On 9/21/2018 2:00 PM, Gerd Hoffmann wrote:
> Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
> ---
>  samples/vfio-mdev/mbochs.c | 136 
> ++++++++++++++++++++++++++++++++++++++-------
>  1 file changed, 117 insertions(+), 19 deletions(-)
> 
> diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
> index 2535c3677c..ca7960adf5 100644
> --- a/samples/vfio-mdev/mbochs.c
> +++ b/samples/vfio-mdev/mbochs.c
> @@ -71,11 +71,19 @@
>  #define MBOCHS_NAME            "mbochs"
>  #define MBOCHS_CLASS_NAME      "mbochs"
>  
> +#define MBOCHS_EDID_REGION_INDEX  VFIO_PCI_NUM_REGIONS
> +#define MBOCHS_NUM_REGIONS        (MBOCHS_EDID_REGION_INDEX+1)
> +
>  #define MBOCHS_CONFIG_SPACE_SIZE  0xff
>  #define MBOCHS_MMIO_BAR_OFFSET         PAGE_SIZE
>  #define MBOCHS_MMIO_BAR_SIZE   PAGE_SIZE
> -#define MBOCHS_MEMORY_BAR_OFFSET  (MBOCHS_MMIO_BAR_OFFSET + \
> +#define MBOCHS_EDID_OFFSET     (MBOCHS_MMIO_BAR_OFFSET +     \
>                                  MBOCHS_MMIO_BAR_SIZE)
> +#define MBOCHS_EDID_SIZE       PAGE_SIZE
> +#define MBOCHS_MEMORY_BAR_OFFSET  (MBOCHS_EDID_OFFSET + \
> +                                MBOCHS_EDID_SIZE)
> +
> +#define MBOCHS_EDID_BLOB_OFFSET   (MBOCHS_EDID_SIZE/2)
>  
>  #define STORE_LE16(addr, val)        (*(u16 *)addr = val)
>  #define STORE_LE32(addr, val)        (*(u32 *)addr = val)
> @@ -95,16 +103,24 @@ MODULE_PARM_DESC(mem, "megabytes available to " 
> MBOCHS_NAME " devices");
>  static const struct mbochs_type {
>       const char *name;
>       u32 mbytes;
> +     u32 max_x;
> +     u32 max_y;
>  } mbochs_types[] = {
>       {
>               .name   = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
>               .mbytes = 4,
> +             .max_x  = 800,
> +             .max_y  = 600,
>       }, {
>               .name   = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
>               .mbytes = 16,
> +             .max_x  = 1920,
> +             .max_y  = 1440,
>       }, {
>               .name   = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
>               .mbytes = 64,
> +             .max_x  = 0,
> +             .max_y  = 0,
>       },
>  };
>  
> @@ -115,6 +131,11 @@ static struct cdev       mbochs_cdev;
>  static struct device mbochs_dev;
>  static int           mbochs_used_mbytes;
>  
> +struct vfio_region_info_ext {
> +     struct vfio_region_info          base;
> +     struct vfio_region_info_cap_type type;
> +};
> +
>  struct mbochs_mode {
>       u32 drm_format;
>       u32 bytepp;
> @@ -144,13 +165,14 @@ struct mdev_state {
>       u32 memory_bar_mask;
>       struct mutex ops_lock;
>       struct mdev_device *mdev;
> -     struct vfio_device_info dev_info;
>  
>       const struct mbochs_type *type;
>       u16 vbe[VBE_DISPI_INDEX_COUNT];
>       u64 memsize;
>       struct page **pages;
>       pgoff_t pagecount;
> +     struct vfio_region_gfx_edid edid_regs;
> +     u8 edid_blob[0x400];
>  
>       struct list_head dmabufs;
>       u32 active_id;
> @@ -342,10 +364,20 @@ static void handle_mmio_read(struct mdev_state 
> *mdev_state, u16 offset,
>                            char *buf, u32 count)
>  {
>       struct device *dev = mdev_dev(mdev_state->mdev);
> +     struct vfio_region_gfx_edid *edid;
>       u16 reg16 = 0;
>       int index;
>  
>       switch (offset) {
> +     case 0x000 ... 0x3ff: /* edid block */
> +             edid = &mdev_state->edid_regs;
> +             if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP ||
> +                 offset >= edid->edid_size) {
> +                     memset(buf, 0, count);
> +                     break;
> +             }
> +             memcpy(buf, mdev_state->edid_blob + offset, count);
> +             break;
>       case 0x500 ... 0x515: /* bochs dispi interface */
>               if (count != 2)
>                       goto unhandled;
> @@ -365,6 +397,44 @@ static void handle_mmio_read(struct mdev_state 
> *mdev_state, u16 offset,
>       }
>  }
>  
> +static void handle_edid_regs(struct mdev_state *mdev_state, u16 offset,
> +                          char *buf, u32 count, bool is_write)
> +{
> +     char *regs = (void *)&mdev_state->edid_regs;
> +
> +     if (offset + count > sizeof(mdev_state->edid_regs))
> +             return;
> +     if (count != 4)
> +             return;
> +     if (offset % 4)
> +             return;
> +
> +     if (is_write) {
> +             switch (offset) {
> +             case offsetof(struct vfio_region_gfx_edid, link_state):
> +             case offsetof(struct vfio_region_gfx_edid, edid_size):
> +                     memcpy(regs + offset, buf, count);
> +                     break;
> +             default:
> +                     /* read-only regs */
> +                     break;
> +             }
> +     } else {
> +             memcpy(buf, regs + offset, count);
> +     }
> +}
> +
> +static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
> +                          char *buf, u32 count, bool is_write)
> +{
> +     if (offset + count > mdev_state->edid_regs.edid_max_size)
> +             return;
> +     if (is_write)
> +             memcpy(mdev_state->edid_blob + offset, buf, count);
> +     else
> +             memcpy(buf, mdev_state->edid_blob + offset, count);
> +}
> +
>  static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
>                          loff_t pos, bool is_write)
>  {
> @@ -384,13 +454,25 @@ static ssize_t mdev_access(struct mdev_device *mdev, 
> char *buf, size_t count,
>                       memcpy(buf, (mdev_state->vconfig + pos), count);
>  
>       } else if (pos >= MBOCHS_MMIO_BAR_OFFSET &&
> -                pos + count <= MBOCHS_MEMORY_BAR_OFFSET) {
> +                pos + count <= (MBOCHS_MMIO_BAR_OFFSET +
> +                                MBOCHS_MMIO_BAR_SIZE)) {
>               pos -= MBOCHS_MMIO_BAR_OFFSET;
>               if (is_write)
>                       handle_mmio_write(mdev_state, pos, buf, count);
>               else
>                       handle_mmio_read(mdev_state, pos, buf, count);
>  
> +     } else if (pos >= MBOCHS_EDID_OFFSET &&
> +                pos + count <= (MBOCHS_EDID_OFFSET +
> +                                MBOCHS_EDID_SIZE)) {
> +             pos -= MBOCHS_EDID_OFFSET;
> +             if (pos < MBOCHS_EDID_BLOB_OFFSET) {
> +                     handle_edid_regs(mdev_state, pos, buf, count, is_write);
> +             } else {
> +                     pos -= MBOCHS_EDID_BLOB_OFFSET;
> +                     handle_edid_blob(mdev_state, pos, buf, count, is_write);
> +             }
> +
>       } else if (pos >= MBOCHS_MEMORY_BAR_OFFSET &&
>                  pos + count <=
>                  MBOCHS_MEMORY_BAR_OFFSET + mdev_state->memsize) {
> @@ -471,6 +553,10 @@ static int mbochs_create(struct kobject *kobj, struct 
> mdev_device *mdev)
>       mdev_state->next_id = 1;
>  
>       mdev_state->type = type;
> +     mdev_state->edid_regs.max_xres = type->max_x;
> +     mdev_state->edid_regs.max_yres = type->max_y;
> +     mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
> +     mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
>       mbochs_create_config_space(mdev_state);
>       mbochs_reset(mdev);
>  
> @@ -932,16 +1018,16 @@ static int mbochs_dmabuf_export(struct mbochs_dmabuf 
> *dmabuf)
>  }
>  
>  static int mbochs_get_region_info(struct mdev_device *mdev,
> -                               struct vfio_region_info *region_info,
> -                               u16 *cap_type_id, void **cap_type)
> +                               struct vfio_region_info_ext *ext)
>  {
> +     struct vfio_region_info *region_info = &ext->base;
>       struct mdev_state *mdev_state;
>  
>       mdev_state = mdev_get_drvdata(mdev);
>       if (!mdev_state)
>               return -EINVAL;
>  
> -     if (region_info->index >= VFIO_PCI_NUM_REGIONS)
> +     if (region_info->index >= MBOCHS_NUM_REGIONS)
>               return -EINVAL;
>  
>       switch (region_info->index) {
> @@ -964,6 +1050,20 @@ static int mbochs_get_region_info(struct mdev_device 
> *mdev,
>               region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
>                                      VFIO_REGION_INFO_FLAG_WRITE);
>               break;
> +     case MBOCHS_EDID_REGION_INDEX:
> +             ext->base.argsz = sizeof(*ext);
> +             ext->base.offset = MBOCHS_EDID_OFFSET;
> +             ext->base.size = MBOCHS_EDID_SIZE;
> +             ext->base.flags = (VFIO_REGION_INFO_FLAG_READ  |
> +                                VFIO_REGION_INFO_FLAG_WRITE |
> +                                VFIO_REGION_INFO_FLAG_CAPS);

Any reason to not to use _MMAP flag?
How would QEMU side code read this region? will it be always trapped?
If vendor driver sets _MMAP flag, will QEMU side handle that case as well?
I think since its blob, edid could be read by QEMU using one memcpy
rather than adding multiple memcpy of 4 or 8 bytes.

Thanks,
Kirti

> +             ext->base.cap_offset = offsetof(typeof(*ext), type);
> +             ext->type.header.id = VFIO_REGION_INFO_CAP_TYPE;
> +             ext->type.header.version = 1;
> +             ext->type.header.next = 0;
> +             ext->type.type = VFIO_REGION_TYPE_GFX;
> +             ext->type.subtype = VFIO_REGION_SUBTYPE_GFX_EDID;
> +             break;
>       default:
>               region_info->size   = 0;
>               region_info->offset = 0;
> @@ -984,7 +1084,7 @@ static int mbochs_get_device_info(struct mdev_device 
> *mdev,
>                                 struct vfio_device_info *dev_info)
>  {
>       dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
> -     dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
> +     dev_info->num_regions = MBOCHS_NUM_REGIONS;
>       dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
>       return 0;
>  }
> @@ -1084,7 +1184,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, 
> unsigned int cmd,
>                       unsigned long arg)
>  {
>       int ret = 0;
> -     unsigned long minsz;
> +     unsigned long minsz, outsz;
>       struct mdev_state *mdev_state;
>  
>       mdev_state = mdev_get_drvdata(mdev);
> @@ -1106,8 +1206,6 @@ static long mbochs_ioctl(struct mdev_device *mdev, 
> unsigned int cmd,
>               if (ret)
>                       return ret;
>  
> -             memcpy(&mdev_state->dev_info, &info, sizeof(info));
> -
>               if (copy_to_user((void __user *)arg, &info, minsz))
>                       return -EFAULT;
>  
> @@ -1115,24 +1213,24 @@ static long mbochs_ioctl(struct mdev_device *mdev, 
> unsigned int cmd,
>       }
>       case VFIO_DEVICE_GET_REGION_INFO:
>       {
> -             struct vfio_region_info info;
> -             u16 cap_type_id = 0;
> -             void *cap_type = NULL;
> +             struct vfio_region_info_ext info;
>  
> -             minsz = offsetofend(struct vfio_region_info, offset);
> +             minsz = offsetofend(typeof(info), base.offset);
>  
>               if (copy_from_user(&info, (void __user *)arg, minsz))
>                       return -EFAULT;
>  
> -             if (info.argsz < minsz)
> +             outsz = info.base.argsz;
> +             if (outsz < minsz)
> +                     return -EINVAL;
> +             if (outsz > sizeof(info))
>                       return -EINVAL;
>  
> -             ret = mbochs_get_region_info(mdev, &info, &cap_type_id,
> -                                        &cap_type);
> +             ret = mbochs_get_region_info(mdev, &info);
>               if (ret)
>                       return ret;
>  
> -             if (copy_to_user((void __user *)arg, &info, minsz))
> +             if (copy_to_user((void __user *)arg, &info, outsz))
>                       return -EFAULT;
>  
>               return 0;
> @@ -1148,7 +1246,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, 
> unsigned int cmd,
>                       return -EFAULT;
>  
>               if ((info.argsz < minsz) ||
> -                 (info.index >= mdev_state->dev_info.num_irqs))
> +                 (info.index >= VFIO_PCI_NUM_IRQS))
>                       return -EINVAL;
>  
>               ret = mbochs_get_irq_info(mdev, &info);
> 

Reply via email to