block: Eliminate bdrv_iterate(), use bdrv_next()

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block-migration.c

@@ -343,12 +343,25 @@ static void unset_dirty_tracking(void)
     }
 }
 
-static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
+static void init_blk_migration(QEMUFile *f)
 {
+    BlockDriverState *bs;
     BlkMigDevState *bmds;
     int64_t sectors;
 
-    if (!bdrv_is_read_only(bs)) {
+    block_mig_state.submitted = 0;
+    block_mig_state.read_done = 0;
+    block_mig_state.transferred = 0;
+    block_mig_state.total_sector_sum = 0;
+    block_mig_state.prev_progress = -1;
+    block_mig_state.bulk_completed = 0;
+    block_mig_state.zero_blocks = migrate_zero_blocks();
+
+    for (bs = bdrv_next(NULL); bs; bs = bdrv_next(bs)) {
+        if (bdrv_is_read_only(bs)) {
+            continue;
+        }
+
         sectors = bdrv_nb_sectors(bs);
         if (sectors <= 0) {
             return;
@@ -378,19 +391,6 @@ static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
     }
 }
 
-static void init_blk_migration(QEMUFile *f)
-{
-    block_mig_state.submitted = 0;
-    block_mig_state.read_done = 0;
-    block_mig_state.transferred = 0;
-    block_mig_state.total_sector_sum = 0;
-    block_mig_state.prev_progress = -1;
-    block_mig_state.bulk_completed = 0;
-    block_mig_state.zero_blocks = migrate_zero_blocks();
-
-    bdrv_iterate(init_blk_migration_it, NULL);
-}
-
 /* Called with no lock taken.  */
 
 static int blk_mig_save_bulked_block(QEMUFile *f)

block.c

@@ -3906,15 +3906,6 @@ BlockDriverState *bdrv_next(BlockDriverState *bs)
     return QTAILQ_NEXT(bs, device_list);
 }
 
-void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
-{
-    BlockDriverState *bs;
-
-    QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
-        it(opaque, bs);
-    }
-}
-
 const char *bdrv_get_device_name(BlockDriverState *bs)
 {
     return bs->device_name;

blockdev.c

@@ -2608,26 +2608,21 @@ fail:
     qmp_output_visitor_cleanup(ov);
 }
 
-static void do_qmp_query_block_jobs_one(void *opaque, BlockDriverState *bs)
-{
-    BlockJobInfoList **prev = opaque;
-    BlockJob *job = bs->job;
-
-    if (job) {
-        BlockJobInfoList *elem = g_new0(BlockJobInfoList, 1);
-        elem->value = block_job_query(bs->job);
-        (*prev)->next = elem;
-        *prev = elem;
-    }
-}
-
 BlockJobInfoList *qmp_query_block_jobs(Error **errp)
 {
-    /* Dummy is a fake list element for holding the head pointer */
-    BlockJobInfoList dummy = {};
-    BlockJobInfoList *prev = &dummy;
-    bdrv_iterate(do_qmp_query_block_jobs_one, &prev);
-    return dummy.next;
+    BlockJobInfoList *head = NULL, **p_next = &head;
+    BlockDriverState *bs;
+
+    for (bs = bdrv_next(NULL); bs; bs = bdrv_next(bs)) {
+        if (bs->job) {
+            BlockJobInfoList *elem = g_new0(BlockJobInfoList, 1);
+            elem->value = block_job_query(bs->job);
+            *p_next = elem;
+            p_next = &elem->next;
+        }
+    }
+
+    return head;
 }
 
 QemuOptsList qemu_common_drive_opts = {

include/block/block.h

@@ -411,8 +411,6 @@ BlockDriverState *bdrv_lookup_bs(const char *device,
                                  Error **errp);
 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base);
 BlockDriverState *bdrv_next(BlockDriverState *bs);
-void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs),
-                  void *opaque);
 int bdrv_is_encrypted(BlockDriverState *bs);
 int bdrv_key_required(BlockDriverState *bs);
 int bdrv_set_key(BlockDriverState *bs, const char *key);

monitor.c

@@ -4216,24 +4216,6 @@ static void file_completion(Monitor *mon, const char *input)
     closedir(ffs);
 }
 
-typedef struct MonitorBlockComplete {
-    Monitor *mon;
-    const char *input;
-} MonitorBlockComplete;
-
-static void block_completion_it(void *opaque, BlockDriverState *bs)
-{
-    const char *name = bdrv_get_device_name(bs);
-    MonitorBlockComplete *mbc = opaque;
-    Monitor *mon = mbc->mon;
-    const char *input = mbc->input;
-
-    if (input[0] == '\0' ||
-        !strncmp(name, (char *)input, strlen(input))) {
-        readline_add_completion(mon->rs, name);
-    }
-}
-
 static const char *next_arg_type(const char *typestr)
 {
     const char *p = strchr(typestr, ':');
@@ -4671,9 +4653,9 @@ static void monitor_find_completion_by_table(Monitor *mon,
 {
     const char *cmdname;
     int i;
-    const char *ptype, *str;
+    const char *ptype, *str, *name;
     const mon_cmd_t *cmd;
-    MonitorBlockComplete mbs;
+    BlockDriverState *bs;
 
     if (nb_args <= 1) {
         /* command completion */
@@ -4725,10 +4707,14 @@ static void monitor_find_completion_by_table(Monitor *mon,
             break;
         case 'B':
             /* block device name completion */
-            mbs.mon = mon;
-            mbs.input = str;
             readline_set_completion_index(mon->rs, strlen(str));
-            bdrv_iterate(block_completion_it, &mbs);
+            for (bs = bdrv_next(NULL); bs; bs = bdrv_next(bs)) {
+                name = bdrv_get_device_name(bs);
+                if (str[0] == '\0' ||
+                    !strncmp(name, str, strlen(str))) {
+                    readline_add_completion(mon->rs, name);
+                }
+            }
             break;
         case 's':
         case 'S':