summaryrefslogtreecommitdiff
path: root/block/blk-sysfs.c
diff options
context:
space:
mode:
authorLuis Chamberlain <mcgrof@kernel.org>2020-06-19 20:47:30 +0000
committerJens Axboe <axboe@kernel.dk>2020-06-24 09:15:58 -0600
commit85e0cbbb8a79537dbc465e9deb449a08b2b092a6 (patch)
treee137eee072e10d10335cd77c043c5797e1136268 /block/blk-sysfs.c
parentb431ef837e3374da0db8ff6683170359aaa0859c (diff)
downloadlwn-85e0cbbb8a79537dbc465e9deb449a08b2b092a6.tar.gz
lwn-85e0cbbb8a79537dbc465e9deb449a08b2b092a6.zip
block: create the request_queue debugfs_dir on registration
We were only creating the request_queue debugfs_dir only for make_request block drivers (multiqueue), but never for request-based block drivers. We did this as we were only creating non-blktrace additional debugfs files on that directory for make_request drivers. However, since blktrace *always* creates that directory anyway, we special-case the use of that directory on blktrace. Other than this being an eye-sore, this exposes request-based block drivers to the same debugfs fragile race that used to exist with make_request block drivers where if we start adding files onto that directory we can later run a race with a double removal of dentries on the directory if we don't deal with this carefully on blktrace. Instead, just simplify things by always creating the request_queue debugfs_dir on request_queue registration. Rename the mutex also to reflect the fact that this is used outside of the blktrace context. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-sysfs.c')
-rw-r--r--block/blk-sysfs.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 561624d4cc4e..be67952e7be2 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -11,6 +11,7 @@
#include <linux/blktrace_api.h>
#include <linux/blk-mq.h>
#include <linux/blk-cgroup.h>
+#include <linux/debugfs.h>
#include "blk.h"
#include "blk-mq.h"
@@ -917,6 +918,9 @@ static void blk_release_queue(struct kobject *kobj)
blk_mq_release(q);
blk_trace_shutdown(q);
+ mutex_lock(&q->debugfs_mutex);
+ debugfs_remove_recursive(q->debugfs_dir);
+ mutex_unlock(&q->debugfs_mutex);
if (queue_is_mq(q))
blk_mq_debugfs_unregister(q);
@@ -989,6 +993,11 @@ int blk_register_queue(struct gendisk *disk)
goto unlock;
}
+ mutex_lock(&q->debugfs_mutex);
+ q->debugfs_dir = debugfs_create_dir(kobject_name(q->kobj.parent),
+ blk_debugfs_root);
+ mutex_unlock(&q->debugfs_mutex);
+
if (queue_is_mq(q)) {
__blk_mq_register_dev(dev, q);
blk_mq_debugfs_register(q);