1 /*
2  * VMware VMCI Driver
3  *
4  * Copyright (C) 2012 VMware, Inc. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the
8  * Free Software Foundation version 2 and no later version.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13  * for more details.
14  */
15 
16 #include <linux/vmw_vmci_defs.h>
17 #include <linux/vmw_vmci_api.h>
18 #include <linux/moduleparam.h>
19 #include <linux/interrupt.h>
20 #include <linux/highmem.h>
21 #include <linux/kernel.h>
22 #include <linux/mm.h>
23 #include <linux/module.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/pci.h>
28 #include <linux/smp.h>
29 #include <linux/io.h>
30 #include <linux/vmalloc.h>
31 
32 #include "vmci_datagram.h"
33 #include "vmci_doorbell.h"
34 #include "vmci_context.h"
35 #include "vmci_driver.h"
36 #include "vmci_event.h"
37 
38 #define PCI_VENDOR_ID_VMWARE		0x15AD
39 #define PCI_DEVICE_ID_VMWARE_VMCI	0x0740
40 
41 #define VMCI_UTIL_NUM_RESOURCES 1
42 
43 static bool vmci_disable_msi;
44 module_param_named(disable_msi, vmci_disable_msi, bool, 0);
45 MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
46 
47 static bool vmci_disable_msix;
48 module_param_named(disable_msix, vmci_disable_msix, bool, 0);
49 MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
50 
51 static u32 ctx_update_sub_id = VMCI_INVALID_ID;
52 static u32 vm_context_id = VMCI_INVALID_ID;
53 
54 struct vmci_guest_device {
55 	struct device *dev;	/* PCI device we are attached to */
56 	void __iomem *iobase;
57 
58 	unsigned int irq;
59 	unsigned int intr_type;
60 	bool exclusive_vectors;
61 	struct msix_entry msix_entries[VMCI_MAX_INTRS];
62 
63 	struct tasklet_struct datagram_tasklet;
64 	struct tasklet_struct bm_tasklet;
65 
66 	void *data_buffer;
67 	void *notification_bitmap;
68 	dma_addr_t notification_base;
69 };
70 
71 /* vmci_dev singleton device and supporting data*/
72 struct pci_dev *vmci_pdev;
73 static struct vmci_guest_device *vmci_dev_g;
74 static DEFINE_SPINLOCK(vmci_dev_spinlock);
75 
76 static atomic_t vmci_num_guest_devices = ATOMIC_INIT(0);
77 
78 bool vmci_guest_code_active(void)
79 {
80 	return atomic_read(&vmci_num_guest_devices) != 0;
81 }
82 
83 u32 vmci_get_vm_context_id(void)
84 {
85 	if (vm_context_id == VMCI_INVALID_ID) {
86 		struct vmci_datagram get_cid_msg;
87 		get_cid_msg.dst =
88 		    vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
89 				     VMCI_GET_CONTEXT_ID);
90 		get_cid_msg.src = VMCI_ANON_SRC_HANDLE;
91 		get_cid_msg.payload_size = 0;
92 		vm_context_id = vmci_send_datagram(&get_cid_msg);
93 	}
94 	return vm_context_id;
95 }
96 
97 /*
98  * VM to hypervisor call mechanism. We use the standard VMware naming
99  * convention since shared code is calling this function as well.
100  */
101 int vmci_send_datagram(struct vmci_datagram *dg)
102 {
103 	unsigned long flags;
104 	int result;
105 
106 	/* Check args. */
107 	if (dg == NULL)
108 		return VMCI_ERROR_INVALID_ARGS;
109 
110 	/*
111 	 * Need to acquire spinlock on the device because the datagram
112 	 * data may be spread over multiple pages and the monitor may
113 	 * interleave device user rpc calls from multiple
114 	 * VCPUs. Acquiring the spinlock precludes that
115 	 * possibility. Disabling interrupts to avoid incoming
116 	 * datagrams during a "rep out" and possibly landing up in
117 	 * this function.
118 	 */
119 	spin_lock_irqsave(&vmci_dev_spinlock, flags);
120 
121 	if (vmci_dev_g) {
122 		iowrite8_rep(vmci_dev_g->iobase + VMCI_DATA_OUT_ADDR,
123 			     dg, VMCI_DG_SIZE(dg));
124 		result = ioread32(vmci_dev_g->iobase + VMCI_RESULT_LOW_ADDR);
125 	} else {
126 		result = VMCI_ERROR_UNAVAILABLE;
127 	}
128 
129 	spin_unlock_irqrestore(&vmci_dev_spinlock, flags);
130 
131 	return result;
132 }
133 EXPORT_SYMBOL_GPL(vmci_send_datagram);
134 
135 /*
136  * Gets called with the new context id if updated or resumed.
137  * Context id.
138  */
139 static void vmci_guest_cid_update(u32 sub_id,
140 				  const struct vmci_event_data *event_data,
141 				  void *client_data)
142 {
143 	const struct vmci_event_payld_ctx *ev_payload =
144 				vmci_event_data_const_payload(event_data);
145 
146 	if (sub_id != ctx_update_sub_id) {
147 		pr_devel("Invalid subscriber (ID=0x%x)\n", sub_id);
148 		return;
149 	}
150 
151 	if (!event_data || ev_payload->context_id == VMCI_INVALID_ID) {
152 		pr_devel("Invalid event data\n");
153 		return;
154 	}
155 
156 	pr_devel("Updating context from (ID=0x%x) to (ID=0x%x) on event (type=%d)\n",
157 		 vm_context_id, ev_payload->context_id, event_data->event);
158 
159 	vm_context_id = ev_payload->context_id;
160 }
161 
162 /*
163  * Verify that the host supports the hypercalls we need. If it does not,
164  * try to find fallback hypercalls and use those instead.  Returns
165  * true if required hypercalls (or fallback hypercalls) are
166  * supported by the host, false otherwise.
167  */
168 static bool vmci_check_host_caps(struct pci_dev *pdev)
169 {
170 	bool result;
171 	struct vmci_resource_query_msg *msg;
172 	u32 msg_size = sizeof(struct vmci_resource_query_hdr) +
173 				VMCI_UTIL_NUM_RESOURCES * sizeof(u32);
174 	struct vmci_datagram *check_msg;
175 
176 	check_msg = kmalloc(msg_size, GFP_KERNEL);
177 	if (!check_msg) {
178 		dev_err(&pdev->dev, "%s: Insufficient memory\n", __func__);
179 		return false;
180 	}
181 
182 	check_msg->dst = vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,
183 					  VMCI_RESOURCES_QUERY);
184 	check_msg->src = VMCI_ANON_SRC_HANDLE;
185 	check_msg->payload_size = msg_size - VMCI_DG_HEADERSIZE;
186 	msg = (struct vmci_resource_query_msg *)VMCI_DG_PAYLOAD(check_msg);
187 
188 	msg->num_resources = VMCI_UTIL_NUM_RESOURCES;
189 	msg->resources[0] = VMCI_GET_CONTEXT_ID;
190 
191 	/* Checks that hyper calls are supported */
192 	result = vmci_send_datagram(check_msg) == 0x01;
193 	kfree(check_msg);
194 
195 	dev_dbg(&pdev->dev, "%s: Host capability check: %s\n",
196 		__func__, result ? "PASSED" : "FAILED");
197 
198 	/* We need the vector. There are no fallbacks. */
199 	return result;
200 }
201 
202 /*
203  * Reads datagrams from the data in port and dispatches them. We
204  * always start reading datagrams into only the first page of the
205  * datagram buffer. If the datagrams don't fit into one page, we
206  * use the maximum datagram buffer size for the remainder of the
207  * invocation. This is a simple heuristic for not penalizing
208  * small datagrams.
209  *
210  * This function assumes that it has exclusive access to the data
211  * in port for the duration of the call.
212  */
213 static void vmci_dispatch_dgs(unsigned long data)
214 {
215 	struct vmci_guest_device *vmci_dev = (struct vmci_guest_device *)data;
216 	u8 *dg_in_buffer = vmci_dev->data_buffer;
217 	struct vmci_datagram *dg;
218 	size_t dg_in_buffer_size = VMCI_MAX_DG_SIZE;
219 	size_t current_dg_in_buffer_size = PAGE_SIZE;
220 	size_t remaining_bytes;
221 
222 	BUILD_BUG_ON(VMCI_MAX_DG_SIZE < PAGE_SIZE);
223 
224 	ioread8_rep(vmci_dev->iobase + VMCI_DATA_IN_ADDR,
225 		    vmci_dev->data_buffer, current_dg_in_buffer_size);
226 	dg = (struct vmci_datagram *)dg_in_buffer;
227 	remaining_bytes = current_dg_in_buffer_size;
228 
229 	while (dg->dst.resource != VMCI_INVALID_ID ||
230 	       remaining_bytes > PAGE_SIZE) {
231 		unsigned dg_in_size;
232 
233 		/*
234 		 * When the input buffer spans multiple pages, a datagram can
235 		 * start on any page boundary in the buffer.
236 		 */
237 		if (dg->dst.resource == VMCI_INVALID_ID) {
238 			dg = (struct vmci_datagram *)roundup(
239 				(uintptr_t)dg + 1, PAGE_SIZE);
240 			remaining_bytes =
241 				(size_t)(dg_in_buffer +
242 					 current_dg_in_buffer_size -
243 					 (u8 *)dg);
244 			continue;
245 		}
246 
247 		dg_in_size = VMCI_DG_SIZE_ALIGNED(dg);
248 
249 		if (dg_in_size <= dg_in_buffer_size) {
250 			int result;
251 
252 			/*
253 			 * If the remaining bytes in the datagram
254 			 * buffer doesn't contain the complete
255 			 * datagram, we first make sure we have enough
256 			 * room for it and then we read the reminder
257 			 * of the datagram and possibly any following
258 			 * datagrams.
259 			 */
260 			if (dg_in_size > remaining_bytes) {
261 				if (remaining_bytes !=
262 				    current_dg_in_buffer_size) {
263 
264 					/*
265 					 * We move the partial
266 					 * datagram to the front and
267 					 * read the reminder of the
268 					 * datagram and possibly
269 					 * following calls into the
270 					 * following bytes.
271 					 */
272 					memmove(dg_in_buffer, dg_in_buffer +
273 						current_dg_in_buffer_size -
274 						remaining_bytes,
275 						remaining_bytes);
276 					dg = (struct vmci_datagram *)
277 					    dg_in_buffer;
278 				}
279 
280 				if (current_dg_in_buffer_size !=
281 				    dg_in_buffer_size)
282 					current_dg_in_buffer_size =
283 					    dg_in_buffer_size;
284 
285 				ioread8_rep(vmci_dev->iobase +
286 						VMCI_DATA_IN_ADDR,
287 					vmci_dev->data_buffer +
288 						remaining_bytes,
289 					current_dg_in_buffer_size -
290 						remaining_bytes);
291 			}
292 
293 			/*
294 			 * We special case event datagrams from the
295 			 * hypervisor.
296 			 */
297 			if (dg->src.context == VMCI_HYPERVISOR_CONTEXT_ID &&
298 			    dg->dst.resource == VMCI_EVENT_HANDLER) {
299 				result = vmci_event_dispatch(dg);
300 			} else {
301 				result = vmci_datagram_invoke_guest_handler(dg);
302 			}
303 			if (result < VMCI_SUCCESS)
304 				dev_dbg(vmci_dev->dev,
305 					"Datagram with resource (ID=0x%x) failed (err=%d)\n",
306 					 dg->dst.resource, result);
307 
308 			/* On to the next datagram. */
309 			dg = (struct vmci_datagram *)((u8 *)dg +
310 						      dg_in_size);
311 		} else {
312 			size_t bytes_to_skip;
313 
314 			/*
315 			 * Datagram doesn't fit in datagram buffer of maximal
316 			 * size. We drop it.
317 			 */
318 			dev_dbg(vmci_dev->dev,
319 				"Failed to receive datagram (size=%u bytes)\n",
320 				 dg_in_size);
321 
322 			bytes_to_skip = dg_in_size - remaining_bytes;
323 			if (current_dg_in_buffer_size != dg_in_buffer_size)
324 				current_dg_in_buffer_size = dg_in_buffer_size;
325 
326 			for (;;) {
327 				ioread8_rep(vmci_dev->iobase +
328 						VMCI_DATA_IN_ADDR,
329 					vmci_dev->data_buffer,
330 					current_dg_in_buffer_size);
331 				if (bytes_to_skip <= current_dg_in_buffer_size)
332 					break;
333 
334 				bytes_to_skip -= current_dg_in_buffer_size;
335 			}
336 			dg = (struct vmci_datagram *)(dg_in_buffer +
337 						      bytes_to_skip);
338 		}
339 
340 		remaining_bytes =
341 		    (size_t) (dg_in_buffer + current_dg_in_buffer_size -
342 			      (u8 *)dg);
343 
344 		if (remaining_bytes < VMCI_DG_HEADERSIZE) {
345 			/* Get the next batch of datagrams. */
346 
347 			ioread8_rep(vmci_dev->iobase + VMCI_DATA_IN_ADDR,
348 				    vmci_dev->data_buffer,
349 				    current_dg_in_buffer_size);
350 			dg = (struct vmci_datagram *)dg_in_buffer;
351 			remaining_bytes = current_dg_in_buffer_size;
352 		}
353 	}
354 }
355 
356 /*
357  * Scans the notification bitmap for raised flags, clears them
358  * and handles the notifications.
359  */
360 static void vmci_process_bitmap(unsigned long data)
361 {
362 	struct vmci_guest_device *dev = (struct vmci_guest_device *)data;
363 
364 	if (!dev->notification_bitmap) {
365 		dev_dbg(dev->dev, "No bitmap present in %s\n", __func__);
366 		return;
367 	}
368 
369 	vmci_dbell_scan_notification_entries(dev->notification_bitmap);
370 }
371 
372 /*
373  * Enable MSI-X.  Try exclusive vectors first, then shared vectors.
374  */
375 static int vmci_enable_msix(struct pci_dev *pdev,
376 			    struct vmci_guest_device *vmci_dev)
377 {
378 	int i;
379 	int result;
380 
381 	for (i = 0; i < VMCI_MAX_INTRS; ++i) {
382 		vmci_dev->msix_entries[i].entry = i;
383 		vmci_dev->msix_entries[i].vector = i;
384 	}
385 
386 	result = pci_enable_msix(pdev, vmci_dev->msix_entries, VMCI_MAX_INTRS);
387 	if (result == 0)
388 		vmci_dev->exclusive_vectors = true;
389 	else if (result > 0)
390 		result = pci_enable_msix(pdev, vmci_dev->msix_entries, 1);
391 
392 	return result;
393 }
394 
395 /*
396  * Interrupt handler for legacy or MSI interrupt, or for first MSI-X
397  * interrupt (vector VMCI_INTR_DATAGRAM).
398  */
399 static irqreturn_t vmci_interrupt(int irq, void *_dev)
400 {
401 	struct vmci_guest_device *dev = _dev;
402 
403 	/*
404 	 * If we are using MSI-X with exclusive vectors then we simply schedule
405 	 * the datagram tasklet, since we know the interrupt was meant for us.
406 	 * Otherwise we must read the ICR to determine what to do.
407 	 */
408 
409 	if (dev->intr_type == VMCI_INTR_TYPE_MSIX && dev->exclusive_vectors) {
410 		tasklet_schedule(&dev->datagram_tasklet);
411 	} else {
412 		unsigned int icr;
413 
414 		/* Acknowledge interrupt and determine what needs doing. */
415 		icr = ioread32(dev->iobase + VMCI_ICR_ADDR);
416 		if (icr == 0 || icr == ~0)
417 			return IRQ_NONE;
418 
419 		if (icr & VMCI_ICR_DATAGRAM) {
420 			tasklet_schedule(&dev->datagram_tasklet);
421 			icr &= ~VMCI_ICR_DATAGRAM;
422 		}
423 
424 		if (icr & VMCI_ICR_NOTIFICATION) {
425 			tasklet_schedule(&dev->bm_tasklet);
426 			icr &= ~VMCI_ICR_NOTIFICATION;
427 		}
428 
429 		if (icr != 0)
430 			dev_warn(dev->dev,
431 				 "Ignoring unknown interrupt cause (%d)\n",
432 				 icr);
433 	}
434 
435 	return IRQ_HANDLED;
436 }
437 
438 /*
439  * Interrupt handler for MSI-X interrupt vector VMCI_INTR_NOTIFICATION,
440  * which is for the notification bitmap.  Will only get called if we are
441  * using MSI-X with exclusive vectors.
442  */
443 static irqreturn_t vmci_interrupt_bm(int irq, void *_dev)
444 {
445 	struct vmci_guest_device *dev = _dev;
446 
447 	/* For MSI-X we can just assume it was meant for us. */
448 	tasklet_schedule(&dev->bm_tasklet);
449 
450 	return IRQ_HANDLED;
451 }
452 
453 /*
454  * Most of the initialization at module load time is done here.
455  */
456 static int vmci_guest_probe_device(struct pci_dev *pdev,
457 				   const struct pci_device_id *id)
458 {
459 	struct vmci_guest_device *vmci_dev;
460 	void __iomem *iobase;
461 	unsigned int capabilities;
462 	unsigned long cmd;
463 	int vmci_err;
464 	int error;
465 
466 	dev_dbg(&pdev->dev, "Probing for vmci/PCI guest device\n");
467 
468 	error = pcim_enable_device(pdev);
469 	if (error) {
470 		dev_err(&pdev->dev,
471 			"Failed to enable VMCI device: %d\n", error);
472 		return error;
473 	}
474 
475 	error = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
476 	if (error) {
477 		dev_err(&pdev->dev, "Failed to reserve/map IO regions\n");
478 		return error;
479 	}
480 
481 	iobase = pcim_iomap_table(pdev)[0];
482 
483 	dev_info(&pdev->dev, "Found VMCI PCI device at %#lx, irq %u\n",
484 		 (unsigned long)iobase, pdev->irq);
485 
486 	vmci_dev = devm_kzalloc(&pdev->dev, sizeof(*vmci_dev), GFP_KERNEL);
487 	if (!vmci_dev) {
488 		dev_err(&pdev->dev,
489 			"Can't allocate memory for VMCI device\n");
490 		return -ENOMEM;
491 	}
492 
493 	vmci_dev->dev = &pdev->dev;
494 	vmci_dev->intr_type = VMCI_INTR_TYPE_INTX;
495 	vmci_dev->exclusive_vectors = false;
496 	vmci_dev->iobase = iobase;
497 
498 	tasklet_init(&vmci_dev->datagram_tasklet,
499 		     vmci_dispatch_dgs, (unsigned long)vmci_dev);
500 	tasklet_init(&vmci_dev->bm_tasklet,
501 		     vmci_process_bitmap, (unsigned long)vmci_dev);
502 
503 	vmci_dev->data_buffer = vmalloc(VMCI_MAX_DG_SIZE);
504 	if (!vmci_dev->data_buffer) {
505 		dev_err(&pdev->dev,
506 			"Can't allocate memory for datagram buffer\n");
507 		return -ENOMEM;
508 	}
509 
510 	pci_set_master(pdev);	/* To enable queue_pair functionality. */
511 
512 	/*
513 	 * Verify that the VMCI Device supports the capabilities that
514 	 * we need. If the device is missing capabilities that we would
515 	 * like to use, check for fallback capabilities and use those
516 	 * instead (so we can run a new VM on old hosts). Fail the load if
517 	 * a required capability is missing and there is no fallback.
518 	 *
519 	 * Right now, we need datagrams. There are no fallbacks.
520 	 */
521 	capabilities = ioread32(vmci_dev->iobase + VMCI_CAPS_ADDR);
522 	if (!(capabilities & VMCI_CAPS_DATAGRAM)) {
523 		dev_err(&pdev->dev, "Device does not support datagrams\n");
524 		error = -ENXIO;
525 		goto err_free_data_buffer;
526 	}
527 
528 	/*
529 	 * If the hardware supports notifications, we will use that as
530 	 * well.
531 	 */
532 	if (capabilities & VMCI_CAPS_NOTIFICATIONS) {
533 		vmci_dev->notification_bitmap = dma_alloc_coherent(
534 			&pdev->dev, PAGE_SIZE, &vmci_dev->notification_base,
535 			GFP_KERNEL);
536 		if (!vmci_dev->notification_bitmap) {
537 			dev_warn(&pdev->dev,
538 				 "Unable to allocate notification bitmap\n");
539 		} else {
540 			memset(vmci_dev->notification_bitmap, 0, PAGE_SIZE);
541 			capabilities |= VMCI_CAPS_NOTIFICATIONS;
542 		}
543 	}
544 
545 	dev_info(&pdev->dev, "Using capabilities 0x%x\n", capabilities);
546 
547 	/* Let the host know which capabilities we intend to use. */
548 	iowrite32(capabilities, vmci_dev->iobase + VMCI_CAPS_ADDR);
549 
550 	/* Set up global device so that we can start sending datagrams */
551 	spin_lock_irq(&vmci_dev_spinlock);
552 	vmci_dev_g = vmci_dev;
553 	vmci_pdev = pdev;
554 	spin_unlock_irq(&vmci_dev_spinlock);
555 
556 	/*
557 	 * Register notification bitmap with device if that capability is
558 	 * used.
559 	 */
560 	if (capabilities & VMCI_CAPS_NOTIFICATIONS) {
561 		unsigned long bitmap_ppn =
562 			vmci_dev->notification_base >> PAGE_SHIFT;
563 		if (!vmci_dbell_register_notification_bitmap(bitmap_ppn)) {
564 			dev_warn(&pdev->dev,
565 				 "VMCI device unable to register notification bitmap with PPN 0x%x\n",
566 				 (u32) bitmap_ppn);
567 			goto err_remove_vmci_dev_g;
568 		}
569 	}
570 
571 	/* Check host capabilities. */
572 	if (!vmci_check_host_caps(pdev))
573 		goto err_remove_bitmap;
574 
575 	/* Enable device. */
576 
577 	/*
578 	 * We subscribe to the VMCI_EVENT_CTX_ID_UPDATE here so we can
579 	 * update the internal context id when needed.
580 	 */
581 	vmci_err = vmci_event_subscribe(VMCI_EVENT_CTX_ID_UPDATE,
582 					vmci_guest_cid_update, NULL,
583 					&ctx_update_sub_id);
584 	if (vmci_err < VMCI_SUCCESS)
585 		dev_warn(&pdev->dev,
586 			 "Failed to subscribe to event (type=%d): %d\n",
587 			 VMCI_EVENT_CTX_ID_UPDATE, vmci_err);
588 
589 	/*
590 	 * Enable interrupts.  Try MSI-X first, then MSI, and then fallback on
591 	 * legacy interrupts.
592 	 */
593 	if (!vmci_disable_msix && !vmci_enable_msix(pdev, vmci_dev)) {
594 		vmci_dev->intr_type = VMCI_INTR_TYPE_MSIX;
595 		vmci_dev->irq = vmci_dev->msix_entries[0].vector;
596 	} else if (!vmci_disable_msi && !pci_enable_msi(pdev)) {
597 		vmci_dev->intr_type = VMCI_INTR_TYPE_MSI;
598 		vmci_dev->irq = pdev->irq;
599 	} else {
600 		vmci_dev->intr_type = VMCI_INTR_TYPE_INTX;
601 		vmci_dev->irq = pdev->irq;
602 	}
603 
604 	/*
605 	 * Request IRQ for legacy or MSI interrupts, or for first
606 	 * MSI-X vector.
607 	 */
608 	error = request_irq(vmci_dev->irq, vmci_interrupt, IRQF_SHARED,
609 			    KBUILD_MODNAME, vmci_dev);
610 	if (error) {
611 		dev_err(&pdev->dev, "Irq %u in use: %d\n",
612 			vmci_dev->irq, error);
613 		goto err_disable_msi;
614 	}
615 
616 	/*
617 	 * For MSI-X with exclusive vectors we need to request an
618 	 * interrupt for each vector so that we get a separate
619 	 * interrupt handler routine.  This allows us to distinguish
620 	 * between the vectors.
621 	 */
622 	if (vmci_dev->exclusive_vectors) {
623 		error = request_irq(vmci_dev->msix_entries[1].vector,
624 				    vmci_interrupt_bm, 0, KBUILD_MODNAME,
625 				    vmci_dev);
626 		if (error) {
627 			dev_err(&pdev->dev,
628 				"Failed to allocate irq %u: %d\n",
629 				vmci_dev->msix_entries[1].vector, error);
630 			goto err_free_irq;
631 		}
632 	}
633 
634 	dev_dbg(&pdev->dev, "Registered device\n");
635 
636 	atomic_inc(&vmci_num_guest_devices);
637 
638 	/* Enable specific interrupt bits. */
639 	cmd = VMCI_IMR_DATAGRAM;
640 	if (capabilities & VMCI_CAPS_NOTIFICATIONS)
641 		cmd |= VMCI_IMR_NOTIFICATION;
642 	iowrite32(cmd, vmci_dev->iobase + VMCI_IMR_ADDR);
643 
644 	/* Enable interrupts. */
645 	iowrite32(VMCI_CONTROL_INT_ENABLE,
646 		  vmci_dev->iobase + VMCI_CONTROL_ADDR);
647 
648 	pci_set_drvdata(pdev, vmci_dev);
649 	return 0;
650 
651 err_free_irq:
652 	free_irq(vmci_dev->irq, vmci_dev);
653 	tasklet_kill(&vmci_dev->datagram_tasklet);
654 	tasklet_kill(&vmci_dev->bm_tasklet);
655 
656 err_disable_msi:
657 	if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSIX)
658 		pci_disable_msix(pdev);
659 	else if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSI)
660 		pci_disable_msi(pdev);
661 
662 	vmci_err = vmci_event_unsubscribe(ctx_update_sub_id);
663 	if (vmci_err < VMCI_SUCCESS)
664 		dev_warn(&pdev->dev,
665 			 "Failed to unsubscribe from event (type=%d) with subscriber (ID=0x%x): %d\n",
666 			 VMCI_EVENT_CTX_ID_UPDATE, ctx_update_sub_id, vmci_err);
667 
668 err_remove_bitmap:
669 	if (vmci_dev->notification_bitmap) {
670 		iowrite32(VMCI_CONTROL_RESET,
671 			  vmci_dev->iobase + VMCI_CONTROL_ADDR);
672 		dma_free_coherent(&pdev->dev, PAGE_SIZE,
673 				  vmci_dev->notification_bitmap,
674 				  vmci_dev->notification_base);
675 	}
676 
677 err_remove_vmci_dev_g:
678 	spin_lock_irq(&vmci_dev_spinlock);
679 	vmci_pdev = NULL;
680 	vmci_dev_g = NULL;
681 	spin_unlock_irq(&vmci_dev_spinlock);
682 
683 err_free_data_buffer:
684 	vfree(vmci_dev->data_buffer);
685 
686 	/* The rest are managed resources and will be freed by PCI core */
687 	return error;
688 }
689 
690 static void vmci_guest_remove_device(struct pci_dev *pdev)
691 {
692 	struct vmci_guest_device *vmci_dev = pci_get_drvdata(pdev);
693 	int vmci_err;
694 
695 	dev_dbg(&pdev->dev, "Removing device\n");
696 
697 	atomic_dec(&vmci_num_guest_devices);
698 
699 	vmci_qp_guest_endpoints_exit();
700 
701 	vmci_err = vmci_event_unsubscribe(ctx_update_sub_id);
702 	if (vmci_err < VMCI_SUCCESS)
703 		dev_warn(&pdev->dev,
704 			 "Failed to unsubscribe from event (type=%d) with subscriber (ID=0x%x): %d\n",
705 			 VMCI_EVENT_CTX_ID_UPDATE, ctx_update_sub_id, vmci_err);
706 
707 	spin_lock_irq(&vmci_dev_spinlock);
708 	vmci_dev_g = NULL;
709 	vmci_pdev = NULL;
710 	spin_unlock_irq(&vmci_dev_spinlock);
711 
712 	dev_dbg(&pdev->dev, "Resetting vmci device\n");
713 	iowrite32(VMCI_CONTROL_RESET, vmci_dev->iobase + VMCI_CONTROL_ADDR);
714 
715 	/*
716 	 * Free IRQ and then disable MSI/MSI-X as appropriate.  For
717 	 * MSI-X, we might have multiple vectors, each with their own
718 	 * IRQ, which we must free too.
719 	 */
720 	free_irq(vmci_dev->irq, vmci_dev);
721 	if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSIX) {
722 		if (vmci_dev->exclusive_vectors)
723 			free_irq(vmci_dev->msix_entries[1].vector, vmci_dev);
724 		pci_disable_msix(pdev);
725 	} else if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSI) {
726 		pci_disable_msi(pdev);
727 	}
728 
729 	tasklet_kill(&vmci_dev->datagram_tasklet);
730 	tasklet_kill(&vmci_dev->bm_tasklet);
731 
732 	if (vmci_dev->notification_bitmap) {
733 		/*
734 		 * The device reset above cleared the bitmap state of the
735 		 * device, so we can safely free it here.
736 		 */
737 
738 		dma_free_coherent(&pdev->dev, PAGE_SIZE,
739 				  vmci_dev->notification_bitmap,
740 				  vmci_dev->notification_base);
741 	}
742 
743 	vfree(vmci_dev->data_buffer);
744 
745 	/* The rest are managed resources and will be freed by PCI core */
746 }
747 
748 static DEFINE_PCI_DEVICE_TABLE(vmci_ids) = {
749 	{ PCI_DEVICE(PCI_VENDOR_ID_VMWARE, PCI_DEVICE_ID_VMWARE_VMCI), },
750 	{ 0 },
751 };
752 MODULE_DEVICE_TABLE(pci, vmci_ids);
753 
754 static struct pci_driver vmci_guest_driver = {
755 	.name		= KBUILD_MODNAME,
756 	.id_table	= vmci_ids,
757 	.probe		= vmci_guest_probe_device,
758 	.remove		= vmci_guest_remove_device,
759 };
760 
761 int __init vmci_guest_init(void)
762 {
763 	return pci_register_driver(&vmci_guest_driver);
764 }
765 
766 void __exit vmci_guest_exit(void)
767 {
768 	pci_unregister_driver(&vmci_guest_driver);
769 }
770