block/ssh: Implement .bdrv_refresh_filename()

[qemu.git] / block / commit.c

diff --git a/block/commit.c b/block/commit.c
index a2da5740b0273c78734748ffe3749398381a51bb..27537d995b6050ebb2992e6833c2af77fbf331a7 100644 (file)
--- a/block/commit.c
+++ b/block/commit.c
@@ -38,7 +38,8 @@ typedef struct CommitBlockJob {
     BlockBackend *base;
     BlockDriverState *base_bs;
     BlockdevOnError on_error;
-    int base_flags;
+    bool base_read_only;
+    bool chain_frozen;
     char *backing_file_str;
 } CommitBlockJob;
 
@@ -47,21 +48,15 @@ static int coroutine_fn commit_populate(BlockBackend *bs, BlockBackend *base,
                                         void *buf)
 {
     int ret = 0;
-    QEMUIOVector qiov;
-    struct iovec iov = {
-        .iov_base = buf,
-        .iov_len = bytes,
-    };
 
     assert(bytes < SIZE_MAX);
-    qemu_iovec_init_external(&qiov, &iov, 1);
 
-    ret = blk_co_preadv(bs, offset, qiov.size, &qiov, 0);
+    ret = blk_co_pread(bs, offset, bytes, buf, 0);
     if (ret < 0) {
         return ret;
     }
 
-    ret = blk_co_pwritev(base, offset, qiov.size, &qiov, 0);
+    ret = blk_co_pwrite(base, offset, bytes, buf, 0);
     if (ret < 0) {
         return ret;
     }
@@ -73,6 +68,9 @@ static int commit_prepare(Job *job)
 {
     CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
 
+    bdrv_unfreeze_backing_chain(s->commit_top_bs, s->base_bs);
+    s->chain_frozen = false;
+
     /* Remove base node parent that still uses BLK_PERM_WRITE/RESIZE before
      * the normal backing chain can be restored. */
     blk_unref(s->base);
@@ -89,6 +87,10 @@ static void commit_abort(Job *job)
     CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
     BlockDriverState *top_bs = blk_bs(s->top);
 
+    if (s->chain_frozen) {
+        bdrv_unfreeze_backing_chain(s->commit_top_bs, s->base_bs);
+    }
+
     /* Make sure commit_top_bs and top stay around until bdrv_replace_node() */
     bdrv_ref(top_bs);
     bdrv_ref(s->commit_top_bs);
@@ -124,8 +126,8 @@ static void commit_clean(Job *job)
     /* restore base open flags here if appropriate (e.g., change the base back
      * to r/o). These reopens do not need to be atomic, since we won't abort
      * even on failure here */
-    if (s->base_flags != bdrv_get_flags(s->base_bs)) {
-        bdrv_reopen(s->base_bs, s->base_flags, NULL);
+    if (s->base_read_only) {
+        bdrv_reopen_set_read_only(s->base_bs, true, NULL);
     }
 
     g_free(s->backing_file_str);
@@ -230,9 +232,8 @@ static int coroutine_fn bdrv_commit_top_preadv(BlockDriverState *bs,
     return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags);
 }
 
-static void bdrv_commit_top_refresh_filename(BlockDriverState *bs, QDict *opts)
+static void bdrv_commit_top_refresh_filename(BlockDriverState *bs)
 {
-    bdrv_refresh_filename(bs->backing->bs);
     pstrcpy(bs->exact_filename, sizeof(bs->exact_filename),
             bs->backing->bs->filename);
 }
@@ -264,7 +265,6 @@ void commit_start(const char *job_id, BlockDriverState *bs,
                   const char *filter_node_name, Error **errp)
 {
     CommitBlockJob *s;
-    int orig_base_flags;
     BlockDriverState *iter;
     BlockDriverState *commit_top_bs = NULL;
     Error *local_err = NULL;
@@ -283,11 +283,9 @@ void commit_start(const char *job_id, BlockDriverState *bs,
     }
 
     /* convert base to r/w, if necessary */
-    orig_base_flags = bdrv_get_flags(base);
-    if (!(orig_base_flags & BDRV_O_RDWR)) {
-        bdrv_reopen(base, orig_base_flags | BDRV_O_RDWR, &local_err);
-        if (local_err != NULL) {
-            error_propagate(errp, local_err);
+    s->base_read_only = bdrv_is_read_only(base);
+    if (s->base_read_only) {
+        if (bdrv_reopen_set_read_only(base, false, errp) != 0) {
             goto fail;
         }
     }
@@ -339,6 +337,11 @@ void commit_start(const char *job_id, BlockDriverState *bs,
         }
     }
 
+    if (bdrv_freeze_backing_chain(commit_top_bs, base, errp) < 0) {
+        goto fail;
+    }
+    s->chain_frozen = true;
+
     ret = block_job_add_bdrv(&s->common, "base", base, 0, BLK_PERM_ALL, errp);
     if (ret < 0) {
         goto fail;
@@ -363,7 +366,6 @@ void commit_start(const char *job_id, BlockDriverState *bs,
         goto fail;
     }
 
-    s->base_flags = orig_base_flags;
     s->backing_file_str = g_strdup(backing_file_str);
     s->on_error = on_error;
 
@@ -372,16 +374,24 @@ void commit_start(const char *job_id, BlockDriverState *bs,
     return;
 
 fail:
+    if (s->chain_frozen) {
+        bdrv_unfreeze_backing_chain(commit_top_bs, base);
+    }
     if (s->base) {
         blk_unref(s->base);
     }
     if (s->top) {
         blk_unref(s->top);
     }
+    if (s->base_read_only) {
+        bdrv_reopen_set_read_only(base, true, NULL);
+    }
+    job_early_fail(&s->common.job);
+    /* commit_top_bs has to be replaced after deleting the block job,
+     * otherwise this would fail because of lack of permissions. */
     if (commit_top_bs) {
         bdrv_replace_node(commit_top_bs, top, &error_abort);
     }
-    job_early_fail(&s->common.job);
 }
 
 
@@ -395,7 +405,7 @@ int bdrv_commit(BlockDriverState *bs)
     BlockDriverState *commit_top_bs = NULL;
     BlockDriver *drv = bs->drv;
     int64_t offset, length, backing_length;
-    int ro, open_flags;
+    int ro;
     int64_t n;
     int ret = 0;
     uint8_t *buf = NULL;
@@ -414,10 +424,9 @@ int bdrv_commit(BlockDriverState *bs)
     }
 
     ro = bs->backing->bs->read_only;
-    open_flags =  bs->backing->bs->open_flags;
 
     if (ro) {
-        if (bdrv_reopen(bs->backing->bs, open_flags | BDRV_O_RDWR, NULL)) {
+        if (bdrv_reopen_set_read_only(bs->backing->bs, false, NULL)) {
             return -EACCES;
         }
     }
@@ -527,7 +536,7 @@ ro_cleanup:
 
     if (ro) {
         /* ignoring error return here */
-        bdrv_reopen(bs->backing->bs, open_flags & ~BDRV_O_RDWR, NULL);
+        bdrv_reopen_set_read_only(bs->backing->bs, true, NULL);
     }
 
     return ret;