[libvirt] [PATCH v2 4/7] lockd_driver_lockd: Implement metadata flag

[Michal Privoznik]

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/locking/lock_daemon_dispatch.c | 12 ++++++++++--
 src/locking/lock_driver_lockd.c    | 31 +++++++++++++++++++++----------
 src/locking/lock_driver_lockd.h    |  1 +
 3 files changed, 32 insertions(+), 12 deletions(-)

diff --git a/src/locking/lock_daemon_dispatch.c b/src/locking/lock_daemon_dispatch.c
index 10248ec0b5..c24571ceac 100644
--- a/src/locking/lock_daemon_dispatch.c
+++ b/src/locking/lock_daemon_dispatch.c
@@ -37,6 +37,9 @@ VIR_LOG_INIT("locking.lock_daemon_dispatch");
 
 #include "lock_daemon_dispatch_stubs.h"
 
+#define DEFAULT_OFFSET 0
+#define METADATA_OFFSET 1
+
 static int
 virLockSpaceProtocolDispatchAcquireResource(virNetServerPtr server ATTRIBUTE_UNUSED,
                                             virNetServerClientPtr client,
@@ -50,13 +53,14 @@ virLockSpaceProtocolDispatchAcquireResource(virNetServerPtr server ATTRIBUTE_UNU
         virNetServerClientGetPrivateData(client);
     virLockSpacePtr lockspace;
     unsigned int newFlags;
-    off_t start = 0;
+    off_t start = DEFAULT_OFFSET;
     off_t len = 1;
 
     virMutexLock(&priv->lock);
 
     virCheckFlagsGoto(VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_SHARED |
-                      VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_AUTOCREATE, cleanup);
+                      VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_AUTOCREATE |
+                      VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_METADATA, cleanup);
 
     if (priv->restricted) {
         virReportError(VIR_ERR_OPERATION_DENIED, "%s",
@@ -82,6 +86,10 @@ virLockSpaceProtocolDispatchAcquireResource(virNetServerPtr server ATTRIBUTE_UNU
         newFlags |= VIR_LOCK_SPACE_ACQUIRE_SHARED;
     if (flags & VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_AUTOCREATE)
         newFlags |= VIR_LOCK_SPACE_ACQUIRE_AUTOCREATE;
+    if (flags & VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_METADATA) {
+        start = METADATA_OFFSET;
+        newFlags |= VIR_LOCK_SPACE_ACQUIRE_WAIT;
+    }
 
     if (virLockSpaceAcquireResource(lockspace,
                                     args->name,
diff --git a/src/locking/lock_driver_lockd.c b/src/locking/lock_driver_lockd.c
index 957a963a7b..bd14ed8930 100644
--- a/src/locking/lock_driver_lockd.c
+++ b/src/locking/lock_driver_lockd.c
@@ -475,9 +475,11 @@ static int virLockManagerLockDaemonAddResource(virLockManagerPtr lock,
     bool autoCreate = false;
 
     virCheckFlags(VIR_LOCK_MANAGER_RESOURCE_READONLY |
-                  VIR_LOCK_MANAGER_RESOURCE_SHARED, -1);
+                  VIR_LOCK_MANAGER_RESOURCE_SHARED |
+                  VIR_LOCK_MANAGER_RESOURCE_METADATA, -1);
 
-    if (flags & VIR_LOCK_MANAGER_RESOURCE_READONLY)
+    if (flags & VIR_LOCK_MANAGER_RESOURCE_READONLY &&
+        !(flags & VIR_LOCK_MANAGER_RESOURCE_METADATA))
         return 0;
 
     switch (type) {
@@ -489,7 +491,8 @@ static int virLockManagerLockDaemonAddResource(virLockManagerPtr lock,
         }
         if (!driver->autoDiskLease) {
             if (!(flags & (VIR_LOCK_MANAGER_RESOURCE_SHARED |
-                           VIR_LOCK_MANAGER_RESOURCE_READONLY)))
+                           VIR_LOCK_MANAGER_RESOURCE_READONLY |
+                           VIR_LOCK_MANAGER_RESOURCE_METADATA)))
                 priv->hasRWDisks = true;
             return 0;
         }
@@ -602,6 +605,10 @@ static int virLockManagerLockDaemonAddResource(virLockManagerPtr lock,
         priv->resources[priv->nresources-1].flags |=
             VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_AUTOCREATE;
 
+    if (flags & VIR_LOCK_MANAGER_RESOURCE_METADATA)
+        priv->resources[priv->nresources-1].flags |=
+            VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_METADATA;
+
     return 0;
 
  error:
@@ -626,12 +633,15 @@ static int virLockManagerLockDaemonAcquire(virLockManagerPtr lock,
     virCheckFlags(VIR_LOCK_MANAGER_ACQUIRE_REGISTER_ONLY |
                   VIR_LOCK_MANAGER_ACQUIRE_RESTRICT, -1);
 
-    if (priv->nresources == 0 &&
-        priv->hasRWDisks &&
-        driver->requireLeaseForDisks) {
-        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
-                       _("Read/write, exclusive access, disks were present, but no leases specified"));
-        return -1;
+    if (priv->nresources == 0) {
+        if (priv->hasRWDisks &&
+            driver->requireLeaseForDisks) {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                           _("Read/write, exclusive access, disks were present, but no leases specified"));
+            return -1;
+        }
+
+        return 0;
     }
 
     if (!(client = virLockManagerLockDaemonConnect(lock, &program, &counter)))
@@ -711,7 +721,8 @@ static int virLockManagerLockDaemonRelease(virLockManagerPtr lock,
 
         args.flags &=
             ~(VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_SHARED |
-              VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_AUTOCREATE);
+              VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_AUTOCREATE |
+              VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_METADATA);
 
         if (virNetClientProgramCall(program,
                                     client,
diff --git a/src/locking/lock_driver_lockd.h b/src/locking/lock_driver_lockd.h
index 6931fe7425..9882793260 100644
--- a/src/locking/lock_driver_lockd.h
+++ b/src/locking/lock_driver_lockd.h
@@ -25,6 +25,7 @@
 enum virLockSpaceProtocolAcquireResourceFlags {
         VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_SHARED = (1 << 0),
         VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_RESOURCE_AUTOCREATE = (1 << 1),
+        VIR_LOCK_SPACE_PROTOCOL_ACQUIRE_METADATA = (1 << 2),
 };
 
 #endif /* __VIR_LOCK_DRIVER_LOCKD_H__ */
-- 
2.16.4