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
vmci_use_ppn64(void)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
vmci_guest_code_active(void)83 bool vmci_guest_code_active(void)
84 {
85 return atomic_read(&vmci_num_guest_devices) != 0;
86 }
87
vmci_get_vm_context_id(void)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
vmci_read_reg(struct vmci_guest_device * dev,u32 reg)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
vmci_write_reg(struct vmci_guest_device * dev,u32 val,u32 reg)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
vmci_read_data(struct vmci_guest_device * vmci_dev,void * dest,size_t size)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
vmci_write_data(struct vmci_guest_device * dev,struct vmci_datagram * dg)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 */
vmci_send_datagram(struct vmci_datagram * dg)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 */
vmci_guest_cid_update(u32 sub_id,const struct vmci_event_data * event_data,void * client_data)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 */
vmci_check_host_caps(struct pci_dev * pdev)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 */
vmci_dispatch_dgs(struct vmci_guest_device * vmci_dev)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 */
vmci_process_bitmap(struct vmci_guest_device * dev)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 */
vmci_interrupt(int irq,void * _dev)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 */
vmci_interrupt_bm(int irq,void * _dev)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 */
vmci_interrupt_dma_datagram(int irq,void * _dev)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
vmci_free_dg_buffers(struct vmci_guest_device * vmci_dev)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 */
vmci_guest_probe_device(struct pci_dev * pdev,const struct pci_device_id * id)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
vmci_guest_remove_device(struct pci_dev * pdev)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
vmci_guest_init(void)970 int __init vmci_guest_init(void)
971 {
972 return pci_register_driver(&vmci_guest_driver);
973 }
974
vmci_guest_exit(void)975 void __exit vmci_guest_exit(void)
976 {
977 pci_unregister_driver(&vmci_guest_driver);
978 }
979