Merge tag 'xfs-4.16-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Darrick Wong:
 "This merge cycle, we're again some substantive changes to XFS.

  Metadata verifiers have been restructured to provide more detail about
  which part of a metadata structure failed checks, and we've enhanced
  the new online fsck feature to cross-reference extent allocation
  information with the other metadata structures. With this pull, the
  metadata verification part of online fsck is more or less finished,
  though the feature is still experimental and still disabled by
  default.

  We're also preparing to remove the EXPERIMENTAL tag from a couple of
  features this cycle. This week we're committing a bunch of space
  accounting fixes for reflink and removing the EXPERIMENTAL tag from
  reflink; I anticipate that we'll be ready to do the same for the
  reverse mapping feature next week. (I don't have any pending fixes for
  rmap; however I wish to remove the tags one at a time.)

  This giant pile of patches has been run through a full xfstests run
  over the weekend and through a quick xfstests run against this
  morning's master, with no major failures reported. Let me know if
  there's any merge problems -- git merge reported that one of our
  patches touched the same function as the i_version series, but it
  resolved things cleanly.

  Summary:

   - Log faulting code locations when verifiers fail, for improved
     diagnosis of corrupt filesystems.

   - Implement metadata verifiers for local format inode fork data.

   - Online scrub now cross-references metadata records with other
     metadata.

   - Refactor the fs geometry ioctl generation functions.

   - Harden various metadata verifiers.

   - Fix various accounting problems.

   - Fix uncancelled transactions leaking when xattr functions fail.

   - Prevent the copy-on-write speculative preallocation garbage
     collector from racing with writeback.

   - Emit log reservation type information as trace data so that we can
     compare against xfsprogs.

   - Fix some erroneous asserts in the online scrub code.

   - Clean up the transaction reservation calculations.

   - Fix various minor bugs in online scrub.

   - Log complaints about mixed dio/buffered writes once per day and
     less noisily than before.

   - Refactor buffer log item lists to use list_head.

   - Break PNFS leases before reflinking blocks.

   - Reduce lock contention on reflink source files.

   - Fix some quota accounting problems with reflink.

   - Fix a serious corruption problem in the direct cow write code where
     we fed bad iomaps to the vfs iomap consumers.

   - Various other refactorings.

   - Remove EXPERIMENTAL tag from reflink!"

* tag 'xfs-4.16-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (94 commits)
  xfs: remove experimental tag for reflinks
  xfs: don't screw up direct writes when freesp is fragmented
  xfs: check reflink allocation mappings
  iomap: warn on zero-length mappings
  xfs: treat CoW fork operations as delalloc for quota accounting
  xfs: only grab shared inode locks for source file during reflink
  xfs: allow xfs_lock_two_inodes to take different EXCL/SHARED modes
  xfs: reflink should break pnfs leases before sharing blocks
  xfs: don't clobber inobt/finobt cursors when xref with rmap
  xfs: skip CoW writes past EOF when writeback races with truncate
  xfs: preserve i_rdev when recycling a reclaimable inode
  xfs: refactor accounting updates out of xfs_bmap_btalloc
  xfs: refactor inode verifier corruption error printing
  xfs: make tracepoint inode number format consistent
  xfs: always zero di_flags2 when we free the inode
  xfs: call xfs_qm_dqattach before performing reflink operations
  xfs: bmap code cleanup
  Use list_head infra-structure for buffer's log items list
  Split buffer's b_fspriv field
  Get rid of xfs_buf_log_item_t typedef
  ...

1 files changed, 49 insertions, 21 deletions

diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 3bcb8fd2a826..d53a316162d6 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -296,6 +296,7 @@ xfs_reinit_inode(
 	uint32_t	generation = inode->i_generation;
 	uint64_t	version = inode_peek_iversion(inode);
 	umode_t		mode = inode->i_mode;
+	dev_t		dev = inode->i_rdev;
 
 	error = inode_init_always(mp->m_super, inode);
 
@@ -303,6 +304,7 @@ xfs_reinit_inode(
 	inode->i_generation = generation;
 	inode_set_iversion_queried(inode, version);
 	inode->i_mode = mode;
+	inode->i_rdev = dev;
 	return error;
 }
 
@@ -474,6 +476,11 @@ xfs_iget_cache_miss(
 	if (error)
 		goto out_destroy;
 
+	if (!xfs_inode_verify_forks(ip)) {
+		error = -EFSCORRUPTED;
+		goto out_destroy;
+	}
+
 	trace_xfs_iget_miss(ip);
 
 	if ((VFS_I(ip)->i_mode == 0) && !(flags & XFS_IGET_CREATE)) {
@@ -1651,28 +1658,15 @@ xfs_inode_clear_eofblocks_tag(
 }
 
 /*
- * Automatic CoW Reservation Freeing
- *
- * These functions automatically garbage collect leftover CoW reservations
- * that were made on behalf of a cowextsize hint when we start to run out
- * of quota or when the reservations sit around for too long.  If the file
- * has dirty pages or is undergoing writeback, its CoW reservations will
- * be retained.
- *
- * The actual garbage collection piggybacks off the same code that runs
- * the speculative EOF preallocation garbage collector.
+ * Set ourselves up to free CoW blocks from this file.  If it's already clean
+ * then we can bail out quickly, but otherwise we must back off if the file
+ * is undergoing some kind of write.
  */
-STATIC int
-xfs_inode_free_cowblocks(
+static bool
+xfs_prep_free_cowblocks(
 	struct xfs_inode	*ip,
-	int			flags,
-	void			*args)
+	struct xfs_ifork	*ifp)
 {
-	int ret;
-	struct xfs_eofblocks *eofb = args;
-	int match;
-	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
-
 	/*
 	 * Just clear the tag if we have an empty cow fork or none at all. It's
 	 * possible the inode was fully unshared since it was originally tagged.
@@ -1680,7 +1674,7 @@ xfs_inode_free_cowblocks(
 	if (!xfs_is_reflink_inode(ip) || !ifp->if_bytes) {
 		trace_xfs_inode_free_cowblocks_invalid(ip);
 		xfs_inode_clear_cowblocks_tag(ip);
-		return 0;
+		return false;
 	}
 
 	/*
@@ -1691,6 +1685,35 @@ xfs_inode_free_cowblocks(
 	    mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_DIRTY) ||
 	    mapping_tagged(VFS_I(ip)->i_mapping, PAGECACHE_TAG_WRITEBACK) ||
 	    atomic_read(&VFS_I(ip)->i_dio_count))
+		return false;
+
+	return true;
+}
+
+/*
+ * Automatic CoW Reservation Freeing
+ *
+ * These functions automatically garbage collect leftover CoW reservations
+ * that were made on behalf of a cowextsize hint when we start to run out
+ * of quota or when the reservations sit around for too long.  If the file
+ * has dirty pages or is undergoing writeback, its CoW reservations will
+ * be retained.
+ *
+ * The actual garbage collection piggybacks off the same code that runs
+ * the speculative EOF preallocation garbage collector.
+ */
+STATIC int
+xfs_inode_free_cowblocks(
+	struct xfs_inode	*ip,
+	int			flags,
+	void			*args)
+{
+	struct xfs_eofblocks	*eofb = args;
+	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
+	int			match;
+	int			ret = 0;
+
+	if (!xfs_prep_free_cowblocks(ip, ifp))
 		return 0;
 
 	if (eofb) {
@@ -1711,7 +1734,12 @@ xfs_inode_free_cowblocks(
 	xfs_ilock(ip, XFS_IOLOCK_EXCL);
 	xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
 
-	ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
+	/*
+	 * Check again, nobody else should be able to dirty blocks or change
+	 * the reflink iflag now that we have the first two locks held.
+	 */
+	if (xfs_prep_free_cowblocks(ip, ifp))
+		ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
 
 	xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
 	xfs_iunlock(ip, XFS_IOLOCK_EXCL);