[Qemu-devel] [PATCH v2 0/3] Add bdrv_get_device_or_node_name()

[Qemu-devel] [PATCH v2 0/3] Add bdrv_get_device_or_node_name()

[Alberto Garcia]

Second version of the series.

v2:
- bdrv_get_device_or_node_name() includes a comment explaining its
  usage.
- The error messages have been updated to say 'node' instead of
  'device' where appropriate.
- The BLOCK_IMAGE_CORRUPTED event has a new 'node-name' field.

Regards,

Berto

Alberto Garcia (3):
  block: add bdrv_get_device_or_node_name()
  block: use bdrv_get_device_or_node_name() in error messages
  block: add 'node-name' field to BLOCK_IMAGE_CORRUPTED

 block.c                   | 30 ++++++++++++++++++++----------
 block/qcow.c              |  4 ++--
 block/qcow2.c             | 10 +++++++---
 block/qed.c               |  2 +-
 block/quorum.c            |  5 +----
 block/vdi.c               |  2 +-
 block/vhdx.c              |  2 +-
 block/vmdk.c              |  4 ++--
 block/vpc.c               |  2 +-
 block/vvfat.c             |  3 ++-
 blockdev.c                |  4 ++--
 docs/qmp/qmp-events.txt   | 16 +++++++++-------
 include/block/block.h     |  1 +
 include/qapi/qmp/qerror.h |  8 ++++----
 qapi/block-core.json      | 13 ++++++++-----
 15 files changed, 62 insertions(+), 44 deletions(-)

-- 
2.1.4

[Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Alberto Garcia]

This function gets the device name associated with a BlockDriverState,
or its node name if the device name is empty.

Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 block.c               | 9 +++++++++
 block/quorum.c        | 5 +----
 include/block/block.h | 1 +
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/block.c b/block.c
index 0fe97de..98b90b4 100644
--- a/block.c
+++ b/block.c
@@ -3920,6 +3920,15 @@ const char *bdrv_get_device_name(const BlockDriverState *bs)
     return bs->blk ? blk_name(bs->blk) : "";
 }
 
+/* This can be used to identify nodes that might not have a device
+ * name associated. Since node and device names live in the same
+ * namespace, the result is unambiguous. The exception is if both are
+ * absent, then this returns an empty (non-null) string. */
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
+{
+    return bs->blk ? blk_name(bs->blk) : bs->node_name;
+}
+
 int bdrv_get_flags(BlockDriverState *bs)
 {
     return bs->open_flags;
diff --git a/block/quorum.c b/block/quorum.c
index 437b122..f91ef75 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -226,10 +226,7 @@ static void quorum_report_bad(QuorumAIOCB *acb, char *node_name, int ret)
 
 static void quorum_report_failure(QuorumAIOCB *acb)
 {
-    const char *reference = bdrv_get_device_name(acb->common.bs)[0] ?
-                            bdrv_get_device_name(acb->common.bs) :
-                            acb->common.bs->node_name;
-
+    const char *reference = bdrv_get_device_or_node_name(acb->common.bs);
     qapi_event_send_quorum_failure(reference, acb->sector_num,
                                    acb->nb_sectors, &error_abort);
 }
diff --git a/include/block/block.h b/include/block/block.h
index 4c57d63..b285e0d 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -398,6 +398,7 @@ void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
                          void *opaque);
 const char *bdrv_get_node_name(const BlockDriverState *bs);
 const char *bdrv_get_device_name(const BlockDriverState *bs);
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
 int bdrv_get_flags(BlockDriverState *bs);
 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
                           const uint8_t *buf, int nb_sectors);
-- 
2.1.4

[Qemu-devel] [PATCH 2/3] block: use bdrv_get_device_or_node_name() in error messages

[Alberto Garcia]

There are several error messages that identify a BlockDriverState by
its device name. However those errors can be produced in nodes that
don't have a device name associated.

In those cases we should use bdrv_get_device_or_node_name() to fall
back to the node name and produce a more meaningful message. The
messages are also updated to use the more generic term 'node' instead
of 'device'.

Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 block.c                   | 21 +++++++++++----------
 block/qcow.c              |  4 ++--
 block/qcow2.c             |  2 +-
 block/qed.c               |  2 +-
 block/vdi.c               |  2 +-
 block/vhdx.c              |  2 +-
 block/vmdk.c              |  4 ++--
 block/vpc.c               |  2 +-
 block/vvfat.c             |  3 ++-
 blockdev.c                |  4 ++--
 include/qapi/qmp/qerror.h |  8 ++++----
 11 files changed, 28 insertions(+), 26 deletions(-)

diff --git a/block.c b/block.c
index 98b90b4..8247f0a 100644
--- a/block.c
+++ b/block.c
@@ -1224,8 +1224,8 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
         bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
     } else if (backing_hd) {
         error_setg(&bs->backing_blocker,
-                   "device is used as backing hd of '%s'",
-                   bdrv_get_device_name(bs));
+                   "node is used as backing hd of '%s'",
+                   bdrv_get_device_or_node_name(bs));
     }
 
     bs->backing_hd = backing_hd;
@@ -1812,8 +1812,8 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
      * to r/w */
     if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
         reopen_state->flags & BDRV_O_RDWR) {
-        error_set(errp, QERR_DEVICE_IS_READ_ONLY,
-                  bdrv_get_device_name(reopen_state->bs));
+        error_set(errp, QERR_NODE_IS_READ_ONLY,
+                  bdrv_get_device_or_node_name(reopen_state->bs));
         goto error;
     }
 
@@ -1840,7 +1840,8 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
         /* It is currently mandatory to have a bdrv_reopen_prepare()
          * handler for each supported drv. */
         error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-                  drv->format_name, bdrv_get_device_name(reopen_state->bs),
+                  drv->format_name,
+                  bdrv_get_device_or_node_name(reopen_state->bs),
                  "reopening of file");
         ret = -1;
         goto error;
@@ -3764,8 +3765,8 @@ void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp)
 {
     if (key) {
         if (!bdrv_is_encrypted(bs)) {
-            error_setg(errp, "Device '%s' is not encrypted",
-                      bdrv_get_device_name(bs));
+            error_setg(errp, "Node '%s' is not encrypted",
+                      bdrv_get_device_or_node_name(bs));
         } else if (bdrv_set_key(bs, key) < 0) {
             error_set(errp, QERR_INVALID_PASSWORD);
         }
@@ -3773,7 +3774,7 @@ void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp)
         if (bdrv_key_required(bs)) {
             error_set(errp, ERROR_CLASS_DEVICE_ENCRYPTED,
                       "'%s' (%s) is encrypted",
-                      bdrv_get_device_name(bs),
+                      bdrv_get_device_or_node_name(bs),
                       bdrv_get_encrypted_filename(bs));
         }
     }
@@ -5548,8 +5549,8 @@ bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp)
     if (!QLIST_EMPTY(&bs->op_blockers[op])) {
         blocker = QLIST_FIRST(&bs->op_blockers[op]);
         if (errp) {
-            error_setg(errp, "Device '%s' is busy: %s",
-                       bdrv_get_device_name(bs),
+            error_setg(errp, "Node '%s' is busy: %s",
+                       bdrv_get_device_or_node_name(bs),
                        error_get_pretty(blocker->reason));
         }
         return true;
diff --git a/block/qcow.c b/block/qcow.c
index 0558969..d4287ca 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -124,7 +124,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
         snprintf(version, sizeof(version), "QCOW version %" PRIu32,
                  header.version);
         error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
-                  bdrv_get_device_name(bs), "qcow", version);
+                  bdrv_get_device_or_node_name(bs), "qcow", version);
         ret = -ENOTSUP;
         goto fail;
     }
@@ -231,7 +231,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
     /* Disable migration when qcow images are used */
     error_set(&s->migration_blocker,
               QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-              "qcow", bdrv_get_device_name(bs), "live migration");
+              "qcow", bdrv_get_device_or_node_name(bs), "live migration");
     migrate_add_blocker(s->migration_blocker);
 
     qemu_co_mutex_init(&s->lock);
diff --git a/block/qcow2.c b/block/qcow2.c
index 32bdf75..168006b 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -207,7 +207,7 @@ static void GCC_FMT_ATTR(3, 4) report_unsupported(BlockDriverState *bs,
     va_end(ap);
 
     error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
-              bdrv_get_device_name(bs), "qcow2", msg);
+              bdrv_get_device_or_node_name(bs), "qcow2", msg);
 }
 
 static void report_unsupported_feature(BlockDriverState *bs,
diff --git a/block/qed.c b/block/qed.c
index 892b13c..7d32ce4 100644
--- a/block/qed.c
+++ b/block/qed.c
@@ -408,7 +408,7 @@ static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags,
         snprintf(buf, sizeof(buf), "%" PRIx64,
             s->header.features & ~QED_FEATURE_MASK);
         error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
-            bdrv_get_device_name(bs), "QED", buf);
+            bdrv_get_device_or_node_name(bs), "QED", buf);
         return -ENOTSUP;
     }
     if (!qed_is_cluster_size_valid(s->header.cluster_size)) {
diff --git a/block/vdi.c b/block/vdi.c
index 53bd02f..f0dc364 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -504,7 +504,7 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
     /* Disable migration when vdi images are used */
     error_set(&s->migration_blocker,
               QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-              "vdi", bdrv_get_device_name(bs), "live migration");
+              "vdi", bdrv_get_device_or_node_name(bs), "live migration");
     migrate_add_blocker(s->migration_blocker);
 
     qemu_co_mutex_init(&s->write_lock);
diff --git a/block/vhdx.c b/block/vhdx.c
index bb3ed45..d5dfe00 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -1004,7 +1004,7 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
     /* Disable migration when VHDX images are used */
     error_set(&s->migration_blocker,
             QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-            "vhdx", bdrv_get_device_name(bs), "live migration");
+            "vhdx", bdrv_get_device_or_node_name(bs), "live migration");
     migrate_add_blocker(s->migration_blocker);
 
     return 0;
diff --git a/block/vmdk.c b/block/vmdk.c
index 8410a15..0230070 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -669,7 +669,7 @@ static int vmdk_open_vmdk4(BlockDriverState *bs,
         snprintf(buf, sizeof(buf), "VMDK version %" PRId32,
                  le32_to_cpu(header.version));
         error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
-                  bdrv_get_device_name(bs), "vmdk", buf);
+                  bdrv_get_device_or_node_name(bs), "vmdk", buf);
         return -ENOTSUP;
     } else if (le32_to_cpu(header.version) == 3 && (flags & BDRV_O_RDWR)) {
         /* VMware KB 2064959 explains that version 3 added support for
@@ -964,7 +964,7 @@ static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
     /* Disable migration when VMDK images are used */
     error_set(&s->migration_blocker,
               QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-              "vmdk", bdrv_get_device_name(bs), "live migration");
+              "vmdk", bdrv_get_device_or_node_name(bs), "live migration");
     migrate_add_blocker(s->migration_blocker);
     g_free(buf);
     return 0;
diff --git a/block/vpc.c b/block/vpc.c
index 43e768e..fd418b9 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -320,7 +320,7 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
     /* Disable migration when VHD images are used */
     error_set(&s->migration_blocker,
               QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-              "vpc", bdrv_get_device_name(bs), "live migration");
+              "vpc", bdrv_get_device_or_node_name(bs), "live migration");
     migrate_add_blocker(s->migration_blocker);
 
     return 0;
diff --git a/block/vvfat.c b/block/vvfat.c
index 9be632f..9ed3291 100644
--- a/block/vvfat.c
+++ b/block/vvfat.c
@@ -1182,7 +1182,8 @@ static int vvfat_open(BlockDriverState *bs, QDict *options, int flags,
     if (s->qcow) {
         error_set(&s->migration_blocker,
                   QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-                  "vvfat (rw)", bdrv_get_device_name(bs), "live migration");
+                  "vvfat (rw)", bdrv_get_device_or_node_name(bs),
+                  "live migration");
         migrate_add_blocker(s->migration_blocker);
     }
 
diff --git a/blockdev.c b/blockdev.c
index 0b50985..f83b975 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1248,7 +1248,7 @@ static void internal_snapshot_prepare(BlkTransactionState *common,
     }
 
     if (bdrv_is_read_only(bs)) {
-        error_set(errp, QERR_DEVICE_IS_READ_ONLY, device);
+        error_set(errp, QERR_NODE_IS_READ_ONLY, device);
         return;
     }
 
@@ -2055,7 +2055,7 @@ void qmp_block_resize(bool has_device, const char *device,
         error_set(errp, QERR_UNSUPPORTED);
         break;
     case -EACCES:
-        error_set(errp, QERR_DEVICE_IS_READ_ONLY, device);
+        error_set(errp, QERR_NODE_IS_READ_ONLY, device);
         break;
     case -EBUSY:
         error_set(errp, QERR_DEVICE_IN_USE, device);
diff --git a/include/qapi/qmp/qerror.h b/include/qapi/qmp/qerror.h
index 57a62d4..46cad14 100644
--- a/include/qapi/qmp/qerror.h
+++ b/include/qapi/qmp/qerror.h
@@ -38,7 +38,7 @@ void qerror_report_err(Error *err);
     ERROR_CLASS_GENERIC_ERROR, "Base '%s' not found"
 
 #define QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED \
-    ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by device '%s' does not support feature '%s'"
+    ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by node '%s' does not support feature '%s'"
 
 #define QERR_BLOCK_JOB_NOT_READY \
     ERROR_CLASS_GENERIC_ERROR, "The active block job for device '%s' cannot be completed"
@@ -58,9 +58,6 @@ void qerror_report_err(Error *err);
 #define QERR_DEVICE_IN_USE \
     ERROR_CLASS_GENERIC_ERROR, "Device '%s' is in use"
 
-#define QERR_DEVICE_IS_READ_ONLY \
-    ERROR_CLASS_GENERIC_ERROR, "Device '%s' is read only"
-
 #define QERR_DEVICE_NO_HOTPLUG \
     ERROR_CLASS_GENERIC_ERROR, "Device '%s' does not support hotplugging"
 
@@ -103,6 +100,9 @@ void qerror_report_err(Error *err);
 #define QERR_MISSING_PARAMETER \
     ERROR_CLASS_GENERIC_ERROR, "Parameter '%s' is missing"
 
+#define QERR_NODE_IS_READ_ONLY \
+    ERROR_CLASS_GENERIC_ERROR, "Node '%s' is read only"
+
 #define QERR_PERMISSION_DENIED \
     ERROR_CLASS_GENERIC_ERROR, "Insufficient permission to perform this operation"
 
-- 
2.1.4

[Qemu-devel] [PATCH 3/3] block: add 'node-name' field to BLOCK_IMAGE_CORRUPTED

[Alberto Garcia]

Since this event can occur in nodes that cannot have a device name
associated, include also a field with the node name.

Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 block/qcow2.c           |  8 ++++++--
 docs/qmp/qmp-events.txt | 16 +++++++++-------
 qapi/block-core.json    | 13 ++++++++-----
 3 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/block/qcow2.c b/block/qcow2.c
index 168006b..e7c78f1 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2809,6 +2809,7 @@ void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
                              int64_t size, const char *message_format, ...)
 {
     BDRVQcowState *s = bs->opaque;
+    const char *node_name;
     char *message;
     va_list ap;
 
@@ -2832,8 +2833,11 @@ void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
                 "corruption events will be suppressed\n", message);
     }
 
-    qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs), message,
-                                          offset >= 0, offset, size >= 0, size,
+    node_name = bdrv_get_node_name(bs);
+    qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs),
+                                          *node_name != '\0', node_name,
+                                          message, offset >= 0, offset,
+                                          size >= 0, size,
                                           fatal, &error_abort);
     g_free(message);
 
diff --git a/docs/qmp/qmp-events.txt b/docs/qmp/qmp-events.txt
index d759d19..ed1d0a5 100644
--- a/docs/qmp/qmp-events.txt
+++ b/docs/qmp/qmp-events.txt
@@ -35,17 +35,19 @@ Emitted when a disk image is being marked corrupt.
 
 Data:
 
-- "device": Device name (json-string)
-- "msg":    Informative message (e.g., reason for the corruption) (json-string)
-- "offset": If the corruption resulted from an image access, this is the access
-            offset into the image (json-int)
-- "size":   If the corruption resulted from an image access, this is the access
-            size (json-int)
+- "device":    Device name (json-string)
+- "node-name": Node name, if it's present (json-string)
+- "msg":       Informative message (e.g., reason for the corruption)
+               (json-string)
+- "offset":    If the corruption resulted from an image access, this
+               is the access offset into the image (json-int)
+- "size":      If the corruption resulted from an image access, this
+               is the access size (json-int)
 
 Example:
 
 { "event": "BLOCK_IMAGE_CORRUPTED",
-    "data": { "device": "ide0-hd0",
+    "data": { "device": "ide0-hd0", "node-name": "node0",
         "msg": "Prevented active L1 table overwrite", "offset": 196608,
         "size": 65536 },
     "timestamp": { "seconds": 1378126126, "microseconds": 966463 } }
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 42c8850..e650168 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1753,6 +1753,8 @@
 #
 # @device: device name
 #
+# @node-name: #optional node name (Since: 2.3)
+#
 # @msg: informative message for human consumption, such as the kind of
 #       corruption being detected. It should not be parsed by machine as it is
 #       not guaranteed to be stable
@@ -1770,11 +1772,12 @@
 # Since: 1.7
 ##
 { 'event': 'BLOCK_IMAGE_CORRUPTED',
-  'data': { 'device' : 'str',
-            'msg'    : 'str',
-            '*offset': 'int',
-            '*size'  : 'int',
-            'fatal'  : 'bool' } }
+  'data': { 'device'     : 'str',
+            '*node-name' : 'str',
+            'msg'        : 'str',
+            '*offset'    : 'int',
+            '*size'      : 'int',
+            'fatal'      : 'bool' } }
 
 ##
 # @BLOCK_IO_ERROR
-- 
2.1.4

Re: [Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Max Reitz]

On 2015-03-20 at 06:19, Alberto Garcia wrote:
> This function gets the device name associated with a BlockDriverState,
> or its node name if the device name is empty.
>
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> ---
>   block.c               | 9 +++++++++
>   block/quorum.c        | 5 +----
>   include/block/block.h | 1 +
>   3 files changed, 11 insertions(+), 4 deletions(-)

Reviewed-by: Max Reitz <mreitz@redhat.com>

Re: [Qemu-devel] [PATCH 2/3] block: use bdrv_get_device_or_node_name() in error messages

[Max Reitz]

On 2015-03-20 at 06:19, Alberto Garcia wrote:
> There are several error messages that identify a BlockDriverState by
> its device name. However those errors can be produced in nodes that
> don't have a device name associated.
>
> In those cases we should use bdrv_get_device_or_node_name() to fall
> back to the node name and produce a more meaningful message. The
> messages are also updated to use the more generic term 'node' instead
> of 'device'.
>
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> ---
>   block.c                   | 21 +++++++++++----------
>   block/qcow.c              |  4 ++--
>   block/qcow2.c             |  2 +-
>   block/qed.c               |  2 +-
>   block/vdi.c               |  2 +-
>   block/vhdx.c              |  2 +-
>   block/vmdk.c              |  4 ++--
>   block/vpc.c               |  2 +-
>   block/vvfat.c             |  3 ++-
>   blockdev.c                |  4 ++--
>   include/qapi/qmp/qerror.h |  8 ++++----
>   11 files changed, 28 insertions(+), 26 deletions(-)
>
> diff --git a/block.c b/block.c
> index 98b90b4..8247f0a 100644
> --- a/block.c
> +++ b/block.c
> @@ -1224,8 +1224,8 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
>           bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
>       } else if (backing_hd) {
>           error_setg(&bs->backing_blocker,
> -                   "device is used as backing hd of '%s'",
> -                   bdrv_get_device_name(bs));
> +                   "node is used as backing hd of '%s'",
> +                   bdrv_get_device_or_node_name(bs));

Actually, the change of "device" to "node" here is independent of the 
use of bdrv_get_device_or_node_name(). But it's correct anyway.

>       }
>   
>       bs->backing_hd = backing_hd;
> @@ -1812,8 +1812,8 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
>        * to r/w */
>       if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
>           reopen_state->flags & BDRV_O_RDWR) {
> -        error_set(errp, QERR_DEVICE_IS_READ_ONLY,
> -                  bdrv_get_device_name(reopen_state->bs));
> +        error_set(errp, QERR_NODE_IS_READ_ONLY,
> +                  bdrv_get_device_or_node_name(reopen_state->bs));

I think Markus would be happier with just removing the macro.

(Make it error_setg(errp, "Node '%s' is read only", 
bdrv_get_device_or_node_name(reopen_state->bs)) and remove the 
QERR_DEVICE_IS_READ_ONLY macro from qerror.h)

[snip]

> diff --git a/include/qapi/qmp/qerror.h b/include/qapi/qmp/qerror.h
> index 57a62d4..46cad14 100644
> --- a/include/qapi/qmp/qerror.h
> +++ b/include/qapi/qmp/qerror.h
> @@ -38,7 +38,7 @@ void qerror_report_err(Error *err);
>       ERROR_CLASS_GENERIC_ERROR, "Base '%s' not found"
>   
>   #define QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED \
> -    ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by device '%s' does not support feature '%s'"
> +    ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by node '%s' does not support feature '%s'"

Preexisting, but first: This line has over 80 characters.

Second: This seems like a good opportunity to drop this macro and 
replace its occurrences by error_setg(errp, "Block format...") and the like.

>    #define QERR_BLOCK_JOB_NOT_READY \
>       ERROR_CLASS_GENERIC_ERROR, "The active block job for device '%s' cannot be completed"
> @@ -58,9 +58,6 @@ void qerror_report_err(Error *err);
>   #define QERR_DEVICE_IN_USE \
>       ERROR_CLASS_GENERIC_ERROR, "Device '%s' is in use"
>   
> -#define QERR_DEVICE_IS_READ_ONLY \
> -    ERROR_CLASS_GENERIC_ERROR, "Device '%s' is read only"
> -
>   #define QERR_DEVICE_NO_HOTPLUG \
>       ERROR_CLASS_GENERIC_ERROR, "Device '%s' does not support hotplugging"
>   
> @@ -103,6 +100,9 @@ void qerror_report_err(Error *err);
>   #define QERR_MISSING_PARAMETER \
>       ERROR_CLASS_GENERIC_ERROR, "Parameter '%s' is missing"
>   
> +#define QERR_NODE_IS_READ_ONLY \
> +    ERROR_CLASS_GENERIC_ERROR, "Node '%s' is read only"
> +
>   #define QERR_PERMISSION_DENIED \
>       ERROR_CLASS_GENERIC_ERROR, "Insufficient permission to perform this operation"

As said above, the same goes for this macro.

I'm not so ardent about this, so if you want to keep the macros, it's 
fine with me; but the overly long line need to be fixed (only the one 
you're touching, not necessarily the rest, because I guess they'll be 
dropped in the future anyway).

Markus?

Max

Re: [Qemu-devel] [PATCH 3/3] block: add 'node-name' field to BLOCK_IMAGE_CORRUPTED

[Max Reitz]

On 2015-03-20 at 06:19, Alberto Garcia wrote:
> Since this event can occur in nodes that cannot have a device name
> associated, include also a field with the node name.
>
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> ---
>   block/qcow2.c           |  8 ++++++--
>   docs/qmp/qmp-events.txt | 16 +++++++++-------
>   qapi/block-core.json    | 13 ++++++++-----
>   3 files changed, 23 insertions(+), 14 deletions(-)
>
> diff --git a/block/qcow2.c b/block/qcow2.c
> index 168006b..e7c78f1 100644
> --- a/block/qcow2.c
> +++ b/block/qcow2.c
> @@ -2809,6 +2809,7 @@ void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
>                                int64_t size, const char *message_format, ...)
>   {
>       BDRVQcowState *s = bs->opaque;
> +    const char *node_name;
>       char *message;
>       va_list ap;
>   
> @@ -2832,8 +2833,11 @@ void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
>                   "corruption events will be suppressed\n", message);
>       }
>   
> -    qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs), message,
> -                                          offset >= 0, offset, size >= 0, size,
> +    node_name = bdrv_get_node_name(bs);
> +    qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs),
> +                                          *node_name != '\0', node_name,
> +                                          message, offset >= 0, offset,
> +                                          size >= 0, size,
>                                             fatal, &error_abort);
>       g_free(message);
>   
> diff --git a/docs/qmp/qmp-events.txt b/docs/qmp/qmp-events.txt
> index d759d19..ed1d0a5 100644
> --- a/docs/qmp/qmp-events.txt
> +++ b/docs/qmp/qmp-events.txt
> @@ -35,17 +35,19 @@ Emitted when a disk image is being marked corrupt.
>   
>   Data:
>   
> -- "device": Device name (json-string)
> -- "msg":    Informative message (e.g., reason for the corruption) (json-string)
> -- "offset": If the corruption resulted from an image access, this is the access
> -            offset into the image (json-int)
> -- "size":   If the corruption resulted from an image access, this is the access
> -            size (json-int)
> +- "device":    Device name (json-string)
> +- "node-name": Node name, if it's present (json-string)
> +- "msg":       Informative message (e.g., reason for the corruption)
> +               (json-string)
> +- "offset":    If the corruption resulted from an image access, this
> +               is the access offset into the image (json-int)
> +- "size":      If the corruption resulted from an image access, this
> +               is the access size (json-int)
>   
>   Example:
>   
>   { "event": "BLOCK_IMAGE_CORRUPTED",
> -    "data": { "device": "ide0-hd0",
> +    "data": { "device": "ide0-hd0", "node-name": "node0",
>           "msg": "Prevented active L1 table overwrite", "offset": 196608,
>           "size": 65536 },
>       "timestamp": { "seconds": 1378126126, "microseconds": 966463 } }
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index 42c8850..e650168 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -1753,6 +1753,8 @@
>   #
>   # @device: device name
>   #
> +# @node-name: #optional node name (Since: 2.3)

*2.4

With that fixed:

Reviewed-by: Max Reitz <mreitz@redhat.com>

> +#
>   # @msg: informative message for human consumption, such as the kind of
>   #       corruption being detected. It should not be parsed by machine as it is
>   #       not guaranteed to be stable
> @@ -1770,11 +1772,12 @@
>   # Since: 1.7
>   ##
>   { 'event': 'BLOCK_IMAGE_CORRUPTED',
> -  'data': { 'device' : 'str',
> -            'msg'    : 'str',
> -            '*offset': 'int',
> -            '*size'  : 'int',
> -            'fatal'  : 'bool' } }
> +  'data': { 'device'     : 'str',
> +            '*node-name' : 'str',
> +            'msg'        : 'str',
> +            '*offset'    : 'int',
> +            '*size'      : 'int',
> +            'fatal'      : 'bool' } }
>   
>   ##
>   # @BLOCK_IO_ERROR

Re: [Qemu-devel] [PATCH 2/3] block: use bdrv_get_device_or_node_name() in error messages

[Markus Armbruster]

Max Reitz <mreitz@redhat.com> writes:

> On 2015-03-20 at 06:19, Alberto Garcia wrote:
>> There are several error messages that identify a BlockDriverState by
>> its device name. However those errors can be produced in nodes that
>> don't have a device name associated.
>>
>> In those cases we should use bdrv_get_device_or_node_name() to fall
>> back to the node name and produce a more meaningful message. The
>> messages are also updated to use the more generic term 'node' instead
>> of 'device'.
>>
>> Signed-off-by: Alberto Garcia <berto@igalia.com>
>> ---
>>   block.c                   | 21 +++++++++++----------
>>   block/qcow.c              |  4 ++--
>>   block/qcow2.c             |  2 +-
>>   block/qed.c               |  2 +-
>>   block/vdi.c               |  2 +-
>>   block/vhdx.c              |  2 +-
>>   block/vmdk.c              |  4 ++--
>>   block/vpc.c               |  2 +-
>>   block/vvfat.c             |  3 ++-
>>   blockdev.c                |  4 ++--
>>   include/qapi/qmp/qerror.h |  8 ++++----
>>   11 files changed, 28 insertions(+), 26 deletions(-)
>>
>> diff --git a/block.c b/block.c
>> index 98b90b4..8247f0a 100644
>> --- a/block.c
>> +++ b/block.c
>> @@ -1224,8 +1224,8 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
>>           bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
>>       } else if (backing_hd) {
>>           error_setg(&bs->backing_blocker,
>> -                   "device is used as backing hd of '%s'",
>> -                   bdrv_get_device_name(bs));
>> +                   "node is used as backing hd of '%s'",
>> +                   bdrv_get_device_or_node_name(bs));
>
> Actually, the change of "device" to "node" here is independent of the
> use of bdrv_get_device_or_node_name(). But it's correct anyway.
>
>>       }
>>         bs->backing_hd = backing_hd;
>> @@ -1812,8 +1812,8 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
>>        * to r/w */
>>       if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
>>           reopen_state->flags & BDRV_O_RDWR) {
>> -        error_set(errp, QERR_DEVICE_IS_READ_ONLY,
>> -                  bdrv_get_device_name(reopen_state->bs));
>> +        error_set(errp, QERR_NODE_IS_READ_ONLY,
>> +                  bdrv_get_device_or_node_name(reopen_state->bs));
>
> I think Markus would be happier with just removing the macro.
>
> (Make it error_setg(errp, "Node '%s' is read only",
> bdrv_get_device_or_node_name(reopen_state->bs)) and remove the
> QERR_DEVICE_IS_READ_ONLY macro from qerror.h)
>
> [snip]
>
>> diff --git a/include/qapi/qmp/qerror.h b/include/qapi/qmp/qerror.h
>> index 57a62d4..46cad14 100644
>> --- a/include/qapi/qmp/qerror.h
>> +++ b/include/qapi/qmp/qerror.h
>> @@ -38,7 +38,7 @@ void qerror_report_err(Error *err);
>>       ERROR_CLASS_GENERIC_ERROR, "Base '%s' not found"
>>     #define QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED \
>> -    ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by device '%s' does not support feature '%s'"
>> +    ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by node '%s' does not support feature '%s'"
>
> Preexisting, but first: This line has over 80 characters.
>
> Second: This seems like a good opportunity to drop this macro and
> replace its occurrences by error_setg(errp, "Block format...") and the
> like.
>
>>    #define QERR_BLOCK_JOB_NOT_READY \
>>       ERROR_CLASS_GENERIC_ERROR, "The active block job for device '%s' cannot be completed"
>> @@ -58,9 +58,6 @@ void qerror_report_err(Error *err);
>>   #define QERR_DEVICE_IN_USE \
>>       ERROR_CLASS_GENERIC_ERROR, "Device '%s' is in use"
>>   -#define QERR_DEVICE_IS_READ_ONLY \
>> -    ERROR_CLASS_GENERIC_ERROR, "Device '%s' is read only"
>> -
>>   #define QERR_DEVICE_NO_HOTPLUG \
>>       ERROR_CLASS_GENERIC_ERROR, "Device '%s' does not support hotplugging"
>>   @@ -103,6 +100,9 @@ void qerror_report_err(Error *err);
>>   #define QERR_MISSING_PARAMETER \
>>       ERROR_CLASS_GENERIC_ERROR, "Parameter '%s' is missing"
>>   +#define QERR_NODE_IS_READ_ONLY \
>> +    ERROR_CLASS_GENERIC_ERROR, "Node '%s' is read only"
>> +
>>   #define QERR_PERMISSION_DENIED \
>>       ERROR_CLASS_GENERIC_ERROR, "Insufficient permission to perform this operation"
>
> As said above, the same goes for this macro.
>
> I'm not so ardent about this, so if you want to keep the macros, it's
> fine with me; but the overly long line need to be fixed (only the one
> you're touching, not necessarily the rest, because I guess they'll be
> dropped in the future anyway).
>
> Markus?

I've been chipping away at qerror.h for a while.  I think I can empty it
out in the next development cycle.  So every new QERR_ macro you add
I'll have to replace again.  Using literal strings instead will save me
the trouble.

If you find yourself using the same error string in many places, chances
are that some of these places do the same thing.  Consider factoring
out.

Other than that, I wouldn't worry about duplicating error strings.  Drop
in the bucket.

Re: [Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 1447 bytes --]

On 04/08/2015 03:29 AM, Alberto Garcia wrote:
> This function gets the device name associated with a BlockDriverState,
> or its node name if the device name is empty.
> 
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
>  block.c               | 9 +++++++++
>  block/quorum.c        | 5 +----
>  include/block/block.h | 1 +
>  3 files changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/block.c b/block.c
> index f2f8ae7..24adfc1 100644
> --- a/block.c
> +++ b/block.c
> @@ -3953,6 +3953,15 @@ const char *bdrv_get_device_name(const BlockDriverState *bs)
>      return bs->blk ? blk_name(bs->blk) : "";
>  }
>  
> +/* This can be used to identify nodes that might not have a device
> + * name associated. Since node and device names live in the same
> + * namespace, the result is unambiguous. The exception is if both are
> + * absent, then this returns an empty (non-null) string. */
> +const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
> +{
> +    return bs->blk ? blk_name(bs->blk) : bs->node_name;

I had to check; bs->node_name is an array rather than a pointer, so it
always contains a non-null string (whether or not it is the empty
string), so your comment is correct.

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
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[Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Alberto Garcia]

This function gets the device name associated with a BlockDriverState,
or its node name if the device name is empty.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block.c               | 9 +++++++++
 block/quorum.c        | 5 +----
 include/block/block.h | 1 +
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/block.c b/block.c
index f2f8ae7..24adfc1 100644
--- a/block.c
+++ b/block.c
@@ -3953,6 +3953,15 @@ const char *bdrv_get_device_name(const BlockDriverState *bs)
     return bs->blk ? blk_name(bs->blk) : "";
 }
 
+/* This can be used to identify nodes that might not have a device
+ * name associated. Since node and device names live in the same
+ * namespace, the result is unambiguous. The exception is if both are
+ * absent, then this returns an empty (non-null) string. */
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
+{
+    return bs->blk ? blk_name(bs->blk) : bs->node_name;
+}
+
 int bdrv_get_flags(BlockDriverState *bs)
 {
     return bs->open_flags;
diff --git a/block/quorum.c b/block/quorum.c
index 437b122..f91ef75 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -226,10 +226,7 @@ static void quorum_report_bad(QuorumAIOCB *acb, char *node_name, int ret)
 
 static void quorum_report_failure(QuorumAIOCB *acb)
 {
-    const char *reference = bdrv_get_device_name(acb->common.bs)[0] ?
-                            bdrv_get_device_name(acb->common.bs) :
-                            acb->common.bs->node_name;
-
+    const char *reference = bdrv_get_device_or_node_name(acb->common.bs);
     qapi_event_send_quorum_failure(reference, acb->sector_num,
                                    acb->nb_sectors, &error_abort);
 }
diff --git a/include/block/block.h b/include/block/block.h
index 4c57d63..b285e0d 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -398,6 +398,7 @@ void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
                          void *opaque);
 const char *bdrv_get_node_name(const BlockDriverState *bs);
 const char *bdrv_get_device_name(const BlockDriverState *bs);
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
 int bdrv_get_flags(BlockDriverState *bs);
 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
                           const uint8_t *buf, int nb_sectors);
-- 
2.1.4

Re: [Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Max Reitz]

On 2015-03-20 at 10:33, Alberto Garcia wrote:
> This function gets the device name associated with a BlockDriverState,
> or its node name if the device name is empty.
>
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> ---
>   block.c               | 9 +++++++++
>   block/quorum.c        | 5 +----
>   include/block/block.h | 1 +
>   3 files changed, 11 insertions(+), 4 deletions(-)

No changes from v2, so:

Reviewed-by: Max Reitz <mreitz@redhat.com>

(Feel free to put these R-b lines into the commit message under your 
S-o-b for patches that got a R-b and don't have any changes)

[Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Alberto Garcia]

This function gets the device name associated with a BlockDriverState,
or its node name if the device name is empty.

Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 block.c               | 9 +++++++++
 block/quorum.c        | 5 +----
 include/block/block.h | 1 +
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/block.c b/block.c
index 0fe97de..98b90b4 100644
--- a/block.c
+++ b/block.c
@@ -3920,6 +3920,15 @@ const char *bdrv_get_device_name(const BlockDriverState *bs)
     return bs->blk ? blk_name(bs->blk) : "";
 }
 
+/* This can be used to identify nodes that might not have a device
+ * name associated. Since node and device names live in the same
+ * namespace, the result is unambiguous. The exception is if both are
+ * absent, then this returns an empty (non-null) string. */
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
+{
+    return bs->blk ? blk_name(bs->blk) : bs->node_name;
+}
+
 int bdrv_get_flags(BlockDriverState *bs)
 {
     return bs->open_flags;
diff --git a/block/quorum.c b/block/quorum.c
index 437b122..f91ef75 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -226,10 +226,7 @@ static void quorum_report_bad(QuorumAIOCB *acb, char *node_name, int ret)
 
 static void quorum_report_failure(QuorumAIOCB *acb)
 {
-    const char *reference = bdrv_get_device_name(acb->common.bs)[0] ?
-                            bdrv_get_device_name(acb->common.bs) :
-                            acb->common.bs->node_name;
-
+    const char *reference = bdrv_get_device_or_node_name(acb->common.bs);
     qapi_event_send_quorum_failure(reference, acb->sector_num,
                                    acb->nb_sectors, &error_abort);
 }
diff --git a/include/block/block.h b/include/block/block.h
index 4c57d63..b285e0d 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -398,6 +398,7 @@ void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
                          void *opaque);
 const char *bdrv_get_node_name(const BlockDriverState *bs);
 const char *bdrv_get_device_name(const BlockDriverState *bs);
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
 int bdrv_get_flags(BlockDriverState *bs);
 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
                           const uint8_t *buf, int nb_sectors);
-- 
2.1.4

Re: [Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Markus Armbruster]

Alberto Garcia <berto@igalia.com> writes:

> On Fri, Mar 20, 2015 at 08:40:32AM +0100, Markus Armbruster wrote:
>
>> > +const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
>> > +{
>> > +    return bs->blk ? blk_name(bs->blk) : bs->node_name;
>> > +}
>> > +
>> 
>> Does this have uses beyond identifying @bs to the user?
>
> None that I can think of, although apart from error messages it can
> also be used in data types, like the cases of BLOCK_IMAGE_CORRUPTED
> and BlockJobInfo that are being discussed:
>
>    https://lists.gnu.org/archive/html/qemu-devel/2015-03/msg03651.html

Workable because BB and BDS names share a common name space.  But is it
a good idea?  No need to discuss this here if it's already discussed
elsewhere.

>> >  static void quorum_report_failure(QuorumAIOCB *acb)
>> >  {
>> > -    const char *reference = bdrv_get_device_name(acb->common.bs)[0] ?
>> > -                            bdrv_get_device_name(acb->common.bs) :
>> > -                            acb->common.bs->node_name;
>> > -
>> > +    const char *reference = bdrv_get_device_or_node_name(acb->common.bs);
>> >      qapi_event_send_quorum_failure(reference, acb->sector_num,
>> >                                     acb->nb_sectors, &error_abort);
>> >  }
>> 
>> Preexisting: what if reference is null?
>
> It can't happen, both the device and the node name strings are
> guaranteed to be non-null. The latter is actually a static string so
> there's no chance bs->node_name returns a null pointer.

You're right, I missed the fact that BDS member node_name is an array.

Suggest to add a function comment to bdrv_get_device_or_node_name()
explaining intended use, and that it never returns null.

Re: [Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Alberto Garcia]

On Fri, Mar 20, 2015 at 08:40:32AM +0100, Markus Armbruster wrote:

> > +const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
> > +{
> > +    return bs->blk ? blk_name(bs->blk) : bs->node_name;
> > +}
> > +
> 
> Does this have uses beyond identifying @bs to the user?

None that I can think of, although apart from error messages it can
also be used in data types, like the cases of BLOCK_IMAGE_CORRUPTED
and BlockJobInfo that are being discussed:

   https://lists.gnu.org/archive/html/qemu-devel/2015-03/msg03651.html

> >  static void quorum_report_failure(QuorumAIOCB *acb)
> >  {
> > -    const char *reference = bdrv_get_device_name(acb->common.bs)[0] ?
> > -                            bdrv_get_device_name(acb->common.bs) :
> > -                            acb->common.bs->node_name;
> > -
> > +    const char *reference = bdrv_get_device_or_node_name(acb->common.bs);
> >      qapi_event_send_quorum_failure(reference, acb->sector_num,
> >                                     acb->nb_sectors, &error_abort);
> >  }
> 
> Preexisting: what if reference is null?

It can't happen, both the device and the node name strings are
guaranteed to be non-null. The latter is actually a static string so
there's no chance bs->node_name returns a null pointer.

Berto

Re: [Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Markus Armbruster]

Alberto Garcia <berto@igalia.com> writes:

> This function gets the device name associated with a BlockDriverState,
> or its node name if the device name is empty.
>
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> ---
>  block.c               | 5 +++++
>  block/quorum.c        | 5 +----
>  include/block/block.h | 1 +
>  3 files changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/block.c b/block.c
> index 0fe97de..af284e3 100644
> --- a/block.c
> +++ b/block.c
> @@ -3920,6 +3920,11 @@ const char *bdrv_get_device_name(const BlockDriverState *bs)
>      return bs->blk ? blk_name(bs->blk) : "";
>  }
>  
> +const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
> +{
> +    return bs->blk ? blk_name(bs->blk) : bs->node_name;
> +}
> +

Does this have uses beyond identifying @bs to the user?

>  int bdrv_get_flags(BlockDriverState *bs)
>  {
>      return bs->open_flags;
> diff --git a/block/quorum.c b/block/quorum.c
> index 437b122..f91ef75 100644
> --- a/block/quorum.c
> +++ b/block/quorum.c
> @@ -226,10 +226,7 @@ static void quorum_report_bad(QuorumAIOCB *acb, char *node_name, int ret)
>  
>  static void quorum_report_failure(QuorumAIOCB *acb)
>  {
> -    const char *reference = bdrv_get_device_name(acb->common.bs)[0] ?
> -                            bdrv_get_device_name(acb->common.bs) :
> -                            acb->common.bs->node_name;
> -
> +    const char *reference = bdrv_get_device_or_node_name(acb->common.bs);
>      qapi_event_send_quorum_failure(reference, acb->sector_num,
>                                     acb->nb_sectors, &error_abort);
>  }

Preexisting: what if reference is null?

event.json suggests it can't be null:

    ##
    # @QUORUM_FAILURE
    #
    # Emitted by the Quorum block driver if it fails to establish a quorum
    #
    # @reference: device name if defined else node name
    #
    # @sector-num: number of the first sector of the failed read operation
    #
    # @sectors-count: failed read operation sector count
    #
    # Since: 2.0
    ##
    { 'event': 'QUORUM_FAILURE',
      'data': { 'reference': 'str', 'sector-num': 'int', 'sectors-count': 'int' } }

> diff --git a/include/block/block.h b/include/block/block.h
> index 4c57d63..b285e0d 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -398,6 +398,7 @@ void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
>                           void *opaque);
>  const char *bdrv_get_node_name(const BlockDriverState *bs);
>  const char *bdrv_get_device_name(const BlockDriverState *bs);
> +const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
>  int bdrv_get_flags(BlockDriverState *bs);
>  int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
>                            const uint8_t *buf, int nb_sectors);

Re: [Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Max Reitz]

On 2015-03-19 at 11:43, Alberto Garcia wrote:
> This function gets the device name associated with a BlockDriverState,
> or its node name if the device name is empty.
>
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> ---
>   block.c               | 5 +++++
>   block/quorum.c        | 5 +----
>   include/block/block.h | 1 +
>   3 files changed, 7 insertions(+), 4 deletions(-)

Reviewed-by: Max Reitz <mreitz@redhat.com>

[Qemu-devel] [PATCH 1/3] block: add bdrv_get_device_or_node_name()

[Alberto Garcia]

This function gets the device name associated with a BlockDriverState,
or its node name if the device name is empty.

Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 block.c               | 5 +++++
 block/quorum.c        | 5 +----
 include/block/block.h | 1 +
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/block.c b/block.c
index 0fe97de..af284e3 100644
--- a/block.c
+++ b/block.c
@@ -3920,6 +3920,11 @@ const char *bdrv_get_device_name(const BlockDriverState *bs)
     return bs->blk ? blk_name(bs->blk) : "";
 }
 
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
+{
+    return bs->blk ? blk_name(bs->blk) : bs->node_name;
+}
+
 int bdrv_get_flags(BlockDriverState *bs)
 {
     return bs->open_flags;
diff --git a/block/quorum.c b/block/quorum.c
index 437b122..f91ef75 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -226,10 +226,7 @@ static void quorum_report_bad(QuorumAIOCB *acb, char *node_name, int ret)
 
 static void quorum_report_failure(QuorumAIOCB *acb)
 {
-    const char *reference = bdrv_get_device_name(acb->common.bs)[0] ?
-                            bdrv_get_device_name(acb->common.bs) :
-                            acb->common.bs->node_name;
-
+    const char *reference = bdrv_get_device_or_node_name(acb->common.bs);
     qapi_event_send_quorum_failure(reference, acb->sector_num,
                                    acb->nb_sectors, &error_abort);
 }
diff --git a/include/block/block.h b/include/block/block.h
index 4c57d63..b285e0d 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -398,6 +398,7 @@ void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
                          void *opaque);
 const char *bdrv_get_node_name(const BlockDriverState *bs);
 const char *bdrv_get_device_name(const BlockDriverState *bs);
+const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
 int bdrv_get_flags(BlockDriverState *bs);
 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
                           const uint8_t *buf, int nb_sectors);
-- 
2.1.4