Patch "Btrfs: fix unexpected -EEXIST when creating new inode" has been added to the 4.15-stable tree

This is a note to let you know that I've just added the patch titled

Btrfs: fix unexpected -EEXIST when creating new inode

to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
btrfs-fix-unexpected-eexist-when-creating-new-inode.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Liu Bo <[email protected]>
Date: Thu, 25 Jan 2018 11:02:56 -0700
Subject: Btrfs: fix unexpected -EEXIST when creating new inode

From: Liu Bo <[email protected]>

commit 900c9981680067573671ecc5cbfa7c5770be3a40 upstream.

The highest objectid, which is assigned to new inode, is decided at the time of initializing fs roots. However, in cases where log replay gets processed, the btree which fs root owns might be changed, so we have to search it again for the highest objectid, otherwise creating new inode would end up with -EEXIST.

---
 fs/btrfs/tree-log.c |   18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

@@ -28,6 +28,7 @@
 #include "hash.h"
 #include "compression.h"
 #include "qgroup.h"
+#include "inode-map.h"
 
 /* magic values for the inode_only field in btrfs_log_inode:
  *

@@ -5715,6 +5716,23 @@ again:
 						      path);
 		}
 
+		if (!ret && wc.stage == LOG_WALK_REPLAY_ALL) {
+			struct btrfs_root *root = wc.replay_dest;
+
+			btrfs_release_path(path);
+
+			/*
+			 * We have just replayed everything, and the highest
+			 * objectid of fs roots probably has changed in case
+			 * some inode_item's got replayed.
+			 *
+			 * root->objectid_mutex is not acquired as log replay
+			 * could only happen during mount.
+			 */
+			ret = btrfs_find_highest_objectid(root,
+						  &root->highest_objectid);
+		}
+
 		key.offset = found_key.offset - 1;
 		wc.replay_dest->log_root = NULL;
 		free_extent_buffer(log->node);

Patches currently in stable-queue which might be from [email protected] are

queue-4.15/btrfs-fix-btrfs_evict_inode-to-handle-abnormal-inodes-correctly.patch queue-4.15/btrfs-fix-crash-due-to-not-cleaning-up-tree-log-block-s-dirty-bits.patch queue-4.15/btrfs-fix-use-after-free-on-root-orphan_block_rsv.patch queue-4.15/btrfs-fix-extent-state-leak-from-tree-log.patch queue-4.15/btrfs-fix-unexpected-eexist-when-creating-new-inode.patch queue-4.15/btrfs-fix-deadlock-in-run_delalloc_nocow.patch