5.4-stable review patch. If anyone has any objections, please let me know.
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From: Christoph Hellwig hch@lst.de
[ 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@lst.de Signed-off-by: Christoph Hellwig hch@lst.de Reviewed-by: Jan Kara jack@suse.cz Cc: Miquel Raynal miquel.raynal@bootlin.com Cc: Richard Weinberger richard@nod.at Cc: Vignesh Raghavendra vigneshr@ti.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Stable-dep-of: 4bcda1eaf184 ("mount: handle OOM on mnt_warn_timestamp_expiry") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/super.c | 3 +++ include/linux/fs.h | 1 + 2 files changed, 4 insertions(+)
diff --git a/fs/super.c b/fs/super.c index 47ca7dc0e6c3d..8edf44a2d3dcc 100644 --- a/fs/super.c +++ b/fs/super.c @@ -475,6 +475,8 @@ 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; } @@ -1622,6 +1624,7 @@ 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 d4f5fcc60744d..b21fdce37c37a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1407,6 +1407,7 @@ 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 {