On Tue, Sep 12, 2023 at 11:00 AM Cindy Lu <lulu@xxxxxxxxxx> wrote:
>
> Add the function vduse_alloc_reconnnect_info_mem
> and vduse_alloc_reconnnect_info_mem
> In this 2 function, vduse will get/free (vq_num + 1)*page
> Page 0 will be used to save the reconnection information, The
> Userspace App will maintain this. Page 1 ~ vq_num + 1 will save
> the reconnection information for vqs.
Please explain why this is needed instead of only describing how it is
implemented. (Code can explain itself).
>
> Signed-off-by: Cindy Lu <lulu@xxxxxxxxxx>
> ---
> drivers/vdpa/vdpa_user/vduse_dev.c | 86 ++++++++++++++++++++++++++++++
> 1 file changed, 86 insertions(+)
>
> diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
> index 26b7e29cb900..4c256fa31fc4 100644
> --- a/drivers/vdpa/vdpa_user/vduse_dev.c
> +++ b/drivers/vdpa/vdpa_user/vduse_dev.c
> @@ -30,6 +30,10 @@
> #include <uapi/linux/virtio_blk.h>
> #include <linux/mod_devicetable.h>
>
> +#ifdef CONFIG_X86
> +#include <asm/set_memory.h>
> +#endif
> +
> #include "iova_domain.h"
>
> #define DRV_AUTHOR "Yongji Xie <xieyongji@xxxxxxxxxxxxx>"
> @@ -41,6 +45,23 @@
> #define VDUSE_IOVA_SIZE (128 * 1024 * 1024)
> #define VDUSE_MSG_DEFAULT_TIMEOUT 30
>
> +/* struct vdpa_reconnect_info save the page information for reconnection
> + * kernel will init these information while alloc the pages
> + * and use these information to free the pages
> + */
> +struct vdpa_reconnect_info {
> + /* Offset (within vm_file) in PAGE_SIZE,
> + * this just for check, not using
> + */
> + u32 index;
> + /* physical address for this page*/
> + phys_addr_t addr;
> + /* virtual address for this page*/
> + unsigned long vaddr;
If it could be switched by virt_to_phys() why duplicate those fields?
> + /* memory size, here always page_size*/
> + phys_addr_t size;
If it's always PAGE_SIZE why would we have this?
> +};
> +
> struct vduse_virtqueue {
> u16 index;
> u16 num_max;
> @@ -57,6 +78,7 @@ struct vduse_virtqueue {
> struct vdpa_callback cb;
> struct work_struct inject;
> struct work_struct kick;
> + struct vdpa_reconnect_info reconnect_info;
> };
>
> struct vduse_dev;
> @@ -106,6 +128,7 @@ struct vduse_dev {
> u32 vq_align;
> struct vduse_umem *umem;
> struct mutex mem_lock;
> + struct vdpa_reconnect_info reconnect_status;
> };
>
> struct vduse_dev_msg {
> @@ -1030,6 +1053,65 @@ static int vduse_dev_reg_umem(struct vduse_dev *dev,
> return ret;
> }
>
> +int vduse_alloc_reconnnect_info_mem(struct vduse_dev *dev)
> +{
> + struct vdpa_reconnect_info *info;
> + struct vduse_virtqueue *vq;
> + void *addr;
> +
> + /*page 0 is use to save status,dpdk will use this to save the information
> + *needed in reconnection,kernel don't need to maintain this
> + */
> + info = &dev->reconnect_status;
> + addr = (void *)get_zeroed_page(GFP_KERNEL);
> + if (!addr)
> + return -1;
-ENOMEM?
Thanks
