summaryrefslogtreecommitdiffstats
path: root/block/export
Commit message (Collapse)AuthorAgeFilesLines
* block/export: disable VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD for nowStefan Hajnoczi2021-03-191-2/+1Star
| | | | | | | | | | | | | | | | The vhost-user in-flight shmfd feature has not been tested with qemu-storage-daemon's vhost-user-blk server. Disable this optional feature for now because it requires MFD_ALLOW_SEALING, which is not available in some CI environments. If we need this feature in the future it can be re-enabled after testing. Reported-by: Peter Maydell <peter.maydell@linaro.org> Cc: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20210309094106.196911-2-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/export: port virtio-blk read/write range checkStefan Hajnoczi2021-03-081-3/+16
| | | | | | | | Check that the sector number and byte count are valid. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20210223144653.811468-13-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/export: port virtio-blk discard/write zeroes input validationStefan Hajnoczi2021-03-081-23/+93
| | | | | | | | | | Validate discard/write zeroes the same way we do for virtio-blk. Some of these checks are mandated by the VIRTIO specification, others are internal to QEMU. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20210223144653.811468-11-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/export: fix vhost-user-blk export sector number calculationStefan Hajnoczi2021-03-081-1/+1
| | | | | | | | | | | | | | | | | | The driver is supposed to honor the blk_size field but the protocol still uses 512-byte sector numbers. It is incorrect to multiply req->sector_num by blk_size. VIRTIO 1.1 5.2.5 Device Initialization says: blk_size can be read to determine the optimal sector size for the driver to use. This does not affect the units used in the protocol (always 512 bytes), but awareness of the correct value can affect performance. Fixes: 3578389bcf76c824a5d82e6586a6f0c71e56f2aa ("block/export: vhost-user block device backend server") Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20210223144653.811468-10-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/export: use VIRTIO_BLK_SECTOR_BITSStefan Hajnoczi2021-03-081-3/+12
| | | | | | | | | | | | | | | | Use VIRTIO_BLK_SECTOR_BITS and VIRTIO_BLK_SECTOR_SIZE when dealing with virtio-blk sector numbers. Although the values happen to be the same as BDRV_SECTOR_BITS and BDRV_SECTOR_SIZE, they are conceptually different. This makes it clearer when we are dealing with virtio-blk sector units. Use VIRTIO_BLK_SECTOR_BITS in vu_blk_initialize_config(). Later patches will use it the new constants the virtqueue request processing code path. Suggested-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20210223144653.811468-9-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/export: fix blk_size double byteswapStefan Hajnoczi2021-03-081-1/+1
| | | | | | | | | | The config->blk_size field is little-endian. Use the native-endian blk_size variable to avoid double byteswapping. Fixes: 11f60f7eaee2630dd6fa0c3a8c49f792e46c4cf1 ("block/export: make vhost-user-blk config space little-endian") Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20210223144653.811468-8-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qapi: Use QAPI_LIST_APPEND in trivial casesEric Blake2021-01-281-5/+2Star
| | | | | | | | | | | | The easiest spots to use QAPI_LIST_APPEND are where we already have an obvious pointer to the tail of a list. While at it, consistently use the variable name 'tail' for that purpose. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20210113221013.390592-5-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
* fuse: Implement hole detection through lseekMax Reitz2020-12-111-0/+77
| | | | | | | | | | This is a relatively new feature in libfuse (available since 3.8.0, which was released in November 2019), so we have to add a dedicated check whether it is available before making use of it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20201027190600.192171-7-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* fuse: (Partially) implement fallocate()Max Reitz2020-12-111-0/+84
| | | | | | | | | This allows allocating areas after the (old) EOF as part of a growing resize, writing zeroes, and discarding. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20201027190600.192171-6-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* fuse: Allow growable exportsMax Reitz2020-12-111-8/+36
| | | | | | | | | | | | | | These will behave more like normal files in that writes beyond the EOF will automatically grow the export size. As an optimization, keep the RESIZE permission for growable exports so we do not have to take it for every post-EOF write. (This permission is not released when the export is destroyed, because at that point the BlockBackend is destroyed altogether anyway.) Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20201027190600.192171-5-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* fuse: Implement standard FUSE operationsMax Reitz2020-12-111-0/+242
| | | | | | | | | This makes the export actually useful instead of only producing errors whenever it is accessed. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20201027190600.192171-4-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* fuse: Allow exporting BDSs via FUSEMax Reitz2020-12-113-0/+301
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* block/export: avoid g_return_val_if() input validationStefan Hajnoczi2020-12-091-1/+3
| | | | | | | | | | | | | | Do not validate input with g_return_val_if(). This API is intended for checking programming errors and is compiled out with -DG_DISABLE_CHECKS. Use an explicit if statement for input validation so it cannot accidentally be compiled out. Suggested-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20201118091644.199527-5-stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* libvhost-user: make it a meson subprojectMarc-André Lureau2020-12-081-1/+1
| | | | | | | | | | | | | By making libvhost-user a subproject, check it builds standalone (without the global QEMU cflags etc). Note that the library still relies on QEMU include/qemu/atomic.h and linux_headers/. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20201125100640.366523-6-marcandre.lureau@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* meson: move vhost_user_blk_server to meson.buildStefan Hajnoczi2020-11-121-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | The --enable/disable-vhost-user-blk-server options were implemented in ./configure. There has been confusion about them and part of the problem is that the shell syntax used for setting the default value is not easy to read. Move the option over to meson where the conditions are easier to understand: have_vhost_user_blk_server = (targetos == 'linux') if get_option('vhost_user_blk_server').enabled() if targetos != 'linux' error('vhost_user_blk_server requires linux') endif elif get_option('vhost_user_blk_server').disabled() or not have_system have_vhost_user_blk_server = false endif This patch does not change behavior. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20201110171121.1265142-2-stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
* block/export: fix vhost-user-blk get_config() information leakStefan Hajnoczi2020-11-031-0/+3
| | | | | | | | | Refuse get_config() requests in excess of sizeof(struct virtio_blk_config). Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20201027173528.213464-5-stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* block/export: make vhost-user-blk config space little-endianStefan Hajnoczi2020-11-031-13/+12Star
| | | | | | | | | | | | VIRTIO 1.0 devices have little-endian configuration space. The vhost-user-blk-server.c code already uses little-endian for virtqueue processing but not for the configuration space fields. Fix this so the vhost-user-blk export works on big-endian hosts. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20201027173528.213464-4-stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* configure: introduce --enable-vhost-user-blk-serverStefan Hajnoczi2020-11-032-3/+3
| | | | | | | | | | | | | | | 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>
* block/export: add vhost-user-blk multi-queue supportStefan Hajnoczi2020-10-231-6/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow the number of queues to be configured using --export vhost-user-blk,num-queues=N. This setting should match the QEMU --device vhost-user-blk-pci,num-queues=N setting but QEMU vhost-user-blk.c lowers its own value if the vhost-user-blk backend offers fewer queues than QEMU. The vhost-user-blk-server.c code is already capable of multi-queue. All virtqueue processing runs in the same AioContext. No new locking is needed. Add the num-queues=N option and set the VIRTIO_BLK_F_MQ feature bit. Note that the feature bit only announces the presence of the num_queues configuration space field. It does not promise that there is more than 1 virtqueue, so we can set it unconditionally. I tested multi-queue by running a random read fio test with numjobs=4 on an -smp 4 guest. After the benchmark finished the guest /proc/interrupts file showed activity on all 4 virtio-blk MSI-X. The /sys/block/vda/mq/ directory shows that Linux blk-mq has 4 queues configured. An automated test is included in the next commit. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Markus Armbruster <armbru@redhat.com> Message-id: 20201001144604.559733-2-stefanha@redhat.com [Fixed accidental tab characters as suggested by Markus Armbruster --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/export: add iothread and fixed-iothread optionsStefan Hajnoczi2020-10-232-2/+34
| | | | | | | | | | | | | | | 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>
* block: move block exports to libblockdevStefan Hajnoczi2020-10-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | Block exports are used by softmmu, qemu-storage-daemon, and qemu-nbd. They are not used by other programs and are not otherwise needed in libblock. Undo the recent move of blockdev-nbd.c from blockdev_ss into block_ss. Since bdrv_close_all() (libblock) calls blk_exp_close_all() (libblockdev) a stub function is required.. Make qemu-nbd.c use signal handling utility functions instead of duplicating the code. This helps because os-posix.c is in libblockdev and it depends on a qemu_system_killed() symbol that qemu-nbd.c lacks. Once we use the signal handling utility functions we also end up providing the necessary symbol. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20200929125516.186715-4-stefanha@redhat.com [Fixed s/ndb/nbd/ typo in commit description as suggested by Eric Blake --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* util/vhost-user-server: use static library in meson.buildStefan Hajnoczi2020-10-232-5/+5
| | | | | | | | | | | | | | 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>
* util/vhost-user-server: move header to include/Stefan Hajnoczi2020-10-231-1/+1
| | | | | | | | | Headers used by other subsystems are located in include/. Also add the vhost-user-server and vhost-user-blk-server headers to MAINTAINERS. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-13-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/export: convert vhost-user-blk server to block export APIStefan Hajnoczi2020-10-234-352/+126Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* block/export: report flush errorsStefan Hajnoczi2020-10-231-4/+7
| | | | | | | | Propagate the flush return value since errors are possible. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-11-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* util/vhost-user-server: rework vu_client_trip() coroutine lifecycleStefan Hajnoczi2020-10-231-7/+2Star
| | | | | | | | | | | | The vu_client_trip() coroutine is leaked during AioContext switching. It is also unsafe to destroy the vu_dev in panic_cb() since its callers still access it in some cases. Rework the lifecycle to solve these safety issues. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-10-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* util/vhost-user-server: drop unused DevicePanicNotifierStefan Hajnoczi2020-10-231-2/+1Star
| | | | | | | | The device panic notifier callback is not used. Drop it. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-7-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/export: consolidate request structs into VuBlockReqStefan Hajnoczi2020-10-231-47/+21Star
| | | | | | | | | | | | Only one struct is needed per request. Drop req_data and the separate VuBlockReq instance. Instead let vu_queue_pop() allocate everything at once. This fixes the req_data memory leak in vu_block_virtio_process_req(). Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200924151549.913737-6-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/export: vhost-user block device backend serverCoiby Xu2020-10-232-0/+697
| | | | | | | | | | | | | | | | | | | | | | | By making use of libvhost-user, block device drive can be shared to the connected vhost-user client. Only one client can connect to the server one time. Since vhost-user-server needs a block drive to be created first, delay the creation of this object. Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Coiby Xu <coiby.xu@gmail.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-id: 20200918080912.321299-6-coiby.xu@gmail.com [Shorten "vhost_user_blk_server" string to "vhost_user_blk" to avoid the following compiler warning: ../block/export/vhost-user-blk-server.c:178:50: error: ‘%s’ directive output truncated writing 21 bytes into a region of size 20 [-Werror=format-truncation=] and fix "Invalid size %ld ..." ssize_t format string arguments for 32-bit hosts. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/export: Move writable to BlockExportOptionsKevin Wolf2020-10-021-1/+15
| | | | | | | | | | | | 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>
* block/export: Add query-block-exportsKevin Wolf2020-10-021-0/+23
| | | | | | | | | | 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>
* block/export: Create BlockBackend in blk_exp_add()Kevin Wolf2020-10-021-4/+45
| | | | | | | | | | | 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>
* block/export: Move blk to BlockExportKevin Wolf2020-10-021-0/+3
| | | | | | | | | | | 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>
* block/export: Add BLOCK_EXPORT_DELETED eventKevin Wolf2020-10-021-0/+2
| | | | | | | | | | | | 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>
* block/export: Add block-export-delKevin Wolf2020-10-021-1/+42
| | | | | | | | | | | 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>
* block/export: Move strong user reference to block_exportsKevin Wolf2020-10-021-0/+6
| | | | | | | | | | | | | | | | | | | | | | 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>
* block/export: Add 'id' option to block-export-addKevin Wolf2020-10-021-0/+26
| | | | | | | | | | | | | | | | | | 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>
* block/export: Add blk_exp_close_all(_type)Kevin Wolf2020-10-021-2/+84
| | | | | | | | | | | | | | | | | 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>
* block/export: Allocate BlockExport in blk_exp_add()Kevin Wolf2020-10-021-1/+17
| | | | | | | | | | | | | | | | 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>
* block/export: Move AioContext from NBDExport to BlockExportKevin Wolf2020-10-021-0/+2
| | | | | | | | 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>
* block/export: Move refcount from NBDExport to BlockExportKevin Wolf2020-10-021-0/+14
| | | | | | | | | | | | 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>
* block/export: Remove magic from block-export-addKevin Wolf2020-10-021-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* block/export: Add BlockExport infrastructure and block-export-addKevin Wolf2020-10-022-0/+49
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>