Add limit_bio_size block sysfs node to limit bio size.
Queue flag QUEUE_FLAG_LIMIT_BIO_SIZE will be set if limit_bio_size is set.
And bio max size will be limited by queue max sectors via
QUEUE_FLAG_LIMIT_BIO_SIZE set.
Signed-off-by: Changheun Lee <nanich.lee@xxxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-block | 10 ++++++++++
Documentation/block/queue-sysfs.rst | 7 +++++++
block/blk-sysfs.c | 3 +++
3 files changed, 20 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index e34cdeeeb9d4..86a7b15410cf 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -316,3 +316,13 @@ Description:
does not complete in this time then the block driver timeout
handler is invoked. That timeout handler can decide to retry
the request, to fail it or to start a device recovery strategy.
+
+What: /sys/block/<disk>/queue/limit_bio_size
+Date: Feb, 2021
+Contact: Changheun Lee <nanich.lee@xxxxxxxxxxx>
+Description:
+ (RW) Toggle for set/clear QUEUE_FLAG_LIMIT_BIO_SIZE queue flag.
+ Queue flag QUEUE_FLAG_LIMIT_BIO_SIZE will be set if limit_bio_size
+ is set. And bio max size will be limited by queue max sectors.
+ QUEUE_FLAG_LIMIT_BIO_SIZE will be cleared if limit_bio_size is
+ cleard. And limit of bio max size will be cleard.
diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst
index 2638d3446b79..cd371a821855 100644
--- a/Documentation/block/queue-sysfs.rst
+++ b/Documentation/block/queue-sysfs.rst
@@ -273,4 +273,11 @@ devices are described in the ZBC (Zoned Block Commands) and ZAC
do not support zone commands, they will be treated as regular block devices
and zoned will report "none".
+limit_bio_size (RW)
+-------------------
+This indicates QUEUE_FLAG_LIMIT_BIO_SIZE queue flag value. And
+QUEUE_FLAG_LIMIT_BIO_SIZE can be changed via set(1)/clear(0) this node.
+bio max size will be limited by queue max sectors via set this node. And
+limit of bio max size will be cleard via clear this node.
+
Jens Axboe <jens.axboe@xxxxxxxxxx>, February 2009
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index b513f1683af0..840d97f427e6 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -288,6 +288,7 @@ QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
QUEUE_SYSFS_BIT_FNS(stable_writes, STABLE_WRITES, 0);
+QUEUE_SYSFS_BIT_FNS(limit_bio_size, LIMIT_BIO_SIZE, 0);
#undef QUEUE_SYSFS_BIT_FNS
static ssize_t queue_zoned_show(struct request_queue *q, char *page)
@@ -615,6 +616,7 @@ QUEUE_RW_ENTRY(queue_nonrot, "rotational");
QUEUE_RW_ENTRY(queue_iostats, "iostats");
QUEUE_RW_ENTRY(queue_random, "add_random");
QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes");
+QUEUE_RW_ENTRY(queue_limit_bio_size, "limit_bio_size");
static struct attribute *queue_attrs[] = {
&queue_requests_entry.attr,
@@ -648,6 +650,7 @@ static struct attribute *queue_attrs[] = {
&queue_rq_affinity_entry.attr,
&queue_iostats_entry.attr,
&queue_stable_writes_entry.attr,
+ &queue_limit_bio_size_entry.attr,
&queue_random_entry.attr,
&queue_poll_entry.attr,
&queue_wc_entry.attr,
--
2.28.0
