10:49 a.m.
Add APIs that will allow to use the storage driver to assist in
operations on files even for remote filesystems without native
representation as files in the host.
---
Notes:
Version 6:
- rewrite due to change of exporting approach
Version 5:
- adapt to error reporting change
src/storage/storage_backend.c | 37 +++++++++++
src/storage/storage_backend.h | 41 ++++++++++++
src/storage/storage_driver.c | 145 ++++++++++++++++++++++++++++++++++++++++++
src/storage/storage_driver.h | 32 +++++++++-
tests/Makefile.am | 3 +
5 files changed, 257 insertions(+), 1 deletion(-)
diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c
index 19fb1f0..b59b5b7 100644
--- a/src/storage/storage_backend.c
+++ b/src/storage/storage_backend.c
@@ -121,6 +121,12 @@ static virStorageBackendPtr backends[] = {
NULL
};
+
+static virStorageFileBackendPtr fileBackends[] = {
+ NULL
+};
+
+
enum {
TOOL_QEMU_IMG,
TOOL_KVM_IMG,
@@ -1152,6 +1158,37 @@ virStorageBackendForType(int type)
}
+virStorageFileBackendPtr
+virStorageFileBackendForType(int type,
+ int protocol)
+{
+ size_t i;
+
+ for (i = 0; fileBackends[i]; i++) {
+ if (fileBackends[i]->type == type) {
+ if (type == VIR_DOMAIN_DISK_TYPE_NETWORK &&
+ fileBackends[i]->protocol != protocol)
+ continue;
+
+ return fileBackends[i];
+ }
+ }
+
+ if (type == VIR_DOMAIN_DISK_TYPE_NETWORK) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("missing storage backend for network files "
+ "using %s protocol"),
+ virDomainDiskProtocolTypeToString(protocol));
+ } else {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("missing storage backend for '%s' storage"),
+ virDomainDiskTypeToString(type));
+ }
+
+ return NULL;
+}
+
+
/*
* Allows caller to silently ignore files with improper mode
*
diff --git a/src/storage/storage_backend.h b/src/storage/storage_backend.h
index 378bc4d..1c7ad1e 100644
--- a/src/storage/storage_backend.h
+++ b/src/storage/storage_backend.h
@@ -29,6 +29,7 @@
# include "internal.h"
# include "storage_conf.h"
# include "vircommand.h"
+# include "storage_driver.h"
typedef char * (*virStorageBackendFindPoolSources)(virConnectPtr conn,
const char *srcSpec,
@@ -189,4 +190,44 @@ virStorageBackendCreateQemuImgCmd(virConnectPtr conn,
const char *create_tool,
int imgformat);
+/* ------- virStorageFile backends ------------ */
+typedef int
+(*virStorageFileBackendInit)(virStorageFilePtr file);
+
+typedef void
+(*virStorageFileBackendDeinit)(virStorageFilePtr file);
+
+typedef int
+(*virStorageFileBackendCreate)(virStorageFilePtr file);
+
+typedef int
+(*virStorageFileBackendUnlink)(virStorageFilePtr file);
+
+typedef int
+(*virStorageFileBackendStat)(virStorageFilePtr file,
+ struct stat *st);
+
+typedef struct _virStorageFileBackend virStorageFileBackend;
+typedef virStorageFileBackend *virStorageFileBackendPtr;
+
+virStorageFileBackendPtr virStorageFileBackendForType(int type, int protocol);
+
+struct _virStorageFileBackend {
+ int type;
+ int protocol;
+
+ /* All storage file callbacks may be omitted if not implemented */
+
+ /* The following group of callbacks is expected to set a libvirt
+ * error on failure. */
+ virStorageFileBackendInit backendInit;
+ virStorageFileBackendDeinit backendDeinit;
+
+ /* The following group of callbacks is expected to set errno
+ * and return -1 on error. No libvirt error shall be reported */
+ virStorageFileBackendCreate storageFileCreate;
+ virStorageFileBackendUnlink storageFileUnlink;
+ virStorageFileBackendStat storageFileStat;
+};
+
#endif /* __VIR_STORAGE_BACKEND_H__ */
diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
index 2f7b2e5..64451c5 100644
--- a/src/storage/storage_driver.c
+++ b/src/storage/storage_driver.c
@@ -2589,6 +2589,7 @@ cleanup:
return ret;
}
+
static virStorageDriver storageDriver = {
.name = "storage",
.storageOpen = storageOpen, /* 0.4.0 */
@@ -2653,3 +2654,147 @@ int storageRegister(void)
virRegisterStateDriver(&stateDriver);
return 0;
}
+
+
+/* ----------- file handlers cooperating with storage driver --------------- */
+void
+virStorageFileFree(virStorageFilePtr file)
+{
+ if (!file)
+ return;
+
+ if (file->backend &&
+ file->backend->backendDeinit)
+ file->backend->backendDeinit(file);
+
+ VIR_FREE(file->path);
+ virDomainDiskHostDefFree(file->nhosts, file->hosts);
+ VIR_FREE(file);
+}
+
+
+static virStorageFilePtr
+virStorageFileInitInternal(int type,
+ const char *path,
+ int protocol,
+ size_t nhosts,
+ virDomainDiskHostDefPtr hosts)
+{
+ virStorageFilePtr file = NULL;
+
+ if (VIR_ALLOC(file) < 0)
+ return NULL;
+
+ file->type = type;
+ file->protocol = protocol;
+ file->nhosts = nhosts;
+
+ if (VIR_STRDUP(file->path, path) < 0)
+ goto error;
+
+ if (!(file->hosts = virDomainDiskHostDefCopy(nhosts, hosts)))
+ goto error;
+
+ if (!(file->backend = virStorageFileBackendForType(file->type,
+ file->protocol)))
+ goto error;
+
+ if (file->backend->backendInit &&
+ file->backend->backendInit(file) < 0)
+ goto error;
+
+ return file;
+
+error:
+ VIR_FREE(file->path);
+ virDomainDiskHostDefFree(file->nhosts, file->hosts);
+ VIR_FREE(file);
+ return NULL;
+}
+
+
+virStorageFilePtr
+virStorageFileInitFromDiskDef(virDomainDiskDefPtr disk)
+{
+ return virStorageFileInitInternal(virDomainDiskGetActualType(disk),
+ disk->src,
+ disk->protocol,
+ disk->nhosts,
+ disk->hosts);
+}
+
+
+virStorageFilePtr
+virStorageFileInitFromSnapshotDef(virDomainSnapshotDiskDefPtr disk)
+{
+ return virStorageFileInitInternal(virDomainSnapshotDiskGetActualType(disk),
+ disk->file,
+ disk->protocol,
+ disk->nhosts,
+ disk->hosts);
+}
+
+
+
+/**
+ * virStorageFileCreate: Creates an empty storage file via storage driver
+ *
+ * @file: file structure pointing to the file
+ *
+ * Returns 0 on success, -2 if the function isn't supported by the backend,
+ * -1 on other failure. Errno is set in case of failure.
+ */
+int
+virStorageFileCreate(virStorageFilePtr file)
+{
+ if (!file->backend->storageFileCreate) {
+ errno = ENOSYS;
+ return -2;
+ }
+
+ return file->backend->storageFileCreate(file);
+}
+
+
+/**
+ * virStorageFileUnlink: Unlink storage file via storage driver
+ *
+ * @file: file structure pointing to the file
+ *
+ * Unlinks the file described by the @file structure.
+ *
+ * Returns 0 on success, -2 if the function isn't supported by the backend,
+ * -1 on other failure. Errno is set in case of failure.
+ */
+int
+virStorageFileUnlink(virStorageFilePtr file)
+{
+ if (!file->backend->storageFileUnlink) {
+ errno = ENOSYS;
+ return -2;
+ }
+
+ return file->backend->storageFileUnlink(file);
+}
+
+
+/**
+ * virStorageFileStat: returns stat struct of a file via storage driver
+ *
+ * @file: file structure pointing to the file
+ * @stat: stat structure to return data
+ *
+ * Returns 0 on success, -2 if the function isn't supported by the backend,
+ * -1 on other failure. Errno is set in case of failure.
+*/
+int
+virStorageFileStat(virStorageFilePtr file,
+ struct stat *st)
+{
+ if (!(file->backend->storageFileStat)) {
+ errno = ENOSYS;
+ return -2;
+ }
+
+ return file->backend->storageFileStat(file, st);
+}
diff --git a/src/storage/storage_driver.h b/src/storage/storage_driver.h
index 8ccfd75..993bba5 100644
--- a/src/storage/storage_driver.h
+++ b/src/storage/storage_driver.h
@@ -1,7 +1,7 @@
/*
* storage_driver.h: core driver for storage APIs
*
- * Copyright (C) 2006-2008 Red Hat, Inc.
+ * Copyright (C) 2006-2008, 2014 Red Hat, Inc.
* Copyright (C) 2006-2008 Daniel P. Berrange
*
* This library is free software; you can redistribute it and/or
@@ -25,6 +25,36 @@
# define __VIR_STORAGE_DRIVER_H__
# include "storage_conf.h"
+# include "conf/domain_conf.h"
+# include "conf/snapshot_conf.h"
+
+typedef struct _virStorageFileBackend virStorageFileBackend;
+typedef virStorageFileBackend *virStorageFileBackendPtr;
+
+typedef struct _virStorageFile virStorageFile;
+typedef virStorageFile *virStorageFilePtr;
+struct _virStorageFile {
+ virStorageFileBackendPtr backend;
+ void *priv;
+
+ char *path;
+ int type;
+ int protocol;
+
+ size_t nhosts;
+ virDomainDiskHostDefPtr hosts;
+};
+
+virStorageFilePtr
+virStorageFileInitFromDiskDef(virDomainDiskDefPtr disk);
+virStorageFilePtr
+virStorageFileInitFromSnapshotDef(virDomainSnapshotDiskDefPtr disk);
+void virStorageFileFree(virStorageFilePtr file);
+
+int virStorageFileCreate(virStorageFilePtr file);
+int virStorageFileUnlink(virStorageFilePtr file);
+int virStorageFileStat(virStorageFilePtr file,
+ struct stat *stat);
int storageRegister(void);
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 62a19cb..0718a69 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -433,6 +433,9 @@ qemu_LDADDS = ../src/libvirt_driver_qemu_impl.la
if WITH_NETWORK
qemu_LDADDS += ../src/libvirt_driver_network_impl.la
endif WITH_NETWORK
+if WITH_STORAGE
+qemu_LDADDS += ../src/libvirt_driver_storage_impl.la
+endif WITH_STORAGE
if WITH_DTRACE_PROBES
qemu_LDADDS += ../src/libvirt_qemu_probes.lo
endif WITH_DTRACE_PROBES
--
1.8.5.3