[RFC,v2,1/4] vduse: Add function to get/free the pages for reconnection
Commit Message
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.
Signed-off-by: Cindy Lu <lulu@redhat.com>
---
drivers/vdpa/vdpa_user/vduse_dev.c | 86 ++++++++++++++++++++++++++++++
1 file changed, 86 insertions(+)
Comments
On Tue, Sep 12, 2023 at 11:00 AM Cindy Lu <lulu@redhat.com> 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@redhat.com>
> ---
> 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@bytedance.com>"
> @@ -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
On Mon, Sep 18, 2023 at 4:41 PM Jason Wang <jasowang@redhat.com> wrote:
>
> On Tue, Sep 12, 2023 at 11:00 AM Cindy Lu <lulu@redhat.com> 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@redhat.com>
> > ---
> > 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@bytedance.com>"
> > @@ -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?
>
yes will remove this part
Thanks
Cindy
> > + /* memory size, here always page_size*/
> > + phys_addr_t size;
>
> If it's always PAGE_SIZE why would we have this?
will remove this
Thanks
Cindy
>
> > +};
> > +
> > 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?
>
sure will change this
Thanks
Cidny
> Thanks
>
@@ -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@bytedance.com>"
@@ -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;
+ /* memory size, here always page_size*/
+ phys_addr_t size;
+};
+
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;
+
+ info->addr = virt_to_phys(addr);
+ info->vaddr = (unsigned long)(addr);
+ info->size = PAGE_SIZE;
+ /* index is vm Offset in PAGE_SIZE */
+ info->index = 0;
+
+ /*page 1~ vq_num + 1 save the reconnect info for vqs*/
+ for (int i = 0; i < dev->vq_num + 1; i++) {
+ vq = &dev->vqs[i];
+ info = &vq->reconnect_info;
+ addr = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!addr)
+ return -1;
+
+ info->addr = virt_to_phys(addr);
+ info->vaddr = (unsigned long)(addr);
+ info->size = PAGE_SIZE;
+ info->index = i + 1;
+ }
+
+ return 0;
+}
+
+int vduse_free_reconnnect_info_mem(struct vduse_dev *dev)
+{
+ struct vdpa_reconnect_info *info;
+ struct vduse_virtqueue *vq;
+
+ info = &dev->reconnect_status;
+ free_page(info->vaddr);
+ info->size = 0;
+ info->addr = 0;
+ info->vaddr = 0;
+ for (int i = 0; i < dev->vq_num + 1; i++) {
+ vq = &dev->vqs[i];
+ info = &vq->reconnect_info;
+ free_page(info->vaddr);
+ info->size = 0;
+ info->addr = 0;
+ info->vaddr = 0;
+ }
+
+ return 0;
+}
+
static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
@@ -1390,6 +1472,8 @@ static int vduse_destroy_dev(char *name)
mutex_unlock(&dev->lock);
return -EBUSY;
}
+ vduse_free_reconnnect_info_mem(dev);
+
dev->connected = true;
mutex_unlock(&dev->lock);
@@ -1542,6 +1626,8 @@ static int vduse_create_dev(struct vduse_dev_config *config,
ret = PTR_ERR(dev->dev);
goto err_dev;
}
+
+ vduse_alloc_reconnnect_info_mem(dev);
__module_get(THIS_MODULE);
return 0;