[Qemu-devel] [PATCH RESEND 23/50] blockdev: Catch NULL BDS in block_set_io_throttle

[Max Reitz]

Split bdrv_find() into blk_by_name() and blk_bs() to separate the
"no medium inserted" case from the "device not found" case.

Signed-off-by: Max Reitz <mre...@redhat.com>
---
 blockdev.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/blockdev.c b/blockdev.c
index 5f7eef5..9801a7e 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1922,15 +1922,25 @@ void qmp_block_set_io_throttle(const char *device, 
int64_t bps, int64_t bps_rd,
                                int64_t iops_size, Error **errp)
 {
     ThrottleConfig cfg;
+    BlockBackend *blk;
     BlockDriverState *bs;
     AioContext *aio_context;
 
-    bs = bdrv_find(device);
-    if (!bs) {
+    blk = blk_by_name(device);
+    if (!blk) {
         error_set(errp, QERR_DEVICE_NOT_FOUND, device);
         return;
     }
 
+    aio_context = blk_get_aio_context(blk);
+    aio_context_acquire(aio_context);
+
+    bs = blk_bs(blk);
+    if (!bs) {
+        error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
+        goto out;
+    }
+
     memset(&cfg, 0, sizeof(cfg));
     cfg.buckets[THROTTLE_BPS_TOTAL].avg = bps;
     cfg.buckets[THROTTLE_BPS_READ].avg  = bps_rd;
@@ -1964,12 +1974,9 @@ void qmp_block_set_io_throttle(const char *device, 
int64_t bps, int64_t bps_rd,
     }
 
     if (!check_throttle_config(&cfg, errp)) {
-        return;
+        goto out;
     }
 
-    aio_context = bdrv_get_aio_context(bs);
-    aio_context_acquire(aio_context);
-
     if (!bs->io_limits_enabled && throttle_enabled(&cfg)) {
         bdrv_io_limits_enable(bs);
     } else if (bs->io_limits_enabled && !throttle_enabled(&cfg)) {
@@ -1980,6 +1987,7 @@ void qmp_block_set_io_throttle(const char *device, 
int64_t bps, int64_t bps_rd,
         bdrv_set_io_limits(bs, &cfg);
     }
 
+out:
     aio_context_release(aio_context);
 }
 
-- 
2.1.0