Merge tag 'xfs-for-linus-3.16-rc1' of git://oss.sgi.com/xfs/xfs

Pull xfs updates from Dave Chinner:
 "This update contains:
   - cleanup removing unused function args
   - rework of the filestreams allocator to use dentry cache parent
     lookups
   - new on-disk free inode btree and optimised inode allocator
   - various bug fixes
   - rework of internal attribute API
   - cleanup of superblock feature bit support to remove historic cruft
   - more fixes and minor cleanups
   - added a new directory/attribute geometry abstraction
   - yet more fixes and minor cleanups"

* tag 'xfs-for-linus-3.16-rc1' of git://oss.sgi.com/xfs/xfs: (86 commits)
  xfs: fix xfs_da_args sparse warning in xfs_readdir
  xfs: Fix rounding in xfs_alloc_fix_len()
  xfs: tone down writepage/releasepage WARN_ONs
  xfs: small cleanup in xfs_lowbit64()
  xfs: kill xfs_buf_geterror()
  xfs: xfs_readsb needs to check for magic numbers
  xfs: block allocation work needs to be kswapd aware
  xfs: remove redundant geometry information from xfs_da_state
  xfs: replace attr LBSIZE with xfs_da_geometry
  xfs: pass xfs_da_args to xfs_attr_leaf_newentsize
  xfs: use xfs_da_geometry for block size in attr code
  xfs: remove mp->m_dir_geo from directory logging
  xfs: reduce direct usage of mp->m_dir_geo
  xfs: move node entry counts to xfs_da_geometry
  xfs: convert dir/attr btree threshold to xfs_da_geometry
  xfs: convert m_dirblksize to xfs_da_geometry
  xfs: convert m_dirblkfsbs to xfs_da_geometry
  xfs: convert directory segment limits to xfs_da_geometry
  xfs: convert directory db conversion to xfs_da_geometry
  xfs: convert directory dablk conversion to xfs_da_geometry
  ...

1 files changed, 13 insertions, 6 deletions

diff --git a/fs/xfs/xfs_log.h b/fs/xfs/xfs_log.h
index 2c4004475e71..84e0deb95abd 100644
--- a/fs/xfs/xfs_log.h
+++ b/fs/xfs/xfs_log.h
@@ -24,7 +24,8 @@ struct xfs_log_vec {
 	struct xfs_log_iovec	*lv_iovecp;	/* iovec array */
 	struct xfs_log_item	*lv_item;	/* owner */
 	char			*lv_buf;	/* formatted buffer */
-	int			lv_buf_len;	/* size of formatted buffer */
+	int			lv_bytes;	/* accounted space in buffer */
+	int			lv_buf_len;	/* aligned size of buffer */
 	int			lv_size;	/* size of allocated lv */
 };
 
@@ -52,15 +53,21 @@ xlog_prepare_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
 	return vec->i_addr;
 }
 
+/*
+ * We need to make sure the next buffer is naturally aligned for the biggest
+ * basic data type we put into it.  We already accounted for this padding when
+ * sizing the buffer.
+ *
+ * However, this padding does not get written into the log, and hence we have to
+ * track the space used by the log vectors separately to prevent log space hangs
+ * due to inaccurate accounting (i.e. a leak) of the used log space through the
+ * CIL context ticket.
+ */
 static inline void
 xlog_finish_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec *vec, int len)
 {
-	/*
-	 * We need to make sure the next buffer is naturally aligned for the
-	 * biggest basic data type we put into it.  We already accounted for
-	 * this when sizing the buffer.
-	 */
 	lv->lv_buf_len += round_up(len, sizeof(uint64_t));
+	lv->lv_bytes += len;
 	vec->i_len = len;
 }