| Message ID | 66bc85ae1f3a1e7d5691739327542299d583ce1b.1477476553.git.berto@igalia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Am 26.10.2016 um 12:29 hat Alberto Garcia geschrieben: > This patch makes the 'device' parameter of the 'block-stream' command > accept a node name that is not a root node. > > In addition to that, operation blockers will be checked in all > intermediate nodes between the top and the base node. > > Signed-off-by: Alberto Garcia <berto@igalia.com> > --- a/qapi/block-core.json > +++ b/qapi/block-core.json > @@ -1464,6 +1464,10 @@ > # with query-block-jobs. The operation can be stopped before it has completed > # using the block-job-cancel command. > # > +# The node that receives the data is called the top image, can be located in > +# any part of the chain (but always above the base image; see below) and can be > +# specified using its device or node name. > +# > # If a base file is specified then sectors are not copied from that base file and > # its backing chain. When streaming completes the image file will have the base > # file as its backing file. This can be used to stream a subset of the backing > @@ -1475,12 +1479,12 @@ > # @job-id: #optional identifier for the newly-created block job. If > # omitted, the device name will be used. (Since 2.7) > # > -# @device: the device name or node-name of a root node > +# @device: the device or node name of the top image > # > # @base: #optional the common backing file name > # > -# @backing-file: #optional The backing file string to write into the active > -# layer. This filename is not validated. > +# @backing-file: #optional The backing file string to write into the top > +# image. This filename is not validated. > # > # If a pathname string is such that it cannot be > # resolved by QEMU, that means that subsequent QMP or As we discussed in v10, this is not discoverable through introspection. You added patch 18 which introduces a base-node option and can serve as a witness for the changed semantics, which is good. Should this be documented here? Kevin
On Wed 26 Oct 2016 04:58:00 PM CEST, Kevin Wolf <kwolf@redhat.com> wrote: > Am 26.10.2016 um 12:29 hat Alberto Garcia geschrieben: >> This patch makes the 'device' parameter of the 'block-stream' command >> accept a node name that is not a root node. >> >> In addition to that, operation blockers will be checked in all >> intermediate nodes between the top and the base node. >> >> Signed-off-by: Alberto Garcia <berto@igalia.com> > >> --- a/qapi/block-core.json >> +++ b/qapi/block-core.json >> @@ -1464,6 +1464,10 @@ >> # with query-block-jobs. The operation can be stopped before it has completed >> # using the block-job-cancel command. >> # >> +# The node that receives the data is called the top image, can be located in >> +# any part of the chain (but always above the base image; see below) and can be >> +# specified using its device or node name. >> +# >> # If a base file is specified then sectors are not copied from that base file and >> # its backing chain. When streaming completes the image file will have the base >> # file as its backing file. This can be used to stream a subset of the backing >> @@ -1475,12 +1479,12 @@ >> # @job-id: #optional identifier for the newly-created block job. If >> # omitted, the device name will be used. (Since 2.7) >> # >> -# @device: the device name or node-name of a root node >> +# @device: the device or node name of the top image >> # >> # @base: #optional the common backing file name >> # >> -# @backing-file: #optional The backing file string to write into the active >> -# layer. This filename is not validated. >> +# @backing-file: #optional The backing file string to write into the top >> +# image. This filename is not validated. >> # >> # If a pathname string is such that it cannot be >> # resolved by QEMU, that means that subsequent QMP or > > As we discussed in v10, this is not discoverable through > introspection. You added patch 18 which introduces a base-node option > and can serve as a witness for the changed semantics, which is > good. Should this be documented here? In the commit message I don't see why not, but in the JSON file? "This feature was added together with the base-node parameter" ? Berto
Am 26.10.2016 um 19:23 hat Alberto Garcia geschrieben: > On Wed 26 Oct 2016 04:58:00 PM CEST, Kevin Wolf <kwolf@redhat.com> wrote: > > Am 26.10.2016 um 12:29 hat Alberto Garcia geschrieben: > >> This patch makes the 'device' parameter of the 'block-stream' command > >> accept a node name that is not a root node. > >> > >> In addition to that, operation blockers will be checked in all > >> intermediate nodes between the top and the base node. > >> > >> Signed-off-by: Alberto Garcia <berto@igalia.com> > > > >> --- a/qapi/block-core.json > >> +++ b/qapi/block-core.json > >> @@ -1464,6 +1464,10 @@ > >> # with query-block-jobs. The operation can be stopped before it has completed > >> # using the block-job-cancel command. > >> # > >> +# The node that receives the data is called the top image, can be located in > >> +# any part of the chain (but always above the base image; see below) and can be > >> +# specified using its device or node name. > >> +# > >> # If a base file is specified then sectors are not copied from that base file and > >> # its backing chain. When streaming completes the image file will have the base > >> # file as its backing file. This can be used to stream a subset of the backing > >> @@ -1475,12 +1479,12 @@ > >> # @job-id: #optional identifier for the newly-created block job. If > >> # omitted, the device name will be used. (Since 2.7) > >> # > >> -# @device: the device name or node-name of a root node > >> +# @device: the device or node name of the top image > >> # > >> # @base: #optional the common backing file name > >> # > >> -# @backing-file: #optional The backing file string to write into the active > >> -# layer. This filename is not validated. > >> +# @backing-file: #optional The backing file string to write into the top > >> +# image. This filename is not validated. > >> # > >> # If a pathname string is such that it cannot be > >> # resolved by QEMU, that means that subsequent QMP or > > > > As we discussed in v10, this is not discoverable through > > introspection. You added patch 18 which introduces a base-node option > > and can serve as a witness for the changed semantics, which is > > good. Should this be documented here? > > In the commit message I don't see why not, but in the JSON file? > > "This feature was added together with the base-node parameter" ? Eric may have a better suggestion for the wording, but maybe something like this: "Presence of this feature can't directly be tested with introspection; check for the presence of base-node instead as a witness for it." Kevin
On Thu 27 Oct 2016 10:58:04 AM CEST, Kevin Wolf wrote: >> >> +# The node that receives the data is called the top image, can be located in >> >> +# any part of the chain (but always above the base image; see below) and can be >> >> +# specified using its device or node name. >> >> +# >> >> # If a base file is specified then sectors are not copied from that base file and >> >> # its backing chain. When streaming completes the image file will have the base >> >> # file as its backing file. This can be used to stream a subset of the backing >> >> @@ -1475,12 +1479,12 @@ >> >> # @job-id: #optional identifier for the newly-created block job. If >> >> # omitted, the device name will be used. (Since 2.7) >> >> # >> >> -# @device: the device name or node-name of a root node >> >> +# @device: the device or node name of the top image >> >> # >> >> # @base: #optional the common backing file name >> >> # >> >> -# @backing-file: #optional The backing file string to write into the active >> >> -# layer. This filename is not validated. >> >> +# @backing-file: #optional The backing file string to write into the top >> >> +# image. This filename is not validated. >> >> # >> >> # If a pathname string is such that it cannot be >> >> # resolved by QEMU, that means that subsequent QMP or >> > >> > As we discussed in v10, this is not discoverable through >> > introspection. You added patch 18 which introduces a base-node >> > option and can serve as a witness for the changed semantics, which >> > is good. Should this be documented here? >> >> In the commit message I don't see why not, but in the JSON file? >> >> "This feature was added together with the base-node parameter" ? > > Eric may have a better suggestion for the wording, but maybe something > like this: > > "Presence of this feature can't directly be tested with introspection; > check for the presence of base-node instead as a witness for it." Ok, sounds good to me. If there's a next version of the series I will include that text, else feel free to put it when you commit. Berto
On 10/27/2016 03:58 AM, Kevin Wolf wrote: >>>> -# @backing-file: #optional The backing file string to write into the active >>>> -# layer. This filename is not validated. >>>> +# @backing-file: #optional The backing file string to write into the top >>>> +# image. This filename is not validated. >>>> # >>>> # If a pathname string is such that it cannot be >>>> # resolved by QEMU, that means that subsequent QMP or >>> >>> As we discussed in v10, this is not discoverable through >>> introspection. You added patch 18 which introduces a base-node option >>> and can serve as a witness for the changed semantics, which is >>> good. Should this be documented here? >> >> In the commit message I don't see why not, but in the JSON file? >> >> "This feature was added together with the base-node parameter" ? > > Eric may have a better suggestion for the wording, but maybe something > like this: > > "Presence of this feature can't directly be tested with introspection; > check for the presence of base-node instead as a witness for it." The sentence on checking for the feature should go earlier, with this paragraph. Maybe as follows: # The node that receives the data is called the top image, and can be # located in any part of the chain (but always above the base image; # see below) and can be specified using its device or node name. # Earlier qemu versions only allowed 'device' to name the top level # node; presence of the 'base-node' parameter during introspection can # be used as a witness of the enhanced semantics of 'device'.
diff --git a/blockdev.c b/blockdev.c index de5b5f5..b5d4d69 100644 --- a/blockdev.c +++ b/blockdev.c @@ -2937,7 +2937,7 @@ void qmp_block_stream(bool has_job_id, const char *job_id, const char *device, bool has_on_error, BlockdevOnError on_error, Error **errp) { - BlockDriverState *bs; + BlockDriverState *bs, *iter; BlockDriverState *base_bs = NULL; AioContext *aio_context; Error *local_err = NULL; @@ -2947,7 +2947,7 @@ void qmp_block_stream(bool has_job_id, const char *job_id, const char *device, on_error = BLOCKDEV_ON_ERROR_REPORT; } - bs = qmp_get_root_bs(device, errp); + bs = bdrv_lookup_bs(device, device, errp); if (!bs) { return; } @@ -2955,10 +2955,6 @@ void qmp_block_stream(bool has_job_id, const char *job_id, const char *device, aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); - if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_STREAM, errp)) { - goto out; - } - if (has_base) { base_bs = bdrv_find_backing_image(bs, base); if (base_bs == NULL) { @@ -2969,6 +2965,13 @@ void qmp_block_stream(bool has_job_id, const char *job_id, const char *device, base_name = base; } + /* Check for op blockers in the whole chain between bs and base */ + for (iter = bs; iter && iter != base_bs; iter = backing_bs(iter)) { + if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) { + goto out; + } + } + /* if we are streaming the entire chain, the result will have no backing * file, and specifying one is therefore an error */ if (base_bs == NULL && has_backing_file) { diff --git a/qapi/block-core.json b/qapi/block-core.json index 97b1205..5fe55ff 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -1464,6 +1464,10 @@ # with query-block-jobs. The operation can be stopped before it has completed # using the block-job-cancel command. # +# The node that receives the data is called the top image, can be located in +# any part of the chain (but always above the base image; see below) and can be +# specified using its device or node name. +# # If a base file is specified then sectors are not copied from that base file and # its backing chain. When streaming completes the image file will have the base # file as its backing file. This can be used to stream a subset of the backing @@ -1475,12 +1479,12 @@ # @job-id: #optional identifier for the newly-created block job. If # omitted, the device name will be used. (Since 2.7) # -# @device: the device name or node-name of a root node +# @device: the device or node name of the top image # # @base: #optional the common backing file name # -# @backing-file: #optional The backing file string to write into the active -# layer. This filename is not validated. +# @backing-file: #optional The backing file string to write into the top +# image. This filename is not validated. # # If a pathname string is such that it cannot be # resolved by QEMU, that means that subsequent QMP or
This patch makes the 'device' parameter of the 'block-stream' command accept a node name that is not a root node. In addition to that, operation blockers will be checked in all intermediate nodes between the top and the base node. Signed-off-by: Alberto Garcia <berto@igalia.com> --- blockdev.c | 15 +++++++++------ qapi/block-core.json | 10 +++++++--- 2 files changed, 16 insertions(+), 9 deletions(-)