block: Use bdrv_refresh_filename() to pull
Before this patch, bdrv_refresh_filename() is used in a pushing manner:
Whenever the BDS graph is modified, the parents of the modified edges
are supposed to be updated (recursively upwards). However, that is
nonviable, considering that we want child changes not to concern
parents.
Also, in the long run we want a pull model anyway: Here, we would have a
bdrv_filename() function which returns a BDS's filename, freshly
constructed.
This patch is an intermediate step. It adds bdrv_refresh_filename()
calls before every place a BDS.filename value is used. The only
exceptions are protocol drivers that use their own filename, which
clearly would not profit from refreshing that filename before.
Also, bdrv_get_encrypted_filename() is removed along the way (as a user
of BDS.filename), since it is completely unused.
In turn, all of the calls to bdrv_refresh_filename() before this patch
are removed, because we no longer have to call this function on graph
changes.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190201192935.18394-2-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
diff --git a/block.c b/block.c
index 16d59e0..88aa687 100644
--- a/block.c
+++ b/block.c
@@ -323,8 +323,11 @@
void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz,
Error **errp)
{
- char *backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename;
+ char *backed;
+ bdrv_refresh_filename(bs);
+
+ backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename;
bdrv_get_full_backing_filename_from_filename(backed, bs->backing_file,
dest, sz, errp);
}
@@ -1004,6 +1007,8 @@
"node is used as backing hd of '%s'",
bdrv_get_device_or_node_name(parent));
+ bdrv_refresh_filename(backing_hd);
+
parent->open_flags &= ~BDRV_O_NO_BACKING;
pstrcpy(parent->backing_file, sizeof(parent->backing_file),
backing_hd->filename);
@@ -1413,6 +1418,7 @@
}
if (file != NULL) {
+ bdrv_refresh_filename(blk_bs(file));
filename = blk_bs(file)->filename;
} else {
/*
@@ -2334,8 +2340,6 @@
bdrv_unref(backing_hd);
}
- bdrv_refresh_filename(bs);
-
out:
bdrv_refresh_limits(bs, NULL);
}
@@ -2864,8 +2868,6 @@
g_free(child_key_dot);
}
- bdrv_refresh_filename(bs);
-
/* Check if any unknown options were used */
if (qdict_size(options) != 0) {
const QDictEntry *entry = qdict_first(options);
@@ -3310,6 +3312,7 @@
if (local_err != NULL) {
error_propagate(errp, local_err);
} else {
+ bdrv_refresh_filename(reopen_state->bs);
error_setg(errp, "failed while preparing to reopen image '%s'",
reopen_state->bs->filename);
}
@@ -3937,7 +3940,10 @@
/* success - we can delete the intermediate states, and link top->base */
/* TODO Check graph modification op blockers (BLK_PERM_GRAPH_MOD) once
* we've figured out how they should work. */
- backing_file_str = backing_file_str ? backing_file_str : base->filename;
+ if (!backing_file_str) {
+ bdrv_refresh_filename(base);
+ backing_file_str = base->filename;
+ }
QLIST_FOREACH_SAFE(c, &top->parents, next_parent, next) {
/* Check whether we are allowed to switch c from top to base */
@@ -4485,16 +4491,6 @@
return bs->supported_zero_flags & BDRV_REQ_MAY_UNMAP;
}
-const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
-{
- if (bs->backing && bs->backing->bs->encrypted)
- return bs->backing_file;
- else if (bs->encrypted)
- return bs->filename;
- else
- return NULL;
-}
-
void bdrv_get_backing_filename(BlockDriverState *bs,
char *filename, int filename_size)
{
@@ -4615,6 +4611,9 @@
is_protocol = path_has_protocol(backing_file);
+ /* This will recursively refresh everything in the backing chain */
+ bdrv_refresh_filename(bs);
+
for (curr_bs = bs; curr_bs->backing; curr_bs = curr_bs->backing->bs) {
/* If either of the filename paths is actually a protocol, then