lvresize: fix zero size extension

Commit ca878a3426197b629c76e98cfc049948da470cd7 changed behavior
or resize operation. Later the code has been futher changed
to skip fs resize completely when size of LV is already matching
and finaly at the most recent resize changeset for resize the
check for matching size has been eliminated as well so we ended
with a request call to resize fs to 0 size in some cases.

This commit reoders some test so the prompt happens just once before
resize of possibly 2 related volumes.

Also extra test for having LV already given size is added, and
whole metadata update is skipped for this case as the only
result would be an increment of seqno.

However the filesystem is still resized when requested,
so if the LV has some size and the resize is resolved to
the same size, the filesystem resize is called so in case FS
would not match, the resize will happen.

3 files changed, 53 insertions, 37 deletions

diff --git a/WHATS_NEW b/WHATS_NEW
index 5653b139c..3ed398c98 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
 Version 2.02.161 - 
 ================================
+  Fix lvresize of filesystem when LV has already right size (2.02.141).
   New LVM_LOG_FILE_MAX_LINES env var to limit max size of created logs.
 
 Version 2.02.160 - 6th July 2016
diff --git a/lib/metadata/lv_manip.c b/lib/metadata/lv_manip.c
index d11b1259f..022bb1f9d 100644
--- a/lib/metadata/lv_manip.c
+++ b/lib/metadata/lv_manip.c
@@ -5130,38 +5130,8 @@ static int _lvresize_volume(struct logical_volume *lv,
 	struct volume_group *vg = lv->vg;
 	struct cmd_context *cmd = vg->cmd;
 	uint32_t old_extents;
-	int status;
 	alloc_policy_t alloc = lp->alloc ? : lv->alloc;
 
-	if ((lp->resize == LV_REDUCE) && (pvh != &vg->pvs))
-		log_print_unless_silent("Ignoring PVs on command line when reducing.");
-
-	/* Request confirmation before operations that are often mistakes. */
-	if ((lp->resizefs || (lp->resize == LV_REDUCE)) &&
-	    !_request_confirmation(lv, lp))
-		return_0;
-
-	if (lp->resizefs) {
-		if (!lp->nofsck &&
-		    !_fsadm_cmd(FSADM_CMD_CHECK, lv, 0, lp->force, &status)) {
-			if (status != FSADM_CHECK_FAILS_FOR_MOUNTED) {
-				log_error("Filesystem check failed.");
-				return 0;
-			}
-			/* some filesystems support online resize */
-		}
-
-		/* FIXME forks here */
-		if ((lp->resize == LV_REDUCE) &&
-		    !_fsadm_cmd(FSADM_CMD_RESIZE, lv, lp->extents, lp->force, NULL)) {
-			log_error("Filesystem resize failed.");
-			return 0;
-		}
-	}
-
-	if (!archive(vg))
-		return_0;
-
 	old_extents = lv->le_count;
 	log_verbose("%sing logical volume %s to %s%s",
 		    (lp->resize == LV_REDUCE) ? "Reduc" : "Extend",
@@ -5187,11 +5157,13 @@ static int _lvresize_volume(struct logical_volume *lv,
 		log_print_unless_silent("Size of logical volume %s unchanged from %s (%" PRIu32 " extents).",
 					display_lvname(lv),
 					display_size(cmd, (uint64_t) old_extents * vg->extent_size), old_extents);
-	else
+	else {
+		lp->size_changed = 1;
 		log_print_unless_silent("Size of logical volume %s changed from %s (%" PRIu32 " extents) to %s (%" PRIu32 " extents).",
 					display_lvname(lv),
 					display_size(cmd, (uint64_t) old_extents * vg->extent_size), old_extents,
 					display_size(cmd, (uint64_t) lv->le_count * vg->extent_size), lv->le_count);
+	}
 
 	return 1;
 }
@@ -5211,10 +5183,10 @@ static int _lvresize_prepare(struct logical_volume **lv,
 	else if (lp->extents && !_lvresize_extents_from_percent(*lv, lp, pvh))
 		return_0;
 
-	if (lp->extents && !_lvresize_adjust_extents(*lv, lp, pvh))
+	if (!_lvresize_adjust_extents(*lv, lp, pvh))
 		return_0;
 
-	if (lp->extents && !_lvresize_check_type(*lv, lp))
+	if (!_lvresize_check_type(*lv, lp))
 		return_0;
 
 	return 1;
@@ -5246,6 +5218,7 @@ int lv_resize(struct logical_volume *lv,
 	struct lvresize_params aux_lp;
 	int activated = 0;
 	int ret = 0;
+	int status;
 
 	if (!_lvresize_check(lv, lp))
 		return_0;
@@ -5271,8 +5244,8 @@ int lv_resize(struct logical_volume *lv,
 		}
 	} else if (lp->poolmetadata_size) {
 		if (!lp->extents && !lp->size) {
-			/* When only --poolmetadatasize give and not --size
-			 * swith directly to resize metadata LV */
+			/* When only --poolmetadatasize given and not --size
+			 * switch directly to resize metadata LV */
 			lv = first_seg(lv)->metadata_lv;
 			lp->size = lp->poolmetadata_size;
 			lp->sign = lp->poolmetadata_sign;
@@ -5287,9 +5260,44 @@ int lv_resize(struct logical_volume *lv,
 	if (aux_lv && !_lvresize_prepare(&aux_lv, &aux_lp, pvh))
 		return_0;
 
+	/* Always should have lp->size or lp->extents */
 	if (!_lvresize_prepare(&lv, lp, pvh))
 		return_0;
 
+	if (((lp->resize == LV_REDUCE) ||
+	     (aux_lv && aux_lp.resize == LV_REDUCE)) &&
+	    (pvh != &vg->pvs))
+		log_print_unless_silent("Ignoring PVs on command line when reducing.");
+
+	/* Request confirmation before operations that are often mistakes. */
+	/* aux_lv never resize fs */
+	if ((lp->resizefs || (lp->resize == LV_REDUCE)) &&
+	    !_request_confirmation(lv, lp))
+		return_0;
+
+	if (lp->resizefs) {
+		if (!lp->nofsck &&
+		    !_fsadm_cmd(FSADM_CMD_CHECK, lv, 0, lp->force, &status)) {
+			if (status != FSADM_CHECK_FAILS_FOR_MOUNTED) {
+				log_error("Filesystem check failed.");
+				return 0;
+			}
+			/* some filesystems support online resize */
+		}
+
+		/* FIXME forks here */
+		if ((lp->resize == LV_REDUCE) &&
+		    !_fsadm_cmd(FSADM_CMD_RESIZE, lv, lp->extents, lp->force, NULL)) {
+			log_error("Filesystem resize failed.");
+			return 0;
+		}
+	}
+
+	if (!lp->extents && (!aux_lv || !aux_lp.extents)) {
+		lp->extents = lv->le_count;
+		goto out; /* Nothing to do */
+	}
+
 	if (lv_is_thin_pool(lock_lv) &&  /* Lock holder is thin-pool */
 	    !lv_is_active(lock_lv)) {
 
@@ -5322,12 +5330,15 @@ int lv_resize(struct logical_volume *lv,
 	if (!lockd_lv(cmd, lock_lv, "ex", 0))
 		return_0;
 
+	if (!archive(vg))
+		return_0;
+
 	if (aux_lv) {
 		if (!_lvresize_volume(aux_lv, &aux_lp, pvh))
 			goto_bad;
 
 		/* store vg on disk(s) */
-		if (!lv_update_and_reload(lock_lv))
+		if (aux_lp.size_changed && !lv_update_and_reload(lock_lv))
 			goto_bad;
 	}
 
@@ -5335,6 +5346,9 @@ int lv_resize(struct logical_volume *lv,
 		goto_bad;
 
 	/* store vg on disk(s) */
+	if (!lp->size_changed)
+		goto out; /* No table reload needed */
+
 	if (!lv_update_and_reload(lock_lv))
 		goto_bad;
 
@@ -5349,7 +5363,7 @@ int lv_resize(struct logical_volume *lv,
 
 		backup(vg);
 	}
-
+out:
 	log_print_unless_silent("Logical volume %s successfully resized.",
 				display_lvname(lv));
 
diff --git a/lib/metadata/metadata-exported.h b/lib/metadata/metadata-exported.h
index 7765d23ae..84b510b59 100644
--- a/lib/metadata/metadata-exported.h
+++ b/lib/metadata/metadata-exported.h
@@ -637,6 +637,7 @@ struct lvresize_params {
 
 	int approx_alloc;
 	int extents_are_pes;	/* Is 'extents' counting PEs or LEs? */
+	int size_changed;	/* Was there actually a size change */
 };
 
 void pvcreate_params_set_defaults(struct pvcreate_params *pp);