1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2012, Microsoft Corporation. 4 * 5 * Author: 6 * Haiyang Zhang <haiyangz@microsoft.com> 7 */ 8 9 /* 10 * Hyper-V Synthetic Video Frame Buffer Driver 11 * 12 * This is the driver for the Hyper-V Synthetic Video, which supports 13 * screen resolution up to Full HD 1920x1080 with 32 bit color on Windows 14 * Server 2012, and 1600x1200 with 16 bit color on Windows Server 2008 R2 15 * or earlier. 16 * 17 * It also solves the double mouse cursor issue of the emulated video mode. 18 * 19 * The default screen resolution is 1152x864, which may be changed by a 20 * kernel parameter: 21 * video=hyperv_fb:<width>x<height> 22 * For example: video=hyperv_fb:1280x1024 23 * 24 * Portrait orientation is also supported: 25 * For example: video=hyperv_fb:864x1152 26 * 27 * When a Windows 10 RS5+ host is used, the virtual machine screen 28 * resolution is obtained from the host. The "video=hyperv_fb" option is 29 * not needed, but still can be used to overwrite what the host specifies. 30 * The VM resolution on the host could be set by executing the powershell 31 * "set-vmvideo" command. For example 32 * set-vmvideo -vmname name -horizontalresolution:1920 \ 33 * -verticalresolution:1200 -resolutiontype single 34 * 35 * Gen 1 VMs also support direct using VM's physical memory for framebuffer. 36 * It could improve the efficiency and performance for framebuffer and VM. 37 * This requires to allocate contiguous physical memory from Linux kernel's 38 * CMA memory allocator. To enable this, supply a kernel parameter to give 39 * enough memory space to CMA allocator for framebuffer. For example: 40 * cma=130m 41 * This gives 130MB memory to CMA allocator that can be allocated to 42 * framebuffer. For reference, 8K resolution (7680x4320) takes about 43 * 127MB memory. 44 */ 45 46 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 47 48 #include <linux/aperture.h> 49 #include <linux/module.h> 50 #include <linux/kernel.h> 51 #include <linux/screen_info.h> 52 #include <linux/vmalloc.h> 53 #include <linux/init.h> 54 #include <linux/completion.h> 55 #include <linux/fb.h> 56 #include <linux/pci.h> 57 #include <linux/panic_notifier.h> 58 #include <linux/efi.h> 59 #include <linux/console.h> 60 61 #include <linux/hyperv.h> 62 63 /* Hyper-V Synthetic Video Protocol definitions and structures */ 64 #define MAX_VMBUS_PKT_SIZE 0x4000 65 66 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major)) 67 /* Support for VERSION_WIN7 is removed. #define is retained for reference. */ 68 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0) 69 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2) 70 #define SYNTHVID_VERSION_WIN10 SYNTHVID_VERSION(3, 5) 71 72 #define SYNTHVID_VER_GET_MAJOR(ver) (ver & 0x0000ffff) 73 #define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16) 74 75 #define SYNTHVID_DEPTH_WIN8 32 76 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024) 77 78 enum pipe_msg_type { 79 PIPE_MSG_INVALID, 80 PIPE_MSG_DATA, 81 PIPE_MSG_MAX 82 }; 83 84 struct pipe_msg_hdr { 85 u32 type; 86 u32 size; /* size of message after this field */ 87 } __packed; 88 89 90 enum synthvid_msg_type { 91 SYNTHVID_ERROR = 0, 92 SYNTHVID_VERSION_REQUEST = 1, 93 SYNTHVID_VERSION_RESPONSE = 2, 94 SYNTHVID_VRAM_LOCATION = 3, 95 SYNTHVID_VRAM_LOCATION_ACK = 4, 96 SYNTHVID_SITUATION_UPDATE = 5, 97 SYNTHVID_SITUATION_UPDATE_ACK = 6, 98 SYNTHVID_POINTER_POSITION = 7, 99 SYNTHVID_POINTER_SHAPE = 8, 100 SYNTHVID_FEATURE_CHANGE = 9, 101 SYNTHVID_DIRT = 10, 102 SYNTHVID_RESOLUTION_REQUEST = 13, 103 SYNTHVID_RESOLUTION_RESPONSE = 14, 104 105 SYNTHVID_MAX = 15 106 }; 107 108 #define SYNTHVID_EDID_BLOCK_SIZE 128 109 #define SYNTHVID_MAX_RESOLUTION_COUNT 64 110 111 struct hvd_screen_info { 112 u16 width; 113 u16 height; 114 } __packed; 115 116 struct synthvid_msg_hdr { 117 u32 type; 118 u32 size; /* size of this header + payload after this field*/ 119 } __packed; 120 121 struct synthvid_version_req { 122 u32 version; 123 } __packed; 124 125 struct synthvid_version_resp { 126 u32 version; 127 u8 is_accepted; 128 u8 max_video_outputs; 129 } __packed; 130 131 struct synthvid_supported_resolution_req { 132 u8 maximum_resolution_count; 133 } __packed; 134 135 struct synthvid_supported_resolution_resp { 136 u8 edid_block[SYNTHVID_EDID_BLOCK_SIZE]; 137 u8 resolution_count; 138 u8 default_resolution_index; 139 u8 is_standard; 140 struct hvd_screen_info 141 supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT]; 142 } __packed; 143 144 struct synthvid_vram_location { 145 u64 user_ctx; 146 u8 is_vram_gpa_specified; 147 u64 vram_gpa; 148 } __packed; 149 150 struct synthvid_vram_location_ack { 151 u64 user_ctx; 152 } __packed; 153 154 struct video_output_situation { 155 u8 active; 156 u32 vram_offset; 157 u8 depth_bits; 158 u32 width_pixels; 159 u32 height_pixels; 160 u32 pitch_bytes; 161 } __packed; 162 163 struct synthvid_situation_update { 164 u64 user_ctx; 165 u8 video_output_count; 166 struct video_output_situation video_output[1]; 167 } __packed; 168 169 struct synthvid_situation_update_ack { 170 u64 user_ctx; 171 } __packed; 172 173 struct synthvid_pointer_position { 174 u8 is_visible; 175 u8 video_output; 176 s32 image_x; 177 s32 image_y; 178 } __packed; 179 180 181 #define CURSOR_MAX_X 96 182 #define CURSOR_MAX_Y 96 183 #define CURSOR_ARGB_PIXEL_SIZE 4 184 #define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE) 185 #define CURSOR_COMPLETE (-1) 186 187 struct synthvid_pointer_shape { 188 u8 part_idx; 189 u8 is_argb; 190 u32 width; /* CURSOR_MAX_X at most */ 191 u32 height; /* CURSOR_MAX_Y at most */ 192 u32 hot_x; /* hotspot relative to upper-left of pointer image */ 193 u32 hot_y; 194 u8 data[4]; 195 } __packed; 196 197 struct synthvid_feature_change { 198 u8 is_dirt_needed; 199 u8 is_ptr_pos_needed; 200 u8 is_ptr_shape_needed; 201 u8 is_situ_needed; 202 } __packed; 203 204 struct rect { 205 s32 x1, y1; /* top left corner */ 206 s32 x2, y2; /* bottom right corner, exclusive */ 207 } __packed; 208 209 struct synthvid_dirt { 210 u8 video_output; 211 u8 dirt_count; 212 struct rect rect[1]; 213 } __packed; 214 215 struct synthvid_msg { 216 struct pipe_msg_hdr pipe_hdr; 217 struct synthvid_msg_hdr vid_hdr; 218 union { 219 struct synthvid_version_req ver_req; 220 struct synthvid_version_resp ver_resp; 221 struct synthvid_vram_location vram; 222 struct synthvid_vram_location_ack vram_ack; 223 struct synthvid_situation_update situ; 224 struct synthvid_situation_update_ack situ_ack; 225 struct synthvid_pointer_position ptr_pos; 226 struct synthvid_pointer_shape ptr_shape; 227 struct synthvid_feature_change feature_chg; 228 struct synthvid_dirt dirt; 229 struct synthvid_supported_resolution_req resolution_req; 230 struct synthvid_supported_resolution_resp resolution_resp; 231 }; 232 } __packed; 233 234 235 /* FB driver definitions and structures */ 236 #define HVFB_WIDTH 1152 /* default screen width */ 237 #define HVFB_HEIGHT 864 /* default screen height */ 238 #define HVFB_WIDTH_MIN 640 239 #define HVFB_HEIGHT_MIN 480 240 241 #define RING_BUFSIZE (256 * 1024) 242 #define VSP_TIMEOUT (10 * HZ) 243 #define HVFB_UPDATE_DELAY (HZ / 20) 244 #define HVFB_ONDEMAND_THROTTLE (HZ / 20) 245 246 struct hvfb_par { 247 struct fb_info *info; 248 struct resource *mem; 249 bool fb_ready; /* fb device is ready */ 250 struct completion wait; 251 u32 synthvid_version; 252 253 struct delayed_work dwork; 254 bool update; 255 bool update_saved; /* The value of 'update' before hibernation */ 256 257 u32 pseudo_palette[16]; 258 u8 init_buf[MAX_VMBUS_PKT_SIZE]; 259 u8 recv_buf[MAX_VMBUS_PKT_SIZE]; 260 261 /* If true, the VSC notifies the VSP on every framebuffer change */ 262 bool synchronous_fb; 263 264 /* If true, need to copy from deferred IO mem to framebuffer mem */ 265 bool need_docopy; 266 267 struct notifier_block hvfb_panic_nb; 268 269 /* Memory for deferred IO and frame buffer itself */ 270 unsigned char *dio_vp; 271 unsigned char *mmio_vp; 272 phys_addr_t mmio_pp; 273 274 /* Dirty rectangle, protected by delayed_refresh_lock */ 275 int x1, y1, x2, y2; 276 bool delayed_refresh; 277 spinlock_t delayed_refresh_lock; 278 }; 279 280 static uint screen_width = HVFB_WIDTH; 281 static uint screen_height = HVFB_HEIGHT; 282 static uint screen_depth; 283 static uint screen_fb_size; 284 static uint dio_fb_size; /* FB size for deferred IO */ 285 286 /* Send message to Hyper-V host */ 287 static inline int synthvid_send(struct hv_device *hdev, 288 struct synthvid_msg *msg) 289 { 290 static atomic64_t request_id = ATOMIC64_INIT(0); 291 int ret; 292 293 msg->pipe_hdr.type = PIPE_MSG_DATA; 294 msg->pipe_hdr.size = msg->vid_hdr.size; 295 296 ret = vmbus_sendpacket(hdev->channel, msg, 297 msg->vid_hdr.size + sizeof(struct pipe_msg_hdr), 298 atomic64_inc_return(&request_id), 299 VM_PKT_DATA_INBAND, 0); 300 301 if (ret) 302 pr_err_ratelimited("Unable to send packet via vmbus; error %d\n", ret); 303 304 return ret; 305 } 306 307 308 /* Send screen resolution info to host */ 309 static int synthvid_send_situ(struct hv_device *hdev) 310 { 311 struct fb_info *info = hv_get_drvdata(hdev); 312 struct synthvid_msg msg; 313 314 if (!info) 315 return -ENODEV; 316 317 memset(&msg, 0, sizeof(struct synthvid_msg)); 318 319 msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE; 320 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 321 sizeof(struct synthvid_situation_update); 322 msg.situ.user_ctx = 0; 323 msg.situ.video_output_count = 1; 324 msg.situ.video_output[0].active = 1; 325 msg.situ.video_output[0].vram_offset = 0; 326 msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel; 327 msg.situ.video_output[0].width_pixels = info->var.xres; 328 msg.situ.video_output[0].height_pixels = info->var.yres; 329 msg.situ.video_output[0].pitch_bytes = info->fix.line_length; 330 331 synthvid_send(hdev, &msg); 332 333 return 0; 334 } 335 336 /* Send mouse pointer info to host */ 337 static int synthvid_send_ptr(struct hv_device *hdev) 338 { 339 struct synthvid_msg msg; 340 341 memset(&msg, 0, sizeof(struct synthvid_msg)); 342 msg.vid_hdr.type = SYNTHVID_POINTER_POSITION; 343 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 344 sizeof(struct synthvid_pointer_position); 345 msg.ptr_pos.is_visible = 1; 346 msg.ptr_pos.video_output = 0; 347 msg.ptr_pos.image_x = 0; 348 msg.ptr_pos.image_y = 0; 349 synthvid_send(hdev, &msg); 350 351 memset(&msg, 0, sizeof(struct synthvid_msg)); 352 msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE; 353 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 354 sizeof(struct synthvid_pointer_shape); 355 msg.ptr_shape.part_idx = CURSOR_COMPLETE; 356 msg.ptr_shape.is_argb = 1; 357 msg.ptr_shape.width = 1; 358 msg.ptr_shape.height = 1; 359 msg.ptr_shape.hot_x = 0; 360 msg.ptr_shape.hot_y = 0; 361 msg.ptr_shape.data[0] = 0; 362 msg.ptr_shape.data[1] = 1; 363 msg.ptr_shape.data[2] = 1; 364 msg.ptr_shape.data[3] = 1; 365 synthvid_send(hdev, &msg); 366 367 return 0; 368 } 369 370 /* Send updated screen area (dirty rectangle) location to host */ 371 static int 372 synthvid_update(struct fb_info *info, int x1, int y1, int x2, int y2) 373 { 374 struct hv_device *hdev = device_to_hv_device(info->device); 375 struct synthvid_msg msg; 376 377 memset(&msg, 0, sizeof(struct synthvid_msg)); 378 if (x2 == INT_MAX) 379 x2 = info->var.xres; 380 if (y2 == INT_MAX) 381 y2 = info->var.yres; 382 383 msg.vid_hdr.type = SYNTHVID_DIRT; 384 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 385 sizeof(struct synthvid_dirt); 386 msg.dirt.video_output = 0; 387 msg.dirt.dirt_count = 1; 388 msg.dirt.rect[0].x1 = (x1 > x2) ? 0 : x1; 389 msg.dirt.rect[0].y1 = (y1 > y2) ? 0 : y1; 390 msg.dirt.rect[0].x2 = 391 (x2 < x1 || x2 > info->var.xres) ? info->var.xres : x2; 392 msg.dirt.rect[0].y2 = 393 (y2 < y1 || y2 > info->var.yres) ? info->var.yres : y2; 394 395 synthvid_send(hdev, &msg); 396 397 return 0; 398 } 399 400 static void hvfb_docopy(struct hvfb_par *par, 401 unsigned long offset, 402 unsigned long size) 403 { 404 if (!par || !par->mmio_vp || !par->dio_vp || !par->fb_ready || 405 size == 0 || offset >= dio_fb_size) 406 return; 407 408 if (offset + size > dio_fb_size) 409 size = dio_fb_size - offset; 410 411 memcpy(par->mmio_vp + offset, par->dio_vp + offset, size); 412 } 413 414 /* Deferred IO callback */ 415 static void synthvid_deferred_io(struct fb_info *p, struct list_head *pagereflist) 416 { 417 struct hvfb_par *par = p->par; 418 struct fb_deferred_io_pageref *pageref; 419 unsigned long start, end; 420 int y1, y2, miny, maxy; 421 422 miny = INT_MAX; 423 maxy = 0; 424 425 /* 426 * Merge dirty pages. It is possible that last page cross 427 * over the end of frame buffer row yres. This is taken care of 428 * in synthvid_update function by clamping the y2 429 * value to yres. 430 */ 431 list_for_each_entry(pageref, pagereflist, list) { 432 start = pageref->offset; 433 end = start + PAGE_SIZE - 1; 434 y1 = start / p->fix.line_length; 435 y2 = end / p->fix.line_length; 436 miny = min_t(int, miny, y1); 437 maxy = max_t(int, maxy, y2); 438 439 /* Copy from dio space to mmio address */ 440 if (par->fb_ready && par->need_docopy) 441 hvfb_docopy(par, start, PAGE_SIZE); 442 } 443 444 if (par->fb_ready && par->update) 445 synthvid_update(p, 0, miny, p->var.xres, maxy + 1); 446 } 447 448 static struct fb_deferred_io synthvid_defio = { 449 .delay = HZ / 20, 450 .deferred_io = synthvid_deferred_io, 451 }; 452 453 /* 454 * Actions on received messages from host: 455 * Complete the wait event. 456 * Or, reply with screen and cursor info. 457 */ 458 static void synthvid_recv_sub(struct hv_device *hdev) 459 { 460 struct fb_info *info = hv_get_drvdata(hdev); 461 struct hvfb_par *par; 462 struct synthvid_msg *msg; 463 464 if (!info) 465 return; 466 467 par = info->par; 468 msg = (struct synthvid_msg *)par->recv_buf; 469 470 /* Complete the wait event */ 471 if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE || 472 msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE || 473 msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) { 474 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE); 475 complete(&par->wait); 476 return; 477 } 478 479 /* Reply with screen and cursor info */ 480 if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) { 481 if (par->fb_ready) { 482 synthvid_send_ptr(hdev); 483 synthvid_send_situ(hdev); 484 } 485 486 par->update = msg->feature_chg.is_dirt_needed; 487 if (par->update) 488 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY); 489 } 490 } 491 492 /* Receive callback for messages from the host */ 493 static void synthvid_receive(void *ctx) 494 { 495 struct hv_device *hdev = ctx; 496 struct fb_info *info = hv_get_drvdata(hdev); 497 struct hvfb_par *par; 498 struct synthvid_msg *recv_buf; 499 u32 bytes_recvd; 500 u64 req_id; 501 int ret; 502 503 if (!info) 504 return; 505 506 par = info->par; 507 recv_buf = (struct synthvid_msg *)par->recv_buf; 508 509 do { 510 ret = vmbus_recvpacket(hdev->channel, recv_buf, 511 MAX_VMBUS_PKT_SIZE, 512 &bytes_recvd, &req_id); 513 if (bytes_recvd > 0 && 514 recv_buf->pipe_hdr.type == PIPE_MSG_DATA) 515 synthvid_recv_sub(hdev); 516 } while (bytes_recvd > 0 && ret == 0); 517 } 518 519 /* Check if the ver1 version is equal or greater than ver2 */ 520 static inline bool synthvid_ver_ge(u32 ver1, u32 ver2) 521 { 522 if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) || 523 (SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) && 524 SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2))) 525 return true; 526 527 return false; 528 } 529 530 /* Check synthetic video protocol version with the host */ 531 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver) 532 { 533 struct fb_info *info = hv_get_drvdata(hdev); 534 struct hvfb_par *par = info->par; 535 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf; 536 int ret = 0; 537 unsigned long t; 538 539 memset(msg, 0, sizeof(struct synthvid_msg)); 540 msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST; 541 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 542 sizeof(struct synthvid_version_req); 543 msg->ver_req.version = ver; 544 synthvid_send(hdev, msg); 545 546 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT); 547 if (!t) { 548 pr_err("Time out on waiting version response\n"); 549 ret = -ETIMEDOUT; 550 goto out; 551 } 552 if (!msg->ver_resp.is_accepted) { 553 ret = -ENODEV; 554 goto out; 555 } 556 557 par->synthvid_version = ver; 558 pr_info("Synthvid Version major %d, minor %d\n", 559 SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver)); 560 561 out: 562 return ret; 563 } 564 565 /* Get current resolution from the host */ 566 static int synthvid_get_supported_resolution(struct hv_device *hdev) 567 { 568 struct fb_info *info = hv_get_drvdata(hdev); 569 struct hvfb_par *par = info->par; 570 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf; 571 int ret = 0; 572 unsigned long t; 573 u8 index; 574 575 memset(msg, 0, sizeof(struct synthvid_msg)); 576 msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST; 577 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 578 sizeof(struct synthvid_supported_resolution_req); 579 580 msg->resolution_req.maximum_resolution_count = 581 SYNTHVID_MAX_RESOLUTION_COUNT; 582 synthvid_send(hdev, msg); 583 584 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT); 585 if (!t) { 586 pr_err("Time out on waiting resolution response\n"); 587 ret = -ETIMEDOUT; 588 goto out; 589 } 590 591 if (msg->resolution_resp.resolution_count == 0) { 592 pr_err("No supported resolutions\n"); 593 ret = -ENODEV; 594 goto out; 595 } 596 597 index = msg->resolution_resp.default_resolution_index; 598 if (index >= msg->resolution_resp.resolution_count) { 599 pr_err("Invalid resolution index: %d\n", index); 600 ret = -ENODEV; 601 goto out; 602 } 603 604 screen_width = 605 msg->resolution_resp.supported_resolution[index].width; 606 screen_height = 607 msg->resolution_resp.supported_resolution[index].height; 608 609 out: 610 return ret; 611 } 612 613 /* Connect to VSP (Virtual Service Provider) on host */ 614 static int synthvid_connect_vsp(struct hv_device *hdev) 615 { 616 struct fb_info *info = hv_get_drvdata(hdev); 617 struct hvfb_par *par = info->par; 618 int ret; 619 620 ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE, 621 NULL, 0, synthvid_receive, hdev); 622 if (ret) { 623 pr_err("Unable to open vmbus channel\n"); 624 return ret; 625 } 626 627 /* Negotiate the protocol version with host */ 628 switch (vmbus_proto_version) { 629 case VERSION_WIN10: 630 case VERSION_WIN10_V5: 631 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10); 632 if (!ret) 633 break; 634 fallthrough; 635 case VERSION_WIN8: 636 case VERSION_WIN8_1: 637 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8); 638 break; 639 default: 640 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10); 641 break; 642 } 643 644 if (ret) { 645 pr_err("Synthetic video device version not accepted\n"); 646 goto error; 647 } 648 649 screen_depth = SYNTHVID_DEPTH_WIN8; 650 if (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10)) { 651 ret = synthvid_get_supported_resolution(hdev); 652 if (ret) 653 pr_info("Failed to get supported resolution from host, use default\n"); 654 } 655 656 screen_fb_size = hdev->channel->offermsg.offer. 657 mmio_megabytes * 1024 * 1024; 658 659 return 0; 660 661 error: 662 vmbus_close(hdev->channel); 663 return ret; 664 } 665 666 /* Send VRAM and Situation messages to the host */ 667 static int synthvid_send_config(struct hv_device *hdev) 668 { 669 struct fb_info *info = hv_get_drvdata(hdev); 670 struct hvfb_par *par = info->par; 671 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf; 672 int ret = 0; 673 unsigned long t; 674 675 /* Send VRAM location */ 676 memset(msg, 0, sizeof(struct synthvid_msg)); 677 msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION; 678 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 679 sizeof(struct synthvid_vram_location); 680 msg->vram.user_ctx = msg->vram.vram_gpa = par->mmio_pp; 681 msg->vram.is_vram_gpa_specified = 1; 682 synthvid_send(hdev, msg); 683 684 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT); 685 if (!t) { 686 pr_err("Time out on waiting vram location ack\n"); 687 ret = -ETIMEDOUT; 688 goto out; 689 } 690 if (msg->vram_ack.user_ctx != par->mmio_pp) { 691 pr_err("Unable to set VRAM location\n"); 692 ret = -ENODEV; 693 goto out; 694 } 695 696 /* Send pointer and situation update */ 697 synthvid_send_ptr(hdev); 698 synthvid_send_situ(hdev); 699 700 out: 701 return ret; 702 } 703 704 705 /* 706 * Delayed work callback: 707 * It is scheduled to call whenever update request is received and it has 708 * not been called in last HVFB_ONDEMAND_THROTTLE time interval. 709 */ 710 static void hvfb_update_work(struct work_struct *w) 711 { 712 struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work); 713 struct fb_info *info = par->info; 714 unsigned long flags; 715 int x1, x2, y1, y2; 716 int j; 717 718 spin_lock_irqsave(&par->delayed_refresh_lock, flags); 719 /* Reset the request flag */ 720 par->delayed_refresh = false; 721 722 /* Store the dirty rectangle to local variables */ 723 x1 = par->x1; 724 x2 = par->x2; 725 y1 = par->y1; 726 y2 = par->y2; 727 728 /* Clear dirty rectangle */ 729 par->x1 = par->y1 = INT_MAX; 730 par->x2 = par->y2 = 0; 731 732 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags); 733 734 if (x1 > info->var.xres || x2 > info->var.xres || 735 y1 > info->var.yres || y2 > info->var.yres || x2 <= x1) 736 return; 737 738 /* Copy the dirty rectangle to frame buffer memory */ 739 if (par->need_docopy) 740 for (j = y1; j < y2; j++) 741 hvfb_docopy(par, 742 j * info->fix.line_length + 743 (x1 * screen_depth / 8), 744 (x2 - x1) * screen_depth / 8); 745 746 /* Refresh */ 747 if (par->fb_ready && par->update) 748 synthvid_update(info, x1, y1, x2, y2); 749 } 750 751 /* 752 * Control the on-demand refresh frequency. It schedules a delayed 753 * screen update if it has not yet. 754 */ 755 static void hvfb_ondemand_refresh_throttle(struct hvfb_par *par, 756 int x1, int y1, int w, int h) 757 { 758 unsigned long flags; 759 int x2 = x1 + w; 760 int y2 = y1 + h; 761 762 spin_lock_irqsave(&par->delayed_refresh_lock, flags); 763 764 /* Merge dirty rectangle */ 765 par->x1 = min_t(int, par->x1, x1); 766 par->y1 = min_t(int, par->y1, y1); 767 par->x2 = max_t(int, par->x2, x2); 768 par->y2 = max_t(int, par->y2, y2); 769 770 /* Schedule a delayed screen update if not yet */ 771 if (par->delayed_refresh == false) { 772 schedule_delayed_work(&par->dwork, 773 HVFB_ONDEMAND_THROTTLE); 774 par->delayed_refresh = true; 775 } 776 777 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags); 778 } 779 780 static int hvfb_on_panic(struct notifier_block *nb, 781 unsigned long e, void *p) 782 { 783 struct hv_device *hdev; 784 struct hvfb_par *par; 785 struct fb_info *info; 786 787 par = container_of(nb, struct hvfb_par, hvfb_panic_nb); 788 info = par->info; 789 hdev = device_to_hv_device(info->device); 790 791 if (hv_ringbuffer_spinlock_busy(hdev->channel)) 792 return NOTIFY_DONE; 793 794 par->synchronous_fb = true; 795 if (par->need_docopy) 796 hvfb_docopy(par, 0, dio_fb_size); 797 synthvid_update(info, 0, 0, INT_MAX, INT_MAX); 798 799 return NOTIFY_DONE; 800 } 801 802 /* Framebuffer operation handlers */ 803 804 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) 805 { 806 if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN || 807 var->xres > screen_width || var->yres > screen_height || 808 var->bits_per_pixel != screen_depth) 809 return -EINVAL; 810 811 var->xres_virtual = var->xres; 812 var->yres_virtual = var->yres; 813 814 return 0; 815 } 816 817 static int hvfb_set_par(struct fb_info *info) 818 { 819 struct hv_device *hdev = device_to_hv_device(info->device); 820 821 return synthvid_send_situ(hdev); 822 } 823 824 825 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf) 826 { 827 return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset; 828 } 829 830 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green, 831 unsigned blue, unsigned transp, struct fb_info *info) 832 { 833 u32 *pal = info->pseudo_palette; 834 835 if (regno > 15) 836 return -EINVAL; 837 838 pal[regno] = chan_to_field(red, &info->var.red) 839 | chan_to_field(green, &info->var.green) 840 | chan_to_field(blue, &info->var.blue) 841 | chan_to_field(transp, &info->var.transp); 842 843 return 0; 844 } 845 846 static int hvfb_blank(int blank, struct fb_info *info) 847 { 848 return 1; /* get fb_blank to set the colormap to all black */ 849 } 850 851 static void hvfb_ops_damage_range(struct fb_info *info, off_t off, size_t len) 852 { 853 /* TODO: implement damage handling */ 854 } 855 856 static void hvfb_ops_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height) 857 { 858 struct hvfb_par *par = info->par; 859 860 if (par->synchronous_fb) 861 synthvid_update(info, 0, 0, INT_MAX, INT_MAX); 862 else 863 hvfb_ondemand_refresh_throttle(par, x, y, width, height); 864 } 865 866 /* 867 * TODO: GEN1 codepaths allocate from system or DMA-able memory. Fix the 868 * driver to use the _SYSMEM_ or _DMAMEM_ helpers in these cases. 869 */ 870 FB_GEN_DEFAULT_DEFERRED_IOMEM_OPS(hvfb_ops, 871 hvfb_ops_damage_range, 872 hvfb_ops_damage_area) 873 874 static const struct fb_ops hvfb_ops = { 875 .owner = THIS_MODULE, 876 FB_DEFAULT_DEFERRED_OPS(hvfb_ops), 877 .fb_check_var = hvfb_check_var, 878 .fb_set_par = hvfb_set_par, 879 .fb_setcolreg = hvfb_setcolreg, 880 .fb_blank = hvfb_blank, 881 }; 882 883 /* Get options from kernel paramenter "video=" */ 884 static void hvfb_get_option(struct fb_info *info) 885 { 886 struct hvfb_par *par = info->par; 887 char *opt = NULL, *p; 888 uint x = 0, y = 0; 889 890 if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt) 891 return; 892 893 p = strsep(&opt, "x"); 894 if (!*p || kstrtouint(p, 0, &x) || 895 !opt || !*opt || kstrtouint(opt, 0, &y)) { 896 pr_err("Screen option is invalid: skipped\n"); 897 return; 898 } 899 900 if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN || 901 (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10) && 902 (x * y * screen_depth / 8 > screen_fb_size)) || 903 (par->synthvid_version == SYNTHVID_VERSION_WIN8 && 904 x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8)) { 905 pr_err("Screen resolution option is out of range: skipped\n"); 906 return; 907 } 908 909 screen_width = x; 910 screen_height = y; 911 return; 912 } 913 914 /* 915 * Allocate enough contiguous physical memory. 916 * Return physical address if succeeded or -1 if failed. 917 */ 918 static phys_addr_t hvfb_get_phymem(struct hv_device *hdev, 919 unsigned int request_size) 920 { 921 struct page *page = NULL; 922 dma_addr_t dma_handle; 923 void *vmem; 924 phys_addr_t paddr = 0; 925 unsigned int order = get_order(request_size); 926 927 if (request_size == 0) 928 return -1; 929 930 if (order <= MAX_ORDER) { 931 /* Call alloc_pages if the size is less than 2^MAX_ORDER */ 932 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); 933 if (!page) 934 return -1; 935 936 paddr = (page_to_pfn(page) << PAGE_SHIFT); 937 } else { 938 /* Allocate from CMA */ 939 hdev->device.coherent_dma_mask = DMA_BIT_MASK(64); 940 941 vmem = dma_alloc_coherent(&hdev->device, 942 round_up(request_size, PAGE_SIZE), 943 &dma_handle, 944 GFP_KERNEL | __GFP_NOWARN); 945 946 if (!vmem) 947 return -1; 948 949 paddr = virt_to_phys(vmem); 950 } 951 952 return paddr; 953 } 954 955 /* Release contiguous physical memory */ 956 static void hvfb_release_phymem(struct hv_device *hdev, 957 phys_addr_t paddr, unsigned int size) 958 { 959 unsigned int order = get_order(size); 960 961 if (order <= MAX_ORDER) 962 __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order); 963 else 964 dma_free_coherent(&hdev->device, 965 round_up(size, PAGE_SIZE), 966 phys_to_virt(paddr), 967 paddr); 968 } 969 970 971 /* Get framebuffer memory from Hyper-V video pci space */ 972 static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info) 973 { 974 struct hvfb_par *par = info->par; 975 struct pci_dev *pdev = NULL; 976 void __iomem *fb_virt; 977 int gen2vm = efi_enabled(EFI_BOOT); 978 resource_size_t base, size; 979 phys_addr_t paddr; 980 int ret; 981 982 if (!gen2vm) { 983 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT, 984 PCI_DEVICE_ID_HYPERV_VIDEO, NULL); 985 if (!pdev) { 986 pr_err("Unable to find PCI Hyper-V video\n"); 987 return -ENODEV; 988 } 989 990 base = pci_resource_start(pdev, 0); 991 size = pci_resource_len(pdev, 0); 992 993 /* 994 * For Gen 1 VM, we can directly use the contiguous memory 995 * from VM. If we succeed, deferred IO happens directly 996 * on this allocated framebuffer memory, avoiding extra 997 * memory copy. 998 */ 999 paddr = hvfb_get_phymem(hdev, screen_fb_size); 1000 if (paddr != (phys_addr_t) -1) { 1001 par->mmio_pp = paddr; 1002 par->mmio_vp = par->dio_vp = __va(paddr); 1003 1004 info->fix.smem_start = paddr; 1005 info->fix.smem_len = screen_fb_size; 1006 info->screen_base = par->mmio_vp; 1007 info->screen_size = screen_fb_size; 1008 1009 par->need_docopy = false; 1010 goto getmem_done; 1011 } 1012 pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n"); 1013 } else if (IS_ENABLED(CONFIG_SYSFB)) { 1014 base = screen_info.lfb_base; 1015 size = screen_info.lfb_size; 1016 } else { 1017 goto err1; 1018 } 1019 1020 /* 1021 * Cannot use the contiguous physical memory. 1022 * Allocate mmio space for framebuffer. 1023 */ 1024 dio_fb_size = 1025 screen_width * screen_height * screen_depth / 8; 1026 1027 ret = vmbus_allocate_mmio(&par->mem, hdev, 0, -1, 1028 screen_fb_size, 0x100000, true); 1029 if (ret != 0) { 1030 pr_err("Unable to allocate framebuffer memory\n"); 1031 goto err1; 1032 } 1033 1034 /* 1035 * Map the VRAM cacheable for performance. This is also required for 1036 * VM Connect to display properly for ARM64 Linux VM, as the host also 1037 * maps the VRAM cacheable. 1038 */ 1039 fb_virt = ioremap_cache(par->mem->start, screen_fb_size); 1040 if (!fb_virt) 1041 goto err2; 1042 1043 /* Allocate memory for deferred IO */ 1044 par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE)); 1045 if (par->dio_vp == NULL) 1046 goto err3; 1047 1048 /* Physical address of FB device */ 1049 par->mmio_pp = par->mem->start; 1050 /* Virtual address of FB device */ 1051 par->mmio_vp = (unsigned char *) fb_virt; 1052 1053 info->fix.smem_start = par->mem->start; 1054 info->fix.smem_len = dio_fb_size; 1055 info->screen_base = par->dio_vp; 1056 info->screen_size = dio_fb_size; 1057 1058 getmem_done: 1059 aperture_remove_conflicting_devices(base, size, KBUILD_MODNAME); 1060 1061 if (!gen2vm) { 1062 pci_dev_put(pdev); 1063 } else if (IS_ENABLED(CONFIG_SYSFB)) { 1064 /* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */ 1065 screen_info.lfb_size = 0; 1066 screen_info.lfb_base = 0; 1067 screen_info.orig_video_isVGA = 0; 1068 } 1069 1070 return 0; 1071 1072 err3: 1073 iounmap(fb_virt); 1074 err2: 1075 vmbus_free_mmio(par->mem->start, screen_fb_size); 1076 par->mem = NULL; 1077 err1: 1078 if (!gen2vm) 1079 pci_dev_put(pdev); 1080 1081 return -ENOMEM; 1082 } 1083 1084 /* Release the framebuffer */ 1085 static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info) 1086 { 1087 struct hvfb_par *par = info->par; 1088 1089 if (par->need_docopy) { 1090 vfree(par->dio_vp); 1091 iounmap(info->screen_base); 1092 vmbus_free_mmio(par->mem->start, screen_fb_size); 1093 } else { 1094 hvfb_release_phymem(hdev, info->fix.smem_start, 1095 screen_fb_size); 1096 } 1097 1098 par->mem = NULL; 1099 } 1100 1101 1102 static int hvfb_probe(struct hv_device *hdev, 1103 const struct hv_vmbus_device_id *dev_id) 1104 { 1105 struct fb_info *info; 1106 struct hvfb_par *par; 1107 int ret; 1108 1109 info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device); 1110 if (!info) 1111 return -ENOMEM; 1112 1113 par = info->par; 1114 par->info = info; 1115 par->fb_ready = false; 1116 par->need_docopy = true; 1117 init_completion(&par->wait); 1118 INIT_DELAYED_WORK(&par->dwork, hvfb_update_work); 1119 1120 par->delayed_refresh = false; 1121 spin_lock_init(&par->delayed_refresh_lock); 1122 par->x1 = par->y1 = INT_MAX; 1123 par->x2 = par->y2 = 0; 1124 1125 /* Connect to VSP */ 1126 hv_set_drvdata(hdev, info); 1127 ret = synthvid_connect_vsp(hdev); 1128 if (ret) { 1129 pr_err("Unable to connect to VSP\n"); 1130 goto error1; 1131 } 1132 1133 hvfb_get_option(info); 1134 pr_info("Screen resolution: %dx%d, Color depth: %d, Frame buffer size: %d\n", 1135 screen_width, screen_height, screen_depth, screen_fb_size); 1136 1137 ret = hvfb_getmem(hdev, info); 1138 if (ret) { 1139 pr_err("No memory for framebuffer\n"); 1140 goto error2; 1141 } 1142 1143 /* Set up fb_info */ 1144 info->var.xres_virtual = info->var.xres = screen_width; 1145 info->var.yres_virtual = info->var.yres = screen_height; 1146 info->var.bits_per_pixel = screen_depth; 1147 1148 if (info->var.bits_per_pixel == 16) { 1149 info->var.red = (struct fb_bitfield){11, 5, 0}; 1150 info->var.green = (struct fb_bitfield){5, 6, 0}; 1151 info->var.blue = (struct fb_bitfield){0, 5, 0}; 1152 info->var.transp = (struct fb_bitfield){0, 0, 0}; 1153 } else { 1154 info->var.red = (struct fb_bitfield){16, 8, 0}; 1155 info->var.green = (struct fb_bitfield){8, 8, 0}; 1156 info->var.blue = (struct fb_bitfield){0, 8, 0}; 1157 info->var.transp = (struct fb_bitfield){24, 8, 0}; 1158 } 1159 1160 info->var.activate = FB_ACTIVATE_NOW; 1161 info->var.height = -1; 1162 info->var.width = -1; 1163 info->var.vmode = FB_VMODE_NONINTERLACED; 1164 1165 strcpy(info->fix.id, KBUILD_MODNAME); 1166 info->fix.type = FB_TYPE_PACKED_PIXELS; 1167 info->fix.visual = FB_VISUAL_TRUECOLOR; 1168 info->fix.line_length = screen_width * screen_depth / 8; 1169 info->fix.accel = FB_ACCEL_NONE; 1170 1171 info->fbops = &hvfb_ops; 1172 info->pseudo_palette = par->pseudo_palette; 1173 1174 /* Initialize deferred IO */ 1175 info->fbdefio = &synthvid_defio; 1176 fb_deferred_io_init(info); 1177 1178 /* Send config to host */ 1179 ret = synthvid_send_config(hdev); 1180 if (ret) 1181 goto error; 1182 1183 ret = register_framebuffer(info); 1184 if (ret) { 1185 pr_err("Unable to register framebuffer\n"); 1186 goto error; 1187 } 1188 1189 par->fb_ready = true; 1190 1191 par->synchronous_fb = false; 1192 1193 /* 1194 * We need to be sure this panic notifier runs _before_ the 1195 * vmbus disconnect, so order it by priority. It must execute 1196 * before the function hv_panic_vmbus_unload() [drivers/hv/vmbus_drv.c], 1197 * which is almost at the end of list, with priority = INT_MIN + 1. 1198 */ 1199 par->hvfb_panic_nb.notifier_call = hvfb_on_panic; 1200 par->hvfb_panic_nb.priority = INT_MIN + 10, 1201 atomic_notifier_chain_register(&panic_notifier_list, 1202 &par->hvfb_panic_nb); 1203 1204 return 0; 1205 1206 error: 1207 fb_deferred_io_cleanup(info); 1208 hvfb_putmem(hdev, info); 1209 error2: 1210 vmbus_close(hdev->channel); 1211 error1: 1212 cancel_delayed_work_sync(&par->dwork); 1213 hv_set_drvdata(hdev, NULL); 1214 framebuffer_release(info); 1215 return ret; 1216 } 1217 1218 static void hvfb_remove(struct hv_device *hdev) 1219 { 1220 struct fb_info *info = hv_get_drvdata(hdev); 1221 struct hvfb_par *par = info->par; 1222 1223 atomic_notifier_chain_unregister(&panic_notifier_list, 1224 &par->hvfb_panic_nb); 1225 1226 par->update = false; 1227 par->fb_ready = false; 1228 1229 fb_deferred_io_cleanup(info); 1230 1231 unregister_framebuffer(info); 1232 cancel_delayed_work_sync(&par->dwork); 1233 1234 vmbus_close(hdev->channel); 1235 hv_set_drvdata(hdev, NULL); 1236 1237 hvfb_putmem(hdev, info); 1238 framebuffer_release(info); 1239 } 1240 1241 static int hvfb_suspend(struct hv_device *hdev) 1242 { 1243 struct fb_info *info = hv_get_drvdata(hdev); 1244 struct hvfb_par *par = info->par; 1245 1246 console_lock(); 1247 1248 /* 1 means do suspend */ 1249 fb_set_suspend(info, 1); 1250 1251 cancel_delayed_work_sync(&par->dwork); 1252 cancel_delayed_work_sync(&info->deferred_work); 1253 1254 par->update_saved = par->update; 1255 par->update = false; 1256 par->fb_ready = false; 1257 1258 vmbus_close(hdev->channel); 1259 1260 console_unlock(); 1261 1262 return 0; 1263 } 1264 1265 static int hvfb_resume(struct hv_device *hdev) 1266 { 1267 struct fb_info *info = hv_get_drvdata(hdev); 1268 struct hvfb_par *par = info->par; 1269 int ret; 1270 1271 console_lock(); 1272 1273 ret = synthvid_connect_vsp(hdev); 1274 if (ret != 0) 1275 goto out; 1276 1277 ret = synthvid_send_config(hdev); 1278 if (ret != 0) { 1279 vmbus_close(hdev->channel); 1280 goto out; 1281 } 1282 1283 par->fb_ready = true; 1284 par->update = par->update_saved; 1285 1286 schedule_delayed_work(&info->deferred_work, info->fbdefio->delay); 1287 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY); 1288 1289 /* 0 means do resume */ 1290 fb_set_suspend(info, 0); 1291 1292 out: 1293 console_unlock(); 1294 1295 return ret; 1296 } 1297 1298 1299 static const struct pci_device_id pci_stub_id_table[] = { 1300 { 1301 .vendor = PCI_VENDOR_ID_MICROSOFT, 1302 .device = PCI_DEVICE_ID_HYPERV_VIDEO, 1303 }, 1304 { /* end of list */ } 1305 }; 1306 1307 static const struct hv_vmbus_device_id id_table[] = { 1308 /* Synthetic Video Device GUID */ 1309 {HV_SYNTHVID_GUID}, 1310 {} 1311 }; 1312 1313 MODULE_DEVICE_TABLE(pci, pci_stub_id_table); 1314 MODULE_DEVICE_TABLE(vmbus, id_table); 1315 1316 static struct hv_driver hvfb_drv = { 1317 .name = KBUILD_MODNAME, 1318 .id_table = id_table, 1319 .probe = hvfb_probe, 1320 .remove = hvfb_remove, 1321 .suspend = hvfb_suspend, 1322 .resume = hvfb_resume, 1323 .driver = { 1324 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1325 }, 1326 }; 1327 1328 static int hvfb_pci_stub_probe(struct pci_dev *pdev, 1329 const struct pci_device_id *ent) 1330 { 1331 return 0; 1332 } 1333 1334 static void hvfb_pci_stub_remove(struct pci_dev *pdev) 1335 { 1336 } 1337 1338 static struct pci_driver hvfb_pci_stub_driver = { 1339 .name = KBUILD_MODNAME, 1340 .id_table = pci_stub_id_table, 1341 .probe = hvfb_pci_stub_probe, 1342 .remove = hvfb_pci_stub_remove, 1343 .driver = { 1344 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1345 } 1346 }; 1347 1348 static int __init hvfb_drv_init(void) 1349 { 1350 int ret; 1351 1352 if (fb_modesetting_disabled("hyper_fb")) 1353 return -ENODEV; 1354 1355 ret = vmbus_driver_register(&hvfb_drv); 1356 if (ret != 0) 1357 return ret; 1358 1359 ret = pci_register_driver(&hvfb_pci_stub_driver); 1360 if (ret != 0) { 1361 vmbus_driver_unregister(&hvfb_drv); 1362 return ret; 1363 } 1364 1365 return 0; 1366 } 1367 1368 static void __exit hvfb_drv_exit(void) 1369 { 1370 pci_unregister_driver(&hvfb_pci_stub_driver); 1371 vmbus_driver_unregister(&hvfb_drv); 1372 } 1373 1374 module_init(hvfb_drv_init); 1375 module_exit(hvfb_drv_exit); 1376 1377 MODULE_LICENSE("GPL"); 1378 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver"); 1379