[libvirt] [RFC PATCHv4 13/15] qemu: consolidate migration to file code
Eric Blake
eblake at redhat.com
Thu Mar 10 02:18:31 UTC 2011
This points out that core dumps (still) don't work for root-squash
NFS, since the fd is not opened correctly. This patch should not
introduce any functionality change, it is just a refactoring to
avoid duplicated code.
* src/qemu/qemu_driver.c (qemuDomainMigrateToFile): New function.
(qemudDomainSaveFlag, doCoreDump): Use it.
---
src/qemu/qemu_driver.c | 249 +++++++++++++++++++++---------------------------
1 files changed, 110 insertions(+), 139 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 9de19ea..2422482 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -1766,6 +1766,101 @@ endjob:
return ret;
}
+/* Internal function called while driver lock is held and vm is active. */
+static int
+qemuDomainMigrateToFile(struct qemud_driver *driver, virDomainObjPtr vm,
+ virBitmapPtr qemuCaps,
+ int fd, off_t offset, const char *path,
+ int compressed,
+ bool is_reg, bool bypassSecurityDriver)
+{
+ qemuDomainObjPrivatePtr priv = vm->privateData;
+ virCgroupPtr cgroup = NULL;
+ int ret = -1;
+ int rc;
+
+ if (!is_reg &&
+ qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_DEVICES)) {
+ if (virCgroupForDomain(driver->cgroup, vm->def->name,
+ &cgroup, 0) != 0) {
+ qemuReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Unable to find cgroup for %s"),
+ vm->def->name);
+ goto cleanup;
+ }
+ rc = virCgroupAllowDevicePath(cgroup, path,
+ VIR_CGROUP_DEVICE_RW);
+ qemuAuditCgroupPath(vm, cgroup, "allow", path, "rw", rc);
+ if (rc < 0) {
+ virReportSystemError(-rc,
+ _("Unable to allow device %s for %s"),
+ path, vm->def->name);
+ goto cleanup;
+ }
+ }
+
+ if ((!bypassSecurityDriver) &&
+ virSecurityManagerSetSavedStateLabel(driver->securityManager,
+ vm, path) < 0)
+ goto cleanup;
+
+ if (compressed == QEMUD_SAVE_FORMAT_RAW) {
+ const char *args[] = { "cat", NULL };
+
+ qemuDomainObjEnterMonitorWithDriver(driver, vm);
+ if (qemuCaps && qemuCapsGet(qemuCaps, QEMU_CAPS_MIGRATE_QEMU_FD) &&
+ priv->monConfig->type == VIR_DOMAIN_CHR_TYPE_UNIX) {
+ rc = qemuMonitorMigrateToFd(priv->mon,
+ QEMU_MONITOR_MIGRATE_BACKGROUND,
+ fd);
+ } else {
+ rc = qemuMonitorMigrateToFile(priv->mon,
+ QEMU_MONITOR_MIGRATE_BACKGROUND,
+ args, path, offset);
+ }
+ qemuDomainObjExitMonitorWithDriver(driver, vm);
+ } else {
+ const char *prog = qemudSaveCompressionTypeToString(compressed);
+ const char *args[] = {
+ prog,
+ "-c",
+ NULL
+ };
+ qemuDomainObjEnterMonitorWithDriver(driver, vm);
+ rc = qemuMonitorMigrateToFile(priv->mon,
+ QEMU_MONITOR_MIGRATE_BACKGROUND,
+ args, path, offset);
+ qemuDomainObjExitMonitorWithDriver(driver, vm);
+ }
+
+ if (rc < 0)
+ goto cleanup;
+
+ rc = qemuMigrationWaitForCompletion(driver, vm);
+
+ if (rc < 0)
+ goto cleanup;
+
+ ret = 0;
+
+cleanup:
+ if ((!bypassSecurityDriver) &&
+ virSecurityManagerRestoreSavedStateLabel(driver->securityManager,
+ vm, path) < 0)
+ VIR_WARN("failed to restore save state label on %s", path);
+
+ if (cgroup != NULL) {
+ rc = virCgroupDenyDevicePath(cgroup, path,
+ VIR_CGROUP_DEVICE_RWM);
+ qemuAuditCgroupPath(vm, cgroup, "deny", path, "rwm", rc);
+ if (rc < 0)
+ VIR_WARN("Unable to deny device %s for %s %d",
+ path, vm->def->name, rc);
+ virCgroupFree(&cgroup);
+ }
+ return ret;
+}
+
/* This internal function expects the driver lock to already be held on
* entry and the vm must be active.
*/
@@ -1775,15 +1870,14 @@ static int qemudDomainSaveFlag(struct qemud_driver *driver, virDomainPtr dom,
{
char *xml = NULL;
struct qemud_save_header header;
- int bypassSecurityDriver = 0;
+ bool bypassSecurityDriver = false;
int ret = -1;
int rc;
virDomainEventPtr event = NULL;
qemuDomainObjPrivatePtr priv;
struct stat sb;
- int is_reg = 0;
+ bool is_reg = false;
unsigned long long offset;
- virCgroupPtr cgroup = NULL;
virBitmapPtr qemuCaps = NULL;
int fd = -1;
@@ -1838,9 +1932,9 @@ static int qemudDomainSaveFlag(struct qemud_driver *driver, virDomainPtr dom,
* that with NFS we can't actually stat() the file.
* The subsequent codepaths will still raise an error
* if a truely fatal problem is hit */
- is_reg = 1;
+ is_reg = true;
} else {
- is_reg = S_ISREG(sb.st_mode);
+ is_reg = !!S_ISREG(sb.st_mode);
}
offset = sizeof(header) + header.xml_len;
@@ -1935,7 +2029,7 @@ static int qemudDomainSaveFlag(struct qemud_driver *driver, virDomainPtr dom,
is NFS, we assume it's a root-squashing NFS share, and that
the security driver stuff would have failed anyway */
- bypassSecurityDriver = 1;
+ bypassSecurityDriver = true;
}
}
@@ -1945,86 +2039,13 @@ static int qemudDomainSaveFlag(struct qemud_driver *driver, virDomainPtr dom,
goto endjob;
}
- /* Allow qemu to access file */
-
- if (!is_reg &&
- qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_DEVICES)) {
- if (virCgroupForDomain(driver->cgroup, vm->def->name, &cgroup, 0) != 0) {
- qemuReportError(VIR_ERR_INTERNAL_ERROR,
- _("Unable to find cgroup for %s"),
- vm->def->name);
- goto endjob;
- }
- rc = virCgroupAllowDevicePath(cgroup, path,
- VIR_CGROUP_DEVICE_RW);
- qemuAuditCgroupPath(vm, cgroup, "allow", path, "rw", rc);
- if (rc < 0) {
- virReportSystemError(-rc,
- _("Unable to allow device %s for %s"),
- path, vm->def->name);
- goto endjob;
- }
- }
-
- if ((!bypassSecurityDriver) &&
- virSecurityManagerSetSavedStateLabel(driver->securityManager,
- vm, path) < 0)
- goto endjob;
-
- if (header.compressed == QEMUD_SAVE_FORMAT_RAW) {
- const char *args[] = { "cat", NULL };
-
- qemuDomainObjEnterMonitorWithDriver(driver, vm);
- if (qemuCapsGet(qemuCaps, QEMU_CAPS_MIGRATE_QEMU_FD) &&
- priv->monConfig->type == VIR_DOMAIN_CHR_TYPE_UNIX) {
- rc = qemuMonitorMigrateToFd(priv->mon,
- QEMU_MONITOR_MIGRATE_BACKGROUND,
- fd);
- } else {
- rc = qemuMonitorMigrateToFile(priv->mon,
- QEMU_MONITOR_MIGRATE_BACKGROUND,
- args, path, offset);
- }
- qemuDomainObjExitMonitorWithDriver(driver, vm);
- } else {
- const char *prog = qemudSaveCompressionTypeToString(header.compressed);
- const char *args[] = {
- prog,
- "-c",
- NULL
- };
- qemuDomainObjEnterMonitorWithDriver(driver, vm);
- rc = qemuMonitorMigrateToFile(priv->mon,
- QEMU_MONITOR_MIGRATE_BACKGROUND,
- args, path, offset);
- qemuDomainObjExitMonitorWithDriver(driver, vm);
- }
-
- if (rc < 0)
- goto endjob;
-
+ /* Perform the migration */
+ if (qemuDomainMigrateToFile(driver, vm, qemuCaps, fd, offset, path,
+ compressed, is_reg, bypassSecurityDriver) < 0)
+ goto cleanup;
if (VIR_CLOSE(fd) < 0) {
virReportSystemError(errno, _("unable to close %s"), path);
- goto endjob;
- }
-
- rc = qemuMigrationWaitForCompletion(driver, vm);
-
- if (rc < 0)
- goto endjob;
-
- if ((!bypassSecurityDriver) &&
- virSecurityManagerRestoreSavedStateLabel(driver->securityManager,
- vm, path) < 0)
- VIR_WARN("failed to restore save state label on %s", path);
-
- if (cgroup != NULL) {
- rc = virCgroupDenyDevicePath(cgroup, path,
- VIR_CGROUP_DEVICE_RWM);
- qemuAuditCgroupPath(vm, cgroup, "deny", path, "rwm", rc);
- if (rc < 0)
- VIR_WARN("Unable to deny device %s for %s %d",
- path, vm->def->name, rc);
+ goto cleanup;
}
ret = 0;
@@ -2050,22 +2071,7 @@ endjob:
if (rc < 0)
VIR_WARN0("Unable to resume guest CPUs after save failure");
}
-
- if (cgroup != NULL) {
- rc = virCgroupDenyDevicePath(cgroup, path,
- VIR_CGROUP_DEVICE_RWM);
- qemuAuditCgroupPath(vm, cgroup, "deny", path, "rwm", rc);
- if (rc < 0)
- VIR_WARN("Unable to deny device %s for %s: %d",
- path, vm->def->name, rc);
- }
-
- if ((!bypassSecurityDriver) &&
- virSecurityManagerRestoreSavedStateLabel(driver->securityManager,
- vm, path) < 0)
- VIR_WARN("failed to restore save state label on %s", path);
}
-
if (qemuDomainObjEndJob(vm) == 0)
vm = NULL;
}
@@ -2078,7 +2084,6 @@ cleanup:
unlink(path);
if (event)
qemuDomainEventQueue(driver, event);
- virCgroupFree(&cgroup);
return ret;
}
@@ -2282,9 +2287,6 @@ static int doCoreDump(struct qemud_driver *driver,
{
int fd = -1;
int ret = -1;
- qemuDomainObjPrivatePtr priv;
-
- priv = vm->privateData;
/* Create an empty file with appropriate ownership. */
if ((fd = open(path, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR)) < 0) {
@@ -2293,6 +2295,10 @@ static int doCoreDump(struct qemud_driver *driver,
goto cleanup;
}
+ if (qemuDomainMigrateToFile(driver, vm, NULL, fd, 0, path,
+ compress, true, false) < 0)
+ goto cleanup;
+
if (VIR_CLOSE(fd) < 0) {
virReportSystemError(errno,
_("unable to save file %s"),
@@ -2300,42 +2306,7 @@ static int doCoreDump(struct qemud_driver *driver,
goto cleanup;
}
- if (virSecurityManagerSetSavedStateLabel(driver->securityManager,
- vm, path) < 0)
- goto cleanup;
-
- qemuDomainObjEnterMonitorWithDriver(driver, vm);
- if (compress == QEMUD_SAVE_FORMAT_RAW) {
- const char *args[] = {
- "cat",
- NULL,
- };
- ret = qemuMonitorMigrateToFile(priv->mon,
- QEMU_MONITOR_MIGRATE_BACKGROUND,
- args, path, 0);
- } else {
- const char *prog = qemudSaveCompressionTypeToString(compress);
- const char *args[] = {
- prog,
- "-c",
- NULL,
- };
- ret = qemuMonitorMigrateToFile(priv->mon,
- QEMU_MONITOR_MIGRATE_BACKGROUND,
- args, path, 0);
- }
- qemuDomainObjExitMonitorWithDriver(driver, vm);
- if (ret < 0)
- goto cleanup;
-
- ret = qemuMigrationWaitForCompletion(driver, vm);
-
- if (ret < 0)
- goto cleanup;
-
- if (virSecurityManagerRestoreSavedStateLabel(driver->securityManager,
- vm, path) < 0)
- goto cleanup;
+ ret = 0;
cleanup:
if (ret != 0)
--
1.7.4
More information about the libvir-list
mailing list