On Thu, Mar 28, 2024 at 3:42 PM Xuan Zhuo [off-list ref] wrote:

On Thu, 28 Mar 2024 15:06:33 +0800, Jason Wang [off-list ref] wrote:

quoted

On Wed, Mar 27, 2024 at 7:14 PM Xuan Zhuo [off-list ref] wrote:

quoted

As discussed:
http://lore.kernel.org/all/CACGkMEug-=C+VQhkMYSgUKMC==04m7-uem_yC21bgGkKZh845w@mail.gmail.com (local)

When the vq is premapped mode, the driver manages the dma
info is a good way.

So this commit make the virtio core not to store the dma
info and release the memory which is used to store the dma
info.

If the use_dma_api is false, the memory is also not allocated.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
 drivers/virtio/virtio_ring.c | 120 ++++++++++++++++++++++++++++-------
 1 file changed, 97 insertions(+), 23 deletions(-)

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 1f7c96543d58..08e4f6e1d722 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c

@@ -69,23 +69,26 @@

 struct vring_desc_state_split {
        void *data;                     /* Data for callback. */
-       struct vring_desc_extra *indir_desc;    /* Indirect descriptor, if any. */
+       struct vring_desc_dma *indir_desc;      /* Indirect descriptor, if any. */
 };

 struct vring_desc_state_packed {
        void *data;                     /* Data for callback. */
-       struct vring_desc_extra *indir_desc; /* Indirect descriptor, if any. */
+       struct vring_desc_dma *indir_desc; /* Indirect descriptor, if any. */
        u16 num;                        /* Descriptor list length. */
        u16 last;                       /* The last desc state in a list. */
 };

 struct vring_desc_extra {
-       dma_addr_t addr;                /* Descriptor DMA addr. */
-       u32 len;                        /* Descriptor length. */
        u16 flags;                      /* Descriptor flags. */
        u16 next;                       /* The next desc state in a list. */
 };

+struct vring_desc_dma {
+       dma_addr_t addr;                /* Descriptor DMA addr. */
+       u32 len;                        /* Descriptor length. */

This seems to be odd, flag should be part of dma info.

flags contains F_NEXT, that is used by detach when no dma info.

Right, so it is needed for hardening.

quoted

To reduce the changeset, I would split out next.

Do you mean split this patch set?

No, then this patch looks ok.

Thanks

Thanks

quoted

Thank