * so move the recovery_cp address back so
- * that it is obvious that it is dirty
- */
- bitmap->mddev->recovery_cp = sec;
- }
-}
-
-/*
- * flush out any pending updates
- */
-void bitmap_flush(struct mddev *mddev)
-{
- struct bitmap *bitmap = mddev->bitmap;
- long sleep;
-
- if (!bitmap) /* there was no bitmap */
- return;
-
- /* run the daemon_work three time to ensure everything is flushed
- * that can be
- */
- sleep = mddev->bitmap_info.daemon_sleep * 2;
- bitmap->daemon_lastrun -= sleep;
- bitmap_daemon_work(mddev);
- bitmap->daemon_lastrun -= sleep;
- bitmap_daemon_work(mddev);
- bitmap->daemon_lastrun -= sleep;
- bitmap_daemon_work(mddev);
- bitmap_update_sb(bitmap);
-}
-
-/*
- * free memory that was allocated
- */
-void bitmap_free(struct bitmap *bitmap)
-{
- unsigned long k, pages;
- struct bitmap_page *bp;
-
- if (!bitmap) /* there was no bitmap */
- return;
-
- if (bitmap->sysfs_can_clear)
- sysfs_put(bitmap->sysfs_can_clear);
-
- if (mddev_is_clustered(bitmap->mddev) && bitmap->mddev->cluster_info &&
- bitmap->cluster_slot == md_cluster_ops->slot_number(bitmap->mddev))
- md_cluster_stop(bitmap->mddev);
-
- /* Shouldn't be needed - but just in case.... */
- wait_event(bitmap->write_wait,
- atomic_read(&bitmap->pending_writes) == 0);
-
- /* release the bitmap file */
- bitmap_file_unmap(&bitmap->storage);
-
- bp = bitmap->counts.bp;
- pages = bitmap->counts.pages;
-
- /* free all allocated memory */
-
- if (bp) /* deallocate the page memory */
- for (k = 0; k < pages; k++)
- if (bp[k].map && !bp[k].hijacked)
- kfree(bp[k].map);
- kfree(bp);
- kfree(bitmap);
-}
-EXPORT_SYMBOL(bitmap_free);
-
-void bitmap_wait_behind_writes(struct mddev *mddev)
-{
- struct bitmap *bitmap = mddev->bitmap;
-
- /* wait for behind writes to complete */
- if (bitmap && atomic_read(&bitmap->behind_writes) > 0) {
- pr_debug("md:%s: behind writes in progress - waiting to stop.\n",
- mdname(mddev));
- /* need to kick something here to make sure I/O goes? */
- wait_event(bitmap->behind_wait,
- atomic_read(&bitmap->behind_writes) == 0);
- }
-}
-
-void bitmap_destroy(struct mddev *mddev)
-{
- struct bitmap *bitmap = mddev->bitmap;
-
- if (!bitmap) /* there was no bitmap */
- return;
-
- bitmap_wait_behind_writes(mddev);
-
- mutex_lock(&mddev->bitmap_info.mutex);
- spin_lock(&mddev->lock);
- mddev->bitmap = NULL; /* disconnect from the md device */
- spin_unlock(&mddev->lock);
- mutex_unlock(&mddev->bitmap_info.mutex);
- if (mddev->thread)
- mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
-
- bitmap_free(bitmap);
-}
-
-/*
- * initialize the bitmap structure
- * if this returns an error, bitmap_destroy must be called to do clean up
- * once mddev->bitmap is set
- */
-struct bitmap *bitmap_create(struct mddev *mddev, int slot)
-{
- struct bitmap *bitmap;
- sector_t blocks = mddev->resync_max_sectors;
- struct file *file = mddev->bitmap_info.file;
- int err;
- struct kernfs_node *bm = NULL;
-
- BUILD_BUG_ON(sizeof(bitmap_super_t) != 256);
-
- BUG_ON(file && mddev->bitmap_info.offset);
-
- bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL);
- if (!bitmap)
- return ERR_PTR(-ENOMEM);
-
- spin_lock_init(&bitmap->counts.lock);
- atomic_set(&bitmap->pending_writes, 0);
- init_waitqueue_head(&bitmap->write_wait);
- init_waitqueue_head(&bitmap->overflow_wait);
- init_waitqueue_head(&bitmap->behind_wait);
-
- bitmap->mddev = mddev;
- bitmap->cluster_slot = slot;
-
- if (mddev->kobj.sd)
- bm = sysfs_get_dirent(mddev->kobj.sd, "bitmap");
- if (bm) {
- bitmap->sysfs_can_clear = sysfs_get_dirent(bm, "can_clear");
- sysfs_put(bm);
- } else
- bitmap->sysfs_can_clear = NULL;
-
- bitmap->storage.file = file;
- if (file) {
- get_file(file);
- /* As future accesses to this file will use bmap,
- * and bypass the page cache, we must sync the file
- * first.
- */
- vfs_fsync(file, 1);
- }
- /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
- if (!mddev->bitmap_info.external) {
- /*
- * If 'MD_ARRAY_FIRST_USE' is set, then device-mapper is
- * instructing us to create a new on-disk bitmap instance.
- */
- if (test_and_clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags))
- err = bitmap_new_disk_sb(bitmap);
- else
- err = bitmap_read_sb(bitmap);
- } else {
- err = 0;
- if (mddev->bitmap_info.chunksize == 0 ||
- mddev->bitmap_info.daemon_sleep == 0)
- /* chunksize and time_base need to be
- * set first. */
- err = -EINVAL;
- }
- if (err)
- goto error;
-
- bitmap->daemon_lastrun = jiffies;
- err = bitmap_resize(bitmap, blocks, mddev->bitmap_info.chunksize, 1);
- if (err)
- goto error;
-
- pr_debug("created bitmap (%lu pages) for device %s\n",
- bitmap->counts.pages, bmname(bitmap));
-
- err = test_bit(BITMAP_WRITE_ERROR, &bitmap->flags) ? -EIO : 0;
- if (err)
- goto error;
-
- return bitmap;
- error:
- bitmap_free(bitmap);
- return ERR_PTR(err);
-}
-
-int bitmap_load(struct mddev *mddev)
-{
- int err = 0;
- sector_t start = 0;
- sector_t sector = 0;
- struct bitmap *bitmap = mddev->bitmap;
-
- if (!bitmap)
- goto out;
-
- if (mddev_is_clustered(mddev))
- md_cluster_ops->load_bitmaps(mddev, mddev->bitmap_info.nodes);
-
- /* Clear out old bitmap info first: Either there is none, or we
- * are resuming after someone else has possibly changed things,
- * so we should forget old cached info.
- * All chunks should be clean, but some might need_sync.
- */
- while (sector < mddev->resync_max_sectors) {
- sector_t blocks;
- bitmap_start_sync(bitmap, sector, &blocks, 0);
- sector += blocks;
- }
- bitmap_close_sync(bitmap);
-
- if (mddev->degraded == 0
- || bitmap->events_cleared == mddev->events)
- /* no need to keep dirty bits to optimise a
- * re-add of a missing device */
- start = mddev->recovery_cp;
-
- mutex_lock(&mddev->bitmap_info.mutex);
- err = bitmap_init_from_disk(bitmap, start);
- mutex_unlock(&mddev->bitmap_info.mutex);
-
- if (err)
- goto out;
- clear_bit(BITMAP_STALE, &bitmap->flags);
-
- /* Kick recovery in case any bits were set */
- set_bit(MD_RECOVERY_NEEDED, &bitmap->mddev->recovery);
-
- mddev->thread->timeout = mddev->bitmap_info.daemon_sleep;
- md_wakeup_thread(mddev->thread);
-
- bitmap_update_sb(bitmap);
-
- if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
- err = -EIO;
-out:
- return err;
-}
-EXPORT_SYMBOL_GPL(bitmap_load);
-
-struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot)
-{
- int rv = 0;
- struct bitmap *bitmap;
-
- bitmap = bitmap_create(mddev, slot);
- if (IS_ERR(bitmap)) {
- rv = PTR_ERR(bitmap);
- return ERR_PTR(rv);
- }
-
- rv = bitmap_init_from_disk(bitmap, 0);
- if (rv) {
- bitmap_free(bitmap);
- return ERR_PTR(rv);
- }
-
- return bitmap;
-}
-EXPORT_SYMBOL(get_bitmap_from_slot);
-
-/* Loads the bitmap associated with slot and copies the resync information
- * to our bitmap
- */
-int bitmap_copy_from_slot(struct mddev *mddev, int slot,
- sector_t *low, sector_t *high, bool clear_bits)
-{
- int rv = 0, i, j;
- sector_t block, lo = 0, hi = 0;
- struct bitmap_counts *counts;
- struct bitmap *bitmap;
-
- bitmap = get_bitmap_from_slot(mddev, slot);
- if (IS_ERR(bitmap)) {
- pr_err("%s can't get bitmap from slot %d\n", __func__, slot);
- return -1;
- }
-
- counts = &bitmap->counts;
- for (j = 0; j < counts->chunks; j++) {
- block = (sector_t)j << counts->chunkshift;
- if (bitmap_file_test_bit(bitmap, block)) {
- if (!lo)
- lo = block;
- hi = block;
- bitmap_file_clear_bit(bitmap, block);
- bitmap_set_memory_bits(mddev->bitmap, block, 1);
- bitmap_file_set_bit(mddev->bitmap, block);
- }
- }
-
- if (clear_bits) {
- bitmap_update_sb(bitmap);
- /* BITMAP_PAGE_PENDING is set, but bitmap_unplug needs
- * BITMAP_PAGE_DIRTY or _NEEDWRITE to write ... */
- for (i = 0; i < bitmap->storage.file_pages; i++)
- if (test_page_attr(bitmap, i, BITMAP_PAGE_PENDING))
- set_page_attr(bitmap, i, BITMAP_PAGE_NEEDWRITE);
- bitmap_unplug(bitmap);
- }
- bitmap_unplug(mddev->bitmap);
- *low = lo;
- *high = hi;
-
- return rv;
-}
-EXPORT_SYMBOL_GPL(bitmap_copy_from_slot);
-
-
-void bitmap_status(struct seq_file *seq, struct bitmap *bitmap)
-{
- unsigned long chunk_kb;
- struct bitmap_counts *counts;
-
- if (!bitmap)
- return;
-
- counts = &bitmap->counts;
-
- chunk_kb = bitmap->mddev->bitmap_info.chunksize >> 10;
- seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
- "%lu%s chunk",
- counts->pages - counts->missing_pages,
- counts->pages,
- (counts->pages - counts->missing_pages)
- << (PAGE_SHIFT - 10),
- chunk_kb ? chunk_kb : bitmap->mddev->bitmap_info.chunksize,
- chunk_kb ? "KB" : "B");
- if (bitmap->storage.file) {
- seq_printf(seq, ", file: ");
- seq_file_path(seq, bitmap->storage.file, " \t\n");
- }
-
- seq_printf(seq, "\n");
-}
-
-int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
- int chunksize, int init)
-{
- /* If chunk_size is 0, choose an appropriate chunk size.
- * Then possibly allocate new storage space.
- * Then quiesce, copy bits, replace bitmap, and re-start
- *
- * This function is called both to set up the initial bitmap
- * and to resize the bitmap while the array is active.
- * If this happens as a result of the array being resized,
- * chunksize will be zero, and we need to choose a suitable
- * chunksize, otherwise we use what we are given.
- */
- struct bitmap_storage store;
- struct bitmap_counts old_counts;
- unsigned long chunks;
- sector_t block;
- sector_t old_blocks, new_blocks;
- int chunkshift;
- int ret = 0;
- long pages;
- struct bitmap_page *new_bp;
-
- if (bitmap->storage.file && !init) {
- pr_info("md: cannot resize file-based bitmap\n");
- return -EINVAL;
- }
-
- if (chunksize == 0) {
- /* If there is enough space, leave the chunk size unchanged,
- * else increase by factor of two until there is enough space.
- */
- long bytes;
- long space = bitmap->mddev->bitmap_info.space;
-
- if (space == 0) {
- /* We don't know how much space there is, so limit
- * to current size - in sectors.
- */
- bytes = DIV_ROUND_UP(bitmap->counts.chunks, 8);
- if (!bitmap->mddev->bitmap_info.external)
- bytes += sizeof(bitmap_super_t);
- space = DIV_ROUND_UP(bytes, 512);
- bitmap->mddev->bitmap_info.space = space;
- }
- chunkshift = bitmap->counts.chunkshift;
- chunkshift--;
- do {
- /* 'chunkshift' is shift from block size to chunk size */
- chunkshift++;
- chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << chunkshift);
- bytes = DIV_ROUND_UP(chunks, 8);
- if (!bitmap->mddev->bitmap_info.external)
- bytes += sizeof(bitmap_super_t);
- } while (bytes > (space << 9));
- } else
- chunkshift = ffz(~chunksize) - BITMAP_BLOCK_SHIFT;
-
- chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << chunkshift);
- memset(&store, 0, sizeof(store));
- if (bitmap->mddev->bitmap_info.offset || bitmap->mddev->bitmap_info.file)
- ret = bitmap_storage_alloc(&store, chunks,
- !bitmap->mddev->bitmap_info.external,
- mddev_is_clustered(bitmap->mddev)
- ? bitmap->cluster_slot : 0);
- if (ret) {
- bitmap_file_unmap(&store);
- goto err;
- }
-
- pages = DIV_ROUND_UP(chunks, PAGE_COUNTER_RATIO);
-
- new_bp = kzalloc(pages * sizeof(*new_bp), GFP_KERNEL);
- ret = -ENOMEM;
- if (!new_bp) {
- bitmap_file_unmap(&store);
- goto err;
- }
-
- if (!init)
- bitmap->mddev->pers->quiesce(bitmap->mddev, 1);
-
- store.file = bitmap->storage.file;
- bitmap->storage.file = NULL;
-
- if (store.sb_page && bitmap->storage.sb_page)
- memcpy(page_address(store.sb_page),
- page_address(bitmap->storage.sb_page),
- sizeof(bitmap_super_t));
- bitmap_file_unmap(&bitmap->storage);
- bitmap->storage = store;
-
- old_counts = bitmap->counts;
- bitmap->counts.bp = new_bp;
- bitmap->counts.pages = pages;
- bitmap->counts.missing_pages = pages;
- bitmap->counts.chunkshift = chunkshift;
- bitmap->counts.chunks = chunks;
- bitmap->mddev->bitmap_info.chunksize = 1 << (chunkshift +
- BITMAP_BLOCK_SHIFT);
-
- blocks = min(old_counts.chunks << old_counts.chunkshift,
- chunks << chunkshift);
-
- spin_lock_irq(&bitmap->counts.lock);
- /* For cluster raid, need to pre-allocate bitmap */
- if (mddev_is_clustered(bitmap->mddev)) {
- unsigned long page;
- for (page = 0; page < pages; page++) {
- ret = bitmap_checkpage(&bitmap->counts, page, 1, 1);
- if (ret) {
- unsigned long k;
-
- /* deallocate the page memory */
- for (k = 0; k < page; k++) {
- kfree(new_bp[k].map);
- }
-
- /* restore some fields from old_counts */
- bitmap->counts.bp = old_counts.bp;
- bitmap->counts.pages = old_counts.pages;
- bitmap->counts.missing_pages = old_counts.pages;
- bitmap->counts.chunkshift = old_counts.chunkshift;
- bitmap->counts.chunks = old_counts.chunks;
- bitmap->mddev->bitmap_info.chunksize = 1 << (old_counts.chunkshift +
- BITMAP_BLOCK_SHIFT);
- blocks = old_counts.chunks << old_counts.chunkshift;
- pr_warn("Could not pre-allocate in-memory bitmap for cluster raid\n");
- break;
- } else
- bitmap->counts.bp[page].count += 1;
- }
- }
-
- for (block = 0; block < blocks; ) {
- bitmap_counter_t *bmc_old, *bmc_new;
- int set;
-
- bmc_old = bitmap_get_counter(&old_counts, block,
- &old_blocks, 0);
- set = bmc_old && NEEDED(*bmc_old);
-
- if (set) {
- bmc_new = bitmap_get_counter(&bitmap->counts, block,
- &new_blocks, 1);
- if (*bmc_new == 0) {
- /* need to set on-disk bits too. */
- sector_t end = block + new_blocks;
- sector_t start = block >> chunkshift;
- start <<= chunkshift;
- while (start < end) {
- bitmap_file_set_bit(bitmap, block);
- start += 1 << chunkshift;
- }
- *bmc_new = 2;
- bitmap_count_page(&bitmap->counts,
- block, 1);
- bitmap_set_pending(&bitmap->counts,
- block);
- }
- *bmc_new |= NEEDED_MASK;
- if (new_blocks < old_blocks)
- old_blocks = new_blocks;
- }
- block += old_blocks;
- }
-
- if (!init) {
- int i;
- while (block < (chunks << chunkshift)) {
- bitmap_counter_t *bmc;
- bmc = bitmap_get_counter(&bitmap->counts, block,
- &new_blocks, 1);
- if (bmc) {
- /* new space. It needs to be resynced, so
- * we set NEEDED_MASK.
- */
- if (*bmc == 0) {
- *bmc = NEEDED_MASK | 2;
- bitmap_count_page(&bitmap->counts,
- block, 1);
- bitmap_set_pending(&bitmap->counts,
- block);
- }
- }
- block += new_blocks;
- }
- for (i = 0; i < bitmap->storage.file_pages; i++)
- set_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
- }
- spin_unlock_irq(&bitmap->counts.lock);
-
- if (!init) {
- bitmap_unplug(bitmap);
- bitmap->mddev->pers->quiesce(bitmap->mddev, 0);
- }
- ret = 0;
-err:
- return ret;
-}
-EXPORT_SYMBOL_GPL(bitmap_resize);
-
-static ssize_t
-location_show(struct mddev *mddev, char *page)
-{
- ssize_t len;
- if (mddev->bitmap_info.file)
- len = sprintf(page, "file");
- else if (mddev->bitmap_info.offset)
- len = sprintf(page, "%+lld", (long long)mddev->bitmap_info.offset);
- else
- len = sprintf(page, "none");
- len += sprintf(page+len, "\n");
- return len;
-}
-
-static ssize_t
-location_store(struct mddev *mddev, const char *buf, size_t len)
-{
- int rv;
-
- rv = mddev_lock(mddev);
- if (rv)
- return rv;
- if (mddev->pers) {
- if (!mddev->pers->quiesce) {
- rv = -EBUSY;
- goto out;
- }
- if (mddev->recovery || mddev->sync_thread) {
- rv = -EBUSY;
- goto out;
- }
- }
-
- if (mddev->bitmap || mddev->bitmap_info.file ||
- mddev->bitmap_info.offset) {
- /* bitmap already configured. Only option is to clear it */
- if (strncmp(buf, "none", 4) != 0) {
- rv = -EBUSY;
- goto out;
- }
- if (mddev->pers) {
- mddev->pers->quiesce(mddev, 1);
- bitmap_destroy(mddev);
- mddev->pers->quiesce(mddev, 0);
- }
- mddev->bitmap_info.offset = 0;
- if (mddev->bitmap_info.file) {
- struct file *f = mddev->bitmap_info.file;
- mddev->bitmap_info.file = NULL;
- fput(f);
- }
- } else {
- /* No bitmap, OK to set a location */
- long long offset;
- if (strncmp(buf, "none", 4) == 0)
- /* nothing to be done */;
- else if (strncmp(buf, "file:", 5) == 0) {
- /* Not supported yet */
- rv = -EINVAL;
- goto out;
- } else {
- if (buf[0] == '+')
- rv = kstrtoll(buf+1, 10, &offset);
- else
- rv = kstrtoll(buf, 10, &offset);
- if (rv)
- goto out;
- if (offset == 0) {
- rv = -EINVAL;
- goto out;
- }
- if (mddev->bitmap_info.external == 0 &&
- mddev->major_version == 0 &&
- offset != mddev->bitmap_info.default_offset) {
- rv = -EINVAL;
- goto out;
- }
- mddev->bitmap_info.offset = offset;
- if (mddev->pers) {
- struct bitmap *bitmap;
- mddev->pers->quiesce(mddev, 1);
- bitmap = bitmap_create(mddev, -1);
- if (IS_ERR(bitmap))
- rv = PTR_ERR(bitmap);
- else {
- mddev->bitmap = bitmap;
- rv = bitmap_load(mddev);
- if (rv)
- mddev->bitmap_info.offset = 0;
- }
- mddev->pers->quiesce(mddev, 0);
- if (rv) {
- bitmap_destroy(mddev);
- goto out;
- }
- }
- }
- }
- if (!mddev->external) {
- /* Ensure new bitmap info is stored in
- * metadata promptly.
- */
- set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
- md_wakeup_thread(mddev->thread);
- }
- rv = 0;
-out:
- mddev_unlock(mddev);
- if (rv)
- return rv;
- return len;
-}
-
-static struct md_sysfs_entry bitmap_location =
-__ATTR(location, S_IRUGO|S_IWUSR, location_show, location_store);
-
-/* 'bitmap/space' is the space available at 'location' for the
- * bitmap. This allows the kernel to know when it is safe to
- * resize the bitmap to match a resized array.
- */
-static ssize_t
-space_show(struct mddev *mddev, char *page)
-{
- return sprintf(page, "%lu\n", mddev->bitmap_info.space);
-}
-
-static ssize_t
-space_store(struct mddev *mddev, const char *buf, size_t len)
-{
- unsigned long sectors;
- int rv;
-
- rv = kstrtoul(buf, 10, §ors);
- if (rv)
- return rv;
-
- if (sectors == 0)
- return -EINVAL;
-
- if (mddev->bitmap &&
- sectors < (mddev->bitmap->storage.bytes + 511) >> 9)
- return -EFBIG; /* Bitmap is too big for this small space */
-
- /* could make sure it isn't too big, but that isn't really
- * needed - user-space should be careful.
- */
- mddev->bitmap_info.space = sectors;
- return len;
-}
-
-static struct md_sysfs_entry bitmap_space =
-__ATTR(space, S_IRUGO|S_IWUSR, space_show, space_store);
-
-static ssize_t
-timeout_show(struct mddev *mddev, char *page)
-{
- ssize_t len;
- unsigned long secs = mddev->bitmap_info.daemon_sleep / HZ;
- unsigned long jifs = mddev->bitmap_info.daemon_sleep % HZ;
-
- len = sprintf(page, "%lu", secs);
- if (jifs)
- len += sprintf(page+len, ".%03u", jiffies_to_msecs(jifs));
- len += sprintf(page+len, "\n");
- return len;
-}
-
-static ssize_t
-timeout_store(struct mddev *mddev, const char *buf, size_t len)
-{
- /* timeout can be set at any time */
- unsigned long timeout;
- int rv = strict_strtoul_scaled(buf, &timeout, 4);
- if (rv)
- return rv;
-
- /* just to make sure we don't overflow... */
- if (timeout >= LONG_MAX / HZ)
- return -EINVAL;
-
- timeout = timeout * HZ / 10000;
-
- if (timeout >= MAX_SCHEDULE_TIMEOUT)
- timeout = MAX_SCHEDULE_TIMEOUT-1;
- if (timeout < 1)
- timeout = 1;
- mddev->bitmap_info.daemon_sleep = timeout;
- if (mddev->thread) {
- /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
- * the bitmap is all clean and we don't need to
- * adjust the timeout right now
- */
- if (mddev->thread->timeout < MAX_SCHEDULE_TIMEOUT) {
- mddev->thread->timeout = timeout;
- md_wakeup_thread(mddev->thread);
- }
- }
- return len;
-}
-
-static struct md_sysfs_entry bitmap_timeout =
-__ATTR(time_base, S_IRUGO|S_IWUSR, timeout_show, timeout_store);
-
-static ssize_t
-backlog_show(struct mddev *mddev, char *page)
-{
- return sprintf(page, "%lu\n", mddev->bitmap_info.max_write_behind);
-}
-
-static ssize_t
-backlog_store(struct mddev *mddev, const char *buf, size_t len)
-{
- unsigned long backlog;
- int rv = kstrtoul(buf, 10, &backlog);
- if (rv)
- return rv;
- if (backlog > COUNTER_MAX)
- return -EINVAL;
- mddev->bitmap_info.max_write_behind = backlog;
- return len;
-}
-
-static struct md_sysfs_entry bitmap_backlog =
-__ATTR(backlog, S_IRUGO|S_IWUSR, backlog_show, backlog_store);
-
-static ssize_t
-chunksize_show(struct mddev *mddev, char *page)
-{
- return sprintf(page, "%lu\n", mddev->bitmap_info.chunksize);
-}
-
-static ssize_t
-chunksize_store(struct mddev *mddev, const char *buf, size_t len)
-{
- /* Can only be changed when no bitmap is active */
- int rv;
- unsigned long csize;
- if (mddev->bitmap)
- return -EBUSY;
- rv = kstrtoul(buf, 10, &csize);
- if (rv)
- return rv;
- if (csize < 512 ||
- !is_power_of_2(csize))
- return -EINVAL;
- mddev->bitmap_info.chunksize = csize;
- return len;
-}
-
-static struct md_sysfs_entry bitmap_chunksize =
-__ATTR(chunksize, S_IRUGO|S_IWUSR, chunksize_show, chunksize_store);
-
-static ssize_t metadata_show(struct mddev *mddev, char *page)
-{
- if (mddev_is_clustered(mddev))
- return sprintf(page, "clustered\n");
- return sprintf(page, "%s\n", (mddev->bitmap_info.external
- ? "external" : "internal"));
-}
-
-static ssize_t metadata_store(struct mddev *mddev, const char *buf, size_t len)
-{
- if (mddev->bitmap ||
- mddev->bitmap_info.file ||
- mddev->bitmap_info.offset)
- return -EBUSY;
- if (strncmp(buf, "external", 8) == 0)
- mddev->bitmap_info.external = 1;
- else if ((strncmp(buf, "internal", 8) == 0) ||
- (strncmp(buf, "clustered", 9) == 0))
- mddev->bitmap_info.external = 0;
- else
- return -EINVAL;
- return len;
-}
-
-static struct md_sysfs_entry bitmap_metadata =
-__ATTR(metadata, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
-
-static ssize_t can_clear_show(struct mddev *mddev, char *page)
-{
- int len;
- spin_lock(&mddev->lock);
- if (mddev->bitmap)
- len = sprintf(page, "%s\n", (mddev->bitmap->need_sync ?
- "false" : "true"));
- else
- len = sprintf(page, "\n");
- spin_unlock(&mddev->lock);
- return len;
-}
-
-static ssize_t can_clear_store(struct mddev *mddev, const char *buf, size_t len)
-{
- if (mddev->bitmap == NULL)
- return -ENOENT;
- if (strncmp(buf, "false", 5) == 0)
- mddev->bitmap->need_sync = 1;
- else if (strncmp(buf, "true", 4) == 0) {
- if (mddev->degraded)
- return -EBUSY;
- mddev->bitmap->need_sync = 0;
- } else
- return -EINVAL;
- return len;
-}
-
-static struct md_sysfs_entry bitmap_can_clear =
-__ATTR(can_clear, S_IRUGO|S_IWUSR, can_clear_show, can_clear_store);
-
-static ssize_t
-behind_writes_used_show(struct mddev *mddev, char *page)
-{
- ssize_t ret;
- spin_lock(&mddev->lock);
- if (mddev->bitmap == NULL)
- ret = sprintf(page, "0\n");
- else
- ret = sprintf(page, "%lu\n",
- mddev->bitmap->behind_writes_used);
- spin_unlock(&mddev->lock);
- return ret;
-}
-
-static ssize_t
-behind_writes_used_reset(struct mddev *mddev, const char *buf, size_t len)
-{
- if (mddev->bitmap)
- mddev->bitmap->behind_writes_used = 0;
- return len;
-}
-
-static struct md_sysfs_entry max_backlog_used =
-__ATTR(max_backlog_used, S_IRUGO | S_IWUSR,
- behind_writes_used_show, behind_writes_used_reset);
-
-static struct attribute *md_bitmap_attrs[] = {
- &bitmap_location.attr,
- &bitmap_space.attr,
- &bitmap_timeout.attr,
- &bitmap_backlog.attr,
- &bitmap_chunksize.attr,
- &bitmap_metadata.attr,
- &bitmap_can_clear.attr,
- &max_backlog_used.attr,
- NULL
-};
-struct attribute_group md_bitmap_group = {
- .name = "bitmap",
- .attrs = md_bitmap_attrs,
-};
-
+++ /dev/null
-/*
- * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
- *
- * additions: Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
- */
-#ifndef BITMAP_H
-#define BITMAP_H 1
-
-#define BITMAP_MAJOR_LO 3
-/* version 4 insists the bitmap is in little-endian order
- * with version 3, it is host-endian which is non-portable
- * Version 5 is currently set only for clustered devices
- */
-#define BITMAP_MAJOR_HI 4
-#define BITMAP_MAJOR_CLUSTERED 5
-#define BITMAP_MAJOR_HOSTENDIAN 3
-
-/*
- * in-memory bitmap:
- *
- * Use 16 bit block counters to track pending writes to each "chunk".
- * The 2 high order bits are special-purpose, the first is a flag indicating
- * whether a resync is needed. The second is a flag indicating whether a
- * resync is active.
- * This means that the counter is actually 14 bits:
- *
- * +--------+--------+------------------------------------------------+
- * | resync | resync | counter |
- * | needed | active | |
- * | (0-1) | (0-1) | (0-16383) |
- * +--------+--------+------------------------------------------------+
- *
- * The "resync needed" bit is set when:
- * a '1' bit is read from storage at startup.
- * a write request fails on some drives
- * a resync is aborted on a chunk with 'resync active' set
- * It is cleared (and resync-active set) when a resync starts across all drives
- * of the chunk.
- *
- *
- * The "resync active" bit is set when:
- * a resync is started on all drives, and resync_needed is set.
- * resync_needed will be cleared (as long as resync_active wasn't already set).
- * It is cleared when a resync completes.
- *
- * The counter counts pending write requests, plus the on-disk bit.
- * When the counter is '1' and the resync bits are clear, the on-disk
- * bit can be cleared as well, thus setting the counter to 0.
- * When we set a bit, or in the counter (to start a write), if the fields is
- * 0, we first set the disk bit and set the counter to 1.
- *
- * If the counter is 0, the on-disk bit is clear and the stripe is clean
- * Anything that dirties the stripe pushes the counter to 2 (at least)
- * and sets the on-disk bit (lazily).
- * If a periodic sweep find the counter at 2, it is decremented to 1.
- * If the sweep find the counter at 1, the on-disk bit is cleared and the
- * counter goes to zero.
- *
- * Also, we'll hijack the "map" pointer itself and use it as two 16 bit block
- * counters as a fallback when "page" memory cannot be allocated:
- *
- * Normal case (page memory allocated):
- *
- * page pointer (32-bit)
- *
- * [ ] ------+
- * |
- * +-------> [ ][ ]..[ ] (4096 byte page == 2048 counters)
- * c1 c2 c2048
- *
- * Hijacked case (page memory allocation failed):
- *
- * hijacked page pointer (32-bit)
- *
- * [ ][ ] (no page memory allocated)
- * counter #1 (16-bit) counter #2 (16-bit)
- *
- */
-
-#ifdef __KERNEL__
-
-#define PAGE_BITS (PAGE_SIZE << 3)
-#define PAGE_BIT_SHIFT (PAGE_SHIFT + 3)
-
-typedef __u16 bitmap_counter_t;
-#define COUNTER_BITS 16
-#define COUNTER_BIT_SHIFT 4
-#define COUNTER_BYTE_SHIFT (COUNTER_BIT_SHIFT - 3)
-
-#define NEEDED_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 1)))
-#define RESYNC_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 2)))
-#define COUNTER_MAX ((bitmap_counter_t) RESYNC_MASK - 1)
-#define NEEDED(x) (((bitmap_counter_t) x) & NEEDED_MASK)
-#define RESYNC(x) (((bitmap_counter_t) x) & RESYNC_MASK)
-#define COUNTER(x) (((bitmap_counter_t) x) & COUNTER_MAX)
-
-/* how many counters per page? */
-#define PAGE_COUNTER_RATIO (PAGE_BITS / COUNTER_BITS)
-/* same, except a shift value for more efficient bitops */
-#define PAGE_COUNTER_SHIFT (PAGE_BIT_SHIFT - COUNTER_BIT_SHIFT)
-/* same, except a mask value for more efficient bitops */
-#define PAGE_COUNTER_MASK (PAGE_COUNTER_RATIO - 1)
-
-#define BITMAP_BLOCK_SHIFT 9
-
-#endif
-
-/*
- * bitmap structures:
- */
-
-#define BITMAP_MAGIC 0x6d746962
-
-/* use these for bitmap->flags and bitmap->sb->state bit-fields */
-enum bitmap_state {
- BITMAP_STALE = 1, /* the bitmap file is out of date or had -EIO */
- BITMAP_WRITE_ERROR = 2, /* A write error has occurred */
- BITMAP_HOSTENDIAN =15,
-};
-
-/* the superblock at the front of the bitmap file -- little endian */
-typedef struct bitmap_super_s {
- __le32 magic; /* 0 BITMAP_MAGIC */
- __le32 version; /* 4 the bitmap major for now, could change... */
- __u8 uuid[16]; /* 8 128 bit uuid - must match md device uuid */
- __le64 events; /* 24 event counter for the bitmap (1)*/
- __le64 events_cleared;/*32 event counter when last bit cleared (2) */
- __le64 sync_size; /* 40 the size of the md device's sync range(3) */
- __le32 state; /* 48 bitmap state information */
- __le32 chunksize; /* 52 the bitmap chunk size in bytes */
- __le32 daemon_sleep; /* 56 seconds between disk flushes */
- __le32 write_behind; /* 60 number of outstanding write-behind writes */
- __le32 sectors_reserved; /* 64 number of 512-byte sectors that are
- * reserved for the bitmap. */
- __le32 nodes; /* 68 the maximum number of nodes in cluster. */
- __u8 cluster_name[64]; /* 72 cluster name to which this md belongs */
- __u8 pad[256 - 136]; /* set to zero */
-} bitmap_super_t;
-
-/* notes:
- * (1) This event counter is updated before the eventcounter in the md superblock
- * When a bitmap is loaded, it is only accepted if this event counter is equal
- * to, or one greater than, the event counter in the superblock.
- * (2) This event counter is updated when the other one is *if*and*only*if* the
- * array is not degraded. As bits are not cleared when the array is degraded,
- * this represents the last time that any bits were cleared.
- * If a device is being added that has an event count with this value or
- * higher, it is accepted as conforming to the bitmap.
- * (3)This is the number of sectors represented by the bitmap, and is the range that
- * resync happens across. For raid1 and raid5/6 it is the size of individual
- * devices. For raid10 it is the size of the array.
- */
-
-#ifdef __KERNEL__
-
-/* the in-memory bitmap is represented by bitmap_pages */
-struct bitmap_page {
- /*
- * map points to the actual memory page
- */
- char *map;
- /*
- * in emergencies (when map cannot be alloced), hijack the map
- * pointer and use it as two counters itself
- */
- unsigned int hijacked:1;
- /*
- * If any counter in this page is '1' or '2' - and so could be
- * cleared then that page is marked as 'pending'
- */
- unsigned int pending:1;
- /*
- * count of dirty bits on the page
- */
- unsigned int count:30;
-};
-
-/* the main bitmap structure - one per mddev */
-struct bitmap {
-
- struct bitmap_counts {
- spinlock_t lock;
- struct bitmap_page *bp;
- unsigned long pages; /* total number of pages
- * in the bitmap */
- unsigned long missing_pages; /* number of pages
- * not yet allocated */
- unsigned long chunkshift; /* chunksize = 2^chunkshift
- * (for bitops) */
- unsigned long chunks; /* Total number of data
- * chunks for the array */
- } counts;
-
- struct mddev *mddev; /* the md device that the bitmap is for */
-
- __u64 events_cleared;
- int need_sync;
-
- struct bitmap_storage {
- struct file *file; /* backing disk file */
- struct page *sb_page; /* cached copy of the bitmap
- * file superblock */
- struct page **filemap; /* list of cache pages for
- * the file */
- unsigned long *filemap_attr; /* attributes associated
- * w/ filemap pages */
- unsigned long file_pages; /* number of pages in the file*/
- unsigned long bytes; /* total bytes in the bitmap */
- } storage;
-
- unsigned long flags;
-
- int allclean;
-
- atomic_t behind_writes;
- unsigned long behind_writes_used; /* highest actual value at runtime */
-
- /*
- * the bitmap daemon - periodically wakes up and sweeps the bitmap
- * file, cleaning up bits and flushing out pages to disk as necessary
- */
- unsigned long daemon_lastrun; /* jiffies of last run */
- unsigned long last_end_sync; /* when we lasted called end_sync to
- * update bitmap with resync progress */
-
- atomic_t pending_writes; /* pending writes to the bitmap file */
- wait_queue_head_t write_wait;
- wait_queue_head_t overflow_wait;
- wait_queue_head_t behind_wait;
-
- struct kernfs_node *sysfs_can_clear;
- int cluster_slot; /* Slot offset for clustered env */
-};
-
-/* the bitmap API */
-
-/* these are used only by md/bitmap */
-struct bitmap *bitmap_create(struct mddev *mddev, int slot);
-int bitmap_load(struct mddev *mddev);
-void bitmap_flush(struct mddev *mddev);
-void bitmap_destroy(struct mddev *mddev);
-
-void bitmap_print_sb(struct bitmap *bitmap);
-void bitmap_update_sb(struct bitmap *bitmap);
-void bitmap_status(struct seq_file *seq, struct bitmap *bitmap);
-
-int bitmap_setallbits(struct bitmap *bitmap);
-void bitmap_write_all(struct bitmap *bitmap);
-
-void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e);
-
-/* these are exported */
-int bitmap_startwrite(struct bitmap *bitmap, sector_t offset,
- unsigned long sectors, int behind);
-void bitmap_endwrite(struct bitmap *bitmap, sector_t offset,
- unsigned long sectors, int success, int behind);
-int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int degraded);
-void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted);
-void bitmap_close_sync(struct bitmap *bitmap);
-void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector, bool force);
-void bitmap_sync_with_cluster(struct mddev *mddev,
- sector_t old_lo, sector_t old_hi,
- sector_t new_lo, sector_t new_hi);
-
-void bitmap_unplug(struct bitmap *bitmap);
-void bitmap_daemon_work(struct mddev *mddev);
-
-int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
- int chunksize, int init);
-struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot);
-int bitmap_copy_from_slot(struct mddev *mddev, int slot,
- sector_t *lo, sector_t *hi, bool clear_bits);
-void bitmap_free(struct bitmap *bitmap);
-void bitmap_wait_behind_writes(struct mddev *mddev);
-#endif
-
-#endif
#include "raid1.h"
#include "raid5.h"
#include "raid10.h"
-#include "bitmap.h"
+#include "md-bitmap.h"
#include <linux/device-mapper.h>
+++ /dev/null
-/*
- * faulty.c : Multiple Devices driver for Linux
- *
- * Copyright (C) 2004 Neil Brown
- *
- * fautly-device-simulator personality for md
- *
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * You should have received a copy of the GNU General Public License
- * (for example /usr/src/linux/COPYING); if not, write to the Free
- * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-
-/*
- * The "faulty" personality causes some requests to fail.
- *
- * Possible failure modes are:
- * reads fail "randomly" but succeed on retry
- * writes fail "randomly" but succeed on retry
- * reads for some address fail and then persist until a write
- * reads for some address fail and then persist irrespective of write
- * writes for some address fail and persist
- * all writes fail
- *
- * Different modes can be active at a time, but only
- * one can be set at array creation. Others can be added later.
- * A mode can be one-shot or recurrent with the recurrence being
- * once in every N requests.
- * The bottom 5 bits of the "layout" indicate the mode. The
- * remainder indicate a period, or 0 for one-shot.
- *
- * There is an implementation limit on the number of concurrently
- * persisting-faulty blocks. When a new fault is requested that would
- * exceed the limit, it is ignored.
- * All current faults can be clear using a layout of "0".
- *
- * Requests are always sent to the device. If they are to fail,
- * we clone the bio and insert a new b_end_io into the chain.
- */
-
-#define WriteTransient 0
-#define ReadTransient 1
-#define WritePersistent 2
-#define ReadPersistent 3
-#define WriteAll 4 /* doesn't go to device */
-#define ReadFixable 5
-#define Modes 6
-
-#define ClearErrors 31
-#define ClearFaults 30
-
-#define AllPersist 100 /* internal use only */
-#define NoPersist 101
-
-#define ModeMask 0x1f
-#define ModeShift 5
-
-#define MaxFault 50
-#include <linux/blkdev.h>
-#include <linux/module.h>
-#include <linux/raid/md_u.h>
-#include <linux/slab.h>
-#include "md.h"
-#include <linux/seq_file.h>
-
-
-static void faulty_fail(struct bio *bio)
-{
- struct bio *b = bio->bi_private;
-
- b->bi_iter.bi_size = bio->bi_iter.bi_size;
- b->bi_iter.bi_sector = bio->bi_iter.bi_sector;
-
- bio_put(bio);
-
- bio_io_error(b);
-}
-
-struct faulty_conf {
- int period[Modes];
- atomic_t counters[Modes];
- sector_t faults[MaxFault];
- int modes[MaxFault];
- int nfaults;
- struct md_rdev *rdev;
-};
-
-static int check_mode(struct faulty_conf *conf, int mode)
-{
- if (conf->period[mode] == 0 &&
- atomic_read(&conf->counters[mode]) <= 0)
- return 0; /* no failure, no decrement */
-
-
- if (atomic_dec_and_test(&conf->counters[mode])) {
- if (conf->period[mode])
- atomic_set(&conf->counters[mode], conf->period[mode]);
- return 1;
- }
- return 0;
-}
-
-static int check_sector(struct faulty_conf *conf, sector_t start, sector_t end, int dir)
-{
- /* If we find a ReadFixable sector, we fix it ... */
- int i;
- for (i=0; i<conf->nfaults; i++)
- if (conf->faults[i] >= start &&
- conf->faults[i] < end) {
- /* found it ... */
- switch (conf->modes[i] * 2 + dir) {
- case WritePersistent*2+WRITE: return 1;
- case ReadPersistent*2+READ: return 1;
- case ReadFixable*2+READ: return 1;
- case ReadFixable*2+WRITE:
- conf->modes[i] = NoPersist;
- return 0;
- case AllPersist*2+READ:
- case AllPersist*2+WRITE: return 1;
- default:
- return 0;
- }
- }
- return 0;
-}
-
-static void add_sector(struct faulty_conf *conf, sector_t start, int mode)
-{
- int i;
- int n = conf->nfaults;
- for (i=0; i<conf->nfaults; i++)
- if (conf->faults[i] == start) {
- switch(mode) {
- case NoPersist: conf->modes[i] = mode; return;
- case WritePersistent:
- if (conf->modes[i] == ReadPersistent ||
- conf->modes[i] == ReadFixable)
- conf->modes[i] = AllPersist;
- else
- conf->modes[i] = WritePersistent;
- return;
- case ReadPersistent:
- if (conf->modes[i] == WritePersistent)
- conf->modes[i] = AllPersist;
- else
- conf->modes[i] = ReadPersistent;
- return;
- case ReadFixable:
- if (conf->modes[i] == WritePersistent ||
- conf->modes[i] == ReadPersistent)
- conf->modes[i] = AllPersist;
- else
- conf->modes[i] = ReadFixable;
- return;
- }
- } else if (conf->modes[i] == NoPersist)
- n = i;
-
- if (n >= MaxFault)
- return;
- conf->faults[n] = start;
- conf->modes[n] = mode;
- if (conf->nfaults == n)
- conf->nfaults = n+1;
-}
-
-static bool faulty_make_request(struct mddev *mddev, struct bio *bio)
-{
- struct faulty_conf *conf = mddev->private;
- int failit = 0;
-
- if (bio_data_dir(bio) == WRITE) {
- /* write request */
- if (atomic_read(&conf->counters[WriteAll])) {
- /* special case - don't decrement, don't generic_make_request,
- * just fail immediately
- */
- bio_io_error(bio);
- return true;
- }
-
- if (check_sector(conf, bio->bi_iter.bi_sector,
- bio_end_sector(bio), WRITE))
- failit = 1;
- if (check_mode(conf, WritePersistent)) {
- add_sector(conf, bio->bi_iter.bi_sector,
- WritePersistent);
- failit = 1;
- }
- if (check_mode(conf, WriteTransient))
- failit = 1;
- } else {
- /* read request */
- if (check_sector(conf, bio->bi_iter.bi_sector,
- bio_end_sector(bio), READ))
- failit = 1;
- if (check_mode(conf, ReadTransient))
- failit = 1;
- if (check_mode(conf, ReadPersistent)) {
- add_sector(conf, bio->bi_iter.bi_sector,
- ReadPersistent);
- failit = 1;
- }
- if (check_mode(conf, ReadFixable)) {
- add_sector(conf, bio->bi_iter.bi_sector,
- ReadFixable);
- failit = 1;
- }
- }
- if (failit) {
- struct bio *b = bio_clone_fast(bio, GFP_NOIO, mddev->bio_set);
-
- bio_set_dev(b, conf->rdev->bdev);
- b->bi_private = bio;
- b->bi_end_io = faulty_fail;
- bio = b;
- } else
- bio_set_dev(bio, conf->rdev->bdev);
-
- generic_make_request(bio);
- return true;
-}
-
-static void faulty_status(struct seq_file *seq, struct mddev *mddev)
-{
- struct faulty_conf *conf = mddev->private;
- int n;
-
- if ((n=atomic_read(&conf->counters[WriteTransient])) != 0)
- seq_printf(seq, " WriteTransient=%d(%d)",
- n, conf->period[WriteTransient]);
-
- if ((n=atomic_read(&conf->counters[ReadTransient])) != 0)
- seq_printf(seq, " ReadTransient=%d(%d)",
- n, conf->period[ReadTransient]);
-
- if ((n=atomic_read(&conf->counters[WritePersistent])) != 0)
- seq_printf(seq, " WritePersistent=%d(%d)",
- n, conf->period[WritePersistent]);
-
- if ((n=atomic_read(&conf->counters[ReadPersistent])) != 0)
- seq_printf(seq, " ReadPersistent=%d(%d)",
- n, conf->period[ReadPersistent]);
-
-
- if ((n=atomic_read(&conf->counters[ReadFixable])) != 0)
- seq_printf(seq, " ReadFixable=%d(%d)",
- n, conf->period[ReadFixable]);
-
- if ((n=atomic_read(&conf->counters[WriteAll])) != 0)
- seq_printf(seq, " WriteAll");
-
- seq_printf(seq, " nfaults=%d", conf->nfaults);
-}
-
-
-static int faulty_reshape(struct mddev *mddev)
-{
- int mode = mddev->new_layout & ModeMask;
- int count = mddev->new_layout >> ModeShift;
- struct faulty_conf *conf = mddev->private;
-
- if (mddev->new_layout < 0)
- return 0;
-
- /* new layout */
- if (mode == ClearFaults)
- conf->nfaults = 0;
- else if (mode == ClearErrors) {
- int i;
- for (i=0 ; i < Modes ; i++) {
- conf->period[i] = 0;
- atomic_set(&conf->counters[i], 0);
- }
- } else if (mode < Modes) {
- conf->period[mode] = count;
- if (!count) count++;
- atomic_set(&conf->counters[mode], count);
- } else
- return -EINVAL;
- mddev->new_layout = -1;
- mddev->layout = -1; /* makes sure further changes come through */
- return 0;
-}
-
-static sector_t faulty_size(struct mddev *mddev, sector_t sectors, int raid_disks)
-{
- WARN_ONCE(raid_disks,
- "%s does not support generic reshape\n", __func__);
-
- if (sectors == 0)
- return mddev->dev_sectors;
-
- return sectors;
-}
-
-static int faulty_run(struct mddev *mddev)
-{
- struct md_rdev *rdev;
- int i;
- struct faulty_conf *conf;
-
- if (md_check_no_bitmap(mddev))
- return -EINVAL;
-
- conf = kmalloc(sizeof(*conf), GFP_KERNEL);
- if (!conf)
- return -ENOMEM;
-
- for (i=0; i<Modes; i++) {
- atomic_set(&conf->counters[i], 0);
- conf->period[i] = 0;
- }
- conf->nfaults = 0;
-
- rdev_for_each(rdev, mddev) {
- conf->rdev = rdev;
- disk_stack_limits(mddev->gendisk, rdev->bdev,
- rdev->data_offset << 9);
- }
-
- md_set_array_sectors(mddev, faulty_size(mddev, 0, 0));
- mddev->private = conf;
-
- faulty_reshape(mddev);
-
- return 0;
-}
-
-static void faulty_free(struct mddev *mddev, void *priv)
-{
- struct faulty_conf *conf = priv;
-
- kfree(conf);
-}
-
-static struct md_personality faulty_personality =
-{
- .name = "faulty",
- .level = LEVEL_FAULTY,
- .owner = THIS_MODULE,
- .make_request = faulty_make_request,
- .run = faulty_run,
- .free = faulty_free,
- .status = faulty_status,
- .check_reshape = faulty_reshape,
- .size = faulty_size,
-};
-
-static int __init raid_init(void)
-{
- return register_md_personality(&faulty_personality);
-}
-
-static void raid_exit(void)
-{
- unregister_md_personality(&faulty_personality);
-}
-
-module_init(raid_init);
-module_exit(raid_exit);
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Fault injection personality for MD");
-MODULE_ALIAS("md-personality-10"); /* faulty */
-MODULE_ALIAS("md-faulty");
-MODULE_ALIAS("md-level--5");
+++ /dev/null
-/*
- linear.c : Multiple Devices driver for Linux
- Copyright (C) 1994-96 Marc ZYNGIER
- <zyngier@ufr-info-p7.ibp.fr> or
- <maz@gloups.fdn.fr>
-
- Linear mode management functions.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
- any later version.
-
- You should have received a copy of the GNU General Public License
- (for example /usr/src/linux/COPYING); if not, write to the Free
- Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-#include <linux/blkdev.h>
-#include <linux/raid/md_u.h>
-#include <linux/seq_file.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <trace/events/block.h>
-#include "md.h"
-#include "linear.h"
-
-/*
- * find which device holds a particular offset
- */
-static inline struct dev_info *which_dev(struct mddev *mddev, sector_t sector)
-{
- int lo, mid, hi;
- struct linear_conf *conf;
-
- lo = 0;
- hi = mddev->raid_disks - 1;
- conf = mddev->private;
-
- /*
- * Binary Search
- */
-
- while (hi > lo) {
-
- mid = (hi + lo) / 2;
- if (sector < conf->disks[mid].end_sector)
- hi = mid;
- else
- lo = mid + 1;
- }
-
- return conf->disks + lo;
-}
-
-/*
- * In linear_congested() conf->raid_disks is used as a copy of
- * mddev->raid_disks to iterate conf->disks[], because conf->raid_disks
- * and conf->disks[] are created in linear_conf(), they are always
- * consitent with each other, but mddev->raid_disks does not.
- */
-static int linear_congested(struct mddev *mddev, int bits)
-{
- struct linear_conf *conf;
- int i, ret = 0;
-
- rcu_read_lock();
- conf = rcu_dereference(mddev->private);
-
- for (i = 0; i < conf->raid_disks && !ret ; i++) {
- struct request_queue *q = bdev_get_queue(conf->disks[i].rdev->bdev);
- ret |= bdi_congested(q->backing_dev_info, bits);
- }
-
- rcu_read_unlock();
- return ret;
-}
-
-static sector_t linear_size(struct mddev *mddev, sector_t sectors, int raid_disks)
-{
- struct linear_conf *conf;
- sector_t array_sectors;
-
- conf = mddev->private;
- WARN_ONCE(sectors || raid_disks,
- "%s does not support generic reshape\n", __func__);
- array_sectors = conf->array_sectors;
-
- return array_sectors;
-}
-
-static struct linear_conf *linear_conf(struct mddev *mddev, int raid_disks)
-{
- struct linear_conf *conf;
- struct md_rdev *rdev;
- int i, cnt;
- bool discard_supported = false;
-
- conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(struct dev_info),
- GFP_KERNEL);
- if (!conf)
- return NULL;
-
- cnt = 0;
- conf->array_sectors = 0;
-
- rdev_for_each(rdev, mddev) {
- int j = rdev->raid_disk;
- struct dev_info *disk = conf->disks + j;
- sector_t sectors;
-
- if (j < 0 || j >= raid_disks || disk->rdev) {
- pr_warn("md/linear:%s: disk numbering problem. Aborting!\n",
- mdname(mddev));
- goto out;
- }
-
- disk->rdev = rdev;
- if (mddev->chunk_sectors) {
- sectors = rdev->sectors;
- sector_div(sectors, mddev->chunk_sectors);
- rdev->sectors = sectors * mddev->chunk_sectors;
- }
-
- disk_stack_limits(mddev->gendisk, rdev->bdev,
- rdev->data_offset << 9);
-
- conf->array_sectors += rdev->sectors;
- cnt++;
-
- if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
- discard_supported = true;
- }
- if (cnt != raid_disks) {
- pr_warn("md/linear:%s: not enough drives present. Aborting!\n",
- mdname(mddev));
- goto out;
- }
-
- if (!discard_supported)
- queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
- else
- queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
-
- /*
- * Here we calculate the device offsets.
- */
- conf->disks[0].end_sector = conf->disks[0].rdev->sectors;
-
- for (i = 1; i < raid_disks; i++)
- conf->disks[i].end_sector =
- conf->disks[i-1].end_sector +
- conf->disks[i].rdev->sectors;
-
- /*
- * conf->raid_disks is copy of mddev->raid_disks. The reason to
- * keep a copy of mddev->raid_disks in struct linear_conf is,
- * mddev->raid_disks may not be consistent with pointers number of
- * conf->disks[] when it is updated in linear_add() and used to
- * iterate old conf->disks[] earray in linear_congested().
- * Here conf->raid_disks is always consitent with number of
- * pointers in conf->disks[] array, and mddev->private is updated
- * with rcu_assign_pointer() in linear_addr(), such race can be
- * avoided.
- */
- conf->raid_disks = raid_disks;
-
- return conf;
-
-out:
- kfree(conf);
- return NULL;
-}
-
-static int linear_run (struct mddev *mddev)
-{
- struct linear_conf *conf;
- int ret;
-
- if (md_check_no_bitmap(mddev))
- return -EINVAL;
- conf = linear_conf(mddev, mddev->raid_disks);
-
- if (!conf)
- return 1;
- mddev->private = conf;
- md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
-
- ret = md_integrity_register(mddev);
- if (ret) {
- kfree(conf);
- mddev->private = NULL;
- }
- return ret;
-}
-
-static int linear_add(struct mddev *mddev, struct md_rdev *rdev)
-{
- /* Adding a drive to a linear array allows the array to grow.
- * It is permitted if the new drive has a matching superblock
- * already on it, with raid_disk equal to raid_disks.
- * It is achieved by creating a new linear_private_data structure
- * and swapping it in in-place of the current one.
- * The current one is never freed until the array is stopped.
- * This avoids races.
- */
- struct linear_conf *newconf, *oldconf;
-
- if (rdev->saved_raid_disk != mddev->raid_disks)
- return -EINVAL;
-
- rdev->raid_disk = rdev->saved_raid_disk;
- rdev->saved_raid_disk = -1;
-
- newconf = linear_conf(mddev,mddev->raid_disks+1);
-
- if (!newconf)
- return -ENOMEM;
-
- /* newconf->raid_disks already keeps a copy of * the increased
- * value of mddev->raid_disks, WARN_ONCE() is just used to make
- * sure of this. It is possible that oldconf is still referenced
- * in linear_congested(), therefore kfree_rcu() is used to free
- * oldconf until no one uses it anymore.
- */
- mddev_suspend(mddev);
- oldconf = rcu_dereference_protected(mddev->private,
- lockdep_is_held(&mddev->reconfig_mutex));
- mddev->raid_disks++;
- WARN_ONCE(mddev->raid_disks != newconf->raid_disks,
- "copied raid_disks doesn't match mddev->raid_disks");
- rcu_assign_pointer(mddev->private, newconf);
- md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
- set_capacity(mddev->gendisk, mddev->array_sectors);
- mddev_resume(mddev);
- revalidate_disk(mddev->gendisk);
- kfree_rcu(oldconf, rcu);
- return 0;
-}
-
-static void linear_free(struct mddev *mddev, void *priv)
-{
- struct linear_conf *conf = priv;
-
- kfree(conf);
-}
-
-static bool linear_make_request(struct mddev *mddev, struct bio *bio)
-{
- char b[BDEVNAME_SIZE];
- struct dev_info *tmp_dev;
- sector_t start_sector, end_sector, data_offset;
- sector_t bio_sector = bio->bi_iter.bi_sector;
-
- if (unlikely(bio->bi_opf & REQ_PREFLUSH)) {
- md_flush_request(mddev, bio);
- return true;
- }
-
- tmp_dev = which_dev(mddev, bio_sector);
- start_sector = tmp_dev->end_sector - tmp_dev->rdev->sectors;
- end_sector = tmp_dev->end_sector;
- data_offset = tmp_dev->rdev->data_offset;
-
- if (unlikely(bio_sector >= end_sector ||
- bio_sector < start_sector))
- goto out_of_bounds;
-
- if (unlikely(bio_end_sector(bio) > end_sector)) {
- /* This bio crosses a device boundary, so we have to split it */
- struct bio *split = bio_split(bio, end_sector - bio_sector,
- GFP_NOIO, mddev->bio_set);
- bio_chain(split, bio);
- generic_make_request(bio);
- bio = split;
- }
-
- bio_set_dev(bio, tmp_dev->rdev->bdev);
- bio->bi_iter.bi_sector = bio->bi_iter.bi_sector -
- start_sector + data_offset;
-
- if (unlikely((bio_op(bio) == REQ_OP_DISCARD) &&
- !blk_queue_discard(bio->bi_disk->queue))) {
- /* Just ignore it */
- bio_endio(bio);
- } else {
- if (mddev->gendisk)
- trace_block_bio_remap(bio->bi_disk->queue,
- bio, disk_devt(mddev->gendisk),
- bio_sector);
- mddev_check_writesame(mddev, bio);
- mddev_check_write_zeroes(mddev, bio);
- generic_make_request(bio);
- }
- return true;
-
-out_of_bounds:
- pr_err("md/linear:%s: make_request: Sector %llu out of bounds on dev %s: %llu sectors, offset %llu\n",
- mdname(mddev),
- (unsigned long long)bio->bi_iter.bi_sector,
- bdevname(tmp_dev->rdev->bdev, b),
- (unsigned long long)tmp_dev->rdev->sectors,
- (unsigned long long)start_sector);
- bio_io_error(bio);
- return true;
-}
-
-static void linear_status (struct seq_file *seq, struct mddev *mddev)
-{
- seq_printf(seq, " %dk rounding", mddev->chunk_sectors / 2);
-}
-
-static void linear_quiesce(struct mddev *mddev, int state)
-{
-}
-
-static struct md_personality linear_personality =
-{
- .name = "linear",
- .level = LEVEL_LINEAR,
- .owner = THIS_MODULE,
- .make_request = linear_make_request,
- .run = linear_run,
- .free = linear_free,
- .status = linear_status,
- .hot_add_disk = linear_add,
- .size = linear_size,
- .quiesce = linear_quiesce,
- .congested = linear_congested,
-};
-
-static int __init linear_init (void)
-{
- return register_md_personality (&linear_personality);
-}
-
-static void linear_exit (void)
-{
- unregister_md_personality (&linear_personality);
-}
-
-module_init(linear_init);
-module_exit(linear_exit);
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Linear device concatenation personality for MD");
-MODULE_ALIAS("md-personality-1"); /* LINEAR - deprecated*/
-MODULE_ALIAS("md-linear");
-MODULE_ALIAS("md-level--1");
+++ /dev/null
-#ifndef _LINEAR_H
-#define _LINEAR_H
-
-struct dev_info {
- struct md_rdev *rdev;
- sector_t end_sector;
-};
-
-struct linear_conf
-{
- struct rcu_head rcu;
- sector_t array_sectors;
- int raid_disks; /* a copy of mddev->raid_disks */
- struct dev_info disks[0];
-};
-#endif
--- /dev/null
+/*
+ * bitmap.c two-level bitmap (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
+ *
+ * bitmap_create - sets up the bitmap structure
+ * bitmap_destroy - destroys the bitmap structure
+ *
+ * additions, Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.:
+ * - added disk storage for bitmap
+ * - changes to allow various bitmap chunk sizes
+ */
+
+/*
+ * Still to do:
+ *
+ * flush after percent set rather than just time based. (maybe both).
+ */
+
+#include <linux/blkdev.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/sched.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <linux/mount.h>
+#include <linux/buffer_head.h>
+#include <linux/seq_file.h>
+#include <trace/events/block.h>
+#include "md.h"
+#include "md-bitmap.h"
+
+static inline char *bmname(struct bitmap *bitmap)
+{
+ return bitmap->mddev ? mdname(bitmap->mddev) : "mdX";
+}
+
+/*
+ * check a page and, if necessary, allocate it (or hijack it if the alloc fails)
+ *
+ * 1) check to see if this page is allocated, if it's not then try to alloc
+ * 2) if the alloc fails, set the page's hijacked flag so we'll use the
+ * page pointer directly as a counter
+ *
+ * if we find our page, we increment the page's refcount so that it stays
+ * allocated while we're using it
+ */
+static int bitmap_checkpage(struct bitmap_counts *bitmap,
+ unsigned long page, int create, int no_hijack)
+__releases(bitmap->lock)
+__acquires(bitmap->lock)
+{
+ unsigned char *mappage;
+
+ if (page >= bitmap->pages) {
+ /* This can happen if bitmap_start_sync goes beyond
+ * End-of-device while looking for a whole page.
+ * It is harmless.
+ */
+ return -EINVAL;
+ }
+
+ if (bitmap->bp[page].hijacked) /* it's hijacked, don't try to alloc */
+ return 0;
+
+ if (bitmap->bp[page].map) /* page is already allocated, just return */
+ return 0;
+
+ if (!create)
+ return -ENOENT;
+
+ /* this page has not been allocated yet */
+
+ spin_unlock_irq(&bitmap->lock);
+ /* It is possible that this is being called inside a
+ * prepare_to_wait/finish_wait loop from raid5c:make_request().
+ * In general it is not permitted to sleep in that context as it
+ * can cause the loop to spin freely.
+ * That doesn't apply here as we can only reach this point
+ * once with any loop.
+ * When this function completes, either bp[page].map or
+ * bp[page].hijacked. In either case, this function will
+ * abort before getting to this point again. So there is
+ * no risk of a free-spin, and so it is safe to assert
+ * that sleeping here is allowed.
+ */
+ sched_annotate_sleep();
+ mappage = kzalloc(PAGE_SIZE, GFP_NOIO);
+ spin_lock_irq(&bitmap->lock);
+
+ if (mappage == NULL) {
+ pr_debug("md/bitmap: map page allocation failed, hijacking\n");
+ /* We don't support hijack for cluster raid */
+ if (no_hijack)
+ return -ENOMEM;
+ /* failed - set the hijacked flag so that we can use the
+ * pointer as a counter */
+ if (!bitmap->bp[page].map)
+ bitmap->bp[page].hijacked = 1;
+ } else if (bitmap->bp[page].map ||
+ bitmap->bp[page].hijacked) {
+ /* somebody beat us to getting the page */
+ kfree(mappage);
+ } else {
+
+ /* no page was in place and we have one, so install it */
+
+ bitmap->bp[page].map = mappage;
+ bitmap->missing_pages--;
+ }
+ return 0;
+}
+
+/* if page is completely empty, put it back on the free list, or dealloc it */
+/* if page was hijacked, unmark the flag so it might get alloced next time */
+/* Note: lock should be held when calling this */
+static void bitmap_checkfree(struct bitmap_counts *bitmap, unsigned long page)
+{
+ char *ptr;
+
+ if (bitmap->bp[page].count) /* page is still busy */
+ return;
+
+ /* page is no longer in use, it can be released */
+
+ if (bitmap->bp[page].hijacked) { /* page was hijacked, undo this now */
+ bitmap->bp[page].hijacked = 0;
+ bitmap->bp[page].map = NULL;
+ } else {
+ /* normal case, free the page */
+ ptr = bitmap->bp[page].map;
+ bitmap->bp[page].map = NULL;
+ bitmap->missing_pages++;
+ kfree(ptr);
+ }
+}
+
+/*
+ * bitmap file handling - read and write the bitmap file and its superblock
+ */
+
+/*
+ * basic page I/O operations
+ */
+
+/* IO operations when bitmap is stored near all superblocks */
+static int read_sb_page(struct mddev *mddev, loff_t offset,
+ struct page *page,
+ unsigned long index, int size)
+{
+ /* choose a good rdev and read the page from there */
+
+ struct md_rdev *rdev;
+ sector_t target;
+
+ rdev_for_each(rdev, mddev) {
+ if (! test_bit(In_sync, &rdev->flags)
+ || test_bit(Faulty, &rdev->flags)
+ || test_bit(Bitmap_sync, &rdev->flags))
+ continue;
+
+ target = offset + index * (PAGE_SIZE/512);
+
+ if (sync_page_io(rdev, target,
+ roundup(size, bdev_logical_block_size(rdev->bdev)),
+ page, REQ_OP_READ, 0, true)) {
+ page->index = index;
+ return 0;
+ }
+ }
+ return -EIO;
+}
+
+static struct md_rdev *next_active_rdev(struct md_rdev *rdev, struct mddev *mddev)
+{
+ /* Iterate the disks of an mddev, using rcu to protect access to the
+ * linked list, and raising the refcount of devices we return to ensure
+ * they don't disappear while in use.
+ * As devices are only added or removed when raid_disk is < 0 and
+ * nr_pending is 0 and In_sync is clear, the entries we return will
+ * still be in the same position on the list when we re-enter
+ * list_for_each_entry_continue_rcu.
+ *
+ * Note that if entered with 'rdev == NULL' to start at the
+ * beginning, we temporarily assign 'rdev' to an address which
+ * isn't really an rdev, but which can be used by
+ * list_for_each_entry_continue_rcu() to find the first entry.
+ */
+ rcu_read_lock();
+ if (rdev == NULL)
+ /* start at the beginning */
+ rdev = list_entry(&mddev->disks, struct md_rdev, same_set);
+ else {
+ /* release the previous rdev and start from there. */
+ rdev_dec_pending(rdev, mddev);
+ }
+ list_for_each_entry_continue_rcu(rdev, &mddev->disks, same_set) {
+ if (rdev->raid_disk >= 0 &&
+ !test_bit(Faulty, &rdev->flags)) {
+ /* this is a usable devices */
+ atomic_inc(&rdev->nr_pending);
+ rcu_read_unlock();
+ return rdev;
+ }
+ }
+ rcu_read_unlock();
+ return NULL;
+}
+
+static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
+{
+ struct md_rdev *rdev;
+ struct block_device *bdev;
+ struct mddev *mddev = bitmap->mddev;
+ struct bitmap_storage *store = &bitmap->storage;
+
+restart:
+ rdev = NULL;
+ while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
+ int size = PAGE_SIZE;
+ loff_t offset = mddev->bitmap_info.offset;
+
+ bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
+
+ if (page->index == store->file_pages-1) {
+ int last_page_size = store->bytes & (PAGE_SIZE-1);
+ if (last_page_size == 0)
+ last_page_size = PAGE_SIZE;
+ size = roundup(last_page_size,
+ bdev_logical_block_size(bdev));
+ }
+ /* Just make sure we aren't corrupting data or
+ * metadata
+ */
+ if (mddev->external) {
+ /* Bitmap could be anywhere. */
+ if (rdev->sb_start + offset + (page->index
+ * (PAGE_SIZE/512))
+ > rdev->data_offset
+ &&
+ rdev->sb_start + offset
+ < (rdev->data_offset + mddev->dev_sectors
+ + (PAGE_SIZE/512)))
+ goto bad_alignment;
+ } else if (offset < 0) {
+ /* DATA BITMAP METADATA */
+ if (offset
+ + (long)(page->index * (PAGE_SIZE/512))
+ + size/512 > 0)
+ /* bitmap runs in to metadata */
+ goto bad_alignment;
+ if (rdev->data_offset + mddev->dev_sectors
+ > rdev->sb_start + offset)
+ /* data runs in to bitmap */
+ goto bad_alignment;
+ } else if (rdev->sb_start < rdev->data_offset) {
+ /* METADATA BITMAP DATA */
+ if (rdev->sb_start
+ + offset
+ + page->index*(PAGE_SIZE/512) + size/512
+ > rdev->data_offset)
+ /* bitmap runs in to data */
+ goto bad_alignment;
+ } else {
+ /* DATA METADATA BITMAP - no problems */
+ }
+ md_super_write(mddev, rdev,
+ rdev->sb_start + offset
+ + page->index * (PAGE_SIZE/512),
+ size,
+ page);
+ }
+
+ if (wait && md_super_wait(mddev) < 0)
+ goto restart;
+ return 0;
+
+ bad_alignment:
+ return -EINVAL;
+}
+
+static void bitmap_file_kick(struct bitmap *bitmap);
+/*
+ * write out a page to a file
+ */
+static void write_page(struct bitmap *bitmap, struct page *page, int wait)
+{
+ struct buffer_head *bh;
+
+ if (bitmap->storage.file == NULL) {
+ switch (write_sb_page(bitmap, page, wait)) {
+ case -EINVAL:
+ set_bit(BITMAP_WRITE_ERROR, &bitmap->flags);
+ }
+ } else {
+
+ bh = page_buffers(page);
+
+ while (bh && bh->b_blocknr) {
+ atomic_inc(&bitmap->pending_writes);
+ set_buffer_locked(bh);
+ set_buffer_mapped(bh);
+ submit_bh(REQ_OP_WRITE, REQ_SYNC, bh);
+ bh = bh->b_this_page;
+ }
+
+ if (wait)
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
+ }
+ if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
+ bitmap_file_kick(bitmap);
+}
+
+static void end_bitmap_write(struct buffer_head *bh, int uptodate)
+{
+ struct bitmap *bitmap = bh->b_private;
+
+ if (!uptodate)
+ set_bit(BITMAP_WRITE_ERROR, &bitmap->flags);
+ if (atomic_dec_and_test(&bitmap->pending_writes))
+ wake_up(&bitmap->write_wait);
+}
+
+/* copied from buffer.c */
+static void
+__clear_page_buffers(struct page *page)
+{
+ ClearPagePrivate(page);
+ set_page_private(page, 0);
+ put_page(page);
+}
+static void free_buffers(struct page *page)
+{
+ struct buffer_head *bh;
+
+ if (!PagePrivate(page))
+ return;
+
+ bh = page_buffers(page);
+ while (bh) {
+ struct buffer_head *next = bh->b_this_page;
+ free_buffer_head(bh);
+ bh = next;
+ }
+ __clear_page_buffers(page);
+ put_page(page);
+}
+
+/* read a page from a file.
+ * We both read the page, and attach buffers to the page to record the
+ * address of each block (using bmap). These addresses will be used
+ * to write the block later, completely bypassing the filesystem.
+ * This usage is similar to how swap files are handled, and allows us
+ * to write to a file with no concerns of memory allocation failing.
+ */
+static int read_page(struct file *file, unsigned long index,
+ struct bitmap *bitmap,
+ unsigned long count,
+ struct page *page)
+{
+ int ret = 0;
+ struct inode *inode = file_inode(file);
+ struct buffer_head *bh;
+ sector_t block;
+
+ pr_debug("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE,
+ (unsigned long long)index << PAGE_SHIFT);
+
+ bh = alloc_page_buffers(page, 1<<inode->i_blkbits, 0);
+ if (!bh) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ attach_page_buffers(page, bh);
+ block = index << (PAGE_SHIFT - inode->i_blkbits);
+ while (bh) {
+ if (count == 0)
+ bh->b_blocknr = 0;
+ else {
+ bh->b_blocknr = bmap(inode, block);
+ if (bh->b_blocknr == 0) {
+ /* Cannot use this file! */
+ ret = -EINVAL;
+ goto out;
+ }
+ bh->b_bdev = inode->i_sb->s_bdev;
+ if (count < (1<<inode->i_blkbits))
+ count = 0;
+ else
+ count -= (1<<inode->i_blkbits);
+
+ bh->b_end_io = end_bitmap_write;
+ bh->b_private = bitmap;
+ atomic_inc(&bitmap->pending_writes);
+ set_buffer_locked(bh);
+ set_buffer_mapped(bh);
+ submit_bh(REQ_OP_READ, 0, bh);
+ }
+ block++;
+ bh = bh->b_this_page;
+ }
+ page->index = index;
+
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
+ if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
+ ret = -EIO;
+out:
+ if (ret)
+ pr_err("md: bitmap read error: (%dB @ %llu): %d\n",
+ (int)PAGE_SIZE,
+ (unsigned long long)index << PAGE_SHIFT,
+ ret);
+ return ret;
+}
+
+/*
+ * bitmap file superblock operations
+ */
+
+/*
+ * bitmap_wait_writes() should be called before writing any bitmap
+ * blocks, to ensure previous writes, particularly from
+ * bitmap_daemon_work(), have completed.
+ */
+static void bitmap_wait_writes(struct bitmap *bitmap)
+{
+ if (bitmap->storage.file)
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
+ else
+ /* Note that we ignore the return value. The writes
+ * might have failed, but that would just mean that
+ * some bits which should be cleared haven't been,
+ * which is safe. The relevant bitmap blocks will
+ * probably get written again, but there is no great
+ * loss if they aren't.
+ */
+ md_super_wait(bitmap->mddev);
+}
+
+
+/* update the event counter and sync the superblock to disk */
+void bitmap_update_sb(struct bitmap *bitmap)
+{
+ bitmap_super_t *sb;
+
+ if (!bitmap || !bitmap->mddev) /* no bitmap for this array */
+ return;
+ if (bitmap->mddev->bitmap_info.external)
+ return;
+ if (!bitmap->storage.sb_page) /* no superblock */
+ return;
+ sb = kmap_atomic(bitmap->storage.sb_page);
+ sb->events = cpu_to_le64(bitmap->mddev->events);
+ if (bitmap->mddev->events < bitmap->events_cleared)
+ /* rocking back to read-only */
+ bitmap->events_cleared = bitmap->mddev->events;
+ sb->events_cleared = cpu_to_le64(bitmap->events_cleared);
+ sb->state = cpu_to_le32(bitmap->flags);
+ /* Just in case these have been changed via sysfs: */
+ sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ);
+ sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind);
+ /* This might have been changed by a reshape */
+ sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
+ sb->chunksize = cpu_to_le32(bitmap->mddev->bitmap_info.chunksize);
+ sb->nodes = cpu_to_le32(bitmap->mddev->bitmap_info.nodes);
+ sb->sectors_reserved = cpu_to_le32(bitmap->mddev->
+ bitmap_info.space);
+ kunmap_atomic(sb);
+ write_page(bitmap, bitmap->storage.sb_page, 1);
+}
+EXPORT_SYMBOL(bitmap_update_sb);
+
+/* print out the bitmap file superblock */
+void bitmap_print_sb(struct bitmap *bitmap)
+{
+ bitmap_super_t *sb;
+
+ if (!bitmap || !bitmap->storage.sb_page)
+ return;
+ sb = kmap_atomic(bitmap->storage.sb_page);
+ pr_debug("%s: bitmap file superblock:\n", bmname(bitmap));
+ pr_debug(" magic: %08x\n", le32_to_cpu(sb->magic));
+ pr_debug(" version: %d\n", le32_to_cpu(sb->version));
+ pr_debug(" uuid: %08x.%08x.%08x.%08x\n",
+ le32_to_cpu(*(__u32 *)(sb->uuid+0)),
+ le32_to_cpu(*(__u32 *)(sb->uuid+4)),
+ le32_to_cpu(*(__u32 *)(sb->uuid+8)),
+ le32_to_cpu(*(__u32 *)(sb->uuid+12)));
+ pr_debug(" events: %llu\n",
+ (unsigned long long) le64_to_cpu(sb->events));
+ pr_debug("events cleared: %llu\n",
+ (unsigned long long) le64_to_cpu(sb->events_cleared));
+ pr_debug(" state: %08x\n", le32_to_cpu(sb->state));
+ pr_debug(" chunksize: %d B\n", le32_to_cpu(sb->chunksize));
+ pr_debug(" daemon sleep: %ds\n", le32_to_cpu(sb->daemon_sleep));
+ pr_debug(" sync size: %llu KB\n",
+ (unsigned long long)le64_to_cpu(sb->sync_size)/2);
+ pr_debug("max write behind: %d\n", le32_to_cpu(sb->write_behind));
+ kunmap_atomic(sb);
+}
+
+/*
+ * bitmap_new_disk_sb
+ * @bitmap
+ *
+ * This function is somewhat the reverse of bitmap_read_sb. bitmap_read_sb
+ * reads and verifies the on-disk bitmap superblock and populates bitmap_info.
+ * This function verifies 'bitmap_info' and populates the on-disk bitmap
+ * structure, which is to be written to disk.
+ *
+ * Returns: 0 on success, -Exxx on error
+ */
+static int bitmap_new_disk_sb(struct bitmap *bitmap)
+{
+ bitmap_super_t *sb;
+ unsigned long chunksize, daemon_sleep, write_behind;
+
+ bitmap->storage.sb_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (bitmap->storage.sb_page == NULL)
+ return -ENOMEM;
+ bitmap->storage.sb_page->index = 0;
+
+ sb = kmap_atomic(bitmap->storage.sb_page);
+
+ sb->magic = cpu_to_le32(BITMAP_MAGIC);
+ sb->version = cpu_to_le32(BITMAP_MAJOR_HI);
+
+ chunksize = bitmap->mddev->bitmap_info.chunksize;
+ BUG_ON(!chunksize);
+ if (!is_power_of_2(chunksize)) {
+ kunmap_atomic(sb);
+ pr_warn("bitmap chunksize not a power of 2\n");
+ return -EINVAL;
+ }
+ sb->chunksize = cpu_to_le32(chunksize);
+
+ daemon_sleep = bitmap->mddev->bitmap_info.daemon_sleep;
+ if (!daemon_sleep || (daemon_sleep > MAX_SCHEDULE_TIMEOUT)) {
+ pr_debug("Choosing daemon_sleep default (5 sec)\n");
+ daemon_sleep = 5 * HZ;
+ }
+ sb->daemon_sleep = cpu_to_le32(daemon_sleep);
+ bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
+
+ /*
+ * FIXME: write_behind for RAID1. If not specified, what
+ * is a good choice? We choose COUNTER_MAX / 2 arbitrarily.
+ */
+ write_behind = bitmap->mddev->bitmap_info.max_write_behind;
+ if (write_behind > COUNTER_MAX)
+ write_behind = COUNTER_MAX / 2;
+ sb->write_behind = cpu_to_le32(write_behind);
+ bitmap->mddev->bitmap_info.max_write_behind = write_behind;
+
+ /* keep the array size field of the bitmap superblock up to date */
+ sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
+
+ memcpy(sb->uuid, bitmap->mddev->uuid, 16);
+
+ set_bit(BITMAP_STALE, &bitmap->flags);
+ sb->state = cpu_to_le32(bitmap->flags);
+ bitmap->events_cleared = bitmap->mddev->events;
+ sb->events_cleared = cpu_to_le64(bitmap->mddev->events);
+ bitmap->mddev->bitmap_info.nodes = 0;
+
+ kunmap_atomic(sb);
+
+ return 0;
+}
+
+/* read the superblock from the bitmap file and initialize some bitmap fields */
+static int bitmap_read_sb(struct bitmap *bitmap)
+{
+ char *reason = NULL;
+ bitmap_super_t *sb;
+ unsigned long chunksize, daemon_sleep, write_behind;
+ unsigned long long events;
+ int nodes = 0;
+ unsigned long sectors_reserved = 0;
+ int err = -EINVAL;
+ struct page *sb_page;
+ loff_t offset = bitmap->mddev->bitmap_info.offset;
+
+ if (!bitmap->storage.file && !bitmap->mddev->bitmap_info.offset) {
+ chunksize = 128 * 1024 * 1024;
+ daemon_sleep = 5 * HZ;
+ write_behind = 0;
+ set_bit(BITMAP_STALE, &bitmap->flags);
+ err = 0;
+ goto out_no_sb;
+ }
+ /* page 0 is the superblock, read it... */
+ sb_page = alloc_page(GFP_KERNEL);
+ if (!sb_page)
+ return -ENOMEM;
+ bitmap->storage.sb_page = sb_page;
+
+re_read:
+ /* If cluster_slot is set, the cluster is setup */
+ if (bitmap->cluster_slot >= 0) {
+ sector_t bm_blocks = bitmap->mddev->resync_max_sectors;
+
+ sector_div(bm_blocks,
+ bitmap->mddev->bitmap_info.chunksize >> 9);
+ /* bits to bytes */
+ bm_blocks = ((bm_blocks+7) >> 3) + sizeof(bitmap_super_t);
+ /* to 4k blocks */
+ bm_blocks = DIV_ROUND_UP_SECTOR_T(bm_blocks, 4096);
+ offset = bitmap->mddev->bitmap_info.offset + (bitmap->cluster_slot * (bm_blocks << 3));
+ pr_debug("%s:%d bm slot: %d offset: %llu\n", __func__, __LINE__,
+ bitmap->cluster_slot, offset);
+ }
+
+ if (bitmap->storage.file) {
+ loff_t isize = i_size_read(bitmap->storage.file->f_mapping->host);
+ int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize;
+
+ err = read_page(bitmap->storage.file, 0,
+ bitmap, bytes, sb_page);
+ } else {
+ err = read_sb_page(bitmap->mddev,
+ offset,
+ sb_page,
+ 0, sizeof(bitmap_super_t));
+ }
+ if (err)
+ return err;
+
+ err = -EINVAL;
+ sb = kmap_atomic(sb_page);
+
+ chunksize = le32_to_cpu(sb->chunksize);
+ daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
+ write_behind = le32_to_cpu(sb->write_behind);
+ sectors_reserved = le32_to_cpu(sb->sectors_reserved);
+ /* Setup nodes/clustername only if bitmap version is
+ * cluster-compatible
+ */
+ if (sb->version == cpu_to_le32(BITMAP_MAJOR_CLUSTERED)) {
+ nodes = le32_to_cpu(sb->nodes);
+ strlcpy(bitmap->mddev->bitmap_info.cluster_name,
+ sb->cluster_name, 64);
+ }
+
+ /* verify that the bitmap-specific fields are valid */
+ if (sb->magic != cpu_to_le32(BITMAP_MAGIC))
+ reason = "bad magic";
+ else if (le32_to_cpu(sb->version) < BITMAP_MAJOR_LO ||
+ le32_to_cpu(sb->version) > BITMAP_MAJOR_CLUSTERED)
+ reason = "unrecognized superblock version";
+ else if (chunksize < 512)
+ reason = "bitmap chunksize too small";
+ else if (!is_power_of_2(chunksize))
+ reason = "bitmap chunksize not a power of 2";
+ else if (daemon_sleep < 1 || daemon_sleep > MAX_SCHEDULE_TIMEOUT)
+ reason = "daemon sleep period out of range";
+ else if (write_behind > COUNTER_MAX)
+ reason = "write-behind limit out of range (0 - 16383)";
+ if (reason) {
+ pr_warn("%s: invalid bitmap file superblock: %s\n",
+ bmname(bitmap), reason);
+ goto out;
+ }
+
+ /* keep the array size field of the bitmap superblock up to date */
+ sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
+
+ if (bitmap->mddev->persistent) {
+ /*
+ * We have a persistent array superblock, so compare the
+ * bitmap's UUID and event counter to the mddev's
+ */
+ if (memcmp(sb->uuid, bitmap->mddev->uuid, 16)) {
+ pr_warn("%s: bitmap superblock UUID mismatch\n",
+ bmname(bitmap));
+ goto out;
+ }
+ events = le64_to_cpu(sb->events);
+ if (!nodes && (events < bitmap->mddev->events)) {
+ pr_warn("%s: bitmap file is out of date (%llu < %llu) -- forcing full recovery\n",
+ bmname(bitmap), events,
+ (unsigned long long) bitmap->mddev->events);
+ set_bit(BITMAP_STALE, &bitmap->flags);
+ }
+ }
+
+ /* assign fields using values from superblock */
+ bitmap->flags |= le32_to_cpu(sb->state);
+ if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN)
+ set_bit(BITMAP_HOSTENDIAN, &bitmap->flags);
+ bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
+ strlcpy(bitmap->mddev->bitmap_info.cluster_name, sb->cluster_name, 64);
+ err = 0;
+
+out:
+ kunmap_atomic(sb);
+ /* Assigning chunksize is required for "re_read" */
+ bitmap->mddev->bitmap_info.chunksize = chunksize;
+ if (err == 0 && nodes && (bitmap->cluster_slot < 0)) {
+ err = md_setup_cluster(bitmap->mddev, nodes);
+ if (err) {
+ pr_warn("%s: Could not setup cluster service (%d)\n",
+ bmname(bitmap), err);
+ goto out_no_sb;
+ }
+ bitmap->cluster_slot = md_cluster_ops->slot_number(bitmap->mddev);
+ goto re_read;
+ }
+
+
+out_no_sb:
+ if (test_bit(BITMAP_STALE, &bitmap->flags))
+ bitmap->events_cleared = bitmap->mddev->events;
+ bitmap->mddev->bitmap_info.chunksize = chunksize;
+ bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
+ bitmap->mddev->bitmap_info.max_write_behind = write_behind;
+ bitmap->mddev->bitmap_info.nodes = nodes;
+ if (bitmap->mddev->bitmap_info.space == 0 ||
+ bitmap->mddev->bitmap_info.space > sectors_reserved)
+ bitmap->mddev->bitmap_info.space = sectors_reserved;
+ if (err) {
+ bitmap_print_sb(bitmap);
+ if (bitmap->cluster_slot < 0)
+ md_cluster_stop(bitmap->mddev);
+ }
+ return err;
+}
+
+/*
+ * general bitmap file operations
+ */
+
+/*
+ * on-disk bitmap:
+ *
+ * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
+ * file a page at a time. There's a superblock at the start of the file.
+ */
+/* calculate the index of the page that contains this bit */
+static inline unsigned long file_page_index(struct bitmap_storage *store,
+ unsigned long chunk)
+{
+ if (store->sb_page)
+ chunk += sizeof(bitmap_super_t) << 3;
+ return chunk >> PAGE_BIT_SHIFT;
+}
+
+/* calculate the (bit) offset of this bit within a page */
+static inline unsigned long file_page_offset(struct bitmap_storage *store,
+ unsigned long chunk)
+{
+ if (store->sb_page)
+ chunk += sizeof(bitmap_super_t) << 3;
+ return chunk & (PAGE_BITS - 1);
+}
+
+/*
+ * return a pointer to the page in the filemap that contains the given bit
+ *
+ */
+static inline struct page *filemap_get_page(struct bitmap_storage *store,
+ unsigned long chunk)
+{
+ if (file_page_index(store, chunk) >= store->file_pages)
+ return NULL;
+ return store->filemap[file_page_index(store, chunk)];
+}
+
+static int bitmap_storage_alloc(struct bitmap_storage *store,
+ unsigned long chunks, int with_super,
+ int slot_number)
+{
+ int pnum, offset = 0;
+ unsigned long num_pages;
+ unsigned long bytes;
+
+ bytes = DIV_ROUND_UP(chunks, 8);
+ if (with_super)
+ bytes += sizeof(bitmap_super_t);
+
+ num_pages = DIV_ROUND_UP(bytes, PAGE_SIZE);
+ offset = slot_number * num_pages;
+
+ store->filemap = kmalloc(sizeof(struct page *)
+ * num_pages, GFP_KERNEL);
+ if (!store->filemap)
+ return -ENOMEM;
+
+ if (with_super && !store->sb_page) {
+ store->sb_page = alloc_page(GFP_KERNEL|__GFP_ZERO);
+ if (store->sb_page == NULL)
+ return -ENOMEM;
+ }
+
+ pnum = 0;
+ if (store->sb_page) {
+ store->filemap[0] = store->sb_page;
+ pnum = 1;
+ store->sb_page->index = offset;
+ }
+
+ for ( ; pnum < num_pages; pnum++) {
+ store->filemap[pnum] = alloc_page(GFP_KERNEL|__GFP_ZERO);
+ if (!store->filemap[pnum]) {
+ store->file_pages = pnum;
+ return -ENOMEM;
+ }
+ store->filemap[pnum]->index = pnum + offset;
+ }
+ store->file_pages = pnum;
+
+ /* We need 4 bits per page, rounded up to a multiple
+ * of sizeof(unsigned long) */
+ store->filemap_attr = kzalloc(
+ roundup(DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
+ GFP_KERNEL);
+ if (!store->filemap_attr)
+ return -ENOMEM;
+
+ store->bytes = bytes;
+
+ return 0;
+}
+
+static void bitmap_file_unmap(struct bitmap_storage *store)
+{
+ struct page **map, *sb_page;
+ int pages;
+ struct file *file;
+
+ file = store->file;
+ map = store->filemap;
+ pages = store->file_pages;
+ sb_page = store->sb_page;
+
+ while (pages--)
+ if (map[pages] != sb_page) /* 0 is sb_page, release it below */
+ free_buffers(map[pages]);
+ kfree(map);
+ kfree(store->filemap_attr);
+
+ if (sb_page)
+ free_buffers(sb_page);
+
+ if (file) {
+ struct inode *inode = file_inode(file);
+ invalidate_mapping_pages(inode->i_mapping, 0, -1);
+ fput(file);
+ }
+}
+
+/*
+ * bitmap_file_kick - if an error occurs while manipulating the bitmap file
+ * then it is no longer reliable, so we stop using it and we mark the file
+ * as failed in the superblock
+ */
+static void bitmap_file_kick(struct bitmap *bitmap)
+{
+ char *path, *ptr = NULL;
+
+ if (!test_and_set_bit(BITMAP_STALE, &bitmap->flags)) {
+ bitmap_update_sb(bitmap);
+
+ if (bitmap->storage.file) {
+ path = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (path)
+ ptr = file_path(bitmap->storage.file,
+ path, PAGE_SIZE);
+
+ pr_warn("%s: kicking failed bitmap file %s from array!\n",
+ bmname(bitmap), IS_ERR(ptr) ? "" : ptr);
+
+ kfree(path);
+ } else
+ pr_warn("%s: disabling internal bitmap due to errors\n",
+ bmname(bitmap));
+ }
+}
+
+enum bitmap_page_attr {
+ BITMAP_PAGE_DIRTY = 0, /* there are set bits that need to be synced */
+ BITMAP_PAGE_PENDING = 1, /* there are bits that are being cleaned.
+ * i.e. counter is 1 or 2. */
+ BITMAP_PAGE_NEEDWRITE = 2, /* there are cleared bits that need to be synced */
+};
+
+static inline void set_page_attr(struct bitmap *bitmap, int pnum,
+ enum bitmap_page_attr attr)
+{
+ set_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
+}
+
+static inline void clear_page_attr(struct bitmap *bitmap, int pnum,
+ enum bitmap_page_attr attr)
+{
+ clear_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
+}
+
+static inline int test_page_attr(struct bitmap *bitmap, int pnum,
+ enum bitmap_page_attr attr)
+{
+ return test_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
+}
+
+static inline int test_and_clear_page_attr(struct bitmap *bitmap, int pnum,
+ enum bitmap_page_attr attr)
+{
+ return test_and_clear_bit((pnum<<2) + attr,
+ bitmap->storage.filemap_attr);
+}
+/*
+ * bitmap_file_set_bit -- called before performing a write to the md device
+ * to set (and eventually sync) a particular bit in the bitmap file
+ *
+ * we set the bit immediately, then we record the page number so that
+ * when an unplug occurs, we can flush the dirty pages out to disk
+ */
+static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
+{
+ unsigned long bit;
+ struct page *page;
+ void *kaddr;
+ unsigned long chunk = block >> bitmap->counts.chunkshift;
+ struct bitmap_storage *store = &bitmap->storage;
+ unsigned long node_offset = 0;
+
+ if (mddev_is_clustered(bitmap->mddev))
+ node_offset = bitmap->cluster_slot * store->file_pages;
+
+ page = filemap_get_page(&bitmap->storage, chunk);
+ if (!page)
+ return;
+ bit = file_page_offset(&bitmap->storage, chunk);
+
+ /* set the bit */
+ kaddr = kmap_atomic(page);
+ if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
+ set_bit(bit, kaddr);
+ else
+ set_bit_le(bit, kaddr);
+ kunmap_atomic(kaddr);
+ pr_debug("set file bit %lu page %lu\n", bit, page->index);
+ /* record page number so it gets flushed to disk when unplug occurs */
+ set_page_attr(bitmap, page->index - node_offset, BITMAP_PAGE_DIRTY);
+}
+
+static void bitmap_file_clear_bit(struct bitmap *bitmap, sector_t block)
+{
+ unsigned long bit;
+ struct page *page;
+ void *paddr;
+ unsigned long chunk = block >> bitmap->counts.chunkshift;
+ struct bitmap_storage *store = &bitmap->storage;
+ unsigned long node_offset = 0;
+
+ if (mddev_is_clustered(bitmap->mddev))
+ node_offset = bitmap->cluster_slot * store->file_pages;
+
+ page = filemap_get_page(&bitmap->storage, chunk);
+ if (!page)
+ return;
+ bit = file_page_offset(&bitmap->storage, chunk);
+ paddr = kmap_atomic(page);
+ if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
+ clear_bit(bit, paddr);
+ else
+ clear_bit_le(bit, paddr);
+ kunmap_atomic(paddr);
+ if (!test_page_attr(bitmap, page->index - node_offset, BITMAP_PAGE_NEEDWRITE)) {
+ set_page_attr(bitmap, page->index - node_offset, BITMAP_PAGE_PENDING);
+ bitmap->allclean = 0;
+ }
+}
+
+static int bitmap_file_test_bit(struct bitmap *bitmap, sector_t block)
+{
+ unsigned long bit;
+ struct page *page;
+ void *paddr;
+ unsigned long chunk = block >> bitmap->counts.chunkshift;
+ int set = 0;
+
+ page = filemap_get_page(&bitmap->storage, chunk);
+ if (!page)
+ return -EINVAL;
+ bit = file_page_offset(&bitmap->storage, chunk);
+ paddr = kmap_atomic(page);
+ if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
+ set = test_bit(bit, paddr);
+ else
+ set = test_bit_le(bit, paddr);
+ kunmap_atomic(paddr);
+ return set;
+}
+
+
+/* this gets called when the md device is ready to unplug its underlying
+ * (slave) device queues -- before we let any writes go down, we need to
+ * sync the dirty pages of the bitmap file to disk */
+void bitmap_unplug(struct bitmap *bitmap)
+{
+ unsigned long i;
+ int dirty, need_write;
+ int writing = 0;
+
+ if (!bitmap || !bitmap->storage.filemap ||
+ test_bit(BITMAP_STALE, &bitmap->flags))
+ return;
+
+ /* look at each page to see if there are any set bits that need to be
+ * flushed out to disk */
+ for (i = 0; i < bitmap->storage.file_pages; i++) {
+ if (!bitmap->storage.filemap)
+ return;
+ dirty = test_and_clear_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
+ need_write = test_and_clear_page_attr(bitmap, i,
+ BITMAP_PAGE_NEEDWRITE);
+ if (dirty || need_write) {
+ if (!writing) {
+ bitmap_wait_writes(bitmap);
+ if (bitmap->mddev->queue)
+ blk_add_trace_msg(bitmap->mddev->queue,
+ "md bitmap_unplug");
+ }
+ clear_page_attr(bitmap, i, BITMAP_PAGE_PENDING);
+ write_page(bitmap, bitmap->storage.filemap[i], 0);
+ writing = 1;
+ }
+ }
+ if (writing)
+ bitmap_wait_writes(bitmap);
+
+ if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
+ bitmap_file_kick(bitmap);
+}
+EXPORT_SYMBOL(bitmap_unplug);
+
+static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
+/* * bitmap_init_from_disk -- called at bitmap_create time to initialize
+ * the in-memory bitmap from the on-disk bitmap -- also, sets up the
+ * memory mapping of the bitmap file
+ * Special cases:
+ * if there's no bitmap file, or if the bitmap file had been
+ * previously kicked from the array, we mark all the bits as
+ * 1's in order to cause a full resync.
+ *
+ * We ignore all bits for sectors that end earlier than 'start'.
+ * This is used when reading an out-of-date bitmap...
+ */
+static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
+{
+ unsigned long i, chunks, index, oldindex, bit, node_offset = 0;
+ struct page *page = NULL;
+ unsigned long bit_cnt = 0;
+ struct file *file;
+ unsigned long offset;
+ int outofdate;
+ int ret = -ENOSPC;
+ void *paddr;
+ struct bitmap_storage *store = &bitmap->storage;
+
+ chunks = bitmap->counts.chunks;
+ file = store->file;
+
+ if (!file && !bitmap->mddev->bitmap_info.offset) {
+ /* No permanent bitmap - fill with '1s'. */
+ store->filemap = NULL;
+ store->file_pages = 0;
+ for (i = 0; i < chunks ; i++) {
+ /* if the disk bit is set, set the memory bit */
+ int needed = ((sector_t)(i+1) << (bitmap->counts.chunkshift)
+ >= start);
+ bitmap_set_memory_bits(bitmap,
+ (sector_t)i << bitmap->counts.chunkshift,
+ needed);
+ }
+ return 0;
+ }
+
+ outofdate = test_bit(BITMAP_STALE, &bitmap->flags);
+ if (outofdate)
+ pr_warn("%s: bitmap file is out of date, doing full recovery\n", bmname(bitmap));
+
+ if (file && i_size_read(file->f_mapping->host) < store->bytes) {
+ pr_warn("%s: bitmap file too short %lu < %lu\n",
+ bmname(bitmap),
+ (unsigned long) i_size_read(file->f_mapping->host),
+ store->bytes);
+ goto err;
+ }
+
+ oldindex = ~0L;
+ offset = 0;
+ if (!bitmap->mddev->bitmap_info.external)
+ offset = sizeof(bitmap_super_t);
+
+ if (mddev_is_clustered(bitmap->mddev))
+ node_offset = bitmap->cluster_slot * (DIV_ROUND_UP(store->bytes, PAGE_SIZE));
+
+ for (i = 0; i < chunks; i++) {
+ int b;
+ index = file_page_index(&bitmap->storage, i);
+ bit = file_page_offset(&bitmap->storage, i);
+ if (index != oldindex) { /* this is a new page, read it in */
+ int count;
+ /* unmap the old page, we're done with it */
+ if (index == store->file_pages-1)
+ count = store->bytes - index * PAGE_SIZE;
+ else
+ count = PAGE_SIZE;
+ page = store->filemap[index];
+ if (file)
+ ret = read_page(file, index, bitmap,
+ count, page);
+ else
+ ret = read_sb_page(
+ bitmap->mddev,
+ bitmap->mddev->bitmap_info.offset,
+ page,
+ index + node_offset, count);
+
+ if (ret)
+ goto err;
+
+ oldindex = index;
+
+ if (outofdate) {
+ /*
+ * if bitmap is out of date, dirty the
+ * whole page and write it out
+ */
+ paddr = kmap_atomic(page);
+ memset(paddr + offset, 0xff,
+ PAGE_SIZE - offset);
+ kunmap_atomic(paddr);
+ write_page(bitmap, page, 1);
+
+ ret = -EIO;
+ if (test_bit(BITMAP_WRITE_ERROR,
+ &bitmap->flags))
+ goto err;
+ }
+ }
+ paddr = kmap_atomic(page);
+ if (test_bit(BITMAP_HOSTENDIAN, &bitmap->flags))
+ b = test_bit(bit, paddr);
+ else
+ b = test_bit_le(bit, paddr);
+ kunmap_atomic(paddr);
+ if (b) {
+ /* if the disk bit is set, set the memory bit */
+ int needed = ((sector_t)(i+1) << bitmap->counts.chunkshift
+ >= start);
+ bitmap_set_memory_bits(bitmap,
+ (sector_t)i << bitmap->counts.chunkshift,
+ needed);
+ bit_cnt++;
+ }
+ offset = 0;
+ }
+
+ pr_debug("%s: bitmap initialized from disk: read %lu pages, set %lu of %lu bits\n",
+ bmname(bitmap), store->file_pages,
+ bit_cnt, chunks);
+
+ return 0;
+
+ err:
+ pr_warn("%s: bitmap initialisation failed: %d\n",
+ bmname(bitmap), ret);
+ return ret;
+}
+
+void bitmap_write_all(struct bitmap *bitmap)
+{
+ /* We don't actually write all bitmap blocks here,
+ * just flag them as needing to be written
+ */
+ int i;
+
+ if (!bitmap || !bitmap->storage.filemap)
+ return;
+ if (bitmap->storage.file)
+ /* Only one copy, so nothing needed */
+ return;
+
+ for (i = 0; i < bitmap->storage.file_pages; i++)
+ set_page_attr(bitmap, i,
+ BITMAP_PAGE_NEEDWRITE);
+ bitmap->allclean = 0;
+}
+
+static void bitmap_count_page(struct bitmap_counts *bitmap,
+ sector_t offset, int inc)
+{
+ sector_t chunk = offset >> bitmap->chunkshift;
+ unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
+ bitmap->bp[page].count += inc;
+ bitmap_checkfree(bitmap, page);
+}
+
+static void bitmap_set_pending(struct bitmap_counts *bitmap, sector_t offset)
+{
+ sector_t chunk = offset >> bitmap->chunkshift;
+ unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
+ struct bitmap_page *bp = &bitmap->bp[page];
+
+ if (!bp->pending)
+ bp->pending = 1;
+}
+
+static bitmap_counter_t *bitmap_get_counter(struct bitmap_counts *bitmap,
+ sector_t offset, sector_t *blocks,
+ int create);
+
+/*
+ * bitmap daemon -- periodically wakes up to clean bits and flush pages
+ * out to disk
+ */
+
+void bitmap_daemon_work(struct mddev *mddev)
+{
+ struct bitmap *bitmap;
+ unsigned long j;
+ unsigned long nextpage;
+ sector_t blocks;
+ struct bitmap_counts *counts;
+
+ /* Use a mutex to guard daemon_work against
+ * bitmap_destroy.
+ */
+ mutex_lock(&mddev->bitmap_info.mutex);
+ bitmap = mddev->bitmap;
+ if (bitmap == NULL) {
+ mutex_unlock(&mddev->bitmap_info.mutex);
+ return;
+ }
+ if (time_before(jiffies, bitmap->daemon_lastrun
+ + mddev->bitmap_info.daemon_sleep))
+ goto done;
+
+ bitmap->daemon_lastrun = jiffies;
+ if (bitmap->allclean) {
+ mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
+ goto done;
+ }
+ bitmap->allclean = 1;
+
+ if (bitmap->mddev->queue)
+ blk_add_trace_msg(bitmap->mddev->queue,
+ "md bitmap_daemon_work");
+
+ /* Any file-page which is PENDING now needs to be written.
+ * So set NEEDWRITE now, then after we make any last-minute changes
+ * we will write it.
+ */
+ for (j = 0; j < bitmap->storage.file_pages; j++)
+ if (test_and_clear_page_attr(bitmap, j,
+ BITMAP_PAGE_PENDING))
+ set_page_attr(bitmap, j,
+ BITMAP_PAGE_NEEDWRITE);
+
+ if (bitmap->need_sync &&
+ mddev->bitmap_info.external == 0) {
+ /* Arrange for superblock update as well as
+ * other changes */
+ bitmap_super_t *sb;
+ bitmap->need_sync = 0;
+ if (bitmap->storage.filemap) {
+ sb = kmap_atomic(bitmap->storage.sb_page);
+ sb->events_cleared =
+ cpu_to_le64(bitmap->events_cleared);
+ kunmap_atomic(sb);
+ set_page_attr(bitmap, 0,
+ BITMAP_PAGE_NEEDWRITE);
+ }
+ }
+ /* Now look at the bitmap counters and if any are '2' or '1',
+ * decrement and handle accordingly.
+ */
+ counts = &bitmap->counts;
+ spin_lock_irq(&counts->lock);
+ nextpage = 0;
+ for (j = 0; j < counts->chunks; j++) {
+ bitmap_counter_t *bmc;
+ sector_t block = (sector_t)j << counts->chunkshift;
+
+ if (j == nextpage) {
+ nextpage += PAGE_COUNTER_RATIO;
+ if (!counts->bp[j >> PAGE_COUNTER_SHIFT].pending) {
+ j |= PAGE_COUNTER_MASK;
+ continue;
+ }
+ counts->bp[j >> PAGE_COUNTER_SHIFT].pending = 0;
+ }
+ bmc = bitmap_get_counter(counts,
+ block,
+ &blocks, 0);
+
+ if (!bmc) {
+ j |= PAGE_COUNTER_MASK;
+ continue;
+ }
+ if (*bmc == 1 && !bitmap->need_sync) {
+ /* We can clear the bit */
+ *bmc = 0;
+ bitmap_count_page(counts, block, -1);
+ bitmap_file_clear_bit(bitmap, block);
+ } else if (*bmc && *bmc <= 2) {
+ *bmc = 1;
+ bitmap_set_pending(counts, block);
+ bitmap->allclean = 0;
+ }
+ }
+ spin_unlock_irq(&counts->lock);
+
+ bitmap_wait_writes(bitmap);
+ /* Now start writeout on any page in NEEDWRITE that isn't DIRTY.
+ * DIRTY pages need to be written by bitmap_unplug so it can wait
+ * for them.
+ * If we find any DIRTY page we stop there and let bitmap_unplug
+ * handle all the rest. This is important in the case where
+ * the first blocking holds the superblock and it has been updated.
+ * We mustn't write any other blocks before the superblock.
+ */
+ for (j = 0;
+ j < bitmap->storage.file_pages
+ && !test_bit(BITMAP_STALE, &bitmap->flags);
+ j++) {
+ if (test_page_attr(bitmap, j,
+ BITMAP_PAGE_DIRTY))
+ /* bitmap_unplug will handle the rest */
+ break;
+ if (test_and_clear_page_attr(bitmap, j,
+ BITMAP_PAGE_NEEDWRITE)) {
+ write_page(bitmap, bitmap->storage.filemap[j], 0);
+ }
+ }
+
+ done:
+ if (bitmap->allclean == 0)
+ mddev->thread->timeout =
+ mddev->bitmap_info.daemon_sleep;
+ mutex_unlock(&mddev->bitmap_info.mutex);
+}
+
+static bitmap_counter_t *bitmap_get_counter(struct bitmap_counts *bitmap,
+ sector_t offset, sector_t *blocks,
+ int create)
+__releases(bitmap->lock)
+__acquires(bitmap->lock)
+{
+ /* If 'create', we might release the lock and reclaim it.
+ * The lock must have been taken with interrupts enabled.
+ * If !create, we don't release the lock.
+ */
+ sector_t chunk = offset >> bitmap->chunkshift;
+ unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
+ unsigned long pageoff = (chunk & PAGE_COUNTER_MASK) << COUNTER_BYTE_SHIFT;
+ sector_t csize;
+ int err;
+
+ err = bitmap_checkpage(bitmap, page, create, 0);
+
+ if (bitmap->bp[page].hijacked ||
+ bitmap->bp[page].map == NULL)
+ csize = ((sector_t)1) << (bitmap->chunkshift +
+ PAGE_COUNTER_SHIFT - 1);
+ else
+ csize = ((sector_t)1) << bitmap->chunkshift;
+ *blocks = csize - (offset & (csize - 1));
+
+ if (err < 0)
+ return NULL;
+
+ /* now locked ... */
+
+ if (bitmap->bp[page].hijacked) { /* hijacked pointer */
+ /* should we use the first or second counter field
+ * of the hijacked pointer? */
+ int hi = (pageoff > PAGE_COUNTER_MASK);
+ return &((bitmap_counter_t *)
+ &bitmap->bp[page].map)[hi];
+ } else /* page is allocated */
+ return (bitmap_counter_t *)
+ &(bitmap->bp[page].map[pageoff]);
+}
+
+int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind)
+{
+ if (!bitmap)
+ return 0;
+
+ if (behind) {
+ int bw;
+ atomic_inc(&bitmap->behind_writes);
+ bw = atomic_read(&bitmap->behind_writes);
+ if (bw > bitmap->behind_writes_used)
+ bitmap->behind_writes_used = bw;
+
+ pr_debug("inc write-behind count %d/%lu\n",
+ bw, bitmap->mddev->bitmap_info.max_write_behind);
+ }
+
+ while (sectors) {
+ sector_t blocks;
+ bitmap_counter_t *bmc;
+
+ spin_lock_irq(&bitmap->counts.lock);
+ bmc = bitmap_get_counter(&bitmap->counts, offset, &blocks, 1);
+ if (!bmc) {
+ spin_unlock_irq(&bitmap->counts.lock);
+ return 0;
+ }
+
+ if (unlikely(COUNTER(*bmc) == COUNTER_MAX)) {
+ DEFINE_WAIT(__wait);
+ /* note that it is safe to do the prepare_to_wait
+ * after the test as long as we do it before dropping
+ * the spinlock.
+ */
+ prepare_to_wait(&bitmap->overflow_wait, &__wait,
+ TASK_UNINTERRUPTIBLE);
+ spin_unlock_irq(&bitmap->counts.lock);
+ schedule();
+ finish_wait(&bitmap->overflow_wait, &__wait);
+ continue;
+ }
+
+ switch (*bmc) {
+ case 0:
+ bitmap_file_set_bit(bitmap, offset);
+ bitmap_count_page(&bitmap->counts, offset, 1);
+ /* fall through */
+ case 1:
+ *bmc = 2;
+ }
+
+ (*bmc)++;
+
+ spin_unlock_irq(&bitmap->counts.lock);
+
+ offset += blocks;
+ if (sectors > blocks)
+ sectors -= blocks;
+ else
+ sectors = 0;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(bitmap_startwrite);
+
+void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
+ int success, int behind)
+{
+ if (!bitmap)
+ return;
+ if (behind) {
+ if (atomic_dec_and_test(&bitmap->behind_writes))
+ wake_up(&bitmap->behind_wait);
+ pr_debug("dec write-behind count %d/%lu\n",
+ atomic_read(&bitmap->behind_writes),
+ bitmap->mddev->bitmap_info.max_write_behind);
+ }
+
+ while (sectors) {
+ sector_t blocks;
+ unsigned long flags;
+ bitmap_counter_t *bmc;
+
+ spin_lock_irqsave(&bitmap->counts.lock, flags);
+ bmc = bitmap_get_counter(&bitmap->counts, offset, &blocks, 0);
+ if (!bmc) {
+ spin_unlock_irqrestore(&bitmap->counts.lock, flags);
+ return;
+ }
+
+ if (success && !bitmap->mddev->degraded &&
+ bitmap->events_cleared < bitmap->mddev->events) {
+ bitmap->events_cleared = bitmap->mddev->events;
+ bitmap->need_sync = 1;
+ sysfs_notify_dirent_safe(bitmap->sysfs_can_clear);
+ }
+
+ if (!success && !NEEDED(*bmc))
+ *bmc |= NEEDED_MASK;
+
+ if (COUNTER(*bmc) == COUNTER_MAX)
+ wake_up(&bitmap->overflow_wait);
+
+ (*bmc)--;
+ if (*bmc <= 2) {
+ bitmap_set_pending(&bitmap->counts, offset);
+ bitmap->allclean = 0;
+ }
+ spin_unlock_irqrestore(&bitmap->counts.lock, flags);
+ offset += blocks;
+ if (sectors > blocks)
+ sectors -= blocks;
+ else
+ sectors = 0;
+ }
+}
+EXPORT_SYMBOL(bitmap_endwrite);
+
+static int __bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks,
+ int degraded)
+{
+ bitmap_counter_t *bmc;
+ int rv;
+ if (bitmap == NULL) {/* FIXME or bitmap set as 'failed' */
+ *blocks = 1024;
+ return 1; /* always resync if no bitmap */
+ }
+ spin_lock_irq(&bitmap->counts.lock);
+ bmc = bitmap_get_counter(&bitmap->counts, offset, blocks, 0);
+ rv = 0;
+ if (bmc) {
+ /* locked */
+ if (RESYNC(*bmc))
+ rv = 1;
+ else if (NEEDED(*bmc)) {
+ rv = 1;
+ if (!degraded) { /* don't set/clear bits if degraded */
+ *bmc |= RESYNC_MASK;
+ *bmc &= ~NEEDED_MASK;
+ }
+ }
+ }
+ spin_unlock_irq(&bitmap->counts.lock);
+ return rv;
+}
+
+int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks,
+ int degraded)
+{
+ /* bitmap_start_sync must always report on multiples of whole
+ * pages, otherwise resync (which is very PAGE_SIZE based) will
+ * get confused.
+ * So call __bitmap_start_sync repeatedly (if needed) until
+ * At least PAGE_SIZE>>9 blocks are covered.
+ * Return the 'or' of the result.
+ */
+ int rv = 0;
+ sector_t blocks1;
+
+ *blocks = 0;
+ while (*blocks < (PAGE_SIZE>>9)) {
+ rv |= __bitmap_start_sync(bitmap, offset,
+ &blocks1, degraded);
+ offset += blocks1;
+ *blocks += blocks1;
+ }
+ return rv;
+}
+EXPORT_SYMBOL(bitmap_start_sync);
+
+void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted)
+{
+ bitmap_counter_t *bmc;
+ unsigned long flags;
+
+ if (bitmap == NULL) {
+ *blocks = 1024;
+ return;
+ }
+ spin_lock_irqsave(&bitmap->counts.lock, flags);
+ bmc = bitmap_get_counter(&bitmap->counts, offset, blocks, 0);
+ if (bmc == NULL)
+ goto unlock;
+ /* locked */
+ if (RESYNC(*bmc)) {
+ *bmc &= ~RESYNC_MASK;
+
+ if (!NEEDED(*bmc) && aborted)
+ *bmc |= NEEDED_MASK;
+ else {
+ if (*bmc <= 2) {
+ bitmap_set_pending(&bitmap->counts, offset);
+ bitmap->allclean = 0;
+ }
+ }
+ }
+ unlock:
+ spin_unlock_irqrestore(&bitmap->counts.lock, flags);
+}
+EXPORT_SYMBOL(bitmap_end_sync);
+
+void bitmap_close_sync(struct bitmap *bitmap)
+{
+ /* Sync has finished, and any bitmap chunks that weren't synced
+ * properly have been aborted. It remains to us to clear the
+ * RESYNC bit wherever it is still on
+ */
+ sector_t sector = 0;
+ sector_t blocks;
+ if (!bitmap)
+ return;
+ while (sector < bitmap->mddev->resync_max_sectors) {
+ bitmap_end_sync(bitmap, sector, &blocks, 0);
+ sector += blocks;
+ }
+}
+EXPORT_SYMBOL(bitmap_close_sync);
+
+void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector, bool force)
+{
+ sector_t s = 0;
+ sector_t blocks;
+
+ if (!bitmap)
+ return;
+ if (sector == 0) {
+ bitmap->last_end_sync = jiffies;
+ return;
+ }
+ if (!force && time_before(jiffies, (bitmap->last_end_sync
+ + bitmap->mddev->bitmap_info.daemon_sleep)))
+ return;
+ wait_event(bitmap->mddev->recovery_wait,
+ atomic_read(&bitmap->mddev->recovery_active) == 0);
+
+ bitmap->mddev->curr_resync_completed = sector;
+ set_bit(MD_SB_CHANGE_CLEAN, &bitmap->mddev->sb_flags);
+ sector &= ~((1ULL << bitmap->counts.chunkshift) - 1);
+ s = 0;
+ while (s < sector && s < bitmap->mddev->resync_max_sectors) {
+ bitmap_end_sync(bitmap, s, &blocks, 0);
+ s += blocks;
+ }
+ bitmap->last_end_sync = jiffies;
+ sysfs_notify(&bitmap->mddev->kobj, NULL, "sync_completed");
+}
+EXPORT_SYMBOL(bitmap_cond_end_sync);
+
+void bitmap_sync_with_cluster(struct mddev *mddev,
+ sector_t old_lo, sector_t old_hi,
+ sector_t new_lo, sector_t new_hi)
+{
+ struct bitmap *bitmap = mddev->bitmap;
+ sector_t sector, blocks = 0;
+
+ for (sector = old_lo; sector < new_lo; ) {
+ bitmap_end_sync(bitmap, sector, &blocks, 0);
+ sector += blocks;
+ }
+ WARN((blocks > new_lo) && old_lo, "alignment is not correct for lo\n");
+
+ for (sector = old_hi; sector < new_hi; ) {
+ bitmap_start_sync(bitmap, sector, &blocks, 0);
+ sector += blocks;
+ }
+ WARN((blocks > new_hi) && old_hi, "alignment is not correct for hi\n");
+}
+EXPORT_SYMBOL(bitmap_sync_with_cluster);
+
+static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed)
+{
+ /* For each chunk covered by any of these sectors, set the
+ * counter to 2 and possibly set resync_needed. They should all
+ * be 0 at this point
+ */
+
+ sector_t secs;
+ bitmap_counter_t *bmc;
+ spin_lock_irq(&bitmap->counts.lock);
+ bmc = bitmap_get_counter(&bitmap->counts, offset, &secs, 1);
+ if (!bmc) {
+ spin_unlock_irq(&bitmap->counts.lock);
+ return;
+ }
+ if (!*bmc) {
+ *bmc = 2;
+ bitmap_count_page(&bitmap->counts, offset, 1);
+ bitmap_set_pending(&bitmap->counts, offset);
+ bitmap->allclean = 0;
+ }
+ if (needed)
+ *bmc |= NEEDED_MASK;
+ spin_unlock_irq(&bitmap->counts.lock);
+}
+
+/* dirty the memory and file bits for bitmap chunks "s" to "e" */
+void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e)
+{
+ unsigned long chunk;
+
+ for (chunk = s; chunk <= e; chunk++) {
+ sector_t sec = (sector_t)chunk << bitmap->counts.chunkshift;
+ bitmap_set_memory_bits(bitmap, sec, 1);
+ bitmap_file_set_bit(bitmap, sec);
+ if (sec < bitmap->mddev->recovery_cp)
+ /* We are asserting that the array is dirty,
+ * so move the recovery_cp address back so
+ * that it is obvious that it is dirty
+ */
+ bitmap->mddev->recovery_cp = sec;
+ }
+}
+
+/*
+ * flush out any pending updates
+ */
+void bitmap_flush(struct mddev *mddev)
+{
+ struct bitmap *bitmap = mddev->bitmap;
+ long sleep;
+
+ if (!bitmap) /* there was no bitmap */
+ return;
+
+ /* run the daemon_work three time to ensure everything is flushed
+ * that can be
+ */
+ sleep = mddev->bitmap_info.daemon_sleep * 2;
+ bitmap->daemon_lastrun -= sleep;
+ bitmap_daemon_work(mddev);
+ bitmap->daemon_lastrun -= sleep;
+ bitmap_daemon_work(mddev);
+ bitmap->daemon_lastrun -= sleep;
+ bitmap_daemon_work(mddev);
+ bitmap_update_sb(bitmap);
+}
+
+/*
+ * free memory that was allocated
+ */
+void bitmap_free(struct bitmap *bitmap)
+{
+ unsigned long k, pages;
+ struct bitmap_page *bp;
+
+ if (!bitmap) /* there was no bitmap */
+ return;
+
+ if (bitmap->sysfs_can_clear)
+ sysfs_put(bitmap->sysfs_can_clear);
+
+ if (mddev_is_clustered(bitmap->mddev) && bitmap->mddev->cluster_info &&
+ bitmap->cluster_slot == md_cluster_ops->slot_number(bitmap->mddev))
+ md_cluster_stop(bitmap->mddev);
+
+ /* Shouldn't be needed - but just in case.... */
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes) == 0);
+
+ /* release the bitmap file */
+ bitmap_file_unmap(&bitmap->storage);
+
+ bp = bitmap->counts.bp;
+ pages = bitmap->counts.pages;
+
+ /* free all allocated memory */
+
+ if (bp) /* deallocate the page memory */
+ for (k = 0; k < pages; k++)
+ if (bp[k].map && !bp[k].hijacked)
+ kfree(bp[k].map);
+ kfree(bp);
+ kfree(bitmap);
+}
+EXPORT_SYMBOL(bitmap_free);
+
+void bitmap_wait_behind_writes(struct mddev *mddev)
+{
+ struct bitmap *bitmap = mddev->bitmap;
+
+ /* wait for behind writes to complete */
+ if (bitmap && atomic_read(&bitmap->behind_writes) > 0) {
+ pr_debug("md:%s: behind writes in progress - waiting to stop.\n",
+ mdname(mddev));
+ /* need to kick something here to make sure I/O goes? */
+ wait_event(bitmap->behind_wait,
+ atomic_read(&bitmap->behind_writes) == 0);
+ }
+}
+
+void bitmap_destroy(struct mddev *mddev)
+{
+ struct bitmap *bitmap = mddev->bitmap;
+
+ if (!bitmap) /* there was no bitmap */
+ return;
+
+ bitmap_wait_behind_writes(mddev);
+
+ mutex_lock(&mddev->bitmap_info.mutex);
+ spin_lock(&mddev->lock);
+ mddev->bitmap = NULL; /* disconnect from the md device */
+ spin_unlock(&mddev->lock);
+ mutex_unlock(&mddev->bitmap_info.mutex);
+ if (mddev->thread)
+ mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
+
+ bitmap_free(bitmap);
+}
+
+/*
+ * initialize the bitmap structure
+ * if this returns an error, bitmap_destroy must be called to do clean up
+ * once mddev->bitmap is set
+ */
+struct bitmap *bitmap_create(struct mddev *mddev, int slot)
+{
+ struct bitmap *bitmap;
+ sector_t blocks = mddev->resync_max_sectors;
+ struct file *file = mddev->bitmap_info.file;
+ int err;
+ struct kernfs_node *bm = NULL;
+
+ BUILD_BUG_ON(sizeof(bitmap_super_t) != 256);
+
+ BUG_ON(file && mddev->bitmap_info.offset);
+
+ bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL);
+ if (!bitmap)
+ return ERR_PTR(-ENOMEM);
+
+ spin_lock_init(&bitmap->counts.lock);
+ atomic_set(&bitmap->pending_writes, 0);
+ init_waitqueue_head(&bitmap->write_wait);
+ init_waitqueue_head(&bitmap->overflow_wait);
+ init_waitqueue_head(&bitmap->behind_wait);
+
+ bitmap->mddev = mddev;
+ bitmap->cluster_slot = slot;
+
+ if (mddev->kobj.sd)
+ bm = sysfs_get_dirent(mddev->kobj.sd, "bitmap");
+ if (bm) {
+ bitmap->sysfs_can_clear = sysfs_get_dirent(bm, "can_clear");
+ sysfs_put(bm);
+ } else
+ bitmap->sysfs_can_clear = NULL;
+
+ bitmap->storage.file = file;
+ if (file) {
+ get_file(file);
+ /* As future accesses to this file will use bmap,
+ * and bypass the page cache, we must sync the file
+ * first.
+ */
+ vfs_fsync(file, 1);
+ }
+ /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
+ if (!mddev->bitmap_info.external) {
+ /*
+ * If 'MD_ARRAY_FIRST_USE' is set, then device-mapper is
+ * instructing us to create a new on-disk bitmap instance.
+ */
+ if (test_and_clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags))
+ err = bitmap_new_disk_sb(bitmap);
+ else
+ err = bitmap_read_sb(bitmap);
+ } else {
+ err = 0;
+ if (mddev->bitmap_info.chunksize == 0 ||
+ mddev->bitmap_info.daemon_sleep == 0)
+ /* chunksize and time_base need to be
+ * set first. */
+ err = -EINVAL;
+ }
+ if (err)
+ goto error;
+
+ bitmap->daemon_lastrun = jiffies;
+ err = bitmap_resize(bitmap, blocks, mddev->bitmap_info.chunksize, 1);
+ if (err)
+ goto error;
+
+ pr_debug("created bitmap (%lu pages) for device %s\n",
+ bitmap->counts.pages, bmname(bitmap));
+
+ err = test_bit(BITMAP_WRITE_ERROR, &bitmap->flags) ? -EIO : 0;
+ if (err)
+ goto error;
+
+ return bitmap;
+ error:
+ bitmap_free(bitmap);
+ return ERR_PTR(err);
+}
+
+int bitmap_load(struct mddev *mddev)
+{
+ int err = 0;
+ sector_t start = 0;
+ sector_t sector = 0;
+ struct bitmap *bitmap = mddev->bitmap;
+
+ if (!bitmap)
+ goto out;
+
+ if (mddev_is_clustered(mddev))
+ md_cluster_ops->load_bitmaps(mddev, mddev->bitmap_info.nodes);
+
+ /* Clear out old bitmap info first: Either there is none, or we
+ * are resuming after someone else has possibly changed things,
+ * so we should forget old cached info.
+ * All chunks should be clean, but some might need_sync.
+ */
+ while (sector < mddev->resync_max_sectors) {
+ sector_t blocks;
+ bitmap_start_sync(bitmap, sector, &blocks, 0);
+ sector += blocks;
+ }
+ bitmap_close_sync(bitmap);
+
+ if (mddev->degraded == 0
+ || bitmap->events_cleared == mddev->events)
+ /* no need to keep dirty bits to optimise a
+ * re-add of a missing device */
+ start = mddev->recovery_cp;
+
+ mutex_lock(&mddev->bitmap_info.mutex);
+ err = bitmap_init_from_disk(bitmap, start);
+ mutex_unlock(&mddev->bitmap_info.mutex);
+
+ if (err)
+ goto out;
+ clear_bit(BITMAP_STALE, &bitmap->flags);
+
+ /* Kick recovery in case any bits were set */
+ set_bit(MD_RECOVERY_NEEDED, &bitmap->mddev->recovery);
+
+ mddev->thread->timeout = mddev->bitmap_info.daemon_sleep;
+ md_wakeup_thread(mddev->thread);
+
+ bitmap_update_sb(bitmap);
+
+ if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
+ err = -EIO;
+out:
+ return err;
+}
+EXPORT_SYMBOL_GPL(bitmap_load);
+
+struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot)
+{
+ int rv = 0;
+ struct bitmap *bitmap;
+
+ bitmap = bitmap_create(mddev, slot);
+ if (IS_ERR(bitmap)) {
+ rv = PTR_ERR(bitmap);
+ return ERR_PTR(rv);
+ }
+
+ rv = bitmap_init_from_disk(bitmap, 0);
+ if (rv) {
+ bitmap_free(bitmap);
+ return ERR_PTR(rv);
+ }
+
+ return bitmap;
+}
+EXPORT_SYMBOL(get_bitmap_from_slot);
+
+/* Loads the bitmap associated with slot and copies the resync information
+ * to our bitmap
+ */
+int bitmap_copy_from_slot(struct mddev *mddev, int slot,
+ sector_t *low, sector_t *high, bool clear_bits)
+{
+ int rv = 0, i, j;
+ sector_t block, lo = 0, hi = 0;
+ struct bitmap_counts *counts;
+ struct bitmap *bitmap;
+
+ bitmap = get_bitmap_from_slot(mddev, slot);
+ if (IS_ERR(bitmap)) {
+ pr_err("%s can't get bitmap from slot %d\n", __func__, slot);
+ return -1;
+ }
+
+ counts = &bitmap->counts;
+ for (j = 0; j < counts->chunks; j++) {
+ block = (sector_t)j << counts->chunkshift;
+ if (bitmap_file_test_bit(bitmap, block)) {
+ if (!lo)
+ lo = block;
+ hi = block;
+ bitmap_file_clear_bit(bitmap, block);
+ bitmap_set_memory_bits(mddev->bitmap, block, 1);
+ bitmap_file_set_bit(mddev->bitmap, block);
+ }
+ }
+
+ if (clear_bits) {
+ bitmap_update_sb(bitmap);
+ /* BITMAP_PAGE_PENDING is set, but bitmap_unplug needs
+ * BITMAP_PAGE_DIRTY or _NEEDWRITE to write ... */
+ for (i = 0; i < bitmap->storage.file_pages; i++)
+ if (test_page_attr(bitmap, i, BITMAP_PAGE_PENDING))
+ set_page_attr(bitmap, i, BITMAP_PAGE_NEEDWRITE);
+ bitmap_unplug(bitmap);
+ }
+ bitmap_unplug(mddev->bitmap);
+ *low = lo;
+ *high = hi;
+
+ return rv;
+}
+EXPORT_SYMBOL_GPL(bitmap_copy_from_slot);
+
+
+void bitmap_status(struct seq_file *seq, struct bitmap *bitmap)
+{
+ unsigned long chunk_kb;
+ struct bitmap_counts *counts;
+
+ if (!bitmap)
+ return;
+
+ counts = &bitmap->counts;
+
+ chunk_kb = bitmap->mddev->bitmap_info.chunksize >> 10;
+ seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
+ "%lu%s chunk",
+ counts->pages - counts->missing_pages,
+ counts->pages,
+ (counts->pages - counts->missing_pages)
+ << (PAGE_SHIFT - 10),
+ chunk_kb ? chunk_kb : bitmap->mddev->bitmap_info.chunksize,
+ chunk_kb ? "KB" : "B");
+ if (bitmap->storage.file) {
+ seq_printf(seq, ", file: ");
+ seq_file_path(seq, bitmap->storage.file, " \t\n");
+ }
+
+ seq_printf(seq, "\n");
+}
+
+int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
+ int chunksize, int init)
+{
+ /* If chunk_size is 0, choose an appropriate chunk size.
+ * Then possibly allocate new storage space.
+ * Then quiesce, copy bits, replace bitmap, and re-start
+ *
+ * This function is called both to set up the initial bitmap
+ * and to resize the bitmap while the array is active.
+ * If this happens as a result of the array being resized,
+ * chunksize will be zero, and we need to choose a suitable
+ * chunksize, otherwise we use what we are given.
+ */
+ struct bitmap_storage store;
+ struct bitmap_counts old_counts;
+ unsigned long chunks;
+ sector_t block;
+ sector_t old_blocks, new_blocks;
+ int chunkshift;
+ int ret = 0;
+ long pages;
+ struct bitmap_page *new_bp;
+
+ if (bitmap->storage.file && !init) {
+ pr_info("md: cannot resize file-based bitmap\n");
+ return -EINVAL;
+ }
+
+ if (chunksize == 0) {
+ /* If there is enough space, leave the chunk size unchanged,
+ * else increase by factor of two until there is enough space.
+ */
+ long bytes;
+ long space = bitmap->mddev->bitmap_info.space;
+
+ if (space == 0) {
+ /* We don't know how much space there is, so limit
+ * to current size - in sectors.
+ */
+ bytes = DIV_ROUND_UP(bitmap->counts.chunks, 8);
+ if (!bitmap->mddev->bitmap_info.external)
+ bytes += sizeof(bitmap_super_t);
+ space = DIV_ROUND_UP(bytes, 512);
+ bitmap->mddev->bitmap_info.space = space;
+ }
+ chunkshift = bitmap->counts.chunkshift;
+ chunkshift--;
+ do {
+ /* 'chunkshift' is shift from block size to chunk size */
+ chunkshift++;
+ chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << chunkshift);
+ bytes = DIV_ROUND_UP(chunks, 8);
+ if (!bitmap->mddev->bitmap_info.external)
+ bytes += sizeof(bitmap_super_t);
+ } while (bytes > (space << 9));
+ } else
+ chunkshift = ffz(~chunksize) - BITMAP_BLOCK_SHIFT;
+
+ chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << chunkshift);
+ memset(&store, 0, sizeof(store));
+ if (bitmap->mddev->bitmap_info.offset || bitmap->mddev->bitmap_info.file)
+ ret = bitmap_storage_alloc(&store, chunks,
+ !bitmap->mddev->bitmap_info.external,
+ mddev_is_clustered(bitmap->mddev)
+ ? bitmap->cluster_slot : 0);
+ if (ret) {
+ bitmap_file_unmap(&store);
+ goto err;
+ }
+
+ pages = DIV_ROUND_UP(chunks, PAGE_COUNTER_RATIO);
+
+ new_bp = kzalloc(pages * sizeof(*new_bp), GFP_KERNEL);
+ ret = -ENOMEM;
+ if (!new_bp) {
+ bitmap_file_unmap(&store);
+ goto err;
+ }
+
+ if (!init)
+ bitmap->mddev->pers->quiesce(bitmap->mddev, 1);
+
+ store.file = bitmap->storage.file;
+ bitmap->storage.file = NULL;
+
+ if (store.sb_page && bitmap->storage.sb_page)
+ memcpy(page_address(store.sb_page),
+ page_address(bitmap->storage.sb_page),
+ sizeof(bitmap_super_t));
+ bitmap_file_unmap(&bitmap->storage);
+ bitmap->storage = store;
+
+ old_counts = bitmap->counts;
+ bitmap->counts.bp = new_bp;
+ bitmap->counts.pages = pages;
+ bitmap->counts.missing_pages = pages;
+ bitmap->counts.chunkshift = chunkshift;
+ bitmap->counts.chunks = chunks;
+ bitmap->mddev->bitmap_info.chunksize = 1 << (chunkshift +
+ BITMAP_BLOCK_SHIFT);
+
+ blocks = min(old_counts.chunks << old_counts.chunkshift,
+ chunks << chunkshift);
+
+ spin_lock_irq(&bitmap->counts.lock);
+ /* For cluster raid, need to pre-allocate bitmap */
+ if (mddev_is_clustered(bitmap->mddev)) {
+ unsigned long page;
+ for (page = 0; page < pages; page++) {
+ ret = bitmap_checkpage(&bitmap->counts, page, 1, 1);
+ if (ret) {
+ unsigned long k;
+
+ /* deallocate the page memory */
+ for (k = 0; k < page; k++) {
+ kfree(new_bp[k].map);
+ }
+
+ /* restore some fields from old_counts */
+ bitmap->counts.bp = old_counts.bp;
+ bitmap->counts.pages = old_counts.pages;
+ bitmap->counts.missing_pages = old_counts.pages;
+ bitmap->counts.chunkshift = old_counts.chunkshift;
+ bitmap->counts.chunks = old_counts.chunks;
+ bitmap->mddev->bitmap_info.chunksize = 1 << (old_counts.chunkshift +
+ BITMAP_BLOCK_SHIFT);
+ blocks = old_counts.chunks << old_counts.chunkshift;
+ pr_warn("Could not pre-allocate in-memory bitmap for cluster raid\n");
+ break;
+ } else
+ bitmap->counts.bp[page].count += 1;
+ }
+ }
+
+ for (block = 0; block < blocks; ) {
+ bitmap_counter_t *bmc_old, *bmc_new;
+ int set;
+
+ bmc_old = bitmap_get_counter(&old_counts, block,
+ &old_blocks, 0);
+ set = bmc_old && NEEDED(*bmc_old);
+
+ if (set) {
+ bmc_new = bitmap_get_counter(&bitmap->counts, block,
+ &new_blocks, 1);
+ if (*bmc_new == 0) {
+ /* need to set on-disk bits too. */
+ sector_t end = block + new_blocks;
+ sector_t start = block >> chunkshift;
+ start <<= chunkshift;
+ while (start < end) {
+ bitmap_file_set_bit(bitmap, block);
+ start += 1 << chunkshift;
+ }
+ *bmc_new = 2;
+ bitmap_count_page(&bitmap->counts,
+ block, 1);
+ bitmap_set_pending(&bitmap->counts,
+ block);
+ }
+ *bmc_new |= NEEDED_MASK;
+ if (new_blocks < old_blocks)
+ old_blocks = new_blocks;
+ }
+ block += old_blocks;
+ }
+
+ if (!init) {
+ int i;
+ while (block < (chunks << chunkshift)) {
+ bitmap_counter_t *bmc;
+ bmc = bitmap_get_counter(&bitmap->counts, block,
+ &new_blocks, 1);
+ if (bmc) {
+ /* new space. It needs to be resynced, so
+ * we set NEEDED_MASK.
+ */
+ if (*bmc == 0) {
+ *bmc = NEEDED_MASK | 2;
+ bitmap_count_page(&bitmap->counts,
+ block, 1);
+ bitmap_set_pending(&bitmap->counts,
+ block);
+ }
+ }
+ block += new_blocks;
+ }
+ for (i = 0; i < bitmap->storage.file_pages; i++)
+ set_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
+ }
+ spin_unlock_irq(&bitmap->counts.lock);
+
+ if (!init) {
+ bitmap_unplug(bitmap);
+ bitmap->mddev->pers->quiesce(bitmap->mddev, 0);
+ }
+ ret = 0;
+err:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(bitmap_resize);
+
+static ssize_t
+location_show(struct mddev *mddev, char *page)
+{
+ ssize_t len;
+ if (mddev->bitmap_info.file)
+ len = sprintf(page, "file");
+ else if (mddev->bitmap_info.offset)
+ len = sprintf(page, "%+lld", (long long)mddev->bitmap_info.offset);
+ else
+ len = sprintf(page, "none");
+ len += sprintf(page+len, "\n");
+ return len;
+}
+
+static ssize_t
+location_store(struct mddev *mddev, const char *buf, size_t len)
+{
+ int rv;
+
+ rv = mddev_lock(mddev);
+ if (rv)
+ return rv;
+ if (mddev->pers) {
+ if (!mddev->pers->quiesce) {
+ rv = -EBUSY;
+ goto out;
+ }
+ if (mddev->recovery || mddev->sync_thread) {
+ rv = -EBUSY;
+ goto out;
+ }
+ }
+
+ if (mddev->bitmap || mddev->bitmap_info.file ||
+ mddev->bitmap_info.offset) {
+ /* bitmap already configured. Only option is to clear it */
+ if (strncmp(buf, "none", 4) != 0) {
+ rv = -EBUSY;
+ goto out;
+ }
+ if (mddev->pers) {
+ mddev->pers->quiesce(mddev, 1);
+ bitmap_destroy(mddev);
+ mddev->pers->quiesce(mddev, 0);
+ }
+ mddev->bitmap_info.offset = 0;
+ if (mddev->bitmap_info.file) {
+ struct file *f = mddev->bitmap_info.file;
+ mddev->bitmap_info.file = NULL;
+ fput(f);
+ }
+ } else {
+ /* No bitmap, OK to set a location */
+ long long offset;
+ if (strncmp(buf, "none", 4) == 0)
+ /* nothing to be done */;
+ else if (strncmp(buf, "file:", 5) == 0) {
+ /* Not supported yet */
+ rv = -EINVAL;
+ goto out;
+ } else {
+ if (buf[0] == '+')
+ rv = kstrtoll(buf+1, 10, &offset);
+ else
+ rv = kstrtoll(buf, 10, &offset);
+ if (rv)
+ goto out;
+ if (offset == 0) {
+ rv = -EINVAL;
+ goto out;
+ }
+ if (mddev->bitmap_info.external == 0 &&
+ mddev->major_version == 0 &&
+ offset != mddev->bitmap_info.default_offset) {
+ rv = -EINVAL;
+ goto out;
+ }
+ mddev->bitmap_info.offset = offset;
+ if (mddev->pers) {
+ struct bitmap *bitmap;
+ mddev->pers->quiesce(mddev, 1);
+ bitmap = bitmap_create(mddev, -1);
+ if (IS_ERR(bitmap))
+ rv = PTR_ERR(bitmap);
+ else {
+ mddev->bitmap = bitmap;
+ rv = bitmap_load(mddev);
+ if (rv)
+ mddev->bitmap_info.offset = 0;
+ }
+ mddev->pers->quiesce(mddev, 0);
+ if (rv) {
+ bitmap_destroy(mddev);
+ goto out;
+ }
+ }
+ }
+ }
+ if (!mddev->external) {
+ /* Ensure new bitmap info is stored in
+ * metadata promptly.
+ */
+ set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
+ md_wakeup_thread(mddev->thread);
+ }
+ rv = 0;
+out:
+ mddev_unlock(mddev);
+ if (rv)
+ return rv;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_location =
+__ATTR(location, S_IRUGO|S_IWUSR, location_show, location_store);
+
+/* 'bitmap/space' is the space available at 'location' for the
+ * bitmap. This allows the kernel to know when it is safe to
+ * resize the bitmap to match a resized array.
+ */
+static ssize_t
+space_show(struct mddev *mddev, char *page)
+{
+ return sprintf(page, "%lu\n", mddev->bitmap_info.space);
+}
+
+static ssize_t
+space_store(struct mddev *mddev, const char *buf, size_t len)
+{
+ unsigned long sectors;
+ int rv;
+
+ rv = kstrtoul(buf, 10, §ors);
+ if (rv)
+ return rv;
+
+ if (sectors == 0)
+ return -EINVAL;
+
+ if (mddev->bitmap &&
+ sectors < (mddev->bitmap->storage.bytes + 511) >> 9)
+ return -EFBIG; /* Bitmap is too big for this small space */
+
+ /* could make sure it isn't too big, but that isn't really
+ * needed - user-space should be careful.
+ */
+ mddev->bitmap_info.space = sectors;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_space =
+__ATTR(space, S_IRUGO|S_IWUSR, space_show, space_store);
+
+static ssize_t
+timeout_show(struct mddev *mddev, char *page)
+{
+ ssize_t len;
+ unsigned long secs = mddev->bitmap_info.daemon_sleep / HZ;
+ unsigned long jifs = mddev->bitmap_info.daemon_sleep % HZ;
+
+ len = sprintf(page, "%lu", secs);
+ if (jifs)
+ len += sprintf(page+len, ".%03u", jiffies_to_msecs(jifs));
+ len += sprintf(page+len, "\n");
+ return len;
+}
+
+static ssize_t
+timeout_store(struct mddev *mddev, const char *buf, size_t len)
+{
+ /* timeout can be set at any time */
+ unsigned long timeout;
+ int rv = strict_strtoul_scaled(buf, &timeout, 4);
+ if (rv)
+ return rv;
+
+ /* just to make sure we don't overflow... */
+ if (timeout >= LONG_MAX / HZ)
+ return -EINVAL;
+
+ timeout = timeout * HZ / 10000;
+
+ if (timeout >= MAX_SCHEDULE_TIMEOUT)
+ timeout = MAX_SCHEDULE_TIMEOUT-1;
+ if (timeout < 1)
+ timeout = 1;
+ mddev->bitmap_info.daemon_sleep = timeout;
+ if (mddev->thread) {
+ /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
+ * the bitmap is all clean and we don't need to
+ * adjust the timeout right now
+ */
+ if (mddev->thread->timeout < MAX_SCHEDULE_TIMEOUT) {
+ mddev->thread->timeout = timeout;
+ md_wakeup_thread(mddev->thread);
+ }
+ }
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_timeout =
+__ATTR(time_base, S_IRUGO|S_IWUSR, timeout_show, timeout_store);
+
+static ssize_t
+backlog_show(struct mddev *mddev, char *page)
+{
+ return sprintf(page, "%lu\n", mddev->bitmap_info.max_write_behind);
+}
+
+static ssize_t
+backlog_store(struct mddev *mddev, const char *buf, size_t len)
+{
+ unsigned long backlog;
+ int rv = kstrtoul(buf, 10, &backlog);
+ if (rv)
+ return rv;
+ if (backlog > COUNTER_MAX)
+ return -EINVAL;
+ mddev->bitmap_info.max_write_behind = backlog;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_backlog =
+__ATTR(backlog, S_IRUGO|S_IWUSR, backlog_show, backlog_store);
+
+static ssize_t
+chunksize_show(struct mddev *mddev, char *page)
+{
+ return sprintf(page, "%lu\n", mddev->bitmap_info.chunksize);
+}
+
+static ssize_t
+chunksize_store(struct mddev *mddev, const char *buf, size_t len)
+{
+ /* Can only be changed when no bitmap is active */
+ int rv;
+ unsigned long csize;
+ if (mddev->bitmap)
+ return -EBUSY;
+ rv = kstrtoul(buf, 10, &csize);
+ if (rv)
+ return rv;
+ if (csize < 512 ||
+ !is_power_of_2(csize))
+ return -EINVAL;
+ mddev->bitmap_info.chunksize = csize;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_chunksize =
+__ATTR(chunksize, S_IRUGO|S_IWUSR, chunksize_show, chunksize_store);
+
+static ssize_t metadata_show(struct mddev *mddev, char *page)
+{
+ if (mddev_is_clustered(mddev))
+ return sprintf(page, "clustered\n");
+ return sprintf(page, "%s\n", (mddev->bitmap_info.external
+ ? "external" : "internal"));
+}
+
+static ssize_t metadata_store(struct mddev *mddev, const char *buf, size_t len)
+{
+ if (mddev->bitmap ||
+ mddev->bitmap_info.file ||
+ mddev->bitmap_info.offset)
+ return -EBUSY;
+ if (strncmp(buf, "external", 8) == 0)
+ mddev->bitmap_info.external = 1;
+ else if ((strncmp(buf, "internal", 8) == 0) ||
+ (strncmp(buf, "clustered", 9) == 0))
+ mddev->bitmap_info.external = 0;
+ else
+ return -EINVAL;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_metadata =
+__ATTR(metadata, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
+
+static ssize_t can_clear_show(struct mddev *mddev, char *page)
+{
+ int len;
+ spin_lock(&mddev->lock);
+ if (mddev->bitmap)
+ len = sprintf(page, "%s\n", (mddev->bitmap->need_sync ?
+ "false" : "true"));
+ else
+ len = sprintf(page, "\n");
+ spin_unlock(&mddev->lock);
+ return len;
+}
+
+static ssize_t can_clear_store(struct mddev *mddev, const char *buf, size_t len)
+{
+ if (mddev->bitmap == NULL)
+ return -ENOENT;
+ if (strncmp(buf, "false", 5) == 0)
+ mddev->bitmap->need_sync = 1;
+ else if (strncmp(buf, "true", 4) == 0) {
+ if (mddev->degraded)
+ return -EBUSY;
+ mddev->bitmap->need_sync = 0;
+ } else
+ return -EINVAL;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_can_clear =
+__ATTR(can_clear, S_IRUGO|S_IWUSR, can_clear_show, can_clear_store);
+
+static ssize_t
+behind_writes_used_show(struct mddev *mddev, char *page)
+{
+ ssize_t ret;
+ spin_lock(&mddev->lock);
+ if (mddev->bitmap == NULL)
+ ret = sprintf(page, "0\n");
+ else
+ ret = sprintf(page, "%lu\n",
+ mddev->bitmap->behind_writes_used);
+ spin_unlock(&mddev->lock);
+ return ret;
+}
+
+static ssize_t
+behind_writes_used_reset(struct mddev *mddev, const char *buf, size_t len)
+{
+ if (mddev->bitmap)
+ mddev->bitmap->behind_writes_used = 0;
+ return len;
+}
+
+static struct md_sysfs_entry max_backlog_used =
+__ATTR(max_backlog_used, S_IRUGO | S_IWUSR,
+ behind_writes_used_show, behind_writes_used_reset);
+
+static struct attribute *md_bitmap_attrs[] = {
+ &bitmap_location.attr,
+ &bitmap_space.attr,
+ &bitmap_timeout.attr,
+ &bitmap_backlog.attr,
+ &bitmap_chunksize.attr,
+ &bitmap_metadata.attr,
+ &bitmap_can_clear.attr,
+ &max_backlog_used.attr,
+ NULL
+};
+struct attribute_group md_bitmap_group = {
+ .name = "bitmap",
+ .attrs = md_bitmap_attrs,
+};
+
--- /dev/null
+/*
+ * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
+ *
+ * additions: Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
+ */
+#ifndef BITMAP_H
+#define BITMAP_H 1
+
+#define BITMAP_MAJOR_LO 3
+/* version 4 insists the bitmap is in little-endian order
+ * with version 3, it is host-endian which is non-portable
+ * Version 5 is currently set only for clustered devices
+ */
+#define BITMAP_MAJOR_HI 4
+#define BITMAP_MAJOR_CLUSTERED 5
+#define BITMAP_MAJOR_HOSTENDIAN 3
+
+/*
+ * in-memory bitmap:
+ *
+ * Use 16 bit block counters to track pending writes to each "chunk".
+ * The 2 high order bits are special-purpose, the first is a flag indicating
+ * whether a resync is needed. The second is a flag indicating whether a
+ * resync is active.
+ * This means that the counter is actually 14 bits:
+ *
+ * +--------+--------+------------------------------------------------+
+ * | resync | resync | counter |
+ * | needed | active | |
+ * | (0-1) | (0-1) | (0-16383) |
+ * +--------+--------+------------------------------------------------+
+ *
+ * The "resync needed" bit is set when:
+ * a '1' bit is read from storage at startup.
+ * a write request fails on some drives
+ * a resync is aborted on a chunk with 'resync active' set
+ * It is cleared (and resync-active set) when a resync starts across all drives
+ * of the chunk.
+ *
+ *
+ * The "resync active" bit is set when:
+ * a resync is started on all drives, and resync_needed is set.
+ * resync_needed will be cleared (as long as resync_active wasn't already set).
+ * It is cleared when a resync completes.
+ *
+ * The counter counts pending write requests, plus the on-disk bit.
+ * When the counter is '1' and the resync bits are clear, the on-disk
+ * bit can be cleared as well, thus setting the counter to 0.
+ * When we set a bit, or in the counter (to start a write), if the fields is
+ * 0, we first set the disk bit and set the counter to 1.
+ *
+ * If the counter is 0, the on-disk bit is clear and the stripe is clean
+ * Anything that dirties the stripe pushes the counter to 2 (at least)
+ * and sets the on-disk bit (lazily).
+ * If a periodic sweep find the counter at 2, it is decremented to 1.
+ * If the sweep find the counter at 1, the on-disk bit is cleared and the
+ * counter goes to zero.
+ *
+ * Also, we'll hijack the "map" pointer itself and use it as two 16 bit block
+ * counters as a fallback when "page" memory cannot be allocated:
+ *
+ * Normal case (page memory allocated):
+ *
+ * page pointer (32-bit)
+ *
+ * [ ] ------+
+ * |
+ * +-------> [ ][ ]..[ ] (4096 byte page == 2048 counters)
+ * c1 c2 c2048
+ *
+ * Hijacked case (page memory allocation failed):
+ *
+ * hijacked page pointer (32-bit)
+ *
+ * [ ][ ] (no page memory allocated)
+ * counter #1 (16-bit) counter #2 (16-bit)
+ *
+ */
+
+#ifdef __KERNEL__
+
+#define PAGE_BITS (PAGE_SIZE << 3)
+#define PAGE_BIT_SHIFT (PAGE_SHIFT + 3)
+
+typedef __u16 bitmap_counter_t;
+#define COUNTER_BITS 16
+#define COUNTER_BIT_SHIFT 4
+#define COUNTER_BYTE_SHIFT (COUNTER_BIT_SHIFT - 3)
+
+#define NEEDED_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 1)))
+#define RESYNC_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 2)))
+#define COUNTER_MAX ((bitmap_counter_t) RESYNC_MASK - 1)
+#define NEEDED(x) (((bitmap_counter_t) x) & NEEDED_MASK)
+#define RESYNC(x) (((bitmap_counter_t) x) & RESYNC_MASK)
+#define COUNTER(x) (((bitmap_counter_t) x) & COUNTER_MAX)
+
+/* how many counters per page? */
+#define PAGE_COUNTER_RATIO (PAGE_BITS / COUNTER_BITS)
+/* same, except a shift value for more efficient bitops */
+#define PAGE_COUNTER_SHIFT (PAGE_BIT_SHIFT - COUNTER_BIT_SHIFT)
+/* same, except a mask value for more efficient bitops */
+#define PAGE_COUNTER_MASK (PAGE_COUNTER_RATIO - 1)
+
+#define BITMAP_BLOCK_SHIFT 9
+
+#endif
+
+/*
+ * bitmap structures:
+ */
+
+#define BITMAP_MAGIC 0x6d746962
+
+/* use these for bitmap->flags and bitmap->sb->state bit-fields */
+enum bitmap_state {
+ BITMAP_STALE = 1, /* the bitmap file is out of date or had -EIO */
+ BITMAP_WRITE_ERROR = 2, /* A write error has occurred */
+ BITMAP_HOSTENDIAN =15,
+};
+
+/* the superblock at the front of the bitmap file -- little endian */
+typedef struct bitmap_super_s {
+ __le32 magic; /* 0 BITMAP_MAGIC */
+ __le32 version; /* 4 the bitmap major for now, could change... */
+ __u8 uuid[16]; /* 8 128 bit uuid - must match md device uuid */
+ __le64 events; /* 24 event counter for the bitmap (1)*/
+ __le64 events_cleared;/*32 event counter when last bit cleared (2) */
+ __le64 sync_size; /* 40 the size of the md device's sync range(3) */
+ __le32 state; /* 48 bitmap state information */
+ __le32 chunksize; /* 52 the bitmap chunk size in bytes */
+ __le32 daemon_sleep; /* 56 seconds between disk flushes */
+ __le32 write_behind; /* 60 number of outstanding write-behind writes */
+ __le32 sectors_reserved; /* 64 number of 512-byte sectors that are
+ * reserved for the bitmap. */
+ __le32 nodes; /* 68 the maximum number of nodes in cluster. */
+ __u8 cluster_name[64]; /* 72 cluster name to which this md belongs */
+ __u8 pad[256 - 136]; /* set to zero */
+} bitmap_super_t;
+
+/* notes:
+ * (1) This event counter is updated before the eventcounter in the md superblock
+ * When a bitmap is loaded, it is only accepted if this event counter is equal
+ * to, or one greater than, the event counter in the superblock.
+ * (2) This event counter is updated when the other one is *if*and*only*if* the
+ * array is not degraded. As bits are not cleared when the array is degraded,
+ * this represents the last time that any bits were cleared.
+ * If a device is being added that has an event count with this value or
+ * higher, it is accepted as conforming to the bitmap.
+ * (3)This is the number of sectors represented by the bitmap, and is the range that
+ * resync happens across. For raid1 and raid5/6 it is the size of individual
+ * devices. For raid10 it is the size of the array.
+ */
+
+#ifdef __KERNEL__
+
+/* the in-memory bitmap is represented by bitmap_pages */
+struct bitmap_page {
+ /*
+ * map points to the actual memory page
+ */
+ char *map;
+ /*
+ * in emergencies (when map cannot be alloced), hijack the map
+ * pointer and use it as two counters itself
+ */
+ unsigned int hijacked:1;
+ /*
+ * If any counter in this page is '1' or '2' - and so could be
+ * cleared then that page is marked as 'pending'
+ */
+ unsigned int pending:1;
+ /*
+ * count of dirty bits on the page
+ */
+ unsigned int count:30;
+};
+
+/* the main bitmap structure - one per mddev */
+struct bitmap {
+
+ struct bitmap_counts {
+ spinlock_t lock;
+ struct bitmap_page *bp;
+ unsigned long pages; /* total number of pages
+ * in the bitmap */
+ unsigned long missing_pages; /* number of pages
+ * not yet allocated */
+ unsigned long chunkshift; /* chunksize = 2^chunkshift
+ * (for bitops) */
+ unsigned long chunks; /* Total number of data
+ * chunks for the array */
+ } counts;
+
+ struct mddev *mddev; /* the md device that the bitmap is for */
+
+ __u64 events_cleared;
+ int need_sync;
+
+ struct bitmap_storage {
+ struct file *file; /* backing disk file */
+ struct page *sb_page; /* cached copy of the bitmap
+ * file superblock */
+ struct page **filemap; /* list of cache pages for
+ * the file */
+ unsigned long *filemap_attr; /* attributes associated
+ * w/ filemap pages */
+ unsigned long file_pages; /* number of pages in the file*/
+ unsigned long bytes; /* total bytes in the bitmap */
+ } storage;
+
+ unsigned long flags;
+
+ int allclean;
+
+ atomic_t behind_writes;
+ unsigned long behind_writes_used; /* highest actual value at runtime */
+
+ /*
+ * the bitmap daemon - periodically wakes up and sweeps the bitmap
+ * file, cleaning up bits and flushing out pages to disk as necessary
+ */
+ unsigned long daemon_lastrun; /* jiffies of last run */
+ unsigned long last_end_sync; /* when we lasted called end_sync to
+ * update bitmap with resync progress */
+
+ atomic_t pending_writes; /* pending writes to the bitmap file */
+ wait_queue_head_t write_wait;
+ wait_queue_head_t overflow_wait;
+ wait_queue_head_t behind_wait;
+
+ struct kernfs_node *sysfs_can_clear;
+ int cluster_slot; /* Slot offset for clustered env */
+};
+
+/* the bitmap API */
+
+/* these are used only by md/bitmap */
+struct bitmap *bitmap_create(struct mddev *mddev, int slot);
+int bitmap_load(struct mddev *mddev);
+void bitmap_flush(struct mddev *mddev);
+void bitmap_destroy(struct mddev *mddev);
+
+void bitmap_print_sb(struct bitmap *bitmap);
+void bitmap_update_sb(struct bitmap *bitmap);
+void bitmap_status(struct seq_file *seq, struct bitmap *bitmap);
+
+int bitmap_setallbits(struct bitmap *bitmap);
+void bitmap_write_all(struct bitmap *bitmap);
+
+void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e);
+
+/* these are exported */
+int bitmap_startwrite(struct bitmap *bitmap, sector_t offset,
+ unsigned long sectors, int behind);
+void bitmap_endwrite(struct bitmap *bitmap, sector_t offset,
+ unsigned long sectors, int success, int behind);
+int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int degraded);
+void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted);
+void bitmap_close_sync(struct bitmap *bitmap);
+void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector, bool force);
+void bitmap_sync_with_cluster(struct mddev *mddev,
+ sector_t old_lo, sector_t old_hi,
+ sector_t new_lo, sector_t new_hi);
+
+void bitmap_unplug(struct bitmap *bitmap);
+void bitmap_daemon_work(struct mddev *mddev);
+
+int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
+ int chunksize, int init);
+struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot);
+int bitmap_copy_from_slot(struct mddev *mddev, int slot,
+ sector_t *lo, sector_t *hi, bool clear_bits);
+void bitmap_free(struct bitmap *bitmap);
+void bitmap_wait_behind_writes(struct mddev *mddev);
+#endif
+
+#endif
#include <linux/sched.h>
#include <linux/raid/md_p.h>
#include "md.h"
-#include "bitmap.h"
+#include "md-bitmap.h"
#include "md-cluster.h"
#define LVB_SIZE 64
--- /dev/null
+/*
+ * faulty.c : Multiple Devices driver for Linux
+ *
+ * Copyright (C) 2004 Neil Brown
+ *
+ * fautly-device-simulator personality for md
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * You should have received a copy of the GNU General Public License
+ * (for example /usr/src/linux/COPYING); if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+/*
+ * The "faulty" personality causes some requests to fail.
+ *
+ * Possible failure modes are:
+ * reads fail "randomly" but succeed on retry
+ * writes fail "randomly" but succeed on retry
+ * reads for some address fail and then persist until a write
+ * reads for some address fail and then persist irrespective of write
+ * writes for some address fail and persist
+ * all writes fail
+ *
+ * Different modes can be active at a time, but only
+ * one can be set at array creation. Others can be added later.
+ * A mode can be one-shot or recurrent with the recurrence being
+ * once in every N requests.
+ * The bottom 5 bits of the "layout" indicate the mode. The
+ * remainder indicate a period, or 0 for one-shot.
+ *
+ * There is an implementation limit on the number of concurrently
+ * persisting-faulty blocks. When a new fault is requested that would
+ * exceed the limit, it is ignored.
+ * All current faults can be clear using a layout of "0".
+ *
+ * Requests are always sent to the device. If they are to fail,
+ * we clone the bio and insert a new b_end_io into the chain.
+ */
+
+#define WriteTransient 0
+#define ReadTransient 1
+#define WritePersistent 2
+#define ReadPersistent 3
+#define WriteAll 4 /* doesn't go to device */
+#define ReadFixable 5
+#define Modes 6
+
+#define ClearErrors 31
+#define ClearFaults 30
+
+#define AllPersist 100 /* internal use only */
+#define NoPersist 101
+
+#define ModeMask 0x1f
+#define ModeShift 5
+
+#define MaxFault 50
+#include <linux/blkdev.h>
+#include <linux/module.h>
+#include <linux/raid/md_u.h>
+#include <linux/slab.h>
+#include "md.h"
+#include <linux/seq_file.h>
+
+
+static void faulty_fail(struct bio *bio)
+{
+ struct bio *b = bio->bi_private;
+
+ b->bi_iter.bi_size = bio->bi_iter.bi_size;
+ b->bi_iter.bi_sector = bio->bi_iter.bi_sector;
+
+ bio_put(bio);
+
+ bio_io_error(b);
+}
+
+struct faulty_conf {
+ int period[Modes];
+ atomic_t counters[Modes];
+ sector_t faults[MaxFault];
+ int modes[MaxFault];
+ int nfaults;
+ struct md_rdev *rdev;
+};
+
+static int check_mode(struct faulty_conf *conf, int mode)
+{
+ if (conf->period[mode] == 0 &&
+ atomic_read(&conf->counters[mode]) <= 0)
+ return 0; /* no failure, no decrement */
+
+
+ if (atomic_dec_and_test(&conf->counters[mode])) {
+ if (conf->period[mode])
+ atomic_set(&conf->counters[mode], conf->period[mode]);
+ return 1;
+ }
+ return 0;
+}
+
+static int check_sector(struct faulty_conf *conf, sector_t start, sector_t end, int dir)
+{
+ /* If we find a ReadFixable sector, we fix it ... */
+ int i;
+ for (i=0; i<conf->nfaults; i++)
+ if (conf->faults[i] >= start &&
+ conf->faults[i] < end) {
+ /* found it ... */
+ switch (conf->modes[i] * 2 + dir) {
+ case WritePersistent*2+WRITE: return 1;
+ case ReadPersistent*2+READ: return 1;
+ case ReadFixable*2+READ: return 1;
+ case ReadFixable*2+WRITE:
+ conf->modes[i] = NoPersist;
+ return 0;
+ case AllPersist*2+READ:
+ case AllPersist*2+WRITE: return 1;
+ default:
+ return 0;
+ }
+ }
+ return 0;
+}
+
+static void add_sector(struct faulty_conf *conf, sector_t start, int mode)
+{
+ int i;
+ int n = conf->nfaults;
+ for (i=0; i<conf->nfaults; i++)
+ if (conf->faults[i] == start) {
+ switch(mode) {
+ case NoPersist: conf->modes[i] = mode; return;
+ case WritePersistent:
+ if (conf->modes[i] == ReadPersistent ||
+ conf->modes[i] == ReadFixable)
+ conf->modes[i] = AllPersist;
+ else
+ conf->modes[i] = WritePersistent;
+ return;
+ case ReadPersistent:
+ if (conf->modes[i] == WritePersistent)
+ conf->modes[i] = AllPersist;
+ else
+ conf->modes[i] = ReadPersistent;
+ return;
+ case ReadFixable:
+ if (conf->modes[i] == WritePersistent ||
+ conf->modes[i] == ReadPersistent)
+ conf->modes[i] = AllPersist;
+ else
+ conf->modes[i] = ReadFixable;
+ return;
+ }
+ } else if (conf->modes[i] == NoPersist)
+ n = i;
+
+ if (n >= MaxFault)
+ return;
+ conf->faults[n] = start;
+ conf->modes[n] = mode;
+ if (conf->nfaults == n)
+ conf->nfaults = n+1;
+}
+
+static bool faulty_make_request(struct mddev *mddev, struct bio *bio)
+{
+ struct faulty_conf *conf = mddev->private;
+ int failit = 0;
+
+ if (bio_data_dir(bio) == WRITE) {
+ /* write request */
+ if (atomic_read(&conf->counters[WriteAll])) {
+ /* special case - don't decrement, don't generic_make_request,
+ * just fail immediately
+ */
+ bio_io_error(bio);
+ return true;
+ }
+
+ if (check_sector(conf, bio->bi_iter.bi_sector,
+ bio_end_sector(bio), WRITE))
+ failit = 1;
+ if (check_mode(conf, WritePersistent)) {
+ add_sector(conf, bio->bi_iter.bi_sector,
+ WritePersistent);
+ failit = 1;
+ }
+ if (check_mode(conf, WriteTransient))
+ failit = 1;
+ } else {
+ /* read request */
+ if (check_sector(conf, bio->bi_iter.bi_sector,
+ bio_end_sector(bio), READ))
+ failit = 1;
+ if (check_mode(conf, ReadTransient))
+ failit = 1;
+ if (check_mode(conf, ReadPersistent)) {
+ add_sector(conf, bio->bi_iter.bi_sector,
+ ReadPersistent);
+ failit = 1;
+ }
+ if (check_mode(conf, ReadFixable)) {
+ add_sector(conf, bio->bi_iter.bi_sector,
+ ReadFixable);
+ failit = 1;
+ }
+ }
+ if (failit) {
+ struct bio *b = bio_clone_fast(bio, GFP_NOIO, mddev->bio_set);
+
+ bio_set_dev(b, conf->rdev->bdev);
+ b->bi_private = bio;
+ b->bi_end_io = faulty_fail;
+ bio = b;
+ } else
+ bio_set_dev(bio, conf->rdev->bdev);
+
+ generic_make_request(bio);
+ return true;
+}
+
+static void faulty_status(struct seq_file *seq, struct mddev *mddev)
+{
+ struct faulty_conf *conf = mddev->private;
+ int n;
+
+ if ((n=atomic_read(&conf->counters[WriteTransient])) != 0)
+ seq_printf(seq, " WriteTransient=%d(%d)",
+ n, conf->period[WriteTransient]);
+
+ if ((n=atomic_read(&conf->counters[ReadTransient])) != 0)
+ seq_printf(seq, " ReadTransient=%d(%d)",
+ n, conf->period[ReadTransient]);
+
+ if ((n=atomic_read(&conf->counters[WritePersistent])) != 0)
+ seq_printf(seq, " WritePersistent=%d(%d)",
+ n, conf->period[WritePersistent]);
+
+ if ((n=atomic_read(&conf->counters[ReadPersistent])) != 0)
+ seq_printf(seq, " ReadPersistent=%d(%d)",
+ n, conf->period[ReadPersistent]);
+
+
+ if ((n=atomic_read(&conf->counters[ReadFixable])) != 0)
+ seq_printf(seq, " ReadFixable=%d(%d)",
+ n, conf->period[ReadFixable]);
+
+ if ((n=atomic_read(&conf->counters[WriteAll])) != 0)
+ seq_printf(seq, " WriteAll");
+
+ seq_printf(seq, " nfaults=%d", conf->nfaults);
+}
+
+
+static int faulty_reshape(struct mddev *mddev)
+{
+ int mode = mddev->new_layout & ModeMask;
+ int count = mddev->new_layout >> ModeShift;
+ struct faulty_conf *conf = mddev->private;
+
+ if (mddev->new_layout < 0)
+ return 0;
+
+ /* new layout */
+ if (mode == ClearFaults)
+ conf->nfaults = 0;
+ else if (mode == ClearErrors) {
+ int i;
+ for (i=0 ; i < Modes ; i++) {
+ conf->period[i] = 0;
+ atomic_set(&conf->counters[i], 0);
+ }
+ } else if (mode < Modes) {
+ conf->period[mode] = count;
+ if (!count) count++;
+ atomic_set(&conf->counters[mode], count);
+ } else
+ return -EINVAL;
+ mddev->new_layout = -1;
+ mddev->layout = -1; /* makes sure further changes come through */
+ return 0;
+}
+
+static sector_t faulty_size(struct mddev *mddev, sector_t sectors, int raid_disks)
+{
+ WARN_ONCE(raid_disks,
+ "%s does not support generic reshape\n", __func__);
+
+ if (sectors == 0)
+ return mddev->dev_sectors;
+
+ return sectors;
+}
+
+static int faulty_run(struct mddev *mddev)
+{
+ struct md_rdev *rdev;
+ int i;
+ struct faulty_conf *conf;
+
+ if (md_check_no_bitmap(mddev))
+ return -EINVAL;
+
+ conf = kmalloc(sizeof(*conf), GFP_KERNEL);
+ if (!conf)
+ return -ENOMEM;
+
+ for (i=0; i<Modes; i++) {
+ atomic_set(&conf->counters[i], 0);
+ conf->period[i] = 0;
+ }
+ conf->nfaults = 0;
+
+ rdev_for_each(rdev, mddev) {
+ conf->rdev = rdev;
+ disk_stack_limits(mddev->gendisk, rdev->bdev,
+ rdev->data_offset << 9);
+ }
+
+ md_set_array_sectors(mddev, faulty_size(mddev, 0, 0));
+ mddev->private = conf;
+
+ faulty_reshape(mddev);
+
+ return 0;
+}
+
+static void faulty_free(struct mddev *mddev, void *priv)
+{
+ struct faulty_conf *conf = priv;
+
+ kfree(conf);
+}
+
+static struct md_personality faulty_personality =
+{
+ .name = "faulty",
+ .level = LEVEL_FAULTY,
+ .owner = THIS_MODULE,
+ .make_request = faulty_make_request,
+ .run = faulty_run,
+ .free = faulty_free,
+ .status = faulty_status,
+ .check_reshape = faulty_reshape,
+ .size = faulty_size,
+};
+
+static int __init raid_init(void)
+{
+ return register_md_personality(&faulty_personality);
+}
+
+static void raid_exit(void)
+{
+ unregister_md_personality(&faulty_personality);
+}
+
+module_init(raid_init);
+module_exit(raid_exit);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Fault injection personality for MD");
+MODULE_ALIAS("md-personality-10"); /* faulty */
+MODULE_ALIAS("md-faulty");
+MODULE_ALIAS("md-level--5");
--- /dev/null
+/*
+ linear.c : Multiple Devices driver for Linux
+ Copyright (C) 1994-96 Marc ZYNGIER
+ <zyngier@ufr-info-p7.ibp.fr> or
+ <maz@gloups.fdn.fr>
+
+ Linear mode management functions.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ You should have received a copy of the GNU General Public License
+ (for example /usr/src/linux/COPYING); if not, write to the Free
+ Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include <linux/blkdev.h>
+#include <linux/raid/md_u.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <trace/events/block.h>
+#include "md.h"
+#include "md-linear.h"
+
+/*
+ * find which device holds a particular offset
+ */
+static inline struct dev_info *which_dev(struct mddev *mddev, sector_t sector)
+{
+ int lo, mid, hi;
+ struct linear_conf *conf;
+
+ lo = 0;
+ hi = mddev->raid_disks - 1;
+ conf = mddev->private;
+
+ /*
+ * Binary Search
+ */
+
+ while (hi > lo) {
+
+ mid = (hi + lo) / 2;
+ if (sector < conf->disks[mid].end_sector)
+ hi = mid;
+ else
+ lo = mid + 1;
+ }
+
+ return conf->disks + lo;
+}
+
+/*
+ * In linear_congested() conf->raid_disks is used as a copy of
+ * mddev->raid_disks to iterate conf->disks[], because conf->raid_disks
+ * and conf->disks[] are created in linear_conf(), they are always
+ * consitent with each other, but mddev->raid_disks does not.
+ */
+static int linear_congested(struct mddev *mddev, int bits)
+{
+ struct linear_conf *conf;
+ int i, ret = 0;
+
+ rcu_read_lock();
+ conf = rcu_dereference(mddev->private);
+
+ for (i = 0; i < conf->raid_disks && !ret ; i++) {
+ struct request_queue *q = bdev_get_queue(conf->disks[i].rdev->bdev);
+ ret |= bdi_congested(q->backing_dev_info, bits);
+ }
+
+ rcu_read_unlock();
+ return ret;
+}
+
+static sector_t linear_size(struct mddev *mddev, sector_t sectors, int raid_disks)
+{
+ struct linear_conf *conf;
+ sector_t array_sectors;
+
+ conf = mddev->private;
+ WARN_ONCE(sectors || raid_disks,
+ "%s does not support generic reshape\n", __func__);
+ array_sectors = conf->array_sectors;
+
+ return array_sectors;
+}
+
+static struct linear_conf *linear_conf(struct mddev *mddev, int raid_disks)
+{
+ struct linear_conf *conf;
+ struct md_rdev *rdev;
+ int i, cnt;
+ bool discard_supported = false;
+
+ conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(struct dev_info),
+ GFP_KERNEL);
+ if (!conf)
+ return NULL;
+
+ cnt = 0;
+ conf->array_sectors = 0;
+
+ rdev_for_each(rdev, mddev) {
+ int j = rdev->raid_disk;
+ struct dev_info *disk = conf->disks + j;
+ sector_t sectors;
+
+ if (j < 0 || j >= raid_disks || disk->rdev) {
+ pr_warn("md/linear:%s: disk numbering problem. Aborting!\n",
+ mdname(mddev));
+ goto out;
+ }
+
+ disk->rdev = rdev;
+ if (mddev->chunk_sectors) {
+ sectors = rdev->sectors;
+ sector_div(sectors, mddev->chunk_sectors);
+ rdev->sectors = sectors * mddev->chunk_sectors;
+ }
+
+ disk_stack_limits(mddev->gendisk, rdev->bdev,
+ rdev->data_offset << 9);
+
+ conf->array_sectors += rdev->sectors;
+ cnt++;
+
+ if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
+ discard_supported = true;
+ }
+ if (cnt != raid_disks) {
+ pr_warn("md/linear:%s: not enough drives present. Aborting!\n",
+ mdname(mddev));
+ goto out;
+ }
+
+ if (!discard_supported)
+ queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
+ else
+ queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue);
+
+ /*
+ * Here we calculate the device offsets.
+ */
+ conf->disks[0].end_sector = conf->disks[0].rdev->sectors;
+
+ for (i = 1; i < raid_disks; i++)
+ conf->disks[i].end_sector =
+ conf->disks[i-1].end_sector +
+ conf->disks[i].rdev->sectors;
+
+ /*
+ * conf->raid_disks is copy of mddev->raid_disks. The reason to
+ * keep a copy of mddev->raid_disks in struct linear_conf is,
+ * mddev->raid_disks may not be consistent with pointers number of
+ * conf->disks[] when it is updated in linear_add() and used to
+ * iterate old conf->disks[] earray in linear_congested().
+ * Here conf->raid_disks is always consitent with number of
+ * pointers in conf->disks[] array, and mddev->private is updated
+ * with rcu_assign_pointer() in linear_addr(), such race can be
+ * avoided.
+ */
+ conf->raid_disks = raid_disks;
+
+ return conf;
+
+out:
+ kfree(conf);
+ return NULL;
+}
+
+static int linear_run (struct mddev *mddev)
+{
+ struct linear_conf *conf;
+ int ret;
+
+ if (md_check_no_bitmap(mddev))
+ return -EINVAL;
+ conf = linear_conf(mddev, mddev->raid_disks);
+
+ if (!conf)
+ return 1;
+ mddev->private = conf;
+ md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
+
+ ret = md_integrity_register(mddev);
+ if (ret) {
+ kfree(conf);
+ mddev->private = NULL;
+ }
+ return ret;
+}
+
+static int linear_add(struct mddev *mddev, struct md_rdev *rdev)
+{
+ /* Adding a drive to a linear array allows the array to grow.
+ * It is permitted if the new drive has a matching superblock
+ * already on it, with raid_disk equal to raid_disks.
+ * It is achieved by creating a new linear_private_data structure
+ * and swapping it in in-place of the current one.
+ * The current one is never freed until the array is stopped.
+ * This avoids races.
+ */
+ struct linear_conf *newconf, *oldconf;
+
+ if (rdev->saved_raid_disk != mddev->raid_disks)
+ return -EINVAL;
+
+ rdev->raid_disk = rdev->saved_raid_disk;
+ rdev->saved_raid_disk = -1;
+
+ newconf = linear_conf(mddev,mddev->raid_disks+1);
+
+ if (!newconf)
+ return -ENOMEM;
+
+ /* newconf->raid_disks already keeps a copy of * the increased
+ * value of mddev->raid_disks, WARN_ONCE() is just used to make
+ * sure of this. It is possible that oldconf is still referenced
+ * in linear_congested(), therefore kfree_rcu() is used to free
+ * oldconf until no one uses it anymore.
+ */
+ mddev_suspend(mddev);
+ oldconf = rcu_dereference_protected(mddev->private,
+ lockdep_is_held(&mddev->reconfig_mutex));
+ mddev->raid_disks++;
+ WARN_ONCE(mddev->raid_disks != newconf->raid_disks,
+ "copied raid_disks doesn't match mddev->raid_disks");
+ rcu_assign_pointer(mddev->private, newconf);
+ md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
+ set_capacity(mddev->gendisk, mddev->array_sectors);
+ mddev_resume(mddev);
+ revalidate_disk(mddev->gendisk);
+ kfree_rcu(oldconf, rcu);
+ return 0;
+}
+
+static void linear_free(struct mddev *mddev, void *priv)
+{
+ struct linear_conf *conf = priv;
+
+ kfree(conf);
+}
+
+static bool linear_make_request(struct mddev *mddev, struct bio *bio)
+{
+ char b[BDEVNAME_SIZE];
+ struct dev_info *tmp_dev;
+ sector_t start_sector, end_sector, data_offset;
+ sector_t bio_sector = bio->bi_iter.bi_sector;
+
+ if (unlikely(bio->bi_opf & REQ_PREFLUSH)) {
+ md_flush_request(mddev, bio);
+ return true;
+ }
+
+ tmp_dev = which_dev(mddev, bio_sector);
+ start_sector = tmp_dev->end_sector - tmp_dev->rdev->sectors;
+ end_sector = tmp_dev->end_sector;
+ data_offset = tmp_dev->rdev->data_offset;
+
+ if (unlikely(bio_sector >= end_sector ||
+ bio_sector < start_sector))
+ goto out_of_bounds;
+
+ if (unlikely(bio_end_sector(bio) > end_sector)) {
+ /* This bio crosses a device boundary, so we have to split it */
+ struct bio *split = bio_split(bio, end_sector - bio_sector,
+ GFP_NOIO, mddev->bio_set);
+ bio_chain(split, bio);
+ generic_make_request(bio);
+ bio = split;
+ }
+
+ bio_set_dev(bio, tmp_dev->rdev->bdev);
+ bio->bi_iter.bi_sector = bio->bi_iter.bi_sector -
+ start_sector + data_offset;
+
+ if (unlikely((bio_op(bio) == REQ_OP_DISCARD) &&
+ !blk_queue_discard(bio->bi_disk->queue))) {
+ /* Just ignore it */
+ bio_endio(bio);
+ } else {
+ if (mddev->gendisk)
+ trace_block_bio_remap(bio->bi_disk->queue,
+ bio, disk_devt(mddev->gendisk),
+ bio_sector);
+ mddev_check_writesame(mddev, bio);
+ mddev_check_write_zeroes(mddev, bio);
+ generic_make_request(bio);
+ }
+ return true;
+
+out_of_bounds:
+ pr_err("md/linear:%s: make_request: Sector %llu out of bounds on dev %s: %llu sectors, offset %llu\n",
+ mdname(mddev),
+ (unsigned long long)bio->bi_iter.bi_sector,
+ bdevname(tmp_dev->rdev->bdev, b),
+ (unsigned long long)tmp_dev->rdev->sectors,
+ (unsigned long long)start_sector);
+ bio_io_error(bio);
+ return true;
+}
+
+static void linear_status (struct seq_file *seq, struct mddev *mddev)
+{
+ seq_printf(seq, " %dk rounding", mddev->chunk_sectors / 2);
+}
+
+static void linear_quiesce(struct mddev *mddev, int state)
+{
+}
+
+static struct md_personality linear_personality =
+{
+ .name = "linear",
+ .level = LEVEL_LINEAR,
+ .owner = THIS_MODULE,
+ .make_request = linear_make_request,
+ .run = linear_run,
+ .free = linear_free,
+ .status = linear_status,
+ .hot_add_disk = linear_add,
+ .size = linear_size,
+ .quiesce = linear_quiesce,
+ .congested = linear_congested,
+};
+
+static int __init linear_init (void)
+{
+ return register_md_personality (&linear_personality);
+}
+
+static void linear_exit (void)
+{
+ unregister_md_personality (&linear_personality);
+}
+
+module_init(linear_init);
+module_exit(linear_exit);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Linear device concatenation personality for MD");
+MODULE_ALIAS("md-personality-1"); /* LINEAR - deprecated*/
+MODULE_ALIAS("md-linear");
+MODULE_ALIAS("md-level--1");
--- /dev/null
+#ifndef _LINEAR_H
+#define _LINEAR_H
+
+struct dev_info {
+ struct md_rdev *rdev;
+ sector_t end_sector;
+};
+
+struct linear_conf
+{
+ struct rcu_head rcu;
+ sector_t array_sectors;
+ int raid_disks; /* a copy of mddev->raid_disks */
+ struct dev_info disks[0];
+};
+#endif
--- /dev/null
+/*
+ * multipath.c : Multiple Devices driver for Linux
+ *
+ * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
+ *
+ * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
+ *
+ * MULTIPATH management functions.
+ *
+ * derived from raid1.c.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * You should have received a copy of the GNU General Public License
+ * (for example /usr/src/linux/COPYING); if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/blkdev.h>
+#include <linux/module.h>
+#include <linux/raid/md_u.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include "md.h"
+#include "md-multipath.h"
+
+#define MAX_WORK_PER_DISK 128
+
+#define NR_RESERVED_BUFS 32
+
+static int multipath_map (struct mpconf *conf)
+{
+ int i, disks = conf->raid_disks;
+
+ /*
+ * Later we do read balancing on the read side
+ * now we use the first available disk.
+ */
+
+ rcu_read_lock();
+ for (i = 0; i < disks; i++) {
+ struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev);
+ if (rdev && test_bit(In_sync, &rdev->flags) &&
+ !test_bit(Faulty, &rdev->flags)) {
+ atomic_inc(&rdev->nr_pending);
+ rcu_read_unlock();
+ return i;
+ }
+ }
+ rcu_read_unlock();
+
+ pr_crit_ratelimited("multipath_map(): no more operational IO paths?\n");
+ return (-1);
+}
+
+static void multipath_reschedule_retry (struct multipath_bh *mp_bh)
+{
+ unsigned long flags;
+ struct mddev *mddev = mp_bh->mddev;
+ struct mpconf *conf = mddev->private;
+
+ spin_lock_irqsave(&conf->device_lock, flags);
+ list_add(&mp_bh->retry_list, &conf->retry_list);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+ md_wakeup_thread(mddev->thread);
+}
+
+/*
+ * multipath_end_bh_io() is called when we have finished servicing a multipathed
+ * operation and are ready to return a success/failure code to the buffer
+ * cache layer.
+ */
+static void multipath_end_bh_io(struct multipath_bh *mp_bh, blk_status_t status)
+{
+ struct bio *bio = mp_bh->master_bio;
+ struct mpconf *conf = mp_bh->mddev->private;
+
+ bio->bi_status = status;
+ bio_endio(bio);
+ mempool_free(mp_bh, conf->pool);
+}
+
+static void multipath_end_request(struct bio *bio)
+{
+ struct multipath_bh *mp_bh = bio->bi_private;
+ struct mpconf *conf = mp_bh->mddev->private;
+ struct md_rdev *rdev = conf->multipaths[mp_bh->path].rdev;
+
+ if (!bio->bi_status)
+ multipath_end_bh_io(mp_bh, 0);
+ else if (!(bio->bi_opf & REQ_RAHEAD)) {
+ /*
+ * oops, IO error:
+ */
+ char b[BDEVNAME_SIZE];
+ md_error (mp_bh->mddev, rdev);
+ pr_info("multipath: %s: rescheduling sector %llu\n",
+ bdevname(rdev->bdev,b),
+ (unsigned long long)bio->bi_iter.bi_sector);
+ multipath_reschedule_retry(mp_bh);
+ } else
+ multipath_end_bh_io(mp_bh, bio->bi_status);
+ rdev_dec_pending(rdev, conf->mddev);
+}
+
+static bool multipath_make_request(struct mddev *mddev, struct bio * bio)
+{
+ struct mpconf *conf = mddev->private;
+ struct multipath_bh * mp_bh;
+ struct multipath_info *multipath;
+
+ if (unlikely(bio->bi_opf & REQ_PREFLUSH)) {
+ md_flush_request(mddev, bio);
+ return true;
+ }
+
+ mp_bh = mempool_alloc(conf->pool, GFP_NOIO);
+
+ mp_bh->master_bio = bio;
+ mp_bh->mddev = mddev;
+
+ mp_bh->path = multipath_map(conf);
+ if (mp_bh->path < 0) {
+ bio_io_error(bio);
+ mempool_free(mp_bh, conf->pool);
+ return true;
+ }
+ multipath = conf->multipaths + mp_bh->path;
+
+ bio_init(&mp_bh->bio, NULL, 0);
+ __bio_clone_fast(&mp_bh->bio, bio);
+
+ mp_bh->bio.bi_iter.bi_sector += multipath->rdev->data_offset;
+ bio_set_dev(&mp_bh->bio, multipath->rdev->bdev);
+ mp_bh->bio.bi_opf |= REQ_FAILFAST_TRANSPORT;
+ mp_bh->bio.bi_end_io = multipath_end_request;
+ mp_bh->bio.bi_private = mp_bh;
+ mddev_check_writesame(mddev, &mp_bh->bio);
+ mddev_check_write_zeroes(mddev, &mp_bh->bio);
+ generic_make_request(&mp_bh->bio);
+ return true;
+}
+
+static void multipath_status(struct seq_file *seq, struct mddev *mddev)
+{
+ struct mpconf *conf = mddev->private;
+ int i;
+
+ seq_printf (seq, " [%d/%d] [", conf->raid_disks,
+ conf->raid_disks - mddev->degraded);
+ rcu_read_lock();
+ for (i = 0; i < conf->raid_disks; i++) {
+ struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev);
+ seq_printf (seq, "%s", rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
+ }
+ rcu_read_unlock();
+ seq_printf (seq, "]");
+}
+
+static int multipath_congested(struct mddev *mddev, int bits)
+{
+ struct mpconf *conf = mddev->private;
+ int i, ret = 0;
+
+ rcu_read_lock();
+ for (i = 0; i < mddev->raid_disks ; i++) {
+ struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev);
+ if (rdev && !test_bit(Faulty, &rdev->flags)) {
+ struct request_queue *q = bdev_get_queue(rdev->bdev);
+
+ ret |= bdi_congested(q->backing_dev_info, bits);
+ /* Just like multipath_map, we just check the
+ * first available device
+ */
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Careful, this can execute in IRQ contexts as well!
+ */
+static void multipath_error (struct mddev *mddev, struct md_rdev *rdev)
+{
+ struct mpconf *conf = mddev->private;
+ char b[BDEVNAME_SIZE];
+
+ if (conf->raid_disks - mddev->degraded <= 1) {
+ /*
+ * Uh oh, we can do nothing if this is our last path, but
+ * first check if this is a queued request for a device
+ * which has just failed.
+ */
+ pr_warn("multipath: only one IO path left and IO error.\n");
+ /* leave it active... it's all we have */
+ return;
+ }
+ /*
+ * Mark disk as unusable
+ */
+ if (test_and_clear_bit(In_sync, &rdev->flags)) {
+ unsigned long flags;
+ spin_lock_irqsave(&conf->device_lock, flags);
+ mddev->degraded++;
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+ }
+ set_bit(Faulty, &rdev->flags);
+ set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
+ pr_err("multipath: IO failure on %s, disabling IO path.\n"
+ "multipath: Operation continuing on %d IO paths.\n",
+ bdevname(rdev->bdev, b),
+ conf->raid_disks - mddev->degraded);
+}
+
+static void print_multipath_conf (struct mpconf *conf)
+{
+ int i;
+ struct multipath_info *tmp;
+
+ pr_debug("MULTIPATH conf printout:\n");
+ if (!conf) {
+ pr_debug("(conf==NULL)\n");
+ return;
+ }
+ pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
+ conf->raid_disks);
+
+ for (i = 0; i < conf->raid_disks; i++) {
+ char b[BDEVNAME_SIZE];
+ tmp = conf->multipaths + i;
+ if (tmp->rdev)
+ pr_debug(" disk%d, o:%d, dev:%s\n",
+ i,!test_bit(Faulty, &tmp->rdev->flags),
+ bdevname(tmp->rdev->bdev,b));
+ }
+}
+
+static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev)
+{
+ struct mpconf *conf = mddev->private;
+ struct request_queue *q;
+ int err = -EEXIST;
+ int path;
+ struct multipath_info *p;
+ int first = 0;
+ int last = mddev->raid_disks - 1;
+
+ if (rdev->raid_disk >= 0)
+ first = last = rdev->raid_disk;
+
+ print_multipath_conf(conf);
+
+ for (path = first; path <= last; path++)
+ if ((p=conf->multipaths+path)->rdev == NULL) {
+ q = rdev->bdev->bd_disk->queue;
+ disk_stack_limits(mddev->gendisk, rdev->bdev,
+ rdev->data_offset << 9);
+
+ err = md_integrity_add_rdev(rdev, mddev);
+ if (err)
+ break;
+ spin_lock_irq(&conf->device_lock);
+ mddev->degraded--;
+ rdev->raid_disk = path;
+ set_bit(In_sync, &rdev->flags);
+ spin_unlock_irq(&conf->device_lock);
+ rcu_assign_pointer(p->rdev, rdev);
+ err = 0;
+ break;
+ }
+
+ print_multipath_conf(conf);
+
+ return err;
+}
+
+static int multipath_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
+{
+ struct mpconf *conf = mddev->private;
+ int err = 0;
+ int number = rdev->raid_disk;
+ struct multipath_info *p = conf->multipaths + number;
+
+ print_multipath_conf(conf);
+
+ if (rdev == p->rdev) {
+ if (test_bit(In_sync, &rdev->flags) ||
+ atomic_read(&rdev->nr_pending)) {
+ pr_warn("hot-remove-disk, slot %d is identified but is still operational!\n", number);
+ err = -EBUSY;
+ goto abort;
+ }
+ p->rdev = NULL;
+ if (!test_bit(RemoveSynchronized, &rdev->flags)) {
+ synchronize_rcu();
+ if (atomic_read(&rdev->nr_pending)) {
+ /* lost the race, try later */
+ err = -EBUSY;
+ p->rdev = rdev;
+ goto abort;
+ }
+ }
+ err = md_integrity_register(mddev);
+ }
+abort:
+
+ print_multipath_conf(conf);
+ return err;
+}
+
+/*
+ * This is a kernel thread which:
+ *
+ * 1. Retries failed read operations on working multipaths.
+ * 2. Updates the raid superblock when problems encounter.
+ * 3. Performs writes following reads for array syncronising.
+ */
+
+static void multipathd(struct md_thread *thread)
+{
+ struct mddev *mddev = thread->mddev;
+ struct multipath_bh *mp_bh;
+ struct bio *bio;
+ unsigned long flags;
+ struct mpconf *conf = mddev->private;
+ struct list_head *head = &conf->retry_list;
+
+ md_check_recovery(mddev);
+ for (;;) {
+ char b[BDEVNAME_SIZE];
+ spin_lock_irqsave(&conf->device_lock, flags);
+ if (list_empty(head))
+ break;
+ mp_bh = list_entry(head->prev, struct multipath_bh, retry_list);
+ list_del(head->prev);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+
+ bio = &mp_bh->bio;
+ bio->bi_iter.bi_sector = mp_bh->master_bio->bi_iter.bi_sector;
+
+ if ((mp_bh->path = multipath_map (conf))<0) {
+ pr_err("multipath: %s: unrecoverable IO read error for block %llu\n",
+ bio_devname(bio, b),
+ (unsigned long long)bio->bi_iter.bi_sector);
+ multipath_end_bh_io(mp_bh, BLK_STS_IOERR);
+ } else {
+ pr_err("multipath: %s: redirecting sector %llu to another IO path\n",
+ bio_devname(bio, b),
+ (unsigned long long)bio->bi_iter.bi_sector);
+ *bio = *(mp_bh->master_bio);
+ bio->bi_iter.bi_sector +=
+ conf->multipaths[mp_bh->path].rdev->data_offset;
+ bio_set_dev(bio, conf->multipaths[mp_bh->path].rdev->bdev);
+ bio->bi_opf |= REQ_FAILFAST_TRANSPORT;
+ bio->bi_end_io = multipath_end_request;
+ bio->bi_private = mp_bh;
+ generic_make_request(bio);
+ }
+ }
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+}
+
+static sector_t multipath_size(struct mddev *mddev, sector_t sectors, int raid_disks)
+{
+ WARN_ONCE(sectors || raid_disks,
+ "%s does not support generic reshape\n", __func__);
+
+ return mddev->dev_sectors;
+}
+
+static int multipath_run (struct mddev *mddev)
+{
+ struct mpconf *conf;
+ int disk_idx;
+ struct multipath_info *disk;
+ struct md_rdev *rdev;
+ int working_disks;
+
+ if (md_check_no_bitmap(mddev))
+ return -EINVAL;
+
+ if (mddev->level != LEVEL_MULTIPATH) {
+ pr_warn("multipath: %s: raid level not set to multipath IO (%d)\n",
+ mdname(mddev), mddev->level);
+ goto out;
+ }
+ /*
+ * copy the already verified devices into our private MULTIPATH
+ * bookkeeping area. [whatever we allocate in multipath_run(),
+ * should be freed in multipath_free()]
+ */
+
+ conf = kzalloc(sizeof(struct mpconf), GFP_KERNEL);
+ mddev->private = conf;
+ if (!conf)
+ goto out;
+
+ conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks,
+ GFP_KERNEL);
+ if (!conf->multipaths)
+ goto out_free_conf;
+
+ working_disks = 0;
+ rdev_for_each(rdev, mddev) {
+ disk_idx = rdev->raid_disk;
+ if (disk_idx < 0 ||
+ disk_idx >= mddev->raid_disks)
+ continue;
+
+ disk = conf->multipaths + disk_idx;
+ disk->rdev = rdev;
+ disk_stack_limits(mddev->gendisk, rdev->bdev,
+ rdev->data_offset << 9);
+
+ if (!test_bit(Faulty, &rdev->flags))
+ working_disks++;
+ }
+
+ conf->raid_disks = mddev->raid_disks;
+ conf->mddev = mddev;
+ spin_lock_init(&conf->device_lock);
+ INIT_LIST_HEAD(&conf->retry_list);
+
+ if (!working_disks) {
+ pr_warn("multipath: no operational IO paths for %s\n",
+ mdname(mddev));
+ goto out_free_conf;
+ }
+ mddev->degraded = conf->raid_disks - working_disks;
+
+ conf->pool = mempool_create_kmalloc_pool(NR_RESERVED_BUFS,
+ sizeof(struct multipath_bh));
+ if (conf->pool == NULL)
+ goto out_free_conf;
+
+ mddev->thread = md_register_thread(multipathd, mddev,
+ "multipath");
+ if (!mddev->thread)
+ goto out_free_conf;
+
+ pr_info("multipath: array %s active with %d out of %d IO paths\n",
+ mdname(mddev), conf->raid_disks - mddev->degraded,
+ mddev->raid_disks);
+ /*
+ * Ok, everything is just fine now
+ */
+ md_set_array_sectors(mddev, multipath_size(mddev, 0, 0));
+
+ if (md_integrity_register(mddev))
+ goto out_free_conf;
+
+ return 0;
+
+out_free_conf:
+ mempool_destroy(conf->pool);
+ kfree(conf->multipaths);
+ kfree(conf);
+ mddev->private = NULL;
+out:
+ return -EIO;
+}
+
+static void multipath_free(struct mddev *mddev, void *priv)
+{
+ struct mpconf *conf = priv;
+
+ mempool_destroy(conf->pool);
+ kfree(conf->multipaths);
+ kfree(conf);
+}
+
+static struct md_personality multipath_personality =
+{
+ .name = "multipath",
+ .level = LEVEL_MULTIPATH,
+ .owner = THIS_MODULE,
+ .make_request = multipath_make_request,
+ .run = multipath_run,
+ .free = multipath_free,
+ .status = multipath_status,
+ .error_handler = multipath_error,
+ .hot_add_disk = multipath_add_disk,
+ .hot_remove_disk= multipath_remove_disk,
+ .size = multipath_size,
+ .congested = multipath_congested,
+};
+
+static int __init multipath_init (void)
+{
+ return register_md_personality (&multipath_personality);
+}
+
+static void __exit multipath_exit (void)
+{
+ unregister_md_personality (&multipath_personality);
+}
+
+module_init(multipath_init);
+module_exit(multipath_exit);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("simple multi-path personality for MD");
+MODULE_ALIAS("md-personality-7"); /* MULTIPATH */
+MODULE_ALIAS("md-multipath");
+MODULE_ALIAS("md-level--4");
--- /dev/null
+#ifndef _MULTIPATH_H
+#define _MULTIPATH_H
+
+struct multipath_info {
+ struct md_rdev *rdev;
+};
+
+struct mpconf {
+ struct mddev *mddev;
+ struct multipath_info *multipaths;
+ int raid_disks;
+ spinlock_t device_lock;
+ struct list_head retry_list;
+
+ mempool_t *pool;
+};
+
+/*
+ * this is our 'private' 'collective' MULTIPATH buffer head.
+ * it contains information about what kind of IO operations were started
+ * for this MULTIPATH operation, and about their status:
+ */
+
+struct multipath_bh {
+ struct mddev *mddev;
+ struct bio *master_bio;
+ struct bio bio;
+ int path;
+ struct list_head retry_list;
+};
+#endif
#include <trace/events/block.h>
#include "md.h"
-#include "bitmap.h"
+#include "md-bitmap.h"
#include "md-cluster.h"
#ifndef MODULE
+++ /dev/null
-/*
- * multipath.c : Multiple Devices driver for Linux
- *
- * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
- *
- * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
- *
- * MULTIPATH management functions.
- *
- * derived from raid1.c.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * You should have received a copy of the GNU General Public License
- * (for example /usr/src/linux/COPYING); if not, write to the Free
- * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <linux/blkdev.h>
-#include <linux/module.h>
-#include <linux/raid/md_u.h>
-#include <linux/seq_file.h>
-#include <linux/slab.h>
-#include "md.h"
-#include "multipath.h"
-
-#define MAX_WORK_PER_DISK 128
-
-#define NR_RESERVED_BUFS 32
-
-static int multipath_map (struct mpconf *conf)
-{
- int i, disks = conf->raid_disks;
-
- /*
- * Later we do read balancing on the read side
- * now we use the first available disk.
- */
-
- rcu_read_lock();
- for (i = 0; i < disks; i++) {
- struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev);
- if (rdev && test_bit(In_sync, &rdev->flags) &&
- !test_bit(Faulty, &rdev->flags)) {
- atomic_inc(&rdev->nr_pending);
- rcu_read_unlock();
- return i;
- }
- }
- rcu_read_unlock();
-
- pr_crit_ratelimited("multipath_map(): no more operational IO paths?\n");
- return (-1);
-}
-
-static void multipath_reschedule_retry (struct multipath_bh *mp_bh)
-{
- unsigned long flags;
- struct mddev *mddev = mp_bh->mddev;
- struct mpconf *conf = mddev->private;
-
- spin_lock_irqsave(&conf->device_lock, flags);
- list_add(&mp_bh->retry_list, &conf->retry_list);
- spin_unlock_irqrestore(&conf->device_lock, flags);
- md_wakeup_thread(mddev->thread);
-}
-
-/*
- * multipath_end_bh_io() is called when we have finished servicing a multipathed
- * operation and are ready to return a success/failure code to the buffer
- * cache layer.
- */
-static void multipath_end_bh_io(struct multipath_bh *mp_bh, blk_status_t status)
-{
- struct bio *bio = mp_bh->master_bio;
- struct mpconf *conf = mp_bh->mddev->private;
-
- bio->bi_status = status;
- bio_endio(bio);
- mempool_free(mp_bh, conf->pool);
-}
-
-static void multipath_end_request(struct bio *bio)
-{
- struct multipath_bh *mp_bh = bio->bi_private;
- struct mpconf *conf = mp_bh->mddev->private;
- struct md_rdev *rdev = conf->multipaths[mp_bh->path].rdev;
-
- if (!bio->bi_status)
- multipath_end_bh_io(mp_bh, 0);
- else if (!(bio->bi_opf & REQ_RAHEAD)) {
- /*
- * oops, IO error:
- */
- char b[BDEVNAME_SIZE];
- md_error (mp_bh->mddev, rdev);
- pr_info("multipath: %s: rescheduling sector %llu\n",
- bdevname(rdev->bdev,b),
- (unsigned long long)bio->bi_iter.bi_sector);
- multipath_reschedule_retry(mp_bh);
- } else
- multipath_end_bh_io(mp_bh, bio->bi_status);
- rdev_dec_pending(rdev, conf->mddev);
-}
-
-static bool multipath_make_request(struct mddev *mddev, struct bio * bio)
-{
- struct mpconf *conf = mddev->private;
- struct multipath_bh * mp_bh;
- struct multipath_info *multipath;
-
- if (unlikely(bio->bi_opf & REQ_PREFLUSH)) {
- md_flush_request(mddev, bio);
- return true;
- }
-
- mp_bh = mempool_alloc(conf->pool, GFP_NOIO);
-
- mp_bh->master_bio = bio;
- mp_bh->mddev = mddev;
-
- mp_bh->path = multipath_map(conf);
- if (mp_bh->path < 0) {
- bio_io_error(bio);
- mempool_free(mp_bh, conf->pool);
- return true;
- }
- multipath = conf->multipaths + mp_bh->path;
-
- bio_init(&mp_bh->bio, NULL, 0);
- __bio_clone_fast(&mp_bh->bio, bio);
-
- mp_bh->bio.bi_iter.bi_sector += multipath->rdev->data_offset;
- bio_set_dev(&mp_bh->bio, multipath->rdev->bdev);
- mp_bh->bio.bi_opf |= REQ_FAILFAST_TRANSPORT;
- mp_bh->bio.bi_end_io = multipath_end_request;
- mp_bh->bio.bi_private = mp_bh;
- mddev_check_writesame(mddev, &mp_bh->bio);
- mddev_check_write_zeroes(mddev, &mp_bh->bio);
- generic_make_request(&mp_bh->bio);
- return true;
-}
-
-static void multipath_status(struct seq_file *seq, struct mddev *mddev)
-{
- struct mpconf *conf = mddev->private;
- int i;
-
- seq_printf (seq, " [%d/%d] [", conf->raid_disks,
- conf->raid_disks - mddev->degraded);
- rcu_read_lock();
- for (i = 0; i < conf->raid_disks; i++) {
- struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev);
- seq_printf (seq, "%s", rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
- }
- rcu_read_unlock();
- seq_printf (seq, "]");
-}
-
-static int multipath_congested(struct mddev *mddev, int bits)
-{
- struct mpconf *conf = mddev->private;
- int i, ret = 0;
-
- rcu_read_lock();
- for (i = 0; i < mddev->raid_disks ; i++) {
- struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev);
- if (rdev && !test_bit(Faulty, &rdev->flags)) {
- struct request_queue *q = bdev_get_queue(rdev->bdev);
-
- ret |= bdi_congested(q->backing_dev_info, bits);
- /* Just like multipath_map, we just check the
- * first available device
- */
- break;
- }
- }
- rcu_read_unlock();
- return ret;
-}
-
-/*
- * Careful, this can execute in IRQ contexts as well!
- */
-static void multipath_error (struct mddev *mddev, struct md_rdev *rdev)
-{
- struct mpconf *conf = mddev->private;
- char b[BDEVNAME_SIZE];
-
- if (conf->raid_disks - mddev->degraded <= 1) {
- /*
- * Uh oh, we can do nothing if this is our last path, but
- * first check if this is a queued request for a device
- * which has just failed.
- */
- pr_warn("multipath: only one IO path left and IO error.\n");
- /* leave it active... it's all we have */
- return;
- }
- /*
- * Mark disk as unusable
- */
- if (test_and_clear_bit(In_sync, &rdev->flags)) {
- unsigned long flags;
- spin_lock_irqsave(&conf->device_lock, flags);
- mddev->degraded++;
- spin_unlock_irqrestore(&conf->device_lock, flags);
- }
- set_bit(Faulty, &rdev->flags);
- set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
- pr_err("multipath: IO failure on %s, disabling IO path.\n"
- "multipath: Operation continuing on %d IO paths.\n",
- bdevname(rdev->bdev, b),
- conf->raid_disks - mddev->degraded);
-}
-
-static void print_multipath_conf (struct mpconf *conf)
-{
- int i;
- struct multipath_info *tmp;
-
- pr_debug("MULTIPATH conf printout:\n");
- if (!conf) {
- pr_debug("(conf==NULL)\n");
- return;
- }
- pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
- conf->raid_disks);
-
- for (i = 0; i < conf->raid_disks; i++) {
- char b[BDEVNAME_SIZE];
- tmp = conf->multipaths + i;
- if (tmp->rdev)
- pr_debug(" disk%d, o:%d, dev:%s\n",
- i,!test_bit(Faulty, &tmp->rdev->flags),
- bdevname(tmp->rdev->bdev,b));
- }
-}
-
-static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev)
-{
- struct mpconf *conf = mddev->private;
- struct request_queue *q;
- int err = -EEXIST;
- int path;
- struct multipath_info *p;
- int first = 0;
- int last = mddev->raid_disks - 1;
-
- if (rdev->raid_disk >= 0)
- first = last = rdev->raid_disk;
-
- print_multipath_conf(conf);
-
- for (path = first; path <= last; path++)
- if ((p=conf->multipaths+path)->rdev == NULL) {
- q = rdev->bdev->bd_disk->queue;
- disk_stack_limits(mddev->gendisk, rdev->bdev,
- rdev->data_offset << 9);
-
- err = md_integrity_add_rdev(rdev, mddev);
- if (err)
- break;
- spin_lock_irq(&conf->device_lock);
- mddev->degraded--;
- rdev->raid_disk = path;
- set_bit(In_sync, &rdev->flags);
- spin_unlock_irq(&conf->device_lock);
- rcu_assign_pointer(p->rdev, rdev);
- err = 0;
- break;
- }
-
- print_multipath_conf(conf);
-
- return err;
-}
-
-static int multipath_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
-{
- struct mpconf *conf = mddev->private;
- int err = 0;
- int number = rdev->raid_disk;
- struct multipath_info *p = conf->multipaths + number;
-
- print_multipath_conf(conf);
-
- if (rdev == p->rdev) {
- if (test_bit(In_sync, &rdev->flags) ||
- atomic_read(&rdev->nr_pending)) {
- pr_warn("hot-remove-disk, slot %d is identified but is still operational!\n", number);
- err = -EBUSY;
- goto abort;
- }
- p->rdev = NULL;
- if (!test_bit(RemoveSynchronized, &rdev->flags)) {
- synchronize_rcu();
- if (atomic_read(&rdev->nr_pending)) {
- /* lost the race, try later */
- err = -EBUSY;
- p->rdev = rdev;
- goto abort;
- }
- }
- err = md_integrity_register(mddev);
- }
-abort:
-
- print_multipath_conf(conf);
- return err;
-}
-
-/*
- * This is a kernel thread which:
- *
- * 1. Retries failed read operations on working multipaths.
- * 2. Updates the raid superblock when problems encounter.
- * 3. Performs writes following reads for array syncronising.
- */
-
-static void multipathd(struct md_thread *thread)
-{
- struct mddev *mddev = thread->mddev;
- struct multipath_bh *mp_bh;
- struct bio *bio;
- unsigned long flags;
- struct mpconf *conf = mddev->private;
- struct list_head *head = &conf->retry_list;
-
- md_check_recovery(mddev);
- for (;;) {
- char b[BDEVNAME_SIZE];
- spin_lock_irqsave(&conf->device_lock, flags);
- if (list_empty(head))
- break;
- mp_bh = list_entry(head->prev, struct multipath_bh, retry_list);
- list_del(head->prev);
- spin_unlock_irqrestore(&conf->device_lock, flags);
-
- bio = &mp_bh->bio;
- bio->bi_iter.bi_sector = mp_bh->master_bio->bi_iter.bi_sector;
-
- if ((mp_bh->path = multipath_map (conf))<0) {
- pr_err("multipath: %s: unrecoverable IO read error for block %llu\n",
- bio_devname(bio, b),
- (unsigned long long)bio->bi_iter.bi_sector);
- multipath_end_bh_io(mp_bh, BLK_STS_IOERR);
- } else {
- pr_err("multipath: %s: redirecting sector %llu to another IO path\n",
- bio_devname(bio, b),
- (unsigned long long)bio->bi_iter.bi_sector);
- *bio = *(mp_bh->master_bio);
- bio->bi_iter.bi_sector +=
- conf->multipaths[mp_bh->path].rdev->data_offset;
- bio_set_dev(bio, conf->multipaths[mp_bh->path].rdev->bdev);
- bio->bi_opf |= REQ_FAILFAST_TRANSPORT;
- bio->bi_end_io = multipath_end_request;
- bio->bi_private = mp_bh;
- generic_make_request(bio);
- }
- }
- spin_unlock_irqrestore(&conf->device_lock, flags);
-}
-
-static sector_t multipath_size(struct mddev *mddev, sector_t sectors, int raid_disks)
-{
- WARN_ONCE(sectors || raid_disks,
- "%s does not support generic reshape\n", __func__);
-
- return mddev->dev_sectors;
-}
-
-static int multipath_run (struct mddev *mddev)
-{
- struct mpconf *conf;
- int disk_idx;
- struct multipath_info *disk;
- struct md_rdev *rdev;
- int working_disks;
-
- if (md_check_no_bitmap(mddev))
- return -EINVAL;
-
- if (mddev->level != LEVEL_MULTIPATH) {
- pr_warn("multipath: %s: raid level not set to multipath IO (%d)\n",
- mdname(mddev), mddev->level);
- goto out;
- }
- /*
- * copy the already verified devices into our private MULTIPATH
- * bookkeeping area. [whatever we allocate in multipath_run(),
- * should be freed in multipath_free()]
- */
-
- conf = kzalloc(sizeof(struct mpconf), GFP_KERNEL);
- mddev->private = conf;
- if (!conf)
- goto out;
-
- conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks,
- GFP_KERNEL);
- if (!conf->multipaths)
- goto out_free_conf;
-
- working_disks = 0;
- rdev_for_each(rdev, mddev) {
- disk_idx = rdev->raid_disk;
- if (disk_idx < 0 ||
- disk_idx >= mddev->raid_disks)
- continue;
-
- disk = conf->multipaths + disk_idx;
- disk->rdev = rdev;
- disk_stack_limits(mddev->gendisk, rdev->bdev,
- rdev->data_offset << 9);
-
- if (!test_bit(Faulty, &rdev->flags))
- working_disks++;
- }
-
- conf->raid_disks = mddev->raid_disks;
- conf->mddev = mddev;
- spin_lock_init(&conf->device_lock);
- INIT_LIST_HEAD(&conf->retry_list);
-
- if (!working_disks) {
- pr_warn("multipath: no operational IO paths for %s\n",
- mdname(mddev));
- goto out_free_conf;
- }
- mddev->degraded = conf->raid_disks - working_disks;
-
- conf->pool = mempool_create_kmalloc_pool(NR_RESERVED_BUFS,
- sizeof(struct multipath_bh));
- if (conf->pool == NULL)
- goto out_free_conf;
-
- mddev->thread = md_register_thread(multipathd, mddev,
- "multipath");
- if (!mddev->thread)
- goto out_free_conf;
-
- pr_info("multipath: array %s active with %d out of %d IO paths\n",
- mdname(mddev), conf->raid_disks - mddev->degraded,
- mddev->raid_disks);
- /*
- * Ok, everything is just fine now
- */
- md_set_array_sectors(mddev, multipath_size(mddev, 0, 0));
-
- if (md_integrity_register(mddev))
- goto out_free_conf;
-
- return 0;
-
-out_free_conf:
- mempool_destroy(conf->pool);
- kfree(conf->multipaths);
- kfree(conf);
- mddev->private = NULL;
-out:
- return -EIO;
-}
-
-static void multipath_free(struct mddev *mddev, void *priv)
-{
- struct mpconf *conf = priv;
-
- mempool_destroy(conf->pool);
- kfree(conf->multipaths);
- kfree(conf);
-}
-
-static struct md_personality multipath_personality =
-{
- .name = "multipath",
- .level = LEVEL_MULTIPATH,
- .owner = THIS_MODULE,
- .make_request = multipath_make_request,
- .run = multipath_run,
- .free = multipath_free,
- .status = multipath_status,
- .error_handler = multipath_error,
- .hot_add_disk = multipath_add_disk,
- .hot_remove_disk= multipath_remove_disk,
- .size = multipath_size,
- .congested = multipath_congested,
-};
-
-static int __init multipath_init (void)
-{
- return register_md_personality (&multipath_personality);
-}
-
-static void __exit multipath_exit (void)
-{
- unregister_md_personality (&multipath_personality);
-}
-
-module_init(multipath_init);
-module_exit(multipath_exit);
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("simple multi-path personality for MD");
-MODULE_ALIAS("md-personality-7"); /* MULTIPATH */
-MODULE_ALIAS("md-multipath");
-MODULE_ALIAS("md-level--4");
+++ /dev/null
-#ifndef _MULTIPATH_H
-#define _MULTIPATH_H
-
-struct multipath_info {
- struct md_rdev *rdev;
-};
-
-struct mpconf {
- struct mddev *mddev;
- struct multipath_info *multipaths;
- int raid_disks;
- spinlock_t device_lock;
- struct list_head retry_list;
-
- mempool_t *pool;
-};
-
-/*
- * this is our 'private' 'collective' MULTIPATH buffer head.
- * it contains information about what kind of IO operations were started
- * for this MULTIPATH operation, and about their status:
- */
-
-struct multipath_bh {
- struct mddev *mddev;
- struct bio *master_bio;
- struct bio bio;
- int path;
- struct list_head retry_list;
-};
-#endif
#include "md.h"
#include "raid1.h"
-#include "bitmap.h"
+#include "md-bitmap.h"
#define UNSUPPORTED_MDDEV_FLAGS \
((1L << MD_HAS_JOURNAL) | \
#include "md.h"
#include "raid10.h"
#include "raid0.h"
-#include "bitmap.h"
+#include "md-bitmap.h"
/*
* RAID10 provides a combination of RAID0 and RAID1 functionality.
#include <linux/types.h>
#include "md.h"
#include "raid5.h"
-#include "bitmap.h"
+#include "md-bitmap.h"
#include "raid5-log.h"
/*
#include "md.h"
#include "raid5.h"
#include "raid0.h"
-#include "bitmap.h"
+#include "md-bitmap.h"
#include "raid5-log.h"
#define UNSUPPORTED_MDDEV_FLAGS (1L << MD_FAILFAST_SUPPORTED)
projects / linux-2.6-block.git / commitdiff