switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_mapping->a_ops = &btrfs_aops;
+ extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
+ inode->i_mapping, GFP_NOFS);
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
break;
BTRFS_I(inode)->block_group->key.objectid);
}
-static int btrfs_update_inode(struct btrfs_trans_handle *trans,
+int btrfs_update_inode(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct inode *inode)
{
int found_extent;
int del_item;
+ btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
path = btrfs_alloc_path();
path->reada = -1;
BUG_ON(!path);
return ret;
}
+static int btrfs_cow_one_page(struct btrfs_trans_handle *trans,
+ struct inode *inode, struct page *page,
+ size_t zero_start)
+{
+ char *kaddr;
+ int ret = 0;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ u64 alloc_hint = 0;
+ u64 page_start = page->index << PAGE_CACHE_SHIFT;
+ struct btrfs_key ins;
+
+ if (!PagePrivate(page)) {
+ SetPagePrivate(page);
+ set_page_private(page, 1);
+ page_cache_get(page);
+ }
+
+ btrfs_set_trans_block_group(trans, inode);
+
+ ret = btrfs_drop_extents(trans, root, inode,
+ page_start, page_start + PAGE_CACHE_SIZE,
+ &alloc_hint);
+ if (ret)
+ goto out;
+ ret = btrfs_alloc_extent(trans, root, inode->i_ino, 1, 0,
+ alloc_hint, (u64)-1, &ins, 1);
+ if (ret)
+ goto out;
+ ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
+ page_start, ins.objectid, 1, 1);
+ if (ret)
+ goto out;
+ SetPageChecked(page);
+ kaddr = kmap(page);
+ if (zero_start != PAGE_CACHE_SIZE) {
+ memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
+ flush_dcache_page(page);
+ }
+ kunmap(page);
+
+out:
+ return ret;
+}
+
/*
* taken from block_truncate_page, but does cow as it zeros out
* any bytes left in the last page in the file.
static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
{
struct inode *inode = mapping->host;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
unsigned blocksize = 1 << inode->i_blkbits;
pgoff_t index = from >> PAGE_CACHE_SHIFT;
unsigned offset = from & (PAGE_CACHE_SIZE-1);
struct page *page;
- char *kaddr;
int ret = 0;
- struct btrfs_root *root = BTRFS_I(inode)->root;
- u64 alloc_hint = 0;
- struct btrfs_key ins;
- struct btrfs_trans_handle *trans;
+ u64 page_start;
if ((offset & (blocksize - 1)) == 0)
goto out;
page = grab_cache_page(mapping, index);
if (!page)
goto out;
-
if (!PageUptodate(page)) {
ret = btrfs_readpage(NULL, page);
lock_page(page);
goto out;
}
}
+ page_start = page->index << PAGE_CACHE_SHIFT;
+
mutex_lock(&root->fs_info->fs_mutex);
trans = btrfs_start_transaction(root, 1);
- btrfs_set_trans_block_group(trans, inode);
-
- ret = btrfs_drop_extents(trans, root, inode,
- page->index << PAGE_CACHE_SHIFT,
- (page->index + 1) << PAGE_CACHE_SHIFT,
- &alloc_hint);
- if (ret)
- goto out;
- ret = btrfs_alloc_extent(trans, root, inode->i_ino, 1, 0,
- alloc_hint, (u64)-1, &ins, 1);
- if (ret)
- goto out;
- ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
- page->index << PAGE_CACHE_SHIFT,
- ins.objectid, 1, 1);
- if (ret)
- goto out;
- SetPageChecked(page);
- kaddr = kmap(page);
- memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
- flush_dcache_page(page);
- ret = btrfs_csum_file_block(trans, root, inode->i_ino,
- page->index << PAGE_CACHE_SHIFT,
- kaddr, PAGE_CACHE_SIZE);
- kunmap(page);
+ ret = btrfs_cow_one_page(trans, inode, page, offset);
+ if (!ret) {
+ char *kaddr = kmap(page);
+ ret = btrfs_csum_file_block(trans, root, inode->i_ino,
+ page_start, kaddr, PAGE_CACHE_SIZE);
+ kunmap(page);
+ }
+ set_extent_dirty(&BTRFS_I(inode)->extent_tree,
+ page_start, page_start + PAGE_CACHE_SIZE - 1,
+ GFP_NOFS);
+ set_page_dirty(page);
btrfs_end_transaction(trans, root);
mutex_unlock(&root->fs_info->fs_mutex);
- set_page_dirty(page);
unlock_page(page);
page_cache_release(page);
out:
inode->i_mapping->a_ops = &btrfs_aops;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
+ extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
+ inode->i_mapping, GFP_NOFS);
}
dir->i_sb->s_dirt = 1;
btrfs_update_inode_block_group(trans, inode);
return err;
}
+struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
+ size_t page_offset, u64 start, u64 end,
+ int create)
+{
+ int ret;
+ int err = 0;
+ u64 blocknr;
+ u64 extent_start = 0;
+ u64 extent_end = 0;
+ u64 objectid = inode->i_ino;
+ u32 found_type;
+ int failed_insert = 0;
+ struct btrfs_path *path;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_file_extent_item *item;
+ struct btrfs_leaf *leaf;
+ struct btrfs_disk_key *found_key;
+ struct extent_map *em = NULL;
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ struct btrfs_trans_handle *trans = NULL;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ mutex_lock(&root->fs_info->fs_mutex);
+
+again:
+ em = lookup_extent_mapping(em_tree, start, end);
+ if (em) {
+ goto out;
+ }
+ if (!em) {
+ em = alloc_extent_map(GFP_NOFS);
+ if (!em) {
+ err = -ENOMEM;
+ goto out;
+ }
+ em->start = 0;
+ em->end = 0;
+ }
+ em->bdev = inode->i_sb->s_bdev;
+ ret = btrfs_lookup_file_extent(NULL, root, path,
+ objectid, start, 0);
+ if (ret < 0) {
+ err = ret;
+ goto out;
+ }
+
+ if (ret != 0) {
+ if (path->slots[0] == 0)
+ goto not_found;
+ path->slots[0]--;
+ }
+
+ item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
+ struct btrfs_file_extent_item);
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ blocknr = btrfs_file_extent_disk_blocknr(item);
+ blocknr += btrfs_file_extent_offset(item);
+
+ /* are we inside the extent that was found? */
+ found_key = &leaf->items[path->slots[0]].key;
+ found_type = btrfs_disk_key_type(found_key);
+ if (btrfs_disk_key_objectid(found_key) != objectid ||
+ found_type != BTRFS_EXTENT_DATA_KEY) {
+ goto not_found;
+ }
+
+ found_type = btrfs_file_extent_type(item);
+ extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
+ if (found_type == BTRFS_FILE_EXTENT_REG) {
+ extent_end = extent_start +
+ (btrfs_file_extent_num_blocks(item) << inode->i_blkbits);
+ err = 0;
+ if (start < extent_start || start > extent_end) {
+ em->start = start;
+ if (start < extent_start) {
+ em->end = extent_end - 1;
+ } else {
+ em->end = end;
+ }
+ goto not_found_em;
+ }
+ if (btrfs_file_extent_disk_blocknr(item) == 0) {
+ em->start = extent_start;
+ em->end = extent_end - 1;
+ em->block_start = 0;
+ em->block_end = 0;
+ goto insert;
+ }
+ em->block_start = blocknr << inode->i_blkbits;
+ em->block_end = em->block_start +
+ (btrfs_file_extent_num_blocks(item) <<
+ inode->i_blkbits) - 1;
+ em->start = extent_start;
+ em->end = extent_end - 1;
+ goto insert;
+ } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
+ char *ptr;
+ char *map;
+ u32 size;
+
+ size = btrfs_file_extent_inline_len(leaf->items +
+ path->slots[0]);
+ extent_end = extent_start + size;
+ if (start < extent_start || start > extent_end) {
+ em->start = start;
+ if (start < extent_start) {
+ em->end = extent_end - 1;
+ } else {
+ em->end = end;
+ }
+ goto not_found_em;
+ }
+ em->block_start = EXTENT_MAP_INLINE;
+ em->block_end = EXTENT_MAP_INLINE;
+ em->start = extent_start;
+ em->end = extent_end - 1;
+ if (!page) {
+ goto insert;
+ }
+ ptr = btrfs_file_extent_inline_start(item);
+ map = kmap(page);
+ memcpy(map + page_offset, ptr, size);
+ flush_dcache_page(result->b_page);
+ kunmap(page);
+ set_extent_uptodate(em_tree, extent_start,
+ extent_end, GFP_NOFS);
+ goto insert;
+ } else {
+ printk("unkknown found_type %d\n", found_type);
+ WARN_ON(1);
+ }
+not_found:
+ em->start = start;
+ em->end = end;
+not_found_em:
+ em->block_start = 0;
+ em->block_end = 0;
+insert:
+ btrfs_release_path(root, path);
+ if (em->start > start || em->end < start) {
+ printk("bad extent! %Lu %Lu start %Lu end %Lu\n", em->start, em->end, start, end);
+ WARN_ON(1);
+ err = -EIO;
+ goto out;
+ }
+ ret = add_extent_mapping(em_tree, em);
+ if (ret == -EEXIST) {
+ free_extent_map(em);
+ failed_insert++;
+ if (failed_insert > 5) {
+ printk("failing to insert %Lu %Lu\n", start, end);
+ err = -EIO;
+ goto out;
+ }
+ em = NULL;
+ goto again;
+ }
+ err = 0;
+out:
+ btrfs_free_path(path);
+ if (trans) {
+ ret = btrfs_end_transaction(trans, root);
+ if (!err)
+ err = ret;
+ }
+ mutex_unlock(&root->fs_info->fs_mutex);
+ if (err) {
+ free_extent_map(em);
+ WARN_ON(1);
+ return ERR_PTR(err);
+ }
+ return em;
+}
+
+
/*
* FIBMAP and others want to pass in a fake buffer head. They need to
* use BTRFS_GET_BLOCK_NO_DIRECT to make sure we don't try to memcpy
return err;
}
-static int btrfs_get_block_csum(struct inode *inode, sector_t iblock,
- struct buffer_head *result, int create)
-{
- int ret;
- struct btrfs_root *root = BTRFS_I(inode)->root;
- struct page *page = result->b_page;
- u64 offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(result);
- struct btrfs_csum_item *item;
- struct btrfs_path *path = NULL;
-
- mutex_lock(&root->fs_info->fs_mutex);
- ret = btrfs_get_block_lock(inode, iblock, result, create);
- if (ret)
- goto out;
-
- path = btrfs_alloc_path();
- item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, offset, 0);
- if (IS_ERR(item)) {
- ret = PTR_ERR(item);
- /* a csum that isn't present is a preallocated region. */
- if (ret == -ENOENT || ret == -EFBIG)
- ret = 0;
- result->b_private = NULL;
- goto out;
- }
- memcpy((char *)&result->b_private, &item->csum, BTRFS_CRC32_SIZE);
-out:
- if (path)
- btrfs_free_path(path);
- mutex_unlock(&root->fs_info->fs_mutex);
- return ret;
-}
-
static int btrfs_get_block_bmap(struct inode *inode, sector_t iblock,
struct buffer_head *result, int create)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
- mutex_lock(&root->fs_info->fs_mutex);
- btrfs_get_block_lock(inode, iblock, result, BTRFS_GET_BLOCK_NO_DIRECT);
- mutex_unlock(&root->fs_info->fs_mutex);
+ u64 start = iblock << inode->i_blkbits;
+ u64 end = start + root->blocksize -1;
+ struct extent_map *em;
+
+ em = btrfs_get_extent(inode, NULL, 0, start, end, 0);
+ if (em && !IS_ERR(em) && em->block_start != EXTENT_MAP_INLINE &&
+ em->block_start != 0) {
+ u64 offset;
+ offset = start - em->start;
+ start = (em->block_start + offset) >> inode->i_blkbits;
+ btrfs_map_bh_to_logical(root, result, start);
+ }
return 0;
}
static int btrfs_prepare_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
- return block_prepare_write(page, from, to, btrfs_get_block);
+ return extent_prepare_write(&BTRFS_I(page->mapping->host)->extent_tree,
+ page->mapping->host, page, from, to,
+ btrfs_get_extent);
}
-static void buffer_io_error(struct buffer_head *bh)
+int btrfs_readpage(struct file *file, struct page *page)
{
- char b[BDEVNAME_SIZE];
-
- printk(KERN_ERR "Buffer I/O error on device %s, logical block %Lu\n",
- bdevname(bh->b_bdev, b),
- (unsigned long long)bh->b_blocknr);
+ struct extent_map_tree *tree;
+ tree = &BTRFS_I(page->mapping->host)->extent_tree;
+ return extent_read_full_page(tree, page, btrfs_get_extent);
}
-
-/*
- * I/O completion handler for block_read_full_page() - pages
- * which come unlocked at the end of I/O.
- */
-static void btrfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
+static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
{
- unsigned long flags;
- struct buffer_head *first;
- struct buffer_head *tmp;
- struct page *page;
- int page_uptodate = 1;
- struct inode *inode;
- int ret;
-
- BUG_ON(!buffer_async_read(bh));
-
- page = bh->b_page;
- inode = page->mapping->host;
- if (uptodate) {
- void *kaddr;
- struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
- if (bh->b_private) {
- char csum[BTRFS_CRC32_SIZE];
- kaddr = kmap_atomic(page, KM_IRQ0);
- ret = btrfs_csum_data(root, kaddr + bh_offset(bh),
- bh->b_size, csum);
- BUG_ON(ret);
- if (memcmp(csum, &bh->b_private, BTRFS_CRC32_SIZE)) {
- u64 offset;
- offset = (page->index << PAGE_CACHE_SHIFT) +
- bh_offset(bh);
- printk("btrfs csum failed ino %lu off %llu\n",
- page->mapping->host->i_ino,
- (unsigned long long)offset);
- memset(kaddr + bh_offset(bh), 1, bh->b_size);
- flush_dcache_page(page);
- }
- kunmap_atomic(kaddr, KM_IRQ0);
- }
- set_buffer_uptodate(bh);
- } else {
- clear_buffer_uptodate(bh);
- if (printk_ratelimit())
- buffer_io_error(bh);
- SetPageError(page);
- }
-
- /*
- * Be _very_ careful from here on. Bad things can happen if
- * two buffer heads end IO at almost the same time and both
- * decide that the page is now completely done.
- */
- first = page_buffers(page);
- local_irq_save(flags);
- bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
- clear_buffer_async_read(bh);
- unlock_buffer(bh);
- tmp = bh;
- do {
- if (!buffer_uptodate(tmp))
- page_uptodate = 0;
- if (buffer_async_read(tmp)) {
- BUG_ON(!buffer_locked(tmp));
- goto still_busy;
- }
- tmp = tmp->b_this_page;
- } while (tmp != bh);
- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
- local_irq_restore(flags);
-
- /*
- * If none of the buffers had errors and they are all
- * uptodate then we can set the page uptodate.
- */
- if (page_uptodate && !PageError(page))
- SetPageUptodate(page);
- unlock_page(page);
- return;
-
-still_busy:
- bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
- local_irq_restore(flags);
- return;
+ struct extent_map_tree *tree;
+ tree = &BTRFS_I(page->mapping->host)->extent_tree;
+ return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
}
-/*
- * Generic "read page" function for block devices that have the normal
- * get_block functionality. This is most of the block device filesystems.
- * Reads the page asynchronously --- the unlock_buffer() and
- * set/clear_buffer_uptodate() functions propagate buffer state into the
- * page struct once IO has completed.
- */
-int btrfs_readpage(struct file *file, struct page *page)
+static int btrfs_releasepage(struct page *page, gfp_t unused_gfp_flags)
{
- struct inode *inode = page->mapping->host;
- sector_t iblock, lblock;
- struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
- unsigned int blocksize;
- int nr, i;
- int fully_mapped = 1;
-
- BUG_ON(!PageLocked(page));
- blocksize = 1 << inode->i_blkbits;
- if (!page_has_buffers(page))
- create_empty_buffers(page, blocksize, 0);
- head = page_buffers(page);
-
- iblock = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
- lblock = (i_size_read(inode)+blocksize-1) >> inode->i_blkbits;
- bh = head;
- nr = 0;
- i = 0;
-
- do {
- if (buffer_uptodate(bh))
- continue;
-
- if (!buffer_mapped(bh)) {
- int err = 0;
-
- fully_mapped = 0;
- if (iblock < lblock) {
- WARN_ON(bh->b_size != blocksize);
- err = btrfs_get_block_csum(inode, iblock,
- bh, 0);
- if (err)
- SetPageError(page);
- }
- if (!buffer_mapped(bh)) {
- void *kaddr = kmap_atomic(page, KM_USER0);
- memset(kaddr + i * blocksize, 0, blocksize);
- flush_dcache_page(page);
- kunmap_atomic(kaddr, KM_USER0);
- if (!err)
- set_buffer_uptodate(bh);
- continue;
- }
- /*
- * get_block() might have updated the buffer
- * synchronously
- */
- if (buffer_uptodate(bh))
- continue;
- }
- arr[nr++] = bh;
- } while (i++, iblock++, (bh = bh->b_this_page) != head);
-
- if (fully_mapped)
- SetPageMappedToDisk(page);
-
- if (!nr) {
- /*
- * All buffers are uptodate - we can set the page uptodate
- * as well. But not if get_block() returned an error.
- */
- if (!PageError(page))
- SetPageUptodate(page);
- unlock_page(page);
- return 0;
- }
-
- /* Stage two: lock the buffers */
- for (i = 0; i < nr; i++) {
- bh = arr[i];
- lock_buffer(bh);
- bh->b_end_io = btrfs_end_buffer_async_read;
- set_buffer_async_read(bh);
- }
-
- /*
- * Stage 3: start the IO. Check for uptodateness
- * inside the buffer lock in case another process reading
- * the underlying blockdev brought it uptodate (the sct fix).
- */
- for (i = 0; i < nr; i++) {
- bh = arr[i];
- if (buffer_uptodate(bh))
- btrfs_end_buffer_async_read(bh, 1);
- else
- submit_bh(READ, bh);
- }
- return 0;
-}
-
-/*
- * Aside from a tiny bit of packed file data handling, this is the
- * same as the generic code.
- *
- * While block_write_full_page is writing back the dirty buffers under
- * the page lock, whoever dirtied the buffers may decide to clean them
- * again at any time. We handle that by only looking at the buffer
- * state inside lock_buffer().
- *
- * If block_write_full_page() is called for regular writeback
- * (wbc->sync_mode == WB_SYNC_NONE) then it will redirty a page which has a
- * locked buffer. This only can happen if someone has written the buffer
- * directly, with submit_bh(). At the address_space level PageWriteback
- * prevents this contention from occurring.
- */
-static int __btrfs_write_full_page(struct inode *inode, struct page *page,
- struct writeback_control *wbc)
-{
- int err;
- sector_t block;
- sector_t last_block;
- struct buffer_head *bh, *head;
- const unsigned blocksize = 1 << inode->i_blkbits;
- int nr_underway = 0;
- struct btrfs_root *root = BTRFS_I(inode)->root;
-
- BUG_ON(!PageLocked(page));
-
- last_block = (i_size_read(inode) - 1) >> inode->i_blkbits;
-
- /* no csumming allowed when from PF_MEMALLOC */
- if (current->flags & PF_MEMALLOC) {
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- return 0;
- }
+ struct extent_map_tree *tree;
+ int ret;
- if (!page_has_buffers(page)) {
- create_empty_buffers(page, blocksize,
- (1 << BH_Dirty)|(1 << BH_Uptodate));
+ if (page->private != 1) {
+ WARN_ON(1);
+ return try_to_free_buffers(page);
}
-
- /*
- * Be very careful. We have no exclusion from __set_page_dirty_buffers
- * here, and the (potentially unmapped) buffers may become dirty at
- * any time. If a buffer becomes dirty here after we've inspected it
- * then we just miss that fact, and the page stays dirty.
- *
- * Buffers outside i_size may be dirtied by __set_page_dirty_buffers;
- * handle that here by just cleaning them.
- */
-
- block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
- head = page_buffers(page);
- bh = head;
-
- /*
- * Get all the dirty buffers mapped to disk addresses and
- * handle any aliases from the underlying blockdev's mapping.
- */
- do {
- if (block > last_block) {
- /*
- * mapped buffers outside i_size will occur, because
- * this page can be outside i_size when there is a
- * truncate in progress.
- */
- /*
- * The buffer was zeroed by block_write_full_page()
- */
- clear_buffer_dirty(bh);
- set_buffer_uptodate(bh);
- } else if (!buffer_mapped(bh) && buffer_dirty(bh)) {
- WARN_ON(bh->b_size != blocksize);
- err = btrfs_get_block(inode, block, bh, 0);
- if (err) {
- goto recover;
- }
- if (buffer_new(bh)) {
- /* blockdev mappings never come here */
- clear_buffer_new(bh);
- }
- }
- bh = bh->b_this_page;
- block++;
- } while (bh != head);
-
- do {
- if (!buffer_mapped(bh))
- continue;
- /*
- * If it's a fully non-blocking write attempt and we cannot
- * lock the buffer then redirty the page. Note that this can
- * potentially cause a busy-wait loop from pdflush and kswapd
- * activity, but those code paths have their own higher-level
- * throttling.
- */
- if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
- lock_buffer(bh);
- } else if (test_set_buffer_locked(bh)) {
- redirty_page_for_writepage(wbc, page);
- continue;
- }
- if (test_clear_buffer_dirty(bh) && bh->b_blocknr != 0) {
- struct btrfs_trans_handle *trans;
- int ret;
- u64 off = page->index << PAGE_CACHE_SHIFT;
- char *kaddr;
-
- off += bh_offset(bh);
- mutex_lock(&root->fs_info->fs_mutex);
- trans = btrfs_start_transaction(root, 1);
- btrfs_set_trans_block_group(trans, inode);
- kaddr = kmap(page);
- btrfs_csum_file_block(trans, root, inode->i_ino,
- off, kaddr + bh_offset(bh),
- bh->b_size);
- kunmap(page);
- ret = btrfs_end_transaction(trans, root);
- BUG_ON(ret);
- mutex_unlock(&root->fs_info->fs_mutex);
- mark_buffer_async_write(bh);
- } else {
- unlock_buffer(bh);
- }
- } while ((bh = bh->b_this_page) != head);
-
- /*
- * The page and its buffers are protected by PageWriteback(), so we can
- * drop the bh refcounts early.
- */
- BUG_ON(PageWriteback(page));
- set_page_writeback(page);
-
- do {
- struct buffer_head *next = bh->b_this_page;
- if (buffer_async_write(bh)) {
- submit_bh(WRITE, bh);
- nr_underway++;
- }
- bh = next;
- } while (bh != head);
- unlock_page(page);
-
- err = 0;
-done:
- if (nr_underway == 0) {
- /*
- * The page was marked dirty, but the buffers were
- * clean. Someone wrote them back by hand with
- * ll_rw_block/submit_bh. A rare case.
- */
- int uptodate = 1;
- do {
- if (!buffer_uptodate(bh)) {
- uptodate = 0;
- break;
- }
- bh = bh->b_this_page;
- } while (bh != head);
- if (uptodate)
- SetPageUptodate(page);
- end_page_writeback(page);
+ tree = &BTRFS_I(page->mapping->host)->extent_tree;
+ ret = try_release_extent_mapping(tree, page);
+ if (ret == 1) {
+ ClearPagePrivate(page);
+ set_page_private(page, 0);
+ page_cache_release(page);
}
- return err;
-
-recover:
- /*
- * ENOSPC, or some other error. We may already have added some
- * blocks to the file, so we need to write these out to avoid
- * exposing stale data.
- * The page is currently locked and not marked for writeback
- */
- bh = head;
- /* Recovery: lock and submit the mapped buffers */
- do {
- if (buffer_mapped(bh) && buffer_dirty(bh)) {
- lock_buffer(bh);
- mark_buffer_async_write(bh);
- } else {
- /*
- * The buffer may have been set dirty during
- * attachment to a dirty page.
- */
- clear_buffer_dirty(bh);
- }
- } while ((bh = bh->b_this_page) != head);
- SetPageError(page);
- BUG_ON(PageWriteback(page));
- set_page_writeback(page);
- do {
- struct buffer_head *next = bh->b_this_page;
- if (buffer_async_write(bh)) {
- clear_buffer_dirty(bh);
- submit_bh(WRITE, bh);
- nr_underway++;
- }
- bh = next;
- } while (bh != head);
- unlock_page(page);
- goto done;
+ return ret;
}
-static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
+static void btrfs_invalidatepage(struct page *page, unsigned long offset)
{
- struct inode * const inode = page->mapping->host;
- loff_t i_size = i_size_read(inode);
- const pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
- unsigned offset;
- void *kaddr;
-
- /* Is the page fully inside i_size? */
- if (page->index < end_index)
- return __btrfs_write_full_page(inode, page, wbc);
-
- /* Is the page fully outside i_size? (truncate in progress) */
- offset = i_size & (PAGE_CACHE_SIZE-1);
- if (page->index >= end_index+1 || !offset) {
- /*
- * The page may have dirty, unmapped buffers. For example,
- * they may have been added in ext3_writepage(). Make them
- * freeable here, so the page does not leak.
- */
- block_invalidatepage(page, 0);
- unlock_page(page);
- return 0; /* don't care */
- }
+ struct extent_map_tree *tree;
- /*
- * The page straddles i_size. It must be zeroed out on each and every
- * writepage invokation because it may be mmapped. "A file is mapped
- * in multiples of the page size. For a file that is not a multiple of
- * the page size, the remaining memory is zeroed when mapped, and
- * writes to that region are not written out to the file."
- */
- kaddr = kmap_atomic(page, KM_USER0);
- memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
- flush_dcache_page(page);
- kunmap_atomic(kaddr, KM_USER0);
- return __btrfs_write_full_page(inode, page, wbc);
+ tree = &BTRFS_I(page->mapping->host)->extent_tree;
+ extent_invalidatepage(tree, page, offset);
+ btrfs_releasepage(page, GFP_NOFS);
}
/*
int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
{
struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
unsigned long end;
loff_t size;
int ret = -EINVAL;
+ u64 page_start;
lock_page(page);
wait_on_page_writeback(page);
size = i_size_read(inode);
+ page_start = page->index << PAGE_CACHE_SHIFT;
+
if ((page->mapping != inode->i_mapping) ||
- ((page->index << PAGE_CACHE_SHIFT) > size)) {
+ (page_start > size)) {
/* page got truncated out from underneath us */
goto out_unlock;
}
/* page is wholly or partially inside EOF */
- if (((page->index + 1) << PAGE_CACHE_SHIFT) > size)
+ if (page_start + PAGE_CACHE_SIZE > size)
end = size & ~PAGE_CACHE_MASK;
else
end = PAGE_CACHE_SIZE;
- ret = btrfs_prepare_write(NULL, page, 0, end);
- if (!ret)
- ret = btrfs_commit_write(NULL, page, 0, end);
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ ret = btrfs_cow_one_page(trans, inode, page, end);
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ set_extent_dirty(&BTRFS_I(inode)->extent_tree,
+ page_start, page_start + PAGE_CACHE_SIZE - 1,
+ GFP_NOFS);
+ set_page_dirty(page);
out_unlock:
unlock_page(page);
int btrfs_commit_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
- struct inode *inode = page->mapping->host;
- struct buffer_head *bh;
- loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
-
- SetPageUptodate(page);
- bh = page_buffers(page);
- set_buffer_uptodate(bh);
- if (buffer_mapped(bh) && bh->b_blocknr != 0) {
- set_page_dirty(page);
- }
- if (pos > inode->i_size) {
- i_size_write(inode, pos);
- mark_inode_dirty(inode);
- }
- return 0;
+ return extent_commit_write(&BTRFS_I(page->mapping->host)->extent_tree,
+ page->mapping->host, page, from, to);
}
static int create_subvol(struct btrfs_root *root, char *name, int namelen)
inode->i_mapping->a_ops = &btrfs_aops;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
+ extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
+ inode->i_mapping, GFP_NOFS);
}
dir->i_sb->s_dirt = 1;
btrfs_update_inode_block_group(trans, inode);
.prepare_write = btrfs_prepare_write,
.commit_write = btrfs_commit_write,
.bmap = btrfs_bmap,
+ .invalidatepage = btrfs_invalidatepage,
+ .releasepage = btrfs_releasepage,
+ .set_page_dirty = __set_page_dirty_nobuffers,
};
static struct address_space_operations btrfs_symlink_aops = {
projects / linux-2.6-block.git / blobdiff