From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52627) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XHfgJ-0006tv-OI for qemu-devel@nongnu.org; Wed, 13 Aug 2014 17:02:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XHfgD-0005Oi-IP for qemu-devel@nongnu.org; Wed, 13 Aug 2014 17:02:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:32366) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XHfgD-0005Oc-AK for qemu-devel@nongnu.org; Wed, 13 Aug 2014 17:01:57 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s7DL1uO7029850 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Wed, 13 Aug 2014 17:01:56 -0400 From: Max Reitz Date: Wed, 13 Aug 2014 23:01:43 +0200 Message-Id: <1407963710-4942-2-git-send-email-mreitz@redhat.com> In-Reply-To: <1407963710-4942-1-git-send-email-mreitz@redhat.com> References: <1407963710-4942-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH 1/8] qcow2: Factor out refcount accounting for check List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , Max Reitz Put the code for calculating the reference counts during qemu-img check into an own function. Signed-off-by: Max Reitz --- block/qcow2-refcount.c | 202 +++++++++++++++++++++++++++++-------------------- 1 file changed, 122 insertions(+), 80 deletions(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index d60e2fe..9793c27 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -1496,71 +1496,17 @@ done: } /* - * Checks an image for refcount consistency. - * - * Returns 0 if no errors are found, the number of errors in case the image is - * detected as corrupted, and -errno when an internal error occurred. + * Checks consistency of refblocks and accounts for each refblock in + * *refcount_table. */ -int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, - BdrvCheckMode fix) +static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res, + BdrvCheckMode fix, uint16_t **refcount_table, + int64_t *nb_clusters) { BDRVQcowState *s = bs->opaque; - int64_t size, i, highest_cluster, nb_clusters; - int refcount1, refcount2; - QCowSnapshot *sn; - uint16_t *refcount_table; - int ret; - - size = bdrv_getlength(bs->file); - if (size < 0) { - res->check_errors++; - return size; - } - - nb_clusters = size_to_clusters(s, size); - if (nb_clusters > INT_MAX) { - res->check_errors++; - return -EFBIG; - } - - refcount_table = g_try_malloc0(nb_clusters * sizeof(uint16_t)); - if (nb_clusters && refcount_table == NULL) { - res->check_errors++; - return -ENOMEM; - } - - res->bfi.total_clusters = - size_to_clusters(s, bs->total_sectors * BDRV_SECTOR_SIZE); - - /* header */ - inc_refcounts(bs, res, refcount_table, nb_clusters, - 0, s->cluster_size); - - /* current L1 table */ - ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters, - s->l1_table_offset, s->l1_size, CHECK_FRAG_INFO); - if (ret < 0) { - goto fail; - } + int64_t i; - /* snapshots */ - for(i = 0; i < s->nb_snapshots; i++) { - sn = s->snapshots + i; - ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters, - sn->l1_table_offset, sn->l1_size, 0); - if (ret < 0) { - goto fail; - } - } - inc_refcounts(bs, res, refcount_table, nb_clusters, - s->snapshots_offset, s->snapshots_size); - - /* refcount data */ - inc_refcounts(bs, res, refcount_table, nb_clusters, - s->refcount_table_offset, - s->refcount_table_size * sizeof(uint64_t)); - - for(i = 0; i < s->refcount_table_size; i++) { + for (i = 0; i < s->refcount_table_size; i++) { uint64_t offset, cluster; offset = s->refcount_table[i]; cluster = offset >> s->cluster_bits; @@ -1568,12 +1514,12 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, /* Refcount blocks are cluster aligned */ if (offset_into_cluster(s, offset)) { fprintf(stderr, "ERROR refcount block %" PRId64 " is not " - "cluster aligned; refcount table entry corrupted\n", i); + "cluster aligned; refcount table entry corrupted\n", i); res->corruptions++; continue; } - if (cluster >= nb_clusters) { + if (cluster >= *nb_clusters) { fprintf(stderr, "ERROR refcount block %" PRId64 " is outside image\n", i); res->corruptions++; @@ -1581,14 +1527,14 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, } if (offset != 0) { - inc_refcounts(bs, res, refcount_table, nb_clusters, - offset, s->cluster_size); - if (refcount_table[cluster] != 1) { + inc_refcounts(bs, res, *refcount_table, *nb_clusters, + offset, s->cluster_size); + if ((*refcount_table)[cluster] != 1) { fprintf(stderr, "%s refcount block %" PRId64 - " refcount=%d\n", - fix & BDRV_FIX_ERRORS ? "Repairing" : - "ERROR", - i, refcount_table[cluster]); + " refcount=%d\n", + fix & BDRV_FIX_ERRORS ? "Repairing" : + "ERROR", + i, (*refcount_table)[cluster]); if (fix & BDRV_FIX_ERRORS) { int64_t new_offset; @@ -1600,18 +1546,25 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, } /* update refcounts */ - if ((new_offset >> s->cluster_bits) >= nb_clusters) { + if ((new_offset >> s->cluster_bits) >= *nb_clusters) { /* increase refcount_table size if necessary */ - int old_nb_clusters = nb_clusters; - nb_clusters = (new_offset >> s->cluster_bits) + 1; - refcount_table = g_realloc(refcount_table, - nb_clusters * sizeof(uint16_t)); - memset(&refcount_table[old_nb_clusters], 0, (nb_clusters - - old_nb_clusters) * sizeof(uint16_t)); + int old_nb_clusters = *nb_clusters; + *nb_clusters = (new_offset >> s->cluster_bits) + 1; + + *refcount_table = g_try_realloc(*refcount_table, + *nb_clusters * sizeof(uint16_t)); + if (!*refcount_table) { + res->check_errors++; + return -ENOMEM; + } + + memset(&(*refcount_table)[old_nb_clusters], 0, + (*nb_clusters - old_nb_clusters) * + sizeof(uint16_t)); } - refcount_table[cluster]--; - inc_refcounts(bs, res, refcount_table, nb_clusters, - new_offset, s->cluster_size); + (*refcount_table)[cluster]--; + inc_refcounts(bs, res, *refcount_table, *nb_clusters, + new_offset, s->cluster_size); res->corruptions_fixed++; } else { @@ -1621,6 +1574,95 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, } } + return 0; +} + +/* + * Calculates an in-memory refcount table. + */ +static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res, + BdrvCheckMode fix, uint16_t **refcount_table, + int64_t *nb_clusters) +{ + BDRVQcowState *s = bs->opaque; + QCowSnapshot *sn; + int64_t i; + int ret; + + if (!*refcount_table) { + *refcount_table = g_try_malloc0(*nb_clusters * sizeof(uint16_t)); + if (*nb_clusters && !*refcount_table) { + res->check_errors++; + return -ENOMEM; + } + } + + /* header */ + inc_refcounts(bs, res, *refcount_table, *nb_clusters, + 0, s->cluster_size); + + /* current L1 table */ + ret = check_refcounts_l1(bs, res, *refcount_table, *nb_clusters, + s->l1_table_offset, s->l1_size, CHECK_FRAG_INFO); + if (ret < 0) { + return ret; + } + + /* snapshots */ + for (i = 0; i < s->nb_snapshots; i++) { + sn = s->snapshots + i; + ret = check_refcounts_l1(bs, res, *refcount_table, *nb_clusters, + sn->l1_table_offset, sn->l1_size, 0); + if (ret < 0) { + return ret; + } + } + inc_refcounts(bs, res, *refcount_table, *nb_clusters, + s->snapshots_offset, s->snapshots_size); + + /* refcount data */ + inc_refcounts(bs, res, *refcount_table, *nb_clusters, + s->refcount_table_offset, + s->refcount_table_size * sizeof(uint64_t)); + + return check_refblocks(bs, res, fix, refcount_table, nb_clusters); +} + +/* + * Checks an image for refcount consistency. + * + * Returns 0 if no errors are found, the number of errors in case the image is + * detected as corrupted, and -errno when an internal error occurred. + */ +int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, + BdrvCheckMode fix) +{ + BDRVQcowState *s = bs->opaque; + int64_t size, i, highest_cluster, nb_clusters; + int refcount1, refcount2; + uint16_t *refcount_table = NULL; + int ret; + + size = bdrv_getlength(bs->file); + if (size < 0) { + res->check_errors++; + return size; + } + + nb_clusters = size_to_clusters(s, size); + if (nb_clusters > INT_MAX) { + res->check_errors++; + return -EFBIG; + } + + res->bfi.total_clusters = + size_to_clusters(s, bs->total_sectors * BDRV_SECTOR_SIZE); + + ret = calculate_refcounts(bs, res, fix, &refcount_table, &nb_clusters); + if (ret < 0) { + goto fail; + } + /* compare ref counts */ for (i = 0, highest_cluster = 0; i < nb_clusters; i++) { refcount1 = get_refcount(bs, i); -- 2.0.3