Re: [PATCH V2 1/2] vdpa: Support config interrupt in vhost_vdpa

[Zhu Lingshan <lingshan.zhu@linux.intel.com>]

[-- Attachment #1.1: Type: text/plain, Size: 5338 bytes --]


On 4/26/2020 2:58 PM, Jason Wang wrote:
>
> On 2020/4/26 下午2:09, Zhu Lingshan wrote:
>> This commit implements config interrupt support in
>> vhost_vdpa layer.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/vdpa.c       | 47 
>> ++++++++++++++++++++++++++++++++++++++++++++++
>>   drivers/vhost/vhost.c      |  2 +-
>>   drivers/vhost/vhost.h      |  2 ++
>>   include/uapi/linux/vhost.h |  2 ++
>>   4 files changed, 52 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
>> index 421f02a..b94e349 100644
>> --- a/drivers/vhost/vdpa.c
>> +++ b/drivers/vhost/vdpa.c
>> @@ -21,6 +21,7 @@
>>   #include <linux/nospec.h>
>>   #include <linux/vhost.h>
>>   #include <linux/virtio_net.h>
>> +#include <linux/kernel.h>
>>     #include "vhost.h"
>>   @@ -70,6 +71,7 @@ struct vhost_vdpa {
>>       int nvqs;
>>       int virtio_id;
>>       int minor;
>> +    struct eventfd_ctx *config_ctx;
>>   };
>>     static DEFINE_IDA(vhost_vdpa_ida);
>> @@ -101,6 +103,17 @@ static irqreturn_t vhost_vdpa_virtqueue_cb(void 
>> *private)
>>       return IRQ_HANDLED;
>>   }
>>   +static irqreturn_t vhost_vdpa_config_cb(void *private)
>> +{
>> +    struct vhost_vdpa *v = private;
>> +    struct eventfd_ctx *config_ctx = v->config_ctx;
>> +
>> +    if (config_ctx)
>> +        eventfd_signal(config_ctx, 1);
>> +
>> +    return IRQ_HANDLED;
>> +}
>> +
>>   static void vhost_vdpa_reset(struct vhost_vdpa *v)
>>   {
>>       struct vdpa_device *vdpa = v->vdpa;
>> @@ -288,6 +301,36 @@ static long vhost_vdpa_get_vring_num(struct 
>> vhost_vdpa *v, u16 __user *argp)
>>       return 0;
>>   }
>>   +static void vhost_vdpa_config_put(struct vhost_vdpa *v)
>> +{
>> +    if (v->config_ctx)
>> +        eventfd_ctx_put(v->config_ctx);
>> +}
>> +
>> +static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 
>> __user *argp)
>> +{
>> +    struct vdpa_callback cb;
>> +    u32 fd;
>> +    struct eventfd_ctx *ctx;
>> +
>> +    cb.callback = vhost_vdpa_config_cb;
>> +    cb.private = v->vdpa;
>> +    if (copy_from_user(&fd, argp, sizeof(fd)))
>> +        return  -EFAULT;
>> +
>> +    ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd);
>> +    swap(ctx, v->config_ctx);
>> +
>> +    if (!IS_ERR_OR_NULL(ctx))
>> +        eventfd_ctx_put(ctx);
>> +
>> +    if (IS_ERR(v->config_ctx))
>> +        return PTR_ERR(v->config_ctx);
>> +
>> + v->vdpa->config->set_config_cb(v->vdpa, &cb);
>> +
>> +    return 0;
>> +}
>>   static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned 
>> int cmd,
>>                      void __user *argp)
>>   {
>> @@ -398,6 +441,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file 
>> *filep,
>>       case VHOST_SET_LOG_FD:
>>           r = -ENOIOCTLCMD;
>>           break;
>> +    case VHOST_VDPA_SET_CONFIG_CALL:
>> +        r = vhost_vdpa_set_config_call(v, argp);
>> +        break;
>>       default:
>>           r = vhost_dev_ioctl(&v->vdev, cmd, argp);
>>           if (r == -ENOIOCTLCMD)
>> @@ -734,6 +780,7 @@ static int vhost_vdpa_release(struct inode 
>> *inode, struct file *filep)
>>       vhost_dev_stop(&v->vdev);
>>       vhost_vdpa_iotlb_free(v);
>>       vhost_vdpa_free_domain(v);
>> +    vhost_vdpa_config_put(v);
>>       vhost_dev_cleanup(&v->vdev);
>>       kfree(v->vdev.vqs);
>>       mutex_unlock(&d->mutex);
>> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
>> index d450e16..e8f5b20 100644
>> --- a/drivers/vhost/vhost.c
>> +++ b/drivers/vhost/vhost.c
>> @@ -1590,7 +1590,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, 
>> unsigned int ioctl, void __user *arg
>>               r = -EFAULT;
>>               break;
>>           }
>> -        ctx = f.fd == -1 ? NULL : eventfd_ctx_fdget(f.fd);
>> +        ctx = f.fd == VHOST_FILE_UNBIND ? NULL : 
>> eventfd_ctx_fdget(f.fd);
>>           if (IS_ERR(ctx)) {
>>               r = PTR_ERR(ctx);
>>               break;
>> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
>> index 1813821..8663139 100644
>> --- a/drivers/vhost/vhost.h
>> +++ b/drivers/vhost/vhost.h
>> @@ -18,6 +18,8 @@
>>   typedef void (*vhost_work_fn_t)(struct vhost_work *work);
>>     #define VHOST_WORK_QUEUED 1
>> +#define VHOST_FILE_UNBIND -1
>
>
> I think it's better to document this in uapi.

OK, will define this in uapi header.

>
>
>> +
>>   struct vhost_work {
>>       struct llist_node      node;
>>       vhost_work_fn_t          fn;
>> diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
>> index 9fe72e4..345acb3 100644
>> --- a/include/uapi/linux/vhost.h
>> +++ b/include/uapi/linux/vhost.h
>> @@ -140,4 +140,6 @@
>>   /* Get the max ring size. */
>>   #define VHOST_VDPA_GET_VRING_NUM _IOR(VHOST_VIRTIO, 0x76, __u16)
>>   +/* Set event fd for config interrupt*/
>> +#define VHOST_VDPA_SET_CONFIG_CALL _IOW(VHOST_VIRTIO, 0x77, u32)
>>   #endif
>
>
> Should be "int" instead of "u32".

Oh, right, it could be -1

>
> Thanks
>

[-- Attachment #1.2: Type: text/html, Size: 11588 bytes --]

[-- Attachment #2: Type: text/plain, Size: 183 bytes --]

_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization