From: Lai Siyao <lai.siyao@intel.com>
Date: Wed, 7 Aug 2013 10:42:31 +0000 (+0800)
Subject: LU-3671 mdd: sync perm for dir and perm reduction only
X-Git-Tag: 2.4.92~39
X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=c0e6982b57319e5044cf12bee509c0c571a17cc5

LU-3671 mdd: sync perm for dir and perm reduction only

To mitigate performance impact for sync permission, do it for dir
and when permission is reduced only.

Remove extra sync permission check in mdd_xattr_set() because ACL
change is all handled in mdd_acl_set().

Signed-off-by: Lai Siyao <lai.siyao@intel.com>
Change-Id: I64fc720a380aafdaf858d83fbb85f29a1063e07f
Reviewed-on: http://review.whamcloud.com/7257
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
---

diff --git a/lustre/mdd/mdd_object.c b/lustre/mdd/mdd_object.c
index 824c92f..5d688cc 100644
--- a/lustre/mdd/mdd_object.c
+++ b/lustre/mdd/mdd_object.c
@@ -829,6 +829,13 @@ static int mdd_declare_attr_set(const struct lu_env *env,
 	return rc;
 }
 
+static inline bool permission_is_reduced(const struct lu_attr *old,
+					 const struct lu_attr *new)
+{
+	return ((new->la_mode & old->la_mode) & S_IRWXUGO) !=
+	       (old->la_mode & S_IRWXUGO);
+}
+
 /* set attr and LOV EA at once, return updated attr */
 int mdd_attr_set(const struct lu_env *env, struct md_object *obj,
 		 const struct md_attr *ma)
@@ -838,6 +845,7 @@ int mdd_attr_set(const struct lu_env *env, struct md_object *obj,
         struct thandle *handle;
         struct lu_attr *la_copy = &mdd_env_info(env)->mti_la_for_fix;
 	const struct lu_attr *la = &ma->ma_attr;
+	bool sync_perm = false;
 	int rc;
         ENTRY;
 
@@ -867,9 +875,38 @@ int mdd_attr_set(const struct lu_env *env, struct md_object *obj,
         if (rc)
                 GOTO(stop, rc);
 
-        /* permission changes may require sync operation */
-	if (ma->ma_attr.la_valid & (LA_MODE|LA_UID|LA_GID))
-                handle->th_sync |= !!mdd->mdd_sync_permission;
+	/*
+	 * LU-3671
+	 *
+	 * permission changes may require sync operation, to mitigate
+	 * performance impact, only do this for dir and when permission is
+	 * reduced.
+	 *
+	 * For regular files, version is updated with permission change
+	 * (see VBR), async permission won't cause any issue, while missing
+	 * permission change on directory may affect accessibility of other
+	 * objects.
+	 */
+	if (S_ISDIR(mdd_object_type(mdd_obj))) {
+		if (la->la_valid & (LA_UID | LA_GID)) {
+			sync_perm = true;
+		} else if (la->la_valid & LA_MODE &&
+			   la->la_mode & (S_ISUID | S_ISGID | S_ISVTX)) {
+			sync_perm = true;
+		} else if (la->la_valid & LA_MODE) {
+			struct lu_attr *tmp_la = &mdd_env_info(env)->mti_la;
+
+			rc = mdd_la_get(env, mdd_obj, tmp_la, BYPASS_CAPA);
+			if (rc)
+				GOTO(stop, rc);
+
+			if (permission_is_reduced(tmp_la, la))
+				sync_perm = true;
+		}
+	}
+
+	if (sync_perm)
+		handle->th_sync |= !!mdd->mdd_sync_permission;
 
 	if (la->la_valid & (LA_MTIME | LA_CTIME))
                 CDEBUG(D_INODE, "setting mtime "LPU64", ctime "LPU64"\n",
@@ -1045,10 +1082,6 @@ static int mdd_xattr_set(const struct lu_env *env, struct md_object *obj,
 	if (rc)
 		GOTO(stop, rc);
 
-	/* security-replated changes may require sync */
-	if (!strcmp(name, XATTR_NAME_ACL_ACCESS))
-		handle->th_sync |= !!mdd->mdd_sync_permission;
-
 	mdd_write_lock(env, mdd_obj, MOR_TGT_CHILD);
 
 	if (strncmp(XATTR_NAME_HSM, name, sizeof(XATTR_NAME_HSM) - 1) == 0) {
diff --git a/lustre/mdd/mdd_permission.c b/lustre/mdd/mdd_permission.c
index b18232e..f52d617 100644
--- a/lustre/mdd/mdd_permission.c
+++ b/lustre/mdd/mdd_permission.c
@@ -164,7 +164,8 @@ int mdd_acl_set(const struct lu_env *env, struct mdd_object *obj,
 				mdd_object_capa(env, obj));
 
 	/* security-replated changes may require sync */
-	handle->th_sync |= !!mdd->mdd_sync_permission;
+	if (S_ISDIR(mdd_object_type(obj)))
+		handle->th_sync |= !!mdd->mdd_sync_permission;
 unlock:
 	mdd_write_unlock(env, obj);
 stop: