[libvirt] [PATCH v3 16/18] blockcopy: add qemu implementation of new API

[Eric Blake]

The hard part of managing the disk copy is already coded; all
this had to do was convert the XML and virTypedParameters into
the internal representation.

With this patch, all blockcopy operations that used the old
API should also work via the new API.  Additional extensions,
such as supporting the granularity tunable or a network rather
than file destination, will be added as later patches.

* src/qemu/qemu_driver.c (qemuDomainBlockCopy): New function.

Signed-off-by: Eric Blake <eblake at redhat.com>
---
 src/qemu/qemu_driver.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 85 insertions(+)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index d3f1042..d93e184 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -15611,6 +15611,90 @@ qemuDomainBlockRebase(virDomainPtr dom, const char *path, const char *base,
     return ret;
 }

+
+static int
+qemuDomainBlockCopy(virDomainPtr dom, const char *disk, const char *destxml,
+                    virTypedParameterPtr params, int nparams,
+                    unsigned int flags)
+{
+    virQEMUDriverPtr driver = dom->conn->privateData;
+    virDomainObjPtr vm;
+    int ret = -1;
+    unsigned long long bandwidth = 0;
+    unsigned int granularity = 0;
+    unsigned long long buf_size = 0;
+    virStorageSourcePtr dest = NULL;
+    size_t i;
+
+    virCheckFlags(VIR_DOMAIN_BLOCK_COPY_SHALLOW |
+                  VIR_DOMAIN_BLOCK_COPY_REUSE_EXT, -1);
+    if (virTypedParamsValidate(params, nparams,
+                               VIR_DOMAIN_BLOCK_COPY_BANDWIDTH,
+                               VIR_TYPED_PARAM_ULLONG,
+                               VIR_DOMAIN_BLOCK_COPY_GRANULARITY,
+                               VIR_TYPED_PARAM_UINT,
+                               VIR_DOMAIN_BLOCK_COPY_BUF_SIZE,
+                               VIR_TYPED_PARAM_ULLONG,
+                               NULL) < 0)
+        return -1;
+
+    if (!(vm = qemuDomObjFromDomain(dom)))
+        return -1;
+
+    if (virDomainBlockCopyEnsureACL(dom->conn, vm->def) < 0)
+        goto cleanup;
+
+    for (i = 0; i < nparams; i++) {
+        virTypedParameterPtr param = &params[i];
+
+        /* Typed params (wisely) refused to expose unsigned long, but
+         * back-compat demands that we stick with a maximum of
+         * unsigned long bandwidth in MiB/s, while our value is
+         * unsigned long long in bytes/s.  Hence, we have to do
+         * overflow detection if this is a 32-bit server handling a
+         * 64-bit client.  */
+        if (STREQ(param->field, VIR_DOMAIN_BLOCK_COPY_BANDWIDTH)) {
+            if (sizeof(unsigned long) < sizeof(bandwidth) &&
+                param->value.ul > ULONG_MAX * (1ULL << 20)) {
+                virReportError(VIR_ERR_OVERFLOW,
+                               _("bandwidth must be less than %llu bytes"),
+                               ULONG_MAX * (1ULL << 20));
+                goto cleanup;
+            }
+            bandwidth = param->value.ul;
+        } else if (STREQ(param->field, VIR_DOMAIN_BLOCK_COPY_GRANULARITY)) {
+            granularity = param->value.ui;
+        } else if (STREQ(param->field, VIR_DOMAIN_BLOCK_COPY_BUF_SIZE)) {
+            buf_size = param->value.ul;
+        }
+    }
+    if (granularity) {
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                       _("granularity tuning not supported yet"));
+        goto cleanup;
+    }
+    if (buf_size) {
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                       _("buffer size tuning not supported yet"));
+        goto cleanup;
+    }
+
+    if (!(dest = virDomainDiskDefSourceParse(destxml, vm->def, driver->xmlopt,
+                                             VIR_DOMAIN_XML_INACTIVE)))
+        goto cleanup;
+
+    ret = qemuDomainBlockCopyCommon(vm, dom->conn, disk, dest,
+                                    bandwidth, flags);
+    vm = NULL;
+
+ cleanup:
+    virStorageSourceFree(dest);
+    if (vm)
+        virObjectUnlock(vm);
+    return ret;
+}
+
+
 static int
 qemuDomainBlockPull(virDomainPtr dom, const char *path, unsigned long bandwidth,
                     unsigned int flags)
@@ -17683,6 +17767,7 @@ static virDriver qemuDriver = {
     .domainBlockJobSetSpeed = qemuDomainBlockJobSetSpeed, /* 0.9.4 */
     .domainBlockPull = qemuDomainBlockPull, /* 0.9.4 */
     .domainBlockRebase = qemuDomainBlockRebase, /* 0.9.10 */
+    .domainBlockCopy = qemuDomainBlockCopy, /* 1.2.8 */
     .domainBlockCommit = qemuDomainBlockCommit, /* 1.0.0 */
     .connectIsAlive = qemuConnectIsAlive, /* 0.9.8 */
     .nodeSuspendForDuration = qemuNodeSuspendForDuration, /* 0.9.8 */
-- 
1.9.3