From 70f88436aa5a8aeddd33e4d06270146af5d5bb52 Mon Sep 17 00:00:00 2001 From: Ilya Maximets Date: Wed, 27 Sep 2023 15:59:42 +0200 Subject: [PATCH] virtio: remove unused next argument from virtqueue_split_read_next_desc() The 'next' was converted from a local variable to an output parameter in commit: 412e0e81b174 ("virtio: handle virtqueue_read_next_desc() errors") But all the actual uses of the 'i/next' as an output were removed a few months prior in commit: aa570d6fb6bd ("virtio: combine the read of a descriptor") Remove the unused argument to simplify the code. Also, adding a comment to the function to describe what it is actually doing, as it is not obvious that the 'desc' is both an input and an output argument. Signed-off-by: Ilya Maximets Message-Id: <20230927140016.2317404-3-i.maximets@ovn.org> Reviewed-by: Stefan Hajnoczi Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 87e8f990c5..6facd64fbc 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -1049,9 +1049,10 @@ enum { VIRTQUEUE_READ_DESC_MORE = 1, /* more buffers in chain */ }; +/* Reads the 'desc->next' descriptor into '*desc'. */ static int virtqueue_split_read_next_desc(VirtIODevice *vdev, VRingDesc *desc, MemoryRegionCache *desc_cache, - unsigned int max, unsigned int *next) + unsigned int max) { /* If this descriptor says it doesn't chain, we're done. */ if (!(desc->flags & VRING_DESC_F_NEXT)) { @@ -1059,14 +1060,12 @@ static int virtqueue_split_read_next_desc(VirtIODevice *vdev, VRingDesc *desc, } /* Check they're not leading us off end of descriptors. */ - *next = desc->next; - - if (*next >= max) { - virtio_error(vdev, "Desc next is %u", *next); + if (desc->next >= max) { + virtio_error(vdev, "Desc next is %u", desc->next); return VIRTQUEUE_READ_DESC_ERROR; } - vring_split_desc_read(vdev, desc, desc_cache, *next); + vring_split_desc_read(vdev, desc, desc_cache, desc->next); return VIRTQUEUE_READ_DESC_MORE; } @@ -1146,7 +1145,7 @@ static void virtqueue_split_get_avail_bytes(VirtQueue *vq, goto done; } - rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i); + rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max); } while (rc == VIRTQUEUE_READ_DESC_MORE); if (rc == VIRTQUEUE_READ_DESC_ERROR) { @@ -1601,7 +1600,7 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t sz) goto err_undo_map; } - rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i); + rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max); } while (rc == VIRTQUEUE_READ_DESC_MORE); if (rc == VIRTQUEUE_READ_DESC_ERROR) { @@ -4055,8 +4054,7 @@ VirtioQueueElement *qmp_x_query_virtio_queue_element(const char *path, list = node; ndescs++; - rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, - max, &i); + rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max); } while (rc == VIRTQUEUE_READ_DESC_MORE); element->descs = list; done: