From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 28 Nov 2018 16:38:20 +0000 (-0800)
Subject: Merge tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave... 
X-Git-Tag: v4.20-rc5~37
X-Git-Url: http://git.samba.org/samba.git/?p=sfrench%2Fcifs-2.6.git;a=commitdiff_plain;h=121b018f8c74b4e0ba81b4b8ee73a82db3f24b7b;hp=-c

Merge tag 'for-4.20-rc4-tag' of git://git./linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Some of these bugs are being hit during testing so we'd like to get
  them merged, otherwise there are usual stability fixes for stable
  trees"

* tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: relocation: set trans to be NULL after ending transaction
  Btrfs: fix race between enabling quotas and subvolume creation
  Btrfs: send, fix infinite loop due to directory rename dependencies
  Btrfs: ensure path name is null terminated at btrfs_control_ioctl
  Btrfs: fix rare chances for data loss when doing a fast fsync
  btrfs: Always try all copies when reading extent buffers
---

121b018f8c74b4e0ba81b4b8ee73a82db3f24b7b
diff --combined fs/btrfs/file.c
index a3c22e16509b,b92b7f05c3d5..58e93bce3036
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@@ -2088,6 -2088,30 +2088,30 @@@ int btrfs_sync_file(struct file *file, 
  
  	atomic_inc(&root->log_batch);
  
+ 	/*
+ 	 * Before we acquired the inode's lock, someone may have dirtied more
+ 	 * pages in the target range. We need to make sure that writeback for
+ 	 * any such pages does not start while we are logging the inode, because
+ 	 * if it does, any of the following might happen when we are not doing a
+ 	 * full inode sync:
+ 	 *
+ 	 * 1) We log an extent after its writeback finishes but before its
+ 	 *    checksums are added to the csum tree, leading to -EIO errors
+ 	 *    when attempting to read the extent after a log replay.
+ 	 *
+ 	 * 2) We can end up logging an extent before its writeback finishes.
+ 	 *    Therefore after the log replay we will have a file extent item
+ 	 *    pointing to an unwritten extent (and no data checksums as well).
+ 	 *
+ 	 * So trigger writeback for any eventual new dirty pages and then we
+ 	 * wait for all ordered extents to complete below.
+ 	 */
+ 	ret = start_ordered_ops(inode, start, end);
+ 	if (ret) {
+ 		inode_unlock(inode);
+ 		goto out;
+ 	}
+ 
  	/*
  	 * We have to do this here to avoid the priority inversion of waiting on
  	 * IO of a lower priority task while holding a transaciton open.
@@@ -3298,7 -3322,8 +3322,7 @@@ const struct file_operations btrfs_file
  #ifdef CONFIG_COMPAT
  	.compat_ioctl	= btrfs_compat_ioctl,
  #endif
 -	.clone_file_range = btrfs_clone_file_range,
 -	.dedupe_file_range = btrfs_dedupe_file_range,
 +	.remap_file_range = btrfs_remap_file_range,
  };
  
  void __cold btrfs_auto_defrag_exit(void)