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* docs: Stop building qemu-docPeter Maydell2020-03-061-2/+2
| | | | | | | | | | Stop building the old texinfo qemu-doc; all its contents are now available in the Sphinx-generated manuals and manpages. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Tested-by: Alex Bennée <alex.bennee@linaro.org> Message-id: 20200228153619.9906-32-peter.maydell@linaro.org
* hw/misc/ivshmem: Remove deprecated "ivshmem" legacy deviceThomas Huth2019-01-151-2/+6
| | | | | | | | | | | | | | | It's been marked as deprecated in QEMU v2.6.0 already, so really nobody should use the legacy "ivshmem" device anymore (but use ivshmem-plain or ivshmem-doorbell instead). Time to remove the deprecated device now. Belatedly also update a mention of the deprecated "ivshmem" in the file docs/specs/ivshmem-spec.txt to "ivshmem-doorbell". Missed in commit 5400c02b90b ("ivshmem: Split ivshmem-plain, ivshmem-doorbell off ivshmem"). Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* ivshmem: Require master to have ID zeroMarkus Armbruster2016-03-211-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ivshmem: Split ivshmem-plain, ivshmem-doorbell off ivshmemMarkus Armbruster2016-03-211-31/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ivshmem: Propagate errors through ivshmem_recv_setup()Markus Armbruster2016-03-211-9/+11
| | | | | | | | | | 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>
* ivshmem: Don't destroy the chardev on version mismatchMarkus Armbruster2016-03-211-0/+3
| | | | | | | | | | | | | | | Yes, the chardev is commonly useless after we read a bad version from it, but destroying it is inappropriate anyway: the user created it, so the user should be able to hold on to it as long as he likes. We don't destroy it on other errors. Screwed up in commit 5105b1d. Stop reading instead. Also note QEMU's behavior in ivshmem-spec.txt. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-16-git-send-email-armbru@redhat.com>
* ivshmem: Rewrite specification documentMarkus Armbruster2016-03-211-0/+243
This started as an attempt to update ivshmem_device_spec.txt for clarity, accuracy and completeness while working on its code, and quickly became a full rewrite. Since the diff would be useless anyway, I'm using the opportunity to rename the file to ivshmem-spec.txt. I tried hard to ensure the new text contradicts neither the old text nor the code. If the new text contradicts the old text but not the code, it's probably a bug in the old text. If the new text contradicts both, its probably a bug in the new text. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1458066895-20632-11-git-send-email-armbru@redhat.com>