aboutsummaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2022-03-04tcg/i386: Detect AVX512Richard Henderson
There are some operation sizes in some subsets of AVX512 that are missing from previous iterations of AVX. Detect them. Tested-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-03-04tcg/s390x: Implement vector NAND, NOR, EQVRichard Henderson
Tested-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-03-04tcg/ppc: Implement vector NAND, NOR, EQVRichard Henderson
Tested-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-03-04tcg: Add opcodes for vector nand, nor, eqvRichard Henderson
We've had placeholders for these opcodes for a while, and should have support on ppc, s390x and avx512 hosts. Tested-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-03-04tcg: Set MAX_OPC_PARAM_IARGS to 7Ziqiao Kong
The last entry of DEF_HELPERS_FLAGS_n is DEF_HELPER_FLAGS_7 and thus the MAX_OPC_PARAM_IARGS should be 7. Reviewed-by: Taylor Simpson <tsimpson@quicinc.com> Signed-off-by: Ziqiao Kong <ziqiaokong@gmail.com> Message-Id: <20220227113127.414533-2-ziqiaokong@gmail.com> Fixes: e6cadf49c3d ("tcg: Add support for a helper with 7 arguments") Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-03-04tcg/optimize: only read val after const checkAlex Bennée
valgrind pointed out that arg_info()->val can be undefined which will be the case if the arguments are not constant. The ordering of the checks will have ensured we never relied on an undefined value but for the sake of completeness re-order the code to be clear. Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20220209112142.3367525-1-alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-03-04block/amend: Keep strong reference to BDSHanna Reitz
Otherwise, the BDS might be freed while the job is running, which would cause a use-after-free. Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220304153729.711387-5-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block/amend: Always call .bdrv_amend_clean()Hanna Reitz
.bdrv_amend_clean() says block drivers can use it to clean up what was done in .bdrv_amend_pre_run(). Therefore, it should always be called after .bdrv_amend_pre_run(), which means we need it to call it in the JobDriver.free() callback, not in JobDriver.clean(). Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220304153729.711387-3-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04tests/qemu-iotests: Rework the checks and spots using GNU sedThomas Huth
Instead of failing the iotests if GNU sed is not available (or skipping them completely in the check-block.sh script), it would be better to simply skip the bash-based tests that rely on GNU sed, so that the other tests could still be run. Thus we now explicitely use "gsed" (either as direct program or as a wrapper around "sed" if it's the GNU version) in the spots that rely on the GNU sed behavior. Statements that use the "-r" parameter of sed have been switched to use "-E" instead, since this switch is supported by all sed versions on our supported build hosts (most also support "-r", but macOS' sed only supports "-E"). With all these changes in place, we then can also remove the sed checks from the check-block.sh script, so that "make check-block" can now be run on systems without GNU sed, too. Signed-off-by: Thomas Huth <thuth@redhat.com> Message-Id: <20220216125454.465041-1-thuth@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04iotests/graph-changes-while-io: New testHanna Reitz
Test the following scenario: 1. Some block node (null-co) attached to a user (here: NBD server) that performs I/O and keeps the node in an I/O thread 2. Repeatedly run blockdev-add/blockdev-del to add/remove an overlay to/from that node Each blockdev-add triggers bdrv_refresh_limits(), and because blockdev-add runs in the main thread, it does not stop the I/O requests. I/O can thus happen while the limits are refreshed, and when such a request sees a temporarily invalid block limit (e.g. alignment is 0), this may easily crash qemu (or the storage daemon in this case). The block layer needs to ensure that I/O requests to a node are paused while that node's BlockLimits are refreshed. Signed-off-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20220216105355.30729-4-hreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04iotests: Allow using QMP with the QSDHanna Reitz
Add a parameter to optionally open a QMP connection when creating a QemuStorageDaemon instance. Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220216105355.30729-3-hreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block: Make bdrv_refresh_limits() non-recursiveHanna Reitz
bdrv_refresh_limits() recurses down to the node's children. That does not seem necessary: When we refresh limits on some node, and then recurse down and were to change one of its children's BlockLimits, then that would mean we noticed the changed limits by pure chance. The fact that we refresh the parent's limits has nothing to do with it, so the reason for the change probably happened before this point in time, and we should have refreshed the limits then. Consequently, we should actually propagate block limits changes upwards, not downwards.  That is a separate and pre-existing issue, though, and so will not be addressed in this patch. The problem with recursing is that bdrv_refresh_limits() is not atomic. It begins with zeroing BDS.bl, and only then sets proper, valid limits. If we do not drain all nodes whose limits are refreshed, then concurrent I/O requests can encounter invalid request_alignment values and crash qemu. Therefore, a recursing bdrv_refresh_limits() requires the whole subtree to be drained, which is currently not ensured by most callers. A non-recursive bdrv_refresh_limits() only requires the node in question to not receive I/O requests, and this is done by most callers in some way or another: - bdrv_open_driver() deals with a new node with no parents yet - bdrv_set_file_or_backing_noperm() acts on a drained node - bdrv_reopen_commit() acts only on drained nodes - bdrv_append() should in theory require the node to be drained; in practice most callers just lock the AioContext, which should at least be enough to prevent concurrent I/O requests from accessing invalid limits So we can resolve the bug by making bdrv_refresh_limits() non-recursive. Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1879437 Signed-off-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20220216105355.30729-2-hreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04job.h: assertions in the callers of JobDriver function pointersEmanuele Giuseppe Esposito
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-32-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04job.h: split function pointers in JobDriverEmanuele Giuseppe Esposito
The job API will be handled separately in another serie. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-31-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block-backend-common.h: split function pointers in BlockDevOpsEmanuele Giuseppe Esposito
Assertions in the callers of the function pointrs are already added by previous patches. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20220303151616.325444-30-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block_int-common.h: assertions in the callers of BdrvChildClass function ↵Emanuele Giuseppe Esposito
pointers Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-29-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block_int-common.h: split function pointers in BdrvChildClassEmanuele Giuseppe Esposito
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-28-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block_int-common.h: assertions in the callers of BlockDriver function pointersEmanuele Giuseppe Esposito
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-27-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block_int-common.h: split function pointers in BlockDriverEmanuele Giuseppe Esposito
Similar to the header split, also the function pointers in BlockDriver can be split in I/O and global state. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-26-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block/coroutines: I/O and "I/O or GS" APIEmanuele Giuseppe Esposito
block coroutines functions run in different aiocontext, and are not protected by the BQL. Therefore are I/O. On the other side, generated_co_wrapper functions use BDRV_POLL_WHILE, meaning the caller can either be the main loop or a specific iothread. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-25-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block/copy-before-write.h: global state API + assertionsEmanuele Giuseppe Esposito
copy-before-write functions always run under BQL. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-24-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04include/block/snapshot: global state API + assertionsEmanuele Giuseppe Esposito
Snapshots run also under the BQL, so they all are in the global state API. The aiocontext lock that they hold is currently an overkill and in future could be removed. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-23-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04assertions for blockdev.h global state APIEmanuele Giuseppe Esposito
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-22-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04include/sysemu/blockdev.h: global state APIEmanuele Giuseppe Esposito
blockdev functions run always under the BQL lock. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-21-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04assertions for blockjob.h global state APIEmanuele Giuseppe Esposito
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-20-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04include/block/blockjob.h: global state APIEmanuele Giuseppe Esposito
blockjob functions run always under the BQL lock. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-19-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block.c: add assertions to static functionsEmanuele Giuseppe Esposito
Following the assertion derived from the API split, propagate the assertion also in the static functions. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-18-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04GS and IO CODE macros for blockjob_int.hEmanuele Giuseppe Esposito
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-17-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04include/block/blockjob_int.h: split header into I/O and GS APIEmanuele Giuseppe Esposito
Since the I/O functions are not many, keep a single file. Also split the function pointers in BlockJobDriver. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220303151616.325444-16-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block: introduce assert_bdrv_graph_writableEmanuele Giuseppe Esposito
We want to be sure that the functions that write the child and parent list of a bs are under BQL and drain. BQL prevents from concurrent writings from the GS API, while drains protect from I/O. TODO: drains are missing in some functions using this assert. Therefore a proper assertion will fail. Because adding drains requires additional discussions, they will be added in future series. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-15-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04IO_CODE and IO_OR_GS_CODE for block_int I/O APIEmanuele Giuseppe Esposito
Mark all I/O functions with IO_CODE, and all "I/O OR GS" with IO_OR_GS_CODE. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-14-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04assertions for block_int global state APIEmanuele Giuseppe Esposito
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-13-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04include/block/block_int: split header into I/O and global state APIEmanuele Giuseppe Esposito
Similarly to the previous patch, split block_int.h in block_int-io.h and block_int-global-state.h block_int-common.h contains the structures shared between the two headers, and the functions that can't be categorized as I/O or global state. Assertions are added in the next patch. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-12-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block.c: assertions to the block layer permissions APIEmanuele Giuseppe Esposito
Now that we "covered" the three main cases where the permission API was being used under BQL (fuse, amend and invalidate_cache), we can safely assert for the permission functions implemented in block.c Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-11-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04IO_CODE and IO_OR_GS_CODE for block-backend I/O APIEmanuele Giuseppe Esposito
Mark all I/O functions with IO_CODE, and all "I/O OR GS" with IO_OR_GS_CODE. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-10-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block/block-backend.c: assertions for block-backendEmanuele Giuseppe Esposito
All the global state (GS) API functions will check that qemu_in_main_thread() returns true. If not, it means that the safety of BQL cannot be guaranteed, and they need to be moved to I/O. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-9-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04include/sysemu/block-backend: split header into I/O and global state (GS) APIEmanuele Giuseppe Esposito
Similarly to the previous patches, split block-backend.h in block-backend-io.h and block-backend-global-state.h In addition, remove "block/block.h" include as it seems it is not necessary anymore, together with "qemu/iov.h" block-backend-common.h contains the structures shared between the two headers, and the functions that can't be categorized as I/O or global state. Assertions are added in the next patch. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-8-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04block/export/fuse.c: allow writable exports to take RESIZE permissionEmanuele Giuseppe Esposito
Allow writable exports to get BLK_PERM_RESIZE permission from creation, in fuse_export_create(). In this way, there is no need to give the permission in fuse_do_truncate(), which might be run in an iothread. Permissions should be set only in the main thread, so in any case if an iothread tries to set RESIZE, it will be blocked. Also assert in fuse_do_truncate that if we give the RESIZE permission we can then restore the original ones. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220303151616.325444-7-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04IO_CODE and IO_OR_GS_CODE for block I/O APIEmanuele Giuseppe Esposito
Mark all I/O functions with IO_CODE, and all "I/O OR GS" with IO_OR_GS_CODE. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-6-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04assertions for block global state APIEmanuele Giuseppe Esposito
All the global state (GS) API functions will check that qemu_in_main_thread() returns true. If not, it means that the safety of BQL cannot be guaranteed, and they need to be moved to I/O. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-5-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04include/block/block: split header into I/O and global state APIEmanuele Giuseppe Esposito
block.h currently contains a mix of functions: some of them run under the BQL and modify the block layer graph, others are instead thread-safe and perform I/O in iothreads. Some others can only be called by either the main loop or the iothread running the AioContext (and not other iothreads), and using them in another thread would cause deadlocks, and therefore it is not ideal to define them as I/O. It is not easy to understand which function is part of which group (I/O vs GS vs "I/O or GS"), and this patch aims to clarify it. The "GS" functions need the BQL, and often use aio_context_acquire/release and/or drain to be sure they can modify the graph safely. The I/O function are instead thread safe, and can run in any AioContext. "I/O or GS" functions run instead in the main loop or in a single iothread, and use BDRV_POLL_WHILE(). By splitting the header in two files, block-io.h and block-global-state.h we have a clearer view on what needs what kind of protection. block-common.h contains common structures shared by both headers. block.h is left there for legacy and to avoid changing all includes in all c files that use the block APIs. Assertions are added in the next patch. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-4-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04main loop: macros to mark GS and I/O functionsEmanuele Giuseppe Esposito
Righ now, IO_CODE and IO_OR_GS_CODE are nop, as there isn't really a way to check that a function is only called in I/O. On the other side, we can use qemu_in_main_thread() to check if we are in the main loop. The usage of macros makes easy to extend them in the future without making changes in all callers. They will also visually help understanding in which category each function is, without looking at the header. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-3-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04main-loop.h: introduce qemu_in_main_thread()Emanuele Giuseppe Esposito
When invoked from the main loop, this function is the same as qemu_mutex_iothread_locked, and returns true if the BQL is held. When invoked from iothreads or tests, it returns true only if the current AioContext is the Main Loop. This essentially just extends qemu_mutex_iothread_locked to work also in unit tests or other users like storage-daemon, that run in the Main Loop but end up using the implementation in stubs/iothread-lock.c. Using qemu_mutex_iothread_locked in unit tests defaults to false because they use the implementation in stubs/iothread-lock, making all assertions added in next patches fail despite the AioContext is still the main loop. See the comment in the function header for more information. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20220303151616.325444-2-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04iotests/185: Add post-READY quit testsHanna Reitz
185 tests quitting qemu while a block job is active. It does not specifically test quitting qemu while a mirror or active commit job is in its READY phase. Add two test cases for this, where we respectively mirror or commit to an external QSD instance, which provides a throttled block device. qemu is supposed to cancel the job so that it can quit as soon as possible instead of waiting for the job to complete (which it did before 6.2). Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220303164814.284974-5-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04qsd: Add --daemonizeHanna Reitz
To implement this, we reuse the existing daemonizing functions from the system emulator, which mainly do the following: - Fork off a child process, and set up a pipe between parent and child - The parent process waits until the child sends a status byte over the pipe (0 means that the child was set up successfully; anything else (including errors or EOF) means that the child was not set up successfully), and then exits with an appropriate exit status - The child process enters a new session (forking off again), changes the umask, and will ignore terminal signals from then on - Once set-up is complete, the child will chdir to /, redirect all standard I/O streams to /dev/null, and tell the parent that set-up has been completed successfully In contrast to qemu-nbd's --fork implementation, during the set up phase, error messages are not piped through the parent process. qemu-nbd mainly does this to detect errors, though (while os_daemonize() has the child explicitly signal success after set up); because we do not redirect stderr after forking, error messages continue to appear on whatever the parent's stderr was (until set up is complete). Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220303164814.284974-4-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04qsd: Add pre-init argument parsing passHanna Reitz
In contrast to qemu-nbd (where it is called --fork) and the system emulator, QSD does not have a --daemonize switch yet. Just like them, QSD allows setting up block devices and exports on the command line. When doing so, it is often necessary for whoever invoked the QSD to wait until these exports are fully set up. A --daemonize switch allows precisely this, by virtue of the parent process exiting once everything is set up. Note that there are alternative ways of waiting for all exports to be set up, for example: - Passing the --pidfile option and waiting until the respective file exists (but I do not know if there is a way of implementing this without a busy wait loop) - Set up some network server (e.g. on a Unix socket) and have the QSD connect to it after all arguments have been processed by appending corresponding --chardev and --monitor options to the command line, and then wait until the QSD connects Having a --daemonize option would make this simpler, though, without having to rely on additional tools (to set up a network server) or busy waiting. Implementing a --daemonize switch means having to fork the QSD process. Ideally, we should do this as early as possible: All the parent process has to do is to wait for the child process to signal completion of its set-up phase, and therefore there is basically no initialization that needs to be done before the fork. On the other hand, forking after initialization steps means having to consider how those steps (like setting up the block layer or QMP) interact with a later fork, which is often not trivial. In order to fork this early, we must scan the command line for --daemonize long before our current process_options() call. Instead of adding custom new code to do so, just reuse process_options() and give it a @pre_init_pass argument to distinguish the two passes. I believe there are some other switches but --daemonize that deserve parsing in the first pass: - --help and --version are supposed to only print some text and then immediately exit (so any initialization we do would be for naught). This changes behavior, because now "--blockdev inv-drv --help" will print a help text instead of complaining about the --blockdev argument. Note that this is similar in behavior to other tools, though: "--help" is generally immediately acted upon when finding it in the argument list, potentially before other arguments (even ones before it) are acted on. For example, "ls /does-not-exist --help" prints a help text and does not complain about ENOENT. - --pidfile does not need initialization, and is already exempted from the sequential order that process_options() claims to strictly follow (the PID file is only created after all arguments are processed, not at the time the --pidfile argument appears), so it makes sense to include it in the same category as --daemonize. - Invalid arguments should always be reported as soon as possible. (The same caveat with --help applies: That means that "--blockdev inv-drv --inv-arg" will now complain about --inv-arg, not inv-drv.) This patch does make some references to --daemonize without having implemented it yet, but that will happen in the next patch. Signed-off-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20220303164814.284974-3-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04os-posix: Add os_set_daemonize()Hanna Reitz
The daemonizing functions in os-posix (os_daemonize() and os_setup_post()) only daemonize the process if the static `daemonize` variable is set. Right now, it can only be set by os_parse_cmd_args(). In order to use os_daemonize() and os_setup_post() from the storage daemon to have it be daemonized, we need some other way to set this `daemonize` variable, because I would rather not tap into the system emulator's arg-parsing code. Therefore, this patch adds an os_set_daemonize() function, which will return an error on os-win32 (because daemonizing is not supported there). Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220303164814.284974-2-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04cpus: use coroutine TLS macros for iothread_lockedStefan Hajnoczi
qemu_mutex_iothread_locked() may be used from coroutines. Standard __thread variables cannot be used by coroutines. Use the coroutine TLS macros instead. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220222140150.27240-5-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04rcu: use coroutine TLS macrosStefan Hajnoczi
RCU may be used from coroutines. Standard __thread variables cannot be used by coroutines. Use the coroutine TLS macros instead. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220222140150.27240-4-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04util/async: replace __thread with QEMU TLS macrosStefan Hajnoczi
QEMU TLS macros must be used to make TLS variables safe with coroutines. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220222140150.27240-3-stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>