xfs: use an XFS_OPSTATE_ flag for detecting if logged xattrs are available

Per reviewer request, use an OPSTATE flag (+ helpers) to decide if
logged xattrs are enabled, instead of querying the xfs_sb.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/xfs_attr_item.c

@@ -469,7 +469,7 @@ xfs_attri_validate(
 	unsigned int			op = attrp->alfi_op_flags &
 					     XFS_ATTRI_OP_FLAGS_TYPE_MASK;
 
-	if (!xfs_sb_version_haslogxattrs(&mp->m_sb))
+	if (!xfs_is_using_logged_xattrs(mp))
 		return false;
 
 	if (attrp->__pad != 0)

fs/xfs/xfs_mount.c

@@ -231,6 +231,13 @@ xfs_readsb(
 	mp->m_features |= xfs_sb_version_to_features(sbp);
 	xfs_reinit_percpu_counters(mp);
 
+	/*
+	 * If logged xattrs are enabled after log recovery finishes, then set
+	 * the opstate so that log recovery will work properly.
+	 */
+	if (xfs_sb_version_haslogxattrs(&mp->m_sb))
+		xfs_set_using_logged_xattrs(mp);
+
 	/* no need to be quiet anymore, so reset the buf ops */
 	bp->b_ops = &xfs_sb_buf_ops;
 
@@ -829,6 +836,15 @@ xfs_mountfs(
 		goto out_inodegc_shrinker;
 	}
 
+	/*
+	 * If logged xattrs are still enabled after log recovery finishes, then
+	 * they'll be available until unmount.  Otherwise, turn them off.
+	 */
+	if (xfs_sb_version_haslogxattrs(&mp->m_sb))
+		xfs_set_using_logged_xattrs(mp);
+	else
+		xfs_clear_using_logged_xattrs(mp);
+
 	/* Enable background inode inactivation workers. */
 	xfs_inodegc_start(mp);
 	xfs_blockgc_start(mp);

fs/xfs/xfs_mount.h

@@ -444,6 +444,8 @@ __XFS_HAS_FEAT(nouuid, NOUUID)
 #define XFS_OPSTATE_QUOTACHECK_RUNNING	10
 /* Do we want to clear log incompat flags? */
 #define XFS_OPSTATE_UNSET_LOG_INCOMPAT	11
+/* Filesystem can use logged extended attributes */
+#define XFS_OPSTATE_USE_LARP		12
 
 #define __XFS_IS_OPSTATE(name, NAME) \
 static inline bool xfs_is_ ## name (struct xfs_mount *mp) \
@@ -472,6 +474,7 @@ __XFS_IS_OPSTATE(quotacheck_running, QUOTACHECK_RUNNING)
 # define xfs_is_quotacheck_running(mp)	(false)
 #endif
 __XFS_IS_OPSTATE(done_with_log_incompat, UNSET_LOG_INCOMPAT)
+__XFS_IS_OPSTATE(using_logged_xattrs, USE_LARP)
 
 static inline bool
 xfs_should_warn(struct xfs_mount *mp, long nr)
@@ -491,7 +494,8 @@ xfs_should_warn(struct xfs_mount *mp, long nr)
 	{ (1UL << XFS_OPSTATE_WARNED_SHRINK),		"wshrink" }, \
 	{ (1UL << XFS_OPSTATE_WARNED_LARP),		"wlarp" }, \
 	{ (1UL << XFS_OPSTATE_QUOTACHECK_RUNNING),	"quotacheck" }, \
-	{ (1UL << XFS_OPSTATE_UNSET_LOG_INCOMPAT),	"unset_log_incompat" }
+	{ (1UL << XFS_OPSTATE_UNSET_LOG_INCOMPAT),	"unset_log_incompat" }, \
+	{ (1UL << XFS_OPSTATE_USE_LARP),		"logged_xattrs" }
 
 /*
  * Max and min values for mount-option defined I/O

fs/xfs/xfs_xattr.c

@@ -31,7 +31,7 @@ xfs_attr_grab_log_assist(
 	int			error = 0;
 
 	/* xattr update log intent items are already enabled */
-	if (xfs_sb_version_haslogxattrs(&mp->m_sb))
+	if (xfs_is_using_logged_xattrs(mp))
 		return 0;
 
 	/*
@@ -48,6 +48,7 @@ xfs_attr_grab_log_assist(
 			XFS_SB_FEAT_INCOMPAT_LOG_XATTRS);
 	if (error)
 		return error;
+	xfs_set_using_logged_xattrs(mp);
 
 	xfs_warn_mount(mp, XFS_OPSTATE_WARNED_LARP,
  "EXPERIMENTAL logged extended attributes feature in use. Use at your own risk!");