Allow setting shared_tags through configfs, which could only be set as a
module parameter. For that purpose, delay tag_set initialization from
null_init() to null_add_dev(). Introduce the flag tag_set_initialized to
manage the initialization status of tag_set.
The following parameters can not be set through configfs yet:
timeout
requeue
init_hctx
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
---
This patch will allow running the blktests test cases block/010 and block/022
using the built-in null_blk driver. Corresponding blktests side changes are
drafted here [1].
[1] https://github.com/kawasaki/blktests/tree/shared_tags
drivers/block/null_blk/main.c | 38 ++++++++++++++++---------------
drivers/block/null_blk/null_blk.h | 1 +
2 files changed, 21 insertions(+), 18 deletions(-)
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 36755f263e8e..c3361e521564 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -69,6 +69,7 @@ static LIST_HEAD(nullb_list);
static struct mutex lock;
static int null_major;
static DEFINE_IDA(nullb_indexes);
+static bool tag_set_initialized = false;
static struct blk_mq_tag_set tag_set;
enum {
@@ -165,8 +166,8 @@ static bool g_blocking;
module_param_named(blocking, g_blocking, bool, 0444);
MODULE_PARM_DESC(blocking, "Register as a blocking blk-mq driver device");
-static bool shared_tags;
-module_param(shared_tags, bool, 0444);
+static bool g_shared_tags;
+module_param_named(shared_tags, g_shared_tags, bool, 0444);
MODULE_PARM_DESC(shared_tags, "Share tag set between devices for blk-mq");
static bool g_shared_tag_bitmap;
@@ -426,6 +427,7 @@ NULLB_DEVICE_ATTR(zone_max_open, uint, NULL);
NULLB_DEVICE_ATTR(zone_max_active, uint, NULL);
NULLB_DEVICE_ATTR(virt_boundary, bool, NULL);
NULLB_DEVICE_ATTR(no_sched, bool, NULL);
+NULLB_DEVICE_ATTR(shared_tags, bool, NULL);
NULLB_DEVICE_ATTR(shared_tag_bitmap, bool, NULL);
static ssize_t nullb_device_power_show(struct config_item *item, char *page)
@@ -571,6 +573,7 @@ static struct configfs_attribute *nullb_device_attrs[] = {
&nullb_device_attr_zone_offline,
&nullb_device_attr_virt_boundary,
&nullb_device_attr_no_sched,
+ &nullb_device_attr_shared_tags,
&nullb_device_attr_shared_tag_bitmap,
NULL,
};
@@ -653,10 +656,11 @@ static ssize_t memb_group_features_show(struct config_item *item, char *page)
"badblocks,blocking,blocksize,cache_size,"
"completion_nsec,discard,home_node,hw_queue_depth,"
"irqmode,max_sectors,mbps,memory_backed,no_sched,"
- "poll_queues,power,queue_mode,shared_tag_bitmap,size,"
- "submit_queues,use_per_node_hctx,virt_boundary,zoned,"
- "zone_capacity,zone_max_active,zone_max_open,"
- "zone_nr_conv,zone_offline,zone_readonly,zone_size\n");
+ "poll_queues,power,queue_mode,shared_tag_bitmap,"
+ "shared_tags,size,submit_queues,use_per_node_hctx,"
+ "virt_boundary,zoned,zone_capacity,zone_max_active,"
+ "zone_max_open,zone_nr_conv,zone_offline,zone_readonly,"
+ "zone_size\n");
}
CONFIGFS_ATTR_RO(memb_group_, features);
@@ -738,6 +742,7 @@ static struct nullb_device *null_alloc_dev(void)
dev->zone_max_active = g_zone_max_active;
dev->virt_boundary = g_virt_boundary;
dev->no_sched = g_no_sched;
+ dev->shared_tags = g_shared_tags;
dev->shared_tag_bitmap = g_shared_tag_bitmap;
return dev;
}
@@ -2124,7 +2129,13 @@ static int null_add_dev(struct nullb_device *dev)
goto out_free_nullb;
if (dev->queue_mode == NULL_Q_MQ) {
- if (shared_tags) {
+ if (dev->shared_tags) {
+ if (!tag_set_initialized) {
+ rv = null_init_tag_set(NULL, &tag_set);
+ if (rv)
+ goto out_cleanup_queues;
+ tag_set_initialized = true;
+ }
nullb->tag_set = &tag_set;
rv = 0;
} else {
@@ -2311,18 +2322,12 @@ static int __init null_init(void)
g_submit_queues = 1;
}
- if (g_queue_mode == NULL_Q_MQ && shared_tags) {
- ret = null_init_tag_set(NULL, &tag_set);
- if (ret)
- return ret;
- }
-
config_group_init(&nullb_subsys.su_group);
mutex_init(&nullb_subsys.su_mutex);
ret = configfs_register_subsystem(&nullb_subsys);
if (ret)
- goto err_tagset;
+ return ret;
mutex_init(&lock);
@@ -2349,9 +2354,6 @@ static int __init null_init(void)
unregister_blkdev(null_major, "nullb");
err_conf:
configfs_unregister_subsystem(&nullb_subsys);
-err_tagset:
- if (g_queue_mode == NULL_Q_MQ && shared_tags)
- blk_mq_free_tag_set(&tag_set);
return ret;
}
@@ -2370,7 +2372,7 @@ static void __exit null_exit(void)
}
mutex_unlock(&lock);
- if (g_queue_mode == NULL_Q_MQ && shared_tags)
+ if (tag_set_initialized)
blk_mq_free_tag_set(&tag_set);
}
diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h
index 929f659dd255..7bcfc0922ae8 100644
--- a/drivers/block/null_blk/null_blk.h
+++ b/drivers/block/null_blk/null_blk.h
@@ -119,6 +119,7 @@ struct nullb_device {
bool zoned; /* if device is zoned */
bool virt_boundary; /* virtual boundary on/off for the device */
bool no_sched; /* no IO scheduler for the device */
+ bool shared_tags; /* share tag set between devices for blk-mq */
bool shared_tag_bitmap; /* use hostwide shared tags */
};
--
2.43.0
