[PATCH 2/2] vfio: add edid support to mbochs sample driver

Gerd Hoffmann
2018-09-13T05:47:45Z

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
samples/vfio-mdev/mbochs.c | 54 ++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 52 insertions(+), 2 deletions(-)

diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 2535c3677c..6331871ff5 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -95,16 +95,24 @@ 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,
},
};

@@ -151,6 +159,7 @@ struct mdev_state {
u64 memsize;
struct page **pages;
pgoff_t pagecount;
+ u8 edid[512];

struct list_head dmabufs;
u32 active_id;
@@ -346,6 +355,11 @@ static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
int index;

switch (offset) {
+ case 0x000 ... 0x3ff: /* edid block */
+ if (offset + count > sizeof(mdev_state->edid))
+ goto unhandled;
+ memcpy(buf, mdev_state->edid + offset, count);
+ break;
case 0x500 ... 0x515: /* bochs dispi interface */
if (count != 2)
goto unhandled;
@@ -983,9 +997,13 @@ static int mbochs_get_irq_info(struct mdev_device *mdev,
static int mbochs_get_device_info(struct mdev_device *mdev,
struct vfio_device_info *dev_info)
{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+
dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
+ dev_info->edid_max_x = mdev_state->type->max_x;
+ dev_info->edid_max_y = mdev_state->type->max_y;
return 0;
}

@@ -1084,7 +1102,7 @@ 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);
@@ -1095,6 +1113,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
struct vfio_device_info info;

minsz = offsetofend(struct vfio_device_info, num_irqs);
+ outsz = offsetofend(struct vfio_device_info, edid_max_y);

if (copy_from_user(&info, (void __user *)arg, minsz))
return -EFAULT;
@@ -1108,7 +1127,9 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,

memcpy(&mdev_state->dev_info, &info, sizeof(info));

- if (copy_to_user((void __user *)arg, &info, minsz))
+ if (outsz > info.argsz)
+ outsz = info.argsz;
+ if (copy_to_user((void __user *)arg, &info, outsz))
return -EFAULT;

return 0;
@@ -1194,6 +1215,35 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
return mbochs_get_gfx_dmabuf(mdev, dmabuf_id);
}

+ case VFIO_DEVICE_SET_GFX_EDID:
+ {
+ struct vfio_device_set_gfx_edid *edid;
+
+ edid = kmalloc(sizeof(*edid), GFP_KERNEL);
+
+ minsz = offsetofend(struct vfio_device_set_gfx_edid,
+ edid_blob);
+
+ if (copy_from_user(edid, (void __user *)arg, minsz)) {
+ kfree(edid);
+ return -EFAULT;
+ }
+
+ if (edid->argsz < minsz ||
+ edid->edid_size > sizeof(mdev_state->edid)) {
+ kfree(edid);
+ return -EINVAL;
+ }
+
+ memset(mdev_state->edid, 0, sizeof(mdev_state->edid));
+ if (edid->link_state == VFIO_DEVICE_GFX_LINK_STATE_UP) {
+ memcpy(mdev_state->edid, edid->edid_blob, edid->edid_size);
+ }
+ kfree(edid);
+
+ return 0;
+ }
+
case VFIO_DEVICE_SET_IRQS:
return -EINVAL;

--
2.9.3