File libvirt-storageVolCreateXMLFrom-Allow-multiple-accesses-to-origvol.patch of Package libvirt

From b84933c85040aa69fc14d0a1fcd89539c4078531 Mon Sep 17 00:00:00 2001
Message-Id: <b84933c85040aa69fc14d0a1fcd89539c4078531@dist-git>
From: Michal Privoznik <mprivozn@redhat.com>
Date: Tue, 6 May 2014 13:41:25 +0200
Subject: [PATCH] storageVolCreateXMLFrom: Allow multiple accesses to origvol

https://bugzilla.redhat.com/show_bug.cgi?id=1058700

When creating a new volume, it is possible to copy data into it from
another already existing volume (referred to as @origvol). Obviously,
the read-only access to @origvol is required, which is thread safe
(probably not performance-wise though). However, with current code
both @newvol and @origvol are marked as building for the time of
copying data from the @origvol to @newvol. The rationale behind
is to disallow some operations on both @origvol and @newvol, e.g.
vol-wipe, vol-delete, vol-download. While it makes sense to not allow
such operations on partly copied mirror, but it doesn't make sense to
disallow vol-create or vol-download on the source (@origvol).

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit eb54426659888bf04fdef409afaccf8c0fd199a0)

Conflicts:
	src/storage/storage_driver.c: Context, as ACLs are not backported
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/conf/storage_conf.h      |  1 +
 src/storage/storage_driver.c | 32 ++++++++++++++++++++++++++++++--
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/src/conf/storage_conf.h b/src/conf/storage_conf.h
index 743b768..977c34a 100644
--- a/src/conf/storage_conf.h
+++ b/src/conf/storage_conf.h
@@ -104,6 +104,7 @@ struct _virStorageVolDef {
     int type; /* virStorageVolType enum */
 
     unsigned int building;
+    unsigned int in_use;
 
     unsigned long long allocation; /* bytes */
     unsigned long long capacity; /* bytes */
diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
index 5f5e86c..1b3c9f5 100644
--- a/src/storage/storage_driver.c
+++ b/src/storage/storage_driver.c
@@ -1448,6 +1448,13 @@ storageVolumeDelete(virStorageVolPtr obj,
         goto cleanup;
     }
 
+    if (vol->in_use) {
+        virReportError(VIR_ERR_OPERATION_INVALID,
+                       _("volume '%s' is still in use."),
+                       vol->name);
+        goto cleanup;
+    }
+
     if (vol->building) {
         virReportError(VIR_ERR_OPERATION_INVALID,
                        _("volume '%s' is still being allocated."),
@@ -1708,8 +1715,8 @@ storageVolumeCreateXMLFrom(virStoragePoolPtr obj,
 
     /* Drop the pool lock during volume allocation */
     pool->asyncjobs++;
-    origvol->building = 1;
     newvol->building = 1;
+    origvol->in_use++;
     virStoragePoolObjUnlock(pool);
 
     if (origpool) {
@@ -1725,7 +1732,7 @@ storageVolumeCreateXMLFrom(virStoragePoolPtr obj,
         virStoragePoolObjLock(origpool);
     storageDriverUnlock(driver);
 
-    origvol->building = 0;
+    origvol->in_use--;
     newvol->building = 0;
     allocation = newvol->allocation;
     pool->asyncjobs--;
@@ -1864,6 +1871,13 @@ storageVolumeUpload(virStorageVolPtr obj,
         goto out;
     }
 
+    if (vol->in_use) {
+        virReportError(VIR_ERR_OPERATION_INVALID,
+                       _("volume '%s' is still in use."),
+                       vol->name);
+        goto out;
+    }
+
     if (vol->building) {
         virReportError(VIR_ERR_OPERATION_INVALID,
                        _("volume '%s' is still being allocated."),
@@ -1930,6 +1944,13 @@ storageVolumeResize(virStorageVolPtr obj,
         goto out;
     }
 
+    if (vol->in_use) {
+        virReportError(VIR_ERR_OPERATION_INVALID,
+                       _("volume '%s' is still in use."),
+                       vol->name);
+        goto out;
+    }
+
     if (vol->building) {
         virReportError(VIR_ERR_OPERATION_INVALID,
                        _("volume '%s' is still being allocated."),
@@ -2226,6 +2247,13 @@ storageVolumeWipePattern(virStorageVolPtr obj,
         goto out;
     }
 
+    if (vol->in_use) {
+        virReportError(VIR_ERR_OPERATION_INVALID,
+                       _("volume '%s' is still in use."),
+                       vol->name);
+        goto out;
+    }
+
     if (vol->building) {
         virReportError(VIR_ERR_OPERATION_INVALID,
                        _("volume '%s' is still being allocated."),
-- 
1.9.2