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path: root/drivers/target/target_core_user.c
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Diffstat (limited to 'drivers/target/target_core_user.c')
-rw-r--r--drivers/target/target_core_user.c170
1 files changed, 166 insertions, 4 deletions
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 60c8a87b7a88..511168bec159 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -121,6 +121,7 @@ struct tcmu_dev {
#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;
@@ -875,6 +876,11 @@ static sense_reason_t queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, int *scsi_err)
*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;
@@ -1260,7 +1266,7 @@ static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name)
return &udev->se_dev;
}
-static bool run_cmdr_queue(struct tcmu_dev *udev)
+static bool run_cmdr_queue(struct tcmu_dev *udev, bool fail)
{
struct tcmu_cmd *tcmu_cmd, *tmp_cmd;
LIST_HEAD(cmds);
@@ -1271,7 +1277,7 @@ static bool run_cmdr_queue(struct tcmu_dev *udev)
if (list_empty(&udev->cmdr_queue))
return true;
- pr_debug("running %s's cmdr queue\n", udev->name);
+ pr_debug("running %s's cmdr queue forcefail %d\n", udev->name, fail);
list_splice_init(&udev->cmdr_queue, &cmds);
@@ -1281,6 +1287,20 @@ static bool run_cmdr_queue(struct tcmu_dev *udev)
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",
@@ -1317,7 +1337,7 @@ static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on)
mutex_lock(&udev->cmdr_lock);
tcmu_handle_completions(udev);
- run_cmdr_queue(udev);
+ run_cmdr_queue(udev, false);
mutex_unlock(&udev->cmdr_lock);
return 0;
@@ -1801,6 +1821,78 @@ static void tcmu_destroy_device(struct se_device *dev)
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_max_data_area_mb, Opt_err,
@@ -2192,6 +2284,70 @@ static ssize_t tcmu_emulate_write_cache_store(struct config_item *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,
@@ -2205,6 +2361,12 @@ static struct configfs_attribute *tcmu_attrib_attrs[] = {
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,
@@ -2220,7 +2382,7 @@ static struct target_backend_ops tcmu_ops = {
.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 void find_free_blocks(void)

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