3:47 p.m.
Use the virStorageFileGetUniqueIdentifier() function to get a unique
identifier regardless of the target storage type instead of relying on
canonicalize_path().
A new function that checks wether we support a given image is introduced
to avoid errors for unimplemented backends.
---
src/storage/storage_driver.c | 77 +++++++++++++++++++++++++++++++-------------
1 file changed, 54 insertions(+), 23 deletions(-)
diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
index cd4c6b5..eebb7ee 100644
--- a/src/storage/storage_driver.c
+++ b/src/storage/storage_driver.c
@@ -2788,6 +2788,30 @@ virStorageFileIsInitialized(virStorageSourcePtr src)
return !!src->drv;
}
+
+static bool
+virStorageFileSupportsBackingChainTraversal(virStorageSourcePtr src)
+{
+ int actualType = virStorageSourceGetActualType(src);
+ virStorageFileBackendPtr backend;
+
+ if (!src)
+ return false;
+
+ if (src->drv) {
+ backend = src->drv->backend;
+ } else {
+ if (!(backend = virStorageFileBackendForTypeInternal(actualType,
+ src->protocol,
+ false)))
+ return false;
+ }
+
+ return backend->storageFileGetUniqueIdentifier &&
+ backend->storageFileReadHeader &&
+ backend->storageFileAccess;
+}
+
void
virStorageFileDeinit(virStorageSourcePtr src)
{
@@ -3104,7 +3128,6 @@ virFindBackingFile(const char *start, const char *path,
/* Recursive workhorse for virStorageFileGetMetadata. */
static int
virStorageFileGetMetadataRecurse(virStorageSourcePtr src,
- const char *canonPath,
uid_t uid, gid_t gid,
bool allow_probe,
virHashTablePtr cycle)
@@ -3112,49 +3135,63 @@ virStorageFileGetMetadataRecurse(virStorageSourcePtr src,
int fd;
int ret = -1;
struct stat st;
+ const char *uniqueName;
virStorageSourcePtr backingStore = NULL;
int backingFormat;
- VIR_DEBUG("path=%s canonPath=%s dir=%s format=%d uid=%d gid=%d probe=%d",
- src->path, canonPath, NULLSTR(src->relDir), src->format,
+ VIR_DEBUG("path=%s dir=%s format=%d uid=%d gid=%d probe=%d",
+ src->path, NULLSTR(src->relDir), src->format,
(int)uid, (int)gid, allow_probe);
- if (virHashLookup(cycle, canonPath)) {
- virReportError(VIR_ERR_INTERNAL_ERROR,
- _("backing store for %s is self-referential"),
- src->path);
+ /* exit if we can't load information about the current image */
+ if (!virStorageFileSupportsBackingChainTraversal(src))
+ return 0;
+
+ if (virStorageFileInitAs(src, uid, gid) < 0)
return -1;
+
+ if (!(uniqueName = virStorageFileGetUniqueIdentifier(src)))
+ goto cleanup;
+
+ if (virHashLookup(cycle, uniqueName)) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("backing store for %s (%s) is self-referential"),
+ src->path, uniqueName);
+ goto cleanup;
}
- if (virHashAddEntry(cycle, canonPath, (void *)1) < 0)
- return -1;
+ if (virHashAddEntry(cycle, uniqueName, (void *)1) < 0)
+ goto cleanup;
if (virStorageSourceGetActualType(src) != VIR_STORAGE_TYPE_NETWORK) {
if ((fd = virFileOpenAs(src->path, O_RDONLY, 0, uid, gid, 0)) < 0) {
virReportSystemError(-fd, _("Failed to open file '%s'"),
src->path);
- return -1;
+ goto cleanup;
}
if (virStorageFileGetMetadataFromFDInternal(src, fd,
&backingFormat) < 0) {
VIR_FORCE_CLOSE(fd);
- return -1;
+ goto cleanup;
}
if (VIR_CLOSE(fd) < 0)
VIR_WARN("could not close file %s", src->path);
} else {
/* TODO: currently we call this only for local storage */
- return 0;
+ ret = 0;
+ goto cleanup;
}
/* check whether we need to go deeper */
- if (!src->backingStoreRaw)
- return 0;
+ if (!src->backingStoreRaw) {
+ ret = 0;
+ goto cleanup;
+ }
if (VIR_ALLOC(backingStore) < 0)
- return -1;
+ goto cleanup;
if (VIR_STRDUP(backingStore->relPath, src->backingStoreRaw) < 0)
goto cleanup;
@@ -3201,7 +3238,6 @@ virStorageFileGetMetadataRecurse(virStorageSourcePtr src,
backingStore->format = backingFormat;
if (virStorageFileGetMetadataRecurse(backingStore,
- backingStore->path,
uid, gid, allow_probe,
cycle) < 0) {
/* if we fail somewhere midway, just accept and return a
@@ -3215,6 +3251,7 @@ virStorageFileGetMetadataRecurse(virStorageSourcePtr src,
ret = 0;
cleanup:
+ virStorageFileDeinit(src);
virStorageSourceFree(backingStore);
return ret;
}
@@ -3253,12 +3290,6 @@ virStorageFileGetMetadata(virStorageSourcePtr src,
return -1;
if (virStorageSourceGetActualType(src) != VIR_STORAGE_TYPE_NETWORK) {
- if (!(canonPath = canonicalize_file_name(src->path))) {
- virReportSystemError(errno, _("unable to resolve '%s'"),
- src->path);
- goto cleanup;
- }
-
if (!src->relPath &&
VIR_STRDUP(src->relPath, src->path) < 0)
goto cleanup;
@@ -3277,7 +3308,7 @@ virStorageFileGetMetadata(virStorageSourcePtr src,
if (src->format <= VIR_STORAGE_FILE_NONE)
src->format = allow_probe ? VIR_STORAGE_FILE_AUTO : VIR_STORAGE_FILE_RAW;
- ret = virStorageFileGetMetadataRecurse(src, canonPath, uid, gid,
+ ret = virStorageFileGetMetadataRecurse(src, uid, gid,
allow_probe, cycle);
cleanup:
--
1.9.3