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2017-07-31ivshmem: fix incorrect error handling in ivshmem_recv_msg()Philippe Mathieu-Daudé1-1/+4
Screwed up in commit 3a55fc0f, v2.6.0. If qemu_chr_fe_read_all() returns -EINTR the do {} statement continues and the n accumulator used to complete reads upto sizeof(msg) is decremented by 4 (the value of EINTR on Linux). To avoid that, use simpler if() statements and continue if EINTR occured. hw/misc/ivshmem.c:650:14: warning: Loss of sign in implicit conversion } while (n < sizeof(msg)); ^ Reported-by: Clang Static Analyzer Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-07-14ivshmem: Convert to DEFINE_PROP_LINKFam Zheng1-17/+7
Unlike the usual object_property_add_link() invocations in other devices, ivshmem checks the "is mapped" state of the backend in addition to qdev_prop_allow_set_link_before_realize. To convert it without specializing DEFINE_PROP_LINK which always uses the qdev callback, move the extra check to device realize time. Signed-off-by: Fam Zheng <famz@redhat.com> Message-Id: <20170714021509.23681-12-famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14qom: enforce readonly nature of link's check callbackIgor Mammedov1-1/+1
link's check callback is supposed to verify/permit setting it, however currently nothing restricts it from misusing it and modifying target object from within. Make sure that readonly semantics are checked by compiler to prevent callback's misuse. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com> Message-Id: <20170714021509.23681-2-famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14char: avoid chardevice direct accessAnton Nefedov1-2/+2
frontends should avoid accessing CharDriver struct where possible Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1499342940-56739-6-git-send-email-anton.nefedov@virtuozzo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14char: add backend hotswap handlerAnton Nefedov1-1/+1
Frontends should have an interface to setup the handler of a backend change. The interface will be used in the next commits Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1499342940-56739-3-git-send-email-anton.nefedov@virtuozzo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-15ivshmem: use ram_from_fd()Marc-André Lureau1-8/+6
Instead of having its own mmap handling code, reuse the code from exec.c. Note: memory_region_init_ram_from_fd() adds some restrictions (check for xen, kvm sync-mmu, etc) and changes (such as size alignment). This may actually be more correct. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20170602141229.15326-6-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-02char: move CharBackend handling in char-fe unitMarc-André Lureau1-1/+1
Move all the frontend struct and methods to a seperate unit. This avoids accidentally mixing backend and frontend calls, and helps with readabilty. Make qemu_chr_replay() a macro shared by both char and char-fe. Export qemu_chr_write(), and use a macro for qemu_chr_write_all() (nb: yes, CharBackend is for char frontend :) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-06-02chardev: move headers to include/chardevMarc-André Lureau1-1/+1
So they are all in one place. The following patch will move serial & parallel declarations to the respective headers. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-05-17migration: Create migration/blocker.hJuan Quintela1-1/+1
This allows us to remove lots of includes of migration/migration.h Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-23util/cutils: Change qemu_strtosz*() from int64_t to uint64_tMarkus Armbruster1-1/+1
This will permit its use in parse_option_size(). Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> (maintainer:X86) Cc: Kevin Wolf <kwolf@redhat.com> (supporter:Block layer core) Cc: Max Reitz <mreitz@redhat.com> (supporter:Block layer core) Cc: qemu-block@nongnu.org (open list:Block layer core) Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <1487708048-2131-24-git-send-email-armbru@redhat.com>
2017-02-23util/cutils: Return qemu_strtosz*() error and value separatelyMarkus Armbruster1-2/+5
This makes qemu_strtosz(), qemu_strtosz_mebi() and qemu_strtosz_metric() similar to qemu_strtoi64(), except negative values are rejected. Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> (maintainer:X86) Cc: Kevin Wolf <kwolf@redhat.com> (supporter:Block layer core) Cc: Max Reitz <mreitz@redhat.com> (supporter:Block layer core) Cc: qemu-block@nongnu.org (open list:Block layer core) Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <1487708048-2131-23-git-send-email-armbru@redhat.com>
2017-02-23util/cutils: Let qemu_strtosz*() optionally reject trailing crapMarkus Armbruster1-4/+2
Change the qemu_strtosz() & friends to return -EINVAL when @endptr is null and the conversion doesn't consume the string completely. Matches how qemu_strtol() & friends work. Only test_qemu_strtosz_simple() passes a null @endptr. No functional change there, because its conversion consumes the string. Simplify callers that use @endptr only to fail when it doesn't point to '\0' to pass a null @endptr instead. Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> (maintainer:X86) Cc: Kevin Wolf <kwolf@redhat.com> (supporter:Block layer core) Cc: Max Reitz <mreitz@redhat.com> (supporter:Block layer core) Cc: qemu-block@nongnu.org (open list:Block layer core) Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <1487708048-2131-22-git-send-email-armbru@redhat.com>
2017-02-23util/cutils: Rename qemu_strtosz() to qemu_strtosz_MiB()Markus Armbruster1-1/+1
With qemu_strtosz(), no suffix means mebibytes. It's used rarely. I'm going to add a similar function where no suffix means bytes. Rename qemu_strtosz() to qemu_strtosz_MiB() to make the name qemu_strtosz() available for the new function. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <1487708048-2131-16-git-send-email-armbru@redhat.com>
2017-02-01pci: Convert msix_init() to Error and fix callersCao jin1-4/+4
msix_init() reports errors with error_report(), which is wrong when it's used in realize(). The same issue was fixed for msi_init() in commit 1108b2f. In order to make the API change as small as possible, leave the return value check to later patch. For some devices(like e1000e, vmxnet3, nvme) who won't fail because of msix_init's failure, suppress the error report by passing NULL error object. Bonus: add comment for msix_init. CC: Jiri Pirko <jiri@resnulli.us> CC: Gerd Hoffmann <kraxel@redhat.com> CC: Dmitry Fleytman <dmitry@daynix.com> CC: Jason Wang <jasowang@redhat.com> CC: Michael S. Tsirkin <mst@redhat.com> CC: Hannes Reinecke <hare@suse.de> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Alex Williamson <alex.williamson@redhat.com> CC: Markus Armbruster <armbru@redhat.com> CC: Marcel Apfelbaum <marcel@redhat.com> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-27char: rename CharDriverState ChardevMarc-André Lureau1-1/+1
Pick a uniform chardev type name. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-24migration: disallow migrate_add_blocker during migrationAshijeet Acharya1-4/+10
If a migration is already in progress and somebody attempts to add a migration blocker, this should rightly fail. Add an errp parameter and a retcode return value to migrate_add_blocker. Signed-off-by: John Snow <jsnow@redhat.com> Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com> Message-Id: <1484566314-3987-5-git-send-email-ashijeetacharya@gmail.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Acked-by: Greg Kurz <groug@kaod.org> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Merged with recent 'Allow invtsc migration' change
2016-11-17ivshmem: Fix 64 bit memory bar configurationZhuang Yanying1-1/+3
Device ivshmem property use64=0 is designed to make the device expose a 32 bit shared memory BAR instead of 64 bit one. The default is a 64 bit BAR, except pc-1.2 and older retain a 32 bit BAR. A 32 bit BAR can support only up to 1 GiB of shared memory. This worked as designed until commit 5400c02 accidentally flipped its sense: since then, we misinterpret use64=0 as use64=1 and vice versa. Worse, the default got flipped as well. Devices ivshmem-plain and ivshmem-doorbell are not affected. Fix by restoring the test of IVShmemState member not_legacy_32bit that got messed up in commit 5400c02. Also update its initialization for devices ivhsmem-plain and ivshmem-doorbell. Without that, they'd regress to 32 bit BARs. Signed-off-by: Zhuang Yanying <ann.zhuangyanying@huawei.com> Reviewed-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1479385863-7648-1-git-send-email-ann.zhuangyanying@huawei.com>
2016-10-24char: remove explicit_fe_open, use a set_handlers argumentMarc-André Lureau1-1/+1
No need to keep explicit_fe_open around if it affects only a qemu_chr_fe_set_handlers(). Use an additional argument instead. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20161022095318.17775-24-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24char: use qemu_chr_fe* functions with CharBackend argumentMarc-André Lureau1-10/+11
This also switches from qemu_chr_add_handlers() to qemu_chr_fe_set_handlers(). Note that qemu_chr_fe_set_handlers() now takes the focus when fe_open (qemu_chr_add_handlers() did take the focus) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20161022095318.17775-16-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24char: replace PROP_CHR with CharBackendMarc-André Lureau1-9/+9
Store the property in a CharBackend instead of CharDriverState*. This also replace systematically chr by chr.chr to access the CharDriverState*. The following patches will replace it with calls to qemu_chr_fe CharBackend functions. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20161022095318.17775-12-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-15ivshmem: Delete duplicate debug messageStefano Dong (董兴水)1-1/+0
Duplicated in commit ca0b756. Delete it. Signed-off-by: Stefano Dong (董兴水) <opensource.dxs@aliyun.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-07-21kvm-irqchip: do explicit commit when update irqPeter Xu1-0/+1
In the past, we are doing gsi route commit for each irqchip route update. This is not efficient if we are updating lots of routes in the same time. This patch removes the committing phase in kvm_irqchip_update_msi_route(). Instead, we do explicit commit after all routes updated. Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-21kvm-irqchip: simplify kvm_irqchip_add_msi_routePeter Xu1-2/+1
Changing the original MSIMessage parameter in kvm_irqchip_add_msi_route into the vector number. Vector index provides more information than the MSIMessage, we can retrieve the MSIMessage using the vector easily. This will avoid fetching MSIMessage every time before adding MSI routes. Meanwhile, the vector info will be used in the coming patches to further enable gsi route update notifications. Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-13hostmem: detect host backend memory is being used properlyXiao Guangrong1-4/+10
Currently, we use memory_region_is_mapped() to detect if the host backend memory is being used. This works if the memory is directly mapped into guest's address space, however, it is not true for nvdimm as it uses aliased memory region to map the memory. This is why this bug can happen: https://bugzilla.redhat.com/show_bug.cgi?id=1352769 Fix it by introduce a new filed, is_mapped, to HostMemoryBackend, we set/clear this filed accordingly when the device link/unlink to host backend memory Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16os-posix: include sys/mman.hPaolo Bonzini1-2/+0
qemu/osdep.h checks whether MAP_ANONYMOUS is defined, but this check is bogus without a previous inclusion of sys/mman.h. Include it in sysemu/os-posix.h and remove it from everywhere else. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-29memory: remove qemu_get_ram_fd, qemu_set_ram_fd, qemu_ram_block_host_ptrPaolo Bonzini1-3/+2
Remove direct uses of ram_addr_t and optimize memory_region_{get,set}_fd now that a MemoryRegion knows its RAMBlock directly. Reviewed-by: Marc-André Lureau <marcandre.lureau@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-04-13ivshmem: fix ivshmem-{plain,doorbell} crash without argMarc-André Lureau1-0/+30
"qemu -device ivshmem-{plain,doorbell}" will crash, because the device doesn't check that the required argument is provided. (screwed up in commit 5400c02) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com>
2016-03-24Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell1-0/+2
* Log filtering from Alex and Peter * Chardev fix from Marc-André * config.status tweak from David * Header file tweaks from Markus, myself and Veronia (Outreachy candidate) * get_ticks_per_sec() removal from Rutuja (Outreachy candidate) * Coverity fix from myself * PKE implementation from myself, based on rth's XSAVE support # gpg: Signature made Thu 24 Mar 2016 20:15:11 GMT using RSA key ID 78C7AE83 # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" * remotes/bonzini/tags/for-upstream: (28 commits) target-i386: implement PKE for TCG config.status: Pass extra parameters char: translate from QIOChannel error to errno exec: fix error handling in file_ram_alloc cputlb: modernise the debug support qemu-log: support simple pid substitution for logs target-arm: dfilter support for in_asm qemu-log: dfilter-ise exec, out_asm, op and opt_op qemu-log: new option -dfilter to limit output qemu-log: Improve the "exec" TB execution logging qemu-log: Avoid function call for disabled qemu_log_mask logging qemu-log: correct help text for -d cpu tcg: pass down TranslationBlock to tcg_code_gen util: move declarations out of qemu-common.h Replaced get_tick_per_sec() by NANOSECONDS_PER_SECOND hw: explicitly include qemu-common.h and cpu.h include/crypto: Include qapi-types.h or qemu/bswap.h instead of qemu-common.h isa: Move DMA_transfer_handler from qemu-common.h to hw/isa/isa.h Move ParallelIOArg from qemu-common.h to sysemu/char.h Move QEMU_ALIGN_*() from qemu-common.h to qemu/osdep.h ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Conflicts: scripts/clean-includes
2016-03-22util: move declarations out of qemu-common.hVeronia Bahaa1-0/+1
Move declarations out of qemu-common.h for functions declared in utils/ files: e.g. include/qemu/path.h for utils/path.c. Move inline functions out of qemu-common.h and into new files (e.g. include/qemu/bcd.h) Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22include/qemu/osdep.h: Don't include qapi/error.hMarkus Armbruster1-0/+1
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the Error typedef. Since then, we've moved to include qemu/osdep.h everywhere. Its file comment explains: "To avoid getting into possible circular include dependencies, this file should not include any other QEMU headers, with the exceptions of config-host.h, compiler.h, os-posix.h and os-win32.h, all of which are doing a similar job to this file and are under similar constraints." qapi/error.h doesn't do a similar job, and it doesn't adhere to similar constraints: it includes qapi-types.h. That's in excess of 100KiB of crap most .c files don't actually need. Add the typedef to qemu/typedefs.h, and include that instead of qapi/error.h. Include qapi/error.h in .c files that need it and don't get it now. Include qapi-types.h in qom/object.h for uint16List. Update scripts/clean-includes accordingly. Update it further to match reality: replace config.h by config-target.h, add sysemu/os-posix.h, sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h comment quoted above similarly. This reduces the number of objects depending on qapi/error.h from "all of them" to less than a third. Unfortunately, the number depending on qapi-types.h shrinks only a little. More work is needed for that one. Signed-off-by: Markus Armbruster <armbru@redhat.com> [Fix compilation without the spice devel packages. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-21ivshmem: Require master to have ID zeroMarkus Armbruster1-0/+6
Migration with ivshmem needs to be carefully orchestrated to work. Exactly one peer (the "master") migrates to the destination, all other peers need to unplug (and disconnect), migrate, plug back (and reconnect). This is sort of documented in qemu-doc. If peers connect on the destination before migration completes, the shared memory can get messed up. This isn't documented anywhere. Fix that in qemu-doc. To avoid messing up register IVPosition on migration, the server must assign the same ID on source and destination. ivshmem-spec.txt leaves ID assignment unspecified, however. Amend ivshmem-spec.txt to require the first client to receive ID zero. The example ivshmem-server complies: it always assigns the first unused ID. For a bit of additional safety, enforce ID zero for the master. This does nothing when we're not using a server, because the ID is zero for all peers then. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-40-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Drop ivshmem property x-memdevMarkus Armbruster1-20/+3
Use ivshmem-plain instead. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-39-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Clean up after the previous commitMarkus Armbruster1-197/+203
Move code to more sensible places. Use the opportunity to reorder and document IVShmemState members. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-38-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Split ivshmem-plain, ivshmem-doorbell off ivshmemMarkus Armbruster1-86/+243
ivshmem can be configured with and without interrupt capability (a.k.a. "doorbell"). The two configurations have largely disjoint options, which makes for a confusing (and badly checked) user interface. Moreover, the device can't tell the guest whether its doorbell is enabled. Create two new device models ivshmem-plain and ivshmem-doorbell, and deprecate the old one. Changes from ivshmem: * PCI revision is 1 instead of 0. The new revision is fully backwards compatible for guests. Guests may elect to require at least revision 1 to make sure they're not exposed to the funny "no shared memory, yet" state. * Property "role" replaced by "master". role=master becomes master=on, role=peer becomes master=off. Default is off instead of auto. * Property "use64" is gone. The new devices always have 64 bit BARs. Changes from ivshmem to ivshmem-plain: * The Interrupt Pin register in PCI config space is zero (does not use an interrupt pin) instead of one (uses INTA). * Property "x-memdev" is renamed to "memdev". * Properties "shm" and "size" are gone. Use property "memdev" instead. * Property "msi" is gone. The new device can't have MSI-X capability. It can't interrupt anyway. * Properties "ioeventfd" and "vectors" are gone. They're meaningless without interrupts anyway. Changes from ivshmem to ivshmem-doorbell: * Property "msi" is gone. The new device always has MSI-X capability. * Property "ioeventfd" defaults to on instead of off. * Property "size" is gone. The new device can only map all the shared memory received from the server. Guests can easily find out whether the device is configured for interrupts by checking for MSI-X capability. Note: some code added in sub-optimal places to make the diff easier to review. The next commit will move it to more sensible places. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-37-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Replace int role_val by OnOffAuto masterMarkus Armbruster1-12/+19
In preparation of making it a qdev property. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-36-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Inline check_shm_size() into its only callerMarkus Armbruster1-26/+11
Improve the error messages while there. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1458066895-20632-34-git-send-email-armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2016-03-21ivshmem: Simplify memory regions for BAR 2 (shared memory)Markus Armbruster1-30/+17
ivshmem_realize() puts the shared memory region in a container region. Used to be necessary to permit delayed mapping of the shared memory. However, we recently moved to synchronous mapping, in "ivshmem: Receive shared memory synchronously in realize()" and the commit following it. The container is redundant since then. Drop it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1458066895-20632-33-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Implement shm=... with a memory backendMarkus Armbruster1-56/+23
ivshmem has its very own code to create and map shared memory. Replace that with an implicitly created memory backend. Reduces the number of ways we create BAR 2 from three to two. The memory-backend-file is currently available only with CONFIG_LINUX, so this adds a second Linuxism to ivshmem (the other one is eventfd). Should we ever need to make it portable to systems where memory-backend-file can't be made to serve, we could create a memory-backend-shmem that allocates memory with shm_open(). Bonus fix: shared memory files are now created with permissions 0655 instead of 0777. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1458066895-20632-32-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Tighten check of property "size"Markus Armbruster1-3/+4
If size_t is narrower than 64 bits, passing uint64_t ivshmem_size to mmap() truncates. Reject such sizes. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-31-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Simplify how we cope with short reads from serverMarkus Armbruster1-59/+16
Short reads from a UNIX domain sockets are exceedingly unlikely when the other side always sends eight bytes and we always read eight bytes. We cope with them anyway. However, the code doing that is rather convoluted. Dumb it down radically. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-30-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Drop the hackish test for UNIX domain chardevMarkus Armbruster1-9/+0
The chardev must be capable of transmitting SCM_RIGHTS ancillary messages. We check it by comparing CharDriverState member filename to "unix:". That's almost as brittle as it is disgusting. When the actual transmission all happened asynchronously, this check was all we could do in realize(), and thus better than nothing. But now we receive at least one SCM_RIGHTS synchronously in realize(), it's not worth its keep anymore. Drop it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-29-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Rely on server sending the ID right after the versionMarkus Armbruster1-3/+24
The protocol specification (ivshmem-spec.txt, formerly ivshmem_device_spec.txt) has always required the ID message to be sent right at the beginning, and ivshmem-server has always complied. The device, however, accepts it out of order. If an interrupt setup arrived before it, though, it would be misinterpreted as connect notification. Fix the latent bug by relying on the spec and ivshmem-server's actual behavior. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-28-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Propagate errors through ivshmem_recv_setup()Markus Armbruster1-46/+83
This kills off the funny state described in the previous commit. Simplify ivshmem_io_read() accordingly, and update documentation. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1458066895-20632-27-git-send-email-armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2016-03-21ivshmem: Receive shared memory synchronously in realize()Markus Armbruster1-20/+48
When configured for interrupts (property "chardev" given), we receive the shared memory from an ivshmem server. We do so asynchronously after realize() completes, by setting up callbacks with qemu_chr_add_handlers(). Keeping server I/O out of realize() that way avoids delays due to a slow server. This is probably relevant only for hot plug. However, this funny "no shared memory, yet" state of the device also causes a raft of issues that are hard or impossible to work around: * The guest is exposed to this state: when we enter and leave it its shared memory contents is apruptly replaced, and device register IVPosition changes. This is a known issue. We document that guests should not access the shared memory after device initialization until the IVPosition register becomes non-negative. For cold plug, the funny state is unlikely to be visible in practice, because we normally receive the shared memory long before the guest gets around to mess with the device. For hot plug, the timing is tighter, but the relative slowness of PCI device configuration has a good chance to hide the funny state. In either case, guests complying with the documented procedure are safe. * Migration becomes racy. If migration completes before the shared memory setup completes on the source, shared memory contents is silently lost. Fortunately, migration is rather unlikely to win this race. If the shared memory's ramblock arrives at the destination before shared memory setup completes, migration fails. There is no known way for a management application to wait for shared memory setup to complete. All you can do is retry failed migration. You can improve your chances by leaving more time between running the destination QEMU and the migrate command. To mitigate silent memory loss, you need to ensure the server initializes shared memory exactly the same on source and destination. These issues are entirely undocumented so far. I'd expect the server to be almost always fast enough to hide these issues. But then rare catastrophic races are in a way the worst kind. This is way more trouble than I'm willing to take from any device. Kill the funny state by receiving shared memory synchronously in realize(). If your hot plug hangs, go kill your ivshmem server. For easier review, this commit only makes the receive synchronous, it doesn't add the necessary error propagation. Without that, the funny state persists. The next commit will do that, and kill it off for real. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-26-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Plug leaks on unplug, fix peer disconnectMarkus Armbruster1-12/+12
close_peer_eventfds() cleans up three things: ioeventfd triggers if they exist, eventfds, and the array to store them. Commit 98609cd (v1.2.0) fixed it not to clean up ioeventfd triggers when they don't exist (property ioeventfd=off, which is the default). Unfortunately, the fix also made it skip cleanup of the eventfds and the array then. This is a memory and file descriptor leak on unplug. Additionally, the reset of nb_eventfds is skipped. Doesn't matter on unplug. On peer disconnect, however, this permanently wedges the interrupt vectors used for that peer's ID. The eventfds stay behind, but aren't connected to a peer anymore. When the ID gets recycled for a new peer, the new peer's eventfds get assigned to vectors after the old ones. Commonly, the device's number of vectors matches the server's, so the new ones get dropped with a "Too many eventfd received" message. Interrupts either don't work (common case) or go to the wrong vector. Fix by narrowing the conditional to just the ioeventfd trigger cleanup. While there, move the "invalid" peer check to the only caller where it can actually happen, and tighten it to reject own ID. Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-25-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Disentangle ivshmem_read()Markus Armbruster1-79/+80
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-24-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Simplify rejection of invalid peer ID from serverMarkus Armbruster1-39/+22
ivshmem_read() processes server messages. These are 64 bit signed integers. -1 is shared memory setup, 16 bit unsigned is a peer ID, anything else is invalid. ivshmem_read() rejects invalid negative messages right away, silently. Invalid positive messages get rejected only in resize_peers(), and ivshmem_read() then prints the rather cryptic message "failed to resize peers array". Extend the first check to cover all invalid messages, make it report "server sent invalid message", and drop the second check. Now resize_peers() can't fail anymore; simplify. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-23-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Assert interrupts are set up onceMarkus Armbruster1-5/+2
An interrupt is set up when the interrupt's file descriptor is received. Each message applies to the next interrupt vector. Therefore, each vector cannot be set up more than once. ivshmem_add_kvm_msi_virq() half-heartedly tries not to rely on this by doing nothing then, but that's not going to recover from this error should it become possible in the future. watch_vector_notifier() doesn't even try. Simply assert what is the case, so we get alerted if we ever screw it up. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-22-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Leave INTx alone when using MSI-XMarkus Armbruster1-0/+9
The ivshmem device can either use MSI-X or legacy INTx for interrupts. With MSI-X enabled, peer interrupt events trigger an MSI as they should. But software can still raise INTx via interrupt status and mask register in BAR 0. This is explicitly prohibited by PCI Local Bus Specification Revision 3.0, section 6.8.3.3: While enabled for MSI or MSI-X operation, a function is prohibited from using its INTx# pin (if implemented) to request service (MSI, MSI-X, and INTx# are mutually exclusive). Fix the device model to leave INTx alone when using MSI-X. Document that we claim to use INTx in config space even when we don't. Unlike other devices, ivshmem does *not* use INTx when configured for MSI-X and MSI-X isn't enabled by software. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1458066895-20632-21-git-send-email-armbru@redhat.com>
2016-03-21ivshmem: Clean up MSI-X conditionsMarkus Armbruster1-12/+10
There are three predicates related to MSI-X: * ivshmem_has_feature(s, IVSHMEM_MSI) is true unless the non-MSI-X variant of the device is selected with msi=off. * msix_present() is true when the device has the PCI capability MSI-X. It's initially false, and becomes true during successful realize of the MSI-X variant of the device. Thus, it's the same as ivshmem_has_feature(s, IVSHMEM_MSI) for realized devices. * msix_enabled() is true when msix_present() is true and guest software has enabled MSI-X. Code that differs between the non-MSI-X and the MSI-X variant of the device needs to be guarded by ivshmem_has_feature(s, IVSHMEM_MSI) or by msix_present(), except the latter works only for realized devices. Code that depends on whether MSI-X is in use needs to be guarded with msix_enabled(). Code review led me to two minor messes: * ivshmem_vector_notify() calls msix_notify() even when !msix_enabled(), unlike most other MSI-X-capable devices. As far as I can tell, msix_notify() does nothing when !msix_enabled(). Add the guard anyway. * Most callers of ivshmem_use_msix() guard it with ivshmem_has_feature(s, IVSHMEM_MSI). Not necessary, because ivshmem_use_msix() does nothing when !msix_present(). That's ivshmem's only use of msix_present(), though. Guard it consistently, and drop the now redundant msix_present() check. While there, rename ivshmem_use_msix() to ivshmem_msix_vector_use(). Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1458066895-20632-20-git-send-email-armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
generated by cgit v1.1 at 2025-02-02 00:10:06 +0000