[07/12] rbd: allow configuration of rados from the rbd filename

diff --git a/block/rbd.c b/block/rbd.c
index 2cee70d..edf1086 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -23,13 +23,17 @@ 
 /*
  * When specifying the image filename use:
  *
- * rbd:poolname/devicename
+ * rbd:poolname/devicename[@snapshotname][:option1=value1[:option2=value2...]]
  *
  * poolname must be the name of an existing rados pool
  *
  * devicename is the basename for all objects used to
  * emulate the raw device.
  *
+ * Each option given is used to configure rados, and may be
+ * any Ceph option, or "conf". The "conf" option specifies
+ * a Ceph configuration file to read.
+ *
  * Metadata information (image size, ...) is stored in an
  * object with the name "devicename.rbd".
  *
@@ -123,7 +127,8 @@  static int qemu_rbd_next_tok(char *dst, int dst_len,
 static int qemu_rbd_parsename(const char *filename,
                               char *pool, int pool_len,
                               char *snap, int snap_len,
-                              char *name, int name_len)
+                              char *name, int name_len,
+                              char *conf, int conf_len)
 {
     const char *start;
     char *p, *buf;
@@ -135,28 +140,84 @@  static int qemu_rbd_parsename(const char *filename,
 
     buf = qemu_strdup(start);
     p = buf;
+    *snap = '\0';
+    *conf = '\0';
 
     ret = qemu_rbd_next_tok(pool, pool_len, p, '/', "pool name", &p);
     if (ret < 0 || !p) {
         ret = -EINVAL;
         goto done;
     }
-    ret = qemu_rbd_next_tok(name, name_len, p, '@', "object name", &p);
-    if (ret < 0) {
-        goto done;
+
+    if (strchr(p, '@')) {
+        ret = qemu_rbd_next_tok(name, name_len, p, '@', "object name", &p);
+        if (ret < 0) {
+            goto done;
+        }
+        ret = qemu_rbd_next_tok(snap, snap_len, p, ':', "snap name", &p);
+    } else {
+        ret = qemu_rbd_next_tok(name, name_len, p, ':', "object name", &p);
     }
-    if (!p) {
-        *snap = '\0';
+    if (ret < 0 || !p) {
         goto done;
     }
 
-    ret = qemu_rbd_next_tok(snap, snap_len, p, '\0', "snap name", &p);
+    ret = qemu_rbd_next_tok(conf, conf_len, p, '\0', "configuration", &p);
 
 done:
     qemu_free(buf);
     return ret;
 }
 
+static int qemu_rbd_set_conf(rados_t cluster, const char *conf)
+{
+    char *p, *buf;
+    char name[RBD_MAX_CONF_NAME_SIZE];
+    char value[RBD_MAX_CONF_VAL_SIZE];
+    int ret = 0;
+
+    buf = qemu_strdup(conf);
+    p = buf;
+
+    while (p) {
+        ret = qemu_rbd_next_tok(name, sizeof(name), p,
+                                '=', "conf option name", &p);
+        if (ret < 0) {
+            break;
+        }
+
+        if (!p) {
+            error_report("conf option %s has no value", name);
+            ret = -EINVAL;
+            break;
+        }
+
+        ret = qemu_rbd_next_tok(value, sizeof(value), p,
+                                ':', "conf option value", &p);
+        if (ret < 0) {
+            break;
+        }
+
+        if (strcmp(name, "conf")) {
+            ret = rados_conf_set(cluster, name, value);
+            if (ret < 0) {
+                error_report("invalid conf option %s", name);
+                ret = -EINVAL;
+                break;
+            }
+        } else {
+            ret = rados_conf_read_file(cluster, value);
+            if (ret < 0) {
+                error_report("error reading conf file %s", value);
+                break;
+            }
+        }
+    }
+
+    qemu_free(buf);
+    return ret;
+}
+
 static int qemu_rbd_create(const char *filename, QEMUOptionParameter *options)
 {
     int64_t bytes = 0;
@@ -165,6 +226,7 @@  static int qemu_rbd_create(const char *filename, QEMUOptionParameter *options)
     char pool[RBD_MAX_POOL_NAME_SIZE];
     char name[RBD_MAX_IMAGE_NAME_SIZE];
     char snap_buf[RBD_MAX_SNAP_NAME_SIZE];
+    char conf[RBD_MAX_CONF_SIZE];
     char *snap = NULL;
     rados_t cluster;
     rados_ioctx_t io_ctx;
@@ -172,7 +234,8 @@  static int qemu_rbd_create(const char *filename, QEMUOptionParameter *options)
 
     if (qemu_rbd_parsename(filename, pool, sizeof(pool),
                            snap_buf, sizeof(snap_buf),
-                           name, sizeof(name)) < 0) {
+                           name, sizeof(name),
+                           conf, sizeof(conf)) < 0) {
         return -EINVAL;
     }
     if (snap_buf[0] != '\0') {
@@ -205,8 +268,17 @@  static int qemu_rbd_create(const char *filename, QEMUOptionParameter *options)
         return -EIO;
     }
 
-    if (rados_conf_read_file(cluster, NULL) < 0) {
-        error_report("error reading config file");
+    if (strstr(conf, "conf=") == NULL) {
+        if (rados_conf_read_file(cluster, NULL) < 0) {
+            error_report("error reading config file");
+            rados_shutdown(cluster);
+            return -EIO;
+        }
+    }
+
+    if (conf[0] != '\0' &&
+        qemu_rbd_set_conf(cluster, conf) < 0) {
+        error_report("error setting config options");
         rados_shutdown(cluster);
         return -EIO;
     }
@@ -316,11 +388,13 @@  static int qemu_rbd_open(BlockDriverState *bs, const char *filename, int flags)
     BDRVRBDState *s = bs->opaque;
     char pool[RBD_MAX_POOL_NAME_SIZE];
     char snap_buf[RBD_MAX_SNAP_NAME_SIZE];
+    char conf[RBD_MAX_CONF_SIZE];
     int r;
 
     if (qemu_rbd_parsename(filename, pool, sizeof(pool),
                            snap_buf, sizeof(snap_buf),
-                           s->name, sizeof(s->name)) < 0) {
+                           s->name, sizeof(s->name),
+                           conf, sizeof(conf)) < 0) {
         return -EINVAL;
     }
     s->snap = NULL;
@@ -334,11 +408,22 @@  static int qemu_rbd_open(BlockDriverState *bs, const char *filename, int flags)
         return r;
     }
 
-    r = rados_conf_read_file(s->cluster, NULL);
-    if (r < 0) {
-        error_report("error reading config file");
-        rados_shutdown(s->cluster);
-        return r;
+    if (strstr(conf, "conf=") == NULL) {
+        r = rados_conf_read_file(s->cluster, NULL);
+        if (r < 0) {
+            error_report("error reading config file");
+            rados_shutdown(s->cluster);
+            return r;
+        }
+    }
+
+    if (conf[0] != '\0') {
+        r = qemu_rbd_set_conf(s->cluster, conf);
+        if (r < 0) {
+            error_report("error setting config options");
+            rados_shutdown(s->cluster);
+            return r;
+        }
     }
 
     r = rados_connect(s->cluster);