1 files changed, 100 insertions, 35 deletions

diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 34227115a5d6..9a18f69f6e96 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -37,6 +37,7 @@
 
 #include <linux/kthread.h>
 #include <linux/freezer.h>
+#include <linux/iversion.h>
 
 /*
  * Allocate and initialise an xfs_inode.
@@ -293,15 +294,17 @@ xfs_reinit_inode(
 	int		error;
 	uint32_t	nlink = inode->i_nlink;
 	uint32_t	generation = inode->i_generation;
-	uint64_t	version = inode->i_version;
+	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);
 
 	set_nlink(inode, nlink);
 	inode->i_generation = generation;
-	inode->i_version = version;
+	inode_set_iversion_queried(inode, version);
 	inode->i_mode = mode;
+	inode->i_rdev = dev;
 	return error;
 }
 
@@ -473,9 +476,35 @@ 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)) {
+
+	/*
+	 * If we are allocating a new inode, then check what was returned is
+	 * actually a free, empty inode. If we are not allocating an inode,
+	 * the check we didn't find a free inode.
+	 */
+	if (flags & XFS_IGET_CREATE) {
+		if (VFS_I(ip)->i_mode != 0) {
+			xfs_warn(mp,
+"Corruption detected! Free inode 0x%llx not marked free on disk",
+				ino);
+			error = -EFSCORRUPTED;
+			goto out_destroy;
+		}
+		if (ip->i_d.di_nblocks != 0) {
+			xfs_warn(mp,
+"Corruption detected! Free inode 0x%llx has blocks allocated!",
+				ino);
+			error = -EFSCORRUPTED;
+			goto out_destroy;
+		}
+	} else if (VFS_I(ip)->i_mode == 0) {
 		error = -ENOENT;
 		goto out_destroy;
 	}
@@ -610,7 +639,7 @@ again:
 	} else {
 		rcu_read_unlock();
 		if (flags & XFS_IGET_INCORE) {
-			error = -ENOENT;
+			error = -ENODATA;
 			goto out_error_or_again;
 		}
 		XFS_STATS_INC(mp, xs_ig_missed);
@@ -870,7 +899,7 @@ xfs_eofblocks_worker(
  * based on the 'speculative_cow_prealloc_lifetime' tunable (5m by default).
  * (We'll just piggyback on the post-EOF prealloc space workqueue.)
  */
-STATIC void
+void
 xfs_queue_cowblocks(
 	struct xfs_mount *mp)
 {
@@ -1536,8 +1565,23 @@ xfs_inode_free_quota_eofblocks(
 	return __xfs_inode_free_quota_eofblocks(ip, xfs_icache_free_eofblocks);
 }
 
+static inline unsigned long
+xfs_iflag_for_tag(
+	int		tag)
+{
+	switch (tag) {
+	case XFS_ICI_EOFBLOCKS_TAG:
+		return XFS_IEOFBLOCKS;
+	case XFS_ICI_COWBLOCKS_TAG:
+		return XFS_ICOWBLOCKS;
+	default:
+		ASSERT(0);
+		return 0;
+	}
+}
+
 static void
-__xfs_inode_set_eofblocks_tag(
+__xfs_inode_set_blocks_tag(
 	xfs_inode_t	*ip,
 	void		(*execute)(struct xfs_mount *mp),
 	void		(*set_tp)(struct xfs_mount *mp, xfs_agnumber_t agno,
@@ -1552,10 +1596,10 @@ __xfs_inode_set_eofblocks_tag(
 	 * Don't bother locking the AG and looking up in the radix trees
 	 * if we already know that we have the tag set.
 	 */
-	if (ip->i_flags & XFS_IEOFBLOCKS)
+	if (ip->i_flags & xfs_iflag_for_tag(tag))
 		return;
 	spin_lock(&ip->i_flags_lock);
-	ip->i_flags |= XFS_IEOFBLOCKS;
+	ip->i_flags |= xfs_iflag_for_tag(tag);
 	spin_unlock(&ip->i_flags_lock);
 
 	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
@@ -1587,13 +1631,13 @@ xfs_inode_set_eofblocks_tag(
 	xfs_inode_t	*ip)
 {
 	trace_xfs_inode_set_eofblocks_tag(ip);
-	return __xfs_inode_set_eofblocks_tag(ip, xfs_queue_eofblocks,
+	return __xfs_inode_set_blocks_tag(ip, xfs_queue_eofblocks,
 			trace_xfs_perag_set_eofblocks,
 			XFS_ICI_EOFBLOCKS_TAG);
 }
 
 static void
-__xfs_inode_clear_eofblocks_tag(
+__xfs_inode_clear_blocks_tag(
 	xfs_inode_t	*ip,
 	void		(*clear_tp)(struct xfs_mount *mp, xfs_agnumber_t agno,
 				    int error, unsigned long caller_ip),
@@ -1603,7 +1647,7 @@ __xfs_inode_clear_eofblocks_tag(
 	struct xfs_perag *pag;
 
 	spin_lock(&ip->i_flags_lock);
-	ip->i_flags &= ~XFS_IEOFBLOCKS;
+	ip->i_flags &= ~xfs_iflag_for_tag(tag);
 	spin_unlock(&ip->i_flags_lock);
 
 	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
@@ -1630,33 +1674,20 @@ xfs_inode_clear_eofblocks_tag(
 	xfs_inode_t	*ip)
 {
 	trace_xfs_inode_clear_eofblocks_tag(ip);
-	return __xfs_inode_clear_eofblocks_tag(ip,
+	return __xfs_inode_clear_blocks_tag(ip,
 			trace_xfs_perag_clear_eofblocks, XFS_ICI_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.
@@ -1664,7 +1695,7 @@ 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;
 	}
 
 	/*
@@ -1675,6 +1706,35 @@ 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) {
@@ -1695,7 +1755,12 @@ 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);
@@ -1724,7 +1789,7 @@ xfs_inode_set_cowblocks_tag(
 	xfs_inode_t	*ip)
 {
 	trace_xfs_inode_set_cowblocks_tag(ip);
-	return __xfs_inode_set_eofblocks_tag(ip, xfs_queue_cowblocks,
+	return __xfs_inode_set_blocks_tag(ip, xfs_queue_cowblocks,
 			trace_xfs_perag_set_cowblocks,
 			XFS_ICI_COWBLOCKS_TAG);
 }
@@ -1734,6 +1799,6 @@ xfs_inode_clear_cowblocks_tag(
 	xfs_inode_t	*ip)
 {
 	trace_xfs_inode_clear_cowblocks_tag(ip);
-	return __xfs_inode_clear_eofblocks_tag(ip,
+	return __xfs_inode_clear_blocks_tag(ip,
 			trace_xfs_perag_clear_cowblocks, XFS_ICI_COWBLOCKS_TAG);
 }