fuse: Allow exporting BDSs via FUSE

block-export-add type=fuse allows mounting block graph nodes via FUSE on
some existing regular file. That file should then appears like a raw
disk image, and acc

fuse: Allow exporting BDSs via FUSE

block-export-add type=fuse allows mounting block graph nodes via FUSE on
some existing regular file. That file should then appears like a raw
disk image, and accesses to it result in accesses to the exported BDS.

Right now, we only implement the necessary block export functions to set
it up and shut it down. We do not implement any access functions, so
accessing the mount point only results in errors. This will be
addressed by a followup patch.

We keep a hash table of exported mount points, because we want to be
able to detect when users try to use a mount point twice. This is
because we invoke stat() to check whether the given mount point is a
regular file, but if that file is served by ourselves (because it is
already used as a mount point), then this stat() would have to be served
by ourselves, too, which is impossible to do while we (as the caller)
are waiting for it to settle. Therefore, keep track of mount point
paths to at least catch the most obvious instances of that problem.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20201027190600.192171-3-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc,pci,vhost,virtio: fixes

Lots of fixes all over the place.
virtio-mem and virtio-iommu patches are kind of fixes but
it s

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc,pci,vhost,virtio: fixes

Lots of fixes all over the place.
virtio-mem and virtio-iommu patches are kind of fixes but
it seems better to just make them behave sanely than
try to educate users about the limitations ...

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Wed 04 Nov 2020 18:40:03 GMT
# gpg: using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg: issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (31 commits)
contrib/vhost-user-blk: fix get_config() information leak
block/export: fix vhost-user-blk get_config() information leak
block/export: make vhost-user-blk config space little-endian
configure: introduce --enable-vhost-user-blk-server
libvhost-user: follow QEMU comment style
vhost-blk: set features before setting inflight feature
Revert "vhost-blk: set features before setting inflight feature"
net: Add vhost-vdpa in show_netdevs()
vhost-vdpa: Add qemu_close in vhost_vdpa_cleanup
vfio: Don't issue full 2^64 unmap
virtio-iommu: Set supported page size mask
vfio: Set IOMMU page size as per host supported page size
memory: Add interface to set iommu page size mask
virtio-iommu: Add notify_flag_changed() memory region callback
virtio-iommu: Add replay() memory region callback
virtio-iommu: Call memory notifiers in attach/detach
virtio-iommu: Add memory notifiers for map/unmap
virtio-iommu: Store memory region in endpoint struct
virtio-iommu: Fix virtio_iommu_mr()
hw/smbios: Fix leaked fd in save_opt_one() error path
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

configure: introduce --enable-vhost-user-blk-server

Make it possible to compile out the vhost-user-blk server. It is enabled
by default on Linux.

Note that vhost-user-server.c depends on libvhost-u

configure: introduce --enable-vhost-user-blk-server

Make it possible to compile out the vhost-user-blk server. It is enabled
by default on Linux.

Note that vhost-user-server.c depends on libvhost-user, which requires
CONFIG_LINUX. The CONFIG_VHOST_USER dependency was erroneous since that
option controls vhost-user frontends (previously known as "master") and
not device backends (previously known as "slave").

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20201027173528.213464-3-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/stefanha-gitlab/tags/block-pull-request' into staging

Pull request

v3:
* Fix linker error on FreeBSD and other !CONFIG_LINUX host OSes [Peter]

# gpg: Signatu

Merge remote-tracking branch 'remotes/stefanha-gitlab/tags/block-pull-request' into staging

Pull request

v3:
* Fix linker error on FreeBSD and other !CONFIG_LINUX host OSes [Peter]

# gpg: Signature made Fri 23 Oct 2020 16:21:19 BST
# gpg: using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha-gitlab/tags/block-pull-request: (28 commits)
iotests: add commit top->base cases to 274
block/io: fix bdrv_is_allocated_above
block/io: bdrv_common_block_status_above: support bs == base
block/io: bdrv_common_block_status_above: support include_base
block/io: fix bdrv_co_block_status_above
block/export: add vhost-user-blk multi-queue support
block/export: add iothread and fixed-iothread options
block: move block exports to libblockdev
qemu-storage-daemon: avoid compiling blockdev_ss twice
util/vhost-user-server: use static library in meson.build
util/vhost-user-server: move header to include/
block/export: convert vhost-user-blk server to block export API
block/export: report flush errors
util/vhost-user-server: rework vu_client_trip() coroutine lifecycle
util/vhost-user-server: check EOF when reading payload
util/vhost-user-server: fix memory leak in vu_message_read()
util/vhost-user-server: drop unused DevicePanicNotifier
block/export: consolidate request structs into VuBlockReq
util/vhost-user-server: drop unnecessary watch deletion
util/vhost-user-server: drop unnecessary QOM cast
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

block/export: add iothread and fixed-iothread options

Make it possible to specify the iothread where the export will run. By
default the block node can be moved to other AioContexts later and the
ex

block/export: add iothread and fixed-iothread options

Make it possible to specify the iothread where the export will run. By
default the block node can be moved to other AioContexts later and the
export will follow. The fixed-iothread option forces strict behavior
that prevents changing AioContext while the export is active. See the
QAPI docs for details.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200929125516.186715-5-stefanha@redhat.com
[Fix stray '#' character in block-export.json and add missing "(since:
5.2)" as suggested by Eric Blake.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

util/vhost-user-server: use static library in meson.build

Don't compile contrib/libvhost-user/libvhost-user.c again. Instead build
the static library once and then reuse it throughout QEMU.

Also sw

util/vhost-user-server: use static library in meson.build

Don't compile contrib/libvhost-user/libvhost-user.c again. Instead build
the static library once and then reuse it throughout QEMU.

Also switch from CONFIG_LINUX to CONFIG_VHOST_USER, which is what the
vhost-user tools (vhost-user-gpu, etc) do.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-14-stefanha@redhat.com
[Added CONFIG_LINUX again because libvhost-user doesn't build on macOS.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

block/export: convert vhost-user-blk server to block export API

Use the new QAPI block exports API instead of defining our own QOM
objects.

This is a large change because the lifecycle of VuBlockDe

block/export: convert vhost-user-blk server to block export API

Use the new QAPI block exports API instead of defining our own QOM
objects.

This is a large change because the lifecycle of VuBlockDev needs to
follow BlockExportDriver. QOM properties are replaced by QAPI options
objects.

VuBlockDev is renamed VuBlkExport and contains a BlockExport field.
Several fields can be dropped since BlockExport already has equivalents.

The file names and meson build integration will be adjusted in a future
patch. libvhost-user should probably be built as a static library that
is linked into QEMU instead of as a .c file that results in duplicate
compilation.

The new command-line syntax is:

$ qemu-storage-daemon \
--blockdev file,node-name=drive0,filename=test.img \
--export vhost-user-blk,node-name=drive0,id=export0,unix-socket=/tmp/vhost-user-blk.sock

Note that unix-socket is optional because we may wish to accept chardevs
too in the future.

Markus noted that supported address families are not explicit in the
QAPI schema. It is unlikely that support for more address families will
be added since file descriptor passing is required and few address
families support it. If a new address family needs to be added, then the
QAPI 'features' syntax can be used to advertize them.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20200924151549.913737-12-stefanha@redhat.com
[Skip test on big-endian host architectures because this device doesn't
support them yet (as already mentioned in a code comment).
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches:

- Add block export infrastructure
- iotests improvements
- Document the throttle block filter
- Misc

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches:

- Add block export infrastructure
- iotests improvements
- Document the throttle block filter
- Misc code cleanups

# gpg: Signature made Fri 02 Oct 2020 15:36:53 BST
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream: (37 commits)
qcow2: Use L1E_SIZE in qcow2_write_l1_entry()
qemu-storage-daemon: Fix help line for --export
iotests: Test block-export-* QMP interface
iotests: Allow supported and unsupported formats at the same time
iotests: Introduce qemu_nbd_list_log()
iotests: Factor out qemu_tool_pipe_and_status()
nbd: Deprecate nbd-server-add/remove
nbd: Merge nbd_export_new() and nbd_export_create()
block/export: Move writable to BlockExportOptions
block/export: Add query-block-exports
block/export: Create BlockBackend in blk_exp_add()
block/export: Move blk to BlockExport
block/export: Add BLOCK_EXPORT_DELETED event
block/export: Add block-export-del
block/export: Move strong user reference to block_exports
block/export: Add 'id' option to block-export-add
block/export: Add blk_exp_close_all(_type)
block/export: Allocate BlockExport in blk_exp_add()
block/export: Add node-name to BlockExportOptions
block/export: Move AioContext from NBDExport to BlockExport
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

block/export: Move writable to BlockExportOptions

The 'writable' option is a basic option that will probably be applicable
to most if not all export types that we will implement. Move it from NBD
to

block/export: Move writable to BlockExportOptions

The 'writable' option is a basic option that will probably be applicable
to most if not all export types that we will implement. Move it from NBD
to the generic BlockExport layer.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-26-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Add query-block-exports

This adds a simple QMP command to query the list of block exports.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Mess

block/export: Add query-block-exports

This adds a simple QMP command to query the list of block exports.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-25-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Create BlockBackend in blk_exp_add()

Every export type will need a BlockBackend, so creating it centrally in
blk_exp_add() instead of the .create driver callback avoids duplication.

S

block/export: Create BlockBackend in blk_exp_add()

Every export type will need a BlockBackend, so creating it centrally in
blk_exp_add() instead of the .create driver callback avoids duplication.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-24-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Move blk to BlockExport

Every block export has a BlockBackend representing the disk that is
exported. It should live in BlockExport therefore.

Signed-off-by: Kevin Wolf <kwolf@redhat.

block/export: Move blk to BlockExport

Every block export has a BlockBackend representing the disk that is
exported. It should live in BlockExport therefore.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-23-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Add BLOCK_EXPORT_DELETED event

Clients may want to know when an export has finally disappeard
(block-export-del returns earlier than that in the general case), so add
a QAPI event for

block/export: Add BLOCK_EXPORT_DELETED event

Clients may want to know when an export has finally disappeard
(block-export-del returns earlier than that in the general case), so add
a QAPI event for it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200924152717.287415-22-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Add block-export-del

Implement a new QMP command block-export-del and make nbd-server-remove
a wrapper around it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <

block/export: Add block-export-del

Implement a new QMP command block-export-del and make nbd-server-remove
a wrapper around it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-21-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Move strong user reference to block_exports

The reference owned by the user/monitor that is created when adding the
export and dropped when removing it was tied to the 'exports' list i

block/export: Move strong user reference to block_exports

The reference owned by the user/monitor that is created when adding the
export and dropped when removing it was tied to the 'exports' list in
nbd/server.c. Every block export will have a user reference, so move it
to the block export level and tie it to the 'block_exports' list in
block/export/export.c instead. This is necessary for introducing a QMP
command for removing exports.

Note that exports are present in block_exports even after the user has
requested shutdown. This is different from NBD's exports where exports
are immediately removed on a shutdown request, even if they are still in
the process of shutting down. In order to avoid that the user still
interacts with an export that is shutting down (and possibly removes it
a second time), we need to remember if the user actually still owns it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-20-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Add 'id' option to block-export-add

We'll need an id to identify block exports in monitor commands. This
adds one.

Note that this is different from the 'name' option in the NBD server

block/export: Add 'id' option to block-export-add

We'll need an id to identify block exports in monitor commands. This
adds one.

Note that this is different from the 'name' option in the NBD server,
which is the externally visible export name. While block export ids need
to be unique in the whole process, export names must be unique only for
the same server. Different export types or (potentially in the future)
multiple NBD servers can have the same export name externally, but still
need different block export ids internally.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-19-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Add blk_exp_close_all(_type)

This adds a function to shut down all block exports, and another one to
shut down the block exports of a single type. The latter is used for now
when stopp

block/export: Add blk_exp_close_all(_type)

This adds a function to shut down all block exports, and another one to
shut down the block exports of a single type. The latter is used for now
when stopping the NBD server. As soon as we implement support for
multiple NBD servers, we'll need a per-server list of exports and it
will be replaced by a function using that.

As a side effect, the BlockExport layer has a list tracking all existing
exports now. closed_exports loses its only user and can go away.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-18-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Allocate BlockExport in blk_exp_add()

Instead of letting the driver allocate and return the BlockExport
object, allocate it already in blk_exp_add() and pass it. This allows us
to init

block/export: Allocate BlockExport in blk_exp_add()

Instead of letting the driver allocate and return the BlockExport
object, allocate it already in blk_exp_add() and pass it. This allows us
to initialise the generic part before calling into the driver so that
the driver can just use these values instead of having to parse the
options a second time.

For symmetry, move freeing the BlockExport to blk_exp_unref().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-17-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Move AioContext from NBDExport to BlockExport

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-15-kwolf@redhat

block/export: Move AioContext from NBDExport to BlockExport

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-15-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Move refcount from NBDExport to BlockExport

Having a refcount makes sense for all types of block exports. It is also
a prerequisite for keeping a list of all exports at the BlockExport

block/export: Move refcount from NBDExport to BlockExport

Having a refcount makes sense for all types of block exports. It is also
a prerequisite for keeping a list of all exports at the BlockExport
level.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-14-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Remove magic from block-export-add

nbd-server-add tries to be convenient and adds two questionable
features that we don't want to share in block-export-add, even for NBD
exports:

1. W

block/export: Remove magic from block-export-add

nbd-server-add tries to be convenient and adds two questionable
features that we don't want to share in block-export-add, even for NBD
exports:

1. When requesting a writable export of a read-only device, the export
is silently downgraded to read-only. This should be an error in the
context of block-export-add.

2. When using a BlockBackend name, unplugging the device from the guest
will automatically stop the NBD server, too. This may sometimes be
what you want, but it could also be very surprising. Let's keep
things explicit with block-export-add. If the user wants to stop the
export, they should tell us so.

Move these things into the nbd-server-add QMP command handler so that
they apply only there.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-8-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/export: Add BlockExport infrastructure and block-export-add

We want to have a common set of commands for all types of block exports.
Currently, this is only NBD, but we're going to add more ty

block/export: Add BlockExport infrastructure and block-export-add

We want to have a common set of commands for all types of block exports.
Currently, this is only NBD, but we're going to add more types.

This patch adds the basic BlockExport and BlockExportDriver structs and
a QMP command block-export-add that creates a new export based on the
given BlockExportOptions.

qmp_nbd_server_add() becomes a wrapper around qmp_block_export_add().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200924152717.287415-5-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...