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2019-09-24nbd: Grab aio context lock in more placesEric Blake
When iothreads are in use, the failure to grab the aio context results in an assertion failure when trying to unlock things during blk_unref, when trying to unlock a mutex that was not locked. In short, all calls to nbd_export_put need to done while within the correct aio context. But since nbd_export_put can recursively reach itself via nbd_export_close, and recursively grabbing the context would deadlock, we can't do the context grab directly in those functions, but must do so in their callers. Hoist the use of the correct aio_context from nbd_export_new() to its caller qmp_nbd_server_add(). Then tweak qmp_nbd_server_remove(), nbd_eject_notifier(), and nbd_esport_close_all() to grab the right context, so that all callers during qemu now own the context before nbd_export_put() can call blk_unref(). Remaining uses in qemu-nbd don't matter (since that use case does not support iothreads). Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20190917023917.32226-1-eblake@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com>
2019-09-16block: Remove unused masksNir Soffer
Replace confusing usage: ~BDRV_SECTOR_MASK With more clear: (BDRV_SECTOR_SIZE - 1) Remove BDRV_SECTOR_MASK and the unused BDRV_BLOCK_OFFSET_MASK which was it's last user. Signed-off-by: Nir Soffer <nsoffer@redhat.com> Message-id: 20190827185913.27427-3-nsoffer@redhat.com Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-10job: drop job_drainVladimir Sementsov-Ogievskiy
In job_finish_sync job_enter should be enough for a job to make some progress and draining is a wrong tool for it. So use job_enter directly here and drop job_drain with all related staff not used more. Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Tested-by: John Snow <jsnow@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-05nbd: Prepare for NBD_CMD_FLAG_FAST_ZEROEric Blake
Commit fe0480d6 and friends added BDRV_REQ_NO_FALLBACK as a way to avoid wasting time on a preliminary write-zero request that will later be rewritten by actual data, if it is known that the write-zero request will use a slow fallback; but in doing so, could not optimize for NBD. The NBD specification is now considering an extension that will allow passing on those semantics; this patch updates the new protocol bits and 'qemu-nbd --list' output to recognize the bit, as well as the new errno value possible when using the new flag; while upcoming patches will improve the client to use the feature when present, and the server to advertise support for it. The NBD spec recommends (but not requires) that ENOTSUP be avoided for all but failures of a fast zero (the only time it is mandatory to avoid an ENOTSUP failure is when fast zero is supported but not requested during write zeroes; the questionable use is for ENOTSUP to other actions like a normal write request). However, clients that get an unexpected ENOTSUP will either already be treating it the same as EINVAL, or may appreciate the extra bit of information. We were equally loose for returning EOVERFLOW in more situations than recommended by the spec, so if it turns out to be a problem in practice, a later patch can tighten handling for both error codes. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20190823143726.27062-3-eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> [eblake: tweak commit message, also handle EOPNOTSUPP]
2019-09-05nbd: Improve per-export flag handling in serverEric Blake
When creating a read-only image, we are still advertising support for TRIM and WRITE_ZEROES to the client, even though the client should not be issuing those commands. But seeing this requires looking across multiple functions: All callers to nbd_export_new() passed a single flag based solely on whether the export allows writes. Later, we then pass a constant set of flags to nbd_negotiate_options() (namely, the set of flags which we always support, at least for writable images), which is then further dynamically modified with NBD_FLAG_SEND_DF based on client requests for structured options. Finally, when processing NBD_OPT_EXPORT_NAME or NBD_OPT_EXPORT_GO we bitwise-or the original caller's flag with the runtime set of flags we've built up over several functions. Let's refactor things to instead compute a baseline of flags as soon as possible which gets shared between multiple clients, in nbd_export_new(), and changing the signature for the callers to pass in a simpler bool rather than having to figure out flags. We can then get rid of the 'myflags' parameter to various functions, and instead refer to client for everything we need (we still have to perform a bitwise-OR for NBD_FLAG_SEND_DF during NBD_OPT_EXPORT_NAME and NBD_OPT_EXPORT_GO, but it's easier to see what is being computed). This lets us quit advertising senseless flags for read-only images, as well as making the next patch for exposing FAST_ZERO support easier to write. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20190823143726.27062-2-eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> [eblake: improve commit message, update iotest 223]
2019-09-05nbd: Advertise multi-conn for shared read-only connectionsEric Blake
The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be advertised when the server promises cache consistency between simultaneous clients (basically, rules that determine what FUA and flush from one client are able to guarantee for reads from another client). When we don't permit simultaneous clients (such as qemu-nbd without -e), the bit makes no sense; and for writable images, we probably have a lot more work before we can declare that actions from one client are cache-consistent with actions from another. But for read-only images, where flush isn't changing any data, we might as well advertise multi-conn support. What's more, advertisement of the bit makes it easier for clients to determine if 'qemu-nbd -e' was in use, where a second connection will succeed rather than hang until the first client goes away. This patch affects qemu as server in advertising the bit. We may want to consider patches to qemu as client to attempt parallel connections for higher throughput by spreading the load over those connections when a server advertises multi-conn, but for now sticking to one connection per nbd:// BDS is okay. See also: https://bugzilla.redhat.com/1708300 Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20190815185024.7010-1-eblake@redhat.com> [eblake: tweak blockdev-nbd.c to not request shared when writable, fix iotest 233] Reviewed-by: John Snow <jsnow@redhat.com>
2019-08-27block/io: introduce bdrv_co_p{read, write}v_partVladimir Sementsov-Ogievskiy
Introduce extended variants of bdrv_co_preadv and bdrv_co_pwritev with qiov_offset parameter. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20190604161514.262241-10-vsementsov@virtuozzo.com Message-Id: <20190604161514.262241-10-vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27block: define .*_part io handlers in BlockDriverVladimir Sementsov-Ogievskiy
Add handlers supporting qiov_offset parameter: bdrv_co_preadv_part bdrv_co_pwritev_part bdrv_co_pwritev_compressed_part This is used to reduce need of defining local_qiovs and hd_qiovs in all corners of block layer code. The following patches will increase usage of this new API part by part. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20190604161514.262241-5-vsementsov@virtuozzo.com Message-Id: <20190604161514.262241-5-vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-19block: Add bdrv_has_zero_init_truncate()Max Reitz
No .bdrv_has_zero_init() implementation returns 1 if growing the file would add non-zero areas (at least with PREALLOC_MODE_OFF), so using it in lieu of this new function was always safe. But on the other hand, it is possible that growing an image that is not zero-initialized would still add a zero-initialized area, like when using nonpreallocating truncation on a preallocated image. For callers that care only about truncation, not about creation with potential preallocation, this new function is useful. Alternatively, we could have added a PreallocMode parameter to bdrv_has_zero_init(). But the only user would have been qemu-img convert, which does not have a plain PreallocMode value right now -- it would have to parse the creation option to obtain it. Therefore, the simpler solution is to let bdrv_has_zero_init() inquire the preallocation status and add the new bdrv_has_zero_init_truncate() that presupposes PREALLOC_MODE_OFF. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20190724171239.8764-4-mreitz@redhat.com Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19mirror: Fix bdrv_has_zero_init() useMax Reitz
bdrv_has_zero_init() only has meaning for newly created images or image areas. If the mirror job itself did not create the image, it cannot rely on bdrv_has_zero_init()'s result to carry any meaning. This is the case for drive-mirror with mode=existing and always for blockdev-mirror. Note that we only have to zero-initialize the target with sync=full, because other modes actually do not promise that the target will contain the same data as the source after the job -- sync=top only promises to copy anything allocated in the top layer, and sync=none will only copy new I/O. (Which is how mirror has always handled it.) Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20190724171239.8764-3-mreitz@redhat.com Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-16qapi: implement block-dirty-bitmap-remove transaction actionJohn Snow
It is used to do transactional movement of the bitmap (which is possible in conjunction with merge command). Transactional bitmap movement is needed in scenarios with external snapshot, when we don't want to leave copy of the bitmap in the base image. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20190708220502.12977-3-jsnow@redhat.com [Edited "since" version to 4.2 --js] Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16block/dirty-bitmap: add bdrv_dirty_bitmap_getJohn Snow
Add a public interface for get. While we're at it, rename "bdrv_get_dirty_bitmap_locked" to "bdrv_dirty_bitmap_get_locked". (There are more functions to rename to the bdrv_dirty_bitmap_VERB form, but they will wait until the conclusion of this series.) Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20190709232550.10724-11-jsnow@redhat.com Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16block/dirty-bitmap: add bdrv_dirty_bitmap_merge_internalJohn Snow
I'm surprised it didn't come up sooner, but sometimes we have a +busy bitmap as a source. This is dangerous from the QMP API, but if we are the owner that marked the bitmap busy, it's safe to merge it using it as a read only source. It is not safe in the general case to allow users to read from in-use bitmaps, so create an internal variant that foregoes the safety checking. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20190709232550.10724-10-jsnow@redhat.com Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16block/backup: Add mirror sync mode 'bitmap'John Snow
We don't need or want a new sync mode for simple differences in semantics. Create a new mode simply named "BITMAP" that is designed to make use of the new Bitmap Sync Mode field. Because the only bitmap sync mode is 'on-success', this adds no new functionality to the backup job (yet). The old incremental backup mode is maintained as a syntactic sugar for sync=bitmap, mode=on-success. Add all of the plumbing necessary to support this new instruction. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20190709232550.10724-6-jsnow@redhat.com Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2019-08-15' into ↵Peter Maydell
staging nbd patches for 2019-08-15 - Addition of InetSocketAddress keep-alive - Addition of BDRV_REQ_PREFETCH for more efficient copy-on-read - Initial refactoring in preparation of NBD reconnect # gpg: Signature made Thu 15 Aug 2019 19:28:41 BST # gpg: using RSA key A7A16B4A2527436A # gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full] # gpg: aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full] # gpg: aka "[jpeg image of size 6874]" [full] # Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2 F3AA A7A1 6B4A 2527 436A * remotes/ericb/tags/pull-nbd-2019-08-15: block/nbd: refactor nbd connection parameters block/nbd: add cmdline and qapi parameter reconnect-delay block/nbd: move from quit to state block/nbd: use non-blocking io channel for nbd negotiation block/nbd: split connection_co start out of nbd_client_connect nbd: improve CMD_CACHE: use BDRV_REQ_PREFETCH block/stream: use BDRV_REQ_PREFETCH block: implement BDRV_REQ_PREFETCH qapi: Add InetSocketAddress member keep-alive Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-08-16Include qemu/main-loop.h lessMarkus Armbruster
In my "build everything" tree, changing qemu/main-loop.h triggers a recompile of some 5600 out of 6600 objects (not counting tests and objects that don't depend on qemu/osdep.h). It includes block/aio.h, which in turn includes qemu/event_notifier.h, qemu/notify.h, qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h, qemu/thread.h, qemu/timer.h, and a few more. Include qemu/main-loop.h only where it's needed. Touching it now recompiles only some 1700 objects. For block/aio.h and qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the others, they shrink only slightly. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190812052359.30071-21-armbru@redhat.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16Include generated QAPI headers lessMarkus Armbruster
Some of the generated qapi-types-MODULE.h are included all over the place. Changing a QAPI type can trigger massive recompiling. Top scorers recompile more than 1000 out of some 6600 objects (not counting tests and objects that don't depend on qemu/osdep.h): 6300 qapi/qapi-builtin-types.h 5700 qapi/qapi-types-run-state.h 3900 qapi/qapi-types-common.h 3300 qapi/qapi-types-sockets.h 3000 qapi/qapi-types-misc.h 3000 qapi/qapi-types-crypto.h 3000 qapi/qapi-types-job.h 3000 qapi/qapi-types-block-core.h 2800 qapi/qapi-types-block.h 1300 qapi/qapi-types-net.h Clean up headers to include generated QAPI headers only where needed. Impact is negligible except for hw/qdev-properties.h. This header includes qapi/qapi-types-block.h and qapi/qapi-types-misc.h. They are used only in expansions of property definition macros such as DEFINE_PROP_BLOCKDEV_ON_ERROR() and DEFINE_PROP_OFF_AUTO(). Moving their inclusion from hw/qdev-properties.h to the users of these macros avoids pointless recompiles. This is how other property definition macros, such as DEFINE_PROP_NETDEV(), already work. Improves things for some of the top scorers: 3600 qapi/qapi-types-common.h 2800 qapi/qapi-types-sockets.h 900 qapi/qapi-types-misc.h 2200 qapi/qapi-types-crypto.h 2100 qapi/qapi-types-job.h 2100 qapi/qapi-types-block-core.h 270 qapi/qapi-types-block.h Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20190812052359.30071-3-armbru@redhat.com>
2019-08-16include: Make headers more self-containedMarkus Armbruster
Back in 2016, we discussed[1] rules for headers, and these were generally liked: 1. Have a carefully curated header that's included everywhere first. We got that already thanks to Peter: osdep.h. 2. Headers should normally include everything they need beyond osdep.h. If exceptions are needed for some reason, they must be documented in the header. If all that's needed from a header is typedefs, put those into qemu/typedefs.h instead of including the header. 3. Cyclic inclusion is forbidden. This patch gets include/ closer to obeying 2. It's actually extracted from my "[RFC] Baby steps towards saner headers" series[2], which demonstrates a possible path towards checking 2 automatically. It passes the RFC test there. [1] Message-ID: <87h9g8j57d.fsf@blackfin.pond.sub.org> https://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg03345.html [2] Message-Id: <20190711122827.18970-1-armbru@redhat.com> https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg02715.html Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20190812052359.30071-2-armbru@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-15block/nbd: use non-blocking io channel for nbd negotiationVladimir Sementsov-Ogievskiy
No reason to use blocking channel for negotiation and we'll benefit in further reconnect feature, as qio_channel reads and writes will do qemu_coroutine_yield while waiting for io completion. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20190618114328.55249-3-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2019-08-15block: implement BDRV_REQ_PREFETCHVladimir Sementsov-Ogievskiy
Do effective copy-on-read request when we don't need data actually. It will be used for block-stream and NBD_CMD_CACHE. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20190725100550.33801-2-vsementsov@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> [eblake: comment grammar fix] Signed-off-by: Eric Blake <eblake@redhat.com>
2019-07-22block: Only the main loop can change AioContextsMax Reitz
bdrv_set_aio_context_ignore() can only work in the main loop: bdrv_drained_begin() only works in the main loop and the node's (old) AioContext; and bdrv_drained_end() really only works in the main loop and the node's (new) AioContext (contrary to its current comment, which is just wrong). Consequentially, bdrv_set_aio_context_ignore() must be called from the main loop. Luckily, assuming that we can make block graph changes only from the main loop as well, all its callers do that already. Note that changing a node's context in a sense is an operation that changes the block graph, so it actually makes sense to require this function to be called from the main loop. Also, fix bdrv_drained_end()'s description. You can only use it from the main loop or the node's AioContext, and in the latter case, the whole subtree must be in the same context. Fixes: e037c09c78520cbdb6da7cfc6ad0256d5870b814 Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20190722133054.21781-3-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-07-19block: Do not poll in bdrv_do_drained_end()Max Reitz
We should never poll anywhere in bdrv_do_drained_end() (including its recursive callees like bdrv_drain_invoke()), because it does not cope well with graph changes. In fact, it has been written based on the postulation that no graph changes will happen in it. Instead, the callers that want to poll must poll, i.e. all currently globally available wrappers: bdrv_drained_end(), bdrv_subtree_drained_end(), bdrv_unapply_subtree_drain(), and bdrv_drain_all_end(). Graph changes there do not matter. They can poll simply by passing a pointer to a drained_end_counter and wait until it reaches 0. This patch also adds a non-polling global wrapper for bdrv_do_drained_end() that takes a drained_end_counter pointer. We need such a variant because now no function called anywhere from bdrv_do_drained_end() must poll. This includes BdrvChildRole.drained_end(), which already must not poll according to its interface documentation, but bdrv_child_cb_drained_end() just violates that by invoking bdrv_drained_end() (which does poll). Therefore, BdrvChildRole.drained_end() must take a *drained_end_counter parameter, which bdrv_child_cb_drained_end() can pass on to the new bdrv_drained_end_no_poll() function. Note that we now have a pattern of all drained_end-related functions either polling or receiving a *drained_end_counter to let the caller poll based on that. A problem with a single poll loop is that when the drained section in bdrv_set_aio_context_ignore() ends, some nodes in the subgraph may be in the old contexts, while others are in the new context already. To let the collective poll in bdrv_drained_end() work correctly, we must not hold a lock to the old context, so that the old context can make progress in case it is different from the current context. (In the process, remove the comment saying that the current context is always the old context, because it is wrong.) In all other places, all nodes in a subtree must be in the same context, so we can just poll that. The exception of course is bdrv_drain_all_end(), but that always runs in the main context, so we can just poll NULL (like bdrv_drain_all_begin() does). Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-07-19block: Make bdrv_parent_drained_[^_]*() staticMax Reitz
These functions are not used outside of block/io.c, there is no reason why they should be globally available. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-07-19block: Introduce BdrvChild.parent_quiesce_counterMax Reitz
Commit 5cb2737e925042e6c7cd3fb0b01313950b03cddf laid out why bdrv_do_drained_end() must decrement the quiesce_counter after bdrv_drain_invoke(). It did not give a very good reason why it has to happen after bdrv_parent_drained_end(), instead only claiming symmetry to bdrv_do_drained_begin(). It turns out that delaying it for so long is wrong. Situation: We have an active commit job (i.e. a mirror job) from top to base for the following graph: filter | [file] | v top --[backing]--> base Now the VM is closed, which results in the job being cancelled and a bdrv_drain_all() happening pretty much simultaneously. Beginning the drain means the job is paused once whenever one of its nodes is quiesced. This is reversed when the drain ends. With how the code currently is, after base's drain ends (which means that it will have unpaused the job once), its quiesce_counter remains at 1 while it goes to undrain its parents (bdrv_parent_drained_end()). For some reason or another, undraining filter causes the job to be kicked and enter mirror_exit_common(), where it proceeds to invoke block_job_remove_all_bdrv(). Now base will be detached from the job. Because its quiesce_counter is still 1, it will unpause the job once more. So in total, undraining base will unpause the job twice. Eventually, this will lead to the job's pause_count going negative -- well, it would, were there not an assertion against this, which crashes qemu. The general problem is that if in bdrv_parent_drained_end() we undrain parent A, and then undrain parent B, which then leads to A detaching the child, bdrv_replace_child_noperm() will undrain A as if we had not done so yet; that is, one time too many. It follows that we cannot decrement the quiesce_counter after invoking bdrv_parent_drained_end(). Unfortunately, decrementing it before bdrv_parent_drained_end() would be wrong, too. Imagine the above situation in reverse: Undraining A leads to B detaching the child. If we had already decremented the quiesce_counter by that point, bdrv_replace_child_noperm() would undrain B one time too little; because it expects bdrv_parent_drained_end() to issue this undrain. But bdrv_parent_drained_end() won't do that, because B is no longer a parent. Therefore, we have to do something else. This patch opts for introducing a second quiesce_counter that counts how many times a child's parent has been quiesced (though c->role->drained_*). With that, bdrv_replace_child_noperm() just has to undrain the parent exactly that many times when removing a child, and it will always be right. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-07-15block: Add BDS.never_freezeMax Reitz
The commit and the mirror block job must be able to drop their filter node at any point. However, this will not be possible if any of the BdrvChild links to them is frozen. Therefore, we need to prevent them from ever becoming frozen. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20190703172813.6868-2-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-07-02block: include base when checking image chain for block allocationAndrey Shinkevich
This patch is used in the 'block/stream: introduce a bottom node' that is following. Instead of the base node, the caller may pass the node that has the base as its backing image to the function bdrv_is_allocated_above() with a new parameter include_base = true and get rid of the dependency on the base that may change during commit/stream parallel jobs. Now, if the specified base is not found in the backing image chain, the QEMU will abort. Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 1559152576-281803-2-git-send-email-andrey.shinkevich@virtuozzo.com [mreitz: Squashed in the following as a rebase on conflicting patches:] Message-id: e3cf99ae-62e9-8b6e-5a06-d3c8b9363b85@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-06-18block: Add bdrv_child_refresh_perms()Max Reitz
If a block node uses bdrv_child_try_set_perm() to change the permission it takes on its child, the result may be very short-lived. If anything makes the block layer recalculate the permissions internally, it will invoke the node driver's .bdrv_child_perm() implementation. The permission/shared permissions masks that returns will then override the values previously passed to bdrv_child_try_set_perm(). If drivers want a child edge to have specific values for the permissions/shared permissions mask, it must return them in .bdrv_child_perm(). Consequentially, there is no need for them to pass the same values to bdrv_child_try_set_perm() then: It is better to have a function that invokes .bdrv_child_perm() and calls bdrv_child_try_set_perm() with the result. This patch adds such a function under the name of bdrv_child_refresh_perms(). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-18block: drop bs->jobVladimir Sementsov-Ogievskiy
Drop remaining users of bs->job: 1. assertions actually duplicated by assert(!bs->refcnt) 2. trace-point seems not enough reason to change stream_start to return BlockJob pointer 3. Restricting creation of two jobs based on same bs is bad idea, as 3.1 Some jobs creates filters to be their main node, so, this check don't actually prevent creating second job on same real node (which will create another filter node) (but I hope it is restricted by other mechanisms) 3.2 Even without bs->job we have two systems of permissions: op-blockers and BLK_PERM 3.3 We may want to run several jobs on one node one day And finally, drop bs->job pointer itself. Hurrah! Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-18blockdev: blockdev_mark_auto_del: drop usage of bs->jobVladimir Sementsov-Ogievskiy
We are going to remove bs->job pointer. Drop it's usage in blockdev_mark_auto_del: instead of looking at bs->job let's check all jobs for references to bs. Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-18block/replication: drop usage of bs->jobVladimir Sementsov-Ogievskiy
We are going to remove bs->job pointer. Drop it's usage in replication code. Additionally we have to return job pointer from some mirror APIs. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-12Include qemu-common.h exactly where neededMarkus Armbruster
No header includes qemu-common.h after this commit, as prescribed by qemu-common.h's file comment. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-5-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and net/tap-bsd.c fixed up]
2019-06-04block/io: bdrv_pdiscard: support int64_t bytes parameterVladimir Sementsov-Ogievskiy
This fixes at least one overflow in qcow2_process_discards, which passes 64bit region length to bdrv_pdiscard where bytes (or sectors in the past) parameter is int since its introduction in 0b919fae. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04block: Remove bdrv_set_aio_context()Kevin Wolf
All callers of bdrv_set_aio_context() are eliminated now, they have moved to bdrv_try_set_aio_context() and related safe functions. Remove bdrv_set_aio_context(). With this, we can now know that the .set_aio_ctx callback must be present in bdrv_set_aio_context_ignore() because bdrv_can_set_aio_context() would have returned false previously, so instead of checking the condition, we can assert it. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04block: Adjust AioContexts when attaching nodesKevin Wolf
So far, we only made sure that updating the AioContext of a node affected the whole subtree. However, if a node is newly attached to a new parent, we also need to make sure that both the subtree of the node and the parent are in the same AioContext. This tries to move the new child node to the parent AioContext and returns an error if this isn't possible. BlockBackends now actually apply their AioContext to their root node. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04nvme: add Get/Set Feature Timestamp supportKenneth Heitke
Signed-off-by: Kenneth Heitke <kenneth.heitke@intel.com> Reviewed-by: Klaus Birkelund Jensen <klaus.jensen@cnexlabs.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04block/linux-aio: Drop unused BlockAIOCB submission methodJulia Suvorova
Callback-based laio_submit() and laio_cancel() were left after rewriting Linux AIO backend to coroutines in hope that they would be used in other code that could bypass coroutines. They can be safely removed because they have not been used since that time. Signed-off-by: Julia Suvorova <jusual@mail.ru> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04block: avoid recursive block_status call if possibleVladimir Sementsov-Ogievskiy
drv_co_block_status digs bs->file for additional, more accurate search for hole inside region, reported as DATA by bs since 5daa74a6ebc. This accuracy is not free: assume we have qcow2 disk. Actually, qcow2 knows, where are holes and where is data. But every block_status request calls lseek additionally. Assume a big disk, full of data, in any iterative copying block job (or img convert) we'll call lseek(HOLE) on every iteration, and each of these lseeks will have to iterate through all metadata up to the end of file. It's obviously ineffective behavior. And for many scenarios we don't need this lseek at all. However, lseek is needed when we have metadata-preallocated image. So, let's detect metadata-preallocation case and don't dig qcow2's protocol file in other cases. The idea is to compare allocation size in POV of filesystem with allocations size in POV of Qcow2 (by refcounts). If allocation in fs is significantly lower, consider it as metadata-preallocation case. 102 iotest changed, as our detector can't detect shrinked file as metadata-preallocation, which don't seem to be wrong, as with metadata preallocation we always have valid file length. Two other iotests have a slight change in their QMP output sequence: Active 'block-commit' returns earlier because the job coroutine yields earlier on a blocking operation. This operation is loading the refcount blocks in qcow2_detect_metadata_preallocation(). Suggested-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-05-20block: Propagate AioContext change to parentsKevin Wolf
All block nodes and users in any connected component of the block graph must be in the same AioContext, so changing the AioContext of one node must not only change all of its children, but all of its parents (and in turn their children etc.) as well. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-05-20block: Make bdrv_attach/detach_aio_context() staticKevin Wolf
Since commit b97511c7bc8, there is no reason for block drivers any more to call these functions (see the function comment in block_int.h). They are now just internal helper functions for bdrv_set_aio_context() and can be made static. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-05-20block: Add bdrv_try_set_aio_context()Kevin Wolf
Eventually, we want to make sure that all parents and all children of a node are in the same AioContext as the node itself. This means that changing the AioContext may fail because one of the other involved parties (e.g. a guest device that was configured with an iothread) cannot allow switching to a different AioContext. Introduce a set of functions that allow to first check whether all involved nodes can switch to a new context and only then do the actual switch. The check recursively covers children and parents. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-05-13Merge remote-tracking branch 'remotes/armbru/tags/pull-misc-2019-05-13' into ↵Peter Maydell
staging Miscellaneous patches for 2019-05-13 # gpg: Signature made Mon 13 May 2019 08:04:02 BST # gpg: using RSA key 3870B400EB918653 # gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full] # gpg: aka "Markus Armbruster <armbru@pond.sub.org>" [full] # Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653 * remotes/armbru/tags/pull-misc-2019-05-13: Clean up decorations and whitespace around header guards Normalize header guard symbol definition. Clean up ill-advised or unusual header guards Clean up header guards that don't match their file name target/xtensa: Clean up core-isa.h header guards linux-user/nios2 linux-user/riscv: Clean up header guards authz: Normalize #include "authz/trace.h" to "trace.h" Use #include "..." for our own headers, <...> for others Clean up includes Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-05-13Clean up decorations and whitespace around header guardsMarkus Armbruster
Cleaned up with scripts/clean-header-guards.pl. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190315145123.28030-9-armbru@redhat.com>
2019-05-10block: Remove bdrv_read() and bdrv_write()Alberto Garcia
No one is using these functions anymore, all callers have switched to the byte-based bdrv_pread() and bdrv_pwrite() Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-05-07qemu-nbd: Look up flag names in arrayMax Reitz
The existing code to convert flag bits into strings looks a bit strange now, and if we ever add more flags, it will look even stranger. Prevent that from happening by making it look up the flag names in an array. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20190405191635.25740-1-mreitz@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2019-04-30block: introduce byte-based io helpersVladimir Sementsov-Ogievskiy
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-04-18block/qapi: Clean up how we print to monitor or stdoutMarkus Armbruster
bdrv_snapshot_dump(), bdrv_image_info_specific_dump(), bdrv_image_info_dump() and their helpers take an fprintf()-like callback and a FILE * to pass to it. hmp.c passes monitor_printf() cast to fprintf_function and the current monitor cast to FILE *. qemu-img.c and qemu-io-cmds.c pass fprintf and stdout. The type-punning is technically undefined behaviour, but works in practice. Clean up: drop the callback, and call qemu_printf() instead. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190417191805.28198-8-armbru@redhat.com>
2019-04-18qsp: Simplify how qsp_report() printsMarkus Armbruster
qsp_report() takes an fprintf()-like callback and a FILE * to pass to it. Its only caller hmp_sync_profile() passes monitor_fprintf() and the current monitor cast to FILE *. monitor_fprintf() casts it right back, and is otherwise identical to monitor_printf(). The type-punning is ugly. Drop the callback, and call qemu_printf() instead. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190417191805.28198-7-armbru@redhat.com>
2019-03-26file-posix: Support BDRV_REQ_NO_FALLBACK for zero writesKevin Wolf
We know that the kernel implements a slow fallback code path for BLKZEROOUT, so if BDRV_REQ_NO_FALLBACK is given, we shouldn't call it. The other operations we call in the context of .bdrv_co_pwrite_zeroes should usually be quick, so no modification should be needed for them. If we ever notice that there are additional problematic cases, we can still make these conditional as well. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Eric Blake <eblake@redhat.com>
2019-03-26block: Add BDRV_REQ_NO_FALLBACKKevin Wolf
For qemu-img convert, we want an operation that zeroes out the whole image if this can be done efficiently, but that returns an error otherwise so we don't write explicit zeroes and immediately overwrite them with the real data, potentially doubling the amount of data to be written. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Eric Blake <eblake@redhat.com>
2019-03-13Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into ↵Peter Maydell
staging Pull request # gpg: Signature made Tue 12 Mar 2019 20:23:08 GMT # gpg: using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E # gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full] # Primary key fingerprint: FAEB 9711 A12C F475 812F 18F2 88A9 064D 1835 61EB # Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76 CBD0 7DEF 8106 AAFC 390E * remotes/jnsnow/tags/bitmaps-pull-request: (22 commits) tests/qemu-iotests: add bitmap resize test 246 block/qcow2-bitmap: Allow resizes with persistent bitmaps block/qcow2-bitmap: Don't check size for IN_USE bitmap docs/interop/qcow2: Improve bitmap flag in_use specification bitmaps: Fix typo in function name block/dirty-bitmaps: implement inconsistent bit block/dirty-bitmaps: disallow busy bitmaps as merge source block/dirty-bitmaps: prohibit removing readonly bitmaps block/dirty-bitmaps: prohibit readonly bitmaps for backups block/dirty-bitmaps: add block_dirty_bitmap_check function block/dirty-bitmap: add inconsistent status block/dirty-bitmaps: add inconsistent bit iotests: add busy/recording bit test to 124 blockdev: remove unused paio parameter documentation block/dirty-bitmaps: move comment block block/dirty-bitmaps: unify qmp_locked and user_locked calls block/dirty-bitmap: explicitly lock bitmaps with successors nbd: change error checking order for bitmaps block/dirty-bitmap: change semantics of enabled predicate block/dirty-bitmap: remove set/reset assertions against enabled bit ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org> # Conflicts: # tests/qemu-iotests/group