[PATCH] mshv_eventfd: convert to CLASS(fd)

[PATCH] mshv_eventfd: convert to CLASS(fd)

[Al Viro]

[in viro/vfs.git #work.fd; if nobody objects, into #for-next it goes...]

similar to 66635b077624 ("assorted variants of irqfd setup: convert
to CLASS(fd)") a year ago...
    
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
diff --git a/drivers/hv/mshv_eventfd.c b/drivers/hv/mshv_eventfd.c
index 8dd22be2ca0b..48c514da34eb 100644
--- a/drivers/hv/mshv_eventfd.c
+++ b/drivers/hv/mshv_eventfd.c
@@ -377,10 +377,11 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
 	struct eventfd_ctx *eventfd = NULL, *resamplefd = NULL;
 	struct mshv_irqfd *irqfd, *tmp;
 	unsigned int events;
-	struct fd f;
 	int ret;
 	int idx;
 
+	CLASS(fd, f)(args->fd);
+
 	irqfd = kzalloc(sizeof(*irqfd), GFP_KERNEL);
 	if (!irqfd)
 		return -ENOMEM;
@@ -390,8 +391,7 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
 	INIT_WORK(&irqfd->irqfd_shutdown, mshv_irqfd_shutdown);
 	seqcount_spinlock_init(&irqfd->irqfd_irqe_sc, &pt->pt_irqfds_lock);
 
-	f = fdget(args->fd);
-	if (!fd_file(f)) {
+	if (fd_empty(f)) {
 		ret = -EBADF;
 		goto out;
 	}
@@ -496,12 +496,6 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
 		mshv_assert_irq_slow(irqfd);
 
 	srcu_read_unlock(&pt->pt_irq_srcu, idx);
-	/*
-	 * do not drop the file until the irqfd is fully initialized, otherwise
-	 * we might race against the POLLHUP
-	 */
-	fdput(f);
-
 	return 0;
 
 fail:
@@ -514,8 +508,6 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
 	if (eventfd && !IS_ERR(eventfd))
 		eventfd_ctx_put(eventfd);
 
-	fdput(f);
-
 out:
 	kfree(irqfd);
 	return ret;

Re: [PATCH] mshv_eventfd: convert to CLASS(fd)

[Wei Liu]

On Sat, Jul 12, 2025 at 05:52:44PM +0100, Al Viro wrote:
> [in viro/vfs.git #work.fd; if nobody objects, into #for-next it goes...]
> 
> similar to 66635b077624 ("assorted variants of irqfd setup: convert
> to CLASS(fd)") a year ago...
>     
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Thanks for the patch, Al.

Acked-by: Wei Liu <wei.liu@kernel.org>

Re: [PATCH] mshv_eventfd: convert to CLASS(fd)

[Nuno Das Neves]

On 7/12/2025 9:52 AM, Al Viro wrote:
> [in viro/vfs.git #work.fd; if nobody objects, into #for-next it goes...]
> 
> similar to 66635b077624 ("assorted variants of irqfd setup: convert
> to CLASS(fd)") a year ago...
>     
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> ---
> diff --git a/drivers/hv/mshv_eventfd.c b/drivers/hv/mshv_eventfd.c
> index 8dd22be2ca0b..48c514da34eb 100644
> --- a/drivers/hv/mshv_eventfd.c
> +++ b/drivers/hv/mshv_eventfd.c
> @@ -377,10 +377,11 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
>  	struct eventfd_ctx *eventfd = NULL, *resamplefd = NULL;
>  	struct mshv_irqfd *irqfd, *tmp;
>  	unsigned int events;
> -	struct fd f;
>  	int ret;
>  	int idx;
>  
> +	CLASS(fd, f)(args->fd);
> +
>  	irqfd = kzalloc(sizeof(*irqfd), GFP_KERNEL);
>  	if (!irqfd)
>  		return -ENOMEM;
> @@ -390,8 +391,7 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
>  	INIT_WORK(&irqfd->irqfd_shutdown, mshv_irqfd_shutdown);
>  	seqcount_spinlock_init(&irqfd->irqfd_irqe_sc, &pt->pt_irqfds_lock);
>  
> -	f = fdget(args->fd);
> -	if (!fd_file(f)) {
> +	if (fd_empty(f)) {
>  		ret = -EBADF;
>  		goto out;
>  	}
> @@ -496,12 +496,6 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
>  		mshv_assert_irq_slow(irqfd);
>  
>  	srcu_read_unlock(&pt->pt_irq_srcu, idx);
> -	/*
> -	 * do not drop the file until the irqfd is fully initialized, otherwise
> -	 * we might race against the POLLHUP
> -	 */
> -	fdput(f);
> -
>  	return 0;
>  
>  fail:
> @@ -514,8 +508,6 @@ static int mshv_irqfd_assign(struct mshv_partition *pt,
>  	if (eventfd && !IS_ERR(eventfd))
>  		eventfd_ctx_put(eventfd);
>  
> -	fdput(f);
> -
>  out:
>  	kfree(irqfd);
>  	return ret;

Looks fine to me, thanks.

Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>