#include <linux/highmem.h>
#include <linux/configfs.h>
#include <linux/mutex.h>
-#include <linux/kthread.h>
+#include <linux/workqueue.h>
#include <net/genetlink.h>
#include <scsi/scsi_common.h>
#include <scsi/scsi_proto.h>
* the total size is 256K * PAGE_SIZE.
*/
#define DATA_BLOCK_SIZE PAGE_SIZE
-#define DATA_BLOCK_BITS (256 * 1024)
+#define DATA_BLOCK_SHIFT PAGE_SHIFT
+#define DATA_BLOCK_BITS_DEF (256 * 1024)
#define DATA_SIZE (DATA_BLOCK_BITS * DATA_BLOCK_SIZE)
-#define DATA_BLOCK_INIT_BITS 128
+
+#define TCMU_MBS_TO_BLOCKS(_mbs) (_mbs << (20 - DATA_BLOCK_SHIFT))
+#define TCMU_BLOCKS_TO_MBS(_blocks) (_blocks >> (20 - DATA_BLOCK_SHIFT))
/* 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)
+/*
+ * Default number of global data blocks(512K * PAGE_SIZE)
+ * when the unmap thread will be started.
+ */
+#define TCMU_GLOBAL_MAX_BLOCKS_DEF (512 * 1024)
static u8 tcmu_kern_cmd_reply_supported;
struct tcmu_dev {
struct list_head node;
struct kref kref;
+
struct se_device se_dev;
char *name;
#define TCMU_DEV_BIT_OPEN 0
#define TCMU_DEV_BIT_BROKEN 1
+#define TCMU_DEV_BIT_BLOCKED 2
unsigned long flags;
struct uio_info uio_info;
/* Must add data_off and mb_addr to get the address */
size_t data_off;
size_t data_size;
+ uint32_t max_blocks;
+ size_t ring_size;
- wait_queue_head_t wait_cmdr;
struct mutex cmdr_lock;
+ struct list_head cmdr_queue;
- bool waiting_global;
uint32_t dbi_max;
uint32_t dbi_thresh;
- DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS);
+ unsigned long *data_bitmap;
struct radix_tree_root data_blocks;
struct idr commands;
- spinlock_t commands_lock;
- struct timer_list timeout;
+ struct timer_list cmd_timer;
unsigned int cmd_time_out;
+ struct timer_list qfull_timer;
+ int qfull_time_out;
+
+ struct list_head timedout_entry;
+
spinlock_t nl_cmd_lock;
struct tcmu_nl_cmd curr_nl_cmd;
/* wake up threads waiting on curr_nl_cmd */
struct tcmu_cmd {
struct se_cmd *se_cmd;
struct tcmu_dev *tcmu_dev;
+ struct list_head cmdr_queue_entry;
uint16_t cmd_id;
#define TCMU_CMD_BIT_EXPIRED 0
unsigned long flags;
};
-
-static struct task_struct *unmap_thread;
-static wait_queue_head_t unmap_wait;
+/*
+ * To avoid dead lock the mutex lock order should always be:
+ *
+ * mutex_lock(&root_udev_mutex);
+ * ...
+ * mutex_lock(&tcmu_dev->cmdr_lock);
+ * mutex_unlock(&tcmu_dev->cmdr_lock);
+ * ...
+ * mutex_unlock(&root_udev_mutex);
+ */
static DEFINE_MUTEX(root_udev_mutex);
static LIST_HEAD(root_udev);
-static atomic_t global_db_count = ATOMIC_INIT(0);
+static DEFINE_SPINLOCK(timed_out_udevs_lock);
+static LIST_HEAD(timed_out_udevs);
static struct kmem_cache *tcmu_cmd_cache;
+static atomic_t global_db_count = ATOMIC_INIT(0);
+static struct delayed_work tcmu_unmap_work;
+static int tcmu_global_max_blocks = TCMU_GLOBAL_MAX_BLOCKS_DEF;
+
+static int tcmu_set_global_max_data_area(const char *str,
+ const struct kernel_param *kp)
+{
+ int ret, max_area_mb;
+
+ ret = kstrtoint(str, 10, &max_area_mb);
+ if (ret)
+ return -EINVAL;
+
+ if (max_area_mb <= 0) {
+ pr_err("global_max_data_area must be larger than 0.\n");
+ return -EINVAL;
+ }
+
+ tcmu_global_max_blocks = TCMU_MBS_TO_BLOCKS(max_area_mb);
+ if (atomic_read(&global_db_count) > tcmu_global_max_blocks)
+ schedule_delayed_work(&tcmu_unmap_work, 0);
+ else
+ cancel_delayed_work_sync(&tcmu_unmap_work);
+
+ return 0;
+}
+
+static int tcmu_get_global_max_data_area(char *buffer,
+ const struct kernel_param *kp)
+{
+ return sprintf(buffer, "%d", TCMU_BLOCKS_TO_MBS(tcmu_global_max_blocks));
+}
+
+static const struct kernel_param_ops tcmu_global_max_data_area_op = {
+ .set = tcmu_set_global_max_data_area,
+ .get = tcmu_get_global_max_data_area,
+};
+
+module_param_cb(global_max_data_area_mb, &tcmu_global_max_data_area_op, NULL,
+ S_IWUSR | S_IRUGO);
+MODULE_PARM_DESC(global_max_data_area_mb,
+ "Max MBs allowed to be allocated to all the tcmu device's "
+ "data areas.");
+
/* multicast group */
enum tcmu_multicast_groups {
TCMU_MCGRP_CONFIG,
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;
- }
+ tcmu_global_max_blocks)
+ schedule_delayed_work(&tcmu_unmap_work, 0);
/* try to get new page from the mm */
page = alloc_page(GFP_KERNEL);
{
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 false;
}
return true;
-
-err:
- udev->waiting_global = true;
- /* Try to wake up the unmap thread */
- wake_up(&unmap_wait);
- return false;
}
static inline struct page *
if (!tcmu_cmd)
return NULL;
+ INIT_LIST_HEAD(&tcmu_cmd->cmdr_queue_entry);
tcmu_cmd->se_cmd = se_cmd;
tcmu_cmd->tcmu_dev = udev;
static inline void tcmu_flush_dcache_range(void *vaddr, size_t size)
{
unsigned long offset = offset_in_page(vaddr);
+ void *start = vaddr - offset;
size = round_up(size+offset, PAGE_SIZE);
- vaddr -= offset;
while (size) {
- flush_dcache_page(virt_to_page(vaddr));
+ flush_dcache_page(virt_to_page(start));
+ start += PAGE_SIZE;
size -= PAGE_SIZE;
}
}
return size - head;
}
-static inline void new_iov(struct iovec **iov, int *iov_cnt,
- struct tcmu_dev *udev)
+static inline void new_iov(struct iovec **iov, int *iov_cnt)
{
struct iovec *iovec;
return (size_t)iov->iov_base + iov->iov_len;
}
-static int scatter_data_area(struct tcmu_dev *udev,
+static void 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)
to = kmap_atomic(page);
}
- copy_bytes = min_t(size_t, sg_remaining,
- block_remaining);
+ /*
+ * Covert to virtual offset of the ring data area.
+ */
to_offset = get_block_offset_user(udev, dbi,
block_remaining);
+ /*
+ * The following code will gather and map the blocks
+ * to the same iovec when the blocks are all next to
+ * each other.
+ */
+ copy_bytes = min_t(size_t, sg_remaining,
+ block_remaining);
if (*iov_cnt != 0 &&
to_offset == iov_tail(*iov)) {
+ /*
+ * Will append to the current iovec, because
+ * the current block page is next to the
+ * previous one.
+ */
(*iov)->iov_len += copy_bytes;
} else {
- new_iov(iov, iov_cnt, udev);
+ /*
+ * Will allocate a new iovec because we are
+ * first time here or the current block page
+ * is not next to the previous one.
+ */
+ new_iov(iov, iov_cnt);
(*iov)->iov_base = (void __user *)to_offset;
(*iov)->iov_len = copy_bytes;
}
+
if (copy_data) {
offset = DATA_BLOCK_SIZE - block_remaining;
memcpy(to + offset,
copy_bytes);
tcmu_flush_dcache_range(to, copy_bytes);
}
+
sg_remaining -= copy_bytes;
block_remaining -= copy_bytes;
}
kunmap_atomic(from - sg->offset);
}
+
if (to)
kunmap_atomic(to);
-
- return 0;
}
static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
static inline size_t spc_bitmap_free(unsigned long *bitmap, uint32_t thresh)
{
- return DATA_BLOCK_SIZE * (thresh - bitmap_weight(bitmap, thresh));
+ return thresh - bitmap_weight(bitmap, thresh);
}
/*
/* try to check and get the data blocks as needed */
space = spc_bitmap_free(udev->data_bitmap, udev->dbi_thresh);
- if (space < data_needed) {
- unsigned long blocks_left = DATA_BLOCK_BITS - udev->dbi_thresh;
- unsigned long grow;
+ if ((space * DATA_BLOCK_SIZE) < data_needed) {
+ unsigned long blocks_left =
+ (udev->max_blocks - udev->dbi_thresh) + space;
if (blocks_left < blocks_needed) {
pr_debug("no data space: only %lu available, but ask for %zu\n",
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;
- }
+ udev->dbi_thresh += blocks_needed;
+ if (udev->dbi_thresh > udev->max_blocks)
+ udev->dbi_thresh = udev->max_blocks;
}
return tcmu_get_empty_blocks(udev, cmd);
return command_size;
}
-static int tcmu_setup_cmd_timer(struct tcmu_cmd *tcmu_cmd)
+static int tcmu_setup_cmd_timer(struct tcmu_cmd *tcmu_cmd, unsigned int tmo,
+ struct timer_list *timer)
{
struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
- unsigned long tmo = udev->cmd_time_out;
int cmd_id;
if (tcmu_cmd->cmd_id)
- return 0;
+ goto setup_timer;
cmd_id = idr_alloc(&udev->commands, tcmu_cmd, 1, USHRT_MAX, GFP_NOWAIT);
if (cmd_id < 0) {
}
tcmu_cmd->cmd_id = cmd_id;
+ pr_debug("allocated cmd %u for dev %s tmo %lu\n", tcmu_cmd->cmd_id,
+ udev->name, tmo / MSEC_PER_SEC);
+
+setup_timer:
if (!tmo)
return 0;
tcmu_cmd->deadline = round_jiffies_up(jiffies + msecs_to_jiffies(tmo));
- mod_timer(&udev->timeout, tcmu_cmd->deadline);
+ mod_timer(timer, tcmu_cmd->deadline);
return 0;
}
-static sense_reason_t
-tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
+static int add_to_cmdr_queue(struct tcmu_cmd *tcmu_cmd)
+{
+ struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
+ unsigned int tmo;
+ int ret;
+
+ /*
+ * For backwards compat if qfull_time_out is not set use
+ * cmd_time_out and if that's not set use the default time out.
+ */
+ if (!udev->qfull_time_out)
+ return -ETIMEDOUT;
+ else if (udev->qfull_time_out > 0)
+ tmo = udev->qfull_time_out;
+ else if (udev->cmd_time_out)
+ tmo = udev->cmd_time_out;
+ else
+ tmo = TCMU_TIME_OUT;
+
+ ret = tcmu_setup_cmd_timer(tcmu_cmd, tmo, &udev->qfull_timer);
+ if (ret)
+ return ret;
+
+ list_add_tail(&tcmu_cmd->cmdr_queue_entry, &udev->cmdr_queue);
+ pr_debug("adding cmd %u on dev %s to ring space wait queue\n",
+ tcmu_cmd->cmd_id, udev->name);
+ return 0;
+}
+
+/**
+ * queue_cmd_ring - queue cmd to ring or internally
+ * @tcmu_cmd: cmd to queue
+ * @scsi_err: TCM error code if failure (-1) returned.
+ *
+ * Returns:
+ * -1 we cannot queue internally or to the ring.
+ * 0 success
+ * 1 internally queued to wait for ring memory to free.
+ */
+static sense_reason_t queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, int *scsi_err)
{
struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
bool copy_to_data_area;
size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
- if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags))
- return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ *scsi_err = TCM_NO_SENSE;
+
+ if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) {
+ *scsi_err = TCM_LUN_BUSY;
+ return -1;
+ }
+
+ if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) {
+ *scsi_err = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ return -1;
+ }
/*
* Must be a certain minimum size for response sense info, but
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);
- mutex_lock(&udev->cmdr_lock);
+ if (!list_empty(&udev->cmdr_queue))
+ goto queue;
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);
- mutex_unlock(&udev->cmdr_lock);
- return TCM_INVALID_CDB_FIELD;
+ *scsi_err = TCM_INVALID_CDB_FIELD;
+ return -1;
}
- 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");
- mutex_unlock(&udev->cmdr_lock);
- if (udev->cmd_time_out)
- ret = schedule_timeout(
- msecs_to_jiffies(udev->cmd_time_out));
- else
- ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT));
- finish_wait(&udev->wait_cmdr, &__wait);
- if (!ret) {
- pr_warn("tcmu: command timed out\n");
- return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
- }
-
- mutex_lock(&udev->cmdr_lock);
-
- /* We dropped cmdr_lock, cmd_head is stale */
- cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */
+ if (!is_ring_space_avail(udev, tcmu_cmd, command_size, data_length)) {
+ /*
+ * Don't leave commands partially setup because the unmap
+ * thread might need the blocks to make forward progress.
+ */
+ tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cur);
+ tcmu_cmd_reset_dbi_cur(tcmu_cmd);
+ goto queue;
}
/* Insert a PAD if end-of-ring space is too small */
iov_cnt = 0;
copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE
|| se_cmd->se_cmd_flags & SCF_BIDI);
- 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;
- }
+ scatter_data_area(udev, tcmu_cmd, se_cmd->t_data_sg,
+ se_cmd->t_data_nents, &iov, &iov_cnt,
+ copy_to_data_area);
entry->req.iov_cnt = iov_cnt;
/* Handle BIDI commands */
iov_cnt = 0;
if (se_cmd->se_cmd_flags & SCF_BIDI) {
iov++;
- 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;
- }
+ scatter_data_area(udev, tcmu_cmd, se_cmd->t_bidi_data_sg,
+ se_cmd->t_bidi_data_nents, &iov, &iov_cnt,
+ false);
}
entry->req.iov_bidi_cnt = iov_cnt;
- ret = tcmu_setup_cmd_timer(tcmu_cmd);
+ ret = tcmu_setup_cmd_timer(tcmu_cmd, udev->cmd_time_out,
+ &udev->cmd_timer);
if (ret) {
tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cnt);
mutex_unlock(&udev->cmdr_lock);
- return TCM_OUT_OF_RESOURCES;
+
+ *scsi_err = TCM_OUT_OF_RESOURCES;
+ return -1;
}
entry->hdr.cmd_id = tcmu_cmd->cmd_id;
UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size);
tcmu_flush_dcache_range(mb, sizeof(*mb));
- mutex_unlock(&udev->cmdr_lock);
/* TODO: only if FLUSH and FUA? */
uio_event_notify(&udev->uio_info);
- if (udev->cmd_time_out)
- mod_timer(&udev->timeout, round_jiffies_up(jiffies +
- msecs_to_jiffies(udev->cmd_time_out)));
+ return 0;
+
+queue:
+ if (add_to_cmdr_queue(tcmu_cmd)) {
+ *scsi_err = TCM_OUT_OF_RESOURCES;
+ return -1;
+ }
- return TCM_NO_SENSE;
+ return 1;
}
static sense_reason_t
tcmu_queue_cmd(struct se_cmd *se_cmd)
{
+ struct se_device *se_dev = se_cmd->se_dev;
+ struct tcmu_dev *udev = TCMU_DEV(se_dev);
struct tcmu_cmd *tcmu_cmd;
- sense_reason_t ret;
+ sense_reason_t scsi_ret;
+ int ret;
tcmu_cmd = tcmu_alloc_cmd(se_cmd);
if (!tcmu_cmd)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
- ret = tcmu_queue_cmd_ring(tcmu_cmd);
- if (ret != TCM_NO_SENSE) {
- pr_err("TCMU: Could not queue command\n");
-
+ mutex_lock(&udev->cmdr_lock);
+ ret = queue_cmd_ring(tcmu_cmd, &scsi_ret);
+ mutex_unlock(&udev->cmdr_lock);
+ if (ret < 0)
tcmu_free_cmd(tcmu_cmd);
- }
-
- return ret;
+ return scsi_ret;
}
static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *entry)
}
WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD);
- spin_lock(&udev->commands_lock);
cmd = idr_remove(&udev->commands, entry->hdr.cmd_id);
- spin_unlock(&udev->commands_lock);
-
if (!cmd) {
- pr_err("cmd_id not found, ring is broken\n");
+ pr_err("cmd_id %u not found, ring is broken\n",
+ entry->hdr.cmd_id);
set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags);
break;
}
handled++;
}
- if (mb->cmd_tail == mb->cmd_head)
- del_timer(&udev->timeout); /* no more pending cmds */
+ if (mb->cmd_tail == mb->cmd_head) {
+ /* no more pending commands */
+ del_timer(&udev->cmd_timer);
- wake_up(&udev->wait_cmdr);
+ if (list_empty(&udev->cmdr_queue)) {
+ /*
+ * no more pending or waiting commands so try to
+ * reclaim blocks if needed.
+ */
+ if (atomic_read(&global_db_count) >
+ tcmu_global_max_blocks)
+ schedule_delayed_work(&tcmu_unmap_work, 0);
+ }
+ }
return handled;
}
static int tcmu_check_expired_cmd(int id, void *p, void *data)
{
struct tcmu_cmd *cmd = p;
+ struct tcmu_dev *udev = cmd->tcmu_dev;
+ u8 scsi_status;
+ struct se_cmd *se_cmd;
+ bool is_running;
if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags))
return 0;
if (!time_after(jiffies, cmd->deadline))
return 0;
- set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags);
- target_complete_cmd(cmd->se_cmd, SAM_STAT_CHECK_CONDITION);
- cmd->se_cmd = NULL;
+ is_running = list_empty(&cmd->cmdr_queue_entry);
+ se_cmd = cmd->se_cmd;
+
+ if (is_running) {
+ /*
+ * If cmd_time_out is disabled but qfull is set deadline
+ * will only reflect the qfull timeout. Ignore it.
+ */
+ if (!udev->cmd_time_out)
+ return 0;
+
+ set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags);
+ /*
+ * target_complete_cmd will translate this to LUN COMM FAILURE
+ */
+ scsi_status = SAM_STAT_CHECK_CONDITION;
+ } else {
+ list_del_init(&cmd->cmdr_queue_entry);
+
+ idr_remove(&udev->commands, id);
+ tcmu_free_cmd(cmd);
+ scsi_status = SAM_STAT_TASK_SET_FULL;
+ }
+
+ pr_debug("Timing out cmd %u on dev %s that is %s.\n",
+ id, udev->name, is_running ? "inflight" : "queued");
+ target_complete_cmd(se_cmd, scsi_status);
return 0;
}
-static void tcmu_device_timedout(struct timer_list *t)
+static void tcmu_device_timedout(struct tcmu_dev *udev)
{
- struct tcmu_dev *udev = from_timer(udev, t, timeout);
- unsigned long flags;
+ spin_lock(&timed_out_udevs_lock);
+ if (list_empty(&udev->timedout_entry))
+ list_add_tail(&udev->timedout_entry, &timed_out_udevs);
+ spin_unlock(&timed_out_udevs_lock);
- spin_lock_irqsave(&udev->commands_lock, flags);
- idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL);
- spin_unlock_irqrestore(&udev->commands_lock, flags);
+ schedule_delayed_work(&tcmu_unmap_work, 0);
+}
- /* Try to wake up the ummap thread */
- wake_up(&unmap_wait);
+static void tcmu_cmd_timedout(struct timer_list *t)
+{
+ struct tcmu_dev *udev = from_timer(udev, t, cmd_timer);
- /*
- * We don't need to wakeup threads on wait_cmdr since they have their
- * own timeout.
- */
+ pr_debug("%s cmd timeout has expired\n", udev->name);
+ tcmu_device_timedout(udev);
+}
+
+static void tcmu_qfull_timedout(struct timer_list *t)
+{
+ struct tcmu_dev *udev = from_timer(udev, t, qfull_timer);
+
+ pr_debug("%s qfull timeout has expired\n", udev->name);
+ tcmu_device_timedout(udev);
}
static int tcmu_attach_hba(struct se_hba *hba, u32 host_id)
udev->hba = hba;
udev->cmd_time_out = TCMU_TIME_OUT;
+ udev->qfull_time_out = -1;
- init_waitqueue_head(&udev->wait_cmdr);
+ udev->max_blocks = DATA_BLOCK_BITS_DEF;
mutex_init(&udev->cmdr_lock);
+ INIT_LIST_HEAD(&udev->timedout_entry);
+ INIT_LIST_HEAD(&udev->cmdr_queue);
idr_init(&udev->commands);
- spin_lock_init(&udev->commands_lock);
- timer_setup(&udev->timeout, tcmu_device_timedout, 0);
+ timer_setup(&udev->qfull_timer, tcmu_qfull_timedout, 0);
+ timer_setup(&udev->cmd_timer, tcmu_cmd_timedout, 0);
init_waitqueue_head(&udev->nl_cmd_wq);
spin_lock_init(&udev->nl_cmd_lock);
return &udev->se_dev;
}
+static bool run_cmdr_queue(struct tcmu_dev *udev, bool fail)
+{
+ struct tcmu_cmd *tcmu_cmd, *tmp_cmd;
+ LIST_HEAD(cmds);
+ bool drained = true;
+ sense_reason_t scsi_ret;
+ int ret;
+
+ if (list_empty(&udev->cmdr_queue))
+ return true;
+
+ pr_debug("running %s's cmdr queue forcefail %d\n", udev->name, fail);
+
+ list_splice_init(&udev->cmdr_queue, &cmds);
+
+ list_for_each_entry_safe(tcmu_cmd, tmp_cmd, &cmds, cmdr_queue_entry) {
+ list_del_init(&tcmu_cmd->cmdr_queue_entry);
+
+ pr_debug("removing cmd %u on dev %s from queue\n",
+ tcmu_cmd->cmd_id, udev->name);
+
+ if (fail) {
+ idr_remove(&udev->commands, tcmu_cmd->cmd_id);
+ /*
+ * We were not able to even start the command, so
+ * fail with busy to allow a retry in case runner
+ * was only temporarily down. If the device is being
+ * removed then LIO core will do the right thing and
+ * fail the retry.
+ */
+ target_complete_cmd(tcmu_cmd->se_cmd, SAM_STAT_BUSY);
+ tcmu_free_cmd(tcmu_cmd);
+ continue;
+ }
+
+ ret = queue_cmd_ring(tcmu_cmd, &scsi_ret);
+ if (ret < 0) {
+ pr_debug("cmd %u on dev %s failed with %u\n",
+ tcmu_cmd->cmd_id, udev->name, scsi_ret);
+
+ idr_remove(&udev->commands, tcmu_cmd->cmd_id);
+ /*
+ * Ignore scsi_ret for now. target_complete_cmd
+ * drops it.
+ */
+ target_complete_cmd(tcmu_cmd->se_cmd,
+ SAM_STAT_CHECK_CONDITION);
+ tcmu_free_cmd(tcmu_cmd);
+ } else if (ret > 0) {
+ pr_debug("ran out of space during cmdr queue run\n");
+ /*
+ * cmd was requeued, so just put all cmds back in
+ * the queue
+ */
+ list_splice_tail(&cmds, &udev->cmdr_queue);
+ drained = false;
+ goto done;
+ }
+ }
+ if (list_empty(&udev->cmdr_queue))
+ del_timer(&udev->qfull_timer);
+done:
+ return drained;
+}
+
static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on)
{
- struct tcmu_dev *tcmu_dev = container_of(info, struct tcmu_dev, uio_info);
+ struct tcmu_dev *udev = 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);
+ mutex_lock(&udev->cmdr_lock);
+ tcmu_handle_completions(udev);
+ run_cmdr_queue(udev, false);
+ mutex_unlock(&udev->cmdr_lock);
return 0;
}
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);
}
/*
- * 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.
+ * Userspace messed up and passed in a address not in the
+ * data iov passed to it.
*/
- 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);
- }
+ pr_err("Invalid addr to data block mapping (dbi %u) on device %s\n",
+ dbi, udev->name);
+ page = NULL;
mutex_unlock(&udev->cmdr_lock);
return page;
dbi = (offset - udev->data_off) / DATA_BLOCK_SIZE;
page = tcmu_try_get_block_page(udev, dbi);
if (!page)
- return VM_FAULT_NOPAGE;
+ return VM_FAULT_SIGBUS;
}
get_page(page);
vma->vm_private_data = udev;
/* Ensure the mmap is exactly the right size */
- if (vma_pages(vma) != (TCMU_RING_SIZE >> PAGE_SHIFT))
+ if (vma_pages(vma) != (udev->ring_size >> PAGE_SHIFT))
return -EINVAL;
return 0;
return -EINVAL;
}
-static void tcmu_blocks_release(struct tcmu_dev *udev)
+static void tcmu_blocks_release(struct radix_tree_root *blocks,
+ int start, int end)
{
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);
+ for (i = start; i < end; i++) {
+ page = radix_tree_delete(blocks, i);
if (page) {
__free_page(page);
atomic_dec(&global_db_count);
}
}
- mutex_unlock(&udev->cmdr_lock);
}
static void tcmu_dev_kref_release(struct kref *kref)
vfree(udev->mb_addr);
udev->mb_addr = NULL;
+ spin_lock_bh(&timed_out_udevs_lock);
+ if (!list_empty(&udev->timedout_entry))
+ list_del(&udev->timedout_entry);
+ spin_unlock_bh(&timed_out_udevs_lock);
+
/* Upper layer should drain all requests before calling this */
- spin_lock_irq(&udev->commands_lock);
+ mutex_lock(&udev->cmdr_lock);
idr_for_each_entry(&udev->commands, cmd, i) {
if (tcmu_check_and_free_pending_cmd(cmd) != 0)
all_expired = false;
}
idr_destroy(&udev->commands);
- spin_unlock_irq(&udev->commands_lock);
WARN_ON(!all_expired);
- tcmu_blocks_release(udev);
+ tcmu_blocks_release(&udev->data_blocks, 0, udev->dbi_max + 1);
+ kfree(udev->data_bitmap);
+ mutex_unlock(&udev->cmdr_lock);
call_rcu(&dev->rcu_head, tcmu_dev_call_rcu);
}
wake_up_all(&udev->nl_cmd_wq);
- return ret;;
+ return ret;
}
static int tcmu_netlink_event(struct tcmu_dev *udev, enum tcmu_genl_cmd cmd,
info = &udev->uio_info;
+ udev->data_bitmap = kzalloc(BITS_TO_LONGS(udev->max_blocks) *
+ sizeof(unsigned long), GFP_KERNEL);
+ if (!udev->data_bitmap) {
+ ret = -ENOMEM;
+ goto err_bitmap_alloc;
+ }
+
udev->mb_addr = vzalloc(CMDR_SIZE);
if (!udev->mb_addr) {
ret = -ENOMEM;
/* mailbox fits in first part of CMDR space */
udev->cmdr_size = CMDR_SIZE - CMDR_OFF;
udev->data_off = CMDR_SIZE;
- udev->data_size = DATA_SIZE;
+ udev->data_size = udev->max_blocks * DATA_BLOCK_SIZE;
udev->dbi_thresh = 0; /* Default in Idle state */
- udev->waiting_global = false;
/* Initialise the mailbox of the ring buffer */
mb = udev->mb_addr;
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].size = udev->ring_size = udev->data_size + CMDR_SIZE;
info->mem[0].memtype = UIO_MEM_NONE;
info->irqcontrol = tcmu_irqcontrol;
vfree(udev->mb_addr);
udev->mb_addr = NULL;
err_vzalloc:
+ kfree(udev->data_bitmap);
+ udev->data_bitmap = NULL;
+err_bitmap_alloc:
kfree(info->name);
info->name = NULL;
{
struct tcmu_dev *udev = TCMU_DEV(dev);
- del_timer_sync(&udev->timeout);
+ del_timer_sync(&udev->cmd_timer);
+ del_timer_sync(&udev->qfull_timer);
mutex_lock(&root_udev_mutex);
list_del(&udev->node);
kref_put(&udev->kref, tcmu_dev_kref_release);
}
+static void tcmu_unblock_dev(struct tcmu_dev *udev)
+{
+ mutex_lock(&udev->cmdr_lock);
+ clear_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags);
+ mutex_unlock(&udev->cmdr_lock);
+}
+
+static void tcmu_block_dev(struct tcmu_dev *udev)
+{
+ mutex_lock(&udev->cmdr_lock);
+
+ if (test_and_set_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags))
+ goto unlock;
+
+ /* complete IO that has executed successfully */
+ tcmu_handle_completions(udev);
+ /* fail IO waiting to be queued */
+ run_cmdr_queue(udev, true);
+
+unlock:
+ mutex_unlock(&udev->cmdr_lock);
+}
+
+static void tcmu_reset_ring(struct tcmu_dev *udev, u8 err_level)
+{
+ struct tcmu_mailbox *mb;
+ struct tcmu_cmd *cmd;
+ int i;
+
+ mutex_lock(&udev->cmdr_lock);
+
+ idr_for_each_entry(&udev->commands, cmd, i) {
+ if (!list_empty(&cmd->cmdr_queue_entry))
+ continue;
+
+ pr_debug("removing cmd %u on dev %s from ring (is expired %d)\n",
+ cmd->cmd_id, udev->name,
+ test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags));
+
+ idr_remove(&udev->commands, i);
+ if (!test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) {
+ if (err_level == 1) {
+ /*
+ * Userspace was not able to start the
+ * command or it is retryable.
+ */
+ target_complete_cmd(cmd->se_cmd, SAM_STAT_BUSY);
+ } else {
+ /* hard failure */
+ target_complete_cmd(cmd->se_cmd,
+ SAM_STAT_CHECK_CONDITION);
+ }
+ }
+ tcmu_cmd_free_data(cmd, cmd->dbi_cnt);
+ tcmu_free_cmd(cmd);
+ }
+
+ mb = udev->mb_addr;
+ tcmu_flush_dcache_range(mb, sizeof(*mb));
+ pr_debug("mb last %u head %u tail %u\n", udev->cmdr_last_cleaned,
+ mb->cmd_tail, mb->cmd_head);
+
+ udev->cmdr_last_cleaned = 0;
+ mb->cmd_tail = 0;
+ mb->cmd_head = 0;
+ tcmu_flush_dcache_range(mb, sizeof(*mb));
+
+ del_timer(&udev->cmd_timer);
+
+ mutex_unlock(&udev->cmdr_lock);
+}
+
enum {
Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_hw_max_sectors,
- Opt_nl_reply_supported, Opt_err,
+ Opt_nl_reply_supported, Opt_max_data_area_mb, Opt_err,
};
static match_table_t tokens = {
{Opt_hw_block_size, "hw_block_size=%u"},
{Opt_hw_max_sectors, "hw_max_sectors=%u"},
{Opt_nl_reply_supported, "nl_reply_supported=%d"},
+ {Opt_max_data_area_mb, "max_data_area_mb=%u"},
{Opt_err, NULL}
};
struct tcmu_dev *udev = TCMU_DEV(dev);
char *orig, *ptr, *opts, *arg_p;
substring_t args[MAX_OPT_ARGS];
- int ret = 0, token;
+ int ret = 0, token, tmpval;
opts = kstrdup(page, GFP_KERNEL);
if (!opts)
if (ret < 0)
pr_err("kstrtoint() failed for nl_reply_supported=\n");
break;
+ case Opt_max_data_area_mb:
+ if (dev->export_count) {
+ pr_err("Unable to set max_data_area_mb while exports exist\n");
+ ret = -EINVAL;
+ break;
+ }
+
+ arg_p = match_strdup(&args[0]);
+ if (!arg_p) {
+ ret = -ENOMEM;
+ break;
+ }
+ ret = kstrtoint(arg_p, 0, &tmpval);
+ kfree(arg_p);
+ if (ret < 0) {
+ pr_err("kstrtoint() failed for max_data_area_mb=\n");
+ break;
+ }
+
+ if (tmpval <= 0) {
+ pr_err("Invalid max_data_area %d\n", tmpval);
+ ret = -EINVAL;
+ break;
+ }
+
+ udev->max_blocks = TCMU_MBS_TO_BLOCKS(tmpval);
+ if (udev->max_blocks > tcmu_global_max_blocks) {
+ pr_err("%d is too large. Adjusting max_data_area_mb to global limit of %u\n",
+ tmpval,
+ TCMU_BLOCKS_TO_MBS(tcmu_global_max_blocks));
+ udev->max_blocks = tcmu_global_max_blocks;
+ }
+ break;
default:
break;
}
bl = sprintf(b + bl, "Config: %s ",
udev->dev_config[0] ? udev->dev_config : "NULL");
- bl += sprintf(b + bl, "Size: %zu\n", udev->dev_size);
+ bl += sprintf(b + bl, "Size: %zu ", udev->dev_size);
+ bl += sprintf(b + bl, "MaxDataAreaMB: %u\n",
+ TCMU_BLOCKS_TO_MBS(udev->max_blocks));
return bl;
}
}
CONFIGFS_ATTR(tcmu_, cmd_time_out);
+static ssize_t tcmu_qfull_time_out_show(struct config_item *item, char *page)
+{
+ struct se_dev_attrib *da = container_of(to_config_group(item),
+ struct se_dev_attrib, da_group);
+ struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
+
+ return snprintf(page, PAGE_SIZE, "%ld\n", udev->qfull_time_out <= 0 ?
+ udev->qfull_time_out :
+ udev->qfull_time_out / MSEC_PER_SEC);
+}
+
+static ssize_t tcmu_qfull_time_out_store(struct config_item *item,
+ const char *page, size_t count)
+{
+ struct se_dev_attrib *da = container_of(to_config_group(item),
+ struct se_dev_attrib, da_group);
+ struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
+ s32 val;
+ int ret;
+
+ ret = kstrtos32(page, 0, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val >= 0) {
+ udev->qfull_time_out = val * MSEC_PER_SEC;
+ } else {
+ printk(KERN_ERR "Invalid qfull timeout value %d\n", val);
+ return -EINVAL;
+ }
+ return count;
+}
+CONFIGFS_ATTR(tcmu_, qfull_time_out);
+
+static ssize_t tcmu_max_data_area_mb_show(struct config_item *item, char *page)
+{
+ struct se_dev_attrib *da = container_of(to_config_group(item),
+ struct se_dev_attrib, da_group);
+ struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
+
+ return snprintf(page, PAGE_SIZE, "%u\n",
+ TCMU_BLOCKS_TO_MBS(udev->max_blocks));
+}
+CONFIGFS_ATTR_RO(tcmu_, max_data_area_mb);
+
static ssize_t tcmu_dev_config_show(struct config_item *item, char *page)
{
struct se_dev_attrib *da = container_of(to_config_group(item),
}
CONFIGFS_ATTR(tcmu_, emulate_write_cache);
+static ssize_t tcmu_block_dev_show(struct config_item *item, char *page)
+{
+ struct se_device *se_dev = container_of(to_config_group(item),
+ struct se_device,
+ dev_action_group);
+ struct tcmu_dev *udev = TCMU_DEV(se_dev);
+
+ if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags))
+ return snprintf(page, PAGE_SIZE, "%s\n", "blocked");
+ else
+ return snprintf(page, PAGE_SIZE, "%s\n", "unblocked");
+}
+
+static ssize_t tcmu_block_dev_store(struct config_item *item, const char *page,
+ size_t count)
+{
+ struct se_device *se_dev = container_of(to_config_group(item),
+ struct se_device,
+ dev_action_group);
+ struct tcmu_dev *udev = TCMU_DEV(se_dev);
+ u8 val;
+ int ret;
+
+ ret = kstrtou8(page, 0, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val > 1) {
+ pr_err("Invalid block value %d\n", val);
+ return -EINVAL;
+ }
+
+ if (!val)
+ tcmu_unblock_dev(udev);
+ else
+ tcmu_block_dev(udev);
+ return count;
+}
+CONFIGFS_ATTR(tcmu_, block_dev);
+
+static ssize_t tcmu_reset_ring_store(struct config_item *item, const char *page,
+ size_t count)
+{
+ struct se_device *se_dev = container_of(to_config_group(item),
+ struct se_device,
+ dev_action_group);
+ struct tcmu_dev *udev = TCMU_DEV(se_dev);
+ u8 val;
+ int ret;
+
+ ret = kstrtou8(page, 0, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val != 1 && val != 2) {
+ pr_err("Invalid reset ring value %d\n", val);
+ return -EINVAL;
+ }
+
+ tcmu_reset_ring(udev, val);
+ return count;
+}
+CONFIGFS_ATTR_WO(tcmu_, reset_ring);
+
static struct configfs_attribute *tcmu_attrib_attrs[] = {
&tcmu_attr_cmd_time_out,
+ &tcmu_attr_qfull_time_out,
+ &tcmu_attr_max_data_area_mb,
&tcmu_attr_dev_config,
&tcmu_attr_dev_size,
&tcmu_attr_emulate_write_cache,
static struct configfs_attribute **tcmu_attrs;
+static struct configfs_attribute *tcmu_action_attrs[] = {
+ &tcmu_attr_block_dev,
+ &tcmu_attr_reset_ring,
+ NULL,
+};
+
static struct target_backend_ops tcmu_ops = {
.name = "user",
.owner = THIS_MODULE,
.show_configfs_dev_params = tcmu_show_configfs_dev_params,
.get_device_type = sbc_get_device_type,
.get_blocks = tcmu_get_blocks,
- .tb_dev_attrib_attrs = NULL,
+ .tb_dev_action_attrs = tcmu_action_attrs,
};
-static int unmap_thread_fn(void *data)
+static void find_free_blocks(void)
{
struct tcmu_dev *udev;
loff_t off;
- uint32_t start, end, block;
- struct page *page;
- int i;
+ u32 start, end, block, total_freed = 0;
- while (!kthread_should_stop()) {
- DEFINE_WAIT(__wait);
+ if (atomic_read(&global_db_count) <= tcmu_global_max_blocks)
+ return;
- prepare_to_wait(&unmap_wait, &__wait, TASK_INTERRUPTIBLE);
- schedule();
- finish_wait(&unmap_wait, &__wait);
+ mutex_lock(&root_udev_mutex);
+ list_for_each_entry(udev, &root_udev, node) {
+ mutex_lock(&udev->cmdr_lock);
- if (kthread_should_stop())
- break;
+ /* Try to complete the finished commands first */
+ tcmu_handle_completions(udev);
- mutex_lock(&root_udev_mutex);
- list_for_each_entry(udev, &root_udev, node) {
- mutex_lock(&udev->cmdr_lock);
+ /* Skip the udevs in idle */
+ if (!udev->dbi_thresh) {
+ mutex_unlock(&udev->cmdr_lock);
+ continue;
+ }
- /* Try to complete the finished commands first */
- tcmu_handle_completions(udev);
+ 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 it is not possible
+ * reclaim 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;
+ }
- /* Skip the udevs waiting the global pool or in idle */
- if (udev->waiting_global || !udev->dbi_thresh) {
- mutex_unlock(&udev->cmdr_lock);
- continue;
- }
+ /* 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);
- 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;
- }
+ /* Release the block pages */
+ tcmu_blocks_release(&udev->data_blocks, start, end);
+ mutex_unlock(&udev->cmdr_lock);
- /* 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);
- }
+ total_freed += end - start;
+ pr_debug("Freed %u blocks (total %u) from %s.\n", end - start,
+ total_freed, udev->name);
+ }
+ mutex_unlock(&root_udev_mutex);
- /*
- * 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);
+ if (atomic_read(&global_db_count) > tcmu_global_max_blocks)
+ schedule_delayed_work(&tcmu_unmap_work, msecs_to_jiffies(5000));
+}
+
+static void check_timedout_devices(void)
+{
+ struct tcmu_dev *udev, *tmp_dev;
+ LIST_HEAD(devs);
+
+ spin_lock_bh(&timed_out_udevs_lock);
+ list_splice_init(&timed_out_udevs, &devs);
+
+ list_for_each_entry_safe(udev, tmp_dev, &devs, timedout_entry) {
+ list_del_init(&udev->timedout_entry);
+ spin_unlock_bh(&timed_out_udevs_lock);
+
+ mutex_lock(&udev->cmdr_lock);
+ idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL);
+ mutex_unlock(&udev->cmdr_lock);
+
+ spin_lock_bh(&timed_out_udevs_lock);
}
- return 0;
+ spin_unlock_bh(&timed_out_udevs_lock);
+}
+
+static void tcmu_unmap_work_fn(struct work_struct *work)
+{
+ check_timedout_devices();
+ find_free_blocks();
}
static int __init tcmu_module_init(void)
BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0);
+ INIT_DELAYED_WORK(&tcmu_unmap_work, tcmu_unmap_work_fn);
+
tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache",
sizeof(struct tcmu_cmd),
__alignof__(struct tcmu_cmd),
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);
+ cancel_delayed_work_sync(&tcmu_unmap_work);
target_backend_unregister(&tcmu_ops);
kfree(tcmu_attrs);
genl_unregister_family(&tcmu_genl_family);
projects / linux.git / blobdiff