[Qemu-devel] [PATCH V3 2/4] block: move snapshot code in block.c to block/snapshot.c

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

All snapshot related code, except bdrv_snapshot_dump() and
bdrv_is_snapshot(), is moved to block/snapshot.c. bdrv_snapshot_dump()
will be moved to another file later. bdrv_is_snapshot() is not related
with internal snapshot. It also fixes small code style errors reported
by check script.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
---
 block.c                  |  100 -----------------------------
 block/Makefile.objs      |    1 +
 block/snapshot.c         |  157 ++++++++++++++++++++++++++++++++++++++++++++++
 include/block/block.h    |   26 ++------
 include/block/snapshot.h |   53 ++++++++++++++++
 savevm.c                 |   23 +-------
 6 files changed, 217 insertions(+), 143 deletions(-)
 create mode 100644 block/snapshot.c
 create mode 100644 include/block/snapshot.h

diff --git a/block.c b/block.c
index 478a3b2..67cafb7 100644
--- a/block.c
+++ b/block.c
@@ -3346,111 +3346,11 @@ bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag)
     return false;
 }
 
-/**************************************************************/
-/* handling of snapshots */
-
-int bdrv_can_snapshot(BlockDriverState *bs)
-{
-    BlockDriver *drv = bs->drv;
-    if (!drv || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
-        return 0;
-    }
-
-    if (!drv->bdrv_snapshot_create) {
-        if (bs->file != NULL) {
-            return bdrv_can_snapshot(bs->file);
-        }
-        return 0;
-    }
-
-    return 1;
-}
-
 int bdrv_is_snapshot(BlockDriverState *bs)
 {
     return !!(bs->open_flags & BDRV_O_SNAPSHOT);
 }
 
-int bdrv_snapshot_create(BlockDriverState *bs,
-                         QEMUSnapshotInfo *sn_info)
-{
-    BlockDriver *drv = bs->drv;
-    if (!drv)
-        return -ENOMEDIUM;
-    if (drv->bdrv_snapshot_create)
-        return drv->bdrv_snapshot_create(bs, sn_info);
-    if (bs->file)
-        return bdrv_snapshot_create(bs->file, sn_info);
-    return -ENOTSUP;
-}
-
-int bdrv_snapshot_goto(BlockDriverState *bs,
-                       const char *snapshot_id)
-{
-    BlockDriver *drv = bs->drv;
-    int ret, open_ret;
-
-    if (!drv)
-        return -ENOMEDIUM;
-    if (drv->bdrv_snapshot_goto)
-        return drv->bdrv_snapshot_goto(bs, snapshot_id);
-
-    if (bs->file) {
-        drv->bdrv_close(bs);
-        ret = bdrv_snapshot_goto(bs->file, snapshot_id);
-        open_ret = drv->bdrv_open(bs, NULL, bs->open_flags);
-        if (open_ret < 0) {
-            bdrv_delete(bs->file);
-            bs->drv = NULL;
-            return open_ret;
-        }
-        return ret;
-    }
-
-    return -ENOTSUP;
-}
-
-int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
-{
-    BlockDriver *drv = bs->drv;
-    if (!drv)
-        return -ENOMEDIUM;
-    if (drv->bdrv_snapshot_delete)
-        return drv->bdrv_snapshot_delete(bs, snapshot_id);
-    if (bs->file)
-        return bdrv_snapshot_delete(bs->file, snapshot_id);
-    return -ENOTSUP;
-}
-
-int bdrv_snapshot_list(BlockDriverState *bs,
-                       QEMUSnapshotInfo **psn_info)
-{
-    BlockDriver *drv = bs->drv;
-    if (!drv)
-        return -ENOMEDIUM;
-    if (drv->bdrv_snapshot_list)
-        return drv->bdrv_snapshot_list(bs, psn_info);
-    if (bs->file)
-        return bdrv_snapshot_list(bs->file, psn_info);
-    return -ENOTSUP;
-}
-
-int bdrv_snapshot_load_tmp(BlockDriverState *bs,
-        const char *snapshot_name)
-{
-    BlockDriver *drv = bs->drv;
-    if (!drv) {
-        return -ENOMEDIUM;
-    }
-    if (!bs->read_only) {
-        return -EINVAL;
-    }
-    if (drv->bdrv_snapshot_load_tmp) {
-        return drv->bdrv_snapshot_load_tmp(bs, snapshot_name);
-    }
-    return -ENOTSUP;
-}
-
 /* backing_file can either be relative, or absolute, or a protocol.  If it is
  * relative, it must be relative to the chain.  So, passing in bs->filename
  * from a BDS as backing_file should not be done, as that may be relative to
diff --git a/block/Makefile.objs b/block/Makefile.objs
index 5f0358a..8670999 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -4,6 +4,7 @@ block-obj-y += qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluster.o
 block-obj-y += qed-check.o
 block-obj-y += vhdx.o
 block-obj-y += parallels.o blkdebug.o blkverify.o
+block-obj-y += snapshot.o
 block-obj-$(CONFIG_WIN32) += raw-win32.o win32-aio.o
 block-obj-$(CONFIG_POSIX) += raw-posix.o
 block-obj-$(CONFIG_LINUX_AIO) += linux-aio.o
diff --git a/block/snapshot.c b/block/snapshot.c
new file mode 100644
index 0000000..6c6d9de
--- /dev/null
+++ b/block/snapshot.c
@@ -0,0 +1,157 @@
+/*
+ * Block layer snapshot related functions
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "block/snapshot.h"
+#include "block/block_int.h"
+
+int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
+                       const char *name)
+{
+    QEMUSnapshotInfo *sn_tab, *sn;
+    int nb_sns, i, ret;
+
+    ret = -ENOENT;
+    nb_sns = bdrv_snapshot_list(bs, &sn_tab);
+    if (nb_sns < 0) {
+        return ret;
+    }
+    for (i = 0; i < nb_sns; i++) {
+        sn = &sn_tab[i];
+        if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
+            *sn_info = *sn;
+            ret = 0;
+            break;
+        }
+    }
+    g_free(sn_tab);
+    return ret;
+}
+
+int bdrv_can_snapshot(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
+        return 0;
+    }
+
+    if (!drv->bdrv_snapshot_create) {
+        if (bs->file != NULL) {
+            return bdrv_can_snapshot(bs->file);
+        }
+        return 0;
+    }
+
+    return 1;
+}
+
+int bdrv_snapshot_create(BlockDriverState *bs,
+                         QEMUSnapshotInfo *sn_info)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_create) {
+        return drv->bdrv_snapshot_create(bs, sn_info);
+    }
+    if (bs->file) {
+        return bdrv_snapshot_create(bs->file, sn_info);
+    }
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_goto(BlockDriverState *bs,
+                       const char *snapshot_id)
+{
+    BlockDriver *drv = bs->drv;
+    int ret, open_ret;
+
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_goto) {
+        return drv->bdrv_snapshot_goto(bs, snapshot_id);
+    }
+
+    if (bs->file) {
+        drv->bdrv_close(bs);
+        ret = bdrv_snapshot_goto(bs->file, snapshot_id);
+        open_ret = drv->bdrv_open(bs, NULL, bs->open_flags);
+        if (open_ret < 0) {
+            bdrv_delete(bs->file);
+            bs->drv = NULL;
+            return open_ret;
+        }
+        return ret;
+    }
+
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_delete) {
+        return drv->bdrv_snapshot_delete(bs, snapshot_id);
+    }
+    if (bs->file) {
+        return bdrv_snapshot_delete(bs->file, snapshot_id);
+    }
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_list(BlockDriverState *bs,
+                       QEMUSnapshotInfo **psn_info)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_list) {
+        return drv->bdrv_snapshot_list(bs, psn_info);
+    }
+    if (bs->file) {
+        return bdrv_snapshot_list(bs->file, psn_info);
+    }
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_load_tmp(BlockDriverState *bs,
+        const char *snapshot_name)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (!bs->read_only) {
+        return -EINVAL;
+    }
+    if (drv->bdrv_snapshot_load_tmp) {
+        return drv->bdrv_snapshot_load_tmp(bs, snapshot_name);
+    }
+    return -ENOTSUP;
+}
diff --git a/include/block/block.h b/include/block/block.h
index 38263b9..725c7fb 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -7,6 +7,11 @@
 #include "block/coroutine.h"
 #include "qapi/qmp/qobject.h"
 #include "qapi-types.h"
+/*
+ * snapshot.h is needed since bdrv_snapshot_dump(), it can be removed when the
+ * function is moved to other file.
+ */
+#include "block/snapshot.h"
 
 /* block.c */
 typedef struct BlockDriver BlockDriver;
@@ -27,17 +32,6 @@ typedef struct BlockFragInfo {
     uint64_t compressed_clusters;
 } BlockFragInfo;
 
-typedef struct QEMUSnapshotInfo {
-    char id_str[128]; /* unique snapshot id */
-    /* the following fields are informative. They are not needed for
-       the consistency of the snapshot */
-    char name[256]; /* user chosen name */
-    uint64_t vm_state_size; /* VM state info size */
-    uint32_t date_sec; /* UTC date of the snapshot */
-    uint32_t date_nsec;
-    uint64_t vm_clock_nsec; /* VM clock relative to boot */
-} QEMUSnapshotInfo;
-
 /* Callbacks for block device models */
 typedef struct BlockDevOps {
     /*
@@ -330,17 +324,7 @@ void bdrv_get_full_backing_filename(BlockDriverState *bs,
                                     char *dest, size_t sz);
 BlockInfo *bdrv_query_info(BlockDriverState *s);
 BlockStats *bdrv_query_stats(const BlockDriverState *bs);
-int bdrv_can_snapshot(BlockDriverState *bs);
 int bdrv_is_snapshot(BlockDriverState *bs);
-int bdrv_snapshot_create(BlockDriverState *bs,
-                         QEMUSnapshotInfo *sn_info);
-int bdrv_snapshot_goto(BlockDriverState *bs,
-                       const char *snapshot_id);
-int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
-int bdrv_snapshot_list(BlockDriverState *bs,
-                       QEMUSnapshotInfo **psn_info);
-int bdrv_snapshot_load_tmp(BlockDriverState *bs,
-                           const char *snapshot_name);
 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn);
 
 char *get_human_readable_size(char *buf, int buf_size, int64_t size);
diff --git a/include/block/snapshot.h b/include/block/snapshot.h
new file mode 100644
index 0000000..eaf61f0
--- /dev/null
+++ b/include/block/snapshot.h
@@ -0,0 +1,53 @@
+/*
+ * Block layer snapshot related functions
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef SNAPSHOT_H
+#define SNAPSHOT_H
+
+#include "qemu-common.h"
+
+typedef struct QEMUSnapshotInfo {
+    char id_str[128]; /* unique snapshot id */
+    /* the following fields are informative. They are not needed for
+       the consistency of the snapshot */
+    char name[256]; /* user chosen name */
+    uint64_t vm_state_size; /* VM state info size */
+    uint32_t date_sec; /* UTC date of the snapshot */
+    uint32_t date_nsec;
+    uint64_t vm_clock_nsec; /* VM clock relative to boot */
+} QEMUSnapshotInfo;
+
+int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
+                       const char *name);
+int bdrv_can_snapshot(BlockDriverState *bs);
+int bdrv_snapshot_create(BlockDriverState *bs,
+                         QEMUSnapshotInfo *sn_info);
+int bdrv_snapshot_goto(BlockDriverState *bs,
+                       const char *snapshot_id);
+int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
+int bdrv_snapshot_list(BlockDriverState *bs,
+                       QEMUSnapshotInfo **psn_info);
+int bdrv_snapshot_load_tmp(BlockDriverState *bs,
+                           const char *snapshot_name);
+#endif
diff --git a/savevm.c b/savevm.c
index baa1a09..ab53a02 100644
--- a/savevm.c
+++ b/savevm.c
@@ -40,6 +40,7 @@
 #include "trace.h"
 #include "qemu/bitops.h"
 #include "qemu/iov.h"
+#include "block/snapshot.h"
 
 #define SELF_ANNOUNCE_ROUNDS 5
 
@@ -2273,28 +2274,6 @@ static BlockDriverState *find_vmstate_bs(void)
     return NULL;
 }
 
-static int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
-                              const char *name)
-{
-    QEMUSnapshotInfo *sn_tab, *sn;
-    int nb_sns, i, ret;
-
-    ret = -ENOENT;
-    nb_sns = bdrv_snapshot_list(bs, &sn_tab);
-    if (nb_sns < 0)
-        return ret;
-    for(i = 0; i < nb_sns; i++) {
-        sn = &sn_tab[i];
-        if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
-            *sn_info = *sn;
-            ret = 0;
-            break;
-        }
-    }
-    g_free(sn_tab);
-    return ret;
-}
-
 /*
  * Deletes snapshots of a given name in all opened images.
  */
-- 
1.7.1