qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Stefano Garzarella <sgarzare@redhat.com>
To: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, mst@redhat.com
Subject: Re: [PATCH 5/7] vhost: Distinguish errors in vhost_dev_get_config()
Date: Thu, 10 Jun 2021 11:16:20 +0200	[thread overview]
Message-ID: <20210610091620.t5z44zo6nu547grq@steredhat> (raw)
In-Reply-To: <20210609154658.350308-6-kwolf@redhat.com>

On Wed, Jun 09, 2021 at 05:46:56PM +0200, Kevin Wolf wrote:
>Instead of just returning 0/-1 and letting the caller make up a
>meaningless error message, add an Error parameter to allow reporting the
>real error and switch to 0/-errno so that different kind of errors can
>be distinguished in the caller.
>
>Signed-off-by: Kevin Wolf <kwolf@redhat.com>
>---
> include/hw/virtio/vhost-backend.h |  2 +-
> include/hw/virtio/vhost.h         |  4 ++--
> hw/block/vhost-user-blk.c         |  9 +++++----
> hw/display/vhost-user-gpu.c       |  6 ++++--
> hw/input/vhost-user-input.c       |  6 ++++--
> hw/net/vhost_net.c                |  2 +-
> hw/virtio/vhost-user-vsock.c      |  9 +++++----
> hw/virtio/vhost-user.c            | 24 ++++++++++++------------
> hw/virtio/vhost-vdpa.c            |  2 +-
> hw/virtio/vhost.c                 | 14 +++++++++++---
> 10 files changed, 46 insertions(+), 32 deletions(-)
>
>diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h
>index 728ebb0ed9..8475c5a29d 100644
>--- a/include/hw/virtio/vhost-backend.h
>+++ b/include/hw/virtio/vhost-backend.h
>@@ -98,7 +98,7 @@ typedef int (*vhost_set_config_op)(struct vhost_dev *dev, const uint8_t *data,
>                                    uint32_t offset, uint32_t size,
>                                    uint32_t flags);
> typedef int (*vhost_get_config_op)(struct vhost_dev *dev, uint8_t *config,
>-                                   uint32_t config_len);
>+                                   uint32_t config_len, Error **errp);
>
> typedef int (*vhost_crypto_create_session_op)(struct vhost_dev *dev,
>                                               void *session_info,
>diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
>index 2d7aaad67b..045d0fd9f2 100644
>--- a/include/hw/virtio/vhost.h
>+++ b/include/hw/virtio/vhost.h
>@@ -130,8 +130,8 @@ int vhost_net_set_backend(struct vhost_dev *hdev,
>                           struct vhost_vring_file *file);
>
> int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write);
>-int vhost_dev_get_config(struct vhost_dev *dev, uint8_t *config,
>-                         uint32_t config_len);
>+int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config,
>+                         uint32_t config_len, Error **errp);
> int vhost_dev_set_config(struct vhost_dev *dev, const uint8_t *data,
>                          uint32_t offset, uint32_t size, uint32_t flags);
> /* notifier callback in case vhost device config space changed
>diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
>index e9382e152a..3770f715da 100644
>--- a/hw/block/vhost-user-blk.c
>+++ b/hw/block/vhost-user-blk.c
>@@ -91,11 +91,13 @@ static int vhost_user_blk_handle_config_change(struct vhost_dev *dev)
>     int ret;
>     struct virtio_blk_config blkcfg;
>     VHostUserBlk *s = VHOST_USER_BLK(dev->vdev);
>+    Error *local_err = NULL;
>
>     ret = vhost_dev_get_config(dev, (uint8_t *)&blkcfg,
>-                               sizeof(struct virtio_blk_config));
>+                               sizeof(struct virtio_blk_config),
>+                               &local_err);
>     if (ret < 0) {
>-        error_report("get config space failed");
>+        error_report_err(local_err);
>         return -1;
>     }
>
>@@ -478,9 +480,8 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
>     assert(s->connected);
>
>     ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg,
>-                               sizeof(struct virtio_blk_config));
>+                               sizeof(struct virtio_blk_config), errp);
>     if (ret < 0) {
>-        error_setg(errp, "vhost-user-blk: get block config failed");
>         goto vhost_err;
>     }
>
>diff --git a/hw/display/vhost-user-gpu.c b/hw/display/vhost-user-gpu.c
>index 6cdaa1c73b..389199e6ca 100644
>--- a/hw/display/vhost-user-gpu.c
>+++ b/hw/display/vhost-user-gpu.c
>@@ -415,14 +415,16 @@ vhost_user_gpu_get_config(VirtIODevice *vdev, uint8_t *config_data)
>     VirtIOGPUBase *b = VIRTIO_GPU_BASE(vdev);
>     struct virtio_gpu_config *vgconfig =
>         (struct virtio_gpu_config *)config_data;
>+    Error *local_err = NULL;
>     int ret;
>
>     memset(config_data, 0, sizeof(struct virtio_gpu_config));
>
>     ret = vhost_dev_get_config(&g->vhost->dev,
>-                               config_data, sizeof(struct virtio_gpu_config));
>+                               config_data, sizeof(struct virtio_gpu_config),
>+                               &local_err);
>     if (ret) {
>-        error_report("vhost-user-gpu: get device config space failed");
>+        error_report_err(local_err);
>         return;
>     }
>
>diff --git a/hw/input/vhost-user-input.c b/hw/input/vhost-user-input.c
>index 63984a8ba7..273e96a7b1 100644
>--- a/hw/input/vhost-user-input.c
>+++ b/hw/input/vhost-user-input.c
>@@ -49,13 +49,15 @@ static void vhost_input_get_config(VirtIODevice *vdev, uint8_t *config_data)
> {
>     VirtIOInput *vinput = VIRTIO_INPUT(vdev);
>     VHostUserInput *vhi = VHOST_USER_INPUT(vdev);
>+    Error *local_err = NULL;
>     int ret;
>
>     memset(config_data, 0, vinput->cfg_size);
>
>-    ret = vhost_dev_get_config(&vhi->vhost->dev, config_data, vinput->cfg_size);
>+    ret = vhost_dev_get_config(&vhi->vhost->dev, config_data, vinput->cfg_size,
>+                               &local_err);
>     if (ret) {
>-        error_report("vhost-user-input: get device config space failed");
>+        error_report_err(local_err);
>         return;
>     }
> }
>diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
>index 447b119f85..10a7780a13 100644
>--- a/hw/net/vhost_net.c
>+++ b/hw/net/vhost_net.c
>@@ -117,7 +117,7 @@ uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
> int vhost_net_get_config(struct vhost_net *net,  uint8_t *config,
>                          uint32_t config_len)
> {
>-    return vhost_dev_get_config(&net->dev, config, config_len);
>+    return vhost_dev_get_config(&net->dev, config, config_len, NULL);
> }
> int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
>                          uint32_t offset, uint32_t size, uint32_t flags)
>diff --git a/hw/virtio/vhost-user-vsock.c b/hw/virtio/vhost-user-vsock.c
>index b6a4a25ea1..6095ed7349 100644
>--- a/hw/virtio/vhost-user-vsock.c
>+++ b/hw/virtio/vhost-user-vsock.c
>@@ -34,10 +34,12 @@ static void vuv_get_config(VirtIODevice *vdev, uint8_t *config)
> static int vuv_handle_config_change(struct vhost_dev *dev)
> {
>     VHostUserVSock *vsock = VHOST_USER_VSOCK(dev->vdev);
>+    Error *local_err = NULL;
>     int ret = vhost_dev_get_config(dev, (uint8_t *)&vsock->vsockcfg,
>-                                   sizeof(struct virtio_vsock_config));
>+                                   sizeof(struct virtio_vsock_config),
>+                                   &local_err);
>     if (ret < 0) {
>-        error_report("get config space failed");
>+        error_report_err(local_err);
>         return -1;
>     }
>
>@@ -114,9 +116,8 @@ static void vuv_device_realize(DeviceState *dev, Error **errp)
>     }
>
>     ret = vhost_dev_get_config(&vvc->vhost_dev, (uint8_t *)&vsock->vsockcfg,
>-                               sizeof(struct virtio_vsock_config));
>+                               sizeof(struct virtio_vsock_config), errp);
>     if (ret < 0) {
>-        error_setg_errno(errp, -ret, "get config space failed");
>         goto err_vhost_dev;
>     }
>
>diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
>index 889559d86a..1ac4a2ebec 100644
>--- a/hw/virtio/vhost-user.c
>+++ b/hw/virtio/vhost-user.c
>@@ -2117,7 +2117,7 @@ static void vhost_user_set_iotlb_callback(struct vhost_dev *dev, int enabled)
> }
>
> static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config,
>-                                 uint32_t config_len)
>+                                 uint32_t config_len, Error **errp)
> {
>     VhostUserMsg msg = {
>         .hdr.request = VHOST_USER_GET_CONFIG,
>@@ -2127,32 +2127,32 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config,
>
>     if (!virtio_has_feature(dev->protocol_features,
>                 VHOST_USER_PROTOCOL_F_CONFIG)) {
>-        return -1;
>+        error_setg(errp, "VHOST_USER_PROTOCOL_F_CONFIG not supported");
>+        return -EINVAL;
>     }
>
>-    if (config_len > VHOST_USER_MAX_CONFIG_SIZE) {
>-        return -1;
>-    }
>+    assert(config_len <= VHOST_USER_MAX_CONFIG_SIZE);
>
>     msg.payload.config.offset = 0;
>     msg.payload.config.size = config_len;
>     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
>-        return -1;
>+        return -EPROTO;
>     }
>
>     if (vhost_user_read(dev, &msg) < 0) {
>-        return -1;
>+        return -EPROTO;
>     }
>
>     if (msg.hdr.request != VHOST_USER_GET_CONFIG) {
>-        error_report("Received unexpected msg type. Expected %d received %d",
>-                     VHOST_USER_GET_CONFIG, msg.hdr.request);
>-        return -1;
>+        error_setg(errp,
>+                   "Received unexpected msg type. Expected %d received %d",
>+                   VHOST_USER_GET_CONFIG, msg.hdr.request);
>+        return -EINVAL;
>     }
>
>     if (msg.hdr.size != VHOST_USER_CONFIG_HDR_SIZE + config_len) {
>-        error_report("Received bad msg size.");
>-        return -1;
>+        error_setg(errp, "Received bad msg size.");
>+        return -EINVAL;
>     }
>
>     memcpy(config, msg.payload.config.region, config_len);
>diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
>index 71897c1a01..6b6f974a83 100644
>--- a/hw/virtio/vhost-vdpa.c
>+++ b/hw/virtio/vhost-vdpa.c
>@@ -451,7 +451,7 @@ static int vhost_vdpa_set_config(struct vhost_dev *dev, const uint8_t *data,
> }
>
> static int vhost_vdpa_get_config(struct vhost_dev *dev, uint8_t *config,
>-                                   uint32_t config_len)
>+                                   uint32_t config_len, Error **errp)
> {
>     struct vhost_vdpa_config *v_config;
>     unsigned long config_size = offsetof(struct vhost_vdpa_config, buf);
>diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
>index c7f9d8bb06..1b66f1de70 100644
>--- a/hw/virtio/vhost.c
>+++ b/hw/virtio/vhost.c
>@@ -1562,15 +1562,23 @@ void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits,
> }
>
> int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config,
>-                         uint32_t config_len)
>+                         uint32_t config_len, Error **errp)
> {
>+    ERRP_GUARD();
>+    int ret;
>+
>     assert(hdev->vhost_ops);
>
>     if (hdev->vhost_ops->vhost_get_config) {
>-        return hdev->vhost_ops->vhost_get_config(hdev, config, config_len);
>+        ret = hdev->vhost_ops->vhost_get_config(hdev, config, config_len, errp);
>+        if (ret < 0 && !*errp) {
>+            error_setg_errno(errp, -ret, "vhost_get_config failed");
>+        }
>+        return ret;
>     }
>
>-    return -1;
>+    error_setg(errp, "vhost_dev_get_config not implemented");
                         ^
Maybe I'd replace s/vhost_dev_get_config/vhost_get_config

But it's not that important:

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>



  reply	other threads:[~2021-06-10  9:17 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-09 15:46 [PATCH 0/7] vhost-user-blk: Implement reconnection during realize Kevin Wolf
2021-06-09 15:46 ` [PATCH 1/7] vhost: Add Error parameter to vhost_dev_init() Kevin Wolf
2021-06-10  9:05   ` Stefano Garzarella
2021-06-11 19:14   ` Raphael Norwitz
2021-06-09 15:46 ` [PATCH 2/7] vhost: Distinguish errors in vhost_backend_init() Kevin Wolf
2021-06-10  9:07   ` Stefano Garzarella
2021-06-11 19:43   ` Raphael Norwitz
2021-06-09 15:46 ` [PATCH 3/7] vhost: Return 0/-errno in vhost_dev_init() Kevin Wolf
2021-06-10  9:09   ` Stefano Garzarella
2021-06-11 19:49   ` Raphael Norwitz
2021-06-09 15:46 ` [PATCH 4/7] vhost-user-blk: Add Error parameter to vhost_user_blk_start() Kevin Wolf
2021-06-10  9:11   ` Stefano Garzarella
2021-06-11 19:55   ` Raphael Norwitz
2021-06-09 15:46 ` [PATCH 5/7] vhost: Distinguish errors in vhost_dev_get_config() Kevin Wolf
2021-06-10  9:16   ` Stefano Garzarella [this message]
2021-06-11 20:08   ` Raphael Norwitz
2021-06-09 15:46 ` [PATCH 6/7] vhost-user-blk: Factor out vhost_user_blk_realize_connect() Kevin Wolf
2021-06-10  9:18   ` Stefano Garzarella
2021-06-11 20:11   ` Raphael Norwitz
2021-06-09 15:46 ` [PATCH 7/7] vhost-user-blk: Implement reconnection during realize Kevin Wolf
2021-06-10  9:23   ` Stefano Garzarella
2021-06-11 20:15   ` Raphael Norwitz
2021-06-30 12:39 ` [PATCH 0/7] " Kevin Wolf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210610091620.t5z44zo6nu547grq@steredhat \
    --to=sgarzare@redhat.com \
    --cc=kwolf@redhat.com \
    --cc=mst@redhat.com \
    --cc=qemu-block@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).