drivers/misc/vmw_vmci/vmci_guest.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * VMware VMCI Driver
   4  *
   5  * Copyright (C) 2012 VMware, Inc. All rights reserved.
   6  */
   7
   8 #include <linux/vmw_vmci_defs.h>
   9 #include <linux/vmw_vmci_api.h>
  10 #include <linux/moduleparam.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/highmem.h>
  13 #include <linux/kernel.h>
  14 #include <linux/mm.h>
  15 #include <linux/module.h>
  16 #include <linux/processor.h>
  17 #include <linux/sched.h>
  18 #include <linux/slab.h>
  19 #include <linux/init.h>
  20 #include <linux/pci.h>
  21 #include <linux/smp.h>
  22 #include <linux/io.h>
  23 #include <linux/vmalloc.h>
  24
  25 #include "vmci_datagram.h"
  26 #include "vmci_doorbell.h"
  27 #include "vmci_context.h"
  28 #include "vmci_driver.h"
  29 #include "vmci_event.h"
  30
  31 #define PCI_DEVICE_ID_VMWARE_VMCI       0x0740
  32
  33 #define VMCI_UTIL_NUM_RESOURCES 1
  34
  35 /*
  36  * Datagram buffers for DMA send/receive must accommodate at least
  37  * a maximum sized datagram and the header.
  38  */
  39 #define VMCI_DMA_DG_BUFFER_SIZE (VMCI_MAX_DG_SIZE + PAGE_SIZE)
  40
  41 static bool vmci_disable_msi;
  42 module_param_named(disable_msi, vmci_disable_msi, bool, 0);
  43 MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
  44
  45 static bool vmci_disable_msix;
  46 module_param_named(disable_msix, vmci_disable_msix, bool, 0);
  47 MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
  48
  49 static u32 ctx_update_sub_id = VMCI_INVALID_ID;
  50 static u32 vm_context_id = VMCI_INVALID_ID;
  51
  52 struct vmci_guest_device {
  53         struct device *dev;     /* PCI device we are attached to */
  54         void __iomem *iobase;
  55         void __iomem *mmio_base;
  56
  57         bool exclusive_vectors;
  58
  59         struct wait_queue_head inout_wq;
  60
  61         void *data_buffer;
  62         dma_addr_t data_buffer_base;
  63         void *tx_buffer;
  64         dma_addr_t tx_buffer_base;
  65         void *notification_bitmap;
  66         dma_addr_t notification_base;
  67 };
  68
  69 static bool use_ppn64;
  70
  71 bool vmci_use_ppn64(void)
  72 {
  73         return use_ppn64;
  74 }
  75
  76 /* vmci_dev singleton device and supporting data*/
  77 struct pci_dev *vmci_pdev;
  78 static struct vmci_guest_device *vmci_dev_g;
  79 static DEFINE_SPINLOCK(vmci_dev_spinlock);
  80
  81 static atomic_t vmci_num_guest_devices = ATOMIC_INIT(0);
  82
  83 bool vmci_guest_code_active(void)
  84 {
  85         return atomic_read(&vmci_num_guest_devices) != 0;
  86 }
  87
  88 u32 vmci_get_vm_context_id(void)
  89 {
  90         if (vm_context_id == VMCI_INVALID_ID) {
  91                 struct vmci_datagram get_cid_msg;
  92                 get_cid_msg.dst =
  93                     vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
  94                                      VMCI_GET_CONTEXT_ID);
  95                 get_cid_msg.src = VMCI_ANON_SRC_HANDLE;
  96                 get_cid_msg.payload_size = 0;
  97                 vm_context_id = vmci_send_datagram(&get_cid_msg);
  98         }
  99         return vm_context_id;
 100 }
 101
 102 static unsigned int vmci_read_reg(struct vmci_guest_device *dev, u32 reg)
 103 {
 104         if (dev->mmio_base != NULL)
 105                 return readl(dev->mmio_base + reg);
 106         return ioread32(dev->iobase + reg);
 107 }
 108
 109 static void vmci_write_reg(struct vmci_guest_device *dev, u32 val, u32 reg)
 110 {
 111         if (dev->mmio_base != NULL)
 112                 writel(val, dev->mmio_base + reg);
 113         else
 114                 iowrite32(val, dev->iobase + reg);
 115 }
 116
 117 static void vmci_read_data(struct vmci_guest_device *vmci_dev,
 118                            void *dest, size_t size)
 119 {
 120         if (vmci_dev->mmio_base == NULL)
 121                 ioread8_rep(vmci_dev->iobase + VMCI_DATA_IN_ADDR,
 122                             dest, size);
 123         else {
 124                 /*
 125                  * For DMA datagrams, the data_buffer will contain the header on the
 126                  * first page, followed by the incoming datagram(s) on the following
 127                  * pages. The header uses an S/G element immediately following the
 128                  * header on the first page to point to the data area.
 129                  */
 130                 struct vmci_data_in_out_header *buffer_header = vmci_dev->data_buffer;
 131                 struct vmci_sg_elem *sg_array = (struct vmci_sg_elem *)(buffer_header + 1);
 132                 size_t buffer_offset = dest - vmci_dev->data_buffer;
 133
 134                 buffer_header->opcode = 1;
 135                 buffer_header->size = 1;
 136                 buffer_header->busy = 0;
 137                 sg_array[0].addr = vmci_dev->data_buffer_base + buffer_offset;
 138                 sg_array[0].size = size;
 139
 140                 vmci_write_reg(vmci_dev, lower_32_bits(vmci_dev->data_buffer_base),
 141                                VMCI_DATA_IN_LOW_ADDR);
 142
 143                 wait_event(vmci_dev->inout_wq, buffer_header->busy == 1);
 144         }
 145 }
 146
 147 static int vmci_write_data(struct vmci_guest_device *dev,
 148                            struct vmci_datagram *dg)
 149 {
 150         int result;
 151
 152         if (dev->mmio_base != NULL) {
 153                 struct vmci_data_in_out_header *buffer_header = dev->tx_buffer;
 154                 u8 *dg_out_buffer = (u8 *)(buffer_header + 1);
 155
 156                 if (VMCI_DG_SIZE(dg) > VMCI_MAX_DG_SIZE)
 157                         return VMCI_ERROR_INVALID_ARGS;
 158
 159                 /*
 160                  * Initialize send buffer with outgoing datagram
 161                  * and set up header for inline data. Device will
 162                  * not access buffer asynchronously - only after
 163                  * the write to VMCI_DATA_OUT_LOW_ADDR.
 164                  */
 165                 memcpy(dg_out_buffer, dg, VMCI_DG_SIZE(dg));
 166                 buffer_header->opcode = 0;
 167                 buffer_header->size = VMCI_DG_SIZE(dg);
 168                 buffer_header->busy = 1;
 169
 170                 vmci_write_reg(dev, lower_32_bits(dev->tx_buffer_base),
 171                                VMCI_DATA_OUT_LOW_ADDR);
 172
 173                 /* Caller holds a spinlock, so cannot block. */
 174                 spin_until_cond(buffer_header->busy == 0);
 175
 176                 result = vmci_read_reg(vmci_dev_g, VMCI_RESULT_LOW_ADDR);
 177                 if (result == VMCI_SUCCESS)
 178                         result = (int)buffer_header->result;
 179         } else {
 180                 iowrite8_rep(dev->iobase + VMCI_DATA_OUT_ADDR,
 181                              dg, VMCI_DG_SIZE(dg));
 182                 result = vmci_read_reg(vmci_dev_g, VMCI_RESULT_LOW_ADDR);
 183         }
 184
 185         return result;
 186 }
 187
 188 /*
 189  * VM to hypervisor call mechanism. We use the standard VMware naming
 190  * convention since shared code is calling this function as well.
 191  */
 192 int vmci_send_datagram(struct vmci_datagram *dg)
 193 {
 194         unsigned long flags;
 195         int result;
 196
 197         /* Check args. */
 198         if (dg == NULL)
 199                 return VMCI_ERROR_INVALID_ARGS;
 200
 201         /*
 202          * Need to acquire spinlock on the device because the datagram
 203          * data may be spread over multiple pages and the monitor may
 204          * interleave device user rpc calls from multiple
 205          * VCPUs. Acquiring the spinlock precludes that
 206          * possibility. Disabling interrupts to avoid incoming
 207          * datagrams during a "rep out" and possibly landing up in
 208          * this function.
 209          */
 210         spin_lock_irqsave(&vmci_dev_spinlock, flags);
 211
 212         if (vmci_dev_g) {
 213                 vmci_write_data(vmci_dev_g, dg);
 214                 result = vmci_read_reg(vmci_dev_g, VMCI_RESULT_LOW_ADDR);
 215         } else {
 216                 result = VMCI_ERROR_UNAVAILABLE;
 217         }
 218
 219         spin_unlock_irqrestore(&vmci_dev_spinlock, flags);
 220
 221         return result;
 222 }
 223 EXPORT_SYMBOL_GPL(vmci_send_datagram);
 224
 225 /*
 226  * Gets called with the new context id if updated or resumed.
 227  * Context id.
 228  */
 229 static void vmci_guest_cid_update(u32 sub_id,
 230                                   const struct vmci_event_data *event_data,
 231                                   void *client_data)
 232 {
 233         const struct vmci_event_payld_ctx *ev_payload =
 234                                 vmci_event_data_const_payload(event_data);
 235
 236         if (sub_id != ctx_update_sub_id) {
 237                 pr_devel("Invalid subscriber (ID=0x%x)\n", sub_id);
 238                 return;
 239         }
 240
 241         if (!event_data || ev_payload->context_id == VMCI_INVALID_ID) {
 242                 pr_devel("Invalid event data\n");
 243                 return;
 244         }
 245
 246         pr_devel("Updating context from (ID=0x%x) to (ID=0x%x) on event (type=%d)\n",
 247                  vm_context_id, ev_payload->context_id, event_data->event);
 248
 249         vm_context_id = ev_payload->context_id;
 250 }
 251
 252 /*
 253  * Verify that the host supports the hypercalls we need. If it does not,
 254  * try to find fallback hypercalls and use those instead.  Returns 0 if
 255  * required hypercalls (or fallback hypercalls) are supported by the host,
 256  * an error code otherwise.
 257  */
 258 static int vmci_check_host_caps(struct pci_dev *pdev)
 259 {
 260         bool result;
 261         struct vmci_resource_query_msg *msg;
 262         u32 msg_size = sizeof(struct vmci_resource_query_hdr) +
 263                                 VMCI_UTIL_NUM_RESOURCES * sizeof(u32);
 264         struct vmci_datagram *check_msg;
 265
 266         check_msg = kzalloc(msg_size, GFP_KERNEL);
 267         if (!check_msg) {
 268                 dev_err(&pdev->dev, "%s: Insufficient memory\n", __func__);
 269                 return -ENOMEM;
 270         }
 271
 272         check_msg->dst = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
 273                                           VMCI_RESOURCES_QUERY);
 274         check_msg->src = VMCI_ANON_SRC_HANDLE;
 275         check_msg->payload_size = msg_size - VMCI_DG_HEADERSIZE;
 276         msg = (struct vmci_resource_query_msg *)VMCI_DG_PAYLOAD(check_msg);
 277
 278         msg->num_resources = VMCI_UTIL_NUM_RESOURCES;
 279         msg->resources[0] = VMCI_GET_CONTEXT_ID;
 280
 281         /* Checks that hyper calls are supported */
 282         result = vmci_send_datagram(check_msg) == 0x01;
 283         kfree(check_msg);
 284
 285         dev_dbg(&pdev->dev, "%s: Host capability check: %s\n",
 286                 __func__, result ? "PASSED" : "FAILED");
 287
 288         /* We need the vector. There are no fallbacks. */
 289         return result ? 0 : -ENXIO;
 290 }
 291
 292 /*
 293  * Reads datagrams from the device and dispatches them. For IO port
 294  * based access to the device, we always start reading datagrams into
 295  * only the first page of the datagram buffer. If the datagrams don't
 296  * fit into one page, we use the maximum datagram buffer size for the
 297  * remainder of the invocation. This is a simple heuristic for not
 298  * penalizing small datagrams. For DMA-based datagrams, we always
 299  * use the maximum datagram buffer size, since there is no performance
 300  * penalty for doing so.
 301  *
 302  * This function assumes that it has exclusive access to the data
 303  * in register(s) for the duration of the call.
 304  */
 305 static void vmci_dispatch_dgs(struct vmci_guest_device *vmci_dev)
 306 {
 307         u8 *dg_in_buffer = vmci_dev->data_buffer;
 308         struct vmci_datagram *dg;
 309         size_t dg_in_buffer_size = VMCI_MAX_DG_SIZE;
 310         size_t current_dg_in_buffer_size;
 311         size_t remaining_bytes;
 312         bool is_io_port = vmci_dev->mmio_base == NULL;
 313
 314         BUILD_BUG_ON(VMCI_MAX_DG_SIZE < PAGE_SIZE);
 315
 316         if (!is_io_port) {
 317                 /* For mmio, the first page is used for the header. */
 318                 dg_in_buffer += PAGE_SIZE;
 319
 320                 /*
 321                  * For DMA-based datagram operations, there is no performance
 322                  * penalty for reading the maximum buffer size.
 323                  */
 324                 current_dg_in_buffer_size = VMCI_MAX_DG_SIZE;
 325         } else {
 326                 current_dg_in_buffer_size = PAGE_SIZE;
 327         }
 328         vmci_read_data(vmci_dev, dg_in_buffer, current_dg_in_buffer_size);
 329         dg = (struct vmci_datagram *)dg_in_buffer;
 330         remaining_bytes = current_dg_in_buffer_size;
 331
 332         /*
 333          * Read through the buffer until an invalid datagram header is
 334          * encountered. The exit condition for datagrams read through
 335          * VMCI_DATA_IN_ADDR is a bit more complicated, since a datagram
 336          * can start on any page boundary in the buffer.
 337          */
 338         while (dg->dst.resource != VMCI_INVALID_ID ||
 339                (is_io_port && remaining_bytes > PAGE_SIZE)) {
 340                 unsigned dg_in_size;
 341
 342                 /*
 343                  * If using VMCI_DATA_IN_ADDR, skip to the next page
 344                  * as a datagram can start on any page boundary.
 345                  */
 346                 if (dg->dst.resource == VMCI_INVALID_ID) {
 347                         dg = (struct vmci_datagram *)roundup(
 348                                 (uintptr_t)dg + 1, PAGE_SIZE);
 349                         remaining_bytes =
 350                                 (size_t)(dg_in_buffer +
 351                                          current_dg_in_buffer_size -
 352                                          (u8 *)dg);
 353                         continue;
 354                 }
 355
 356                 dg_in_size = VMCI_DG_SIZE_ALIGNED(dg);
 357
 358                 if (dg_in_size <= dg_in_buffer_size) {
 359                         int result;
 360
 361                         /*
 362                          * If the remaining bytes in the datagram
 363                          * buffer doesn't contain the complete
 364                          * datagram, we first make sure we have enough
 365                          * room for it and then we read the reminder
 366                          * of the datagram and possibly any following
 367                          * datagrams.
 368                          */
 369                         if (dg_in_size > remaining_bytes) {
 370                                 if (remaining_bytes !=
 371                                     current_dg_in_buffer_size) {
 372
 373                                         /*
 374                                          * We move the partial
 375                                          * datagram to the front and
 376                                          * read the reminder of the
 377                                          * datagram and possibly
 378                                          * following calls into the
 379                                          * following bytes.
 380                                          */
 381                                         memmove(dg_in_buffer, dg_in_buffer +
 382                                                 current_dg_in_buffer_size -
 383                                                 remaining_bytes,
 384                                                 remaining_bytes);
 385                                         dg = (struct vmci_datagram *)
 386                                             dg_in_buffer;
 387                                 }
 388
 389                                 if (current_dg_in_buffer_size !=
 390                                     dg_in_buffer_size)
 391                                         current_dg_in_buffer_size =
 392                                             dg_in_buffer_size;
 393
 394                                 vmci_read_data(vmci_dev,
 395                                                dg_in_buffer +
 396                                                 remaining_bytes,
 397                                                current_dg_in_buffer_size -
 398                                                 remaining_bytes);
 399                         }
 400
 401                         /*
 402                          * We special case event datagrams from the
 403                          * hypervisor.
 404                          */
 405                         if (dg->src.context == VMCI_HYPERVISOR_CONTEXT_ID &&
 406                             dg->dst.resource == VMCI_EVENT_HANDLER) {
 407                                 result = vmci_event_dispatch(dg);
 408                         } else {
 409                                 result = vmci_datagram_invoke_guest_handler(dg);
 410                         }
 411                         if (result < VMCI_SUCCESS)
 412                                 dev_dbg(vmci_dev->dev,
 413                                         "Datagram with resource (ID=0x%x) failed (err=%d)\n",
 414                                          dg->dst.resource, result);
 415
 416                         /* On to the next datagram. */
 417                         dg = (struct vmci_datagram *)((u8 *)dg +
 418                                                       dg_in_size);
 419                 } else {
 420                         size_t bytes_to_skip;
 421
 422                         /*
 423                          * Datagram doesn't fit in datagram buffer of maximal
 424                          * size. We drop it.
 425                          */
 426                         dev_dbg(vmci_dev->dev,
 427                                 "Failed to receive datagram (size=%u bytes)\n",
 428                                  dg_in_size);
 429
 430                         bytes_to_skip = dg_in_size - remaining_bytes;
 431                         if (current_dg_in_buffer_size != dg_in_buffer_size)
 432                                 current_dg_in_buffer_size = dg_in_buffer_size;
 433
 434                         for (;;) {
 435                                 vmci_read_data(vmci_dev, dg_in_buffer,
 436                                                current_dg_in_buffer_size);
 437                                 if (bytes_to_skip <= current_dg_in_buffer_size)
 438                                         break;
 439
 440                                 bytes_to_skip -= current_dg_in_buffer_size;
 441                         }
 442                         dg = (struct vmci_datagram *)(dg_in_buffer +
 443                                                       bytes_to_skip);
 444                 }
 445
 446                 remaining_bytes =
 447                     (size_t) (dg_in_buffer + current_dg_in_buffer_size -
 448                               (u8 *)dg);
 449
 450                 if (remaining_bytes < VMCI_DG_HEADERSIZE) {
 451                         /* Get the next batch of datagrams. */
 452
 453                         vmci_read_data(vmci_dev, dg_in_buffer,
 454                                     current_dg_in_buffer_size);
 455                         dg = (struct vmci_datagram *)dg_in_buffer;
 456                         remaining_bytes = current_dg_in_buffer_size;
 457                 }
 458         }
 459 }
 460
 461 /*
 462  * Scans the notification bitmap for raised flags, clears them
 463  * and handles the notifications.
 464  */
 465 static void vmci_process_bitmap(struct vmci_guest_device *dev)
 466 {
 467         if (!dev->notification_bitmap) {
 468                 dev_dbg(dev->dev, "No bitmap present in %s\n", __func__);
 469                 return;
 470         }
 471
 472         vmci_dbell_scan_notification_entries(dev->notification_bitmap);
 473 }
 474
 475 /*
 476  * Interrupt handler for legacy or MSI interrupt, or for first MSI-X
 477  * interrupt (vector VMCI_INTR_DATAGRAM).
 478  */
 479 static irqreturn_t vmci_interrupt(int irq, void *_dev)
 480 {
 481         struct vmci_guest_device *dev = _dev;
 482
 483         /*
 484          * If we are using MSI-X with exclusive vectors then we simply call
 485          * vmci_dispatch_dgs(), since we know the interrupt was meant for us.
 486          * Otherwise we must read the ICR to determine what to do.
 487          */
 488
 489         if (dev->exclusive_vectors) {
 490                 vmci_dispatch_dgs(dev);
 491         } else {
 492                 unsigned int icr;
 493
 494                 /* Acknowledge interrupt and determine what needs doing. */
 495                 icr = vmci_read_reg(dev, VMCI_ICR_ADDR);
 496                 if (icr == 0 || icr == ~0)
 497                         return IRQ_NONE;
 498
 499                 if (icr & VMCI_ICR_DATAGRAM) {
 500                         vmci_dispatch_dgs(dev);
 501                         icr &= ~VMCI_ICR_DATAGRAM;
 502                 }
 503
 504                 if (icr & VMCI_ICR_NOTIFICATION) {
 505                         vmci_process_bitmap(dev);
 506                         icr &= ~VMCI_ICR_NOTIFICATION;
 507                 }
 508
 509
 510                 if (icr & VMCI_ICR_DMA_DATAGRAM) {
 511                         wake_up_all(&dev->inout_wq);
 512                         icr &= ~VMCI_ICR_DMA_DATAGRAM;
 513                 }
 514
 515                 if (icr != 0)
 516                         dev_warn(dev->dev,
 517                                  "Ignoring unknown interrupt cause (%d)\n",
 518                                  icr);
 519         }
 520
 521         return IRQ_HANDLED;
 522 }
 523
 524 /*
 525  * Interrupt handler for MSI-X interrupt vector VMCI_INTR_NOTIFICATION,
 526  * which is for the notification bitmap.  Will only get called if we are
 527  * using MSI-X with exclusive vectors.
 528  */
 529 static irqreturn_t vmci_interrupt_bm(int irq, void *_dev)
 530 {
 531         struct vmci_guest_device *dev = _dev;
 532
 533         /* For MSI-X we can just assume it was meant for us. */
 534         vmci_process_bitmap(dev);
 535
 536         return IRQ_HANDLED;
 537 }
 538
 539 /*
 540  * Interrupt handler for MSI-X interrupt vector VMCI_INTR_DMA_DATAGRAM,
 541  * which is for the completion of a DMA datagram send or receive operation.
 542  * Will only get called if we are using MSI-X with exclusive vectors.
 543  */
 544 static irqreturn_t vmci_interrupt_dma_datagram(int irq, void *_dev)
 545 {
 546         struct vmci_guest_device *dev = _dev;
 547
 548         wake_up_all(&dev->inout_wq);
 549
 550         return IRQ_HANDLED;
 551 }
 552
 553 static void vmci_free_dg_buffers(struct vmci_guest_device *vmci_dev)
 554 {
 555         if (vmci_dev->mmio_base != NULL) {
 556                 if (vmci_dev->tx_buffer != NULL)
 557                         dma_free_coherent(vmci_dev->dev,
 558                                           VMCI_DMA_DG_BUFFER_SIZE,
 559                                           vmci_dev->tx_buffer,
 560                                           vmci_dev->tx_buffer_base);
 561                 if (vmci_dev->data_buffer != NULL)
 562                         dma_free_coherent(vmci_dev->dev,
 563                                           VMCI_DMA_DG_BUFFER_SIZE,
 564                                           vmci_dev->data_buffer,
 565                                           vmci_dev->data_buffer_base);
 566         } else {
 567                 vfree(vmci_dev->data_buffer);
 568         }
 569 }
 570
 571 /*
 572  * Most of the initialization at module load time is done here.
 573  */
 574 static int vmci_guest_probe_device(struct pci_dev *pdev,
 575                                    const struct pci_device_id *id)
 576 {
 577         struct vmci_guest_device *vmci_dev;
 578         void __iomem *iobase = NULL;
 579         void __iomem *mmio_base = NULL;
 580         unsigned int num_irq_vectors;
 581         unsigned int capabilities;
 582         unsigned int caps_in_use;
 583         unsigned long cmd;
 584         int vmci_err;
 585         int error;
 586
 587         dev_dbg(&pdev->dev, "Probing for vmci/PCI guest device\n");
 588
 589         error = pcim_enable_device(pdev);
 590         if (error) {
 591                 dev_err(&pdev->dev,
 592                         "Failed to enable VMCI device: %d\n", error);
 593                 return error;
 594         }
 595
 596         /*
 597          * The VMCI device with mmio access to registers requests 256KB
 598          * for BAR1. If present, driver will use new VMCI device
 599          * functionality for register access and datagram send/recv.
 600          */
 601
 602         if (pci_resource_len(pdev, 1) == VMCI_WITH_MMIO_ACCESS_BAR_SIZE) {
 603                 dev_info(&pdev->dev, "MMIO register access is available\n");
 604                 mmio_base = pci_iomap_range(pdev, 1, VMCI_MMIO_ACCESS_OFFSET,
 605                                             VMCI_MMIO_ACCESS_SIZE);
 606                 /* If the map fails, we fall back to IOIO access. */
 607                 if (!mmio_base)
 608                         dev_warn(&pdev->dev, "Failed to map MMIO register access\n");
 609         }
 610
 611         if (!mmio_base) {
 612                 if (IS_ENABLED(CONFIG_ARM64)) {
 613                         dev_err(&pdev->dev, "MMIO base is invalid\n");
 614                         return -ENXIO;
 615                 }
 616                 error = pcim_iomap_regions(pdev, BIT(0), KBUILD_MODNAME);
 617                 if (error) {
 618                         dev_err(&pdev->dev, "Failed to reserve/map IO regions\n");
 619                         return error;
 620                 }
 621                 iobase = pcim_iomap_table(pdev)[0];
 622         }
 623
 624         vmci_dev = devm_kzalloc(&pdev->dev, sizeof(*vmci_dev), GFP_KERNEL);
 625         if (!vmci_dev) {
 626                 dev_err(&pdev->dev,
 627                         "Can't allocate memory for VMCI device\n");
 628                 return -ENOMEM;
 629         }
 630
 631         vmci_dev->dev = &pdev->dev;
 632         vmci_dev->exclusive_vectors = false;
 633         vmci_dev->iobase = iobase;
 634         vmci_dev->mmio_base = mmio_base;
 635
 636         init_waitqueue_head(&vmci_dev->inout_wq);
 637
 638         if (mmio_base != NULL) {
 639                 vmci_dev->tx_buffer = dma_alloc_coherent(&pdev->dev, VMCI_DMA_DG_BUFFER_SIZE,
 640                                                          &vmci_dev->tx_buffer_base,
 641                                                          GFP_KERNEL);
 642                 if (!vmci_dev->tx_buffer) {
 643                         dev_err(&pdev->dev,
 644                                 "Can't allocate memory for datagram tx buffer\n");
 645                         return -ENOMEM;
 646                 }
 647
 648                 vmci_dev->data_buffer = dma_alloc_coherent(&pdev->dev, VMCI_DMA_DG_BUFFER_SIZE,
 649                                                            &vmci_dev->data_buffer_base,
 650                                                            GFP_KERNEL);
 651         } else {
 652                 vmci_dev->data_buffer = vmalloc(VMCI_MAX_DG_SIZE);
 653         }
 654         if (!vmci_dev->data_buffer) {
 655                 dev_err(&pdev->dev,
 656                         "Can't allocate memory for datagram buffer\n");
 657                 error = -ENOMEM;
 658                 goto err_free_data_buffers;
 659         }
 660
 661         pci_set_master(pdev);   /* To enable queue_pair functionality. */
 662
 663         /*
 664          * Verify that the VMCI Device supports the capabilities that
 665          * we need. If the device is missing capabilities that we would
 666          * like to use, check for fallback capabilities and use those
 667          * instead (so we can run a new VM on old hosts). Fail the load if
 668          * a required capability is missing and there is no fallback.
 669          *
 670          * Right now, we need datagrams. There are no fallbacks.
 671          */
 672         capabilities = vmci_read_reg(vmci_dev, VMCI_CAPS_ADDR);
 673         if (!(capabilities & VMCI_CAPS_DATAGRAM)) {
 674                 dev_err(&pdev->dev, "Device does not support datagrams\n");
 675                 error = -ENXIO;
 676                 goto err_free_data_buffers;
 677         }
 678         caps_in_use = VMCI_CAPS_DATAGRAM;
 679
 680         /*
 681          * Use 64-bit PPNs if the device supports.
 682          *
 683          * There is no check for the return value of dma_set_mask_and_coherent
 684          * since this driver can handle the default mask values if
 685          * dma_set_mask_and_coherent fails.
 686          */
 687         if (capabilities & VMCI_CAPS_PPN64) {
 688                 dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
 689                 use_ppn64 = true;
 690                 caps_in_use |= VMCI_CAPS_PPN64;
 691         } else {
 692                 dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(44));
 693                 use_ppn64 = false;
 694         }
 695
 696         /*
 697          * If the hardware supports notifications, we will use that as
 698          * well.
 699          */
 700         if (capabilities & VMCI_CAPS_NOTIFICATIONS) {
 701                 vmci_dev->notification_bitmap = dma_alloc_coherent(
 702                         &pdev->dev, PAGE_SIZE, &vmci_dev->notification_base,
 703                         GFP_KERNEL);
 704                 if (!vmci_dev->notification_bitmap)
 705                         dev_warn(&pdev->dev,
 706                                  "Unable to allocate notification bitmap\n");
 707                 else
 708                         caps_in_use |= VMCI_CAPS_NOTIFICATIONS;
 709         }
 710
 711         if (mmio_base != NULL) {
 712                 if (capabilities & VMCI_CAPS_DMA_DATAGRAM) {
 713                         caps_in_use |= VMCI_CAPS_DMA_DATAGRAM;
 714                 } else {
 715                         dev_err(&pdev->dev,
 716                                 "Missing capability: VMCI_CAPS_DMA_DATAGRAM\n");
 717                         error = -ENXIO;
 718                         goto err_free_notification_bitmap;
 719                 }
 720         }
 721
 722         dev_info(&pdev->dev, "Using capabilities 0x%x\n", caps_in_use);
 723
 724         /* Let the host know which capabilities we intend to use. */
 725         vmci_write_reg(vmci_dev, caps_in_use, VMCI_CAPS_ADDR);
 726
 727         if (caps_in_use & VMCI_CAPS_DMA_DATAGRAM) {
 728                 /* Let the device know the size for pages passed down. */
 729                 vmci_write_reg(vmci_dev, PAGE_SHIFT, VMCI_GUEST_PAGE_SHIFT);
 730
 731                 /* Configure the high order parts of the data in/out buffers. */
 732                 vmci_write_reg(vmci_dev, upper_32_bits(vmci_dev->data_buffer_base),
 733                                VMCI_DATA_IN_HIGH_ADDR);
 734                 vmci_write_reg(vmci_dev, upper_32_bits(vmci_dev->tx_buffer_base),
 735                                VMCI_DATA_OUT_HIGH_ADDR);
 736         }
 737
 738         /* Set up global device so that we can start sending datagrams */
 739         spin_lock_irq(&vmci_dev_spinlock);
 740         vmci_dev_g = vmci_dev;
 741         vmci_pdev = pdev;
 742         spin_unlock_irq(&vmci_dev_spinlock);
 743
 744         /*
 745          * Register notification bitmap with device if that capability is
 746          * used.
 747          */
 748         if (caps_in_use & VMCI_CAPS_NOTIFICATIONS) {
 749                 unsigned long bitmap_ppn =
 750                         vmci_dev->notification_base >> PAGE_SHIFT;
 751                 if (!vmci_dbell_register_notification_bitmap(bitmap_ppn)) {
 752                         dev_warn(&pdev->dev,
 753                                  "VMCI device unable to register notification bitmap with PPN 0x%lx\n",
 754                                  bitmap_ppn);
 755                         error = -ENXIO;
 756                         goto err_remove_vmci_dev_g;
 757                 }
 758         }
 759
 760         /* Check host capabilities. */
 761         error = vmci_check_host_caps(pdev);
 762         if (error)
 763                 goto err_remove_vmci_dev_g;
 764
 765         /* Enable device. */
 766
 767         /*
 768          * We subscribe to the VMCI_EVENT_CTX_ID_UPDATE here so we can
 769          * update the internal context id when needed.
 770          */
 771         vmci_err = vmci_event_subscribe(VMCI_EVENT_CTX_ID_UPDATE,
 772                                         vmci_guest_cid_update, NULL,
 773                                         &ctx_update_sub_id);
 774         if (vmci_err < VMCI_SUCCESS)
 775                 dev_warn(&pdev->dev,
 776                          "Failed to subscribe to event (type=%d): %d\n",
 777                          VMCI_EVENT_CTX_ID_UPDATE, vmci_err);
 778
 779         /*
 780          * Enable interrupts.  Try MSI-X first, then MSI, and then fallback on
 781          * legacy interrupts.
 782          */
 783         if (vmci_dev->mmio_base != NULL)
 784                 num_irq_vectors = VMCI_MAX_INTRS;
 785         else
 786                 num_irq_vectors = VMCI_MAX_INTRS_NOTIFICATION;
 787         error = pci_alloc_irq_vectors(pdev, num_irq_vectors, num_irq_vectors,
 788                                       PCI_IRQ_MSIX);
 789         if (error < 0) {
 790                 error = pci_alloc_irq_vectors(pdev, 1, 1,
 791                                 PCI_IRQ_MSIX | PCI_IRQ_MSI | PCI_IRQ_LEGACY);
 792                 if (error < 0)
 793                         goto err_unsubscribe_event;
 794         } else {
 795                 vmci_dev->exclusive_vectors = true;
 796         }
 797
 798         /*
 799          * Request IRQ for legacy or MSI interrupts, or for first
 800          * MSI-X vector.
 801          */
 802         error = request_threaded_irq(pci_irq_vector(pdev, 0), NULL,
 803                                      vmci_interrupt, IRQF_SHARED,
 804                                      KBUILD_MODNAME, vmci_dev);
 805         if (error) {
 806                 dev_err(&pdev->dev, "Irq %u in use: %d\n",
 807                         pci_irq_vector(pdev, 0), error);
 808                 goto err_disable_msi;
 809         }
 810
 811         /*
 812          * For MSI-X with exclusive vectors we need to request an
 813          * interrupt for each vector so that we get a separate
 814          * interrupt handler routine.  This allows us to distinguish
 815          * between the vectors.
 816          */
 817         if (vmci_dev->exclusive_vectors) {
 818                 error = request_threaded_irq(pci_irq_vector(pdev, 1), NULL,
 819                                              vmci_interrupt_bm, 0,
 820                                              KBUILD_MODNAME, vmci_dev);
 821                 if (error) {
 822                         dev_err(&pdev->dev,
 823                                 "Failed to allocate irq %u: %d\n",
 824                                 pci_irq_vector(pdev, 1), error);
 825                         goto err_free_irq;
 826                 }
 827                 if (caps_in_use & VMCI_CAPS_DMA_DATAGRAM) {
 828                         error = request_threaded_irq(pci_irq_vector(pdev, 2),
 829                                                      NULL,
 830                                                     vmci_interrupt_dma_datagram,
 831                                                      0, KBUILD_MODNAME,
 832                                                      vmci_dev);
 833                         if (error) {
 834                                 dev_err(&pdev->dev,
 835                                         "Failed to allocate irq %u: %d\n",
 836                                         pci_irq_vector(pdev, 2), error);
 837                                 goto err_free_bm_irq;
 838                         }
 839                 }
 840         }
 841
 842         dev_dbg(&pdev->dev, "Registered device\n");
 843
 844         atomic_inc(&vmci_num_guest_devices);
 845
 846         /* Enable specific interrupt bits. */
 847         cmd = VMCI_IMR_DATAGRAM;
 848         if (caps_in_use & VMCI_CAPS_NOTIFICATIONS)
 849                 cmd |= VMCI_IMR_NOTIFICATION;
 850         if (caps_in_use & VMCI_CAPS_DMA_DATAGRAM)
 851                 cmd |= VMCI_IMR_DMA_DATAGRAM;
 852         vmci_write_reg(vmci_dev, cmd, VMCI_IMR_ADDR);
 853
 854         /* Enable interrupts. */
 855         vmci_write_reg(vmci_dev, VMCI_CONTROL_INT_ENABLE, VMCI_CONTROL_ADDR);
 856
 857         pci_set_drvdata(pdev, vmci_dev);
 858
 859         vmci_call_vsock_callback(false);
 860         return 0;
 861
 862 err_free_bm_irq:
 863         if (vmci_dev->exclusive_vectors)
 864                 free_irq(pci_irq_vector(pdev, 1), vmci_dev);
 865
 866 err_free_irq:
 867         free_irq(pci_irq_vector(pdev, 0), vmci_dev);
 868
 869 err_disable_msi:
 870         pci_free_irq_vectors(pdev);
 871
 872 err_unsubscribe_event:
 873         vmci_err = vmci_event_unsubscribe(ctx_update_sub_id);
 874         if (vmci_err < VMCI_SUCCESS)
 875                 dev_warn(&pdev->dev,
 876                          "Failed to unsubscribe from event (type=%d) with subscriber (ID=0x%x): %d\n",
 877                          VMCI_EVENT_CTX_ID_UPDATE, ctx_update_sub_id, vmci_err);
 878
 879 err_remove_vmci_dev_g:
 880         spin_lock_irq(&vmci_dev_spinlock);
 881         vmci_pdev = NULL;
 882         vmci_dev_g = NULL;
 883         spin_unlock_irq(&vmci_dev_spinlock);
 884
 885 err_free_notification_bitmap:
 886         if (vmci_dev->notification_bitmap) {
 887                 vmci_write_reg(vmci_dev, VMCI_CONTROL_RESET, VMCI_CONTROL_ADDR);
 888                 dma_free_coherent(&pdev->dev, PAGE_SIZE,
 889                                   vmci_dev->notification_bitmap,
 890                                   vmci_dev->notification_base);
 891         }
 892
 893 err_free_data_buffers:
 894         vmci_free_dg_buffers(vmci_dev);
 895
 896         /* The rest are managed resources and will be freed by PCI core */
 897         return error;
 898 }
 899
 900 static void vmci_guest_remove_device(struct pci_dev *pdev)
 901 {
 902         struct vmci_guest_device *vmci_dev = pci_get_drvdata(pdev);
 903         int vmci_err;
 904
 905         dev_dbg(&pdev->dev, "Removing device\n");
 906
 907         atomic_dec(&vmci_num_guest_devices);
 908
 909         vmci_qp_guest_endpoints_exit();
 910
 911         vmci_err = vmci_event_unsubscribe(ctx_update_sub_id);
 912         if (vmci_err < VMCI_SUCCESS)
 913                 dev_warn(&pdev->dev,
 914                          "Failed to unsubscribe from event (type=%d) with subscriber (ID=0x%x): %d\n",
 915                          VMCI_EVENT_CTX_ID_UPDATE, ctx_update_sub_id, vmci_err);
 916
 917         spin_lock_irq(&vmci_dev_spinlock);
 918         vmci_dev_g = NULL;
 919         vmci_pdev = NULL;
 920         spin_unlock_irq(&vmci_dev_spinlock);
 921
 922         dev_dbg(&pdev->dev, "Resetting vmci device\n");
 923         vmci_write_reg(vmci_dev, VMCI_CONTROL_RESET, VMCI_CONTROL_ADDR);
 924
 925         /*
 926          * Free IRQ and then disable MSI/MSI-X as appropriate.  For
 927          * MSI-X, we might have multiple vectors, each with their own
 928          * IRQ, which we must free too.
 929          */
 930         if (vmci_dev->exclusive_vectors) {
 931                 free_irq(pci_irq_vector(pdev, 1), vmci_dev);
 932                 if (vmci_dev->mmio_base != NULL)
 933                         free_irq(pci_irq_vector(pdev, 2), vmci_dev);
 934         }
 935         free_irq(pci_irq_vector(pdev, 0), vmci_dev);
 936         pci_free_irq_vectors(pdev);
 937
 938         if (vmci_dev->notification_bitmap) {
 939                 /*
 940                  * The device reset above cleared the bitmap state of the
 941                  * device, so we can safely free it here.
 942                  */
 943
 944                 dma_free_coherent(&pdev->dev, PAGE_SIZE,
 945                                   vmci_dev->notification_bitmap,
 946                                   vmci_dev->notification_base);
 947         }
 948
 949         vmci_free_dg_buffers(vmci_dev);
 950
 951         if (vmci_dev->mmio_base != NULL)
 952                 pci_iounmap(pdev, vmci_dev->mmio_base);
 953
 954         /* The rest are managed resources and will be freed by PCI core */
 955 }
 956
 957 static const struct pci_device_id vmci_ids[] = {
 958         { PCI_DEVICE(PCI_VENDOR_ID_VMWARE, PCI_DEVICE_ID_VMWARE_VMCI), },
 959         { 0 },
 960 };
 961 MODULE_DEVICE_TABLE(pci, vmci_ids);
 962
 963 static struct pci_driver vmci_guest_driver = {
 964         .name           = KBUILD_MODNAME,
 965         .id_table       = vmci_ids,
 966         .probe          = vmci_guest_probe_device,
 967         .remove         = vmci_guest_remove_device,
 968 };
 969
 970 int __init vmci_guest_init(void)
 971 {
 972         return pci_register_driver(&vmci_guest_driver);
 973 }
 974
 975 void __exit vmci_guest_exit(void)
 976 {
 977         pci_unregister_driver(&vmci_guest_driver);
 978 }