* Copyright (C) 2013 Shaohua Li <shli@kernel.org>
* Copyright (C) 2014 Red Hat, Inc.
* Copyright (C) 2015 Arrikto, Inc.
+ * Copyright (C) 2017 Chinamobile, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
#include <linux/parser.h>
#include <linux/vmalloc.h>
#include <linux/uio_driver.h>
+#include <linux/radix-tree.h>
#include <linux/stringify.h>
#include <linux/bitops.h>
#include <linux/highmem.h>
#include <linux/configfs.h>
+#include <linux/mutex.h>
+#include <linux/kthread.h>
#include <net/genetlink.h>
#include <scsi/scsi_common.h>
#include <scsi/scsi_proto.h>
* this may have a 'UAM' comment.
*/
-
#define TCMU_TIME_OUT (30 * MSEC_PER_SEC)
-#define DATA_BLOCK_BITS 256
-#define DATA_BLOCK_SIZE 4096
+/* For cmd area, the size is fixed 8MB */
+#define CMDR_SIZE (8 * 1024 * 1024)
-#define CMDR_SIZE (16 * 4096)
+/*
+ * For data area, the block size is PAGE_SIZE and
+ * the total size is 256K * PAGE_SIZE.
+ */
+#define DATA_BLOCK_SIZE PAGE_SIZE
+#define DATA_BLOCK_BITS (256 * 1024)
#define DATA_SIZE (DATA_BLOCK_BITS * DATA_BLOCK_SIZE)
+#define DATA_BLOCK_INIT_BITS 128
+/* The total size of the ring is 8M + 256K * PAGE_SIZE */
#define TCMU_RING_SIZE (CMDR_SIZE + DATA_SIZE)
+/* Default maximum of the global data blocks(512K * PAGE_SIZE) */
+#define TCMU_GLOBAL_MAX_BLOCKS (512 * 1024)
+
static struct device *tcmu_root_device;
struct tcmu_hba {
#define TCMU_CONFIG_LEN 256
struct tcmu_dev {
+ struct list_head node;
+
struct se_device se_dev;
char *name;
struct uio_info uio_info;
+ struct inode *inode;
+
struct tcmu_mailbox *mb_addr;
size_t dev_size;
u32 cmdr_size;
size_t data_off;
size_t data_size;
- DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS);
-
wait_queue_head_t wait_cmdr;
- /* TODO should this be a mutex? */
- spinlock_t cmdr_lock;
+ struct mutex cmdr_lock;
+
+ bool waiting_global;
+ uint32_t dbi_max;
+ uint32_t dbi_thresh;
+ DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS);
+ struct radix_tree_root data_blocks;
struct idr commands;
spinlock_t commands_lock;
/* Can't use se_cmd when cleaning up expired cmds, because if
cmd has been completed then accessing se_cmd is off limits */
- DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS);
+ uint32_t dbi_cnt;
+ uint32_t dbi_cur;
+ uint32_t *dbi;
unsigned long deadline;
unsigned long flags;
};
+static struct task_struct *unmap_thread;
+static wait_queue_head_t unmap_wait;
+static DEFINE_MUTEX(root_udev_mutex);
+static LIST_HEAD(root_udev);
+
+static atomic_t global_db_count = ATOMIC_INIT(0);
+
static struct kmem_cache *tcmu_cmd_cache;
/* multicast group */
.netnsok = true,
};
+#define tcmu_cmd_set_dbi_cur(cmd, index) ((cmd)->dbi_cur = (index))
+#define tcmu_cmd_reset_dbi_cur(cmd) tcmu_cmd_set_dbi_cur(cmd, 0)
+#define tcmu_cmd_set_dbi(cmd, index) ((cmd)->dbi[(cmd)->dbi_cur++] = (index))
+#define tcmu_cmd_get_dbi(cmd) ((cmd)->dbi[(cmd)->dbi_cur++])
+
+static void tcmu_cmd_free_data(struct tcmu_cmd *tcmu_cmd, uint32_t len)
+{
+ struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
+ uint32_t i;
+
+ for (i = 0; i < len; i++)
+ clear_bit(tcmu_cmd->dbi[i], udev->data_bitmap);
+}
+
+static inline bool tcmu_get_empty_block(struct tcmu_dev *udev,
+ struct tcmu_cmd *tcmu_cmd)
+{
+ struct page *page;
+ int ret, dbi;
+
+ dbi = find_first_zero_bit(udev->data_bitmap, udev->dbi_thresh);
+ if (dbi == udev->dbi_thresh)
+ return false;
+
+ page = radix_tree_lookup(&udev->data_blocks, dbi);
+ if (!page) {
+
+ if (atomic_add_return(1, &global_db_count) >
+ TCMU_GLOBAL_MAX_BLOCKS) {
+ atomic_dec(&global_db_count);
+ return false;
+ }
+
+ /* try to get new page from the mm */
+ page = alloc_page(GFP_KERNEL);
+ if (!page)
+ return false;
+
+ ret = radix_tree_insert(&udev->data_blocks, dbi, page);
+ if (ret) {
+ __free_page(page);
+ return false;
+ }
+
+ }
+
+ if (dbi > udev->dbi_max)
+ udev->dbi_max = dbi;
+
+ set_bit(dbi, udev->data_bitmap);
+ tcmu_cmd_set_dbi(tcmu_cmd, dbi);
+
+ return true;
+}
+
+static bool tcmu_get_empty_blocks(struct tcmu_dev *udev,
+ struct tcmu_cmd *tcmu_cmd)
+{
+ int i;
+
+ udev->waiting_global = false;
+
+ for (i = tcmu_cmd->dbi_cur; i < tcmu_cmd->dbi_cnt; i++) {
+ if (!tcmu_get_empty_block(udev, tcmu_cmd))
+ goto err;
+ }
+ return true;
+
+err:
+ udev->waiting_global = true;
+ /* Try to wake up the unmap thread */
+ wake_up(&unmap_wait);
+ return false;
+}
+
+static inline struct page *
+tcmu_get_block_page(struct tcmu_dev *udev, uint32_t dbi)
+{
+ return radix_tree_lookup(&udev->data_blocks, dbi);
+}
+
+static inline void tcmu_free_cmd(struct tcmu_cmd *tcmu_cmd)
+{
+ kfree(tcmu_cmd->dbi);
+ kmem_cache_free(tcmu_cmd_cache, tcmu_cmd);
+}
+
+static inline size_t tcmu_cmd_get_data_length(struct tcmu_cmd *tcmu_cmd)
+{
+ struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
+ size_t data_length = round_up(se_cmd->data_length, DATA_BLOCK_SIZE);
+
+ if (se_cmd->se_cmd_flags & SCF_BIDI) {
+ BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents));
+ data_length += round_up(se_cmd->t_bidi_data_sg->length,
+ DATA_BLOCK_SIZE);
+ }
+
+ return data_length;
+}
+
+static inline uint32_t tcmu_cmd_get_block_cnt(struct tcmu_cmd *tcmu_cmd)
+{
+ size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
+
+ return data_length / DATA_BLOCK_SIZE;
+}
+
static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd)
{
struct se_device *se_dev = se_cmd->se_dev;
tcmu_cmd->deadline = jiffies +
msecs_to_jiffies(udev->cmd_time_out);
+ tcmu_cmd_reset_dbi_cur(tcmu_cmd);
+ tcmu_cmd->dbi_cnt = tcmu_cmd_get_block_cnt(tcmu_cmd);
+ tcmu_cmd->dbi = kcalloc(tcmu_cmd->dbi_cnt, sizeof(uint32_t),
+ GFP_KERNEL);
+ if (!tcmu_cmd->dbi) {
+ kmem_cache_free(tcmu_cmd_cache, tcmu_cmd);
+ return NULL;
+ }
+
idr_preload(GFP_KERNEL);
spin_lock_irq(&udev->commands_lock);
cmd_id = idr_alloc(&udev->commands, tcmu_cmd, 0,
idr_preload_end();
if (cmd_id < 0) {
- kmem_cache_free(tcmu_cmd_cache, tcmu_cmd);
+ tcmu_free_cmd(tcmu_cmd);
return NULL;
}
tcmu_cmd->cmd_id = cmd_id;
#define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size)
/* offset is relative to mb_addr */
-static inline size_t get_block_offset(struct tcmu_dev *dev,
- int block, int remaining)
+static inline size_t get_block_offset_user(struct tcmu_dev *dev,
+ int dbi, int remaining)
{
- return dev->data_off + block * DATA_BLOCK_SIZE +
+ return dev->data_off + dbi * DATA_BLOCK_SIZE +
DATA_BLOCK_SIZE - remaining;
}
return (size_t)iov->iov_base + iov->iov_len;
}
-static void alloc_and_scatter_data_area(struct tcmu_dev *udev,
- struct scatterlist *data_sg, unsigned int data_nents,
- struct iovec **iov, int *iov_cnt, bool copy_data)
+static int scatter_data_area(struct tcmu_dev *udev,
+ struct tcmu_cmd *tcmu_cmd, struct scatterlist *data_sg,
+ unsigned int data_nents, struct iovec **iov,
+ int *iov_cnt, bool copy_data)
{
- int i, block;
+ int i, dbi;
int block_remaining = 0;
- void *from, *to;
- size_t copy_bytes, to_offset;
+ void *from, *to = NULL;
+ size_t copy_bytes, to_offset, offset;
struct scatterlist *sg;
+ struct page *page;
for_each_sg(data_sg, sg, data_nents, i) {
int sg_remaining = sg->length;
from = kmap_atomic(sg_page(sg)) + sg->offset;
while (sg_remaining > 0) {
if (block_remaining == 0) {
- block = find_first_zero_bit(udev->data_bitmap,
- DATA_BLOCK_BITS);
+ if (to)
+ kunmap_atomic(to);
+
block_remaining = DATA_BLOCK_SIZE;
- set_bit(block, udev->data_bitmap);
+ dbi = tcmu_cmd_get_dbi(tcmu_cmd);
+ page = tcmu_get_block_page(udev, dbi);
+ to = kmap_atomic(page);
}
+
copy_bytes = min_t(size_t, sg_remaining,
block_remaining);
- to_offset = get_block_offset(udev, block,
+ to_offset = get_block_offset_user(udev, dbi,
block_remaining);
- to = (void *)udev->mb_addr + to_offset;
+ offset = DATA_BLOCK_SIZE - block_remaining;
+ to = (void *)(unsigned long)to + offset;
+
if (*iov_cnt != 0 &&
to_offset == iov_tail(udev, *iov)) {
(*iov)->iov_len += copy_bytes;
} else {
new_iov(iov, iov_cnt, udev);
- (*iov)->iov_base = (void __user *) to_offset;
+ (*iov)->iov_base = (void __user *)to_offset;
(*iov)->iov_len = copy_bytes;
}
if (copy_data) {
}
kunmap_atomic(from - sg->offset);
}
-}
+ if (to)
+ kunmap_atomic(to);
-static void free_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd)
-{
- bitmap_xor(udev->data_bitmap, udev->data_bitmap, cmd->data_bitmap,
- DATA_BLOCK_BITS);
+ return 0;
}
static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
bool bidi)
{
struct se_cmd *se_cmd = cmd->se_cmd;
- int i, block;
+ int i, dbi;
int block_remaining = 0;
- void *from, *to;
- size_t copy_bytes, from_offset;
+ void *from = NULL, *to;
+ size_t copy_bytes, offset;
struct scatterlist *sg, *data_sg;
+ struct page *page;
unsigned int data_nents;
- DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS);
-
- bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS);
+ uint32_t count = 0;
if (!bidi) {
data_sg = se_cmd->t_data_sg;
data_nents = se_cmd->t_data_nents;
} else {
- uint32_t count;
/*
* For bidi case, the first count blocks are for Data-Out
* the Data-Out buffer blocks should be discarded.
*/
count = DIV_ROUND_UP(se_cmd->data_length, DATA_BLOCK_SIZE);
- while (count--) {
- block = find_first_bit(bitmap, DATA_BLOCK_BITS);
- clear_bit(block, bitmap);
- }
data_sg = se_cmd->t_bidi_data_sg;
data_nents = se_cmd->t_bidi_data_nents;
}
+ tcmu_cmd_set_dbi_cur(cmd, count);
+
for_each_sg(data_sg, sg, data_nents, i) {
int sg_remaining = sg->length;
to = kmap_atomic(sg_page(sg)) + sg->offset;
while (sg_remaining > 0) {
if (block_remaining == 0) {
- block = find_first_bit(bitmap,
- DATA_BLOCK_BITS);
+ if (from)
+ kunmap_atomic(from);
+
block_remaining = DATA_BLOCK_SIZE;
- clear_bit(block, bitmap);
+ dbi = tcmu_cmd_get_dbi(cmd);
+ page = tcmu_get_block_page(udev, dbi);
+ from = kmap_atomic(page);
}
copy_bytes = min_t(size_t, sg_remaining,
block_remaining);
- from_offset = get_block_offset(udev, block,
- block_remaining);
- from = (void *) udev->mb_addr + from_offset;
+ offset = DATA_BLOCK_SIZE - block_remaining;
+ from = (void *)(unsigned long)from + offset;
tcmu_flush_dcache_range(from, copy_bytes);
memcpy(to + sg->length - sg_remaining, from,
copy_bytes);
}
kunmap_atomic(to - sg->offset);
}
+ if (from)
+ kunmap_atomic(from);
}
-static inline size_t spc_bitmap_free(unsigned long *bitmap)
+static inline size_t spc_bitmap_free(unsigned long *bitmap, uint32_t thresh)
{
- return DATA_BLOCK_SIZE * (DATA_BLOCK_BITS -
- bitmap_weight(bitmap, DATA_BLOCK_BITS));
+ return DATA_BLOCK_SIZE * (thresh - bitmap_weight(bitmap, thresh));
}
/*
*
* Called with ring lock held.
*/
-static bool is_ring_space_avail(struct tcmu_dev *udev, size_t cmd_size, size_t data_needed)
+static bool is_ring_space_avail(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
+ size_t cmd_size, size_t data_needed)
{
struct tcmu_mailbox *mb = udev->mb_addr;
+ uint32_t blocks_needed = (data_needed + DATA_BLOCK_SIZE - 1)
+ / DATA_BLOCK_SIZE;
size_t space, cmd_needed;
u32 cmd_head;
return false;
}
- space = spc_bitmap_free(udev->data_bitmap);
+ /* try to check and get the data blocks as needed */
+ space = spc_bitmap_free(udev->data_bitmap, udev->dbi_thresh);
if (space < data_needed) {
- pr_debug("no data space: only %zu available, but ask for %zu\n",
- space, data_needed);
- return false;
+ unsigned long blocks_left = DATA_BLOCK_BITS - udev->dbi_thresh;
+ unsigned long grow;
+
+ if (blocks_left < blocks_needed) {
+ pr_debug("no data space: only %lu available, but ask for %zu\n",
+ blocks_left * DATA_BLOCK_SIZE,
+ data_needed);
+ return false;
+ }
+
+ /* Try to expand the thresh */
+ if (!udev->dbi_thresh) {
+ /* From idle state */
+ uint32_t init_thresh = DATA_BLOCK_INIT_BITS;
+
+ udev->dbi_thresh = max(blocks_needed, init_thresh);
+ } else {
+ /*
+ * Grow the data area by max(blocks needed,
+ * dbi_thresh / 2), but limited to the max
+ * DATA_BLOCK_BITS size.
+ */
+ grow = max(blocks_needed, udev->dbi_thresh / 2);
+ udev->dbi_thresh += grow;
+ if (udev->dbi_thresh > DATA_BLOCK_BITS)
+ udev->dbi_thresh = DATA_BLOCK_BITS;
+ }
}
+ if (!tcmu_get_empty_blocks(udev, cmd))
+ return false;
+
return true;
}
-static inline size_t tcmu_cmd_get_data_length(struct tcmu_cmd *tcmu_cmd)
+static inline size_t tcmu_cmd_get_base_cmd_size(size_t iov_cnt)
{
- struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
- size_t data_length = round_up(se_cmd->data_length, DATA_BLOCK_SIZE);
-
- if (se_cmd->se_cmd_flags & SCF_BIDI) {
- BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents));
- data_length += round_up(se_cmd->t_bidi_data_sg->length,
- DATA_BLOCK_SIZE);
- }
-
- return data_length;
+ return max(offsetof(struct tcmu_cmd_entry, req.iov[iov_cnt]),
+ sizeof(struct tcmu_cmd_entry));
}
-static inline uint32_t tcmu_cmd_get_block_cnt(struct tcmu_cmd *tcmu_cmd)
+static inline size_t tcmu_cmd_get_cmd_size(struct tcmu_cmd *tcmu_cmd,
+ size_t base_command_size)
{
- size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
+ struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
+ size_t command_size;
- return data_length / DATA_BLOCK_SIZE;
+ command_size = base_command_size +
+ round_up(scsi_command_size(se_cmd->t_task_cdb),
+ TCMU_OP_ALIGN_SIZE);
+
+ WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1));
+
+ return command_size;
}
static sense_reason_t
struct tcmu_mailbox *mb;
struct tcmu_cmd_entry *entry;
struct iovec *iov;
- int iov_cnt;
+ int iov_cnt, ret;
uint32_t cmd_head;
uint64_t cdb_off;
bool copy_to_data_area;
size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
- DECLARE_BITMAP(old_bitmap, DATA_BLOCK_BITS);
if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags))
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
* Must be a certain minimum size for response sense info, but
* also may be larger if the iov array is large.
*
- * We prepare way too many iovs for potential uses here, because it's
- * expensive to tell how many regions are freed in the bitmap
- */
- base_command_size = max(offsetof(struct tcmu_cmd_entry,
- req.iov[tcmu_cmd_get_block_cnt(tcmu_cmd)]),
- sizeof(struct tcmu_cmd_entry));
- command_size = base_command_size
- + round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE);
-
- WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1));
+ * We prepare as many iovs as possbile for potential uses here,
+ * because it's expensive to tell how many regions are freed in
+ * the bitmap & global data pool, as the size calculated here
+ * will only be used to do the checks.
+ *
+ * The size will be recalculated later as actually needed to save
+ * cmd area memories.
+ */
+ base_command_size = tcmu_cmd_get_base_cmd_size(tcmu_cmd->dbi_cnt);
+ command_size = tcmu_cmd_get_cmd_size(tcmu_cmd, base_command_size);
- spin_lock_irq(&udev->cmdr_lock);
+ mutex_lock(&udev->cmdr_lock);
mb = udev->mb_addr;
cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */
pr_warn("TCMU: Request of size %zu/%zu is too big for %u/%zu "
"cmd ring/data area\n", command_size, data_length,
udev->cmdr_size, udev->data_size);
- spin_unlock_irq(&udev->cmdr_lock);
+ mutex_unlock(&udev->cmdr_lock);
return TCM_INVALID_CDB_FIELD;
}
- while (!is_ring_space_avail(udev, command_size, data_length)) {
+ while (!is_ring_space_avail(udev, tcmu_cmd, command_size, data_length)) {
int ret;
DEFINE_WAIT(__wait);
prepare_to_wait(&udev->wait_cmdr, &__wait, TASK_INTERRUPTIBLE);
pr_debug("sleeping for ring space\n");
- spin_unlock_irq(&udev->cmdr_lock);
+ mutex_unlock(&udev->cmdr_lock);
if (udev->cmd_time_out)
ret = schedule_timeout(
msecs_to_jiffies(udev->cmd_time_out));
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
- spin_lock_irq(&udev->cmdr_lock);
+ mutex_lock(&udev->cmdr_lock);
/* We dropped cmdr_lock, cmd_head is stale */
cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */
entry = (void *) mb + CMDR_OFF + cmd_head;
tcmu_flush_dcache_range(entry, sizeof(*entry));
tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD);
- tcmu_hdr_set_len(&entry->hdr.len_op, command_size);
entry->hdr.cmd_id = tcmu_cmd->cmd_id;
entry->hdr.kflags = 0;
entry->hdr.uflags = 0;
- bitmap_copy(old_bitmap, udev->data_bitmap, DATA_BLOCK_BITS);
-
/* Handle allocating space from the data area */
+ tcmu_cmd_reset_dbi_cur(tcmu_cmd);
iov = &entry->req.iov[0];
iov_cnt = 0;
copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE
|| se_cmd->se_cmd_flags & SCF_BIDI);
- alloc_and_scatter_data_area(udev, se_cmd->t_data_sg,
- se_cmd->t_data_nents, &iov, &iov_cnt, copy_to_data_area);
+ ret = scatter_data_area(udev, tcmu_cmd, se_cmd->t_data_sg,
+ se_cmd->t_data_nents, &iov, &iov_cnt,
+ copy_to_data_area);
+ if (ret) {
+ tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cnt);
+ mutex_unlock(&udev->cmdr_lock);
+
+ pr_err("tcmu: alloc and scatter data failed\n");
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
entry->req.iov_cnt = iov_cnt;
entry->req.iov_dif_cnt = 0;
if (se_cmd->se_cmd_flags & SCF_BIDI) {
iov_cnt = 0;
iov++;
- alloc_and_scatter_data_area(udev, se_cmd->t_bidi_data_sg,
- se_cmd->t_bidi_data_nents, &iov, &iov_cnt,
- false);
+ ret = scatter_data_area(udev, tcmu_cmd,
+ se_cmd->t_bidi_data_sg,
+ se_cmd->t_bidi_data_nents,
+ &iov, &iov_cnt, false);
+ if (ret) {
+ tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cnt);
+ mutex_unlock(&udev->cmdr_lock);
+
+ pr_err("tcmu: alloc and scatter bidi data failed\n");
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
entry->req.iov_bidi_cnt = iov_cnt;
}
- /* cmd's data_bitmap is what changed in process */
- bitmap_xor(tcmu_cmd->data_bitmap, old_bitmap, udev->data_bitmap,
- DATA_BLOCK_BITS);
+
+ /*
+ * Recalaulate the command's base size and size according
+ * to the actual needs
+ */
+ base_command_size = tcmu_cmd_get_base_cmd_size(entry->req.iov_cnt +
+ entry->req.iov_bidi_cnt);
+ command_size = tcmu_cmd_get_cmd_size(tcmu_cmd, base_command_size);
+
+ tcmu_hdr_set_len(&entry->hdr.len_op, command_size);
/* All offsets relative to mb_addr, not start of entry! */
cdb_off = CMDR_OFF + cmd_head + base_command_size;
UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size);
tcmu_flush_dcache_range(mb, sizeof(*mb));
-
- spin_unlock_irq(&udev->cmdr_lock);
+ mutex_unlock(&udev->cmdr_lock);
/* TODO: only if FLUSH and FUA? */
uio_event_notify(&udev->uio_info);
idr_remove(&udev->commands, tcmu_cmd->cmd_id);
spin_unlock_irq(&udev->commands_lock);
- kmem_cache_free(tcmu_cmd_cache, tcmu_cmd);
+ tcmu_free_cmd(tcmu_cmd);
}
return ret;
struct se_cmd *se_cmd = cmd->se_cmd;
struct tcmu_dev *udev = cmd->tcmu_dev;
- if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) {
- /*
- * cmd has been completed already from timeout, just reclaim
- * data area space and free cmd
- */
- free_data_area(udev, cmd);
+ /*
+ * cmd has been completed already from timeout, just reclaim
+ * data area space and free cmd
+ */
+ if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags))
+ goto out;
- kmem_cache_free(tcmu_cmd_cache, cmd);
- return;
- }
+ tcmu_cmd_reset_dbi_cur(cmd);
if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) {
- free_data_area(udev, cmd);
pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n",
cmd->se_cmd);
entry->rsp.scsi_status = SAM_STAT_CHECK_CONDITION;
} else if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) {
memcpy(se_cmd->sense_buffer, entry->rsp.sense_buffer,
se_cmd->scsi_sense_length);
- free_data_area(udev, cmd);
} else if (se_cmd->se_cmd_flags & SCF_BIDI) {
/* Get Data-In buffer before clean up */
gather_data_area(udev, cmd, true);
- free_data_area(udev, cmd);
} else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
gather_data_area(udev, cmd, false);
- free_data_area(udev, cmd);
} else if (se_cmd->data_direction == DMA_TO_DEVICE) {
- free_data_area(udev, cmd);
+ /* TODO: */
} else if (se_cmd->data_direction != DMA_NONE) {
pr_warn("TCMU: data direction was %d!\n",
se_cmd->data_direction);
}
target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status);
- cmd->se_cmd = NULL;
- kmem_cache_free(tcmu_cmd_cache, cmd);
+out:
+ cmd->se_cmd = NULL;
+ tcmu_cmd_free_data(cmd, cmd->dbi_cnt);
+ tcmu_free_cmd(cmd);
}
static unsigned int tcmu_handle_completions(struct tcmu_dev *udev)
{
struct tcmu_mailbox *mb;
- unsigned long flags;
int handled = 0;
if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) {
return 0;
}
- spin_lock_irqsave(&udev->cmdr_lock, flags);
-
mb = udev->mb_addr;
tcmu_flush_dcache_range(mb, sizeof(*mb));
if (mb->cmd_tail == mb->cmd_head)
del_timer(&udev->timeout); /* no more pending cmds */
- spin_unlock_irqrestore(&udev->cmdr_lock, flags);
-
wake_up(&udev->wait_cmdr);
return handled;
{
struct tcmu_dev *udev = (struct tcmu_dev *)data;
unsigned long flags;
- int handled;
-
- handled = tcmu_handle_completions(udev);
-
- pr_warn("%d completions handled from timeout\n", handled);
spin_lock_irqsave(&udev->commands_lock, flags);
idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL);
spin_unlock_irqrestore(&udev->commands_lock, flags);
+ /* Try to wake up the ummap thread */
+ wake_up(&unmap_wait);
+
/*
* We don't need to wakeup threads on wait_cmdr since they have their
* own timeout.
udev->cmd_time_out = TCMU_TIME_OUT;
init_waitqueue_head(&udev->wait_cmdr);
- spin_lock_init(&udev->cmdr_lock);
+ mutex_init(&udev->cmdr_lock);
idr_init(&udev->commands);
spin_lock_init(&udev->commands_lock);
{
struct tcmu_dev *tcmu_dev = container_of(info, struct tcmu_dev, uio_info);
+ mutex_lock(&tcmu_dev->cmdr_lock);
tcmu_handle_completions(tcmu_dev);
+ mutex_unlock(&tcmu_dev->cmdr_lock);
return 0;
}
return -1;
}
+static struct page *tcmu_try_get_block_page(struct tcmu_dev *udev, uint32_t dbi)
+{
+ struct page *page;
+ int ret;
+
+ mutex_lock(&udev->cmdr_lock);
+ page = tcmu_get_block_page(udev, dbi);
+ if (likely(page)) {
+ mutex_unlock(&udev->cmdr_lock);
+ return page;
+ }
+
+ /*
+ * Normally it shouldn't be here:
+ * Only when the userspace has touched the blocks which
+ * are out of the tcmu_cmd's data iov[], and will return
+ * one zeroed page.
+ */
+ pr_warn("Block(%u) out of cmd's iov[] has been touched!\n", dbi);
+ pr_warn("Mostly it will be a bug of userspace, please have a check!\n");
+
+ if (dbi >= udev->dbi_thresh) {
+ /* Extern the udev->dbi_thresh to dbi + 1 */
+ udev->dbi_thresh = dbi + 1;
+ udev->dbi_max = dbi;
+ }
+
+ page = radix_tree_lookup(&udev->data_blocks, dbi);
+ if (!page) {
+ page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!page) {
+ mutex_unlock(&udev->cmdr_lock);
+ return NULL;
+ }
+
+ ret = radix_tree_insert(&udev->data_blocks, dbi, page);
+ if (ret) {
+ mutex_unlock(&udev->cmdr_lock);
+ __free_page(page);
+ return NULL;
+ }
+
+ /*
+ * Since this case is rare in page fault routine, here we
+ * will allow the global_db_count >= TCMU_GLOBAL_MAX_BLOCKS
+ * to reduce possible page fault call trace.
+ */
+ atomic_inc(&global_db_count);
+ }
+ mutex_unlock(&udev->cmdr_lock);
+
+ return page;
+}
+
static int tcmu_vma_fault(struct vm_fault *vmf)
{
struct tcmu_dev *udev = vmf->vma->vm_private_data;
*/
offset = (vmf->pgoff - mi) << PAGE_SHIFT;
- addr = (void *)(unsigned long)info->mem[mi].addr + offset;
- if (info->mem[mi].memtype == UIO_MEM_LOGICAL)
- page = virt_to_page(addr);
- else
+ if (offset < udev->data_off) {
+ /* For the vmalloc()ed cmd area pages */
+ addr = (void *)(unsigned long)info->mem[mi].addr + offset;
page = vmalloc_to_page(addr);
+ } else {
+ uint32_t dbi;
+
+ /* For the dynamically growing data area pages */
+ dbi = (offset - udev->data_off) / DATA_BLOCK_SIZE;
+ page = tcmu_try_get_block_page(udev, dbi);
+ if (!page)
+ return VM_FAULT_NOPAGE;
+ }
+
get_page(page);
vmf->page = page;
return 0;
if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags))
return -EBUSY;
+ udev->inode = inode;
+
pr_debug("open\n");
return 0;
info->name = str;
- udev->mb_addr = vzalloc(TCMU_RING_SIZE);
+ udev->mb_addr = vzalloc(CMDR_SIZE);
if (!udev->mb_addr) {
ret = -ENOMEM;
goto err_vzalloc;
/* mailbox fits in first part of CMDR space */
udev->cmdr_size = CMDR_SIZE - CMDR_OFF;
udev->data_off = CMDR_SIZE;
- udev->data_size = TCMU_RING_SIZE - CMDR_SIZE;
+ udev->data_size = DATA_SIZE;
+ udev->dbi_thresh = 0; /* Default in Idle state */
+ udev->waiting_global = false;
+ /* Initialise the mailbox of the ring buffer */
mb = udev->mb_addr;
mb->version = TCMU_MAILBOX_VERSION;
mb->flags = TCMU_MAILBOX_FLAG_CAP_OOOC;
WARN_ON(udev->data_size % PAGE_SIZE);
WARN_ON(udev->data_size % DATA_BLOCK_SIZE);
+ INIT_RADIX_TREE(&udev->data_blocks, GFP_KERNEL);
+
info->version = __stringify(TCMU_MAILBOX_VERSION);
info->mem[0].name = "tcm-user command & data buffer";
info->mem[0].addr = (phys_addr_t)(uintptr_t)udev->mb_addr;
info->mem[0].size = TCMU_RING_SIZE;
- info->mem[0].memtype = UIO_MEM_VIRTUAL;
+ info->mem[0].memtype = UIO_MEM_NONE;
info->irqcontrol = tcmu_irqcontrol;
info->irq = UIO_IRQ_CUSTOM;
if (ret)
goto err_netlink;
+ mutex_lock(&root_udev_mutex);
+ list_add(&udev->node, &root_udev);
+ mutex_unlock(&root_udev_mutex);
+
return 0;
err_netlink:
return udev->uio_info.uio_dev ? true : false;
}
+static void tcmu_blocks_release(struct tcmu_dev *udev)
+{
+ int i;
+ struct page *page;
+
+ /* Try to release all block pages */
+ mutex_lock(&udev->cmdr_lock);
+ for (i = 0; i <= udev->dbi_max; i++) {
+ page = radix_tree_delete(&udev->data_blocks, i);
+ if (page) {
+ __free_page(page);
+ atomic_dec(&global_db_count);
+ }
+ }
+ mutex_unlock(&udev->cmdr_lock);
+}
+
static void tcmu_free_device(struct se_device *dev)
{
struct tcmu_dev *udev = TCMU_DEV(dev);
del_timer_sync(&udev->timeout);
+ mutex_lock(&root_udev_mutex);
+ list_del(&udev->node);
+ mutex_unlock(&root_udev_mutex);
+
vfree(udev->mb_addr);
/* Upper layer should drain all requests before calling this */
spin_unlock_irq(&udev->commands_lock);
WARN_ON(!all_expired);
+ tcmu_blocks_release(udev);
+
if (tcmu_dev_configured(udev)) {
tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name,
udev->uio_info.uio_dev->minor);
.tb_dev_attrib_attrs = NULL,
};
+static int unmap_thread_fn(void *data)
+{
+ struct tcmu_dev *udev;
+ loff_t off;
+ uint32_t start, end, block;
+ struct page *page;
+ int i;
+
+ while (1) {
+ DEFINE_WAIT(__wait);
+
+ prepare_to_wait(&unmap_wait, &__wait, TASK_INTERRUPTIBLE);
+ schedule();
+ finish_wait(&unmap_wait, &__wait);
+
+ if (kthread_should_stop())
+ break;
+
+ mutex_lock(&root_udev_mutex);
+ list_for_each_entry(udev, &root_udev, node) {
+ mutex_lock(&udev->cmdr_lock);
+
+ /* Try to complete the finished commands first */
+ tcmu_handle_completions(udev);
+
+ /* Skip the udevs waiting the global pool or in idle */
+ if (udev->waiting_global || !udev->dbi_thresh) {
+ mutex_unlock(&udev->cmdr_lock);
+ continue;
+ }
+
+ end = udev->dbi_max + 1;
+ block = find_last_bit(udev->data_bitmap, end);
+ if (block == udev->dbi_max) {
+ /*
+ * The last bit is dbi_max, so there is
+ * no need to shrink any blocks.
+ */
+ mutex_unlock(&udev->cmdr_lock);
+ continue;
+ } else if (block == end) {
+ /* The current udev will goto idle state */
+ udev->dbi_thresh = start = 0;
+ udev->dbi_max = 0;
+ } else {
+ udev->dbi_thresh = start = block + 1;
+ udev->dbi_max = block;
+ }
+
+ /* Here will truncate the data area from off */
+ off = udev->data_off + start * DATA_BLOCK_SIZE;
+ unmap_mapping_range(udev->inode->i_mapping, off, 0, 1);
+
+ /* Release the block pages */
+ for (i = start; i < end; i++) {
+ page = radix_tree_delete(&udev->data_blocks, i);
+ if (page) {
+ __free_page(page);
+ atomic_dec(&global_db_count);
+ }
+ }
+ mutex_unlock(&udev->cmdr_lock);
+ }
+
+ /*
+ * Try to wake up the udevs who are waiting
+ * for the global data pool.
+ */
+ list_for_each_entry(udev, &root_udev, node) {
+ if (udev->waiting_global)
+ wake_up(&udev->wait_cmdr);
+ }
+ mutex_unlock(&root_udev_mutex);
+ }
+
+ return 0;
+}
+
static int __init tcmu_module_init(void)
{
int ret, i, len = 0;
if (ret)
goto out_attrs;
+ init_waitqueue_head(&unmap_wait);
+ unmap_thread = kthread_run(unmap_thread_fn, NULL, "tcmu_unmap");
+ if (IS_ERR(unmap_thread)) {
+ ret = PTR_ERR(unmap_thread);
+ goto out_unreg_transport;
+ }
+
return 0;
+out_unreg_transport:
+ target_backend_unregister(&tcmu_ops);
out_attrs:
kfree(tcmu_attrs);
out_unreg_genl:
static void __exit tcmu_module_exit(void)
{
+ kthread_stop(unmap_thread);
target_backend_unregister(&tcmu_ops);
kfree(tcmu_attrs);
genl_unregister_family(&tcmu_genl_family);
projects / linux-2.6-block.git / commitdiff