From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42580) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bKSdU-0001II-Q0 for qemu-devel@nongnu.org; Tue, 05 Jul 2016 11:51:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bKSdT-0006fy-BE for qemu-devel@nongnu.org; Tue, 05 Jul 2016 11:51:44 -0400 From: Kevin Wolf Date: Tue, 5 Jul 2016 17:50:35 +0200 Message-Id: <1467733852-27097-27-git-send-email-kwolf@redhat.com> In-Reply-To: <1467733852-27097-1-git-send-email-kwolf@redhat.com> References: <1467733852-27097-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 26/43] vvfat: Use BdrvChild for s->qcow List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org vvfat uses a temporary qcow file to cache written data in read-write mode. In order to do things properly, this should show up in the BDS graph and I/O should go through BdrvChild like for every other node. Signed-off-by: Kevin Wolf Acked-by: Stefan Hajnoczi --- block/vvfat.c | 66 ++++++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 43 insertions(+), 23 deletions(-) diff --git a/block/vvfat.c b/block/vvfat.c index 55b5759..be9036e 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -341,9 +341,8 @@ typedef struct BDRVVVFATState { unsigned int current_cluster; /* write support */ - BlockDriverState* write_target; char* qcow_filename; - BlockDriverState* qcow; + BdrvChild* qcow; void* fat2; char* used_clusters; array_t commits; @@ -981,7 +980,7 @@ static int init_directories(BDRVVVFATState* s, static BDRVVVFATState *vvv = NULL; #endif -static int enable_write_target(BDRVVVFATState *s, Error **errp); +static int enable_write_target(BlockDriverState *bs, Error **errp); static int is_consistent(BDRVVVFATState *s); static QemuOptsList runtime_opts = { @@ -1159,7 +1158,7 @@ static int vvfat_open(BlockDriverState *bs, QDict *options, int flags, /* read only is the default for safety */ bs->read_only = true; - s->qcow = s->write_target = NULL; + s->qcow = NULL; s->qcow_filename = NULL; s->fat2 = NULL; s->downcase_short_names = 1; @@ -1170,7 +1169,7 @@ static int vvfat_open(BlockDriverState *bs, QDict *options, int flags, s->sector_count = cyls * heads * secs - (s->first_sectors_number - 1); if (qemu_opt_get_bool(opts, "rw", false)) { - ret = enable_write_target(s, errp); + ret = enable_write_target(bs, errp); if (ret < 0) { goto fail; } @@ -1391,9 +1390,10 @@ static int vvfat_read(BlockDriverState *bs, int64_t sector_num, return -1; if (s->qcow) { int n; - if (bdrv_is_allocated(s->qcow, sector_num, nb_sectors-i, &n)) { -DLOG(fprintf(stderr, "sectors %d+%d allocated\n", (int)sector_num, n)); - if (bdrv_read(s->qcow, sector_num, buf + i*0x200, n)) { + if (bdrv_is_allocated(s->qcow->bs, sector_num, nb_sectors-i, &n)) { + DLOG(fprintf(stderr, "sectors %d+%d allocated\n", + (int)sector_num, n)); + if (bdrv_read(s->qcow->bs, sector_num, buf + i * 0x200, n)) { return -1; } i += n - 1; @@ -1669,12 +1669,15 @@ static inline int cluster_was_modified(BDRVVVFATState* s, uint32_t cluster_num) int was_modified = 0; int i, dummy; - if (s->qcow == NULL) - return 0; + if (s->qcow == NULL) { + return 0; + } - for (i = 0; !was_modified && i < s->sectors_per_cluster; i++) - was_modified = bdrv_is_allocated(s->qcow, - cluster2sector(s, cluster_num) + i, 1, &dummy); + for (i = 0; !was_modified && i < s->sectors_per_cluster; i++) { + was_modified = bdrv_is_allocated(s->qcow->bs, + cluster2sector(s, cluster_num) + i, + 1, &dummy); + } return was_modified; } @@ -1823,11 +1826,17 @@ static uint32_t get_cluster_count_for_direntry(BDRVVVFATState* s, vvfat_close_current_file(s); for (i = 0; i < s->sectors_per_cluster; i++) { - if (!bdrv_is_allocated(s->qcow, offset + i, 1, &dummy)) { - if (vvfat_read(s->bs, offset, s->cluster_buffer, 1)) { + int res; + + res = bdrv_is_allocated(s->qcow->bs, offset + i, 1, &dummy); + if (!res) { + res = vvfat_read(s->bs, offset, s->cluster_buffer, 1); + if (res) { return -1; } - if (bdrv_write(s->qcow, offset, s->cluster_buffer, 1)) { + res = bdrv_write(s->qcow->bs, offset, + s->cluster_buffer, 1); + if (res) { return -2; } } @@ -2783,8 +2792,8 @@ static int do_commit(BDRVVVFATState* s) return ret; } - if (s->qcow->drv->bdrv_make_empty) { - s->qcow->drv->bdrv_make_empty(s->qcow); + if (s->qcow->bs->drv->bdrv_make_empty) { + s->qcow->bs->drv->bdrv_make_empty(s->qcow->bs); } memset(s->used_clusters, 0, sector2cluster(s, s->sector_count)); @@ -2880,7 +2889,7 @@ DLOG(checkpoint()); * Use qcow backend. Commit later. */ DLOG(fprintf(stderr, "Write to qcow backend: %d + %d\n", (int)sector_num, nb_sectors)); - ret = bdrv_write(s->qcow, sector_num, buf, nb_sectors); + ret = bdrv_write(s->qcow->bs, sector_num, buf, nb_sectors); if (ret < 0) { fprintf(stderr, "Error writing to qcow backend\n"); return ret; @@ -2950,7 +2959,7 @@ write_target_commit(BlockDriverState *bs, uint64_t offset, uint64_t bytes, static void write_target_close(BlockDriverState *bs) { BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque); - bdrv_unref(s->qcow); + bdrv_unref_child(s->bs, s->qcow); g_free(s->qcow_filename); } @@ -2960,8 +2969,19 @@ static BlockDriver vvfat_write_target = { .bdrv_close = write_target_close, }; -static int enable_write_target(BDRVVVFATState *s, Error **errp) +static void vvfat_qcow_options(int *child_flags, QDict *child_options, + int parent_flags, QDict *parent_options) { + *child_flags = BDRV_O_RDWR | BDRV_O_NO_FLUSH; +} + +static const BdrvChildRole child_vvfat_qcow = { + .inherit_options = vvfat_qcow_options, +}; + +static int enable_write_target(BlockDriverState *bs, Error **errp) +{ + BDRVVVFATState *s = bs->opaque; BlockDriver *bdrv_qcow = NULL; BlockDriverState *backing; QemuOpts *opts = NULL; @@ -3000,8 +3020,8 @@ static int enable_write_target(BDRVVVFATState *s, Error **errp) options = qdict_new(); qdict_put(options, "driver", qstring_from_str("qcow")); - s->qcow = bdrv_open(s->qcow_filename, NULL, options, - BDRV_O_RDWR | BDRV_O_NO_FLUSH, errp); + s->qcow = bdrv_open_child(s->qcow_filename, options, "write-target", bs, + &child_vvfat_qcow, false, errp); if (!s->qcow) { ret = -EINVAL; goto err; -- 1.8.3.1