- Correctly read gang header from raidz.

- Decompress assembled gang block data if compressed.
- Verify checksum of a gang header.
- Verify checksum of assembled gang block data.
- Verify checksum of uber block.

Submitted by:	avg
MFC after:	3 days

1 files changed, 51 insertions, 51 deletions

diff --git a/sys/boot/zfs/zfsimpl.c b/sys/boot/zfs/zfsimpl.c
index dd721ed..c97c2de 100644
--- a/sys/boot/zfs/zfsimpl.c
+++ b/sys/boot/zfs/zfsimpl.c
@@ -347,7 +347,7 @@ vdev_read_phys(vdev_t *vdev, const blkptr_t *bp, void *buf,
 	rc = vdev->v_phys_read(vdev, vdev->v_read_priv, offset, buf, psize);
 	if (rc)
 		return (rc);
-	if (bp && zio_checksum_verify(bp, buf, offset, psize))
+	if (bp && zio_checksum_verify(bp, buf))
 		return (EIO);
 
 	return (0);
@@ -798,6 +798,7 @@ vdev_probe(vdev_phys_read_t *read, void *read_priv, spa_t **spap)
 	BP_SET_PSIZE(&bp, sizeof(vdev_phys_t));
 	BP_SET_CHECKSUM(&bp, ZIO_CHECKSUM_LABEL);
 	BP_SET_COMPRESS(&bp, ZIO_COMPRESS_OFF);
+	DVA_SET_OFFSET(BP_IDENTITY(&bp), off);
 	ZIO_SET_CHECKSUM(&bp.blk_cksum, off, 0, 0, 0);
 	if (vdev_read_phys(&vtmp, &bp, vdev_label, off, 0))
 		return (EIO);
@@ -940,7 +941,7 @@ vdev_probe(vdev_phys_read_t *read, void *read_priv, spa_t **spap)
 		BP_SET_COMPRESS(&bp, ZIO_COMPRESS_OFF);
 		ZIO_SET_CHECKSUM(&bp.blk_cksum, off, 0, 0, 0);
 
-		if (vdev_read_phys(vdev, NULL, upbuf, off, VDEV_UBERBLOCK_SIZE(vdev)))
+		if (vdev_read_phys(vdev, &bp, upbuf, off, 0))
 			continue;
 
 		if (up->ub_magic != UBERBLOCK_MAGIC)
@@ -973,35 +974,39 @@ ilog2(int n)
 }
 
 static int
-zio_read_gang(spa_t *spa, const blkptr_t *bp, const dva_t *dva, void *buf)
+zio_read_gang(spa_t *spa, const blkptr_t *bp, void *buf)
 {
+	blkptr_t gbh_bp;
 	zio_gbh_phys_t zio_gb;
-	vdev_t *vdev;
-	int vdevid;
-	off_t offset;
+	char *pbuf;
 	int i;
 
-	vdevid = DVA_GET_VDEV(dva);
-	offset = DVA_GET_OFFSET(dva);
-	STAILQ_FOREACH(vdev, &spa->spa_vdevs, v_childlink)
-		if (vdev->v_id == vdevid)
-			break;
-	if (!vdev || !vdev->v_read)
-		return (EIO);
-
-	if (vdev->v_read(vdev, bp, &zio_gb, offset, SPA_GANGBLOCKSIZE))
+	/* Artificial BP for gang block header. */
+	gbh_bp = *bp;
+	BP_SET_PSIZE(&gbh_bp, SPA_GANGBLOCKSIZE);
+	BP_SET_LSIZE(&gbh_bp, SPA_GANGBLOCKSIZE);
+	BP_SET_CHECKSUM(&gbh_bp, ZIO_CHECKSUM_GANG_HEADER);
+	BP_SET_COMPRESS(&gbh_bp, ZIO_COMPRESS_OFF);
+	for (i = 0; i < SPA_DVAS_PER_BP; i++)
+		DVA_SET_GANG(&gbh_bp.blk_dva[i], 0);
+
+	/* Read gang header block using the artificial BP. */
+	if (zio_read(spa, &gbh_bp, &zio_gb))
 		return (EIO);
 
+	pbuf = buf;
 	for (i = 0; i < SPA_GBH_NBLKPTRS; i++) {
 		blkptr_t *gbp = &zio_gb.zg_blkptr[i];
 
 		if (BP_IS_HOLE(gbp))
 			continue;
-		if (zio_read(spa, gbp, buf))
+		if (zio_read(spa, gbp, pbuf))
 			return (EIO);
-		buf = (char*)buf + BP_GET_PSIZE(gbp);
+		pbuf += BP_GET_PSIZE(gbp);
 	}
- 
+
+	if (zio_checksum_verify(bp, buf))
+		return (EIO);
 	return (0);
 }
 
@@ -1024,46 +1029,41 @@ zio_read(spa_t *spa, const blkptr_t *bp, void *buf)
 		if (!dva->dva_word[0] && !dva->dva_word[1])
 			continue;
 
-		if (DVA_GET_GANG(dva)) {
-			error = zio_read_gang(spa, bp, dva, buf);
-			if (error != 0)
-				continue;
-		} else {
-			vdevid = DVA_GET_VDEV(dva);
-			offset = DVA_GET_OFFSET(dva);
-			STAILQ_FOREACH(vdev, &spa->spa_vdevs, v_childlink) {
-				if (vdev->v_id == vdevid)
-					break;
-			}
-			if (!vdev || !vdev->v_read)
-				continue;
+		vdevid = DVA_GET_VDEV(dva);
+		offset = DVA_GET_OFFSET(dva);
+		STAILQ_FOREACH(vdev, &spa->spa_vdevs, v_childlink) {
+			if (vdev->v_id == vdevid)
+				break;
+		}
+		if (!vdev || !vdev->v_read)
+			continue;
 
-			size = BP_GET_PSIZE(bp);
+		size = BP_GET_PSIZE(bp);
+		if (vdev->v_read == vdev_raidz_read) {
 			align = 1ULL << vdev->v_top->v_ashift;
 			if (P2PHASE(size, align) != 0)
 				size = P2ROUNDUP(size, align);
-			if (size != BP_GET_PSIZE(bp) || cpfunc != ZIO_COMPRESS_OFF)
-				pbuf = zfs_alloc(size);
-			else
-				pbuf = buf;
+		}
+		if (size != BP_GET_PSIZE(bp) || cpfunc != ZIO_COMPRESS_OFF)
+			pbuf = zfs_alloc(size);
+		else
+			pbuf = buf;
 
+		if (DVA_GET_GANG(dva))
+			error = zio_read_gang(spa, bp, pbuf);
+		else
 			error = vdev->v_read(vdev, bp, pbuf, offset, size);
-			if (error == 0) {
-				if (cpfunc != ZIO_COMPRESS_OFF) {
-					error = zio_decompress_data(cpfunc,
-					    pbuf, BP_GET_PSIZE(bp), buf,
-					    BP_GET_LSIZE(bp));
-				} else if (size != BP_GET_PSIZE(bp)) {
-					bcopy(pbuf, buf, BP_GET_PSIZE(bp));
-				}
-			}
-			if (buf != pbuf)
-				zfs_free(pbuf, size);
-			if (error != 0)
-				continue;
+		if (error == 0) {
+			if (cpfunc != ZIO_COMPRESS_OFF)
+				error = zio_decompress_data(cpfunc, pbuf,
+				    BP_GET_PSIZE(bp), buf, BP_GET_LSIZE(bp));
+			else if (size != BP_GET_PSIZE(bp))
+				bcopy(pbuf, buf, BP_GET_PSIZE(bp));
 		}
-		error = 0;
-		break;
+		if (buf != pbuf)
+			zfs_free(pbuf, size);
+		if (error == 0)
+			break;
 	}
 	if (error != 0)
 		printf("ZFS: i/o error - all block copies unavailable\n");