On 12/14/2012 08:44 AM, Osier Yang wrote:
This prevents the domain starting if the shared disk's setting
conflicts with other active domain(s), E.g. A domain with
"cdbfilter" set as "yes", however, another active domain is using
it set as "no".
---
src/qemu/qemu_process.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++
src/qemu/qemu_process.h | 2 +
2 files changed, 53 insertions(+), 0 deletions(-)
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index bcea0ff..1e2baac 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -3385,6 +3385,54 @@ qemuProcessReconnectAll(virConnectPtr conn, virQEMUDriverPtr
driver)
virHashForEach(driver->domains.objs, qemuProcessReconnectHelper, &data);
}
+/* Check if a shared disk's setting conflicts with the conf
+ * used by other domain(s). Currently only checks the cdbfilter
+ * setting.
Probably worth documenting that this function should only be called on
disks with a block device source...
+ *
+ * Returns 0 if no conflicts, otherwise returns -1.
+ */
+int
+qemuCheckSharedDisk(virHashTablePtr sharedDisks,
+ virDomainDiskDefPtr disk)
+{
+ int val;
+ size_t *ref = NULL;
+ char *key = NULL;
+ int ret = 0;
+
+ if (!(key = qemuGetSharedDiskKey(disk->src)))
+ return -1;
since you error out on regular files. (You correctly obey that
restriction for now, but without documentation, it might be possible to
reuse this function from the wrong context in a future patch.)
+
+ /* It can't be conflict if no other domain is
+ * is sharing it.
+ */
+ if (!(ref = virHashLookup(sharedDisks, key)))
+ goto cleanup;
+
+ if (ref == (void *)0x1)
+ goto cleanup;
+
+ if (virGetDeviceUnprivSGIO(disk->src, NULL, &val) < 0) {
+ ret = -1;
+ goto cleanup;
+ }
+
+ if ((val == 0 &&
+ disk->cdbfilter == VIR_DOMAIN_DISK_CDB_FILTER_YES) ||
Does this do the right thing if disk->cdbfilter ==
VIR_DOMAIN_DISK_CDB_FILTER_DEFAULT (that is, the user didn't specify the
cdbfilter attribute)? Again, this area of code may need tweaks if you
take my suggestion of making rawio a three-value enum.
+ (val == 1 &&
+ disk->cdbfilter == VIR_DOMAIN_DISK_CDB_FILTER_NO))
+ goto cleanup;
+
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("cdbfilter of shared disk '%s' conflicts with other
"
+ "active domains"), disk->src);
INTERNAL_ERROR is wrong. I think VIR_ERR_OPERATION_INVALID fits better.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library
http://libvirt.org