We do this automatically in get_sb_bdev() from the set_bdev_super() callback. Filesystems that have their own private backing_dev_info must assign that in ->fill_super(). Note that ->s_bdi assignment is required for proper writeback! Signed-off-by: Jens Axboe <jens.axboe@xxxxxxxxxx> --- fs/btrfs/disk-io.c | 1 + fs/fuse/inode.c | 2 ++ fs/super.c | 6 ++++++ fs/sync.c | 9 ++++++++- fs/ubifs/super.c | 1 + include/linux/fs.h | 1 + 6 files changed, 19 insertions(+), 1 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 15831d5..8b81927 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1600,6 +1600,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, sb->s_blocksize = 4096; sb->s_blocksize_bits = blksize_bits(4096); + sb->s_bdi = &fs_info->bdi; /* * we set the i_size on the btree inode to the max possible int. diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 4567db6..e5dbecd 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -894,6 +894,8 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) if (err) goto err_put_conn; + sb->s_bdi = &fc->bdi; + /* Handle umasking inside the fuse code */ if (sb->s_flags & MS_POSIXACL) fc->dont_mask = 1; diff --git a/fs/super.c b/fs/super.c index 9cda337..b03fea8 100644 --- a/fs/super.c +++ b/fs/super.c @@ -707,6 +707,12 @@ static int set_bdev_super(struct super_block *s, void *data) { s->s_bdev = data; s->s_dev = s->s_bdev->bd_dev; + + /* + * We set the bdi here to the queue backing, file systems can + * overwrite this in ->fill_super() + */ + s->s_bdi = &bdev_get_queue(s->s_bdev)->backing_dev_info; return 0; } diff --git a/fs/sync.c b/fs/sync.c index 103cc7f..8582c34 100644 --- a/fs/sync.c +++ b/fs/sync.c @@ -27,6 +27,13 @@ */ static int __sync_filesystem(struct super_block *sb, int wait) { + /* + * This should be safe, as we require bdi backing to actually + * write out data in the first place + */ + if (!sb->s_bdi) + return 0; + /* Avoid doing twice syncing and cache pruning for quota sync */ if (!wait) { writeout_quota_sb(sb, -1); @@ -101,7 +108,7 @@ restart: spin_unlock(&sb_lock); down_read(&sb->s_umount); - if (!(sb->s_flags & MS_RDONLY) && sb->s_root) + if (!(sb->s_flags & MS_RDONLY) && sb->s_root && sb->s_bdi) __sync_filesystem(sb, wait); up_read(&sb->s_umount); diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c index 51763aa..c4af069 100644 --- a/fs/ubifs/super.c +++ b/fs/ubifs/super.c @@ -1980,6 +1980,7 @@ static int ubifs_fill_super(struct super_block *sb, void *data, int silent) if (err) goto out_bdi; + sb->s_bdi = &c->bdi; sb->s_fs_info = c; sb->s_magic = UBIFS_SUPER_MAGIC; sb->s_blocksize = UBIFS_BLOCK_SIZE; diff --git a/include/linux/fs.h b/include/linux/fs.h index 26da98f..940f2a8 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1343,6 +1343,7 @@ struct super_block { int s_nr_dentry_unused; /* # of dentry on lru */ struct block_device *s_bdev; + struct backing_dev_info *s_bdi; struct mtd_info *s_mtd; struct list_head s_instances; struct quota_info s_dquot; /* Diskquota specific options */ -- 1.6.4.1.207.g68ea -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html