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2024-05-28qapi: blockdev-backup: add discard-source parameterVladimir Sementsov-Ogievskiy
Add a parameter that enables discard-after-copy. That is mostly useful in "push backup with fleecing" scheme, when source is snapshot-access format driver node, based on copy-before-write filter snapshot-access API: [guest] [snapshot-access] ~~ blockdev-backup ~~> [backup target] | | | root | file v v [copy-before-write] | | | file | target v v [active disk] [temp.img] In this case discard-after-copy does two things: - discard data in temp.img to save disk space - avoid further copy-before-write operation in discarded area Note that we have to declare WRITE permission on source in copy-before-write filter, for discard to work. Still we can't take it unconditionally, as it will break normal backup from RO source. So, we have to add a parameter and pass it thorough bdrv_open flags. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Fiona Ebner <f.ebner@proxmox.com> Tested-by: Fiona Ebner <f.ebner@proxmox.com> Acked-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20240313152822.626493-5-vsementsov@yandex-team.ru> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
2024-05-27block: Improve error message when external snapshot can't flushMarkus Armbruster
external_snapshot_action() reports bdrv_flush() failure to its caller as An IO error has occurred The errno code returned by bdrv_flush() is lost. Improve this to Write to node '<device or node name>' failed: <description of errno> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20240513141703.549874-2-armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2024-04-24qapi: Inline and remove QERR_DEVICE_HAS_NO_MEDIUM definitionPhilippe Mathieu-Daudé
Address the comment added in commit 4629ed1e98 ("qerror: Finally unused, clean up"), from 2015: /* * These macros will go away, please don't use * in new code, and do not add new ones! */ Mechanical transformation using sed, and manual cleanup. Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20240312141343.3168265-4-armbru@redhat.com>
2024-03-18blockdev: Fix blockdev-snapshot-sync error reporting for no mediumMarkus Armbruster
When external_snapshot_abort() rejects a BlockDriverState without a medium, it creates an error like this: error_setg(errp, "Device '%s' has no medium", device); Trouble is @device can be null. My system formats null as "(null)", but other systems might crash. Reproducer: 1. Create a block device without a medium -> {"execute": "blockdev-add", "arguments": {"driver": "host_cdrom", "node-name": "blk0", "filename": "/dev/sr0"}} <- {"return": {}} 3. Attempt to snapshot it -> {"execute":"blockdev-snapshot-sync", "arguments": { "node-name": "blk0", "snapshot-file":"/tmp/foo.qcow2","format":"qcow2"}} <- {"error": {"class": "GenericError", "desc": "Device '(null)' has no medium"}} Broken when commit 0901f67ecdb made @device optional. Use bdrv_get_device_or_node_name() instead. Now it fails as it should: <- {"error": {"class": "GenericError", "desc": "Device 'blk0' has no medium"}} Fixes: 0901f67ecdb7 ("qmp: Allow to take external snapshots on bs graphs node.") Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20240306142831.2514431-1-armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2024-03-09blockdev: Fix block_resize error reporting for op blockersMarkus Armbruster
When block_resize() runs into an op blocker, it creates an error like this: error_setg(errp, "Device '%s' is in use", device); Trouble is @device can be null. My system formats null as "(null)", but other systems might crash. Reproducer: 1. Create two block devices -> {"execute": "blockdev-add", "arguments": {"driver": "file", "node-name": "blk0", "filename": "64k.img"}} <- {"return": {}} -> {"execute": "blockdev-add", "arguments": {"driver": "file", "node-name": "blk1", "filename": "m.img"}} <- {"return": {}} 2. Put a blocker on one them -> {"execute": "blockdev-mirror", "arguments": {"job-id": "job0", "device": "blk0", "target": "blk1", "sync": "full"}} {"return": {}} -> {"execute": "job-pause", "arguments": {"id": "job0"}} {"return": {}} -> {"execute": "job-complete", "arguments": {"id": "job0"}} {"return": {}} Note: job events elided for brevity. 3. Attempt to resize -> {"execute": "block_resize", "arguments": {"node-name": "blk1", "size":32768}} <- {"error": {"class": "GenericError", "desc": "Device '(null)' is in use"}} Broken when commit 3b1dbd11a60 made @device optional. Fixed in commit ed3d2ec98a3 (block: Add errp to b{lk,drv}_truncate()), except for this one instance. Fix it by using the error message provided by the op blocker instead, so it fails like this: <- {"error": {"class": "GenericError", "desc": "Node 'blk1' is busy: block device is in use by block job: mirror"}} Fixes: 3b1dbd11a60d (qmp: Allow block_resize to manipulate bs graph nodes.) Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Michael Tokarev <mjt@tls.msk.ru> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2024-01-26stream: Allow users to request only format driver names in backing file formatPeter Krempa
Introduce a new flag 'backing-mask-protocol' for the block-stream QMP command which instructs the internals to use 'raw' instead of the protocol driver in case when a image is used without a dummy 'raw' wrapper. The flag is designed such that it can be always asserted by management tools even when there isn't any update to backing files. The flag will be used by libvirt so that the backing images still reference the proper format even when libvirt will stop using the dummy raw driver (raw driver with no other config). Libvirt needs this so that the images stay compatible with older libvirt versions which didn't expect that a protocol driver name can appear in the backing file format field. Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-ID: <bbee9a0a59748a8893289bf8249f568f0d587e62.1701796348.git.pkrempa@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2024-01-26commit: Allow users to request only format driver names in backing file formatPeter Krempa
Introduce a new flag 'backing-mask-protocol' for the block-commit QMP command which instructs the internals to use 'raw' instead of the protocol driver in case when a image is used without a dummy 'raw' wrapper. The flag is designed such that it can be always asserted by management tools even when there isn't any update to backing files. The flag will be used by libvirt so that the backing images still reference the proper format even when libvirt will stop using the dummy raw driver (raw driver with no other config). Libvirt needs this so that the images stay compatible with older libvirt versions which didn't expect that a protocol driver name can appear in the backing file format field. Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-ID: <2cb46e37093ce793ea1604abc8bbb90f4c8e434b.1701796348.git.pkrempa@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-12-21block: remove bdrv_co_lock()Stefan Hajnoczi
The bdrv_co_lock() and bdrv_co_unlock() functions are already no-ops. Remove them. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-ID: <20231205182011.1976568-8-stefanha@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-12-21block: remove AioContext lockingStefan Hajnoczi
This is the big patch that removes aio_context_acquire()/aio_context_release() from the block layer and affected block layer users. There isn't a clean way to split this patch and the reviewers are likely the same group of people, so I decided to do it in one patch. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Paul Durrant <paul@xen.org> Message-ID: <20231205182011.1976568-7-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-12-21graph-lock: remove AioContext lockingStefan Hajnoczi
Stop acquiring/releasing the AioContext lock in bdrv_graph_wrlock()/bdrv_graph_unlock() since the lock no longer has any effect. The distinction between bdrv_graph_wrunlock() and bdrv_graph_wrunlock_ctx() becomes meaningless and they can be collapsed into one function. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231205182011.1976568-6-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-12-12block: Fix AioContext locking in qmp_block_resize()Kevin Wolf
The AioContext must be unlocked before calling blk_co_unref(), because it takes the AioContext lock internally in blk_unref_bh(), which is scheduled in the main thread. If we don't unlock, the AioContext is locked twice and nested event loops such as in bdrv_graph_wrlock() will deadlock. Cc: <qemu-stable@nongnu.org> Fixes: https://issues.redhat.com/browse/RHEL-15965 Fixes: 0c7d204f50c382c6baac8c94bd57af4a022b3888 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-ID: <20231208124352.30295-1-kwolf@redhat.com>
2023-11-21block: Fix deadlocks in bdrv_graph_wrunlock()Kevin Wolf
bdrv_graph_wrunlock() calls aio_poll(), which may run callbacks that have a nested event loop. Nested event loops can depend on other iothreads making progress, so in order to allow them to make progress it must not hold the AioContext lock of another thread while calling aio_poll(). This introduces a @bs parameter to bdrv_graph_wrunlock() whose AioContext is temporarily dropped (which matches bdrv_graph_wrlock()), and a bdrv_graph_wrunlock_ctx() that can be used if the BlockDriverState doesn't necessarily exist any more when unlocking. This also requires a change to bdrv_schedule_unref(), which was relying on the incorrectly taken lock. It needs to take the lock itself now. While this is a separate bug, it can't be fixed a separate patch because otherwise the intermediate state would either deadlock or try to release a lock that we don't even hold. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231115172012.112727-3-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> [kwolf: Fixed up bdrv_schedule_unref()] Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07block: Mark bdrv_replace_node() GRAPH_WRLOCKKevin Wolf
Instead of taking the writer lock internally, require callers to already hold it when calling bdrv_replace_node(). Its callers may already want to hold the graph lock and so wouldn't be able to call functions that take it internally. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231027155333.420094-17-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07block: Mark bdrv_chain_contains() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_chain_contains() need to hold a reader lock for the graph because it calls bdrv_filter_or_cow_bs(), which accesses bs->file/backing. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231027155333.420094-11-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07block: Mark bdrv_skip_filters() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_skip_filters() need to hold a reader lock for the graph because it calls bdrv_filter_child(), which accesses bs->file/backing. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231027155333.420094-9-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07block: Mark bdrv_skip_implicit_filters() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_skip_implicit_filters() need to hold a reader lock for the graph because it calls bdrv_filter_child(), which accesses bs->file/backing. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231027155333.420094-8-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07block: Mark bdrv_filter_or_cow_bs() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_filter_or_cow_bs() need to hold a reader lock for the graph because it calls bdrv_filter_or_cow_child(), which accesses bs->file/backing. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231027155333.420094-7-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07block: Mark bdrv_has_zero_init() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_has_zero_init() need to hold a reader lock for the graph because it calls bdrv_filter_bs(), which accesses bs->file/backing. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20231027155333.420094-3-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07hw/xen: automatically assign device index to block devicesDavid Woodhouse
There's no need to force the user to assign a vdev. We can automatically assign one, starting at xvda and searching until we find the first disk name that's unused. This means we can now allow '-drive if=xen,file=xxx' to work without an explicit separate -driver argument, just like if=virtio. Rip out the legacy handling from the xenpv machine, which was scribbling over any disks configured by the toolstack, and didn't work with anything but raw images. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Paul Durrant <paul@xen.org>
2023-10-31blockjob: introduce block-job-change QMP commandFiona Ebner
which will allow changing job-type-specific options after job creation. In the JobVerbTable, the same allow bits as for set-speed are used, because set-speed can be considered an existing change command. Signed-off-by: Fiona Ebner <f.ebner@proxmox.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-ID: <20231031135431.393137-2-f.ebner@proxmox.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31blockdev: mirror: avoid potential deadlock when using iothreadFiona Ebner
The bdrv_getlength() function is a generated co-wrapper and uses AIO_WAIT_WHILE() to wait for the spawned coroutine. AIO_WAIT_WHILE() expects the lock to be acquired exactly once. Fix a case where it may be acquired twice. This can happen when the source node is explicitly specified as the @replaces parameter or if the source node is a filter node. Signed-off-by: Fiona Ebner <f.ebner@proxmox.com> Message-ID: <20231019131936.414246-4-f.ebner@proxmox.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12block: Mark bdrv_op_is_blocked() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_op_is_blocked() need to hold a reader lock for the graph because it calls bdrv_get_device_or_node_name(), which accesses the parents list of a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20230929145157.45443-18-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12block: Mark bdrv_refresh_filename() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_refresh_filename() need to hold a reader lock for the graph because it accesses the children list of a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20230929145157.45443-11-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12block: Mark bdrv_get_xdbg_block_graph() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_get_xdbg_block_graph() need to hold a reader lock for the graph because it accesses the children list of a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20230929145157.45443-10-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12block: Mark bdrv_snapshot_fallback() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_snapshot_fallback() need to hold a reader lock for the graph because it accesses the children list of a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20230929145157.45443-8-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12block: Mark bdrv_first_blk() and bdrv_is_root_node() GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_first_blk() and bdrv_is_root_node() need to hold a reader lock for the graph. These functions are the only functions in block-backend.c that access the parent list of a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20230929145157.45443-5-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-20block: Mark bdrv_add/del_child() and caller GRAPH_WRLOCKKevin Wolf
The functions read the parents list in the generic block layer, so we need to hold the graph lock already there. The BlockDriver implementations actually modify the graph, so it has to be a writer lock. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-ID: <20230911094620.45040-22-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-20block: Mark bdrv_get_cumulative_perm() and callers GRAPH_RDLOCKKevin Wolf
The function reads the parents list, so it needs to hold the graph lock. This happens to result in BlockDriver.bdrv_set_perm() to be called with the graph lock held. For consistency, make it the same for all of the BlockDriver callbacks for updating permissions and annotate the function pointers with GRAPH_RDLOCK_PTR. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-ID: <20230911094620.45040-15-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-06-02cutils: Adjust signature of parse_uint[_full]Eric Blake
It's already confusing that we have two very similar functions for wrapping the parse of a 64-bit unsigned value, differing mainly on whether they permit leading '-'. Adjust the signature of parse_uint() and parse_uint_full() to be like all of qemu_strto*(): put the result parameter last, use the same types (uint64_t and unsigned long long have the same width, but are not always the same type), and mark endptr const (this latter change only affects the rare caller of parse_uint). Adjust all callers in the tree. While at it, note that since cutils.c already includes: QEMU_BUILD_BUG_ON(sizeof(int64_t) != sizeof(long long)); we are guaranteed that the result of parse_uint* cannot exceed UINT64_MAX (or the build would have failed), so we can drop pre-existing dead comparisons in opts-visitor.c that were never false. Reviewed-by: Hanna Czenczek <hreitz@redhat.com> Message-Id: <20230522190441.64278-8-eblake@redhat.com> [eblake: Drop dead code spotted by Markus] Signed-off-by: Eric Blake <eblake@redhat.com>
2023-05-30block: Take main AioContext lock when calling bdrv_open()Kevin Wolf
The function documentation already says that all callers must hold the main AioContext lock, but not all of them do. This can cause assertion failures when functions called by bdrv_open() try to drop the lock. Fix a few more callers to take the lock before calling bdrv_open(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230525124713.401149-4-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19blockdev: qmp_transaction: drop extra generic layerVladimir Sementsov-Ogievskiy
Let's simplify things: First, actions generally don't need access to common BlkActionState structure. The only exclusion are backup actions that need block_job_txn. Next, for transaction actions of Transaction API is more native to allocated state structure in the action itself. So, do the following transformation: 1. Let all actions be represented by a function with corresponding structure as arguments. 2. Instead of array-map marshaller, let's make a function, that calls corresponding action directly. 3. BlkActionOps and BlkActionState structures become unused Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20230510150624.310640-7-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19blockdev: use state.bitmap in block-dirty-bitmap-add actionVladimir Sementsov-Ogievskiy
Other bitmap related actions use the .bitmap pointer in .abort action, let's do same here: 1. It helps further refactoring, as bitmap-add is the only bitmap action that uses state.action in .abort 2. It must be safe: transaction actions rely on the fact that on .abort() the state is the same as at the end of .prepare(), so that in .abort() we could precisely rollback the changes done by .prepare(). The only way to remove the bitmap during transaction should be block-dirty-bitmap-remove action, but it postpones actual removal to .commit(), so we are OK on any rollback path. (Note also that bitmap-remove is the only bitmap action that has .commit() phase, except for simple g_free the state on .clean()) 3. Again, other bitmap actions behave this way: keep the bitmap pointer during the transaction. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20230510150624.310640-6-vsementsov@yandex-team.ru> [kwolf: Also remove the now unused BlockDirtyBitmapState.prepared] Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19blockdev: transaction: refactor handling transaction propertiesVladimir Sementsov-Ogievskiy
Only backup supports GROUPED mode. Make this logic more clear. And avoid passing extra thing to each action. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20230510150624.310640-5-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19blockdev: qmp_transaction: refactor loop to classic forVladimir Sementsov-Ogievskiy
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230510150624.310640-4-vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19blockdev: transactions: rename some thingsVladimir Sementsov-Ogievskiy
Look at qmp_transaction(): dev_list is not obvious name for list of actions. Let's look at qapi spec, this argument is "actions". Let's follow the common practice of using same argument names in qapi scheme and code. To be honest, rename props to properties for same reason. Next, we have to rename global map of actions, to not conflict with new name for function argument. Rename also dev_entry loop variable accordingly to new name of the list. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230510150624.310640-3-vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19blockdev: refactor transaction to use Transaction APIVladimir Sementsov-Ogievskiy
We are going to add more block-graph modifying transaction actions, and block-graph modifying functions are already based on Transaction API. Next, we'll need to separately update permissions after several graph-modifying actions, and this would be simple with help of Transaction API. So, now let's just transform what we have into new-style transaction actions. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20230510150624.310640-2-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10block: Mark bdrv_recurse_can_replace() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_recurse_can_replace() need to hold a reader lock for the graph because it accesses the children list of a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20230504115750.54437-20-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10block: Don't call no_coroutine_fns in qmp_block_resize()Kevin Wolf
This QMP handler runs in a coroutine, so it must use the corresponding no_co_wrappers instead. Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2185688 Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20230504115750.54437-5-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10block: Fix use after free in blockdev_mark_auto_del()Kevin Wolf
job_cancel_locked() drops the job list lock temporarily and it may call aio_poll(). We must assume that the list has changed after this call. Also, with unlucky timing, it can end up freeing the job during job_completed_txn_abort_locked(), making the job pointer invalid, too. For both reasons, we can't just continue at block_job_next_locked(job). Instead, start at the head of the list again after job_cancel_locked() and skip those jobs that we already cancelled (or that are completing anyway). Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230503140142.474404-1-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_is_inserted() to co_wrapperEmanuele Giuseppe Esposito
bdrv_is_inserted() is categorized as an I/O function, and it currently doesn't run in a coroutine. We should let it take a graph rdlock since it traverses the block nodes graph, which however is only possible in a coroutine. Therefore turn it into a co_wrapper to move the actual function into a coroutine where the lock can be taken. At the same time, add also blk_is_inserted as co_wrapper_mixed, since it is called in both coroutine and non-coroutine contexts. Because now this function creates a new coroutine and polls, we need to take the AioContext lock where it is missing, for the only reason that internally c_w_mixed_bdrv_rdlock calls AIO_WAIT_WHILE and it expects to release the AioContext lock. Once the rwlock is ultimated and placed in every place it needs to be, we will poll using AIO_WAIT_WHILE_UNLOCKED and remove the AioContext lock. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230113204212.359076-5-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-01-20include/block: Untangle inclusion loopsMarkus Armbruster
We have two inclusion loops: block/block.h -> block/block-global-state.h -> block/block-common.h -> block/blockjob.h -> block/block.h block/block.h -> block/block-io.h -> block/block-common.h -> block/blockjob.h -> block/block.h I believe these go back to Emanuele's reorganization of the block API, merged a few months ago in commit d7e2fe4aac8. Fortunately, breaking them is merely a matter of deleting unnecessary includes from headers, and adding them back in places where they are now missing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20221221133551.3967339-2-armbru@redhat.com>
2022-12-15block: Fix locking in external_snapshot_prepare()Kevin Wolf
bdrv_img_create() polls internally (when calling bdrv_create(), which is a co_wrapper), so it can't be called while holding the lock of any AioContext except the current one without causing deadlocks. Drop the lock around the call in external_snapshot_prepare(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-11-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Drain individual nodes during reopenKevin Wolf
bdrv_reopen() and friends use subtree drains as a lazy way of covering all the nodes they touch. Turns out that this lazy way is a lot more complicated than just draining the nodes individually, even not accounting for the additional complexity in the drain mechanism itself. Simplify the code by switching to draining the individual nodes that are already managed in the BlockReopenQueue anyway. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-8-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-14qapi transaction: Elide redundant has_FOO in generated CMarkus Armbruster
The has_FOO for pointer-valued FOO are redundant, except for arrays. They are also a nuisance to work with. Recent commit "qapi: Start to elide redundant has_FOO in generated C" provided the means to elide them step by step. This is the step for qapi/transaction.json. Said commit explains the transformation in more detail. The invariant violations mentioned there do not occur here. In qmp_transaction(), we can't just drop parameter @has_props, since it's used to track whether @props needs to be freed. Replace it by a local variable. Cc: Kevin Wolf <kwolf@redhat.com> Cc: Hanna Reitz <hreitz@redhat.com> Cc: qemu-block@nongnu.org Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20221104160712.3005652-27-armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2022-12-14qapi block: Elide redundant has_FOO in generated CMarkus Armbruster
The has_FOO for pointer-valued FOO are redundant, except for arrays. They are also a nuisance to work with. Recent commit "qapi: Start to elide redundant has_FOO in generated C" provided the means to elide them step by step. This is the step for qapi/block*.json. Said commit explains the transformation in more detail. There is one instance of the invariant violation mentioned there: qcow2_signal_corruption() passes false, "" when node_name is an empty string. Take care to pass NULL then. The previous two commits cleaned up two more. Additionally, helper bdrv_latency_histogram_stats() loses its output parameters and returns a value instead. Cc: Kevin Wolf <kwolf@redhat.com> Cc: Hanna Reitz <hreitz@redhat.com> Cc: qemu-block@nongnu.org Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20221104160712.3005652-11-armbru@redhat.com> [Fixes for #ifndef LIBRBD_SUPPORTS_ENCRYPTION and MacOS squashed in]
2022-12-13blockdev: Clean up abuse of DriveBackup member formatMarkus Armbruster
drive-backup argument @format defaults to the format of the source unless @mode is "existing". drive_backup_prepare() implements this by copying the source's @format_name to DriveBackup member @format. It leaves @has_format false, violating the "has_format == !!format" invariant. Unclean. Falls apart when we elide @has_format (commit after next): then QAPI passes @format, which is a string constant, to g_free(). iotest 056 duly explodes. Clean it up. Since the value stored in member @format is not actually used outside this function, use a local variable instead of modifying the QAPI object. Signed-off-by: Markus Armbruster <armbru@redhat.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Hanna Reitz <hreitz@redhat.com> Cc: qemu-block@nongnu.org Message-Id: <20221104160712.3005652-9-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2022-10-27monitor: switch to *_co_* functionsAlberto Faria
Signed-off-by: Alberto Faria <afaria@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20221013123711.620631-25-pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-27block: remove bdrv_try_set_aio_context and replace it with ↵Emanuele Giuseppe Esposito
bdrv_try_change_aio_context No functional change intended. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221025084952.2139888-11-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-07job.c: enable job lock/unlock and remove Aiocontext locksEmanuele Giuseppe Esposito
Change the job_{lock/unlock} and macros to use job_mutex. Now that they are not nop anymore, remove the aiocontext to avoid deadlocks. Therefore: - when possible, remove completely the aiocontext lock/unlock pair - if it is used by some other function too, reduce the locking section as much as possible, leaving the job API outside. - change AIO_WAIT_WHILE in AIO_WAIT_WHILE_UNLOCKED, since we are not using the aiocontext lock anymore The only functions that still need the aiocontext lock are: - the JobDriver callbacks, already documented in job.h - job_cancel_sync() in replication.c is called with aio_context_lock taken, but now job is using AIO_WAIT_WHILE_UNLOCKED so we need to release the lock. Reduce the locking section to only cover the callback invocation and document the functions that take the AioContext lock, to avoid taking it twice. Also remove real_job_{lock/unlock}, as they are replaced by the public functions. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220926093214.506243-19-eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-07jobs: group together API calls under the same job lockEmanuele Giuseppe Esposito
Now that the API offers also _locked() functions, take advantage of it and give also the caller control to take the lock and call _locked functions. This makes sense especially when we have for loops, because it makes no sense to have: for(job = job_next(); ...) where each job_next() takes the lock internally. Instead we want JOB_LOCK_GUARD(); for(job = job_next_locked(); ...) In addition, protect also direct field accesses, by either creating a new critical section or widening the existing ones. Note: at this stage, job_{lock/unlock} and job lock guard macros are *nop*. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20220926093214.506243-12-eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>