[libvirt] [PATCH 3/3] qemu: caps: Add capability for dynamic 'auto-read-only' support for files

Initial implementation of 'auto-read-only' didn't reopen the backing files when needed. For '-blockdev' to work we need to be able to tel qemu to open a file read-only and change it during blockjobs as we label backing chains with a sVirt label which does not allow writing. The dynamic auto-read-only supports this as it reopens files when writing is demanded. Add a capability to detect that the posix file based backends support the dynamic part. --- src/qemu/qemu_capabilities.c | 2 ++ src/qemu/qemu_capabilities.h | 1 + tests/qemucapabilitiesdata/caps_4.1.0.x86_64.xml | 1 + 3 files changed, 4 insertions(+) diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index d0fdd1da9f..4e6d71f525 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -530,6 +530,7 @@ VIR_ENUM_IMPL(virQEMUCaps, /* 330 */ "bitmap-merge", "nbd-bitmap", + "blockdev-file-dynamic-auto-read-only", ); @@ -1270,6 +1271,7 @@ static struct virQEMUCapsStringFlags virQEMUCapsQMPSchemaQueries[] = { { "query-iothreads/ret-type/poll-max-ns", QEMU_CAPS_IOTHREAD_POLLING }, { "query-display-options/ret-type/+egl-headless/rendernode", QEMU_CAPS_EGL_HEADLESS_RENDERNODE }, { "nbd-server-add/arg-type/bitmap", QEMU_CAPS_NBD_BITMAP }, + { "blockdev-add/arg-type/+file/$dynamic-auto-read-only", QEMU_CAPS_BLOCK_FILE_AUTO_READONLY_DYNAMIC }, }; typedef struct _virQEMUCapsObjectTypeProps virQEMUCapsObjectTypeProps; diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h index 3032d4edcd..399a30dc4c 100644 --- a/src/qemu/qemu_capabilities.h +++ b/src/qemu/qemu_capabilities.h @@ -512,6 +512,7 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */ /* 330 */ QEMU_CAPS_BITMAP_MERGE, /* block-dirty-bitmap-merge */ QEMU_CAPS_NBD_BITMAP, /* nbd-server-add supports bitmap */ + QEMU_CAPS_BLOCK_FILE_AUTO_READONLY_DYNAMIC, /* the auto-read-only property of block backends for files is dynamic */ QEMU_CAPS_LAST /* this must always be the last item */ } virQEMUCapsFlags; diff --git a/tests/qemucapabilitiesdata/caps_4.1.0.x86_64.xml b/tests/qemucapabilitiesdata/caps_4.1.0.x86_64.xml index a22b050620..b01b57d3b1 100644 --- a/tests/qemucapabilitiesdata/caps_4.1.0.x86_64.xml +++ b/tests/qemucapabilitiesdata/caps_4.1.0.x86_64.xml @@ -204,6 +204,7 @@ <flag name='query-current-machine'/> <flag name='bitmap-merge'/> <flag name='nbd-bitmap'/> + <flag name='blockdev-file-dynamic-auto-read-only'/> <version>4000050</version> <kvmVersion>0</kvmVersion> <microcodeVersion>43100759</microcodeVersion> -- 2.21.0