From 29271efbf03fa88b54090dca46c42304a28c2fc3 Mon Sep 17 00:00:00 2001

Message-Id: <29271efbf03fa88b54090dca46c42304a28c2fc3.1377873637.git.jdenemar@redhat.com>

From: Guannan Ren <gren@redhat.com>

Date: Thu, 8 Aug 2013 16:07:27 +0800

Subject: [PATCH] qemu: add helper functions for diskchain checking

Resovles: https://bugzilla.redhat.com/show_bug.cgi?id=910171

(cherry picked from commit d7b7aa2c206951bef3b1bfece656394d1775cb7d)

*src/util/virstoragefile.c: Add a helper function to get

the first name of missing backing files, if the name is NULL,

it means the diskchain is not broken.

*src/qemu/qemu_domain.c: qemuDiskChainCheckBroken(disk) to

check if its chain is broken

---

 src/libvirt_private.syms  |  1 +

 src/qemu/qemu_domain.c    | 22 ++++++++++++++++++++++

 src/qemu/qemu_domain.h    |  3 +++

 src/util/virstoragefile.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++

 src/util/virstoragefile.h |  2 ++

 5 files changed, 74 insertions(+)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms

index 0247a46..9cfb84c 100644

--- a/src/libvirt_private.syms

+++ b/src/libvirt_private.syms

@@ -1882,6 +1882,7 @@ virSocketAddrSetPort;

 # util/virstoragefile.h

+virStorageFileChainGetBroken;

 virStorageFileChainLookup;

 virStorageFileFeatureTypeFromString;

 virStorageFileFeatureTypeToString;

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c

index 13303da..fd62deb 100644

--- a/src/qemu/qemu_domain.c

+++ b/src/qemu/qemu_domain.c

@@ -2228,6 +2228,28 @@ qemuDomainCleanupRun(virQEMUDriverPtr driver,

 }

 int

+qemuDiskChainCheckBroken(virDomainDiskDefPtr disk)

+{

+    char *brokenFile = NULL;

+

+    if (!disk->src || !disk->backingChain)

+        return 0;

+

+    if (virStorageFileChainGetBroken(disk->backingChain, &brokenFile) < 0)

+        return -1;

+

+    if (brokenFile) {

+        virReportError(VIR_ERR_INVALID_ARG,

+                       _("Backing file '%s' of image '%s' is missing."),

+                       brokenFile, disk->src);

+        VIR_FREE(brokenFile);

+        return -1;

+    }

+

+    return 0;

+}

+

+int

 qemuDomainDetermineDiskChain(virQEMUDriverPtr driver,

                              virDomainDiskDefPtr disk,

                              bool force)

diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h

index 9a959d6..0a4a51e 100644

--- a/src/qemu/qemu_domain.h

+++ b/src/qemu/qemu_domain.h

@@ -347,6 +347,9 @@ bool qemuDomainJobAllowed(qemuDomainObjPrivatePtr priv,

 int qemuDomainCheckDiskPresence(virQEMUDriverPtr driver,

                                 virDomainObjPtr vm,

                                 bool start_with_state);

+

+int qemuDiskChainCheckBroken(virDomainDiskDefPtr disk);

+

 int qemuDomainDetermineDiskChain(virQEMUDriverPtr driver,

                                  virDomainDiskDefPtr disk,

                                  bool force);

diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c

index cb6df91..0b9cec3 100644

--- a/src/util/virstoragefile.c

+++ b/src/util/virstoragefile.c

@@ -572,6 +572,13 @@ virFindBackingFile(const char *start, bool start_is_dir, const char *path,

         goto cleanup;

     }

+    if (virFileAccessibleAs(combined, F_OK, getuid(), getgid()) < 0) {

+        virReportSystemError(errno,

+                             _("Cannot access backing file '%s'"),

+                             combined);

+        goto cleanup;

+    }

+

     if (!(*canonical = canonicalize_file_name(combined))) {

         virReportSystemError(errno,

                              _("Can't canonicalize path '%s'"), path);

@@ -1097,6 +1104,45 @@ virStorageFileGetMetadata(const char *path, int format,

 }

 /**

+ * virStorageFileChainCheckBroken

+ *

+ * If CHAIN is broken, set *brokenFile to the broken file name,

+ * otherwise set it to NULL. Caller MUST free *brokenFile after use.

+ * Return 0 on success, negative on error.

+ */

+int

+virStorageFileChainGetBroken(virStorageFileMetadataPtr chain,

+                             char **brokenFile)

+{

+    virStorageFileMetadataPtr tmp;

+    int ret = -1;

+

+    if (!chain)

+        return 0;

+

+    *brokenFile = NULL;

+

+    tmp = chain;

+    while (tmp) {

+        /* Break if no backing store or backing store is not file */

+       if (!tmp->backingStoreRaw)

+           break;

+       if (!tmp->backingStore) {

+           if (VIR_STRDUP(*brokenFile, tmp->backingStoreRaw) < 0)

+               goto error;

+           break;

+       }

+       tmp = tmp->backingMeta;

+    }

+

+    ret = 0;

+

+error:

+    return ret;

+}

+

+

+/**

  * virStorageFileFreeMetadata:

  *

  * Free pointers in passed structure and structure itself.

diff --git a/src/util/virstoragefile.h b/src/util/virstoragefile.h

index 4cb47e6..1f89839 100644

--- a/src/util/virstoragefile.h

+++ b/src/util/virstoragefile.h

@@ -90,6 +90,8 @@ virStorageFileMetadataPtr virStorageFileGetMetadata(const char *path,

 virStorageFileMetadataPtr virStorageFileGetMetadataFromFD(const char *path,

                                                           int fd,

                                                           int format);

+int virStorageFileChainGetBroken(virStorageFileMetadataPtr chain,

+                                 char **broken_file);

 const char *virStorageFileChainLookup(virStorageFileMetadataPtr chain,

                                       const char *start,

-- 

1.8.3.2