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 78enum pipe_msg_type { 79 PIPE_MSG_INVALID, 80 PIPE_MSG_DATA, 81 PIPE_MSG_MAX 82}; 83 84struct pipe_msg_hdr { 85 u32 type; 86 u32 size; /* size of message after this field */ 87} __packed; 88 89 90enum 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 111struct hvd_screen_info { 112 u16 width; 113 u16 height; 114} __packed; 115 116struct synthvid_msg_hdr { 117 u32 type; 118 u32 size; /* size of this header + payload after this field*/ 119} __packed; 120 121struct synthvid_version_req { 122 u32 version; 123} __packed; 124 125struct synthvid_version_resp { 126 u32 version; 127 u8 is_accepted; 128 u8 max_video_outputs; 129} __packed; 130 131struct synthvid_supported_resolution_req { 132 u8 maximum_resolution_count; 133} __packed; 134 135struct 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 144struct synthvid_vram_location { 145 u64 user_ctx; 146 u8 is_vram_gpa_specified; 147 u64 vram_gpa; 148} __packed; 149 150struct synthvid_vram_location_ack { 151 u64 user_ctx; 152} __packed; 153 154struct 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 163struct synthvid_situation_update { 164 u64 user_ctx; 165 u8 video_output_count; 166 struct video_output_situation video_output[1]; 167} __packed; 168 169struct synthvid_situation_update_ack { 170 u64 user_ctx; 171} __packed; 172 173struct 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 187struct 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 197struct 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 204struct rect { 205 s32 x1, y1; /* top left corner */ 206 s32 x2, y2; /* bottom right corner, exclusive */ 207} __packed; 208 209struct synthvid_dirt { 210 u8 video_output; 211 u8 dirt_count; 212 struct rect rect[1]; 213} __packed; 214 215struct 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 246struct 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 280static uint screen_width = HVFB_WIDTH; 281static uint screen_height = HVFB_HEIGHT; 282static uint screen_depth; 283static uint screen_fb_size; 284static uint dio_fb_size; /* FB size for deferred IO */ 285 286/* Send message to Hyper-V host */ 287static 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 */ 309static 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 */ 337static 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 */ 371static int 372synthvid_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 400static 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 */ 415static 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 448static 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 */ 458static 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 */ 493static 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 */ 520static 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 */ 531static 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 561out: 562 return ret; 563} 564 565/* Get current resolution from the host */ 566static 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 609out: 610 return ret; 611} 612 613/* Connect to VSP (Virtual Service Provider) on host */ 614static 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 661error: 662 vmbus_close(hdev->channel); 663 return ret; 664} 665 666/* Send VRAM and Situation messages to the host */ 667static 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 700out: 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 */ 710static 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 */ 755static 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 780static 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 804static 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 817static 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 825static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf) 826{ 827 return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset; 828} 829 830static 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 846static 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 851static void hvfb_cfb_fillrect(struct fb_info *p, 852 const struct fb_fillrect *rect) 853{ 854 struct hvfb_par *par = p->par; 855 856 cfb_fillrect(p, rect); 857 if (par->synchronous_fb) 858 synthvid_update(p, 0, 0, INT_MAX, INT_MAX); 859 else 860 hvfb_ondemand_refresh_throttle(par, rect->dx, rect->dy, 861 rect->width, rect->height); 862} 863 864static void hvfb_cfb_copyarea(struct fb_info *p, 865 const struct fb_copyarea *area) 866{ 867 struct hvfb_par *par = p->par; 868 869 cfb_copyarea(p, area); 870 if (par->synchronous_fb) 871 synthvid_update(p, 0, 0, INT_MAX, INT_MAX); 872 else 873 hvfb_ondemand_refresh_throttle(par, area->dx, area->dy, 874 area->width, area->height); 875} 876 877static void hvfb_cfb_imageblit(struct fb_info *p, 878 const struct fb_image *image) 879{ 880 struct hvfb_par *par = p->par; 881 882 cfb_imageblit(p, image); 883 if (par->synchronous_fb) 884 synthvid_update(p, 0, 0, INT_MAX, INT_MAX); 885 else 886 hvfb_ondemand_refresh_throttle(par, image->dx, image->dy, 887 image->width, image->height); 888} 889 890static const struct fb_ops hvfb_ops = { 891 .owner = THIS_MODULE, 892 .fb_check_var = hvfb_check_var, 893 .fb_set_par = hvfb_set_par, 894 .fb_setcolreg = hvfb_setcolreg, 895 .fb_fillrect = hvfb_cfb_fillrect, 896 .fb_copyarea = hvfb_cfb_copyarea, 897 .fb_imageblit = hvfb_cfb_imageblit, 898 .fb_blank = hvfb_blank, 899 .fb_mmap = fb_deferred_io_mmap, 900}; 901 902 903/* Get options from kernel paramenter "video=" */ 904static void hvfb_get_option(struct fb_info *info) 905{ 906 struct hvfb_par *par = info->par; 907 char *opt = NULL, *p; 908 uint x = 0, y = 0; 909 910 if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt) 911 return; 912 913 p = strsep(&opt, "x"); 914 if (!*p || kstrtouint(p, 0, &x) || 915 !opt || !*opt || kstrtouint(opt, 0, &y)) { 916 pr_err("Screen option is invalid: skipped\n"); 917 return; 918 } 919 920 if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN || 921 (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10) && 922 (x * y * screen_depth / 8 > screen_fb_size)) || 923 (par->synthvid_version == SYNTHVID_VERSION_WIN8 && 924 x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8)) { 925 pr_err("Screen resolution option is out of range: skipped\n"); 926 return; 927 } 928 929 screen_width = x; 930 screen_height = y; 931 return; 932} 933 934/* 935 * Allocate enough contiguous physical memory. 936 * Return physical address if succeeded or -1 if failed. 937 */ 938static phys_addr_t hvfb_get_phymem(struct hv_device *hdev, 939 unsigned int request_size) 940{ 941 struct page *page = NULL; 942 dma_addr_t dma_handle; 943 void *vmem; 944 phys_addr_t paddr = 0; 945 unsigned int order = get_order(request_size); 946 947 if (request_size == 0) 948 return -1; 949 950 if (order <= MAX_ORDER) { 951 /* Call alloc_pages if the size is less than 2^MAX_ORDER */ 952 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); 953 if (!page) 954 return -1; 955 956 paddr = (page_to_pfn(page) << PAGE_SHIFT); 957 } else { 958 /* Allocate from CMA */ 959 hdev->device.coherent_dma_mask = DMA_BIT_MASK(64); 960 961 vmem = dma_alloc_coherent(&hdev->device, 962 round_up(request_size, PAGE_SIZE), 963 &dma_handle, 964 GFP_KERNEL | __GFP_NOWARN); 965 966 if (!vmem) 967 return -1; 968 969 paddr = virt_to_phys(vmem); 970 } 971 972 return paddr; 973} 974 975/* Release contiguous physical memory */ 976static void hvfb_release_phymem(struct hv_device *hdev, 977 phys_addr_t paddr, unsigned int size) 978{ 979 unsigned int order = get_order(size); 980 981 if (order <= MAX_ORDER) 982 __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order); 983 else 984 dma_free_coherent(&hdev->device, 985 round_up(size, PAGE_SIZE), 986 phys_to_virt(paddr), 987 paddr); 988} 989 990 991/* Get framebuffer memory from Hyper-V video pci space */ 992static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info) 993{ 994 struct hvfb_par *par = info->par; 995 struct pci_dev *pdev = NULL; 996 void __iomem *fb_virt; 997 int gen2vm = efi_enabled(EFI_BOOT); 998 resource_size_t base, size; 999 phys_addr_t paddr; 1000 int ret; 1001 1002 if (!gen2vm) { 1003 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT, 1004 PCI_DEVICE_ID_HYPERV_VIDEO, NULL); 1005 if (!pdev) { 1006 pr_err("Unable to find PCI Hyper-V video\n"); 1007 return -ENODEV; 1008 } 1009 1010 base = pci_resource_start(pdev, 0); 1011 size = pci_resource_len(pdev, 0); 1012 1013 /* 1014 * For Gen 1 VM, we can directly use the contiguous memory 1015 * from VM. If we succeed, deferred IO happens directly 1016 * on this allocated framebuffer memory, avoiding extra 1017 * memory copy. 1018 */ 1019 paddr = hvfb_get_phymem(hdev, screen_fb_size); 1020 if (paddr != (phys_addr_t) -1) { 1021 par->mmio_pp = paddr; 1022 par->mmio_vp = par->dio_vp = __va(paddr); 1023 1024 info->fix.smem_start = paddr; 1025 info->fix.smem_len = screen_fb_size; 1026 info->screen_base = par->mmio_vp; 1027 info->screen_size = screen_fb_size; 1028 1029 par->need_docopy = false; 1030 goto getmem_done; 1031 } 1032 pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n"); 1033 } else { 1034 base = screen_info.lfb_base; 1035 size = screen_info.lfb_size; 1036 } 1037 1038 /* 1039 * Cannot use the contiguous physical memory. 1040 * Allocate mmio space for framebuffer. 1041 */ 1042 dio_fb_size = 1043 screen_width * screen_height * screen_depth / 8; 1044 1045 ret = vmbus_allocate_mmio(&par->mem, hdev, 0, -1, 1046 screen_fb_size, 0x100000, true); 1047 if (ret != 0) { 1048 pr_err("Unable to allocate framebuffer memory\n"); 1049 goto err1; 1050 } 1051 1052 /* 1053 * Map the VRAM cacheable for performance. This is also required for 1054 * VM Connect to display properly for ARM64 Linux VM, as the host also 1055 * maps the VRAM cacheable. 1056 */ 1057 fb_virt = ioremap_cache(par->mem->start, screen_fb_size); 1058 if (!fb_virt) 1059 goto err2; 1060 1061 /* Allocate memory for deferred IO */ 1062 par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE)); 1063 if (par->dio_vp == NULL) 1064 goto err3; 1065 1066 /* Physical address of FB device */ 1067 par->mmio_pp = par->mem->start; 1068 /* Virtual address of FB device */ 1069 par->mmio_vp = (unsigned char *) fb_virt; 1070 1071 info->fix.smem_start = par->mem->start; 1072 info->fix.smem_len = dio_fb_size; 1073 info->screen_base = par->dio_vp; 1074 info->screen_size = dio_fb_size; 1075 1076getmem_done: 1077 aperture_remove_conflicting_devices(base, size, KBUILD_MODNAME); 1078 1079 if (gen2vm) { 1080 /* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */ 1081 screen_info.lfb_size = 0; 1082 screen_info.lfb_base = 0; 1083 screen_info.orig_video_isVGA = 0; 1084 } else { 1085 pci_dev_put(pdev); 1086 } 1087 1088 return 0; 1089 1090err3: 1091 iounmap(fb_virt); 1092err2: 1093 vmbus_free_mmio(par->mem->start, screen_fb_size); 1094 par->mem = NULL; 1095err1: 1096 if (!gen2vm) 1097 pci_dev_put(pdev); 1098 1099 return -ENOMEM; 1100} 1101 1102/* Release the framebuffer */ 1103static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info) 1104{ 1105 struct hvfb_par *par = info->par; 1106 1107 if (par->need_docopy) { 1108 vfree(par->dio_vp); 1109 iounmap(info->screen_base); 1110 vmbus_free_mmio(par->mem->start, screen_fb_size); 1111 } else { 1112 hvfb_release_phymem(hdev, info->fix.smem_start, 1113 screen_fb_size); 1114 } 1115 1116 par->mem = NULL; 1117} 1118 1119 1120static int hvfb_probe(struct hv_device *hdev, 1121 const struct hv_vmbus_device_id *dev_id) 1122{ 1123 struct fb_info *info; 1124 struct hvfb_par *par; 1125 int ret; 1126 1127 info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device); 1128 if (!info) 1129 return -ENOMEM; 1130 1131 par = info->par; 1132 par->info = info; 1133 par->fb_ready = false; 1134 par->need_docopy = true; 1135 init_completion(&par->wait); 1136 INIT_DELAYED_WORK(&par->dwork, hvfb_update_work); 1137 1138 par->delayed_refresh = false; 1139 spin_lock_init(&par->delayed_refresh_lock); 1140 par->x1 = par->y1 = INT_MAX; 1141 par->x2 = par->y2 = 0; 1142 1143 /* Connect to VSP */ 1144 hv_set_drvdata(hdev, info); 1145 ret = synthvid_connect_vsp(hdev); 1146 if (ret) { 1147 pr_err("Unable to connect to VSP\n"); 1148 goto error1; 1149 } 1150 1151 hvfb_get_option(info); 1152 pr_info("Screen resolution: %dx%d, Color depth: %d, Frame buffer size: %d\n", 1153 screen_width, screen_height, screen_depth, screen_fb_size); 1154 1155 ret = hvfb_getmem(hdev, info); 1156 if (ret) { 1157 pr_err("No memory for framebuffer\n"); 1158 goto error2; 1159 } 1160 1161 /* Set up fb_info */ 1162 info->var.xres_virtual = info->var.xres = screen_width; 1163 info->var.yres_virtual = info->var.yres = screen_height; 1164 info->var.bits_per_pixel = screen_depth; 1165 1166 if (info->var.bits_per_pixel == 16) { 1167 info->var.red = (struct fb_bitfield){11, 5, 0}; 1168 info->var.green = (struct fb_bitfield){5, 6, 0}; 1169 info->var.blue = (struct fb_bitfield){0, 5, 0}; 1170 info->var.transp = (struct fb_bitfield){0, 0, 0}; 1171 } else { 1172 info->var.red = (struct fb_bitfield){16, 8, 0}; 1173 info->var.green = (struct fb_bitfield){8, 8, 0}; 1174 info->var.blue = (struct fb_bitfield){0, 8, 0}; 1175 info->var.transp = (struct fb_bitfield){24, 8, 0}; 1176 } 1177 1178 info->var.activate = FB_ACTIVATE_NOW; 1179 info->var.height = -1; 1180 info->var.width = -1; 1181 info->var.vmode = FB_VMODE_NONINTERLACED; 1182 1183 strcpy(info->fix.id, KBUILD_MODNAME); 1184 info->fix.type = FB_TYPE_PACKED_PIXELS; 1185 info->fix.visual = FB_VISUAL_TRUECOLOR; 1186 info->fix.line_length = screen_width * screen_depth / 8; 1187 info->fix.accel = FB_ACCEL_NONE; 1188 1189 info->fbops = &hvfb_ops; 1190 info->pseudo_palette = par->pseudo_palette; 1191 1192 /* Initialize deferred IO */ 1193 info->fbdefio = &synthvid_defio; 1194 fb_deferred_io_init(info); 1195 1196 /* Send config to host */ 1197 ret = synthvid_send_config(hdev); 1198 if (ret) 1199 goto error; 1200 1201 ret = register_framebuffer(info); 1202 if (ret) { 1203 pr_err("Unable to register framebuffer\n"); 1204 goto error; 1205 } 1206 1207 par->fb_ready = true; 1208 1209 par->synchronous_fb = false; 1210 1211 /* 1212 * We need to be sure this panic notifier runs _before_ the 1213 * vmbus disconnect, so order it by priority. It must execute 1214 * before the function hv_panic_vmbus_unload() [drivers/hv/vmbus_drv.c], 1215 * which is almost at the end of list, with priority = INT_MIN + 1. 1216 */ 1217 par->hvfb_panic_nb.notifier_call = hvfb_on_panic; 1218 par->hvfb_panic_nb.priority = INT_MIN + 10, 1219 atomic_notifier_chain_register(&panic_notifier_list, 1220 &par->hvfb_panic_nb); 1221 1222 return 0; 1223 1224error: 1225 fb_deferred_io_cleanup(info); 1226 hvfb_putmem(hdev, info); 1227error2: 1228 vmbus_close(hdev->channel); 1229error1: 1230 cancel_delayed_work_sync(&par->dwork); 1231 hv_set_drvdata(hdev, NULL); 1232 framebuffer_release(info); 1233 return ret; 1234} 1235 1236static void hvfb_remove(struct hv_device *hdev) 1237{ 1238 struct fb_info *info = hv_get_drvdata(hdev); 1239 struct hvfb_par *par = info->par; 1240 1241 atomic_notifier_chain_unregister(&panic_notifier_list, 1242 &par->hvfb_panic_nb); 1243 1244 par->update = false; 1245 par->fb_ready = false; 1246 1247 fb_deferred_io_cleanup(info); 1248 1249 unregister_framebuffer(info); 1250 cancel_delayed_work_sync(&par->dwork); 1251 1252 vmbus_close(hdev->channel); 1253 hv_set_drvdata(hdev, NULL); 1254 1255 hvfb_putmem(hdev, info); 1256 framebuffer_release(info); 1257} 1258 1259static int hvfb_suspend(struct hv_device *hdev) 1260{ 1261 struct fb_info *info = hv_get_drvdata(hdev); 1262 struct hvfb_par *par = info->par; 1263 1264 console_lock(); 1265 1266 /* 1 means do suspend */ 1267 fb_set_suspend(info, 1); 1268 1269 cancel_delayed_work_sync(&par->dwork); 1270 cancel_delayed_work_sync(&info->deferred_work); 1271 1272 par->update_saved = par->update; 1273 par->update = false; 1274 par->fb_ready = false; 1275 1276 vmbus_close(hdev->channel); 1277 1278 console_unlock(); 1279 1280 return 0; 1281} 1282 1283static int hvfb_resume(struct hv_device *hdev) 1284{ 1285 struct fb_info *info = hv_get_drvdata(hdev); 1286 struct hvfb_par *par = info->par; 1287 int ret; 1288 1289 console_lock(); 1290 1291 ret = synthvid_connect_vsp(hdev); 1292 if (ret != 0) 1293 goto out; 1294 1295 ret = synthvid_send_config(hdev); 1296 if (ret != 0) { 1297 vmbus_close(hdev->channel); 1298 goto out; 1299 } 1300 1301 par->fb_ready = true; 1302 par->update = par->update_saved; 1303 1304 schedule_delayed_work(&info->deferred_work, info->fbdefio->delay); 1305 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY); 1306 1307 /* 0 means do resume */ 1308 fb_set_suspend(info, 0); 1309 1310out: 1311 console_unlock(); 1312 1313 return ret; 1314} 1315 1316 1317static const struct pci_device_id pci_stub_id_table[] = { 1318 { 1319 .vendor = PCI_VENDOR_ID_MICROSOFT, 1320 .device = PCI_DEVICE_ID_HYPERV_VIDEO, 1321 }, 1322 { /* end of list */ } 1323}; 1324 1325static const struct hv_vmbus_device_id id_table[] = { 1326 /* Synthetic Video Device GUID */ 1327 {HV_SYNTHVID_GUID}, 1328 {} 1329}; 1330 1331MODULE_DEVICE_TABLE(pci, pci_stub_id_table); 1332MODULE_DEVICE_TABLE(vmbus, id_table); 1333 1334static struct hv_driver hvfb_drv = { 1335 .name = KBUILD_MODNAME, 1336 .id_table = id_table, 1337 .probe = hvfb_probe, 1338 .remove = hvfb_remove, 1339 .suspend = hvfb_suspend, 1340 .resume = hvfb_resume, 1341 .driver = { 1342 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1343 }, 1344}; 1345 1346static int hvfb_pci_stub_probe(struct pci_dev *pdev, 1347 const struct pci_device_id *ent) 1348{ 1349 return 0; 1350} 1351 1352static void hvfb_pci_stub_remove(struct pci_dev *pdev) 1353{ 1354} 1355 1356static struct pci_driver hvfb_pci_stub_driver = { 1357 .name = KBUILD_MODNAME, 1358 .id_table = pci_stub_id_table, 1359 .probe = hvfb_pci_stub_probe, 1360 .remove = hvfb_pci_stub_remove, 1361 .driver = { 1362 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1363 } 1364}; 1365 1366static int __init hvfb_drv_init(void) 1367{ 1368 int ret; 1369 1370 if (fb_modesetting_disabled("hyper_fb")) 1371 return -ENODEV; 1372 1373 ret = vmbus_driver_register(&hvfb_drv); 1374 if (ret != 0) 1375 return ret; 1376 1377 ret = pci_register_driver(&hvfb_pci_stub_driver); 1378 if (ret != 0) { 1379 vmbus_driver_unregister(&hvfb_drv); 1380 return ret; 1381 } 1382 1383 return 0; 1384} 1385 1386static void __exit hvfb_drv_exit(void) 1387{ 1388 pci_unregister_driver(&hvfb_pci_stub_driver); 1389 vmbus_driver_unregister(&hvfb_drv); 1390} 1391 1392module_init(hvfb_drv_init); 1393module_exit(hvfb_drv_exit); 1394 1395MODULE_LICENSE("GPL"); 1396MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver"); 1397