storage: split fs storage file code from storage driver backend

The storage file code needs to be run in the hypervisor drivers, while
the storage backend code needs to be run in the storage driver. Split
the source code as a preparatory step for creating separate loadable
modules.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

src/storage/Makefile.inc.am

@@ -14,6 +14,8 @@ STORAGE_DRIVER_SOURCES = \
 STORAGE_DRIVER_FS_SOURCES = \
 	storage/storage_backend_fs.h \
 	storage/storage_backend_fs.c \
+	storage/storage_file_fs.h \
+	storage/storage_file_fs.c \
 	$(NULL)
 
 STORAGE_DRIVER_LVM_SOURCES = \

src/storage/storage_backend_fs.c

@@ -28,17 +28,15 @@
 #include <stdio.h>
 #include <errno.h>
 #include <fcntl.h>
-#include <unistd.h>
 #include <string.h>
 
 #include "virerror.h"
 #include "storage_backend_fs.h"
+#include "storage_file_fs.h"
 #include "storage_util.h"
 #include "storage_conf.h"
-#include "virstoragefilebackend.h"
 #include "vircommand.h"
 #include "viralloc.h"
-#include "virxml.h"
 #include "virfile.h"
 #include "virlog.h"
 #include "virstring.h"
@@ -701,198 +699,6 @@ virStorageBackend virStorageBackendNetFileSystem = {
 #endif /* WITH_STORAGE_FS */
 
 
-typedef struct _virStorageFileBackendFsPriv virStorageFileBackendFsPriv;
-typedef virStorageFileBackendFsPriv *virStorageFileBackendFsPrivPtr;
-
-struct _virStorageFileBackendFsPriv {
-    char *canonpath; /* unique file identifier (canonical path) */
-};
-
-
-static void
-virStorageFileBackendFileDeinit(virStorageSourcePtr src)
-{
-    VIR_DEBUG("deinitializing FS storage file %p (%s:%s)", src,
-              virStorageTypeToString(virStorageSourceGetActualType(src)),
-              src->path);
-
-    virStorageFileBackendFsPrivPtr priv = src->drv->priv;
-
-    VIR_FREE(priv->canonpath);
-    VIR_FREE(priv);
-}
-
-
-static int
-virStorageFileBackendFileInit(virStorageSourcePtr src)
-{
-    virStorageFileBackendFsPrivPtr priv = NULL;
-
-    VIR_DEBUG("initializing FS storage file %p (%s:%s)[%u:%u]", src,
-              virStorageTypeToString(virStorageSourceGetActualType(src)),
-              src->path,
-              (unsigned int)src->drv->uid, (unsigned int)src->drv->gid);
-
-    if (VIR_ALLOC(priv) < 0)
-        return -1;
-
-    src->drv->priv = priv;
-
-    return 0;
-}
-
-
-static int
-virStorageFileBackendFileCreate(virStorageSourcePtr src)
-{
-    int fd = -1;
-    mode_t mode = S_IRUSR;
-
-    if (!src->readonly)
-        mode |= S_IWUSR;
-
-    if ((fd = virFileOpenAs(src->path, O_WRONLY | O_TRUNC | O_CREAT, mode,
-                            src->drv->uid, src->drv->gid, 0)) < 0) {
-        errno = -fd;
-        return -1;
-    }
-
-    VIR_FORCE_CLOSE(fd);
-    return 0;
-}
-
-
-static int
-virStorageFileBackendFileUnlink(virStorageSourcePtr src)
-{
-    return unlink(src->path);
-}
-
-
-static int
-virStorageFileBackendFileStat(virStorageSourcePtr src,
-                              struct stat *st)
-{
-    return stat(src->path, st);
-}
-
-
-static ssize_t
-virStorageFileBackendFileRead(virStorageSourcePtr src,
-                              size_t offset,
-                              size_t len,
-                              char **buf)
-{
-    int fd = -1;
-    ssize_t ret = -1;
-
-    if ((fd = virFileOpenAs(src->path, O_RDONLY, 0,
-                            src->drv->uid, src->drv->gid, 0)) < 0) {
-        virReportSystemError(-fd, _("Failed to open file '%s'"),
-                             src->path);
-        return -1;
-    }
-
-    if (offset > 0) {
-        if (lseek(fd, offset, SEEK_SET) == (off_t) -1) {
-            virReportSystemError(errno, _("cannot seek into '%s'"), src->path);
-            goto cleanup;
-        }
-    }
-
-    if ((ret = virFileReadHeaderFD(fd, len, buf)) < 0) {
-        virReportSystemError(errno,
-                             _("cannot read header '%s'"), src->path);
-        goto cleanup;
-    }
-
- cleanup:
-    VIR_FORCE_CLOSE(fd);
-
-    return ret;
-}
-
-
-static const char *
-virStorageFileBackendFileGetUniqueIdentifier(virStorageSourcePtr src)
-{
-    virStorageFileBackendFsPrivPtr priv = src->drv->priv;
-
-    if (!priv->canonpath) {
-        if (!(priv->canonpath = canonicalize_file_name(src->path))) {
-            virReportSystemError(errno, _("can't canonicalize path '%s'"),
-                                 src->path);
-            return NULL;
-        }
-    }
-
-    return priv->canonpath;
-}
-
-
-static int
-virStorageFileBackendFileAccess(virStorageSourcePtr src,
-                                int mode)
-{
-    return virFileAccessibleAs(src->path, mode,
-                               src->drv->uid, src->drv->gid);
-}
-
-
-static int
-virStorageFileBackendFileChown(const virStorageSource *src,
-                               uid_t uid,
-                               gid_t gid)
-{
-    return chown(src->path, uid, gid);
-}
-
-
-virStorageFileBackend virStorageFileBackendFile = {
-    .type = VIR_STORAGE_TYPE_FILE,
-
-    .backendInit = virStorageFileBackendFileInit,
-    .backendDeinit = virStorageFileBackendFileDeinit,
-
-    .storageFileCreate = virStorageFileBackendFileCreate,
-    .storageFileUnlink = virStorageFileBackendFileUnlink,
-    .storageFileStat = virStorageFileBackendFileStat,
-    .storageFileRead = virStorageFileBackendFileRead,
-    .storageFileAccess = virStorageFileBackendFileAccess,
-    .storageFileChown = virStorageFileBackendFileChown,
-
-    .storageFileGetUniqueIdentifier = virStorageFileBackendFileGetUniqueIdentifier,
-};
-
-
-virStorageFileBackend virStorageFileBackendBlock = {
-    .type = VIR_STORAGE_TYPE_BLOCK,
-
-    .backendInit = virStorageFileBackendFileInit,
-    .backendDeinit = virStorageFileBackendFileDeinit,
-
-    .storageFileStat = virStorageFileBackendFileStat,
-    .storageFileRead = virStorageFileBackendFileRead,
-    .storageFileAccess = virStorageFileBackendFileAccess,
-    .storageFileChown = virStorageFileBackendFileChown,
-
-    .storageFileGetUniqueIdentifier = virStorageFileBackendFileGetUniqueIdentifier,
-};
-
-
-virStorageFileBackend virStorageFileBackendDir = {
-    .type = VIR_STORAGE_TYPE_DIR,
-
-    .backendInit = virStorageFileBackendFileInit,
-    .backendDeinit = virStorageFileBackendFileDeinit,
-
-    .storageFileAccess = virStorageFileBackendFileAccess,
-    .storageFileChown = virStorageFileBackendFileChown,
-
-    .storageFileGetUniqueIdentifier = virStorageFileBackendFileGetUniqueIdentifier,
-};
-
-
 int
 virStorageBackendFsRegister(void)
 {
@@ -907,13 +713,7 @@ virStorageBackendFsRegister(void)
         return -1;
 #endif /* WITH_STORAGE_FS */
 
-    if (virStorageFileBackendRegister(&virStorageFileBackendFile) < 0)
-        return -1;
-
-    if (virStorageFileBackendRegister(&virStorageFileBackendBlock) < 0)
-        return -1;
-
-    if (virStorageFileBackendRegister(&virStorageFileBackendDir) < 0)
+    if (virStorageFileFsRegister() < 0)
         return -1;
 
     return 0;

src/storage/storage_file_fs.c

+/*
+ * storage_file_fs.c: storage file code for FS and directory handling
+ *
+ * Copyright (C) 2007-2018 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Daniel P. Berrange <berrange@redhat.com>
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+
+#include "virerror.h"
+#include "storage_file_fs.h"
+#include "storage_util.h"
+#include "virstoragefilebackend.h"
+#include "vircommand.h"
+#include "viralloc.h"
+#include "virfile.h"
+#include "virlog.h"
+#include "virstring.h"
+
+#define VIR_FROM_THIS VIR_FROM_STORAGE
+
+VIR_LOG_INIT("storage.storage_backend_fs");
+
+
+typedef struct _virStorageFileBackendFsPriv virStorageFileBackendFsPriv;
+typedef virStorageFileBackendFsPriv *virStorageFileBackendFsPrivPtr;
+
+struct _virStorageFileBackendFsPriv {
+    char *canonpath; /* unique file identifier (canonical path) */
+};
+
+
+static void
+virStorageFileBackendFileDeinit(virStorageSourcePtr src)
+{
+    VIR_DEBUG("deinitializing FS storage file %p (%s:%s)", src,
+              virStorageTypeToString(virStorageSourceGetActualType(src)),
+              src->path);
+
+    virStorageFileBackendFsPrivPtr priv = src->drv->priv;
+
+    VIR_FREE(priv->canonpath);
+    VIR_FREE(priv);
+}
+
+
+static int
+virStorageFileBackendFileInit(virStorageSourcePtr src)
+{
+    virStorageFileBackendFsPrivPtr priv = NULL;
+
+    VIR_DEBUG("initializing FS storage file %p (%s:%s)[%u:%u]", src,
+              virStorageTypeToString(virStorageSourceGetActualType(src)),
+              src->path,
+              (unsigned int)src->drv->uid, (unsigned int)src->drv->gid);
+
+    if (VIR_ALLOC(priv) < 0)
+        return -1;
+
+    src->drv->priv = priv;
+
+    return 0;
+}
+
+
+static int
+virStorageFileBackendFileCreate(virStorageSourcePtr src)
+{
+    int fd = -1;
+    mode_t mode = S_IRUSR;
+
+    if (!src->readonly)
+        mode |= S_IWUSR;
+
+    if ((fd = virFileOpenAs(src->path, O_WRONLY | O_TRUNC | O_CREAT, mode,
+                            src->drv->uid, src->drv->gid, 0)) < 0) {
+        errno = -fd;
+        return -1;
+    }
+
+    VIR_FORCE_CLOSE(fd);
+    return 0;
+}
+
+
+static int
+virStorageFileBackendFileUnlink(virStorageSourcePtr src)
+{
+    return unlink(src->path);
+}
+
+
+static int
+virStorageFileBackendFileStat(virStorageSourcePtr src,
+                              struct stat *st)
+{
+    return stat(src->path, st);
+}
+
+
+static ssize_t
+virStorageFileBackendFileRead(virStorageSourcePtr src,
+                              size_t offset,
+                              size_t len,
+                              char **buf)
+{
+    int fd = -1;
+    ssize_t ret = -1;
+
+    if ((fd = virFileOpenAs(src->path, O_RDONLY, 0,
+                            src->drv->uid, src->drv->gid, 0)) < 0) {
+        virReportSystemError(-fd, _("Failed to open file '%s'"),
+                             src->path);
+        return -1;
+    }
+
+    if (offset > 0) {
+        if (lseek(fd, offset, SEEK_SET) == (off_t) -1) {
+            virReportSystemError(errno, _("cannot seek into '%s'"), src->path);
+            goto cleanup;
+        }
+    }
+
+    if ((ret = virFileReadHeaderFD(fd, len, buf)) < 0) {
+        virReportSystemError(errno,
+                             _("cannot read header '%s'"), src->path);
+        goto cleanup;
+    }
+
+ cleanup:
+    VIR_FORCE_CLOSE(fd);
+
+    return ret;
+}
+
+
+static const char *
+virStorageFileBackendFileGetUniqueIdentifier(virStorageSourcePtr src)
+{
+    virStorageFileBackendFsPrivPtr priv = src->drv->priv;
+
+    if (!priv->canonpath) {
+        if (!(priv->canonpath = canonicalize_file_name(src->path))) {
+            virReportSystemError(errno, _("can't canonicalize path '%s'"),
+                                 src->path);
+            return NULL;
+        }
+    }
+
+    return priv->canonpath;
+}
+
+
+static int
+virStorageFileBackendFileAccess(virStorageSourcePtr src,
+                                int mode)
+{
+    return virFileAccessibleAs(src->path, mode,
+                               src->drv->uid, src->drv->gid);
+}
+
+
+static int
+virStorageFileBackendFileChown(const virStorageSource *src,
+                               uid_t uid,
+                               gid_t gid)
+{
+    return chown(src->path, uid, gid);
+}
+
+
+virStorageFileBackend virStorageFileBackendFile = {
+    .type = VIR_STORAGE_TYPE_FILE,
+
+    .backendInit = virStorageFileBackendFileInit,
+    .backendDeinit = virStorageFileBackendFileDeinit,
+
+    .storageFileCreate = virStorageFileBackendFileCreate,
+    .storageFileUnlink = virStorageFileBackendFileUnlink,
+    .storageFileStat = virStorageFileBackendFileStat,
+    .storageFileRead = virStorageFileBackendFileRead,
+    .storageFileAccess = virStorageFileBackendFileAccess,
+    .storageFileChown = virStorageFileBackendFileChown,
+
+    .storageFileGetUniqueIdentifier = virStorageFileBackendFileGetUniqueIdentifier,
+};
+
+
+virStorageFileBackend virStorageFileBackendBlock = {
+    .type = VIR_STORAGE_TYPE_BLOCK,
+
+    .backendInit = virStorageFileBackendFileInit,
+    .backendDeinit = virStorageFileBackendFileDeinit,
+
+    .storageFileStat = virStorageFileBackendFileStat,
+    .storageFileRead = virStorageFileBackendFileRead,
+    .storageFileAccess = virStorageFileBackendFileAccess,
+    .storageFileChown = virStorageFileBackendFileChown,
+
+    .storageFileGetUniqueIdentifier = virStorageFileBackendFileGetUniqueIdentifier,
+};
+
+
+virStorageFileBackend virStorageFileBackendDir = {
+    .type = VIR_STORAGE_TYPE_DIR,
+
+    .backendInit = virStorageFileBackendFileInit,
+    .backendDeinit = virStorageFileBackendFileDeinit,
+
+    .storageFileAccess = virStorageFileBackendFileAccess,
+    .storageFileChown = virStorageFileBackendFileChown,
+
+    .storageFileGetUniqueIdentifier = virStorageFileBackendFileGetUniqueIdentifier,
+};
+
+
+int
+virStorageFileFsRegister(void)
+{
+    if (virStorageFileBackendRegister(&virStorageFileBackendFile) < 0)
+        return -1;
+
+    if (virStorageFileBackendRegister(&virStorageFileBackendBlock) < 0)
+        return -1;
+
+    if (virStorageFileBackendRegister(&virStorageFileBackendDir) < 0)
+        return -1;
+
+    return 0;
+}

src/storage/storage_file_fs.h

+/*
+ * storage_file_fs.h: storage file code for FS and directory handling
+ *
+ * Copyright (C) 2018 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Daniel P. Berrange <berrange@redhat.com>
+ */
+
+#ifndef __VIR_STORAGE_FILE_FS_H__
+# define __VIR_STORAGE_FILE_FS_H__
+
+int virStorageFileFsRegister(void);
+
+#endif /* __VIR_STORAGE_FILE_FS_H__ */