tcmu: make cmd timeout configurable

A single daemon could implement multiple types of devices
using multuple types of real devices that may not support
restarting from crashes and/or handling tcmu timeouts. This
makes the cmd timeout configurable, so handlers that do not
support it can turn if off for now.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Mike Christie 2017-03-09 02:42:09 -06:00 committed by Nicholas Bellinger
parent 972c7f1679
commit af980e46a2

View File

@ -112,6 +112,7 @@ struct tcmu_dev {
spinlock_t commands_lock;
struct timer_list timeout;
unsigned int cmd_time_out;
char dev_config[TCMU_CONFIG_LEN];
};
@ -172,7 +173,9 @@ static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd)
tcmu_cmd->se_cmd = se_cmd;
tcmu_cmd->tcmu_dev = udev;
tcmu_cmd->deadline = jiffies + msecs_to_jiffies(TCMU_TIME_OUT);
if (udev->cmd_time_out)
tcmu_cmd->deadline = jiffies +
msecs_to_jiffies(udev->cmd_time_out);
idr_preload(GFP_KERNEL);
spin_lock_irq(&udev->commands_lock);
@ -451,7 +454,11 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
pr_debug("sleeping for ring space\n");
spin_unlock_irq(&udev->cmdr_lock);
ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT));
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");
@ -526,8 +533,9 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
/* TODO: only if FLUSH and FUA? */
uio_event_notify(&udev->uio_info);
mod_timer(&udev->timeout,
round_jiffies_up(jiffies + msecs_to_jiffies(TCMU_TIME_OUT)));
if (udev->cmd_time_out)
mod_timer(&udev->timeout, round_jiffies_up(jiffies +
msecs_to_jiffies(udev->cmd_time_out)));
return TCM_NO_SENSE;
}
@ -742,6 +750,7 @@ static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name)
}
udev->hba = hba;
udev->cmd_time_out = TCMU_TIME_OUT;
init_waitqueue_head(&udev->wait_cmdr);
spin_lock_init(&udev->cmdr_lock);
@ -1037,7 +1046,7 @@ static void tcmu_free_device(struct se_device *dev)
enum {
Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_hw_max_sectors,
Opt_err,
Opt_cmd_time_out, Opt_err,
};
static match_table_t tokens = {
@ -1045,6 +1054,7 @@ static match_table_t tokens = {
{Opt_dev_size, "dev_size=%u"},
{Opt_hw_block_size, "hw_block_size=%u"},
{Opt_hw_max_sectors, "hw_max_sectors=%u"},
{Opt_cmd_time_out, "cmd_time_out=%u"},
{Opt_err, NULL}
};
@ -1111,6 +1121,23 @@ static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev,
if (ret < 0)
pr_err("kstrtoul() failed for dev_size=\n");
break;
case Opt_cmd_time_out:
if (tcmu_dev_configured(udev)) {
pr_err("Can not update cmd_time_out after device has been configured.\n");
ret = -EINVAL;
break;
}
arg_p = match_strdup(&args[0]);
if (!arg_p) {
ret = -ENOMEM;
break;
}
ret = kstrtouint(arg_p, 0, &udev->cmd_time_out);
kfree(arg_p);
if (ret < 0)
pr_err("kstrtouint() failed for cmd_time_out=\n");
udev->cmd_time_out *= MSEC_PER_SEC;
break;
case Opt_hw_block_size:
ret = tcmu_set_dev_attrib(&args[0],
&(dev->dev_attrib.hw_block_size));
@ -1138,7 +1165,9 @@ static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b)
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, "Cmd Time Out: %lu\n",
udev->cmd_time_out / MSEC_PER_SEC);
return bl;
}