xref: /openbmc/linux/drivers/misc/vmw_vmci/vmci_host.c (revision 44ad3baf1cca483e418b6aadf2d3994f69e0f16a)
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/miscdevice.h>
11 #include <linux/interrupt.h>
12 #include <linux/highmem.h>
13 #include <linux/atomic.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/sched.h>
18 #include <linux/cred.h>
19 #include <linux/slab.h>
20 #include <linux/file.h>
21 #include <linux/init.h>
22 #include <linux/poll.h>
23 #include <linux/pci.h>
24 #include <linux/smp.h>
25 #include <linux/fs.h>
26 #include <linux/io.h>
27 
28 #include "vmci_handle_array.h"
29 #include "vmci_queue_pair.h"
30 #include "vmci_datagram.h"
31 #include "vmci_doorbell.h"
32 #include "vmci_resource.h"
33 #include "vmci_context.h"
34 #include "vmci_driver.h"
35 #include "vmci_event.h"
36 
37 #define VMCI_UTIL_NUM_RESOURCES 1
38 
39 enum {
40 	VMCI_NOTIFY_RESOURCE_QUEUE_PAIR = 0,
41 	VMCI_NOTIFY_RESOURCE_DOOR_BELL = 1,
42 };
43 
44 enum {
45 	VMCI_NOTIFY_RESOURCE_ACTION_NOTIFY = 0,
46 	VMCI_NOTIFY_RESOURCE_ACTION_CREATE = 1,
47 	VMCI_NOTIFY_RESOURCE_ACTION_DESTROY = 2,
48 };
49 
50 /*
51  * VMCI driver initialization. This block can also be used to
52  * pass initial group membership etc.
53  */
54 struct vmci_init_blk {
55 	u32 cid;
56 	u32 flags;
57 };
58 
59 /* VMCIqueue_pairAllocInfo_VMToVM */
60 struct vmci_qp_alloc_info_vmvm {
61 	struct vmci_handle handle;
62 	u32 peer;
63 	u32 flags;
64 	u64 produce_size;
65 	u64 consume_size;
66 	u64 produce_page_file;	  /* User VA. */
67 	u64 consume_page_file;	  /* User VA. */
68 	u64 produce_page_file_size;  /* Size of the file name array. */
69 	u64 consume_page_file_size;  /* Size of the file name array. */
70 	s32 result;
71 	u32 _pad;
72 };
73 
74 /* VMCISetNotifyInfo: Used to pass notify flag's address to the host driver. */
75 struct vmci_set_notify_info {
76 	u64 notify_uva;
77 	s32 result;
78 	u32 _pad;
79 };
80 
81 /*
82  * Per-instance host state
83  */
84 struct vmci_host_dev {
85 	struct vmci_ctx *context;
86 	int user_version;
87 	enum vmci_obj_type ct_type;
88 	struct mutex lock;  /* Mutex lock for vmci context access */
89 };
90 
91 static struct vmci_ctx *host_context;
92 static bool vmci_host_device_initialized;
93 static atomic_t vmci_host_active_users = ATOMIC_INIT(0);
94 
95 /*
96  * Determines whether the VMCI host personality is
97  * available. Since the core functionality of the host driver is
98  * always present, all guests could possibly use the host
99  * personality. However, to minimize the deviation from the
100  * pre-unified driver state of affairs, we only consider the host
101  * device active if there is no active guest device or if there
102  * are VMX'en with active VMCI contexts using the host device.
103  */
vmci_host_code_active(void)104 bool vmci_host_code_active(void)
105 {
106 	return vmci_host_device_initialized &&
107 	    (!vmci_guest_code_active() ||
108 	     atomic_read(&vmci_host_active_users) > 0);
109 }
110 
vmci_host_users(void)111 int vmci_host_users(void)
112 {
113 	return atomic_read(&vmci_host_active_users);
114 }
115 
116 /*
117  * Called on open of /dev/vmci.
118  */
vmci_host_open(struct inode * inode,struct file * filp)119 static int vmci_host_open(struct inode *inode, struct file *filp)
120 {
121 	struct vmci_host_dev *vmci_host_dev;
122 
123 	vmci_host_dev = kzalloc(sizeof(struct vmci_host_dev), GFP_KERNEL);
124 	if (vmci_host_dev == NULL)
125 		return -ENOMEM;
126 
127 	vmci_host_dev->ct_type = VMCIOBJ_NOT_SET;
128 	mutex_init(&vmci_host_dev->lock);
129 	filp->private_data = vmci_host_dev;
130 
131 	return 0;
132 }
133 
134 /*
135  * Called on close of /dev/vmci, most often when the process
136  * exits.
137  */
vmci_host_close(struct inode * inode,struct file * filp)138 static int vmci_host_close(struct inode *inode, struct file *filp)
139 {
140 	struct vmci_host_dev *vmci_host_dev = filp->private_data;
141 
142 	if (vmci_host_dev->ct_type == VMCIOBJ_CONTEXT) {
143 		vmci_ctx_destroy(vmci_host_dev->context);
144 		vmci_host_dev->context = NULL;
145 
146 		/*
147 		 * The number of active contexts is used to track whether any
148 		 * VMX'en are using the host personality. It is incremented when
149 		 * a context is created through the IOCTL_VMCI_INIT_CONTEXT
150 		 * ioctl.
151 		 */
152 		atomic_dec(&vmci_host_active_users);
153 	}
154 	vmci_host_dev->ct_type = VMCIOBJ_NOT_SET;
155 
156 	kfree(vmci_host_dev);
157 	filp->private_data = NULL;
158 	return 0;
159 }
160 
161 /*
162  * This is used to wake up the VMX when a VMCI call arrives, or
163  * to wake up select() or poll() at the next clock tick.
164  */
vmci_host_poll(struct file * filp,poll_table * wait)165 static __poll_t vmci_host_poll(struct file *filp, poll_table *wait)
166 {
167 	struct vmci_host_dev *vmci_host_dev = filp->private_data;
168 	struct vmci_ctx *context;
169 	__poll_t mask = 0;
170 
171 	if (vmci_host_dev->ct_type == VMCIOBJ_CONTEXT) {
172 		/*
173 		 * Read context only if ct_type == VMCIOBJ_CONTEXT to make
174 		 * sure that context is initialized
175 		 */
176 		context = vmci_host_dev->context;
177 
178 		/* Check for VMCI calls to this VM context. */
179 		if (wait)
180 			poll_wait(filp, &context->host_context.wait_queue,
181 				  wait);
182 
183 		spin_lock(&context->lock);
184 		if (context->pending_datagrams > 0 ||
185 		    vmci_handle_arr_get_size(
186 				context->pending_doorbell_array) > 0) {
187 			mask = EPOLLIN;
188 		}
189 		spin_unlock(&context->lock);
190 	}
191 	return mask;
192 }
193 
194 /*
195  * Copies the handles of a handle array into a user buffer, and
196  * returns the new length in userBufferSize. If the copy to the
197  * user buffer fails, the functions still returns VMCI_SUCCESS,
198  * but retval != 0.
199  */
drv_cp_harray_to_user(void __user * user_buf_uva,u64 * user_buf_size,struct vmci_handle_arr * handle_array,int * retval)200 static int drv_cp_harray_to_user(void __user *user_buf_uva,
201 				 u64 *user_buf_size,
202 				 struct vmci_handle_arr *handle_array,
203 				 int *retval)
204 {
205 	u32 array_size = 0;
206 	struct vmci_handle *handles;
207 
208 	if (handle_array)
209 		array_size = vmci_handle_arr_get_size(handle_array);
210 
211 	if (array_size * sizeof(*handles) > *user_buf_size)
212 		return VMCI_ERROR_MORE_DATA;
213 
214 	*user_buf_size = array_size * sizeof(*handles);
215 	if (*user_buf_size)
216 		*retval = copy_to_user(user_buf_uva,
217 				       vmci_handle_arr_get_handles
218 				       (handle_array), *user_buf_size);
219 
220 	return VMCI_SUCCESS;
221 }
222 
223 /*
224  * Sets up a given context for notify to work. Maps the notify
225  * boolean in user VA into kernel space.
226  */
vmci_host_setup_notify(struct vmci_ctx * context,unsigned long uva)227 static int vmci_host_setup_notify(struct vmci_ctx *context,
228 				  unsigned long uva)
229 {
230 	struct page *page;
231 	int retval;
232 
233 	if (context->notify_page) {
234 		pr_devel("%s: Notify mechanism is already set up\n", __func__);
235 		return VMCI_ERROR_DUPLICATE_ENTRY;
236 	}
237 
238 	/*
239 	 * We are using 'bool' internally, but let's make sure we explicit
240 	 * about the size.
241 	 */
242 	BUILD_BUG_ON(sizeof(bool) != sizeof(u8));
243 
244 	/*
245 	 * Lock physical page backing a given user VA.
246 	 */
247 	retval = get_user_pages_fast(uva, 1, FOLL_WRITE, &page);
248 	if (retval != 1)
249 		return VMCI_ERROR_GENERIC;
250 
251 	context->notify_page = page;
252 
253 	/*
254 	 * Map the locked page and set up notify pointer.
255 	 */
256 	context->notify = kmap(context->notify_page) + (uva & (PAGE_SIZE - 1));
257 	vmci_ctx_check_signal_notify(context);
258 
259 	return VMCI_SUCCESS;
260 }
261 
vmci_host_get_version(struct vmci_host_dev * vmci_host_dev,unsigned int cmd,void __user * uptr)262 static int vmci_host_get_version(struct vmci_host_dev *vmci_host_dev,
263 				 unsigned int cmd, void __user *uptr)
264 {
265 	if (cmd == IOCTL_VMCI_VERSION2) {
266 		int __user *vptr = uptr;
267 		if (get_user(vmci_host_dev->user_version, vptr))
268 			return -EFAULT;
269 	}
270 
271 	/*
272 	 * The basic logic here is:
273 	 *
274 	 * If the user sends in a version of 0 tell it our version.
275 	 * If the user didn't send in a version, tell it our version.
276 	 * If the user sent in an old version, tell it -its- version.
277 	 * If the user sent in an newer version, tell it our version.
278 	 *
279 	 * The rationale behind telling the caller its version is that
280 	 * Workstation 6.5 required that VMX and VMCI kernel module were
281 	 * version sync'd.  All new VMX users will be programmed to
282 	 * handle the VMCI kernel module version.
283 	 */
284 
285 	if (vmci_host_dev->user_version > 0 &&
286 	    vmci_host_dev->user_version < VMCI_VERSION_HOSTQP) {
287 		return vmci_host_dev->user_version;
288 	}
289 
290 	return VMCI_VERSION;
291 }
292 
293 #define vmci_ioctl_err(fmt, ...)	\
294 	pr_devel("%s: " fmt, ioctl_name, ##__VA_ARGS__)
295 
vmci_host_do_init_context(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)296 static int vmci_host_do_init_context(struct vmci_host_dev *vmci_host_dev,
297 				     const char *ioctl_name,
298 				     void __user *uptr)
299 {
300 	struct vmci_init_blk init_block;
301 	const struct cred *cred;
302 	int retval;
303 
304 	if (copy_from_user(&init_block, uptr, sizeof(init_block))) {
305 		vmci_ioctl_err("error reading init block\n");
306 		return -EFAULT;
307 	}
308 
309 	mutex_lock(&vmci_host_dev->lock);
310 
311 	if (vmci_host_dev->ct_type != VMCIOBJ_NOT_SET) {
312 		vmci_ioctl_err("received VMCI init on initialized handle\n");
313 		retval = -EINVAL;
314 		goto out;
315 	}
316 
317 	if (init_block.flags & ~VMCI_PRIVILEGE_FLAG_RESTRICTED) {
318 		vmci_ioctl_err("unsupported VMCI restriction flag\n");
319 		retval = -EINVAL;
320 		goto out;
321 	}
322 
323 	cred = get_current_cred();
324 	vmci_host_dev->context = vmci_ctx_create(init_block.cid,
325 						 init_block.flags, 0,
326 						 vmci_host_dev->user_version,
327 						 cred);
328 	put_cred(cred);
329 	if (IS_ERR(vmci_host_dev->context)) {
330 		retval = PTR_ERR(vmci_host_dev->context);
331 		vmci_ioctl_err("error initializing context\n");
332 		goto out;
333 	}
334 
335 	/*
336 	 * Copy cid to userlevel, we do this to allow the VMX
337 	 * to enforce its policy on cid generation.
338 	 */
339 	init_block.cid = vmci_ctx_get_id(vmci_host_dev->context);
340 	if (copy_to_user(uptr, &init_block, sizeof(init_block))) {
341 		vmci_ctx_destroy(vmci_host_dev->context);
342 		vmci_host_dev->context = NULL;
343 		vmci_ioctl_err("error writing init block\n");
344 		retval = -EFAULT;
345 		goto out;
346 	}
347 
348 	vmci_host_dev->ct_type = VMCIOBJ_CONTEXT;
349 	atomic_inc(&vmci_host_active_users);
350 
351 	vmci_call_vsock_callback(true);
352 
353 	retval = 0;
354 
355 out:
356 	mutex_unlock(&vmci_host_dev->lock);
357 	return retval;
358 }
359 
vmci_host_do_send_datagram(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)360 static int vmci_host_do_send_datagram(struct vmci_host_dev *vmci_host_dev,
361 				      const char *ioctl_name,
362 				      void __user *uptr)
363 {
364 	struct vmci_datagram_snd_rcv_info send_info;
365 	struct vmci_datagram *dg = NULL;
366 	u32 cid;
367 
368 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
369 		vmci_ioctl_err("only valid for contexts\n");
370 		return -EINVAL;
371 	}
372 
373 	if (copy_from_user(&send_info, uptr, sizeof(send_info)))
374 		return -EFAULT;
375 
376 	if (send_info.len > VMCI_MAX_DG_SIZE) {
377 		vmci_ioctl_err("datagram is too big (size=%d)\n",
378 			       send_info.len);
379 		return -EINVAL;
380 	}
381 
382 	if (send_info.len < sizeof(*dg)) {
383 		vmci_ioctl_err("datagram is too small (size=%d)\n",
384 			       send_info.len);
385 		return -EINVAL;
386 	}
387 
388 	dg = memdup_user((void __user *)(uintptr_t)send_info.addr,
389 			 send_info.len);
390 	if (IS_ERR(dg)) {
391 		vmci_ioctl_err(
392 			"cannot allocate memory to dispatch datagram\n");
393 		return PTR_ERR(dg);
394 	}
395 
396 	if (VMCI_DG_SIZE(dg) != send_info.len) {
397 		vmci_ioctl_err("datagram size mismatch\n");
398 		kfree(dg);
399 		return -EINVAL;
400 	}
401 
402 	pr_devel("Datagram dst (handle=0x%x:0x%x) src (handle=0x%x:0x%x), payload (size=%llu bytes)\n",
403 		 dg->dst.context, dg->dst.resource,
404 		 dg->src.context, dg->src.resource,
405 		 (unsigned long long)dg->payload_size);
406 
407 	/* Get source context id. */
408 	cid = vmci_ctx_get_id(vmci_host_dev->context);
409 	send_info.result = vmci_datagram_dispatch(cid, dg, true);
410 	kfree(dg);
411 
412 	return copy_to_user(uptr, &send_info, sizeof(send_info)) ? -EFAULT : 0;
413 }
414 
vmci_host_do_receive_datagram(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)415 static int vmci_host_do_receive_datagram(struct vmci_host_dev *vmci_host_dev,
416 					 const char *ioctl_name,
417 					 void __user *uptr)
418 {
419 	struct vmci_datagram_snd_rcv_info recv_info;
420 	struct vmci_datagram *dg = NULL;
421 	int retval;
422 	size_t size;
423 
424 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
425 		vmci_ioctl_err("only valid for contexts\n");
426 		return -EINVAL;
427 	}
428 
429 	if (copy_from_user(&recv_info, uptr, sizeof(recv_info)))
430 		return -EFAULT;
431 
432 	size = recv_info.len;
433 	recv_info.result = vmci_ctx_dequeue_datagram(vmci_host_dev->context,
434 						     &size, &dg);
435 
436 	if (recv_info.result >= VMCI_SUCCESS) {
437 		void __user *ubuf = (void __user *)(uintptr_t)recv_info.addr;
438 		retval = copy_to_user(ubuf, dg, VMCI_DG_SIZE(dg));
439 		kfree(dg);
440 		if (retval != 0)
441 			return -EFAULT;
442 	}
443 
444 	return copy_to_user(uptr, &recv_info, sizeof(recv_info)) ? -EFAULT : 0;
445 }
446 
vmci_host_do_alloc_queuepair(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)447 static int vmci_host_do_alloc_queuepair(struct vmci_host_dev *vmci_host_dev,
448 					const char *ioctl_name,
449 					void __user *uptr)
450 {
451 	struct vmci_handle handle;
452 	int vmci_status;
453 	int __user *retptr;
454 
455 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
456 		vmci_ioctl_err("only valid for contexts\n");
457 		return -EINVAL;
458 	}
459 
460 	if (vmci_host_dev->user_version < VMCI_VERSION_NOVMVM) {
461 		struct vmci_qp_alloc_info_vmvm alloc_info;
462 		struct vmci_qp_alloc_info_vmvm __user *info = uptr;
463 
464 		if (copy_from_user(&alloc_info, uptr, sizeof(alloc_info)))
465 			return -EFAULT;
466 
467 		handle = alloc_info.handle;
468 		retptr = &info->result;
469 
470 		vmci_status = vmci_qp_broker_alloc(alloc_info.handle,
471 						alloc_info.peer,
472 						alloc_info.flags,
473 						VMCI_NO_PRIVILEGE_FLAGS,
474 						alloc_info.produce_size,
475 						alloc_info.consume_size,
476 						NULL,
477 						vmci_host_dev->context);
478 
479 		if (vmci_status == VMCI_SUCCESS)
480 			vmci_status = VMCI_SUCCESS_QUEUEPAIR_CREATE;
481 	} else {
482 		struct vmci_qp_alloc_info alloc_info;
483 		struct vmci_qp_alloc_info __user *info = uptr;
484 		struct vmci_qp_page_store page_store;
485 
486 		if (copy_from_user(&alloc_info, uptr, sizeof(alloc_info)))
487 			return -EFAULT;
488 
489 		handle = alloc_info.handle;
490 		retptr = &info->result;
491 
492 		page_store.pages = alloc_info.ppn_va;
493 		page_store.len = alloc_info.num_ppns;
494 
495 		vmci_status = vmci_qp_broker_alloc(alloc_info.handle,
496 						alloc_info.peer,
497 						alloc_info.flags,
498 						VMCI_NO_PRIVILEGE_FLAGS,
499 						alloc_info.produce_size,
500 						alloc_info.consume_size,
501 						&page_store,
502 						vmci_host_dev->context);
503 	}
504 
505 	if (put_user(vmci_status, retptr)) {
506 		if (vmci_status >= VMCI_SUCCESS) {
507 			vmci_status = vmci_qp_broker_detach(handle,
508 							vmci_host_dev->context);
509 		}
510 		return -EFAULT;
511 	}
512 
513 	return 0;
514 }
515 
vmci_host_do_queuepair_setva(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)516 static int vmci_host_do_queuepair_setva(struct vmci_host_dev *vmci_host_dev,
517 					const char *ioctl_name,
518 					void __user *uptr)
519 {
520 	struct vmci_qp_set_va_info set_va_info;
521 	struct vmci_qp_set_va_info __user *info = uptr;
522 	s32 result;
523 
524 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
525 		vmci_ioctl_err("only valid for contexts\n");
526 		return -EINVAL;
527 	}
528 
529 	if (vmci_host_dev->user_version < VMCI_VERSION_NOVMVM) {
530 		vmci_ioctl_err("is not allowed\n");
531 		return -EINVAL;
532 	}
533 
534 	if (copy_from_user(&set_va_info, uptr, sizeof(set_va_info)))
535 		return -EFAULT;
536 
537 	if (set_va_info.va) {
538 		/*
539 		 * VMX is passing down a new VA for the queue
540 		 * pair mapping.
541 		 */
542 		result = vmci_qp_broker_map(set_va_info.handle,
543 					    vmci_host_dev->context,
544 					    set_va_info.va);
545 	} else {
546 		/*
547 		 * The queue pair is about to be unmapped by
548 		 * the VMX.
549 		 */
550 		result = vmci_qp_broker_unmap(set_va_info.handle,
551 					 vmci_host_dev->context, 0);
552 	}
553 
554 	return put_user(result, &info->result) ? -EFAULT : 0;
555 }
556 
vmci_host_do_queuepair_setpf(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)557 static int vmci_host_do_queuepair_setpf(struct vmci_host_dev *vmci_host_dev,
558 					const char *ioctl_name,
559 					void __user *uptr)
560 {
561 	struct vmci_qp_page_file_info page_file_info;
562 	struct vmci_qp_page_file_info __user *info = uptr;
563 	s32 result;
564 
565 	if (vmci_host_dev->user_version < VMCI_VERSION_HOSTQP ||
566 	    vmci_host_dev->user_version >= VMCI_VERSION_NOVMVM) {
567 		vmci_ioctl_err("not supported on this VMX (version=%d)\n",
568 			       vmci_host_dev->user_version);
569 		return -EINVAL;
570 	}
571 
572 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
573 		vmci_ioctl_err("only valid for contexts\n");
574 		return -EINVAL;
575 	}
576 
577 	if (copy_from_user(&page_file_info, uptr, sizeof(*info)))
578 		return -EFAULT;
579 
580 	/*
581 	 * Communicate success pre-emptively to the caller.  Note that the
582 	 * basic premise is that it is incumbent upon the caller not to look at
583 	 * the info.result field until after the ioctl() returns.  And then,
584 	 * only if the ioctl() result indicates no error.  We send up the
585 	 * SUCCESS status before calling SetPageStore() store because failing
586 	 * to copy up the result code means unwinding the SetPageStore().
587 	 *
588 	 * It turns out the logic to unwind a SetPageStore() opens a can of
589 	 * worms.  For example, if a host had created the queue_pair and a
590 	 * guest attaches and SetPageStore() is successful but writing success
591 	 * fails, then ... the host has to be stopped from writing (anymore)
592 	 * data into the queue_pair.  That means an additional test in the
593 	 * VMCI_Enqueue() code path.  Ugh.
594 	 */
595 
596 	if (put_user(VMCI_SUCCESS, &info->result)) {
597 		/*
598 		 * In this case, we can't write a result field of the
599 		 * caller's info block.  So, we don't even try to
600 		 * SetPageStore().
601 		 */
602 		return -EFAULT;
603 	}
604 
605 	result = vmci_qp_broker_set_page_store(page_file_info.handle,
606 						page_file_info.produce_va,
607 						page_file_info.consume_va,
608 						vmci_host_dev->context);
609 	if (result < VMCI_SUCCESS) {
610 		if (put_user(result, &info->result)) {
611 			/*
612 			 * Note that in this case the SetPageStore()
613 			 * call failed but we were unable to
614 			 * communicate that to the caller (because the
615 			 * copy_to_user() call failed).  So, if we
616 			 * simply return an error (in this case
617 			 * -EFAULT) then the caller will know that the
618 			 *  SetPageStore failed even though we couldn't
619 			 *  put the result code in the result field and
620 			 *  indicate exactly why it failed.
621 			 *
622 			 * That says nothing about the issue where we
623 			 * were once able to write to the caller's info
624 			 * memory and now can't.  Something more
625 			 * serious is probably going on than the fact
626 			 * that SetPageStore() didn't work.
627 			 */
628 			return -EFAULT;
629 		}
630 	}
631 
632 	return 0;
633 }
634 
vmci_host_do_qp_detach(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)635 static int vmci_host_do_qp_detach(struct vmci_host_dev *vmci_host_dev,
636 				  const char *ioctl_name,
637 				  void __user *uptr)
638 {
639 	struct vmci_qp_dtch_info detach_info;
640 	struct vmci_qp_dtch_info __user *info = uptr;
641 	s32 result;
642 
643 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
644 		vmci_ioctl_err("only valid for contexts\n");
645 		return -EINVAL;
646 	}
647 
648 	if (copy_from_user(&detach_info, uptr, sizeof(detach_info)))
649 		return -EFAULT;
650 
651 	result = vmci_qp_broker_detach(detach_info.handle,
652 				       vmci_host_dev->context);
653 	if (result == VMCI_SUCCESS &&
654 	    vmci_host_dev->user_version < VMCI_VERSION_NOVMVM) {
655 		result = VMCI_SUCCESS_LAST_DETACH;
656 	}
657 
658 	return put_user(result, &info->result) ? -EFAULT : 0;
659 }
660 
vmci_host_do_ctx_add_notify(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)661 static int vmci_host_do_ctx_add_notify(struct vmci_host_dev *vmci_host_dev,
662 				       const char *ioctl_name,
663 				       void __user *uptr)
664 {
665 	struct vmci_ctx_info ar_info;
666 	struct vmci_ctx_info __user *info = uptr;
667 	s32 result;
668 	u32 cid;
669 
670 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
671 		vmci_ioctl_err("only valid for contexts\n");
672 		return -EINVAL;
673 	}
674 
675 	if (copy_from_user(&ar_info, uptr, sizeof(ar_info)))
676 		return -EFAULT;
677 
678 	cid = vmci_ctx_get_id(vmci_host_dev->context);
679 	result = vmci_ctx_add_notification(cid, ar_info.remote_cid);
680 
681 	return put_user(result, &info->result) ? -EFAULT : 0;
682 }
683 
vmci_host_do_ctx_remove_notify(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)684 static int vmci_host_do_ctx_remove_notify(struct vmci_host_dev *vmci_host_dev,
685 					  const char *ioctl_name,
686 					  void __user *uptr)
687 {
688 	struct vmci_ctx_info ar_info;
689 	struct vmci_ctx_info __user *info = uptr;
690 	u32 cid;
691 	int result;
692 
693 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
694 		vmci_ioctl_err("only valid for contexts\n");
695 		return -EINVAL;
696 	}
697 
698 	if (copy_from_user(&ar_info, uptr, sizeof(ar_info)))
699 		return -EFAULT;
700 
701 	cid = vmci_ctx_get_id(vmci_host_dev->context);
702 	result = vmci_ctx_remove_notification(cid,
703 					      ar_info.remote_cid);
704 
705 	return put_user(result, &info->result) ? -EFAULT : 0;
706 }
707 
vmci_host_do_ctx_get_cpt_state(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)708 static int vmci_host_do_ctx_get_cpt_state(struct vmci_host_dev *vmci_host_dev,
709 					  const char *ioctl_name,
710 					  void __user *uptr)
711 {
712 	struct vmci_ctx_chkpt_buf_info get_info;
713 	u32 cid;
714 	void *cpt_buf;
715 	int retval;
716 
717 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
718 		vmci_ioctl_err("only valid for contexts\n");
719 		return -EINVAL;
720 	}
721 
722 	if (copy_from_user(&get_info, uptr, sizeof(get_info)))
723 		return -EFAULT;
724 
725 	cid = vmci_ctx_get_id(vmci_host_dev->context);
726 	get_info.result = vmci_ctx_get_chkpt_state(cid, get_info.cpt_type,
727 						&get_info.buf_size, &cpt_buf);
728 	if (get_info.result == VMCI_SUCCESS && get_info.buf_size) {
729 		void __user *ubuf = (void __user *)(uintptr_t)get_info.cpt_buf;
730 		retval = copy_to_user(ubuf, cpt_buf, get_info.buf_size);
731 		kfree(cpt_buf);
732 
733 		if (retval)
734 			return -EFAULT;
735 	}
736 
737 	return copy_to_user(uptr, &get_info, sizeof(get_info)) ? -EFAULT : 0;
738 }
739 
vmci_host_do_ctx_set_cpt_state(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)740 static int vmci_host_do_ctx_set_cpt_state(struct vmci_host_dev *vmci_host_dev,
741 					  const char *ioctl_name,
742 					  void __user *uptr)
743 {
744 	struct vmci_ctx_chkpt_buf_info set_info;
745 	u32 cid;
746 	void *cpt_buf;
747 	int retval;
748 
749 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
750 		vmci_ioctl_err("only valid for contexts\n");
751 		return -EINVAL;
752 	}
753 
754 	if (copy_from_user(&set_info, uptr, sizeof(set_info)))
755 		return -EFAULT;
756 
757 	cpt_buf = memdup_user((void __user *)(uintptr_t)set_info.cpt_buf,
758 				set_info.buf_size);
759 	if (IS_ERR(cpt_buf))
760 		return PTR_ERR(cpt_buf);
761 
762 	cid = vmci_ctx_get_id(vmci_host_dev->context);
763 	set_info.result = vmci_ctx_set_chkpt_state(cid, set_info.cpt_type,
764 						   set_info.buf_size, cpt_buf);
765 
766 	retval = copy_to_user(uptr, &set_info, sizeof(set_info)) ? -EFAULT : 0;
767 
768 	kfree(cpt_buf);
769 	return retval;
770 }
771 
vmci_host_do_get_context_id(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)772 static int vmci_host_do_get_context_id(struct vmci_host_dev *vmci_host_dev,
773 				       const char *ioctl_name,
774 				       void __user *uptr)
775 {
776 	u32 __user *u32ptr = uptr;
777 
778 	return put_user(VMCI_HOST_CONTEXT_ID, u32ptr) ? -EFAULT : 0;
779 }
780 
vmci_host_do_set_notify(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)781 static int vmci_host_do_set_notify(struct vmci_host_dev *vmci_host_dev,
782 				   const char *ioctl_name,
783 				   void __user *uptr)
784 {
785 	struct vmci_set_notify_info notify_info;
786 
787 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
788 		vmci_ioctl_err("only valid for contexts\n");
789 		return -EINVAL;
790 	}
791 
792 	if (copy_from_user(&notify_info, uptr, sizeof(notify_info)))
793 		return -EFAULT;
794 
795 	if (notify_info.notify_uva) {
796 		notify_info.result =
797 			vmci_host_setup_notify(vmci_host_dev->context,
798 					       notify_info.notify_uva);
799 	} else {
800 		vmci_ctx_unset_notify(vmci_host_dev->context);
801 		notify_info.result = VMCI_SUCCESS;
802 	}
803 
804 	return copy_to_user(uptr, &notify_info, sizeof(notify_info)) ?
805 		-EFAULT : 0;
806 }
807 
vmci_host_do_notify_resource(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)808 static int vmci_host_do_notify_resource(struct vmci_host_dev *vmci_host_dev,
809 					const char *ioctl_name,
810 					void __user *uptr)
811 {
812 	struct vmci_dbell_notify_resource_info info;
813 	u32 cid;
814 
815 	if (vmci_host_dev->user_version < VMCI_VERSION_NOTIFY) {
816 		vmci_ioctl_err("invalid for current VMX versions\n");
817 		return -EINVAL;
818 	}
819 
820 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
821 		vmci_ioctl_err("only valid for contexts\n");
822 		return -EINVAL;
823 	}
824 
825 	if (copy_from_user(&info, uptr, sizeof(info)))
826 		return -EFAULT;
827 
828 	cid = vmci_ctx_get_id(vmci_host_dev->context);
829 
830 	switch (info.action) {
831 	case VMCI_NOTIFY_RESOURCE_ACTION_NOTIFY:
832 		if (info.resource == VMCI_NOTIFY_RESOURCE_DOOR_BELL) {
833 			u32 flags = VMCI_NO_PRIVILEGE_FLAGS;
834 			info.result = vmci_ctx_notify_dbell(cid, info.handle,
835 							    flags);
836 		} else {
837 			info.result = VMCI_ERROR_UNAVAILABLE;
838 		}
839 		break;
840 
841 	case VMCI_NOTIFY_RESOURCE_ACTION_CREATE:
842 		info.result = vmci_ctx_dbell_create(cid, info.handle);
843 		break;
844 
845 	case VMCI_NOTIFY_RESOURCE_ACTION_DESTROY:
846 		info.result = vmci_ctx_dbell_destroy(cid, info.handle);
847 		break;
848 
849 	default:
850 		vmci_ioctl_err("got unknown action (action=%d)\n",
851 			       info.action);
852 		info.result = VMCI_ERROR_INVALID_ARGS;
853 	}
854 
855 	return copy_to_user(uptr, &info, sizeof(info)) ? -EFAULT : 0;
856 }
857 
vmci_host_do_recv_notifications(struct vmci_host_dev * vmci_host_dev,const char * ioctl_name,void __user * uptr)858 static int vmci_host_do_recv_notifications(struct vmci_host_dev *vmci_host_dev,
859 					   const char *ioctl_name,
860 					   void __user *uptr)
861 {
862 	struct vmci_ctx_notify_recv_info info;
863 	struct vmci_handle_arr *db_handle_array;
864 	struct vmci_handle_arr *qp_handle_array;
865 	void __user *ubuf;
866 	u32 cid;
867 	int retval = 0;
868 
869 	if (vmci_host_dev->ct_type != VMCIOBJ_CONTEXT) {
870 		vmci_ioctl_err("only valid for contexts\n");
871 		return -EINVAL;
872 	}
873 
874 	if (vmci_host_dev->user_version < VMCI_VERSION_NOTIFY) {
875 		vmci_ioctl_err("not supported for the current vmx version\n");
876 		return -EINVAL;
877 	}
878 
879 	if (copy_from_user(&info, uptr, sizeof(info)))
880 		return -EFAULT;
881 
882 	if ((info.db_handle_buf_size && !info.db_handle_buf_uva) ||
883 	    (info.qp_handle_buf_size && !info.qp_handle_buf_uva)) {
884 		return -EINVAL;
885 	}
886 
887 	cid = vmci_ctx_get_id(vmci_host_dev->context);
888 
889 	info.result = vmci_ctx_rcv_notifications_get(cid,
890 				&db_handle_array, &qp_handle_array);
891 	if (info.result != VMCI_SUCCESS)
892 		return copy_to_user(uptr, &info, sizeof(info)) ? -EFAULT : 0;
893 
894 	ubuf = (void __user *)(uintptr_t)info.db_handle_buf_uva;
895 	info.result = drv_cp_harray_to_user(ubuf, &info.db_handle_buf_size,
896 					    db_handle_array, &retval);
897 	if (info.result == VMCI_SUCCESS && !retval) {
898 		ubuf = (void __user *)(uintptr_t)info.qp_handle_buf_uva;
899 		info.result = drv_cp_harray_to_user(ubuf,
900 						    &info.qp_handle_buf_size,
901 						    qp_handle_array, &retval);
902 	}
903 
904 	if (!retval && copy_to_user(uptr, &info, sizeof(info)))
905 		retval = -EFAULT;
906 
907 	vmci_ctx_rcv_notifications_release(cid,
908 				db_handle_array, qp_handle_array,
909 				info.result == VMCI_SUCCESS && !retval);
910 
911 	return retval;
912 }
913 
vmci_host_unlocked_ioctl(struct file * filp,unsigned int iocmd,unsigned long ioarg)914 static long vmci_host_unlocked_ioctl(struct file *filp,
915 				     unsigned int iocmd, unsigned long ioarg)
916 {
917 #define VMCI_DO_IOCTL(ioctl_name, ioctl_fn) do {			\
918 		char *name = "IOCTL_VMCI_" # ioctl_name;		\
919 		return vmci_host_do_ ## ioctl_fn(			\
920 			vmci_host_dev, name, uptr);			\
921 	} while (0)
922 
923 	struct vmci_host_dev *vmci_host_dev = filp->private_data;
924 	void __user *uptr = (void __user *)ioarg;
925 
926 	switch (iocmd) {
927 	case IOCTL_VMCI_INIT_CONTEXT:
928 		VMCI_DO_IOCTL(INIT_CONTEXT, init_context);
929 	case IOCTL_VMCI_DATAGRAM_SEND:
930 		VMCI_DO_IOCTL(DATAGRAM_SEND, send_datagram);
931 	case IOCTL_VMCI_DATAGRAM_RECEIVE:
932 		VMCI_DO_IOCTL(DATAGRAM_RECEIVE, receive_datagram);
933 	case IOCTL_VMCI_QUEUEPAIR_ALLOC:
934 		VMCI_DO_IOCTL(QUEUEPAIR_ALLOC, alloc_queuepair);
935 	case IOCTL_VMCI_QUEUEPAIR_SETVA:
936 		VMCI_DO_IOCTL(QUEUEPAIR_SETVA, queuepair_setva);
937 	case IOCTL_VMCI_QUEUEPAIR_SETPAGEFILE:
938 		VMCI_DO_IOCTL(QUEUEPAIR_SETPAGEFILE, queuepair_setpf);
939 	case IOCTL_VMCI_QUEUEPAIR_DETACH:
940 		VMCI_DO_IOCTL(QUEUEPAIR_DETACH, qp_detach);
941 	case IOCTL_VMCI_CTX_ADD_NOTIFICATION:
942 		VMCI_DO_IOCTL(CTX_ADD_NOTIFICATION, ctx_add_notify);
943 	case IOCTL_VMCI_CTX_REMOVE_NOTIFICATION:
944 		VMCI_DO_IOCTL(CTX_REMOVE_NOTIFICATION, ctx_remove_notify);
945 	case IOCTL_VMCI_CTX_GET_CPT_STATE:
946 		VMCI_DO_IOCTL(CTX_GET_CPT_STATE, ctx_get_cpt_state);
947 	case IOCTL_VMCI_CTX_SET_CPT_STATE:
948 		VMCI_DO_IOCTL(CTX_SET_CPT_STATE, ctx_set_cpt_state);
949 	case IOCTL_VMCI_GET_CONTEXT_ID:
950 		VMCI_DO_IOCTL(GET_CONTEXT_ID, get_context_id);
951 	case IOCTL_VMCI_SET_NOTIFY:
952 		VMCI_DO_IOCTL(SET_NOTIFY, set_notify);
953 	case IOCTL_VMCI_NOTIFY_RESOURCE:
954 		VMCI_DO_IOCTL(NOTIFY_RESOURCE, notify_resource);
955 	case IOCTL_VMCI_NOTIFICATIONS_RECEIVE:
956 		VMCI_DO_IOCTL(NOTIFICATIONS_RECEIVE, recv_notifications);
957 
958 	case IOCTL_VMCI_VERSION:
959 	case IOCTL_VMCI_VERSION2:
960 		return vmci_host_get_version(vmci_host_dev, iocmd, uptr);
961 
962 	default:
963 		pr_devel("%s: Unknown ioctl (iocmd=%d)\n", __func__, iocmd);
964 		return -EINVAL;
965 	}
966 
967 #undef VMCI_DO_IOCTL
968 }
969 
970 static const struct file_operations vmuser_fops = {
971 	.owner		= THIS_MODULE,
972 	.open		= vmci_host_open,
973 	.release	= vmci_host_close,
974 	.poll		= vmci_host_poll,
975 	.unlocked_ioctl	= vmci_host_unlocked_ioctl,
976 	.compat_ioctl	= compat_ptr_ioctl,
977 };
978 
979 static struct miscdevice vmci_host_miscdev = {
980 	 .name = "vmci",
981 	 .minor = MISC_DYNAMIC_MINOR,
982 	 .fops = &vmuser_fops,
983 };
984 
vmci_host_init(void)985 int __init vmci_host_init(void)
986 {
987 	int error;
988 
989 	host_context = vmci_ctx_create(VMCI_HOST_CONTEXT_ID,
990 					VMCI_DEFAULT_PROC_PRIVILEGE_FLAGS,
991 					-1, VMCI_VERSION, NULL);
992 	if (IS_ERR(host_context)) {
993 		error = PTR_ERR(host_context);
994 		pr_warn("Failed to initialize VMCIContext (error%d)\n",
995 			error);
996 		return error;
997 	}
998 
999 	error = misc_register(&vmci_host_miscdev);
1000 	if (error) {
1001 		pr_warn("Module registration error (name=%s, major=%d, minor=%d, err=%d)\n",
1002 			vmci_host_miscdev.name,
1003 			MISC_MAJOR, vmci_host_miscdev.minor,
1004 			error);
1005 		pr_warn("Unable to initialize host personality\n");
1006 		vmci_ctx_destroy(host_context);
1007 		return error;
1008 	}
1009 
1010 	pr_info("VMCI host device registered (name=%s, major=%d, minor=%d)\n",
1011 		vmci_host_miscdev.name, MISC_MAJOR, vmci_host_miscdev.minor);
1012 
1013 	vmci_host_device_initialized = true;
1014 	return 0;
1015 }
1016 
vmci_host_exit(void)1017 void __exit vmci_host_exit(void)
1018 {
1019 	vmci_host_device_initialized = false;
1020 
1021 	misc_deregister(&vmci_host_miscdev);
1022 	vmci_ctx_destroy(host_context);
1023 	vmci_qp_broker_exit();
1024 
1025 	pr_debug("VMCI host driver module unloaded\n");
1026 }
1027