xfs: split and refactor zone validation

Currently xfs_zone_validate mixes validating the software zone state in
the XFS realtime group with validating the hardware state reported in
struct blk_zone and deriving the write pointer from that.

Move all code that works on the realtime group to xfs_init_zone, and only
keep the hardware state validation in xfs_zone_validate.  This makes the
code more clear, and allows for better reuse in userspace.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>

Author: Christoph Hellwig

fs/xfs/libxfs/xfs_zones.c

@@ -15,173 +15,102 @@
 #include "xfs_zones.h"
 
 static bool
-xfs_zone_validate_empty(
+xfs_validate_blk_zone_seq(
+	struct xfs_mount	*mp,
 	struct blk_zone		*zone,
-	struct xfs_rtgroup	*rtg,
+	unsigned int		zone_no,
 	xfs_rgblock_t		*write_pointer)
 {
-	struct xfs_mount	*mp = rtg_mount(rtg);
-
-	if (rtg_rmap(rtg)->i_used_blocks > 0) {
-		xfs_warn(mp, "empty zone %u has non-zero used counter (0x%x).",
-			 rtg_rgno(rtg), rtg_rmap(rtg)->i_used_blocks);
-		return false;
-	}
-
-	*write_pointer = 0;
-	return true;
-}
-
-static bool
-xfs_zone_validate_wp(
-	struct blk_zone		*zone,
-	struct xfs_rtgroup	*rtg,
-	xfs_rgblock_t		*write_pointer)
-{
-	struct xfs_mount	*mp = rtg_mount(rtg);
-	xfs_rtblock_t		wp_fsb = xfs_daddr_to_rtb(mp, zone->wp);
-
-	if (rtg_rmap(rtg)->i_used_blocks > rtg->rtg_extents) {
-		xfs_warn(mp, "zone %u has too large used counter (0x%x).",
-			 rtg_rgno(rtg), rtg_rmap(rtg)->i_used_blocks);
-		return false;
-	}
-
-	if (xfs_rtb_to_rgno(mp, wp_fsb) != rtg_rgno(rtg)) {
-		xfs_warn(mp, "zone %u write pointer (0x%llx) outside of zone.",
-			 rtg_rgno(rtg), wp_fsb);
-		return false;
-	}
-
-	*write_pointer = xfs_rtb_to_rgbno(mp, wp_fsb);
-	if (*write_pointer >= rtg->rtg_extents) {
-		xfs_warn(mp, "zone %u has invalid write pointer (0x%x).",
-			 rtg_rgno(rtg), *write_pointer);
-		return false;
-	}
-
-	return true;
-}
-
-static bool
-xfs_zone_validate_full(
-	struct blk_zone		*zone,
-	struct xfs_rtgroup	*rtg,
-	xfs_rgblock_t		*write_pointer)
-{
-	struct xfs_mount	*mp = rtg_mount(rtg);
-
-	if (rtg_rmap(rtg)->i_used_blocks > rtg->rtg_extents) {
-		xfs_warn(mp, "zone %u has too large used counter (0x%x).",
-			 rtg_rgno(rtg), rtg_rmap(rtg)->i_used_blocks);
-		return false;
-	}
-
-	*write_pointer = rtg->rtg_extents;
-	return true;
-}
-
-static bool
-xfs_zone_validate_seq(
-	struct blk_zone		*zone,
-	struct xfs_rtgroup	*rtg,
-	xfs_rgblock_t		*write_pointer)
-{
-	struct xfs_mount	*mp = rtg_mount(rtg);
-
 	switch (zone->cond) {
 	case BLK_ZONE_COND_EMPTY:
-		return xfs_zone_validate_empty(zone, rtg, write_pointer);
+		*write_pointer = 0;
+		return true;
 	case BLK_ZONE_COND_IMP_OPEN:
 	case BLK_ZONE_COND_EXP_OPEN:
 	case BLK_ZONE_COND_CLOSED:
 	case BLK_ZONE_COND_ACTIVE:
-		return xfs_zone_validate_wp(zone, rtg, write_pointer);
+		if (zone->wp < zone->start ||
+		    zone->wp >= zone->start + zone->capacity) {
+			xfs_warn(mp,
+	"zone %u write pointer (%llu) outside of zone.",
+				zone_no, zone->wp);
+			return false;
+		}
+
+		*write_pointer = XFS_BB_TO_FSB(mp, zone->wp - zone->start);
+		return true;
 	case BLK_ZONE_COND_FULL:
-		return xfs_zone_validate_full(zone, rtg, write_pointer);
+		*write_pointer = XFS_BB_TO_FSB(mp, zone->capacity);
+		return true;
 	case BLK_ZONE_COND_NOT_WP:
 	case BLK_ZONE_COND_OFFLINE:
 	case BLK_ZONE_COND_READONLY:
 		xfs_warn(mp, "zone %u has unsupported zone condition 0x%x.",
-			rtg_rgno(rtg), zone->cond);
+			zone_no, zone->cond);
 		return false;
 	default:
 		xfs_warn(mp, "zone %u has unknown zone condition 0x%x.",
-			rtg_rgno(rtg), zone->cond);
+			zone_no, zone->cond);
 		return false;
 	}
 }
 
 static bool
-xfs_zone_validate_conv(
+xfs_validate_blk_zone_conv(
+	struct xfs_mount	*mp,
 	struct blk_zone		*zone,
-	struct xfs_rtgroup	*rtg)
+	unsigned int		zone_no)
 {
-	struct xfs_mount	*mp = rtg_mount(rtg);
-
 	switch (zone->cond) {
 	case BLK_ZONE_COND_NOT_WP:
 		return true;
 	default:
 		xfs_warn(mp,
 "conventional zone %u has unsupported zone condition 0x%x.",
-			 rtg_rgno(rtg), zone->cond);
+			 zone_no, zone->cond);
 		return false;
 	}
 }
 
 bool
-xfs_zone_validate(
+xfs_validate_blk_zone(
+	struct xfs_mount	*mp,
 	struct blk_zone		*zone,
-	struct xfs_rtgroup	*rtg,
+	unsigned int		zone_no,
+	uint32_t		expected_size,
+	uint32_t		expected_capacity,
 	xfs_rgblock_t		*write_pointer)
 {
-	struct xfs_mount	*mp = rtg_mount(rtg);
-	struct xfs_groups	*g = &mp->m_groups[XG_TYPE_RTG];
-	uint32_t		expected_size;
-
 	/*
 	 * Check that the zone capacity matches the rtgroup size stored in the
 	 * superblock.  Note that all zones including the last one must have a
 	 * uniform capacity.
 	 */
-	if (XFS_BB_TO_FSB(mp, zone->capacity) != g->blocks) {
+	if (XFS_BB_TO_FSB(mp, zone->capacity) != expected_capacity) {
 		xfs_warn(mp,
-"zone %u capacity (0x%llx) does not match RT group size (0x%x).",
-			rtg_rgno(rtg), XFS_BB_TO_FSB(mp, zone->capacity),
-			g->blocks);
+"zone %u capacity (%llu) does not match RT group size (%u).",
+			zone_no, XFS_BB_TO_FSB(mp, zone->capacity),
+			expected_capacity);
 		return false;
 	}
 
-	if (g->has_daddr_gaps) {
-		expected_size = 1 << g->blklog;
-	} else {
-		if (zone->len != zone->capacity) {
-			xfs_warn(mp,
-"zone %u has capacity != size ((0x%llx vs 0x%llx)",
-				rtg_rgno(rtg),
-				XFS_BB_TO_FSB(mp, zone->len),
-				XFS_BB_TO_FSB(mp, zone->capacity));
-			return false;
-		}
-		expected_size = g->blocks;
-	}
-
 	if (XFS_BB_TO_FSB(mp, zone->len) != expected_size) {
 		xfs_warn(mp,
-"zone %u length (0x%llx) does match geometry (0x%x).",
-			rtg_rgno(rtg), XFS_BB_TO_FSB(mp, zone->len),
+"zone %u length (%llu) does not match geometry (%u).",
+			zone_no, XFS_BB_TO_FSB(mp, zone->len),
 			expected_size);
+		return false;
 	}
 
 	switch (zone->type) {
 	case BLK_ZONE_TYPE_CONVENTIONAL:
-		return xfs_zone_validate_conv(zone, rtg);
+		return xfs_validate_blk_zone_conv(mp, zone, zone_no);
 	case BLK_ZONE_TYPE_SEQWRITE_REQ:
-		return xfs_zone_validate_seq(zone, rtg, write_pointer);
+		return xfs_validate_blk_zone_seq(mp, zone, zone_no,
+				write_pointer);
 	default:
 		xfs_warn(mp, "zoned %u has unsupported type 0x%x.",
-			rtg_rgno(rtg), zone->type);
+			zone_no, zone->type);
 		return false;
 	}
 }

fs/xfs/libxfs/xfs_zones.h

@@ -37,7 +37,8 @@ struct blk_zone;
  */
 #define XFS_DEFAULT_MAX_OPEN_ZONES	128
 
-bool xfs_zone_validate(struct blk_zone *zone, struct xfs_rtgroup *rtg,
-	xfs_rgblock_t *write_pointer);
+bool xfs_validate_blk_zone(struct xfs_mount *mp, struct blk_zone *zone,
+	unsigned int zone_no, uint32_t expected_size,
+	uint32_t expected_capacity, xfs_rgblock_t *write_pointer);
 
 #endif /* _LIBXFS_ZONES_H */

fs/xfs/xfs_zone_alloc.c

@@ -977,13 +977,15 @@ xfs_free_open_zones(
 
 struct xfs_init_zones {
 	struct xfs_mount	*mp;
+	uint32_t		zone_size;
+	uint32_t		zone_capacity;
 	uint64_t		available;
 	uint64_t		reclaimable;
 };
 
 /*
  * For sequential write required zones, we restart writing at the hardware write
- * pointer returned by xfs_zone_validate().
+ * pointer returned by xfs_validate_blk_zone().
  *
  * For conventional zones or conventional devices we have to query the rmap to
  * find the highest recorded block and set the write pointer to the block after
@@ -1018,6 +1020,25 @@ xfs_init_zone(
 	uint32_t		used = rtg_rmap(rtg)->i_used_blocks;
 	int			error;
 
+	if (write_pointer > rtg->rtg_extents) {
+		xfs_warn(mp, "zone %u has invalid write pointer (0x%x).",
+			 rtg_rgno(rtg), write_pointer);
+		return -EFSCORRUPTED;
+	}
+
+	if (used > rtg->rtg_extents) {
+		xfs_warn(mp,
+"zone %u has used counter (0x%x) larger than zone capacity (0x%llx).",
+			 rtg_rgno(rtg), used, rtg->rtg_extents);
+		return -EFSCORRUPTED;
+	}
+
+	if (write_pointer == 0 && used != 0) {
+		xfs_warn(mp, "empty zone %u has non-zero used counter (0x%x).",
+			rtg_rgno(rtg), used);
+		return -EFSCORRUPTED;
+	}
+
 	/*
 	 * If there are no used blocks, but the zone is not in empty state yet
 	 * we lost power before the zoned reset.  In that case finish the work
@@ -1081,7 +1102,8 @@ xfs_get_zone_info_cb(
 		xfs_warn(mp, "realtime group not found for zone %u.", rgno);
 		return -EFSCORRUPTED;
 	}
-	if (!xfs_zone_validate(zone, rtg, &write_pointer)) {
+	if (!xfs_validate_blk_zone(mp, zone, idx, iz->zone_size,
+			iz->zone_capacity, &write_pointer)) {
 		xfs_rtgroup_rele(rtg);
 		return -EFSCORRUPTED;
 	}
@@ -1227,6 +1249,8 @@ xfs_mount_zones(
 {
 	struct xfs_init_zones	iz = {
 		.mp		= mp,
+		.zone_capacity	= mp->m_groups[XG_TYPE_RTG].blocks,
+		.zone_size	= xfs_rtgroup_raw_size(mp),
 	};
 	struct xfs_buftarg	*bt = mp->m_rtdev_targp;
 	xfs_extlen_t		zone_blocks = mp->m_groups[XG_TYPE_RTG].blocks;