vgsp: per-mdev emulated VRAM size (1.0 multiple mediate sizes)

- nv_vgpu_type_info/ioctl gain vram_mb; nv_vgpu_device gains fb_emul_size
  bound from the mdev type at create (default 512 MiB).
- New nvidia-vgpu-turing-1g type (1024 MiB); turing max_instances 1 -> 2;
  show_description reports the per-type framebuffer and max_instance.
- Thread fb_emul_size through GSCI fb_length/region/frtsOffset, WPR2,
  NV_PFB_PRI_MMU_LOCAL_MEMORY_RANGE, the vidmem allocator bound and the BAR1
  shadow; bar_info callback uses the per-device size.
- UNTESTED at commit time: builds clean; validation blocked by the Xid 140
  incident (reboot pending). See Handoff-vGPU-IO.md ADDENDUM 48.

1 files changed, 42 insertions, 9 deletions

diff --git a/kernel/main.c b/kernel/main.c
index 7028bdd..a5a64fd 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -112,8 +112,22 @@ static unsigned int nv_vgpu_get_available(struct mdev_type *mtype)
  */
 static ssize_t nv_vgpu_show_description(struct mdev_type *mtype, char *buf)
 {
-	return sysfs_emit(buf, "num_heads=1, frl_config=60, framebuffer=256M, "
-			       "max_resolution=5120x2880, max_instance=1\n");
+	struct nv_vgpu_type_info *info;
+	const char *name = mtype->sysfs_name;
+	u32 vram_mb = 512, max_inst = 1;
+
+	if (name && str_has_prefix(name, "nvidia-"))
+		name += strlen("nvidia-");
+	info = name ? nv_vgpu_find_type_info(name) : NULL;
+	if (info) {
+		if (info->vram_mb)
+			vram_mb = info->vram_mb;
+		if (info->max_instances)
+			max_inst = info->max_instances;
+	}
+	return sysfs_emit(buf, "num_heads=1, frl_config=60, framebuffer=%uM, "
+			       "max_resolution=5120x2880, max_instance=%u\n",
+			  vram_mb, max_inst);
 }
 
 struct mdev_driver nv_vgpu_mdev_driver = {
@@ -199,7 +213,7 @@ static NV_STATUS nv_vgpu_bar_info_callback(struct pci_dev *pdev, const NvU8 *uui
 			*size = NV_VGPU_BAR0_SIZE;  /* 16MB */
 			break;
 		case 1:
-			*size = NV_VGPU_BAR1_SIZE;  /* 256MB */
+			*size = nv_vgpu_fb_emul_size(vgpu_dev);  /* per-type FB */
 			break;
 		case 2:
 			*size = NV_VGPU_BAR2_SIZE;  /* 32MB */
@@ -370,14 +384,15 @@ EXPORT_SYMBOL(nv_vgpu_find_type_info);
 static void nv_vgpu_create_static_types(void)
 {
     int i;
-    struct nv_vgpu_type_info static_types[4] = {
-        { .name = "nvidia-vgpu-ampere", .description = "NVIDIA Ampere vGPU", .vdev_id = 0x10de2235, .pdev_id = 0x10de2235, .max_instances = 1 },
-        { .name = "nvidia-vgpu-hopper", .description = "NVIDIA Hopper vGPU", .vdev_id = 0x10de2331, .pdev_id = 0x10de2331, .max_instances = 1 },
-        { .name = "nvidia-vgpu-turing", .description = "NVIDIA Turing vGPU", .vdev_id = 0x10de1ed3, .pdev_id = 0x10de1ed3, .max_instances = 1 },
-        { .name = "nvidia-vgpu-pascal", .description = "NVIDIA Pascal vGPU", .vdev_id = 0x10de1db1, .pdev_id = 0x10de1db1, .max_instances = 1 },
+    struct nv_vgpu_type_info static_types[5] = {
+        { .name = "nvidia-vgpu-ampere", .description = "NVIDIA Ampere vGPU", .vdev_id = 0x10de2235, .pdev_id = 0x10de2235, .max_instances = 1, .vram_mb = 512 },
+        { .name = "nvidia-vgpu-hopper", .description = "NVIDIA Hopper vGPU", .vdev_id = 0x10de2331, .pdev_id = 0x10de2331, .max_instances = 1, .vram_mb = 512 },
+        { .name = "nvidia-vgpu-turing", .description = "NVIDIA Turing vGPU", .vdev_id = 0x10de1ed3, .pdev_id = 0x10de1ed3, .max_instances = 2, .vram_mb = 512 },
+        { .name = "nvidia-vgpu-turing-1g", .description = "NVIDIA Turing vGPU (1 GiB)", .vdev_id = 0x10de1ed3, .pdev_id = 0x10de1ed3, .max_instances = 2, .vram_mb = 1024 },
+        { .name = "nvidia-vgpu-pascal", .description = "NVIDIA Pascal vGPU", .vdev_id = 0x10de1db1, .pdev_id = 0x10de1db1, .max_instances = 1, .vram_mb = 512 },
     };
     
-    for (i = 0; i < 4; i++) {
+    for (i = 0; i < 5; i++) {
         nv_vgpu_register_type_info(&static_types[i]);
     }
 }
@@ -546,6 +561,24 @@ static int nv_vgpu_mdev_create(struct mdev_device *mdev)
 
  	vgpu->mdev = mdev;
  	vgpu->state = NV_VGPU_STATE_UNINITIALIZED;
+	/*
+	 * Bind the emulated FB size to this mdev's type (the type's vram_mb;
+	 * 0/absent keeps the 512 MiB default). The type dir may carry an
+	 * extra "nvidia-" prefix vs our registered names.
+	 */
+	{
+		const char *tname = mdev->type ? mdev->type->sysfs_name : NULL;
+		struct nv_vgpu_type_info *tinfo;
+
+		if (tname && str_has_prefix(tname, "nvidia-"))
+			tname += strlen("nvidia-");
+		tinfo = tname ? nv_vgpu_find_type_info(tname) : NULL;
+		vgpu->fb_emul_size = (tinfo && tinfo->vram_mb) ?
+			(u64)tinfo->vram_mb << 20 : NV_VGPU_EMUL_FB_SIZE;
+		pr_info("vgsp: mdev create: type=%s fb_emul_size=%llu MiB\n",
+			tname ? tname : "(none)",
+			(unsigned long long)(vgpu->fb_emul_size >> 20));
+	}
  	mutex_init(&vgpu->lock);
  	INIT_WORK(&vgpu->init_work, nv_vgpu_device_init_work);
  	INIT_WORK(&vgpu->cleanup_work, nv_vgpu_device_cleanup_work);