[XFS] Use PFLAGS_RESTORE_FSTRANS in place of PFLAGS_RESTORE, only restore

previously saved FSTRANS state.  Otherwise we can lose process flags.

SGI Modid: xfs-linux:xfs-kern:168082a

fs/xfs/linux/kmem.h

@@ -57,13 +57,21 @@ typedef unsigned long xfs_pflags_t;
 
 #define PFLAGS_TEST_FSTRANS()           (current->flags & PF_FSTRANS)
 
+/* these could be nested, so we save state */
 #define PFLAGS_SET_FSTRANS(STATEP) do {	\
 	*(STATEP) = current->flags;	\
 	current->flags |= PF_FSTRANS;	\
 } while (0)
 
-#define PFLAGS_RESTORE(STATEP) do {	\
-	current->flags = *(STATEP);	\
+#define PFLAGS_CLEAR_FSTRANS(STATEP) do { \
+	*(STATEP) = current->flags;	\
+	current->flags &= ~PF_FSTRANS;	\
+} while (0)
+
+/* Restore the PF_FSTRANS state to what was saved in STATEP */
+#define PFLAGS_RESTORE_FSTRANS(STATEP) do {     		\
+	current->flags = ((current->flags & ~PF_FSTRANS) |	\
+			  (*(STATEP) & PF_FSTRANS));		\
 } while (0)
 
 #define PFLAGS_DUP(OSTATEP, NSTATEP) do { \

fs/xfs/xfs_trans.c

@@ -250,7 +250,7 @@ xfs_trans_reserve(
 		error = xfs_mod_incore_sb(tp->t_mountp, XFS_SBS_FDBLOCKS,
 					  -blocks, rsvd);
 		if (error != 0) {
-                        PFLAGS_RESTORE(&tp->t_pflags);
+                        PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
 			return (XFS_ERROR(ENOSPC));
 		}
 		tp->t_blk_res += blocks;
@@ -323,7 +323,7 @@ xfs_trans_reserve(
 		tp->t_blk_res = 0;
 	}
 
-        PFLAGS_RESTORE(&tp->t_pflags);
+        PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
 
 	return (error);
 }
@@ -734,7 +734,7 @@ xfs_trans_commit(
 			if (commit_lsn == -1 && !shutdown)
 				shutdown = XFS_ERROR(EIO);
 		}
-                PFLAGS_RESTORE(&tp->t_pflags);
+                PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
 		xfs_trans_free_items(tp, shutdown? XFS_TRANS_ABORT : 0);
 		xfs_trans_free_busy(tp);
 		xfs_trans_free(tp);
@@ -823,7 +823,7 @@ xfs_trans_commit(
 	 * had pinned, clean up, free trans structure, and return error.
 	 */
 	if (error || commit_lsn == -1) {
-                PFLAGS_RESTORE(&tp->t_pflags);
+                PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
 		xfs_trans_uncommit(tp, flags|XFS_TRANS_ABORT);
 		return XFS_ERROR(EIO);
 	}
@@ -862,7 +862,7 @@ xfs_trans_commit(
 	error = xfs_log_notify(mp, commit_iclog, &(tp->t_logcb));
 
 	/* mark this thread as no longer being in a transaction */
-        PFLAGS_RESTORE(&tp->t_pflags);
+        PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
 
 	/*
 	 * Once all the items of the transaction have been copied
@@ -1100,7 +1100,7 @@ xfs_trans_cancel(
 	}
 
 	/* mark this thread as no longer being in a transaction */
-        PFLAGS_RESTORE(&tp->t_pflags);
+        PFLAGS_RESTORE_FSTRANS(&tp->t_pflags);
 
 	xfs_trans_free_items(tp, flags);
 	xfs_trans_free_busy(tp);