Adjust region and stripe sizes on small VG extents

lib/metadata/lv_manip.c

@@ -1229,6 +1229,8 @@ static uint32_t _calc_area_multiple(const struct segment_type *segtype,
 	}
 
 	/*
+	 * FIXME:
+	 *
 	 * RAID10 - only has 2-way mirror right now.
 	 *          If we are to move beyond 2-way RAID10, then
 	 *          the 'stripes' argument will always need to
@@ -1256,14 +1258,14 @@ static int _lv_segment_reduce(struct lv_segment *seg, uint32_t reduction)
 	uint32_t area_reduction, s;
 
 	/* Caller must ensure exact divisibility */
-	if (seg_is_striped(seg)) {
+	if (seg_is_striped(seg) || (seg_is_raid(seg) && !seg_is_raid1(seg))) {
 		if (reduction % seg->area_count) {
 			log_error("Segment extent reduction %" PRIu32
 				  " not divisible by #stripes %" PRIu32,
 				  reduction, seg->area_count);
 			return 0;
 		}
-		area_reduction = (reduction / seg->area_count);
+		area_reduction = (reduction / (seg->area_count - seg->segtype->parity_devs));
 	} else
 		area_reduction = reduction;
 
@@ -3875,8 +3877,8 @@ static int _lv_extend_layered_lv(struct alloc_handle *ah,
 	if (seg_is_raid(seg)) {
 		stripes = 1;
 		stripe_size = 0;
-		if (seg_is_any_raid0(seg))
+		area_multiple = _calc_area_multiple(seg->segtype, seg->area_count, seg_is_raid1(seg) ? 1 : seg->area_count - seg->segtype->parity_devs);
-			area_multiple = seg->area_count;
+printf("area_multiple=%u\n", area_multiple);
 	}
 
 	for (fa = first_area, s = 0; s < seg->area_count; s++) {
@@ -4000,7 +4002,7 @@ static int _lv_extend_layered_lv(struct alloc_handle *ah,
 }
 
 /* Adjust region and stripe size on very small LVs */
-static void _lv_adjust_region_and_stripe_size(struct logical_volume *lv)
+void lv_adjust_region_and_stripe_size(struct logical_volume *lv)
 {
 	uint32_t size;
 	struct lv_segment *seg = first_seg(lv);
@@ -4135,7 +4137,7 @@ int lv_extend(struct logical_volume *lv,
 					 stripe_size, 0u, 0)))
 			stack;
 		if (empty)
-			_lv_adjust_region_and_stripe_size(lv);
+			lv_adjust_region_and_stripe_size(lv);
 	} else {
 		/*
 		 * For RAID, all the devices are AREA_LV.
@@ -4162,7 +4164,7 @@ int lv_extend(struct logical_volume *lv,
 			goto_out;
 
 		if (empty)
-			_lv_adjust_region_and_stripe_size(lv);
+			lv_adjust_region_and_stripe_size(lv);
 
 		if (!(r = _raid_rmeta_size_sufficient(lv))) {
 			if (!old_extents &&

lib/metadata/merge.c

@@ -415,7 +415,6 @@ int check_lv_segments(struct logical_volume *lv, int complete_vg)
 
 		area_multiplier = segtype_is_striped(seg->segtype) ?
 					seg->area_count : 1;
-
 		if (seg->area_len * area_multiplier != seg->len) {
 			log_error("LV %s: segment %u has inconsistent "
 				  "area_len %u",

lib/metadata/metadata-exported.h

@@ -30,10 +30,11 @@
 #define MAX_STRIPES 128U
 #define SECTOR_SHIFT 9L
 #define SECTOR_SIZE ( 1L << SECTOR_SHIFT )
-#define STRIPE_SIZE_MIN 2 /* 2 sectors minimum */
+#define STRIPE_SIZE_MIN 8 /* 8 sectors minimum to allow for raid takover of striped */
 #define STRIPE_SIZE_MAX ( 512L * 1024L >> SECTOR_SHIFT)	/* 512 KB in sectors */
 #define STRIPE_SIZE_LIMIT ((UINT_MAX >> 2) + 1)
 #define MAX_RESTRICTED_LVS 255	/* Used by FMT_RESTRICTED_LVIDS */
+#define MIN_EXTENT_SIZE 8 /* 8 sectors minimum to allow for raid takover of striped */
 #define MAX_EXTENT_SIZE ((uint32_t) -1)
 #define MIN_NON_POWER2_EXTENT_SIZE (128U * 2U)	/* 128KB in sectors */
 
@@ -825,6 +826,7 @@ int lv_rename_update(struct cmd_context *cmd, struct logical_volume *lv,
 /* Updates and reloads metadata for given lv */
 int lv_update_and_reload(struct logical_volume *lv);
 int lv_update_and_reload_origin(struct logical_volume *lv);
+void lv_adjust_region_and_stripe_size(struct  logical_volume *lv);
 
 uint32_t extents_from_size(struct cmd_context *cmd, uint64_t size,
 			   uint32_t extent_size);

lib/metadata/metadata.c

@@ -1008,6 +1008,11 @@ int vgcreate_params_validate(struct cmd_context *cmd,
 		return 0;
 	}
 
+	if (vp->extent_size < MIN_EXTENT_SIZE) {
+		log_error("Physical extent size < 4 KiB restricts RAID use.");
+		return 0;
+	}
+
 	if (!(cmd->fmt->features & FMT_UNLIMITED_VOLS)) {
 		if (!vp->max_lv)
 			vp->max_lv = 255;

lib/metadata/raid_manip.c

@@ -651,6 +651,7 @@ static int _alloc_image_components(struct logical_volume *lv,
 	if (!region_size)
 		region_size = get_default_region_size(lv->vg->cmd);
 
+	if (seg_is_raid(seg))
 	if (seg_is_raid(seg))
 		segtype = seg->segtype;
 	else if (!(segtype = get_segtype_from_string(lv->vg->cmd, SEG_TYPE_NAME_RAID1)))
@@ -2985,6 +2986,11 @@ static int _striped_or_raid0_to_raid45610_wrapper(TAKEOVER_FN_ARGS)
 			return 0;
 	}
 
+	/* FIXME Hard-coded raid0/4/5/6 */
+	/* Be prepared for any image addition -> raid5/6 */
+	if (seg_is_any_raid0(seg))
+		seg->area_len = seg->extents_copied = seg->len / seg->area_count;
+
 	/* Add the additional component LV pairs */
 	log_debug_metadata("Adding %" PRIu32 " component LV pair(s) to %s", new_image_count - lv_raid_image_count(lv),
 			   display_lvname(lv));
@@ -2999,10 +3005,9 @@ static int _striped_or_raid0_to_raid45610_wrapper(TAKEOVER_FN_ARGS)
 
 	seg->segtype = new_segtype;
 	seg->region_size = new_region_size;
-	/* FIXME Hard-coded raid0 to raid4 */
-	seg->area_len = seg->len;
 
 	_check_and_adjust_region_size(lv);
+	lv_adjust_region_and_stripe_size(lv);
 
 	log_debug_metadata("Updating VG metadata and reloading %s LV %s",
 			   lvseg_name(seg), display_lvname(lv));
@@ -3411,12 +3416,6 @@ static int _set_convenient_raid456_segtype_to(const struct lv_segment *seg_from,
 		    !segtype_is_raid5_n(*segtype)) {
 			log_error("Conversion to raid5_n not yet supported.");
 			return 0;
-
-		/* If this is any raid6 conversion request -> enforce raid6_n_6, because we convert from striped */
-		} else if (segtype_is_any_raid6(*segtype) &&
-			   !segtype_is_raid6_n_6(*segtype)) {
-			log_error("Conversion to raid6_n_6 not yet supported.");
-			return 0;
 		}
 
 	/* Got to do check for raid5 -> raid6 ... */