From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38545) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XKXOK-00043h-Km for qemu-devel@nongnu.org; Thu, 21 Aug 2014 14:47:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XKXOB-0006SB-Ix for qemu-devel@nongnu.org; Thu, 21 Aug 2014 14:47:20 -0400 Received: from dew.nodalink.com ([95.130.14.197]:39689) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XKXOB-0006Ra-9L for qemu-devel@nongnu.org; Thu, 21 Aug 2014 14:47:11 -0400 Date: Thu, 21 Aug 2014 18:47:07 +0000 From: =?iso-8859-1?Q?Beno=EEt?= Canet Message-ID: <20140821184707.GA15636@nodalink.com> References: <1408115786-13640-1-git-send-email-mreitz@redhat.com> <1408115786-13640-3-git-send-email-mreitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1408115786-13640-3-git-send-email-mreitz@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v2 2/9] qcow2: Factor out refcount accounting for check List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz Cc: Kevin Wolf , qemu-devel@nongnu.org, Stefan Hajnoczi , =?iso-8859-1?Q?Beno=EEt?= Canet On Fri, Aug 15, 2014 at 05:16:19PM +0200, Max Reitz wrote: > Put the code for calculating the reference counts during qemu-img check > into an own function. >=20 > Also, do not use g_realloc() for increasing the size of the in-memory > refcount table, but rather g_try_realloc(). >=20 > Signed-off-by: Max Reitz > --- > block/qcow2-refcount.c | 188 ++++++++++++++++++++++++++++++-----------= -------- > 1 file changed, 115 insertions(+), 73 deletions(-) >=20 > diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c > index d60e2fe..b3c4edd 100644 > --- a/block/qcow2-refcount.c > +++ b/block/qcow2-refcount.c > @@ -1496,69 +1496,15 @@ done: > } > =20 > /* > - * 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_tabl= e, > + int64_t *nb_clusters) > { > BDRVQcowState *s =3D bs->opaque; > - int64_t size, i, highest_cluster, nb_clusters; > - int refcount1, refcount2; > - QCowSnapshot *sn; > - uint16_t *refcount_table; > - int ret; > - > - size =3D bdrv_getlength(bs->file); > - if (size < 0) { > - res->check_errors++; > - return size; > - } > - > - nb_clusters =3D size_to_clusters(s, size); > - if (nb_clusters > INT_MAX) { > - res->check_errors++; > - return -EFBIG; > - } > - > - refcount_table =3D g_try_malloc0(nb_clusters * sizeof(uint16_t)); > - if (nb_clusters && refcount_table =3D=3D NULL) { > - res->check_errors++; > - return -ENOMEM; > - } > - > - res->bfi.total_clusters =3D > - 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 =3D check_refcounts_l1(bs, res, refcount_table, nb_clusters, > - s->l1_table_offset, s->l1_size, CHECK_FRA= G_INFO); > - if (ret < 0) { > - goto fail; > - } > - > - /* snapshots */ > - for(i =3D 0; i < s->nb_snapshots; i++) { > - sn =3D s->snapshots + i; > - ret =3D check_refcounts_l1(bs, res, refcount_table, nb_cluster= s, > - 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)); > + int64_t i; > =20 > for(i =3D 0; i < s->refcount_table_size; i++) { > uint64_t offset, cluster; > @@ -1573,7 +1519,7 @@ int qcow2_check_refcounts(BlockDriverState *bs, B= drvCheckResult *res, > continue; > } > =20 > - if (cluster >=3D nb_clusters) { > + if (cluster >=3D *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, > } > =20 > if (offset !=3D 0) { > - inc_refcounts(bs, res, refcount_table, nb_clusters, > + inc_refcounts(bs, res, *refcount_table, *nb_clusters, > offset, s->cluster_size); > - if (refcount_table[cluster] !=3D 1) { > + if ((*refcount_table)[cluster] !=3D 1) { > fprintf(stderr, "%s refcount block %" PRId64 > " refcount=3D%d\n", > fix & BDRV_FIX_ERRORS ? "Repairing" : > "ERROR", > - i, refcount_table[cluster]); > + i, (*refcount_table)[cluster]); > =20 > if (fix & BDRV_FIX_ERRORS) { > int64_t new_offset; > @@ -1600,17 +1546,24 @@ int qcow2_check_refcounts(BlockDriverState *bs,= BdrvCheckResult *res, > } > =20 > /* update refcounts */ > - if ((new_offset >> s->cluster_bits) >=3D nb_cluste= rs) { > + if ((new_offset >> s->cluster_bits) >=3D *nb_clust= ers) { > /* increase refcount_table size if necessary *= / > - int old_nb_clusters =3D nb_clusters; > - nb_clusters =3D (new_offset >> s->cluster_bits= ) + 1; > - refcount_table =3D g_realloc(refcount_table, > - nb_clusters * sizeof(uint16_t)); > - memset(&refcount_table[old_nb_clusters], 0, (n= b_clusters > - - old_nb_clusters) * sizeof(uint16_t))= ; > + int old_nb_clusters =3D *nb_clusters; > + *nb_clusters =3D (new_offset >> s->cluster_bit= s) + 1; > + > + *refcount_table =3D g_try_realloc(*refcount_ta= ble, > + *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= , > + (*refcount_table)[cluster]--; > + inc_refcounts(bs, res, *refcount_table, *nb_cluste= rs, > new_offset, s->cluster_size); > =20 > res->corruptions_fixed++; > @@ -1621,6 +1574,95 @@ int qcow2_check_refcounts(BlockDriverState *bs, = BdrvCheckResult *res, > } > } > =20 > + 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 =3D bs->opaque; > + QCowSnapshot *sn; > + int64_t i; > + int ret; > + > + if (!*refcount_table) { > + *refcount_table =3D 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 =3D check_refcounts_l1(bs, res, *refcount_table, *nb_clusters, > + s->l1_table_offset, s->l1_size, CHECK_FRA= G_INFO); > + if (ret < 0) { > + return ret; > + } > + > + /* snapshots */ > + for (i =3D 0; i < s->nb_snapshots; i++) { > + sn =3D s->snapshots + i; > + ret =3D check_refcounts_l1(bs, res, *refcount_table, *nb_clust= ers, > + 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 =3D bs->opaque; > + int64_t size, i, highest_cluster, nb_clusters; > + int refcount1, refcount2; > + uint16_t *refcount_table =3D NULL; > + int ret; > + > + size =3D bdrv_getlength(bs->file); > + if (size < 0) { > + res->check_errors++; > + return size; > + } > + > + nb_clusters =3D size_to_clusters(s, size); > + if (nb_clusters > INT_MAX) { > + res->check_errors++; > + return -EFBIG; > + } > + > + res->bfi.total_clusters =3D > + size_to_clusters(s, bs->total_sectors * BDRV_SECTOR_SIZE); > + > + ret =3D calculate_refcounts(bs, res, fix, &refcount_table, &nb_clu= sters); > + if (ret < 0) { > + goto fail; > + } > + > /* compare ref counts */ > for (i =3D 0, highest_cluster =3D 0; i < nb_clusters; i++) { > refcount1 =3D get_refcount(bs, i); > --=20 > 2.0.3 >=20 I tried during half an hour to find a git option (--patience etc) or a to= ol (Kompare) showing me that these code motions are right. The problem is that you extract subfunctions and move them up at the same= time. I will try again tomorow to find something making sense of this patch wit= hout having to spell check every single character. Best regards Beno=EEt