From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49112) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W7c5p-0000dq-I6 for qemu-devel@nongnu.org; Sun, 26 Jan 2014 21:38:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W7c5j-0007Wj-Eh for qemu-devel@nongnu.org; Sun, 26 Jan 2014 21:38:33 -0500 Received: from paradis.irqsave.net ([62.212.105.220]:48406) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W7c5i-0007Wf-EY for qemu-devel@nongnu.org; Sun, 26 Jan 2014 21:38:27 -0500 Date: Mon, 27 Jan 2014 03:38:25 +0100 From: =?iso-8859-1?Q?Beno=EEt?= Canet Message-ID: <20140127023825.GA7415@irqsave.net> References: <1390762963-25538-1-git-send-email-mreitz@redhat.com> <1390762963-25538-2-git-send-email-mreitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1390762963-25538-2-git-send-email-mreitz@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 01/10] block: Change BDS parameter of bdrv_open() to ** List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz Cc: Kevin Wolf , qemu-devel@nongnu.org, Stefan Hajnoczi Le Sunday 26 Jan 2014 =E0 20:02:34 (+0100), Max Reitz a =E9crit : > Make bdrv_open() take a pointer to a BDS pointer, similarly to > bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open() > will create a new BDS with an empty name; if the BDS pointer is not > NULL, that existing BDS will be reused (in the same way as bdrv_open() > already did). >=20 > Signed-off-by: Max Reitz > --- > block.c | 53 ++++++++++++++++++++++++++-----------------= -------- > block/qcow2.c | 14 +++++++++----- > block/vmdk.c | 5 ++--- > block/vvfat.c | 6 ++---- > blockdev.c | 21 ++++++++------------ > hw/block/xen_disk.c | 2 +- > include/block/block.h | 2 +- > qemu-img.c | 6 +++--- > qemu-io.c | 2 +- > qemu-nbd.c | 2 +- > 10 files changed, 55 insertions(+), 58 deletions(-) >=20 > diff --git a/block.c b/block.c > index cb21a5f..c660609 100644 > --- a/block.c > +++ b/block.c > @@ -1039,7 +1039,7 @@ int bdrv_file_open(BlockDriverState **pbs, const = char *filename, > } > =20 > if (!drv->bdrv_file_open) { > - ret =3D bdrv_open(bs, filename, options, flags, drv, &local_er= r); > + ret =3D bdrv_open(&bs, filename, options, flags, drv, &local_e= rr); > options =3D NULL; > } else { > ret =3D bdrv_open_common(bs, NULL, options, flags, drv, &local= _err); > @@ -1108,8 +1108,6 @@ int bdrv_open_backing_file(BlockDriverState *bs, = QDict *options, Error **errp) > sizeof(backing_filename)); > } > =20 > - bs->backing_hd =3D bdrv_new(""); > - > if (bs->backing_format[0] !=3D '\0') { > back_drv =3D bdrv_find_format(bs->backing_format); > } > @@ -1118,11 +1116,10 @@ int bdrv_open_backing_file(BlockDriverState *bs= , QDict *options, Error **errp) > back_flags =3D bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | > BDRV_O_COPY_ON_READ); > =20 > - ret =3D bdrv_open(bs->backing_hd, > + ret =3D bdrv_open(&bs->backing_hd, > *backing_filename ? backing_filename : NULL, optio= ns, > back_flags, back_drv, &local_err); > if (ret < 0) { > - bdrv_unref(bs->backing_hd); > bs->backing_hd =3D NULL; > bs->open_flags |=3D BDRV_O_NO_BACKING; > error_setg(errp, "Could not open backing file: %s", > @@ -1189,8 +1186,6 @@ int bdrv_open_image(BlockDriverState **pbs, const= char *filename, > /* If a filename is given and the block driver should be detec= ted > automatically (instead of using none), use bdrv_open() in o= rder to do > that auto-detection. */ > - BlockDriverState *bs; > - > if (reference) { > error_setg(errp, "Cannot reference an existing block devic= e while " > "giving a filename"); > @@ -1198,13 +1193,8 @@ int bdrv_open_image(BlockDriverState **pbs, cons= t char *filename, > goto done; > } > =20 > - bs =3D bdrv_new(""); > - ret =3D bdrv_open(bs, filename, image_options, flags, NULL, er= rp); > - if (ret < 0) { > - bdrv_unref(bs); > - } else { > - *pbs =3D bs; > - } > + *pbs =3D NULL; bdrv_open set *file =3D NULL before calling bdrv_open_image so this is re= dundant. What would be the correct behavior if the caller was giving *pbs !=3D NUL= L ? Is loosing the reference to a previously existing bds right ? > + ret =3D bdrv_open(pbs, filename, image_options, flags, NULL, e= rrp); > } else { > ret =3D bdrv_file_open(pbs, filename, reference, image_options= , flags, > errp); > @@ -1222,14 +1212,17 @@ done: > * empty set of options. The reference to the QDict belongs to the blo= ck layer > * after the call (even on failure), so if the caller intends to reuse= the > * dictionary, it needs to use QINCREF() before calling bdrv_open. > + * > + * If *pbs is NULL, a new BDS will be created with a pointer to it sto= red there. > + * If it is not NULL, the referenced BDS will be reused. > */ > -int bdrv_open(BlockDriverState *bs, const char *filename, QDict *optio= ns, > +int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *opt= ions, > int flags, BlockDriver *drv, Error **errp) > { > int ret; > /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows.= */ > char tmp_filename[PATH_MAX + 1]; > - BlockDriverState *file =3D NULL; > + BlockDriverState *file =3D NULL, *bs =3D NULL; > const char *drvname; > Error *local_err =3D NULL; > =20 > @@ -1238,12 +1231,17 @@ int bdrv_open(BlockDriverState *bs, const char = *filename, QDict *options, > options =3D qdict_new(); > } > =20 > + if (*pbs) { > + bs =3D *pbs; > + } else { > + bs =3D bdrv_new(""); > + } > bs->options =3D options; > options =3D qdict_clone_shallow(options); > =20 > /* For snapshot=3Don, create a temporary qcow2 overlay */ > if (flags & BDRV_O_SNAPSHOT) { > - BlockDriverState *bs1; > + BlockDriverState *bs1 =3D NULL; > int64_t total_size; > BlockDriver *bdrv_qcow2; > QEMUOptionParameter *create_options; > @@ -1253,12 +1251,10 @@ int bdrv_open(BlockDriverState *bs, const char = *filename, QDict *options, > instead of opening 'filename' directly */ > =20 > /* Get the required size from the image */ > - bs1 =3D bdrv_new(""); > QINCREF(options); > - ret =3D bdrv_open(bs1, filename, options, BDRV_O_NO_BACKING, > + ret =3D bdrv_open(&bs1, filename, options, BDRV_O_NO_BACKING, > drv, &local_err); > if (ret < 0) { > - bdrv_unref(bs1); > goto fail; > } > total_size =3D bdrv_getlength(bs1) & BDRV_SECTOR_MASK; > @@ -1386,6 +1382,7 @@ int bdrv_open(BlockDriverState *bs, const char *f= ilename, QDict *options, > bdrv_dev_change_media_cb(bs, true); > } > =20 > + *pbs =3D bs; > return 0; > =20 > unlink_and_fail: The goto chain is different on Kevin qemu.git block; there is an addition= al fail label ? On which tree and branch are these patches based ? > @@ -1399,13 +1396,20 @@ fail: > QDECREF(bs->options); > QDECREF(options); > bs->options =3D NULL; > + if (!*pbs) { > + bdrv_unref(bs); > + } > if (error_is_set(&local_err)) { > error_propagate(errp, local_err); > } > return ret; > =20 > close_and_fail: > - bdrv_close(bs); > + if (*pbs) { > + bdrv_close(bs); > + } else { > + bdrv_unref(bs); > + } > QDECREF(options); > if (error_is_set(&local_err)) { > error_propagate(errp, local_err); > @@ -5276,7 +5280,7 @@ void bdrv_img_create(const char *filename, const = char *fmt, > size =3D get_option_parameter(param, BLOCK_OPT_SIZE); > if (size && size->value.n =3D=3D -1) { > if (backing_file && backing_file->value.s) { > - BlockDriverState *bs; > + BlockDriverState *bs =3D NULL; > uint64_t size; > char buf[32]; > int back_flags; > @@ -5285,9 +5289,7 @@ void bdrv_img_create(const char *filename, const = char *fmt, > back_flags =3D > flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BA= CKING); > =20 > - bs =3D bdrv_new(""); > - > - ret =3D bdrv_open(bs, backing_file->value.s, NULL, back_fl= ags, > + ret =3D bdrv_open(&bs, backing_file->value.s, NULL, back_f= lags, > backing_drv, &local_err); > if (ret < 0) { > error_setg_errno(errp, -ret, "Could not open '%s': %s"= , > @@ -5295,7 +5297,6 @@ void bdrv_img_create(const char *filename, const = char *fmt, > error_get_pretty(local_err)); > error_free(local_err); > local_err =3D NULL; > - bdrv_unref(bs); > goto out; > } > bdrv_get_geometry(bs, &size); > diff --git a/block/qcow2.c b/block/qcow2.c > index 2da62b8..9a25fbd 100644 > --- a/block/qcow2.c > +++ b/block/qcow2.c > @@ -1541,7 +1541,8 @@ static int qcow2_create2(const char *filename, in= t64_t total_size, > goto out; > } > =20 > - bdrv_close(bs); > + bdrv_unref(bs); > + bs =3D NULL; > =20 > /* > * And now open the image and make it consistent first (i.e. incre= ase the > @@ -1550,7 +1551,7 @@ static int qcow2_create2(const char *filename, in= t64_t total_size, > */ > BlockDriver* drv =3D bdrv_find_format("qcow2"); > assert(drv !=3D NULL); > - ret =3D bdrv_open(bs, filename, NULL, > + ret =3D bdrv_open(&bs, filename, NULL, > BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv, &local_e= rr); > if (ret < 0) { > error_propagate(errp, local_err); > @@ -1597,10 +1598,11 @@ static int qcow2_create2(const char *filename, = int64_t total_size, > } > } > =20 > - bdrv_close(bs); > + bdrv_unref(bs); > + bs =3D NULL; > =20 > /* Reopen the image without BDRV_O_NO_FLUSH to flush it before ret= urning */ > - ret =3D bdrv_open(bs, filename, NULL, > + ret =3D bdrv_open(&bs, filename, NULL, > BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_BACKING, > drv, &local_err); > if (error_is_set(&local_err)) { > @@ -1610,7 +1612,9 @@ static int qcow2_create2(const char *filename, in= t64_t total_size, > =20 > ret =3D 0; > out: > - bdrv_unref(bs); > + if (bs) { > + bdrv_unref(bs); > + } > return ret; > } > =20 > diff --git a/block/vmdk.c b/block/vmdk.c > index 99ca60f..0fbf230 100644 > --- a/block/vmdk.c > +++ b/block/vmdk.c > @@ -1755,10 +1755,9 @@ static int vmdk_create(const char *filename, QEM= UOptionParameter *options, > goto exit; > } > if (backing_file) { > - BlockDriverState *bs =3D bdrv_new(""); > - ret =3D bdrv_open(bs, backing_file, NULL, BDRV_O_NO_BACKING, N= ULL, errp); > + BlockDriverState *bs =3D NULL; > + ret =3D bdrv_open(&bs, backing_file, NULL, BDRV_O_NO_BACKING, = NULL, errp); > if (ret !=3D 0) { > - bdrv_unref(bs); > goto exit; > } > if (strcmp(bs->drv->format_name, "vmdk")) { > diff --git a/block/vvfat.c b/block/vvfat.c > index 664941c..ae7bc6f 100644 > --- a/block/vvfat.c > +++ b/block/vvfat.c > @@ -2936,15 +2936,13 @@ static int enable_write_target(BDRVVVFATState *= s) > goto err; > } > =20 > - s->qcow =3D bdrv_new(""); > - > - ret =3D bdrv_open(s->qcow, s->qcow_filename, NULL, > + s->qcow =3D NULL; > + ret =3D bdrv_open(&s->qcow, s->qcow_filename, NULL, > BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, bdrv_qcow= , > &local_err); > if (ret < 0) { > qerror_report_err(local_err); > error_free(local_err); > - bdrv_unref(s->qcow); > goto err; > } > =20 > diff --git a/blockdev.c b/blockdev.c > index 36ceece..42163f8 100644 > --- a/blockdev.c > +++ b/blockdev.c > @@ -510,7 +510,7 @@ static DriveInfo *blockdev_init(const char *file, Q= Dict *bs_opts, > bdrv_flags |=3D ro ? 0 : BDRV_O_RDWR; > =20 > QINCREF(bs_opts); > - ret =3D bdrv_open(dinfo->bdrv, file, bs_opts, bdrv_flags, drv, &er= ror); > + ret =3D bdrv_open(&dinfo->bdrv, file, bs_opts, bdrv_flags, drv, &e= rror); > =20 > if (ret < 0) { > error_setg(errp, "could not open disk image %s: %s", > @@ -1301,12 +1301,11 @@ static void external_snapshot_prepare(BlkTransa= ctionState *common, > qstring_from_str(snapshot_node_name)); > } > =20 > - /* We will manually add the backing_hd field to the bs later */ > - state->new_bs =3D bdrv_new(""); > /* TODO Inherit bs->options or only take explicit options with an > * extended QMP command? */ The state has been g_malloc0 so ok. > - ret =3D bdrv_open(state->new_bs, new_image_file, options, > + ret =3D bdrv_open(&state->new_bs, new_image_file, options, > flags | BDRV_O_NO_BACKING, drv, &local_err); > + /* We will manually add the backing_hd field to the bs later */ > if (ret !=3D 0) { > error_propagate(errp, local_err); > } > @@ -1555,7 +1554,7 @@ static void qmp_bdrv_open_encrypted(BlockDriverSt= ate *bs, const char *filename, > Error *local_err =3D NULL; > int ret; > =20 > - ret =3D bdrv_open(bs, filename, NULL, bdrv_flags, drv, &local_err)= ; It already open here so ok. > + ret =3D bdrv_open(&bs, filename, NULL, bdrv_flags, drv, &local_err= ); > if (ret < 0) { > error_propagate(errp, local_err); > return; > @@ -1906,7 +1905,7 @@ void qmp_drive_backup(const char *device, const c= har *target, > Error **errp) > { > BlockDriverState *bs; > - BlockDriverState *target_bs; > + BlockDriverState *target_bs =3D NULL; > BlockDriverState *source =3D NULL; > BlockDriver *drv =3D NULL; > Error *local_err =3D NULL; > @@ -1991,10 +1990,8 @@ void qmp_drive_backup(const char *device, const = char *target, > return; > } > =20 > - target_bs =3D bdrv_new(""); > - ret =3D bdrv_open(target_bs, target, NULL, flags, drv, &local_err)= ; > + ret =3D bdrv_open(&target_bs, target, NULL, flags, drv, &local_err= ); > if (ret < 0) { > - bdrv_unref(target_bs); > error_propagate(errp, local_err); > return; > } > @@ -2027,7 +2024,7 @@ void qmp_drive_mirror(const char *device, const c= har *target, > Error **errp) > { > BlockDriverState *bs; > - BlockDriverState *source, *target_bs; > + BlockDriverState *source, *target_bs =3D NULL; > BlockDriver *drv =3D NULL; > Error *local_err =3D NULL; > int flags; > @@ -2135,11 +2132,9 @@ void qmp_drive_mirror(const char *device, const = char *target, > /* Mirroring takes care of copy-on-write using the source's backin= g > * file. > */ > - target_bs =3D bdrv_new(""); > - ret =3D bdrv_open(target_bs, target, NULL, flags | BDRV_O_NO_BACKI= NG, drv, > + ret =3D bdrv_open(&target_bs, target, NULL, flags | BDRV_O_NO_BACK= ING, drv, > &local_err); > if (ret < 0) { > - bdrv_unref(target_bs); > error_propagate(errp, local_err); > return; > } > diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c > index 098f6c6..14e6d0b 100644 > --- a/hw/block/xen_disk.c > +++ b/hw/block/xen_disk.c > @@ -813,7 +813,7 @@ static int blk_connect(struct XenDevice *xendev) > Error *local_err =3D NULL; > BlockDriver *drv =3D bdrv_find_whitelisted_format(blkdev->= fileproto, > readonly); > - if (bdrv_open(blkdev->bs, > + if (bdrv_open(&blkdev->bs, > blkdev->filename, NULL, qflags, drv, &local_= err) !=3D 0) > { > xen_be_printf(&blkdev->xendev, 0, "error: %s\n", > diff --git a/include/block/block.h b/include/block/block.h > index 963a61f..980869d 100644 > --- a/include/block/block.h > +++ b/include/block/block.h > @@ -190,7 +190,7 @@ int bdrv_open_image(BlockDriverState **pbs, const c= har *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 *bs, const char *filename, QDict *optio= ns, > +int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *opt= ions, > int flags, BlockDriver *drv, Error **errp); > BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, > BlockDriverState *bs, int flags); > diff --git a/qemu-img.c b/qemu-img.c > index c989850..c39d486 100644 > --- a/qemu-img.c > +++ b/qemu-img.c > @@ -289,7 +289,7 @@ static BlockDriverState *bdrv_new_open(const char *= filename, > drv =3D NULL; > } > =20 > - ret =3D bdrv_open(bs, filename, NULL, flags, drv, &local_err); > + ret =3D bdrv_open(&bs, filename, NULL, flags, drv, &local_err); I wonder if the if(bs) test in the fail label is dead code. The bdrv_unref in the test branch is not. I don't see how bs could be NULL. > if (ret < 0) { > error_report("Could not open '%s': %s", filename, > error_get_pretty(local_err)); > @@ -2314,7 +2314,7 @@ static int img_rebase(int argc, char **argv) > =20 > bs_old_backing =3D bdrv_new("old_backing"); > bdrv_get_backing_filename(bs, backing_name, sizeof(backing_nam= e)); > - ret =3D bdrv_open(bs_old_backing, backing_name, NULL, BDRV_O_F= LAGS, > + ret =3D bdrv_open(&bs_old_backing, backing_name, NULL, BDRV_O_= FLAGS, > old_backing_drv, &local_err); > if (ret) { > error_report("Could not open old backing file '%s': %s", > @@ -2324,7 +2324,7 @@ static int img_rebase(int argc, char **argv) > } > if (out_baseimg[0]) { > bs_new_backing =3D bdrv_new("new_backing"); > - ret =3D bdrv_open(bs_new_backing, out_baseimg, NULL, BDRV_= O_FLAGS, > + ret =3D bdrv_open(&bs_new_backing, out_baseimg, NULL, BDRV= _O_FLAGS, > new_backing_drv, &local_err); > if (ret) { > error_report("Could not open new backing file '%s': %s= ", > diff --git a/qemu-io.c b/qemu-io.c > index d669028..2f06dc6 100644 > --- a/qemu-io.c > +++ b/qemu-io.c > @@ -68,7 +68,7 @@ static int openfile(char *name, int flags, int growab= le, QDict *opts) > } else { > qemuio_bs =3D bdrv_new("hda"); > =20 > - if (bdrv_open(qemuio_bs, name, opts, flags, NULL, &local_err) = < 0) { > + if (bdrv_open(&qemuio_bs, name, 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 136e8c9..0cf123c 100644 > --- a/qemu-nbd.c > +++ b/qemu-nbd.c > @@ -597,7 +597,7 @@ int main(int argc, char **argv) > =20 > bs =3D bdrv_new("hda"); > srcpath =3D argv[optind]; > - ret =3D bdrv_open(bs, srcpath, NULL, flags, drv, &local_err); > + ret =3D bdrv_open(&bs, srcpath, NULL, flags, drv, &local_err); > if (ret < 0) { > errno =3D -ret; > err(EXIT_FAILURE, "Failed to bdrv_open '%s': %s", argv[optind]= , > --=20 > 1.8.5.3 >=20 >=20