| Message ID | 1391881159-13585-3-git-send-email-mreitz@redhat.com |
|---|---|
| State | New |
| Headers | show |
Le Saturday 08 Feb 2014 à 18:39:13 (+0100), Max Reitz a écrit : > Allow bdrv_open() to handle references to existing block devices just as > bdrv_file_open() is already capable of. > > Signed-off-by: Max Reitz <mreitz@redhat.com> > --- > block.c | 41 ++++++++++++++++++++++++++++++++++------- > block/qcow2.c | 4 ++-- > block/vmdk.c | 3 ++- > block/vvfat.c | 2 +- > blockdev.c | 12 ++++++------ > hw/block/xen_disk.c | 4 ++-- > include/block/block.h | 5 +++-- > qemu-img.c | 8 ++++---- > qemu-io.c | 4 +++- > qemu-nbd.c | 2 +- > 10 files changed, 58 insertions(+), 27 deletions(-) > > diff --git a/block.c b/block.c > index 40a585a..3a32c37 100644 > --- a/block.c > +++ b/block.c > @@ -1040,7 +1040,7 @@ int bdrv_file_open(BlockDriverState **pbs, const char *filename, > } > > if (!drv->bdrv_file_open) { > - ret = bdrv_open(&bs, filename, options, flags, drv, &local_err); > + ret = bdrv_open(&bs, filename, NULL, options, flags, drv, &local_err); > options = NULL; > } else { > ret = bdrv_open_common(bs, NULL, options, flags, drv, &local_err); > @@ -1119,7 +1119,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) > > assert(bs->backing_hd == NULL); > ret = bdrv_open(&bs->backing_hd, > - *backing_filename ? backing_filename : NULL, options, > + *backing_filename ? backing_filename : NULL, NULL, options, > back_flags, back_drv, &local_err); > if (ret < 0) { > bs->backing_hd = NULL; > @@ -1199,7 +1199,7 @@ int bdrv_open_image(BlockDriverState **pbs, const char *filename, > goto done; > } > > - ret = bdrv_open(pbs, filename, image_options, flags, NULL, errp); > + ret = bdrv_open(pbs, filename, NULL, image_options, flags, NULL, errp); > } else { > ret = bdrv_file_open(pbs, filename, reference, image_options, flags, > errp); > @@ -1221,8 +1221,9 @@ done: > * If *pbs is NULL, a new BDS will be created with a pointer to it stored there. > * If it is not NULL, the referenced BDS will be reused. > */ > -int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, > - int flags, BlockDriver *drv, Error **errp) > +int bdrv_open(BlockDriverState **pbs, const char *filename, > + const char *reference, QDict *options, int flags, > + BlockDriver *drv, Error **errp) Maybe a little reference to the reference parameters in the comments would help ? Aside from that: Reviewed-by: Benoit Canet <benoit@irqsave.net> > { > int ret; > /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */ > @@ -1233,6 +1234,32 @@ int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, > > assert(pbs); > > + if (reference) { > + bool options_non_empty = options ? qdict_size(options) : false; > + QDECREF(options); > + > + if (*pbs) { > + error_setg(errp, "Cannot reuse an existing BDS when referencing " > + "another block device"); > + return -EINVAL; > + } > + > + if (filename || options_non_empty) { > + error_setg(errp, "Cannot reference an existing block device with " > + "additional options or a new filename"); > + return -EINVAL; > + } > + > + bs = bdrv_find(reference); > + if (!bs) { > + error_setg(errp, "Cannot find block device '%s'", reference); > + return -ENODEV; > + } > + bdrv_ref(bs); > + *pbs = bs; > + return 0; > + } > + > if (*pbs) { > bs = *pbs; > } else { > @@ -1260,7 +1287,7 @@ int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, > /* Get the required size from the image */ > QINCREF(options); > bs1 = NULL; > - ret = bdrv_open(&bs1, filename, options, BDRV_O_NO_BACKING, > + ret = bdrv_open(&bs1, filename, NULL, options, BDRV_O_NO_BACKING, > drv, &local_err); > if (ret < 0) { > goto fail; > @@ -5305,7 +5332,7 @@ void bdrv_img_create(const char *filename, const char *fmt, > flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); > > bs = NULL; > - ret = bdrv_open(&bs, backing_file->value.s, NULL, back_flags, > + ret = bdrv_open(&bs, backing_file->value.s, NULL, NULL, back_flags, > backing_drv, &local_err); > if (ret < 0) { > error_setg_errno(errp, -ret, "Could not open '%s': %s", > diff --git a/block/qcow2.c b/block/qcow2.c > index c8e8ba7..6996276 100644 > --- a/block/qcow2.c > +++ b/block/qcow2.c > @@ -1553,7 +1553,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, > */ > BlockDriver* drv = bdrv_find_format("qcow2"); > assert(drv != NULL); > - ret = bdrv_open(&bs, filename, NULL, > + ret = bdrv_open(&bs, filename, NULL, NULL, > BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv, &local_err); > if (ret < 0) { > error_propagate(errp, local_err); > @@ -1604,7 +1604,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, > bs = NULL; > > /* Reopen the image without BDRV_O_NO_FLUSH to flush it before returning */ > - ret = bdrv_open(&bs, filename, NULL, > + ret = bdrv_open(&bs, filename, NULL, NULL, > BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_BACKING, > drv, &local_err); > if (error_is_set(&local_err)) { > diff --git a/block/vmdk.c b/block/vmdk.c > index 52cd12a..e007793 100644 > --- a/block/vmdk.c > +++ b/block/vmdk.c > @@ -1756,7 +1756,8 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options, > } > if (backing_file) { > BlockDriverState *bs = NULL; > - ret = bdrv_open(&bs, backing_file, NULL, BDRV_O_NO_BACKING, NULL, errp); > + ret = bdrv_open(&bs, backing_file, NULL, NULL, BDRV_O_NO_BACKING, NULL, > + errp); > if (ret != 0) { > goto exit; > } > diff --git a/block/vvfat.c b/block/vvfat.c > index ae7bc6f..d7a830e 100644 > --- a/block/vvfat.c > +++ b/block/vvfat.c > @@ -2937,7 +2937,7 @@ static int enable_write_target(BDRVVVFATState *s) > } > > s->qcow = NULL; > - ret = bdrv_open(&s->qcow, s->qcow_filename, NULL, > + ret = bdrv_open(&s->qcow, s->qcow_filename, NULL, NULL, > BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, bdrv_qcow, > &local_err); > if (ret < 0) { > diff --git a/blockdev.c b/blockdev.c > index 6dd351c..7b7e349 100644 > --- a/blockdev.c > +++ b/blockdev.c > @@ -510,7 +510,7 @@ static DriveInfo *blockdev_init(const char *file, QDict *bs_opts, > bdrv_flags |= ro ? 0 : BDRV_O_RDWR; > > QINCREF(bs_opts); > - ret = bdrv_open(&dinfo->bdrv, file, bs_opts, bdrv_flags, drv, &error); > + ret = bdrv_open(&dinfo->bdrv, file, NULL, bs_opts, bdrv_flags, drv, &error); > > if (ret < 0) { > error_setg(errp, "could not open disk image %s: %s", > @@ -1304,7 +1304,7 @@ static void external_snapshot_prepare(BlkTransactionState *common, > /* TODO Inherit bs->options or only take explicit options with an > * extended QMP command? */ > assert(state->new_bs == NULL); > - ret = bdrv_open(&state->new_bs, new_image_file, options, > + ret = bdrv_open(&state->new_bs, new_image_file, NULL, options, > flags | BDRV_O_NO_BACKING, drv, &local_err); > /* We will manually add the backing_hd field to the bs later */ > if (ret != 0) { > @@ -1555,7 +1555,7 @@ static void qmp_bdrv_open_encrypted(BlockDriverState *bs, const char *filename, > Error *local_err = NULL; > int ret; > > - ret = bdrv_open(&bs, filename, NULL, bdrv_flags, drv, &local_err); > + ret = bdrv_open(&bs, filename, NULL, NULL, bdrv_flags, drv, &local_err); > if (ret < 0) { > error_propagate(errp, local_err); > return; > @@ -1992,7 +1992,7 @@ void qmp_drive_backup(const char *device, const char *target, > } > > target_bs = NULL; > - ret = bdrv_open(&target_bs, target, NULL, flags, drv, &local_err); > + ret = bdrv_open(&target_bs, target, NULL, NULL, flags, drv, &local_err); > if (ret < 0) { > error_propagate(errp, local_err); > return; > @@ -2135,8 +2135,8 @@ void qmp_drive_mirror(const char *device, const char *target, > * file. > */ > target_bs = NULL; > - ret = bdrv_open(&target_bs, target, NULL, flags | BDRV_O_NO_BACKING, drv, > - &local_err); > + ret = bdrv_open(&target_bs, target, NULL, NULL, flags | BDRV_O_NO_BACKING, > + drv, &local_err); > if (ret < 0) { > error_propagate(errp, local_err); > return; > diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c > index 14e6d0b..61e6ff3 100644 > --- a/hw/block/xen_disk.c > +++ b/hw/block/xen_disk.c > @@ -813,8 +813,8 @@ static int blk_connect(struct XenDevice *xendev) > Error *local_err = NULL; > BlockDriver *drv = bdrv_find_whitelisted_format(blkdev->fileproto, > readonly); > - if (bdrv_open(&blkdev->bs, > - blkdev->filename, NULL, qflags, drv, &local_err) != 0) > + if (bdrv_open(&blkdev->bs, blkdev->filename, NULL, NULL, qflags, > + drv, &local_err) != 0) > { > xen_be_printf(&blkdev->xendev, 0, "error: %s\n", > error_get_pretty(local_err)); > diff --git a/include/block/block.h b/include/block/block.h > index 980869d..a421041 100644 > --- a/include/block/block.h > +++ b/include/block/block.h > @@ -190,8 +190,9 @@ int bdrv_open_image(BlockDriverState **pbs, const char *filename, > QDict *options, const char *bdref_key, int flags, > bool force_raw, bool allow_none, Error **errp); > int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp); > -int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, > - int flags, BlockDriver *drv, Error **errp); > +int bdrv_open(BlockDriverState **pbs, const char *filename, > + const char *reference, QDict *options, int flags, > + BlockDriver *drv, Error **errp); > BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, > BlockDriverState *bs, int flags); > int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); > diff --git a/qemu-img.c b/qemu-img.c > index 897aa56..b834d52 100644 > --- a/qemu-img.c > +++ b/qemu-img.c > @@ -289,7 +289,7 @@ static BlockDriverState *bdrv_new_open(const char *filename, > drv = NULL; > } > > - ret = bdrv_open(&bs, filename, NULL, flags, drv, &local_err); > + ret = bdrv_open(&bs, filename, NULL, NULL, flags, drv, &local_err); > if (ret < 0) { > error_report("Could not open '%s': %s", filename, > error_get_pretty(local_err)); > @@ -2312,7 +2312,7 @@ static int img_rebase(int argc, char **argv) > > bs_old_backing = bdrv_new("old_backing"); > bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name)); > - ret = bdrv_open(&bs_old_backing, backing_name, NULL, BDRV_O_FLAGS, > + ret = bdrv_open(&bs_old_backing, backing_name, NULL, NULL, BDRV_O_FLAGS, > old_backing_drv, &local_err); > if (ret) { > error_report("Could not open old backing file '%s': %s", > @@ -2322,8 +2322,8 @@ static int img_rebase(int argc, char **argv) > } > if (out_baseimg[0]) { > bs_new_backing = bdrv_new("new_backing"); > - ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, BDRV_O_FLAGS, > - new_backing_drv, &local_err); > + ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, NULL, > + BDRV_O_FLAGS, new_backing_drv, &local_err); > if (ret) { > error_report("Could not open new backing file '%s': %s", > out_baseimg, error_get_pretty(local_err)); > diff --git a/qemu-io.c b/qemu-io.c > index 8da8f6e..61d54c0 100644 > --- a/qemu-io.c > +++ b/qemu-io.c > @@ -68,7 +68,9 @@ static int openfile(char *name, int flags, int growable, QDict *opts) > } else { > qemuio_bs = bdrv_new("hda"); > > - if (bdrv_open(&qemuio_bs, name, opts, flags, NULL, &local_err) < 0) { > + if (bdrv_open(&qemuio_bs, name, NULL, opts, flags, NULL, &local_err) > + < 0) > + { > fprintf(stderr, "%s: can't open device %s: %s\n", progname, name, > error_get_pretty(local_err)); > error_free(local_err); > diff --git a/qemu-nbd.c b/qemu-nbd.c > index 0cf123c..711162c 100644 > --- a/qemu-nbd.c > +++ b/qemu-nbd.c > @@ -597,7 +597,7 @@ int main(int argc, char **argv) > > bs = bdrv_new("hda"); > srcpath = argv[optind]; > - ret = bdrv_open(&bs, srcpath, NULL, flags, drv, &local_err); > + ret = bdrv_open(&bs, srcpath, NULL, NULL, flags, drv, &local_err); > if (ret < 0) { > errno = -ret; > err(EXIT_FAILURE, "Failed to bdrv_open '%s': %s", argv[optind], > -- > 1.8.5.4 > >
On 10.02.2014 14:30, Benoît Canet wrote: > Le Saturday 08 Feb 2014 à 18:39:13 (+0100), Max Reitz a écrit : >> Allow bdrv_open() to handle references to existing block devices just as >> bdrv_file_open() is already capable of. >> >> Signed-off-by: Max Reitz <mreitz@redhat.com> >> --- >> block.c | 41 ++++++++++++++++++++++++++++++++++------- >> block/qcow2.c | 4 ++-- >> block/vmdk.c | 3 ++- >> block/vvfat.c | 2 +- >> blockdev.c | 12 ++++++------ >> hw/block/xen_disk.c | 4 ++-- >> include/block/block.h | 5 +++-- >> qemu-img.c | 8 ++++---- >> qemu-io.c | 4 +++- >> qemu-nbd.c | 2 +- >> 10 files changed, 58 insertions(+), 27 deletions(-) >> >> diff --git a/block.c b/block.c >> index 40a585a..3a32c37 100644 >> --- a/block.c >> +++ b/block.c >> @@ -1040,7 +1040,7 @@ int bdrv_file_open(BlockDriverState **pbs, const char *filename, >> } >> >> if (!drv->bdrv_file_open) { >> - ret = bdrv_open(&bs, filename, options, flags, drv, &local_err); >> + ret = bdrv_open(&bs, filename, NULL, options, flags, drv, &local_err); >> options = NULL; >> } else { >> ret = bdrv_open_common(bs, NULL, options, flags, drv, &local_err); >> @@ -1119,7 +1119,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) >> >> assert(bs->backing_hd == NULL); >> ret = bdrv_open(&bs->backing_hd, >> - *backing_filename ? backing_filename : NULL, options, >> + *backing_filename ? backing_filename : NULL, NULL, options, >> back_flags, back_drv, &local_err); >> if (ret < 0) { >> bs->backing_hd = NULL; >> @@ -1199,7 +1199,7 @@ int bdrv_open_image(BlockDriverState **pbs, const char *filename, >> goto done; >> } >> >> - ret = bdrv_open(pbs, filename, image_options, flags, NULL, errp); >> + ret = bdrv_open(pbs, filename, NULL, image_options, flags, NULL, errp); >> } else { >> ret = bdrv_file_open(pbs, filename, reference, image_options, flags, >> errp); >> @@ -1221,8 +1221,9 @@ done: >> * If *pbs is NULL, a new BDS will be created with a pointer to it stored there. >> * If it is not NULL, the referenced BDS will be reused. >> */ >> -int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, >> - int flags, BlockDriver *drv, Error **errp) >> +int bdrv_open(BlockDriverState **pbs, const char *filename, >> + const char *reference, QDict *options, int flags, >> + BlockDriver *drv, Error **errp) > Maybe a little reference to the reference parameters in the comments would help > ? Yes, that would probably be helpful. Max > Aside from that: > > Reviewed-by: Benoit Canet <benoit@irqsave.net> > >> { >> int ret; >> /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */ >> @@ -1233,6 +1234,32 @@ int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, >> >> assert(pbs); >> >> + if (reference) { >> + bool options_non_empty = options ? qdict_size(options) : false; >> + QDECREF(options); >> + >> + if (*pbs) { >> + error_setg(errp, "Cannot reuse an existing BDS when referencing " >> + "another block device"); >> + return -EINVAL; >> + } >> + >> + if (filename || options_non_empty) { >> + error_setg(errp, "Cannot reference an existing block device with " >> + "additional options or a new filename"); >> + return -EINVAL; >> + } >> + >> + bs = bdrv_find(reference); >> + if (!bs) { >> + error_setg(errp, "Cannot find block device '%s'", reference); >> + return -ENODEV; >> + } >> + bdrv_ref(bs); >> + *pbs = bs; >> + return 0; >> + } >> + >> if (*pbs) { >> bs = *pbs; >> } else { >> @@ -1260,7 +1287,7 @@ int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, >> /* Get the required size from the image */ >> QINCREF(options); >> bs1 = NULL; >> - ret = bdrv_open(&bs1, filename, options, BDRV_O_NO_BACKING, >> + ret = bdrv_open(&bs1, filename, NULL, options, BDRV_O_NO_BACKING, >> drv, &local_err); >> if (ret < 0) { >> goto fail; >> @@ -5305,7 +5332,7 @@ void bdrv_img_create(const char *filename, const char *fmt, >> flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); >> >> bs = NULL; >> - ret = bdrv_open(&bs, backing_file->value.s, NULL, back_flags, >> + ret = bdrv_open(&bs, backing_file->value.s, NULL, NULL, back_flags, >> backing_drv, &local_err); >> if (ret < 0) { >> error_setg_errno(errp, -ret, "Could not open '%s': %s", >> diff --git a/block/qcow2.c b/block/qcow2.c >> index c8e8ba7..6996276 100644 >> --- a/block/qcow2.c >> +++ b/block/qcow2.c >> @@ -1553,7 +1553,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, >> */ >> BlockDriver* drv = bdrv_find_format("qcow2"); >> assert(drv != NULL); >> - ret = bdrv_open(&bs, filename, NULL, >> + ret = bdrv_open(&bs, filename, NULL, NULL, >> BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv, &local_err); >> if (ret < 0) { >> error_propagate(errp, local_err); >> @@ -1604,7 +1604,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, >> bs = NULL; >> >> /* Reopen the image without BDRV_O_NO_FLUSH to flush it before returning */ >> - ret = bdrv_open(&bs, filename, NULL, >> + ret = bdrv_open(&bs, filename, NULL, NULL, >> BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_BACKING, >> drv, &local_err); >> if (error_is_set(&local_err)) { >> diff --git a/block/vmdk.c b/block/vmdk.c >> index 52cd12a..e007793 100644 >> --- a/block/vmdk.c >> +++ b/block/vmdk.c >> @@ -1756,7 +1756,8 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options, >> } >> if (backing_file) { >> BlockDriverState *bs = NULL; >> - ret = bdrv_open(&bs, backing_file, NULL, BDRV_O_NO_BACKING, NULL, errp); >> + ret = bdrv_open(&bs, backing_file, NULL, NULL, BDRV_O_NO_BACKING, NULL, >> + errp); >> if (ret != 0) { >> goto exit; >> } >> diff --git a/block/vvfat.c b/block/vvfat.c >> index ae7bc6f..d7a830e 100644 >> --- a/block/vvfat.c >> +++ b/block/vvfat.c >> @@ -2937,7 +2937,7 @@ static int enable_write_target(BDRVVVFATState *s) >> } >> >> s->qcow = NULL; >> - ret = bdrv_open(&s->qcow, s->qcow_filename, NULL, >> + ret = bdrv_open(&s->qcow, s->qcow_filename, NULL, NULL, >> BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, bdrv_qcow, >> &local_err); >> if (ret < 0) { >> diff --git a/blockdev.c b/blockdev.c >> index 6dd351c..7b7e349 100644 >> --- a/blockdev.c >> +++ b/blockdev.c >> @@ -510,7 +510,7 @@ static DriveInfo *blockdev_init(const char *file, QDict *bs_opts, >> bdrv_flags |= ro ? 0 : BDRV_O_RDWR; >> >> QINCREF(bs_opts); >> - ret = bdrv_open(&dinfo->bdrv, file, bs_opts, bdrv_flags, drv, &error); >> + ret = bdrv_open(&dinfo->bdrv, file, NULL, bs_opts, bdrv_flags, drv, &error); >> >> if (ret < 0) { >> error_setg(errp, "could not open disk image %s: %s", >> @@ -1304,7 +1304,7 @@ static void external_snapshot_prepare(BlkTransactionState *common, >> /* TODO Inherit bs->options or only take explicit options with an >> * extended QMP command? */ >> assert(state->new_bs == NULL); >> - ret = bdrv_open(&state->new_bs, new_image_file, options, >> + ret = bdrv_open(&state->new_bs, new_image_file, NULL, options, >> flags | BDRV_O_NO_BACKING, drv, &local_err); >> /* We will manually add the backing_hd field to the bs later */ >> if (ret != 0) { >> @@ -1555,7 +1555,7 @@ static void qmp_bdrv_open_encrypted(BlockDriverState *bs, const char *filename, >> Error *local_err = NULL; >> int ret; >> >> - ret = bdrv_open(&bs, filename, NULL, bdrv_flags, drv, &local_err); >> + ret = bdrv_open(&bs, filename, NULL, NULL, bdrv_flags, drv, &local_err); >> if (ret < 0) { >> error_propagate(errp, local_err); >> return; >> @@ -1992,7 +1992,7 @@ void qmp_drive_backup(const char *device, const char *target, >> } >> >> target_bs = NULL; >> - ret = bdrv_open(&target_bs, target, NULL, flags, drv, &local_err); >> + ret = bdrv_open(&target_bs, target, NULL, NULL, flags, drv, &local_err); >> if (ret < 0) { >> error_propagate(errp, local_err); >> return; >> @@ -2135,8 +2135,8 @@ void qmp_drive_mirror(const char *device, const char *target, >> * file. >> */ >> target_bs = NULL; >> - ret = bdrv_open(&target_bs, target, NULL, flags | BDRV_O_NO_BACKING, drv, >> - &local_err); >> + ret = bdrv_open(&target_bs, target, NULL, NULL, flags | BDRV_O_NO_BACKING, >> + drv, &local_err); >> if (ret < 0) { >> error_propagate(errp, local_err); >> return; >> diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c >> index 14e6d0b..61e6ff3 100644 >> --- a/hw/block/xen_disk.c >> +++ b/hw/block/xen_disk.c >> @@ -813,8 +813,8 @@ static int blk_connect(struct XenDevice *xendev) >> Error *local_err = NULL; >> BlockDriver *drv = bdrv_find_whitelisted_format(blkdev->fileproto, >> readonly); >> - if (bdrv_open(&blkdev->bs, >> - blkdev->filename, NULL, qflags, drv, &local_err) != 0) >> + if (bdrv_open(&blkdev->bs, blkdev->filename, NULL, NULL, qflags, >> + drv, &local_err) != 0) >> { >> xen_be_printf(&blkdev->xendev, 0, "error: %s\n", >> error_get_pretty(local_err)); >> diff --git a/include/block/block.h b/include/block/block.h >> index 980869d..a421041 100644 >> --- a/include/block/block.h >> +++ b/include/block/block.h >> @@ -190,8 +190,9 @@ int bdrv_open_image(BlockDriverState **pbs, const char *filename, >> QDict *options, const char *bdref_key, int flags, >> bool force_raw, bool allow_none, Error **errp); >> int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp); >> -int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, >> - int flags, BlockDriver *drv, Error **errp); >> +int bdrv_open(BlockDriverState **pbs, const char *filename, >> + const char *reference, QDict *options, int flags, >> + BlockDriver *drv, Error **errp); >> BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, >> BlockDriverState *bs, int flags); >> int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); >> diff --git a/qemu-img.c b/qemu-img.c >> index 897aa56..b834d52 100644 >> --- a/qemu-img.c >> +++ b/qemu-img.c >> @@ -289,7 +289,7 @@ static BlockDriverState *bdrv_new_open(const char *filename, >> drv = NULL; >> } >> >> - ret = bdrv_open(&bs, filename, NULL, flags, drv, &local_err); >> + ret = bdrv_open(&bs, filename, NULL, NULL, flags, drv, &local_err); >> if (ret < 0) { >> error_report("Could not open '%s': %s", filename, >> error_get_pretty(local_err)); >> @@ -2312,7 +2312,7 @@ static int img_rebase(int argc, char **argv) >> >> bs_old_backing = bdrv_new("old_backing"); >> bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name)); >> - ret = bdrv_open(&bs_old_backing, backing_name, NULL, BDRV_O_FLAGS, >> + ret = bdrv_open(&bs_old_backing, backing_name, NULL, NULL, BDRV_O_FLAGS, >> old_backing_drv, &local_err); >> if (ret) { >> error_report("Could not open old backing file '%s': %s", >> @@ -2322,8 +2322,8 @@ static int img_rebase(int argc, char **argv) >> } >> if (out_baseimg[0]) { >> bs_new_backing = bdrv_new("new_backing"); >> - ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, BDRV_O_FLAGS, >> - new_backing_drv, &local_err); >> + ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, NULL, >> + BDRV_O_FLAGS, new_backing_drv, &local_err); >> if (ret) { >> error_report("Could not open new backing file '%s': %s", >> out_baseimg, error_get_pretty(local_err)); >> diff --git a/qemu-io.c b/qemu-io.c >> index 8da8f6e..61d54c0 100644 >> --- a/qemu-io.c >> +++ b/qemu-io.c >> @@ -68,7 +68,9 @@ static int openfile(char *name, int flags, int growable, QDict *opts) >> } else { >> qemuio_bs = bdrv_new("hda"); >> >> - if (bdrv_open(&qemuio_bs, name, opts, flags, NULL, &local_err) < 0) { >> + if (bdrv_open(&qemuio_bs, name, NULL, opts, flags, NULL, &local_err) >> + < 0) >> + { >> fprintf(stderr, "%s: can't open device %s: %s\n", progname, name, >> error_get_pretty(local_err)); >> error_free(local_err); >> diff --git a/qemu-nbd.c b/qemu-nbd.c >> index 0cf123c..711162c 100644 >> --- a/qemu-nbd.c >> +++ b/qemu-nbd.c >> @@ -597,7 +597,7 @@ int main(int argc, char **argv) >> >> bs = bdrv_new("hda"); >> srcpath = argv[optind]; >> - ret = bdrv_open(&bs, srcpath, NULL, flags, drv, &local_err); >> + ret = bdrv_open(&bs, srcpath, NULL, NULL, flags, drv, &local_err); >> if (ret < 0) { >> errno = -ret; >> err(EXIT_FAILURE, "Failed to bdrv_open '%s': %s", argv[optind], >> -- >> 1.8.5.4 >> >>
diff --git a/block.c b/block.c index 40a585a..3a32c37 100644 --- a/block.c +++ b/block.c @@ -1040,7 +1040,7 @@ int bdrv_file_open(BlockDriverState **pbs, const char *filename, } if (!drv->bdrv_file_open) { - ret = bdrv_open(&bs, filename, options, flags, drv, &local_err); + ret = bdrv_open(&bs, filename, NULL, options, flags, drv, &local_err); options = NULL; } else { ret = bdrv_open_common(bs, NULL, options, flags, drv, &local_err); @@ -1119,7 +1119,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) assert(bs->backing_hd == NULL); ret = bdrv_open(&bs->backing_hd, - *backing_filename ? backing_filename : NULL, options, + *backing_filename ? backing_filename : NULL, NULL, options, back_flags, back_drv, &local_err); if (ret < 0) { bs->backing_hd = NULL; @@ -1199,7 +1199,7 @@ int bdrv_open_image(BlockDriverState **pbs, const char *filename, goto done; } - ret = bdrv_open(pbs, filename, image_options, flags, NULL, errp); + ret = bdrv_open(pbs, filename, NULL, image_options, flags, NULL, errp); } else { ret = bdrv_file_open(pbs, filename, reference, image_options, flags, errp); @@ -1221,8 +1221,9 @@ done: * If *pbs is NULL, a new BDS will be created with a pointer to it stored there. * If it is not NULL, the referenced BDS will be reused. */ -int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, - int flags, BlockDriver *drv, Error **errp) +int bdrv_open(BlockDriverState **pbs, const char *filename, + const char *reference, QDict *options, int flags, + BlockDriver *drv, Error **errp) { int ret; /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */ @@ -1233,6 +1234,32 @@ int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, assert(pbs); + if (reference) { + bool options_non_empty = options ? qdict_size(options) : false; + QDECREF(options); + + if (*pbs) { + error_setg(errp, "Cannot reuse an existing BDS when referencing " + "another block device"); + return -EINVAL; + } + + if (filename || options_non_empty) { + error_setg(errp, "Cannot reference an existing block device with " + "additional options or a new filename"); + return -EINVAL; + } + + bs = bdrv_find(reference); + if (!bs) { + error_setg(errp, "Cannot find block device '%s'", reference); + return -ENODEV; + } + bdrv_ref(bs); + *pbs = bs; + return 0; + } + if (*pbs) { bs = *pbs; } else { @@ -1260,7 +1287,7 @@ int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, /* Get the required size from the image */ QINCREF(options); bs1 = NULL; - ret = bdrv_open(&bs1, filename, options, BDRV_O_NO_BACKING, + ret = bdrv_open(&bs1, filename, NULL, options, BDRV_O_NO_BACKING, drv, &local_err); if (ret < 0) { goto fail; @@ -5305,7 +5332,7 @@ void bdrv_img_create(const char *filename, const char *fmt, flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); bs = NULL; - ret = bdrv_open(&bs, backing_file->value.s, NULL, back_flags, + ret = bdrv_open(&bs, backing_file->value.s, NULL, NULL, back_flags, backing_drv, &local_err); if (ret < 0) { error_setg_errno(errp, -ret, "Could not open '%s': %s", diff --git a/block/qcow2.c b/block/qcow2.c index c8e8ba7..6996276 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1553,7 +1553,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, */ BlockDriver* drv = bdrv_find_format("qcow2"); assert(drv != NULL); - ret = bdrv_open(&bs, filename, NULL, + ret = bdrv_open(&bs, filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv, &local_err); if (ret < 0) { error_propagate(errp, local_err); @@ -1604,7 +1604,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, bs = NULL; /* Reopen the image without BDRV_O_NO_FLUSH to flush it before returning */ - ret = bdrv_open(&bs, filename, NULL, + ret = bdrv_open(&bs, filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_BACKING, drv, &local_err); if (error_is_set(&local_err)) { diff --git a/block/vmdk.c b/block/vmdk.c index 52cd12a..e007793 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -1756,7 +1756,8 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options, } if (backing_file) { BlockDriverState *bs = NULL; - ret = bdrv_open(&bs, backing_file, NULL, BDRV_O_NO_BACKING, NULL, errp); + ret = bdrv_open(&bs, backing_file, NULL, NULL, BDRV_O_NO_BACKING, NULL, + errp); if (ret != 0) { goto exit; } diff --git a/block/vvfat.c b/block/vvfat.c index ae7bc6f..d7a830e 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -2937,7 +2937,7 @@ static int enable_write_target(BDRVVVFATState *s) } s->qcow = NULL; - ret = bdrv_open(&s->qcow, s->qcow_filename, NULL, + ret = bdrv_open(&s->qcow, s->qcow_filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, bdrv_qcow, &local_err); if (ret < 0) { diff --git a/blockdev.c b/blockdev.c index 6dd351c..7b7e349 100644 --- a/blockdev.c +++ b/blockdev.c @@ -510,7 +510,7 @@ static DriveInfo *blockdev_init(const char *file, QDict *bs_opts, bdrv_flags |= ro ? 0 : BDRV_O_RDWR; QINCREF(bs_opts); - ret = bdrv_open(&dinfo->bdrv, file, bs_opts, bdrv_flags, drv, &error); + ret = bdrv_open(&dinfo->bdrv, file, NULL, bs_opts, bdrv_flags, drv, &error); if (ret < 0) { error_setg(errp, "could not open disk image %s: %s", @@ -1304,7 +1304,7 @@ static void external_snapshot_prepare(BlkTransactionState *common, /* TODO Inherit bs->options or only take explicit options with an * extended QMP command? */ assert(state->new_bs == NULL); - ret = bdrv_open(&state->new_bs, new_image_file, options, + ret = bdrv_open(&state->new_bs, new_image_file, NULL, options, flags | BDRV_O_NO_BACKING, drv, &local_err); /* We will manually add the backing_hd field to the bs later */ if (ret != 0) { @@ -1555,7 +1555,7 @@ static void qmp_bdrv_open_encrypted(BlockDriverState *bs, const char *filename, Error *local_err = NULL; int ret; - ret = bdrv_open(&bs, filename, NULL, bdrv_flags, drv, &local_err); + ret = bdrv_open(&bs, filename, NULL, NULL, bdrv_flags, drv, &local_err); if (ret < 0) { error_propagate(errp, local_err); return; @@ -1992,7 +1992,7 @@ void qmp_drive_backup(const char *device, const char *target, } target_bs = NULL; - ret = bdrv_open(&target_bs, target, NULL, flags, drv, &local_err); + ret = bdrv_open(&target_bs, target, NULL, NULL, flags, drv, &local_err); if (ret < 0) { error_propagate(errp, local_err); return; @@ -2135,8 +2135,8 @@ void qmp_drive_mirror(const char *device, const char *target, * file. */ target_bs = NULL; - ret = bdrv_open(&target_bs, target, NULL, flags | BDRV_O_NO_BACKING, drv, - &local_err); + ret = bdrv_open(&target_bs, target, NULL, NULL, flags | BDRV_O_NO_BACKING, + drv, &local_err); if (ret < 0) { error_propagate(errp, local_err); return; diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c index 14e6d0b..61e6ff3 100644 --- a/hw/block/xen_disk.c +++ b/hw/block/xen_disk.c @@ -813,8 +813,8 @@ static int blk_connect(struct XenDevice *xendev) Error *local_err = NULL; BlockDriver *drv = bdrv_find_whitelisted_format(blkdev->fileproto, readonly); - if (bdrv_open(&blkdev->bs, - blkdev->filename, NULL, qflags, drv, &local_err) != 0) + if (bdrv_open(&blkdev->bs, blkdev->filename, NULL, NULL, qflags, + drv, &local_err) != 0) { xen_be_printf(&blkdev->xendev, 0, "error: %s\n", error_get_pretty(local_err)); diff --git a/include/block/block.h b/include/block/block.h index 980869d..a421041 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -190,8 +190,9 @@ int bdrv_open_image(BlockDriverState **pbs, const char *filename, QDict *options, const char *bdref_key, int flags, bool force_raw, bool allow_none, Error **errp); int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp); -int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, - int flags, BlockDriver *drv, Error **errp); +int bdrv_open(BlockDriverState **pbs, const char *filename, + const char *reference, QDict *options, int flags, + BlockDriver *drv, Error **errp); BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, BlockDriverState *bs, int flags); int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); diff --git a/qemu-img.c b/qemu-img.c index 897aa56..b834d52 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -289,7 +289,7 @@ static BlockDriverState *bdrv_new_open(const char *filename, drv = NULL; } - ret = bdrv_open(&bs, filename, NULL, flags, drv, &local_err); + ret = bdrv_open(&bs, filename, NULL, NULL, flags, drv, &local_err); if (ret < 0) { error_report("Could not open '%s': %s", filename, error_get_pretty(local_err)); @@ -2312,7 +2312,7 @@ static int img_rebase(int argc, char **argv) bs_old_backing = bdrv_new("old_backing"); bdrv_get_backing_filename(bs, backing_name, sizeof(backing_name)); - ret = bdrv_open(&bs_old_backing, backing_name, NULL, BDRV_O_FLAGS, + ret = bdrv_open(&bs_old_backing, backing_name, NULL, NULL, BDRV_O_FLAGS, old_backing_drv, &local_err); if (ret) { error_report("Could not open old backing file '%s': %s", @@ -2322,8 +2322,8 @@ static int img_rebase(int argc, char **argv) } if (out_baseimg[0]) { bs_new_backing = bdrv_new("new_backing"); - ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, BDRV_O_FLAGS, - new_backing_drv, &local_err); + ret = bdrv_open(&bs_new_backing, out_baseimg, NULL, NULL, + BDRV_O_FLAGS, new_backing_drv, &local_err); if (ret) { error_report("Could not open new backing file '%s': %s", out_baseimg, error_get_pretty(local_err)); diff --git a/qemu-io.c b/qemu-io.c index 8da8f6e..61d54c0 100644 --- a/qemu-io.c +++ b/qemu-io.c @@ -68,7 +68,9 @@ static int openfile(char *name, int flags, int growable, QDict *opts) } else { qemuio_bs = bdrv_new("hda"); - if (bdrv_open(&qemuio_bs, name, opts, flags, NULL, &local_err) < 0) { + if (bdrv_open(&qemuio_bs, name, NULL, opts, flags, NULL, &local_err) + < 0) + { fprintf(stderr, "%s: can't open device %s: %s\n", progname, name, error_get_pretty(local_err)); error_free(local_err); diff --git a/qemu-nbd.c b/qemu-nbd.c index 0cf123c..711162c 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -597,7 +597,7 @@ int main(int argc, char **argv) bs = bdrv_new("hda"); srcpath = argv[optind]; - ret = bdrv_open(&bs, srcpath, NULL, flags, drv, &local_err); + ret = bdrv_open(&bs, srcpath, NULL, NULL, flags, drv, &local_err); if (ret < 0) { errno = -ret; err(EXIT_FAILURE, "Failed to bdrv_open '%s': %s", argv[optind],
Allow bdrv_open() to handle references to existing block devices just as bdrv_file_open() is already capable of. Signed-off-by: Max Reitz <mreitz@redhat.com> --- block.c | 41 ++++++++++++++++++++++++++++++++++------- block/qcow2.c | 4 ++-- block/vmdk.c | 3 ++- block/vvfat.c | 2 +- blockdev.c | 12 ++++++------ hw/block/xen_disk.c | 4 ++-- include/block/block.h | 5 +++-- qemu-img.c | 8 ++++---- qemu-io.c | 4 +++- qemu-nbd.c | 2 +- 10 files changed, 58 insertions(+), 27 deletions(-)