This is a note to let you know that I've just added the patch titled
fs: explicitly unregister per-superblock BDIs
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fs-explicitly-unregister-per-superblock-bdis.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c023bb2972707e78d63919c64568227c19bd857e
Author: Christoph Hellwig <hch@xxxxxx>
Date: Fri Nov 5 13:36:58 2021 -0700
fs: explicitly unregister per-superblock BDIs
[ Upstream commit 0b3ea0926afb8dde70cfab00316ae0a70b93a7cc ]
Add a new SB_I_ flag to mark superblocks that have an ephemeral bdi
associated with them, and unregister it when the superblock is shut
down.
Link: https://lkml.kernel.org/r/20211021124441.668816-4-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Cc: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
Cc: Vignesh Raghavendra <vigneshr@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Stable-dep-of: 4bcda1eaf184 ("mount: handle OOM on mnt_warn_timestamp_expiry")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/super.c b/fs/super.c
index 39d866f7d7c6b..eeb8f745a8bf7 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -486,6 +486,8 @@ void generic_shutdown_super(struct super_block *sb)
spin_unlock(&sb_lock);
up_write(&sb->s_umount);
if (sb->s_bdi != &noop_backing_dev_info) {
+ if (sb->s_iflags & SB_I_PERSB_BDI)
+ bdi_unregister(sb->s_bdi);
bdi_put(sb->s_bdi);
sb->s_bdi = &noop_backing_dev_info;
}
@@ -1592,6 +1594,7 @@ int super_setup_bdi_name(struct super_block *sb, char *fmt, ...)
}
WARN_ON(sb->s_bdi != &noop_backing_dev_info);
sb->s_bdi = bdi;
+ sb->s_iflags |= SB_I_PERSB_BDI;
return 0;
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 27da89d0ed5ac..bf35cf9e312a5 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1476,6 +1476,7 @@ extern int send_sigurg(struct fown_struct *fown);
#define SB_I_UNTRUSTED_MOUNTER 0x00000040
#define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */
+#define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */
/* Possible states of 'frozen' field */
enum {
