[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [RFC PATCH 22/41] block: Add BdrvChildRole.get_link_name()
From: |
Kevin Wolf |
Subject: |
[Qemu-devel] [RFC PATCH 22/41] block: Add BdrvChildRole.get_link_name() |
Date: |
Mon, 13 Feb 2017 18:22:44 +0100 |
For meaningful error messages in the permission system, we want to allow
the parent of a BdrvChild to generate some kind of human-readable
identifier for the link represented by the BdrvChild.
Signed-off-by: Kevin Wolf <address@hidden>
---
block.c | 8 ++++++++
block/block-backend.c | 20 ++++++++++++++++++++
include/block/block_int.h | 4 ++++
3 files changed, 32 insertions(+)
diff --git a/block.c b/block.c
index fd06549..2116542 100644
--- a/block.c
+++ b/block.c
@@ -800,6 +800,13 @@ const BdrvChildRole child_format = {
.drained_end = bdrv_child_cb_drained_end,
};
+static char *bdrv_backing_link_name(BdrvChild *c)
+{
+ BlockDriverState *parent = c->opaque;
+ return g_strdup_printf("backing file link from %s",
+ bdrv_get_device_or_node_name(parent));
+}
+
/*
* Returns the options and flags that bs->backing should get, based on the
* given options and flags for the parent BDS
@@ -825,6 +832,7 @@ static void bdrv_backing_options(int *child_flags, QDict
*child_options,
}
static const BdrvChildRole child_backing = {
+ .get_link_name = bdrv_backing_link_name,
.inherit_options = bdrv_backing_options,
.drained_begin = bdrv_child_cb_drained_begin,
.drained_end = bdrv_child_cb_drained_end,
diff --git a/block/block-backend.c b/block/block-backend.c
index 0c23add..a314284 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -80,6 +80,7 @@ static const AIOCBInfo block_backend_aiocb_info = {
static void drive_info_del(DriveInfo *dinfo);
static BlockBackend *bdrv_first_blk(BlockDriverState *bs);
+static char *blk_get_attached_dev_id(BlockBackend *blk);
/* All BlockBackends */
static QTAILQ_HEAD(, BlockBackend) block_backends =
@@ -102,6 +103,24 @@ static void blk_root_drained_end(BdrvChild *child);
static void blk_root_change_media(BdrvChild *child, bool load);
static void blk_root_resize(BdrvChild *child);
+static char *blk_root_get_link_name(BdrvChild *child)
+{
+ BlockBackend *blk = child->opaque;
+ char *dev_id;
+
+ if (blk->name) {
+ return g_strdup(blk->name);
+ }
+
+ dev_id = blk_get_attached_dev_id(blk);
+ if (*dev_id) {
+ return dev_id;
+ } else {
+ g_free(dev_id);
+ return g_strdup("a block device");
+ }
+}
+
static const char *blk_root_get_name(BdrvChild *child)
{
return blk_name(child->opaque);
@@ -113,6 +132,7 @@ static const BdrvChildRole child_root = {
.change_media = blk_root_change_media,
.resize = blk_root_resize,
.get_name = blk_root_get_name,
+ .get_link_name = blk_root_get_link_name,
.drained_begin = blk_root_drained_begin,
.drained_end = blk_root_drained_end,
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 7558f99..a5557b1 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -438,6 +438,10 @@ struct BdrvChildRole {
* name), or NULL if the parent can't provide a better name. */
const char* (*get_name)(BdrvChild *child);
+ /* Returns a malloced name that describes the link from the parent to the
+ * child. The caller is responsible for freeing the memory. */
+ char* (*get_link_name)(BdrvChild *child);
+
/*
* If this pair of functions is implemented, the parent doesn't issue new
* requests after returning from .drained_begin() until .drained_end() is
--
1.8.3.1
- Re: [Qemu-devel] [RFC PATCH 16/41] block: Add error parameter to blk_insert_bs(), (continued)
[Qemu-devel] [RFC PATCH 18/41] block: Allow error return in BlockDevOps.change_media_cb(), Kevin Wolf, 2017/02/13
[Qemu-devel] [RFC PATCH 19/41] hw/block: Request permissions, Kevin Wolf, 2017/02/13
[Qemu-devel] [RFC PATCH 21/41] blockjob: Add permissions to block_job_create(), Kevin Wolf, 2017/02/13
[Qemu-devel] [RFC PATCH 22/41] block: Add BdrvChildRole.get_link_name(),
Kevin Wolf <=
[Qemu-devel] [RFC PATCH 20/41] hw/block: Introduce share-rw qdev property, Kevin Wolf, 2017/02/13
[Qemu-devel] [RFC PATCH 24/41] block: Add BdrvChildRole.stay_at_node, Kevin Wolf, 2017/02/13
[Qemu-devel] [RFC PATCH 25/41] blockjob: Add permissions to block_job_add_bdrv(), Kevin Wolf, 2017/02/13
[Qemu-devel] [RFC PATCH 23/41] block: Include details on permission errors in message, Kevin Wolf, 2017/02/13