diff options
Diffstat (limited to 'drivers/target')
| -rw-r--r-- | drivers/target/target_core_user.c | 170 |
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) |