From 4b6ec919b84830949313c805c586fb34f141ce0c Mon Sep 17 00:00:00 2001 From: Feng Liu Date: Fri, 10 Mar 2023 07:34:28 +0200 Subject: [PATCH] virtio_ring: Use const to annotate read-only pointer params Add const to make the read-only pointer parameters clear, similar to many existing functions. To implement this change, the commit also introduces the use of `container_of_const` to implement `to_vvq`, which ensures the const-ness of read-only parameters and avoids accidental modification of their members. Signed-off-by: Feng Liu Reviewed-by: Jiri Pirko Reviewed-by: Parav Pandit Reviewed-by: Gavin Li Reviewed-by: Bodong Wang Message-Id: <20230310053428.3376-4-feliu@nvidia.com> Signed-off-by: Michael S. Tsirkin --- drivers/virtio/virtio_ring.c | 36 ++++++++++++++++++------------------ include/linux/virtio.h | 14 +++++++------- 2 files changed, 25 insertions(+), 25 deletions(-) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index a26fab9..4c3bb0d 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -231,9 +231,9 @@ static void vring_free(struct virtqueue *_vq); * Helpers. */ -#define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq) +#define to_vvq(_vq) container_of_const(_vq, struct vring_virtqueue, vq) -static bool virtqueue_use_indirect(struct vring_virtqueue *vq, +static bool virtqueue_use_indirect(const struct vring_virtqueue *vq, unsigned int total_sg) { /* @@ -269,7 +269,7 @@ static bool virtqueue_use_indirect(struct vring_virtqueue *vq, * unconditionally on data path. */ -static bool vring_use_dma_api(struct virtio_device *vdev) +static bool vring_use_dma_api(const struct virtio_device *vdev) { if (!virtio_has_dma_quirk(vdev)) return true; @@ -289,7 +289,7 @@ static bool vring_use_dma_api(struct virtio_device *vdev) return false; } -size_t virtio_max_dma_size(struct virtio_device *vdev) +size_t virtio_max_dma_size(const struct virtio_device *vdev) { size_t max_segment_size = SIZE_MAX; @@ -423,7 +423,7 @@ static void virtqueue_init(struct vring_virtqueue *vq, u32 num) */ static void vring_unmap_one_split_indirect(const struct vring_virtqueue *vq, - struct vring_desc *desc) + const struct vring_desc *desc) { u16 flags; @@ -1183,7 +1183,7 @@ static u16 packed_last_used(u16 last_used_idx) } static void vring_unmap_extra_packed(const struct vring_virtqueue *vq, - struct vring_desc_extra *extra) + const struct vring_desc_extra *extra) { u16 flags; @@ -1206,7 +1206,7 @@ static void vring_unmap_extra_packed(const struct vring_virtqueue *vq, } static void vring_unmap_desc_packed(const struct vring_virtqueue *vq, - struct vring_packed_desc *desc) + const struct vring_packed_desc *desc) { u16 flags; @@ -2786,10 +2786,10 @@ EXPORT_SYMBOL_GPL(vring_transport_features); * Returns the size of the vring. This is mainly used for boasting to * userspace. Unlike other operations, this need not be serialized. */ -unsigned int virtqueue_get_vring_size(struct virtqueue *_vq) +unsigned int virtqueue_get_vring_size(const struct virtqueue *_vq) { - struct vring_virtqueue *vq = to_vvq(_vq); + const struct vring_virtqueue *vq = to_vvq(_vq); return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num; } @@ -2819,9 +2819,9 @@ void __virtqueue_unbreak(struct virtqueue *_vq) } EXPORT_SYMBOL_GPL(__virtqueue_unbreak); -bool virtqueue_is_broken(struct virtqueue *_vq) +bool virtqueue_is_broken(const struct virtqueue *_vq) { - struct vring_virtqueue *vq = to_vvq(_vq); + const struct vring_virtqueue *vq = to_vvq(_vq); return READ_ONCE(vq->broken); } @@ -2868,9 +2868,9 @@ void __virtio_unbreak_device(struct virtio_device *dev) } EXPORT_SYMBOL_GPL(__virtio_unbreak_device); -dma_addr_t virtqueue_get_desc_addr(struct virtqueue *_vq) +dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *_vq) { - struct vring_virtqueue *vq = to_vvq(_vq); + const struct vring_virtqueue *vq = to_vvq(_vq); BUG_ON(!vq->we_own_ring); @@ -2881,9 +2881,9 @@ dma_addr_t virtqueue_get_desc_addr(struct virtqueue *_vq) } EXPORT_SYMBOL_GPL(virtqueue_get_desc_addr); -dma_addr_t virtqueue_get_avail_addr(struct virtqueue *_vq) +dma_addr_t virtqueue_get_avail_addr(const struct virtqueue *_vq) { - struct vring_virtqueue *vq = to_vvq(_vq); + const struct vring_virtqueue *vq = to_vvq(_vq); BUG_ON(!vq->we_own_ring); @@ -2895,9 +2895,9 @@ dma_addr_t virtqueue_get_avail_addr(struct virtqueue *_vq) } EXPORT_SYMBOL_GPL(virtqueue_get_avail_addr); -dma_addr_t virtqueue_get_used_addr(struct virtqueue *_vq) +dma_addr_t virtqueue_get_used_addr(const struct virtqueue *_vq) { - struct vring_virtqueue *vq = to_vvq(_vq); + const struct vring_virtqueue *vq = to_vvq(_vq); BUG_ON(!vq->we_own_ring); @@ -2910,7 +2910,7 @@ dma_addr_t virtqueue_get_used_addr(struct virtqueue *_vq) EXPORT_SYMBOL_GPL(virtqueue_get_used_addr); /* Only available for split ring */ -const struct vring *virtqueue_get_vring(struct virtqueue *vq) +const struct vring *virtqueue_get_vring(const struct virtqueue *vq) { return &to_vvq(vq)->split.vring; } diff --git a/include/linux/virtio.h b/include/linux/virtio.h index d6e161a..b93238d 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -84,14 +84,14 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *vq); void *virtqueue_detach_unused_buf(struct virtqueue *vq); -unsigned int virtqueue_get_vring_size(struct virtqueue *vq); +unsigned int virtqueue_get_vring_size(const struct virtqueue *vq); -bool virtqueue_is_broken(struct virtqueue *vq); +bool virtqueue_is_broken(const struct virtqueue *vq); -const struct vring *virtqueue_get_vring(struct virtqueue *vq); -dma_addr_t virtqueue_get_desc_addr(struct virtqueue *vq); -dma_addr_t virtqueue_get_avail_addr(struct virtqueue *vq); -dma_addr_t virtqueue_get_used_addr(struct virtqueue *vq); +const struct vring *virtqueue_get_vring(const struct virtqueue *vq); +dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *vq); +dma_addr_t virtqueue_get_avail_addr(const struct virtqueue *vq); +dma_addr_t virtqueue_get_used_addr(const struct virtqueue *vq); int virtqueue_resize(struct virtqueue *vq, u32 num, void (*recycle)(struct virtqueue *vq, void *buf)); @@ -147,7 +147,7 @@ int virtio_device_restore(struct virtio_device *dev); #endif void virtio_reset_device(struct virtio_device *dev); -size_t virtio_max_dma_size(struct virtio_device *vdev); +size_t virtio_max_dma_size(const struct virtio_device *vdev); #define virtio_device_for_each_vq(vdev, vq) \ list_for_each_entry(vq, &vdev->vqs, list) -- 2.7.4