From: Jan Kara Date: Tue, 3 Jul 2012 14:45:32 +0000 (+0200) Subject: vfs: Make sys_sync writeout also block device inodes X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a8c7176b6ded413d5044a00f1d05477b95a6d7ad;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git vfs: Make sys_sync writeout also block device inodes In case block device does not have filesystem mounted on it, sys_sync will just ignore it and doesn't writeout its dirty pages. This is because writeback code avoids writing inodes from superblock without backing device and blockdev_superblock is such a superblock. Since it's unexpected that sync doesn't writeout dirty data for block devices be nice to users and change the behavior to do so. So now we iterate over all block devices on blockdev_super instead of iterating over all superblocks when syncing block devices. Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Al Viro --- diff --git a/fs/sync.c b/fs/sync.c index 490e90201135..0b166f26362d 100644 --- a/fs/sync.c +++ b/fs/sync.c @@ -85,10 +85,14 @@ static void sync_fs_one_sb(struct super_block *sb, void *arg) sb->s_op->sync_fs(sb, *(int *)arg); } -static void sync_blkdev_one_sb(struct super_block *sb, void *arg) +static void flush_one_bdev(struct block_device *bdev, void *arg) { - if (!(sb->s_flags & MS_RDONLY)) - __sync_blockdev(sb->s_bdev, *(int *)arg); + __sync_blockdev(bdev, 0); +} + +static void sync_one_bdev(struct block_device *bdev, void *arg) +{ + sync_blockdev(bdev); } /* @@ -102,10 +106,10 @@ SYSCALL_DEFINE0(sync) wakeup_flusher_threads(0, WB_REASON_SYNC); iterate_supers(writeback_inodes_one_sb, NULL); iterate_supers(sync_fs_one_sb, &nowait); - iterate_supers(sync_blkdev_one_sb, &nowait); + iterate_bdevs(flush_one_bdev, NULL); iterate_supers(sync_inodes_one_sb, NULL); iterate_supers(sync_fs_one_sb, &wait); - iterate_supers(sync_blkdev_one_sb, &wait); + iterate_bdevs(sync_one_bdev, NULL); if (unlikely(laptop_mode)) laptop_sync_completion(); return 0; @@ -121,10 +125,10 @@ static void do_sync_work(struct work_struct *work) */ iterate_supers(sync_inodes_one_sb, &nowait); iterate_supers(sync_fs_one_sb, &nowait); - iterate_supers(sync_blkdev_one_sb, &nowait); + iterate_bdevs(flush_one_bdev, NULL); iterate_supers(sync_inodes_one_sb, &nowait); iterate_supers(sync_fs_one_sb, &nowait); - iterate_supers(sync_blkdev_one_sb, &nowait); + iterate_bdevs(flush_one_bdev, NULL); printk("Emergency Sync complete\n"); kfree(work); }