Merge tag 'for-5.16/inode-sync-2021-10-29' of git://git.kernel.dk/linux-block

Pull block inode sync updates from Jens Axboe:
 "This contains improvements to how bdev inode syncing is handled,
  unifying the API"

* tag 'for-5.16/inode-sync-2021-10-29' of git://git.kernel.dk/linux-block:
  block: simplify the block device syncing code
  ntfs3: use sync_blockdev_nowait
  fat: use sync_blockdev_nowait
  btrfs: use sync_blockdev
  xen-blkback: use sync_blockdev
  block: remove __sync_blockdev
  fs: remove __sync_filesystem

5 files changed, 26 insertions, 57 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 676c7c4e6e59..9533f358850e 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -508,7 +508,7 @@ btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
 	}
 
 	if (flush)
-		filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
+		sync_blockdev(*bdev);
 	ret = set_blocksize(*bdev, BTRFS_BDEV_BLOCKSIZE);
 	if (ret) {
 		blkdev_put(*bdev, flags);
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 9f3cd03668ad..a6f1c6d426d1 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -1940,10 +1940,8 @@ int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2)
 		ret = writeback_inode(i1);
 	if (!ret && i2)
 		ret = writeback_inode(i2);
-	if (!ret) {
-		struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
-		ret = filemap_flush(mapping);
-	}
+	if (!ret)
+		ret = sync_blockdev_nowait(sb->s_bdev);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(fat_flush_inodes);
diff --git a/fs/internal.h b/fs/internal.h
index 3cd065c8a66b..cdd83d4899bb 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -23,22 +23,11 @@ struct pipe_inode_info;
 #ifdef CONFIG_BLOCK
 extern void __init bdev_cache_init(void);
 
-extern int __sync_blockdev(struct block_device *bdev, int wait);
-void iterate_bdevs(void (*)(struct block_device *, void *), void *);
 void emergency_thaw_bdev(struct super_block *sb);
 #else
 static inline void bdev_cache_init(void)
 {
 }
-
-static inline int __sync_blockdev(struct block_device *bdev, int wait)
-{
-	return 0;
-}
-static inline void iterate_bdevs(void (*f)(struct block_device *, void *),
-		void *arg)
-{
-}
 static inline int emergency_thaw_bdev(struct super_block *sb)
 {
 	return 0;
diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c
index 859951d785cb..a87ab3ad3cd3 100644
--- a/fs/ntfs3/inode.c
+++ b/fs/ntfs3/inode.c
@@ -1046,7 +1046,7 @@ int ntfs_flush_inodes(struct super_block *sb, struct inode *i1,
 	if (!ret && i2)
 		ret = writeback_inode(i2);
 	if (!ret)
-		ret = filemap_flush(sb->s_bdev->bd_inode->i_mapping);
+		ret = sync_blockdev_nowait(sb->s_bdev);
 	return ret;
 }
 
diff --git a/fs/sync.c b/fs/sync.c
index 1373a610dc78..3ce8e2137f31 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -3,6 +3,7 @@
  * High-level sync()-related operations
  */
 
+#include <linux/blkdev.h>
 #include <linux/kernel.h>
 #include <linux/file.h>
 #include <linux/fs.h>
@@ -22,25 +23,6 @@
 			SYNC_FILE_RANGE_WAIT_AFTER)
 
 /*
- * Do the filesystem syncing work. For simple filesystems
- * writeback_inodes_sb(sb) just dirties buffers with inodes so we have to
- * submit IO for these buffers via __sync_blockdev(). This also speeds up the
- * wait == 1 case since in that case write_inode() functions do
- * sync_dirty_buffer() and thus effectively write one block at a time.
- */
-static int __sync_filesystem(struct super_block *sb, int wait)
-{
-	if (wait)
-		sync_inodes_sb(sb);
-	else
-		writeback_inodes_sb(sb, WB_REASON_SYNC);
-
-	if (sb->s_op->sync_fs)
-		sb->s_op->sync_fs(sb, wait);
-	return __sync_blockdev(sb->s_bdev, wait);
-}
-
-/*
  * Write out and wait upon all dirty data associated with this
  * superblock.  Filesystem data as well as the underlying block
  * device.  Takes the superblock lock.
@@ -61,10 +43,25 @@ int sync_filesystem(struct super_block *sb)
 	if (sb_rdonly(sb))
 		return 0;
 
-	ret = __sync_filesystem(sb, 0);
+	/*
+	 * Do the filesystem syncing work.  For simple filesystems
+	 * writeback_inodes_sb(sb) just dirties buffers with inodes so we have
+	 * to submit I/O for these buffers via sync_blockdev().  This also
+	 * speeds up the wait == 1 case since in that case write_inode()
+	 * methods call sync_dirty_buffer() and thus effectively write one block
+	 * at a time.
+	 */
+	writeback_inodes_sb(sb, WB_REASON_SYNC);
+	if (sb->s_op->sync_fs)
+		sb->s_op->sync_fs(sb, 0);
+	ret = sync_blockdev_nowait(sb->s_bdev);
 	if (ret < 0)
 		return ret;
-	return __sync_filesystem(sb, 1);
+
+	sync_inodes_sb(sb);
+	if (sb->s_op->sync_fs)
+		sb->s_op->sync_fs(sb, 1);
+	return sync_blockdev(sb->s_bdev);
 }
 EXPORT_SYMBOL(sync_filesystem);
 
@@ -81,21 +78,6 @@ static void sync_fs_one_sb(struct super_block *sb, void *arg)
 		sb->s_op->sync_fs(sb, *(int *)arg);
 }
 
-static void fdatawrite_one_bdev(struct block_device *bdev, void *arg)
-{
-	filemap_fdatawrite(bdev->bd_inode->i_mapping);
-}
-
-static void fdatawait_one_bdev(struct block_device *bdev, void *arg)
-{
-	/*
-	 * We keep the error status of individual mapping so that
-	 * applications can catch the writeback error using fsync(2).
-	 * See filemap_fdatawait_keep_errors() for details.
-	 */
-	filemap_fdatawait_keep_errors(bdev->bd_inode->i_mapping);
-}
-
 /*
  * Sync everything. We start by waking flusher threads so that most of
  * writeback runs on all devices in parallel. Then we sync all inodes reliably
@@ -114,8 +96,8 @@ void ksys_sync(void)
 	iterate_supers(sync_inodes_one_sb, NULL);
 	iterate_supers(sync_fs_one_sb, &nowait);
 	iterate_supers(sync_fs_one_sb, &wait);
-	iterate_bdevs(fdatawrite_one_bdev, NULL);
-	iterate_bdevs(fdatawait_one_bdev, NULL);
+	sync_bdevs(false);
+	sync_bdevs(true);
 	if (unlikely(laptop_mode))
 		laptop_sync_completion();
 }
@@ -136,10 +118,10 @@ static void do_sync_work(struct work_struct *work)
 	 */
 	iterate_supers(sync_inodes_one_sb, &nowait);
 	iterate_supers(sync_fs_one_sb, &nowait);
-	iterate_bdevs(fdatawrite_one_bdev, NULL);
+	sync_bdevs(false);
 	iterate_supers(sync_inodes_one_sb, &nowait);
 	iterate_supers(sync_fs_one_sb, &nowait);
-	iterate_bdevs(fdatawrite_one_bdev, NULL);
+	sync_bdevs(false);
 	printk("Emergency Sync complete\n");
 	kfree(work);
 }