Signed-off-by: Benoit Canet <ben...@irqsave.net>
---
block/quorum.c | 113 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 113 insertions(+)
diff --git a/block/quorum.c b/block/quorum.c
index bab6175..f228428 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -52,11 +52,124 @@ struct QuorumAIOCB {
int vote_ret;
};
+/* Valid quorum filenames look like
+ * quorum:n/m:path/to/image_1, ... ,path/to/image_m
+ */
+static int quorum_open(BlockDriverState *bs, const char *filename, int flags)
+{
+ BDRVQuorumState *s = bs->opaque;
+ int escape, i, j, len, ret = 0;
+ char *a, *b, *names;
+
+ /* Parse the quorum: prefix */
+ if (strncmp(filename, "quorum:", strlen("quorum:"))) {
+ return -EINVAL;
+ }
+
+ filename += strlen("quorum:");
+
+ /* Get n */
+ errno = 0;
+ s->n = strtoul(filename, &a, 10);
+ if (*a != '/' || errno) {
+ return -EINVAL;
+ }
+ a += 1;
+
+ /* Get m */
+ errno = 0;
+ s->m = strtoul(a, &b, 10);
+ if (*b != ':' || errno) {
+ return -EINVAL;
+ }
+ b += 1;
+
+ if (s->n < 1 || s->m < 2) {
+ return -EINVAL;
+ }
+
+ if (s->n > s->m) {
+ return -EINVAL;
+ }
+
+ s->bs = g_malloc0(sizeof(BlockDriverState *) * s->m);
+ /* Two allocations for all filenames: simpler to free */
+ s->filenames = g_malloc0(sizeof(char *) * s->m);
+ names = g_strdup(b);
+
+ /* Get the filenames pointers */
+ escape = 0;
+ s->filenames[0] = names;
+ len = strlen(names);
+ for (i = 0, j = 1; i < len && j < s->m; i++) {
+ if (!escape && names[i] == ':') {
+ names[i] = '\0';
+ s->filenames[j] = names + i + 1;
+ j += 1;
+ }
+
+ if (!escape && names[i] == '\\') {
+ escape = 1;
+ } else {
+ escape = 0;
+ }
+ }
+
+ if (j != s->m) {
+ ret = -EINVAL;
+ goto free_exit;
+ }
+
+ /* Open files */
+ for (i = 0; i < s->m; i++) {
+ s->bs[i] = bdrv_new("");
+ ret = bdrv_open(s->bs[i], s->filenames[i], flags, NULL);
+ if (ret < 0) {
+ goto error_exit;
+ }
+ }
+
+ goto exit;
+
+error_exit:
+ for (; i >= 0; i--) {
+ bdrv_delete(s->bs[i]);
+ s->bs[i] = NULL;
+ }
+free_exit:
+ g_free(s->filenames[0]);
+ g_free(s->filenames);
+ s->filenames = NULL;
+ g_free(s->bs);
+exit:
+ return ret;
+}
+
+static void quorum_close(BlockDriverState *bs)
+{
+ BDRVQuorumState *s = bs->opaque;
+ int i;
+
+ for (i = 0; i < s->m; i++) {
+ /* Ensure writes reach stable storage */
+ bdrv_flush(s->bs[i]);
+ bdrv_delete(s->bs[i]);
+ }
+
+ g_free(s->filenames[0]);
+ g_free(s->filenames);
+ s->filenames = NULL;
+ g_free(s->bs);
+}
+
static BlockDriver bdrv_quorum = {
.format_name = "quorum",
.protocol_name = "quorum",
.instance_size = sizeof(BDRVQuorumState),
+
+ .bdrv_file_open = quorum_open,
+ .bdrv_close = quorum_close,
};
static void bdrv_quorum_init(void)
--
1.7.9.5
