• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2006, Intel Corporation.
4  *
5  * Copyright (C) 2006-2008 Intel Corporation
6  * Author: Ashok Raj <ashok.raj@intel.com>
7  * Author: Shaohua Li <shaohua.li@intel.com>
8  * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9  *
10  * This file implements early detection/parsing of Remapping Devices
11  * reported to OS through BIOS via DMA remapping reporting (DMAR) ACPI
12  * tables.
13  *
14  * These routines are used by both DMA-remapping and Interrupt-remapping
15  */
16 
17 #define pr_fmt(fmt)     "DMAR: " fmt
18 
19 #include <linux/pci.h>
20 #include <linux/dmar.h>
21 #include <linux/iova.h>
22 #include <linux/intel-iommu.h>
23 #include <linux/timer.h>
24 #include <linux/irq.h>
25 #include <linux/interrupt.h>
26 #include <linux/tboot.h>
27 #include <linux/dmi.h>
28 #include <linux/slab.h>
29 #include <linux/iommu.h>
30 #include <linux/numa.h>
31 #include <linux/limits.h>
32 #include <asm/irq_remapping.h>
33 #include <asm/iommu_table.h>
34 
35 #include "../irq_remapping.h"
36 
37 typedef int (*dmar_res_handler_t)(struct acpi_dmar_header *, void *);
38 struct dmar_res_callback {
39 	dmar_res_handler_t	cb[ACPI_DMAR_TYPE_RESERVED];
40 	void			*arg[ACPI_DMAR_TYPE_RESERVED];
41 	bool			ignore_unhandled;
42 	bool			print_entry;
43 };
44 
45 /*
46  * Assumptions:
47  * 1) The hotplug framework guarentees that DMAR unit will be hot-added
48  *    before IO devices managed by that unit.
49  * 2) The hotplug framework guarantees that DMAR unit will be hot-removed
50  *    after IO devices managed by that unit.
51  * 3) Hotplug events are rare.
52  *
53  * Locking rules for DMA and interrupt remapping related global data structures:
54  * 1) Use dmar_global_lock in process context
55  * 2) Use RCU in interrupt context
56  */
57 DECLARE_RWSEM(dmar_global_lock);
58 LIST_HEAD(dmar_drhd_units);
59 
60 struct acpi_table_header * __initdata dmar_tbl;
61 static int dmar_dev_scope_status = 1;
62 static unsigned long dmar_seq_ids[BITS_TO_LONGS(DMAR_UNITS_SUPPORTED)];
63 
64 static int alloc_iommu(struct dmar_drhd_unit *drhd);
65 static void free_iommu(struct intel_iommu *iommu);
66 
67 extern const struct iommu_ops intel_iommu_ops;
68 
dmar_register_drhd_unit(struct dmar_drhd_unit * drhd)69 static void dmar_register_drhd_unit(struct dmar_drhd_unit *drhd)
70 {
71 	/*
72 	 * add INCLUDE_ALL at the tail, so scan the list will find it at
73 	 * the very end.
74 	 */
75 	if (drhd->include_all)
76 		list_add_tail_rcu(&drhd->list, &dmar_drhd_units);
77 	else
78 		list_add_rcu(&drhd->list, &dmar_drhd_units);
79 }
80 
dmar_alloc_dev_scope(void * start,void * end,int * cnt)81 void *dmar_alloc_dev_scope(void *start, void *end, int *cnt)
82 {
83 	struct acpi_dmar_device_scope *scope;
84 
85 	*cnt = 0;
86 	while (start < end) {
87 		scope = start;
88 		if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_NAMESPACE ||
89 		    scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
90 		    scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE)
91 			(*cnt)++;
92 		else if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_IOAPIC &&
93 			scope->entry_type != ACPI_DMAR_SCOPE_TYPE_HPET) {
94 			pr_warn("Unsupported device scope\n");
95 		}
96 		start += scope->length;
97 	}
98 	if (*cnt == 0)
99 		return NULL;
100 
101 	return kcalloc(*cnt, sizeof(struct dmar_dev_scope), GFP_KERNEL);
102 }
103 
dmar_free_dev_scope(struct dmar_dev_scope ** devices,int * cnt)104 void dmar_free_dev_scope(struct dmar_dev_scope **devices, int *cnt)
105 {
106 	int i;
107 	struct device *tmp_dev;
108 
109 	if (*devices && *cnt) {
110 		for_each_active_dev_scope(*devices, *cnt, i, tmp_dev)
111 			put_device(tmp_dev);
112 		kfree(*devices);
113 	}
114 
115 	*devices = NULL;
116 	*cnt = 0;
117 }
118 
119 /* Optimize out kzalloc()/kfree() for normal cases */
120 static char dmar_pci_notify_info_buf[64];
121 
122 static struct dmar_pci_notify_info *
dmar_alloc_pci_notify_info(struct pci_dev * dev,unsigned long event)123 dmar_alloc_pci_notify_info(struct pci_dev *dev, unsigned long event)
124 {
125 	int level = 0;
126 	size_t size;
127 	struct pci_dev *tmp;
128 	struct dmar_pci_notify_info *info;
129 
130 	BUG_ON(dev->is_virtfn);
131 
132 	/*
133 	 * Ignore devices that have a domain number higher than what can
134 	 * be looked up in DMAR, e.g. VMD subdevices with domain 0x10000
135 	 */
136 	if (pci_domain_nr(dev->bus) > U16_MAX)
137 		return NULL;
138 
139 	/* Only generate path[] for device addition event */
140 	if (event == BUS_NOTIFY_ADD_DEVICE)
141 		for (tmp = dev; tmp; tmp = tmp->bus->self)
142 			level++;
143 
144 	size = struct_size(info, path, level);
145 	if (size <= sizeof(dmar_pci_notify_info_buf)) {
146 		info = (struct dmar_pci_notify_info *)dmar_pci_notify_info_buf;
147 	} else {
148 		info = kzalloc(size, GFP_KERNEL);
149 		if (!info) {
150 			pr_warn("Out of memory when allocating notify_info "
151 				"for %s.\n", pci_name(dev));
152 			if (dmar_dev_scope_status == 0)
153 				dmar_dev_scope_status = -ENOMEM;
154 			return NULL;
155 		}
156 	}
157 
158 	info->event = event;
159 	info->dev = dev;
160 	info->seg = pci_domain_nr(dev->bus);
161 	info->level = level;
162 	if (event == BUS_NOTIFY_ADD_DEVICE) {
163 		for (tmp = dev; tmp; tmp = tmp->bus->self) {
164 			level--;
165 			info->path[level].bus = tmp->bus->number;
166 			info->path[level].device = PCI_SLOT(tmp->devfn);
167 			info->path[level].function = PCI_FUNC(tmp->devfn);
168 			if (pci_is_root_bus(tmp->bus))
169 				info->bus = tmp->bus->number;
170 		}
171 	}
172 
173 	return info;
174 }
175 
dmar_free_pci_notify_info(struct dmar_pci_notify_info * info)176 static inline void dmar_free_pci_notify_info(struct dmar_pci_notify_info *info)
177 {
178 	if ((void *)info != dmar_pci_notify_info_buf)
179 		kfree(info);
180 }
181 
dmar_match_pci_path(struct dmar_pci_notify_info * info,int bus,struct acpi_dmar_pci_path * path,int count)182 static bool dmar_match_pci_path(struct dmar_pci_notify_info *info, int bus,
183 				struct acpi_dmar_pci_path *path, int count)
184 {
185 	int i;
186 
187 	if (info->bus != bus)
188 		goto fallback;
189 	if (info->level != count)
190 		goto fallback;
191 
192 	for (i = 0; i < count; i++) {
193 		if (path[i].device != info->path[i].device ||
194 		    path[i].function != info->path[i].function)
195 			goto fallback;
196 	}
197 
198 	return true;
199 
200 fallback:
201 
202 	if (count != 1)
203 		return false;
204 
205 	i = info->level - 1;
206 	if (bus              == info->path[i].bus &&
207 	    path[0].device   == info->path[i].device &&
208 	    path[0].function == info->path[i].function) {
209 		pr_info(FW_BUG "RMRR entry for device %02x:%02x.%x is broken - applying workaround\n",
210 			bus, path[0].device, path[0].function);
211 		return true;
212 	}
213 
214 	return false;
215 }
216 
217 /* Return: > 0 if match found, 0 if no match found, < 0 if error happens */
dmar_insert_dev_scope(struct dmar_pci_notify_info * info,void * start,void * end,u16 segment,struct dmar_dev_scope * devices,int devices_cnt)218 int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
219 			  void *start, void*end, u16 segment,
220 			  struct dmar_dev_scope *devices,
221 			  int devices_cnt)
222 {
223 	int i, level;
224 	struct device *tmp, *dev = &info->dev->dev;
225 	struct acpi_dmar_device_scope *scope;
226 	struct acpi_dmar_pci_path *path;
227 
228 	if (segment != info->seg)
229 		return 0;
230 
231 	for (; start < end; start += scope->length) {
232 		scope = start;
233 		if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_ENDPOINT &&
234 		    scope->entry_type != ACPI_DMAR_SCOPE_TYPE_BRIDGE)
235 			continue;
236 
237 		path = (struct acpi_dmar_pci_path *)(scope + 1);
238 		level = (scope->length - sizeof(*scope)) / sizeof(*path);
239 		if (!dmar_match_pci_path(info, scope->bus, path, level))
240 			continue;
241 
242 		/*
243 		 * We expect devices with endpoint scope to have normal PCI
244 		 * headers, and devices with bridge scope to have bridge PCI
245 		 * headers.  However PCI NTB devices may be listed in the
246 		 * DMAR table with bridge scope, even though they have a
247 		 * normal PCI header.  NTB devices are identified by class
248 		 * "BRIDGE_OTHER" (0680h) - we don't declare a socpe mismatch
249 		 * for this special case.
250 		 */
251 		if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT &&
252 		     info->dev->hdr_type != PCI_HEADER_TYPE_NORMAL) ||
253 		    (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE &&
254 		     (info->dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
255 		      info->dev->class >> 16 != PCI_BASE_CLASS_BRIDGE))) {
256 			pr_warn("Device scope type does not match for %s\n",
257 				pci_name(info->dev));
258 			return -EINVAL;
259 		}
260 
261 		for_each_dev_scope(devices, devices_cnt, i, tmp)
262 			if (tmp == NULL) {
263 				devices[i].bus = info->dev->bus->number;
264 				devices[i].devfn = info->dev->devfn;
265 				rcu_assign_pointer(devices[i].dev,
266 						   get_device(dev));
267 				return 1;
268 			}
269 		BUG_ON(i >= devices_cnt);
270 	}
271 
272 	return 0;
273 }
274 
dmar_remove_dev_scope(struct dmar_pci_notify_info * info,u16 segment,struct dmar_dev_scope * devices,int count)275 int dmar_remove_dev_scope(struct dmar_pci_notify_info *info, u16 segment,
276 			  struct dmar_dev_scope *devices, int count)
277 {
278 	int index;
279 	struct device *tmp;
280 
281 	if (info->seg != segment)
282 		return 0;
283 
284 	for_each_active_dev_scope(devices, count, index, tmp)
285 		if (tmp == &info->dev->dev) {
286 			RCU_INIT_POINTER(devices[index].dev, NULL);
287 			synchronize_rcu();
288 			put_device(tmp);
289 			return 1;
290 		}
291 
292 	return 0;
293 }
294 
dmar_pci_bus_add_dev(struct dmar_pci_notify_info * info)295 static int dmar_pci_bus_add_dev(struct dmar_pci_notify_info *info)
296 {
297 	int ret = 0;
298 	struct dmar_drhd_unit *dmaru;
299 	struct acpi_dmar_hardware_unit *drhd;
300 
301 	for_each_drhd_unit(dmaru) {
302 		if (dmaru->include_all)
303 			continue;
304 
305 		drhd = container_of(dmaru->hdr,
306 				    struct acpi_dmar_hardware_unit, header);
307 		ret = dmar_insert_dev_scope(info, (void *)(drhd + 1),
308 				((void *)drhd) + drhd->header.length,
309 				dmaru->segment,
310 				dmaru->devices, dmaru->devices_cnt);
311 		if (ret)
312 			break;
313 	}
314 	if (ret >= 0)
315 		ret = dmar_iommu_notify_scope_dev(info);
316 	if (ret < 0 && dmar_dev_scope_status == 0)
317 		dmar_dev_scope_status = ret;
318 
319 	if (ret >= 0)
320 		intel_irq_remap_add_device(info);
321 
322 	return ret;
323 }
324 
dmar_pci_bus_del_dev(struct dmar_pci_notify_info * info)325 static void  dmar_pci_bus_del_dev(struct dmar_pci_notify_info *info)
326 {
327 	struct dmar_drhd_unit *dmaru;
328 
329 	for_each_drhd_unit(dmaru)
330 		if (dmar_remove_dev_scope(info, dmaru->segment,
331 			dmaru->devices, dmaru->devices_cnt))
332 			break;
333 	dmar_iommu_notify_scope_dev(info);
334 }
335 
vf_inherit_msi_domain(struct pci_dev * pdev)336 static inline void vf_inherit_msi_domain(struct pci_dev *pdev)
337 {
338 	struct pci_dev *physfn = pci_physfn(pdev);
339 
340 	dev_set_msi_domain(&pdev->dev, dev_get_msi_domain(&physfn->dev));
341 }
342 
dmar_pci_bus_notifier(struct notifier_block * nb,unsigned long action,void * data)343 static int dmar_pci_bus_notifier(struct notifier_block *nb,
344 				 unsigned long action, void *data)
345 {
346 	struct pci_dev *pdev = to_pci_dev(data);
347 	struct dmar_pci_notify_info *info;
348 
349 	/* Only care about add/remove events for physical functions.
350 	 * For VFs we actually do the lookup based on the corresponding
351 	 * PF in device_to_iommu() anyway. */
352 	if (pdev->is_virtfn) {
353 		/*
354 		 * Ensure that the VF device inherits the irq domain of the
355 		 * PF device. Ideally the device would inherit the domain
356 		 * from the bus, but DMAR can have multiple units per bus
357 		 * which makes this impossible. The VF 'bus' could inherit
358 		 * from the PF device, but that's yet another x86'sism to
359 		 * inflict on everybody else.
360 		 */
361 		if (action == BUS_NOTIFY_ADD_DEVICE)
362 			vf_inherit_msi_domain(pdev);
363 		return NOTIFY_DONE;
364 	}
365 
366 	if (action != BUS_NOTIFY_ADD_DEVICE &&
367 	    action != BUS_NOTIFY_REMOVED_DEVICE)
368 		return NOTIFY_DONE;
369 
370 	info = dmar_alloc_pci_notify_info(pdev, action);
371 	if (!info)
372 		return NOTIFY_DONE;
373 
374 	down_write(&dmar_global_lock);
375 	if (action == BUS_NOTIFY_ADD_DEVICE)
376 		dmar_pci_bus_add_dev(info);
377 	else if (action == BUS_NOTIFY_REMOVED_DEVICE)
378 		dmar_pci_bus_del_dev(info);
379 	up_write(&dmar_global_lock);
380 
381 	dmar_free_pci_notify_info(info);
382 
383 	return NOTIFY_OK;
384 }
385 
386 static struct notifier_block dmar_pci_bus_nb = {
387 	.notifier_call = dmar_pci_bus_notifier,
388 	.priority = INT_MIN,
389 };
390 
391 static struct dmar_drhd_unit *
dmar_find_dmaru(struct acpi_dmar_hardware_unit * drhd)392 dmar_find_dmaru(struct acpi_dmar_hardware_unit *drhd)
393 {
394 	struct dmar_drhd_unit *dmaru;
395 
396 	list_for_each_entry_rcu(dmaru, &dmar_drhd_units, list,
397 				dmar_rcu_check())
398 		if (dmaru->segment == drhd->segment &&
399 		    dmaru->reg_base_addr == drhd->address)
400 			return dmaru;
401 
402 	return NULL;
403 }
404 
405 /*
406  * dmar_parse_one_drhd - parses exactly one DMA remapping hardware definition
407  * structure which uniquely represent one DMA remapping hardware unit
408  * present in the platform
409  */
dmar_parse_one_drhd(struct acpi_dmar_header * header,void * arg)410 static int dmar_parse_one_drhd(struct acpi_dmar_header *header, void *arg)
411 {
412 	struct acpi_dmar_hardware_unit *drhd;
413 	struct dmar_drhd_unit *dmaru;
414 	int ret;
415 
416 	drhd = (struct acpi_dmar_hardware_unit *)header;
417 	dmaru = dmar_find_dmaru(drhd);
418 	if (dmaru)
419 		goto out;
420 
421 	dmaru = kzalloc(sizeof(*dmaru) + header->length, GFP_KERNEL);
422 	if (!dmaru)
423 		return -ENOMEM;
424 
425 	/*
426 	 * If header is allocated from slab by ACPI _DSM method, we need to
427 	 * copy the content because the memory buffer will be freed on return.
428 	 */
429 	dmaru->hdr = (void *)(dmaru + 1);
430 	memcpy(dmaru->hdr, header, header->length);
431 	dmaru->reg_base_addr = drhd->address;
432 	dmaru->segment = drhd->segment;
433 	dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
434 	dmaru->devices = dmar_alloc_dev_scope((void *)(drhd + 1),
435 					      ((void *)drhd) + drhd->header.length,
436 					      &dmaru->devices_cnt);
437 	if (dmaru->devices_cnt && dmaru->devices == NULL) {
438 		kfree(dmaru);
439 		return -ENOMEM;
440 	}
441 
442 	ret = alloc_iommu(dmaru);
443 	if (ret) {
444 		dmar_free_dev_scope(&dmaru->devices,
445 				    &dmaru->devices_cnt);
446 		kfree(dmaru);
447 		return ret;
448 	}
449 	dmar_register_drhd_unit(dmaru);
450 
451 out:
452 	if (arg)
453 		(*(int *)arg)++;
454 
455 	return 0;
456 }
457 
dmar_free_drhd(struct dmar_drhd_unit * dmaru)458 static void dmar_free_drhd(struct dmar_drhd_unit *dmaru)
459 {
460 	if (dmaru->devices && dmaru->devices_cnt)
461 		dmar_free_dev_scope(&dmaru->devices, &dmaru->devices_cnt);
462 	if (dmaru->iommu)
463 		free_iommu(dmaru->iommu);
464 	kfree(dmaru);
465 }
466 
dmar_parse_one_andd(struct acpi_dmar_header * header,void * arg)467 static int __init dmar_parse_one_andd(struct acpi_dmar_header *header,
468 				      void *arg)
469 {
470 	struct acpi_dmar_andd *andd = (void *)header;
471 
472 	/* Check for NUL termination within the designated length */
473 	if (strnlen(andd->device_name, header->length - 8) == header->length - 8) {
474 		pr_warn(FW_BUG
475 			   "Your BIOS is broken; ANDD object name is not NUL-terminated\n"
476 			   "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
477 			   dmi_get_system_info(DMI_BIOS_VENDOR),
478 			   dmi_get_system_info(DMI_BIOS_VERSION),
479 			   dmi_get_system_info(DMI_PRODUCT_VERSION));
480 		add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
481 		return -EINVAL;
482 	}
483 	pr_info("ANDD device: %x name: %s\n", andd->device_number,
484 		andd->device_name);
485 
486 	return 0;
487 }
488 
489 #ifdef CONFIG_ACPI_NUMA
dmar_parse_one_rhsa(struct acpi_dmar_header * header,void * arg)490 static int dmar_parse_one_rhsa(struct acpi_dmar_header *header, void *arg)
491 {
492 	struct acpi_dmar_rhsa *rhsa;
493 	struct dmar_drhd_unit *drhd;
494 
495 	rhsa = (struct acpi_dmar_rhsa *)header;
496 	for_each_drhd_unit(drhd) {
497 		if (drhd->reg_base_addr == rhsa->base_address) {
498 			int node = pxm_to_node(rhsa->proximity_domain);
499 
500 			if (!node_online(node))
501 				node = NUMA_NO_NODE;
502 			drhd->iommu->node = node;
503 			return 0;
504 		}
505 	}
506 	pr_warn(FW_BUG
507 		"Your BIOS is broken; RHSA refers to non-existent DMAR unit at %llx\n"
508 		"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
509 		rhsa->base_address,
510 		dmi_get_system_info(DMI_BIOS_VENDOR),
511 		dmi_get_system_info(DMI_BIOS_VERSION),
512 		dmi_get_system_info(DMI_PRODUCT_VERSION));
513 	add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
514 
515 	return 0;
516 }
517 #else
518 #define	dmar_parse_one_rhsa		dmar_res_noop
519 #endif
520 
521 static void
dmar_table_print_dmar_entry(struct acpi_dmar_header * header)522 dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
523 {
524 	struct acpi_dmar_hardware_unit *drhd;
525 	struct acpi_dmar_reserved_memory *rmrr;
526 	struct acpi_dmar_atsr *atsr;
527 	struct acpi_dmar_rhsa *rhsa;
528 
529 	switch (header->type) {
530 	case ACPI_DMAR_TYPE_HARDWARE_UNIT:
531 		drhd = container_of(header, struct acpi_dmar_hardware_unit,
532 				    header);
533 		pr_info("DRHD base: %#016Lx flags: %#x\n",
534 			(unsigned long long)drhd->address, drhd->flags);
535 		break;
536 	case ACPI_DMAR_TYPE_RESERVED_MEMORY:
537 		rmrr = container_of(header, struct acpi_dmar_reserved_memory,
538 				    header);
539 		pr_info("RMRR base: %#016Lx end: %#016Lx\n",
540 			(unsigned long long)rmrr->base_address,
541 			(unsigned long long)rmrr->end_address);
542 		break;
543 	case ACPI_DMAR_TYPE_ROOT_ATS:
544 		atsr = container_of(header, struct acpi_dmar_atsr, header);
545 		pr_info("ATSR flags: %#x\n", atsr->flags);
546 		break;
547 	case ACPI_DMAR_TYPE_HARDWARE_AFFINITY:
548 		rhsa = container_of(header, struct acpi_dmar_rhsa, header);
549 		pr_info("RHSA base: %#016Lx proximity domain: %#x\n",
550 		       (unsigned long long)rhsa->base_address,
551 		       rhsa->proximity_domain);
552 		break;
553 	case ACPI_DMAR_TYPE_NAMESPACE:
554 		/* We don't print this here because we need to sanity-check
555 		   it first. So print it in dmar_parse_one_andd() instead. */
556 		break;
557 	}
558 }
559 
560 /**
561  * dmar_table_detect - checks to see if the platform supports DMAR devices
562  */
dmar_table_detect(void)563 static int __init dmar_table_detect(void)
564 {
565 	acpi_status status = AE_OK;
566 
567 	/* if we could find DMAR table, then there are DMAR devices */
568 	status = acpi_get_table(ACPI_SIG_DMAR, 0, &dmar_tbl);
569 
570 	if (ACPI_SUCCESS(status) && !dmar_tbl) {
571 		pr_warn("Unable to map DMAR\n");
572 		status = AE_NOT_FOUND;
573 	}
574 
575 	return ACPI_SUCCESS(status) ? 0 : -ENOENT;
576 }
577 
dmar_walk_remapping_entries(struct acpi_dmar_header * start,size_t len,struct dmar_res_callback * cb)578 static int dmar_walk_remapping_entries(struct acpi_dmar_header *start,
579 				       size_t len, struct dmar_res_callback *cb)
580 {
581 	struct acpi_dmar_header *iter, *next;
582 	struct acpi_dmar_header *end = ((void *)start) + len;
583 
584 	for (iter = start; iter < end; iter = next) {
585 		next = (void *)iter + iter->length;
586 		if (iter->length == 0) {
587 			/* Avoid looping forever on bad ACPI tables */
588 			pr_debug(FW_BUG "Invalid 0-length structure\n");
589 			break;
590 		} else if (next > end) {
591 			/* Avoid passing table end */
592 			pr_warn(FW_BUG "Record passes table end\n");
593 			return -EINVAL;
594 		}
595 
596 		if (cb->print_entry)
597 			dmar_table_print_dmar_entry(iter);
598 
599 		if (iter->type >= ACPI_DMAR_TYPE_RESERVED) {
600 			/* continue for forward compatibility */
601 			pr_debug("Unknown DMAR structure type %d\n",
602 				 iter->type);
603 		} else if (cb->cb[iter->type]) {
604 			int ret;
605 
606 			ret = cb->cb[iter->type](iter, cb->arg[iter->type]);
607 			if (ret)
608 				return ret;
609 		} else if (!cb->ignore_unhandled) {
610 			pr_warn("No handler for DMAR structure type %d\n",
611 				iter->type);
612 			return -EINVAL;
613 		}
614 	}
615 
616 	return 0;
617 }
618 
dmar_walk_dmar_table(struct acpi_table_dmar * dmar,struct dmar_res_callback * cb)619 static inline int dmar_walk_dmar_table(struct acpi_table_dmar *dmar,
620 				       struct dmar_res_callback *cb)
621 {
622 	return dmar_walk_remapping_entries((void *)(dmar + 1),
623 			dmar->header.length - sizeof(*dmar), cb);
624 }
625 
626 /**
627  * parse_dmar_table - parses the DMA reporting table
628  */
629 static int __init
parse_dmar_table(void)630 parse_dmar_table(void)
631 {
632 	struct acpi_table_dmar *dmar;
633 	int drhd_count = 0;
634 	int ret;
635 	struct dmar_res_callback cb = {
636 		.print_entry = true,
637 		.ignore_unhandled = true,
638 		.arg[ACPI_DMAR_TYPE_HARDWARE_UNIT] = &drhd_count,
639 		.cb[ACPI_DMAR_TYPE_HARDWARE_UNIT] = &dmar_parse_one_drhd,
640 		.cb[ACPI_DMAR_TYPE_RESERVED_MEMORY] = &dmar_parse_one_rmrr,
641 		.cb[ACPI_DMAR_TYPE_ROOT_ATS] = &dmar_parse_one_atsr,
642 		.cb[ACPI_DMAR_TYPE_HARDWARE_AFFINITY] = &dmar_parse_one_rhsa,
643 		.cb[ACPI_DMAR_TYPE_NAMESPACE] = &dmar_parse_one_andd,
644 	};
645 
646 	/*
647 	 * Do it again, earlier dmar_tbl mapping could be mapped with
648 	 * fixed map.
649 	 */
650 	dmar_table_detect();
651 
652 	/*
653 	 * ACPI tables may not be DMA protected by tboot, so use DMAR copy
654 	 * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
655 	 */
656 	dmar_tbl = tboot_get_dmar_table(dmar_tbl);
657 
658 	dmar = (struct acpi_table_dmar *)dmar_tbl;
659 	if (!dmar)
660 		return -ENODEV;
661 
662 	if (dmar->width < PAGE_SHIFT - 1) {
663 		pr_warn("Invalid DMAR haw\n");
664 		return -EINVAL;
665 	}
666 
667 	pr_info("Host address width %d\n", dmar->width + 1);
668 	ret = dmar_walk_dmar_table(dmar, &cb);
669 	if (ret == 0 && drhd_count == 0)
670 		pr_warn(FW_BUG "No DRHD structure found in DMAR table\n");
671 
672 	return ret;
673 }
674 
dmar_pci_device_match(struct dmar_dev_scope devices[],int cnt,struct pci_dev * dev)675 static int dmar_pci_device_match(struct dmar_dev_scope devices[],
676 				 int cnt, struct pci_dev *dev)
677 {
678 	int index;
679 	struct device *tmp;
680 
681 	while (dev) {
682 		for_each_active_dev_scope(devices, cnt, index, tmp)
683 			if (dev_is_pci(tmp) && dev == to_pci_dev(tmp))
684 				return 1;
685 
686 		/* Check our parent */
687 		dev = dev->bus->self;
688 	}
689 
690 	return 0;
691 }
692 
693 struct dmar_drhd_unit *
dmar_find_matched_drhd_unit(struct pci_dev * dev)694 dmar_find_matched_drhd_unit(struct pci_dev *dev)
695 {
696 	struct dmar_drhd_unit *dmaru;
697 	struct acpi_dmar_hardware_unit *drhd;
698 
699 	dev = pci_physfn(dev);
700 
701 	rcu_read_lock();
702 	for_each_drhd_unit(dmaru) {
703 		drhd = container_of(dmaru->hdr,
704 				    struct acpi_dmar_hardware_unit,
705 				    header);
706 
707 		if (dmaru->include_all &&
708 		    drhd->segment == pci_domain_nr(dev->bus))
709 			goto out;
710 
711 		if (dmar_pci_device_match(dmaru->devices,
712 					  dmaru->devices_cnt, dev))
713 			goto out;
714 	}
715 	dmaru = NULL;
716 out:
717 	rcu_read_unlock();
718 
719 	return dmaru;
720 }
721 
dmar_acpi_insert_dev_scope(u8 device_number,struct acpi_device * adev)722 static void __init dmar_acpi_insert_dev_scope(u8 device_number,
723 					      struct acpi_device *adev)
724 {
725 	struct dmar_drhd_unit *dmaru;
726 	struct acpi_dmar_hardware_unit *drhd;
727 	struct acpi_dmar_device_scope *scope;
728 	struct device *tmp;
729 	int i;
730 	struct acpi_dmar_pci_path *path;
731 
732 	for_each_drhd_unit(dmaru) {
733 		drhd = container_of(dmaru->hdr,
734 				    struct acpi_dmar_hardware_unit,
735 				    header);
736 
737 		for (scope = (void *)(drhd + 1);
738 		     (unsigned long)scope < ((unsigned long)drhd) + drhd->header.length;
739 		     scope = ((void *)scope) + scope->length) {
740 			if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
741 				continue;
742 			if (scope->enumeration_id != device_number)
743 				continue;
744 
745 			path = (void *)(scope + 1);
746 			pr_info("ACPI device \"%s\" under DMAR at %llx as %02x:%02x.%d\n",
747 				dev_name(&adev->dev), dmaru->reg_base_addr,
748 				scope->bus, path->device, path->function);
749 			for_each_dev_scope(dmaru->devices, dmaru->devices_cnt, i, tmp)
750 				if (tmp == NULL) {
751 					dmaru->devices[i].bus = scope->bus;
752 					dmaru->devices[i].devfn = PCI_DEVFN(path->device,
753 									    path->function);
754 					rcu_assign_pointer(dmaru->devices[i].dev,
755 							   get_device(&adev->dev));
756 					return;
757 				}
758 			BUG_ON(i >= dmaru->devices_cnt);
759 		}
760 	}
761 	pr_warn("No IOMMU scope found for ANDD enumeration ID %d (%s)\n",
762 		device_number, dev_name(&adev->dev));
763 }
764 
dmar_acpi_dev_scope_init(void)765 static int __init dmar_acpi_dev_scope_init(void)
766 {
767 	struct acpi_dmar_andd *andd;
768 
769 	if (dmar_tbl == NULL)
770 		return -ENODEV;
771 
772 	for (andd = (void *)dmar_tbl + sizeof(struct acpi_table_dmar);
773 	     ((unsigned long)andd) < ((unsigned long)dmar_tbl) + dmar_tbl->length;
774 	     andd = ((void *)andd) + andd->header.length) {
775 		if (andd->header.type == ACPI_DMAR_TYPE_NAMESPACE) {
776 			acpi_handle h;
777 			struct acpi_device *adev;
778 
779 			if (!ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT,
780 							  andd->device_name,
781 							  &h))) {
782 				pr_err("Failed to find handle for ACPI object %s\n",
783 				       andd->device_name);
784 				continue;
785 			}
786 			if (acpi_bus_get_device(h, &adev)) {
787 				pr_err("Failed to get device for ACPI object %s\n",
788 				       andd->device_name);
789 				continue;
790 			}
791 			dmar_acpi_insert_dev_scope(andd->device_number, adev);
792 		}
793 	}
794 	return 0;
795 }
796 
dmar_dev_scope_init(void)797 int __init dmar_dev_scope_init(void)
798 {
799 	struct pci_dev *dev = NULL;
800 	struct dmar_pci_notify_info *info;
801 
802 	if (dmar_dev_scope_status != 1)
803 		return dmar_dev_scope_status;
804 
805 	if (list_empty(&dmar_drhd_units)) {
806 		dmar_dev_scope_status = -ENODEV;
807 	} else {
808 		dmar_dev_scope_status = 0;
809 
810 		dmar_acpi_dev_scope_init();
811 
812 		for_each_pci_dev(dev) {
813 			if (dev->is_virtfn)
814 				continue;
815 
816 			info = dmar_alloc_pci_notify_info(dev,
817 					BUS_NOTIFY_ADD_DEVICE);
818 			if (!info) {
819 				return dmar_dev_scope_status;
820 			} else {
821 				dmar_pci_bus_add_dev(info);
822 				dmar_free_pci_notify_info(info);
823 			}
824 		}
825 	}
826 
827 	return dmar_dev_scope_status;
828 }
829 
dmar_register_bus_notifier(void)830 void __init dmar_register_bus_notifier(void)
831 {
832 	bus_register_notifier(&pci_bus_type, &dmar_pci_bus_nb);
833 }
834 
835 
dmar_table_init(void)836 int __init dmar_table_init(void)
837 {
838 	static int dmar_table_initialized;
839 	int ret;
840 
841 	if (dmar_table_initialized == 0) {
842 		ret = parse_dmar_table();
843 		if (ret < 0) {
844 			if (ret != -ENODEV)
845 				pr_info("Parse DMAR table failure.\n");
846 		} else  if (list_empty(&dmar_drhd_units)) {
847 			pr_info("No DMAR devices found\n");
848 			ret = -ENODEV;
849 		}
850 
851 		if (ret < 0)
852 			dmar_table_initialized = ret;
853 		else
854 			dmar_table_initialized = 1;
855 	}
856 
857 	return dmar_table_initialized < 0 ? dmar_table_initialized : 0;
858 }
859 
warn_invalid_dmar(u64 addr,const char * message)860 static void warn_invalid_dmar(u64 addr, const char *message)
861 {
862 	pr_warn_once(FW_BUG
863 		"Your BIOS is broken; DMAR reported at address %llx%s!\n"
864 		"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
865 		addr, message,
866 		dmi_get_system_info(DMI_BIOS_VENDOR),
867 		dmi_get_system_info(DMI_BIOS_VERSION),
868 		dmi_get_system_info(DMI_PRODUCT_VERSION));
869 	add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
870 }
871 
872 static int __ref
dmar_validate_one_drhd(struct acpi_dmar_header * entry,void * arg)873 dmar_validate_one_drhd(struct acpi_dmar_header *entry, void *arg)
874 {
875 	struct acpi_dmar_hardware_unit *drhd;
876 	void __iomem *addr;
877 	u64 cap, ecap;
878 
879 	drhd = (void *)entry;
880 	if (!drhd->address) {
881 		warn_invalid_dmar(0, "");
882 		return -EINVAL;
883 	}
884 
885 	if (arg)
886 		addr = ioremap(drhd->address, VTD_PAGE_SIZE);
887 	else
888 		addr = early_ioremap(drhd->address, VTD_PAGE_SIZE);
889 	if (!addr) {
890 		pr_warn("Can't validate DRHD address: %llx\n", drhd->address);
891 		return -EINVAL;
892 	}
893 
894 	cap = dmar_readq(addr + DMAR_CAP_REG);
895 	ecap = dmar_readq(addr + DMAR_ECAP_REG);
896 
897 	if (arg)
898 		iounmap(addr);
899 	else
900 		early_iounmap(addr, VTD_PAGE_SIZE);
901 
902 	if (cap == (uint64_t)-1 && ecap == (uint64_t)-1) {
903 		warn_invalid_dmar(drhd->address, " returns all ones");
904 		return -EINVAL;
905 	}
906 
907 	return 0;
908 }
909 
detect_intel_iommu(void)910 int __init detect_intel_iommu(void)
911 {
912 	int ret;
913 	struct dmar_res_callback validate_drhd_cb = {
914 		.cb[ACPI_DMAR_TYPE_HARDWARE_UNIT] = &dmar_validate_one_drhd,
915 		.ignore_unhandled = true,
916 	};
917 
918 	down_write(&dmar_global_lock);
919 	ret = dmar_table_detect();
920 	if (!ret)
921 		ret = dmar_walk_dmar_table((struct acpi_table_dmar *)dmar_tbl,
922 					   &validate_drhd_cb);
923 	if (!ret && !no_iommu && !iommu_detected &&
924 	    (!dmar_disabled || dmar_platform_optin())) {
925 		iommu_detected = 1;
926 		/* Make sure ACS will be enabled */
927 		pci_request_acs();
928 	}
929 
930 #ifdef CONFIG_X86
931 	if (!ret) {
932 		x86_init.iommu.iommu_init = intel_iommu_init;
933 		x86_platform.iommu_shutdown = intel_iommu_shutdown;
934 	}
935 
936 #endif
937 
938 	if (dmar_tbl) {
939 		acpi_put_table(dmar_tbl);
940 		dmar_tbl = NULL;
941 	}
942 	up_write(&dmar_global_lock);
943 
944 	return ret ? ret : 1;
945 }
946 
unmap_iommu(struct intel_iommu * iommu)947 static void unmap_iommu(struct intel_iommu *iommu)
948 {
949 	iounmap(iommu->reg);
950 	release_mem_region(iommu->reg_phys, iommu->reg_size);
951 }
952 
953 /**
954  * map_iommu: map the iommu's registers
955  * @iommu: the iommu to map
956  * @phys_addr: the physical address of the base resgister
957  *
958  * Memory map the iommu's registers.  Start w/ a single page, and
959  * possibly expand if that turns out to be insufficent.
960  */
map_iommu(struct intel_iommu * iommu,u64 phys_addr)961 static int map_iommu(struct intel_iommu *iommu, u64 phys_addr)
962 {
963 	int map_size, err=0;
964 
965 	iommu->reg_phys = phys_addr;
966 	iommu->reg_size = VTD_PAGE_SIZE;
967 
968 	if (!request_mem_region(iommu->reg_phys, iommu->reg_size, iommu->name)) {
969 		pr_err("Can't reserve memory\n");
970 		err = -EBUSY;
971 		goto out;
972 	}
973 
974 	iommu->reg = ioremap(iommu->reg_phys, iommu->reg_size);
975 	if (!iommu->reg) {
976 		pr_err("Can't map the region\n");
977 		err = -ENOMEM;
978 		goto release;
979 	}
980 
981 	iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG);
982 	iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG);
983 
984 	if (iommu->cap == (uint64_t)-1 && iommu->ecap == (uint64_t)-1) {
985 		err = -EINVAL;
986 		warn_invalid_dmar(phys_addr, " returns all ones");
987 		goto unmap;
988 	}
989 	if (ecap_vcs(iommu->ecap))
990 		iommu->vccap = dmar_readq(iommu->reg + DMAR_VCCAP_REG);
991 
992 	/* the registers might be more than one page */
993 	map_size = max_t(int, ecap_max_iotlb_offset(iommu->ecap),
994 			 cap_max_fault_reg_offset(iommu->cap));
995 	map_size = VTD_PAGE_ALIGN(map_size);
996 	if (map_size > iommu->reg_size) {
997 		iounmap(iommu->reg);
998 		release_mem_region(iommu->reg_phys, iommu->reg_size);
999 		iommu->reg_size = map_size;
1000 		if (!request_mem_region(iommu->reg_phys, iommu->reg_size,
1001 					iommu->name)) {
1002 			pr_err("Can't reserve memory\n");
1003 			err = -EBUSY;
1004 			goto out;
1005 		}
1006 		iommu->reg = ioremap(iommu->reg_phys, iommu->reg_size);
1007 		if (!iommu->reg) {
1008 			pr_err("Can't map the region\n");
1009 			err = -ENOMEM;
1010 			goto release;
1011 		}
1012 	}
1013 	err = 0;
1014 	goto out;
1015 
1016 unmap:
1017 	iounmap(iommu->reg);
1018 release:
1019 	release_mem_region(iommu->reg_phys, iommu->reg_size);
1020 out:
1021 	return err;
1022 }
1023 
dmar_alloc_seq_id(struct intel_iommu * iommu)1024 static int dmar_alloc_seq_id(struct intel_iommu *iommu)
1025 {
1026 	iommu->seq_id = find_first_zero_bit(dmar_seq_ids,
1027 					    DMAR_UNITS_SUPPORTED);
1028 	if (iommu->seq_id >= DMAR_UNITS_SUPPORTED) {
1029 		iommu->seq_id = -1;
1030 	} else {
1031 		set_bit(iommu->seq_id, dmar_seq_ids);
1032 		sprintf(iommu->name, "dmar%d", iommu->seq_id);
1033 	}
1034 
1035 	return iommu->seq_id;
1036 }
1037 
dmar_free_seq_id(struct intel_iommu * iommu)1038 static void dmar_free_seq_id(struct intel_iommu *iommu)
1039 {
1040 	if (iommu->seq_id >= 0) {
1041 		clear_bit(iommu->seq_id, dmar_seq_ids);
1042 		iommu->seq_id = -1;
1043 	}
1044 }
1045 
alloc_iommu(struct dmar_drhd_unit * drhd)1046 static int alloc_iommu(struct dmar_drhd_unit *drhd)
1047 {
1048 	struct intel_iommu *iommu;
1049 	u32 ver, sts;
1050 	int agaw = -1;
1051 	int msagaw = -1;
1052 	int err;
1053 
1054 	if (!drhd->reg_base_addr) {
1055 		warn_invalid_dmar(0, "");
1056 		return -EINVAL;
1057 	}
1058 
1059 	iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
1060 	if (!iommu)
1061 		return -ENOMEM;
1062 
1063 	if (dmar_alloc_seq_id(iommu) < 0) {
1064 		pr_err("Failed to allocate seq_id\n");
1065 		err = -ENOSPC;
1066 		goto error;
1067 	}
1068 
1069 	err = map_iommu(iommu, drhd->reg_base_addr);
1070 	if (err) {
1071 		pr_err("Failed to map %s\n", iommu->name);
1072 		goto error_free_seq_id;
1073 	}
1074 
1075 	err = -EINVAL;
1076 	if (cap_sagaw(iommu->cap) == 0) {
1077 		pr_info("%s: No supported address widths. Not attempting DMA translation.\n",
1078 			iommu->name);
1079 		drhd->ignored = 1;
1080 	}
1081 
1082 	if (!drhd->ignored) {
1083 		agaw = iommu_calculate_agaw(iommu);
1084 		if (agaw < 0) {
1085 			pr_err("Cannot get a valid agaw for iommu (seq_id = %d)\n",
1086 			       iommu->seq_id);
1087 			drhd->ignored = 1;
1088 		}
1089 	}
1090 	if (!drhd->ignored) {
1091 		msagaw = iommu_calculate_max_sagaw(iommu);
1092 		if (msagaw < 0) {
1093 			pr_err("Cannot get a valid max agaw for iommu (seq_id = %d)\n",
1094 			       iommu->seq_id);
1095 			drhd->ignored = 1;
1096 			agaw = -1;
1097 		}
1098 	}
1099 	iommu->agaw = agaw;
1100 	iommu->msagaw = msagaw;
1101 	iommu->segment = drhd->segment;
1102 
1103 	iommu->node = NUMA_NO_NODE;
1104 
1105 	ver = readl(iommu->reg + DMAR_VER_REG);
1106 	pr_info("%s: reg_base_addr %llx ver %d:%d cap %llx ecap %llx\n",
1107 		iommu->name,
1108 		(unsigned long long)drhd->reg_base_addr,
1109 		DMAR_VER_MAJOR(ver), DMAR_VER_MINOR(ver),
1110 		(unsigned long long)iommu->cap,
1111 		(unsigned long long)iommu->ecap);
1112 
1113 	/* Reflect status in gcmd */
1114 	sts = readl(iommu->reg + DMAR_GSTS_REG);
1115 	if (sts & DMA_GSTS_IRES)
1116 		iommu->gcmd |= DMA_GCMD_IRE;
1117 	if (sts & DMA_GSTS_TES)
1118 		iommu->gcmd |= DMA_GCMD_TE;
1119 	if (sts & DMA_GSTS_QIES)
1120 		iommu->gcmd |= DMA_GCMD_QIE;
1121 
1122 	raw_spin_lock_init(&iommu->register_lock);
1123 
1124 	/*
1125 	 * This is only for hotplug; at boot time intel_iommu_enabled won't
1126 	 * be set yet. When intel_iommu_init() runs, it registers the units
1127 	 * present at boot time, then sets intel_iommu_enabled.
1128 	 */
1129 	if (intel_iommu_enabled && !drhd->ignored) {
1130 		err = iommu_device_sysfs_add(&iommu->iommu, NULL,
1131 					     intel_iommu_groups,
1132 					     "%s", iommu->name);
1133 		if (err)
1134 			goto err_unmap;
1135 
1136 		iommu_device_set_ops(&iommu->iommu, &intel_iommu_ops);
1137 
1138 		err = iommu_device_register(&iommu->iommu);
1139 		if (err)
1140 			goto err_sysfs;
1141 	}
1142 
1143 	drhd->iommu = iommu;
1144 	iommu->drhd = drhd;
1145 
1146 	return 0;
1147 
1148 err_sysfs:
1149 	iommu_device_sysfs_remove(&iommu->iommu);
1150 err_unmap:
1151 	unmap_iommu(iommu);
1152 error_free_seq_id:
1153 	dmar_free_seq_id(iommu);
1154 error:
1155 	kfree(iommu);
1156 	return err;
1157 }
1158 
free_iommu(struct intel_iommu * iommu)1159 static void free_iommu(struct intel_iommu *iommu)
1160 {
1161 	if (intel_iommu_enabled && !iommu->drhd->ignored) {
1162 		iommu_device_unregister(&iommu->iommu);
1163 		iommu_device_sysfs_remove(&iommu->iommu);
1164 	}
1165 
1166 	if (iommu->irq) {
1167 		if (iommu->pr_irq) {
1168 			free_irq(iommu->pr_irq, iommu);
1169 			dmar_free_hwirq(iommu->pr_irq);
1170 			iommu->pr_irq = 0;
1171 		}
1172 		free_irq(iommu->irq, iommu);
1173 		dmar_free_hwirq(iommu->irq);
1174 		iommu->irq = 0;
1175 	}
1176 
1177 	if (iommu->qi) {
1178 		free_page((unsigned long)iommu->qi->desc);
1179 		kfree(iommu->qi->desc_status);
1180 		kfree(iommu->qi);
1181 	}
1182 
1183 	if (iommu->reg)
1184 		unmap_iommu(iommu);
1185 
1186 	dmar_free_seq_id(iommu);
1187 	kfree(iommu);
1188 }
1189 
1190 /*
1191  * Reclaim all the submitted descriptors which have completed its work.
1192  */
reclaim_free_desc(struct q_inval * qi)1193 static inline void reclaim_free_desc(struct q_inval *qi)
1194 {
1195 	while (qi->desc_status[qi->free_tail] == QI_DONE ||
1196 	       qi->desc_status[qi->free_tail] == QI_ABORT) {
1197 		qi->desc_status[qi->free_tail] = QI_FREE;
1198 		qi->free_tail = (qi->free_tail + 1) % QI_LENGTH;
1199 		qi->free_cnt++;
1200 	}
1201 }
1202 
qi_check_fault(struct intel_iommu * iommu,int index,int wait_index)1203 static int qi_check_fault(struct intel_iommu *iommu, int index, int wait_index)
1204 {
1205 	u32 fault;
1206 	int head, tail;
1207 	struct q_inval *qi = iommu->qi;
1208 	int shift = qi_shift(iommu);
1209 
1210 	if (qi->desc_status[wait_index] == QI_ABORT)
1211 		return -EAGAIN;
1212 
1213 	fault = readl(iommu->reg + DMAR_FSTS_REG);
1214 
1215 	/*
1216 	 * If IQE happens, the head points to the descriptor associated
1217 	 * with the error. No new descriptors are fetched until the IQE
1218 	 * is cleared.
1219 	 */
1220 	if (fault & DMA_FSTS_IQE) {
1221 		head = readl(iommu->reg + DMAR_IQH_REG);
1222 		if ((head >> shift) == index) {
1223 			struct qi_desc *desc = qi->desc + head;
1224 
1225 			/*
1226 			 * desc->qw2 and desc->qw3 are either reserved or
1227 			 * used by software as private data. We won't print
1228 			 * out these two qw's for security consideration.
1229 			 */
1230 			pr_err("VT-d detected invalid descriptor: qw0 = %llx, qw1 = %llx\n",
1231 			       (unsigned long long)desc->qw0,
1232 			       (unsigned long long)desc->qw1);
1233 			memcpy(desc, qi->desc + (wait_index << shift),
1234 			       1 << shift);
1235 			writel(DMA_FSTS_IQE, iommu->reg + DMAR_FSTS_REG);
1236 			return -EINVAL;
1237 		}
1238 	}
1239 
1240 	/*
1241 	 * If ITE happens, all pending wait_desc commands are aborted.
1242 	 * No new descriptors are fetched until the ITE is cleared.
1243 	 */
1244 	if (fault & DMA_FSTS_ITE) {
1245 		head = readl(iommu->reg + DMAR_IQH_REG);
1246 		head = ((head >> shift) - 1 + QI_LENGTH) % QI_LENGTH;
1247 		head |= 1;
1248 		tail = readl(iommu->reg + DMAR_IQT_REG);
1249 		tail = ((tail >> shift) - 1 + QI_LENGTH) % QI_LENGTH;
1250 
1251 		writel(DMA_FSTS_ITE, iommu->reg + DMAR_FSTS_REG);
1252 
1253 		do {
1254 			if (qi->desc_status[head] == QI_IN_USE)
1255 				qi->desc_status[head] = QI_ABORT;
1256 			head = (head - 2 + QI_LENGTH) % QI_LENGTH;
1257 		} while (head != tail);
1258 
1259 		if (qi->desc_status[wait_index] == QI_ABORT)
1260 			return -EAGAIN;
1261 	}
1262 
1263 	if (fault & DMA_FSTS_ICE)
1264 		writel(DMA_FSTS_ICE, iommu->reg + DMAR_FSTS_REG);
1265 
1266 	return 0;
1267 }
1268 
1269 /*
1270  * Function to submit invalidation descriptors of all types to the queued
1271  * invalidation interface(QI). Multiple descriptors can be submitted at a
1272  * time, a wait descriptor will be appended to each submission to ensure
1273  * hardware has completed the invalidation before return. Wait descriptors
1274  * can be part of the submission but it will not be polled for completion.
1275  */
qi_submit_sync(struct intel_iommu * iommu,struct qi_desc * desc,unsigned int count,unsigned long options)1276 int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc,
1277 		   unsigned int count, unsigned long options)
1278 {
1279 	struct q_inval *qi = iommu->qi;
1280 	struct qi_desc wait_desc;
1281 	int wait_index, index;
1282 	unsigned long flags;
1283 	int offset, shift;
1284 	int rc, i;
1285 
1286 	if (!qi)
1287 		return 0;
1288 
1289 restart:
1290 	rc = 0;
1291 
1292 	raw_spin_lock_irqsave(&qi->q_lock, flags);
1293 	/*
1294 	 * Check if we have enough empty slots in the queue to submit,
1295 	 * the calculation is based on:
1296 	 * # of desc + 1 wait desc + 1 space between head and tail
1297 	 */
1298 	while (qi->free_cnt < count + 2) {
1299 		raw_spin_unlock_irqrestore(&qi->q_lock, flags);
1300 		cpu_relax();
1301 		raw_spin_lock_irqsave(&qi->q_lock, flags);
1302 	}
1303 
1304 	index = qi->free_head;
1305 	wait_index = (index + count) % QI_LENGTH;
1306 	shift = qi_shift(iommu);
1307 
1308 	for (i = 0; i < count; i++) {
1309 		offset = ((index + i) % QI_LENGTH) << shift;
1310 		memcpy(qi->desc + offset, &desc[i], 1 << shift);
1311 		qi->desc_status[(index + i) % QI_LENGTH] = QI_IN_USE;
1312 	}
1313 	qi->desc_status[wait_index] = QI_IN_USE;
1314 
1315 	wait_desc.qw0 = QI_IWD_STATUS_DATA(QI_DONE) |
1316 			QI_IWD_STATUS_WRITE | QI_IWD_TYPE;
1317 	if (options & QI_OPT_WAIT_DRAIN)
1318 		wait_desc.qw0 |= QI_IWD_PRQ_DRAIN;
1319 	wait_desc.qw1 = virt_to_phys(&qi->desc_status[wait_index]);
1320 	wait_desc.qw2 = 0;
1321 	wait_desc.qw3 = 0;
1322 
1323 	offset = wait_index << shift;
1324 	memcpy(qi->desc + offset, &wait_desc, 1 << shift);
1325 
1326 	qi->free_head = (qi->free_head + count + 1) % QI_LENGTH;
1327 	qi->free_cnt -= count + 1;
1328 
1329 	/*
1330 	 * update the HW tail register indicating the presence of
1331 	 * new descriptors.
1332 	 */
1333 	writel(qi->free_head << shift, iommu->reg + DMAR_IQT_REG);
1334 
1335 	while (qi->desc_status[wait_index] != QI_DONE) {
1336 		/*
1337 		 * We will leave the interrupts disabled, to prevent interrupt
1338 		 * context to queue another cmd while a cmd is already submitted
1339 		 * and waiting for completion on this cpu. This is to avoid
1340 		 * a deadlock where the interrupt context can wait indefinitely
1341 		 * for free slots in the queue.
1342 		 */
1343 		rc = qi_check_fault(iommu, index, wait_index);
1344 		if (rc)
1345 			break;
1346 
1347 		raw_spin_unlock(&qi->q_lock);
1348 		cpu_relax();
1349 		raw_spin_lock(&qi->q_lock);
1350 	}
1351 
1352 	for (i = 0; i < count; i++)
1353 		qi->desc_status[(index + i) % QI_LENGTH] = QI_DONE;
1354 
1355 	reclaim_free_desc(qi);
1356 	raw_spin_unlock_irqrestore(&qi->q_lock, flags);
1357 
1358 	if (rc == -EAGAIN)
1359 		goto restart;
1360 
1361 	return rc;
1362 }
1363 
1364 /*
1365  * Flush the global interrupt entry cache.
1366  */
qi_global_iec(struct intel_iommu * iommu)1367 void qi_global_iec(struct intel_iommu *iommu)
1368 {
1369 	struct qi_desc desc;
1370 
1371 	desc.qw0 = QI_IEC_TYPE;
1372 	desc.qw1 = 0;
1373 	desc.qw2 = 0;
1374 	desc.qw3 = 0;
1375 
1376 	/* should never fail */
1377 	qi_submit_sync(iommu, &desc, 1, 0);
1378 }
1379 
qi_flush_context(struct intel_iommu * iommu,u16 did,u16 sid,u8 fm,u64 type)1380 void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm,
1381 		      u64 type)
1382 {
1383 	struct qi_desc desc;
1384 
1385 	desc.qw0 = QI_CC_FM(fm) | QI_CC_SID(sid) | QI_CC_DID(did)
1386 			| QI_CC_GRAN(type) | QI_CC_TYPE;
1387 	desc.qw1 = 0;
1388 	desc.qw2 = 0;
1389 	desc.qw3 = 0;
1390 
1391 	qi_submit_sync(iommu, &desc, 1, 0);
1392 }
1393 
qi_flush_iotlb(struct intel_iommu * iommu,u16 did,u64 addr,unsigned int size_order,u64 type)1394 void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
1395 		    unsigned int size_order, u64 type)
1396 {
1397 	u8 dw = 0, dr = 0;
1398 
1399 	struct qi_desc desc;
1400 	int ih = 0;
1401 
1402 	if (cap_write_drain(iommu->cap))
1403 		dw = 1;
1404 
1405 	if (cap_read_drain(iommu->cap))
1406 		dr = 1;
1407 
1408 	desc.qw0 = QI_IOTLB_DID(did) | QI_IOTLB_DR(dr) | QI_IOTLB_DW(dw)
1409 		| QI_IOTLB_GRAN(type) | QI_IOTLB_TYPE;
1410 	desc.qw1 = QI_IOTLB_ADDR(addr) | QI_IOTLB_IH(ih)
1411 		| QI_IOTLB_AM(size_order);
1412 	desc.qw2 = 0;
1413 	desc.qw3 = 0;
1414 
1415 	qi_submit_sync(iommu, &desc, 1, 0);
1416 }
1417 
qi_flush_dev_iotlb(struct intel_iommu * iommu,u16 sid,u16 pfsid,u16 qdep,u64 addr,unsigned mask)1418 void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid,
1419 			u16 qdep, u64 addr, unsigned mask)
1420 {
1421 	struct qi_desc desc;
1422 
1423 	if (mask) {
1424 		addr |= (1ULL << (VTD_PAGE_SHIFT + mask - 1)) - 1;
1425 		desc.qw1 = QI_DEV_IOTLB_ADDR(addr) | QI_DEV_IOTLB_SIZE;
1426 	} else
1427 		desc.qw1 = QI_DEV_IOTLB_ADDR(addr);
1428 
1429 	if (qdep >= QI_DEV_IOTLB_MAX_INVS)
1430 		qdep = 0;
1431 
1432 	desc.qw0 = QI_DEV_IOTLB_SID(sid) | QI_DEV_IOTLB_QDEP(qdep) |
1433 		   QI_DIOTLB_TYPE | QI_DEV_IOTLB_PFSID(pfsid);
1434 	desc.qw2 = 0;
1435 	desc.qw3 = 0;
1436 
1437 	qi_submit_sync(iommu, &desc, 1, 0);
1438 }
1439 
1440 /* PASID-based IOTLB invalidation */
qi_flush_piotlb(struct intel_iommu * iommu,u16 did,u32 pasid,u64 addr,unsigned long npages,bool ih)1441 void qi_flush_piotlb(struct intel_iommu *iommu, u16 did, u32 pasid, u64 addr,
1442 		     unsigned long npages, bool ih)
1443 {
1444 	struct qi_desc desc = {.qw2 = 0, .qw3 = 0};
1445 
1446 	/*
1447 	 * npages == -1 means a PASID-selective invalidation, otherwise,
1448 	 * a positive value for Page-selective-within-PASID invalidation.
1449 	 * 0 is not a valid input.
1450 	 */
1451 	if (WARN_ON(!npages)) {
1452 		pr_err("Invalid input npages = %ld\n", npages);
1453 		return;
1454 	}
1455 
1456 	if (npages == -1) {
1457 		desc.qw0 = QI_EIOTLB_PASID(pasid) |
1458 				QI_EIOTLB_DID(did) |
1459 				QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) |
1460 				QI_EIOTLB_TYPE;
1461 		desc.qw1 = 0;
1462 	} else {
1463 		int mask = ilog2(__roundup_pow_of_two(npages));
1464 		unsigned long align = (1ULL << (VTD_PAGE_SHIFT + mask));
1465 
1466 		if (WARN_ON_ONCE(!IS_ALIGNED(addr, align)))
1467 			addr = ALIGN_DOWN(addr, align);
1468 
1469 		desc.qw0 = QI_EIOTLB_PASID(pasid) |
1470 				QI_EIOTLB_DID(did) |
1471 				QI_EIOTLB_GRAN(QI_GRAN_PSI_PASID) |
1472 				QI_EIOTLB_TYPE;
1473 		desc.qw1 = QI_EIOTLB_ADDR(addr) |
1474 				QI_EIOTLB_IH(ih) |
1475 				QI_EIOTLB_AM(mask);
1476 	}
1477 
1478 	qi_submit_sync(iommu, &desc, 1, 0);
1479 }
1480 
1481 /* PASID-based device IOTLB Invalidate */
qi_flush_dev_iotlb_pasid(struct intel_iommu * iommu,u16 sid,u16 pfsid,u32 pasid,u16 qdep,u64 addr,unsigned int size_order)1482 void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, u16 sid, u16 pfsid,
1483 			      u32 pasid,  u16 qdep, u64 addr, unsigned int size_order)
1484 {
1485 	unsigned long mask = 1UL << (VTD_PAGE_SHIFT + size_order - 1);
1486 	struct qi_desc desc = {.qw1 = 0, .qw2 = 0, .qw3 = 0};
1487 
1488 	desc.qw0 = QI_DEV_EIOTLB_PASID(pasid) | QI_DEV_EIOTLB_SID(sid) |
1489 		QI_DEV_EIOTLB_QDEP(qdep) | QI_DEIOTLB_TYPE |
1490 		QI_DEV_IOTLB_PFSID(pfsid);
1491 
1492 	/*
1493 	 * If S bit is 0, we only flush a single page. If S bit is set,
1494 	 * The least significant zero bit indicates the invalidation address
1495 	 * range. VT-d spec 6.5.2.6.
1496 	 * e.g. address bit 12[0] indicates 8KB, 13[0] indicates 16KB.
1497 	 * size order = 0 is PAGE_SIZE 4KB
1498 	 * Max Invs Pending (MIP) is set to 0 for now until we have DIT in
1499 	 * ECAP.
1500 	 */
1501 	if (!IS_ALIGNED(addr, VTD_PAGE_SIZE << size_order))
1502 		pr_warn_ratelimited("Invalidate non-aligned address %llx, order %d\n",
1503 				    addr, size_order);
1504 
1505 	/* Take page address */
1506 	desc.qw1 = QI_DEV_EIOTLB_ADDR(addr);
1507 
1508 	if (size_order) {
1509 		/*
1510 		 * Existing 0s in address below size_order may be the least
1511 		 * significant bit, we must set them to 1s to avoid having
1512 		 * smaller size than desired.
1513 		 */
1514 		desc.qw1 |= GENMASK_ULL(size_order + VTD_PAGE_SHIFT - 1,
1515 					VTD_PAGE_SHIFT);
1516 		/* Clear size_order bit to indicate size */
1517 		desc.qw1 &= ~mask;
1518 		/* Set the S bit to indicate flushing more than 1 page */
1519 		desc.qw1 |= QI_DEV_EIOTLB_SIZE;
1520 	}
1521 
1522 	qi_submit_sync(iommu, &desc, 1, 0);
1523 }
1524 
qi_flush_pasid_cache(struct intel_iommu * iommu,u16 did,u64 granu,u32 pasid)1525 void qi_flush_pasid_cache(struct intel_iommu *iommu, u16 did,
1526 			  u64 granu, u32 pasid)
1527 {
1528 	struct qi_desc desc = {.qw1 = 0, .qw2 = 0, .qw3 = 0};
1529 
1530 	desc.qw0 = QI_PC_PASID(pasid) | QI_PC_DID(did) |
1531 			QI_PC_GRAN(granu) | QI_PC_TYPE;
1532 	qi_submit_sync(iommu, &desc, 1, 0);
1533 }
1534 
1535 /*
1536  * Disable Queued Invalidation interface.
1537  */
dmar_disable_qi(struct intel_iommu * iommu)1538 void dmar_disable_qi(struct intel_iommu *iommu)
1539 {
1540 	unsigned long flags;
1541 	u32 sts;
1542 	cycles_t start_time = get_cycles();
1543 
1544 	if (!ecap_qis(iommu->ecap))
1545 		return;
1546 
1547 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
1548 
1549 	sts =  readl(iommu->reg + DMAR_GSTS_REG);
1550 	if (!(sts & DMA_GSTS_QIES))
1551 		goto end;
1552 
1553 	/*
1554 	 * Give a chance to HW to complete the pending invalidation requests.
1555 	 */
1556 	while ((readl(iommu->reg + DMAR_IQT_REG) !=
1557 		readl(iommu->reg + DMAR_IQH_REG)) &&
1558 		(DMAR_OPERATION_TIMEOUT > (get_cycles() - start_time)))
1559 		cpu_relax();
1560 
1561 	iommu->gcmd &= ~DMA_GCMD_QIE;
1562 	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
1563 
1564 	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl,
1565 		      !(sts & DMA_GSTS_QIES), sts);
1566 end:
1567 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
1568 }
1569 
1570 /*
1571  * Enable queued invalidation.
1572  */
__dmar_enable_qi(struct intel_iommu * iommu)1573 static void __dmar_enable_qi(struct intel_iommu *iommu)
1574 {
1575 	u32 sts;
1576 	unsigned long flags;
1577 	struct q_inval *qi = iommu->qi;
1578 	u64 val = virt_to_phys(qi->desc);
1579 
1580 	qi->free_head = qi->free_tail = 0;
1581 	qi->free_cnt = QI_LENGTH;
1582 
1583 	/*
1584 	 * Set DW=1 and QS=1 in IQA_REG when Scalable Mode capability
1585 	 * is present.
1586 	 */
1587 	if (ecap_smts(iommu->ecap))
1588 		val |= (1 << 11) | 1;
1589 
1590 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
1591 
1592 	/* write zero to the tail reg */
1593 	writel(0, iommu->reg + DMAR_IQT_REG);
1594 
1595 	dmar_writeq(iommu->reg + DMAR_IQA_REG, val);
1596 
1597 	iommu->gcmd |= DMA_GCMD_QIE;
1598 	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
1599 
1600 	/* Make sure hardware complete it */
1601 	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl, (sts & DMA_GSTS_QIES), sts);
1602 
1603 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
1604 }
1605 
1606 /*
1607  * Enable Queued Invalidation interface. This is a must to support
1608  * interrupt-remapping. Also used by DMA-remapping, which replaces
1609  * register based IOTLB invalidation.
1610  */
dmar_enable_qi(struct intel_iommu * iommu)1611 int dmar_enable_qi(struct intel_iommu *iommu)
1612 {
1613 	struct q_inval *qi;
1614 	struct page *desc_page;
1615 
1616 	if (!ecap_qis(iommu->ecap))
1617 		return -ENOENT;
1618 
1619 	/*
1620 	 * queued invalidation is already setup and enabled.
1621 	 */
1622 	if (iommu->qi)
1623 		return 0;
1624 
1625 	iommu->qi = kmalloc(sizeof(*qi), GFP_ATOMIC);
1626 	if (!iommu->qi)
1627 		return -ENOMEM;
1628 
1629 	qi = iommu->qi;
1630 
1631 	/*
1632 	 * Need two pages to accommodate 256 descriptors of 256 bits each
1633 	 * if the remapping hardware supports scalable mode translation.
1634 	 */
1635 	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
1636 				     !!ecap_smts(iommu->ecap));
1637 	if (!desc_page) {
1638 		kfree(qi);
1639 		iommu->qi = NULL;
1640 		return -ENOMEM;
1641 	}
1642 
1643 	qi->desc = page_address(desc_page);
1644 
1645 	qi->desc_status = kcalloc(QI_LENGTH, sizeof(int), GFP_ATOMIC);
1646 	if (!qi->desc_status) {
1647 		free_page((unsigned long) qi->desc);
1648 		kfree(qi);
1649 		iommu->qi = NULL;
1650 		return -ENOMEM;
1651 	}
1652 
1653 	raw_spin_lock_init(&qi->q_lock);
1654 
1655 	__dmar_enable_qi(iommu);
1656 
1657 	return 0;
1658 }
1659 
1660 /* iommu interrupt handling. Most stuff are MSI-like. */
1661 
1662 enum faulttype {
1663 	DMA_REMAP,
1664 	INTR_REMAP,
1665 	UNKNOWN,
1666 };
1667 
1668 static const char *dma_remap_fault_reasons[] =
1669 {
1670 	"Software",
1671 	"Present bit in root entry is clear",
1672 	"Present bit in context entry is clear",
1673 	"Invalid context entry",
1674 	"Access beyond MGAW",
1675 	"PTE Write access is not set",
1676 	"PTE Read access is not set",
1677 	"Next page table ptr is invalid",
1678 	"Root table address invalid",
1679 	"Context table ptr is invalid",
1680 	"non-zero reserved fields in RTP",
1681 	"non-zero reserved fields in CTP",
1682 	"non-zero reserved fields in PTE",
1683 	"PCE for translation request specifies blocking",
1684 };
1685 
1686 static const char * const dma_remap_sm_fault_reasons[] = {
1687 	"SM: Invalid Root Table Address",
1688 	"SM: TTM 0 for request with PASID",
1689 	"SM: TTM 0 for page group request",
1690 	"Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x33-0x37 */
1691 	"SM: Error attempting to access Root Entry",
1692 	"SM: Present bit in Root Entry is clear",
1693 	"SM: Non-zero reserved field set in Root Entry",
1694 	"Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x3B-0x3F */
1695 	"SM: Error attempting to access Context Entry",
1696 	"SM: Present bit in Context Entry is clear",
1697 	"SM: Non-zero reserved field set in the Context Entry",
1698 	"SM: Invalid Context Entry",
1699 	"SM: DTE field in Context Entry is clear",
1700 	"SM: PASID Enable field in Context Entry is clear",
1701 	"SM: PASID is larger than the max in Context Entry",
1702 	"SM: PRE field in Context-Entry is clear",
1703 	"SM: RID_PASID field error in Context-Entry",
1704 	"Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x49-0x4F */
1705 	"SM: Error attempting to access the PASID Directory Entry",
1706 	"SM: Present bit in Directory Entry is clear",
1707 	"SM: Non-zero reserved field set in PASID Directory Entry",
1708 	"Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x53-0x57 */
1709 	"SM: Error attempting to access PASID Table Entry",
1710 	"SM: Present bit in PASID Table Entry is clear",
1711 	"SM: Non-zero reserved field set in PASID Table Entry",
1712 	"SM: Invalid Scalable-Mode PASID Table Entry",
1713 	"SM: ERE field is clear in PASID Table Entry",
1714 	"SM: SRE field is clear in PASID Table Entry",
1715 	"Unknown", "Unknown",/* 0x5E-0x5F */
1716 	"Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x60-0x67 */
1717 	"Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x68-0x6F */
1718 	"SM: Error attempting to access first-level paging entry",
1719 	"SM: Present bit in first-level paging entry is clear",
1720 	"SM: Non-zero reserved field set in first-level paging entry",
1721 	"SM: Error attempting to access FL-PML4 entry",
1722 	"SM: First-level entry address beyond MGAW in Nested translation",
1723 	"SM: Read permission error in FL-PML4 entry in Nested translation",
1724 	"SM: Read permission error in first-level paging entry in Nested translation",
1725 	"SM: Write permission error in first-level paging entry in Nested translation",
1726 	"SM: Error attempting to access second-level paging entry",
1727 	"SM: Read/Write permission error in second-level paging entry",
1728 	"SM: Non-zero reserved field set in second-level paging entry",
1729 	"SM: Invalid second-level page table pointer",
1730 	"SM: A/D bit update needed in second-level entry when set up in no snoop",
1731 	"Unknown", "Unknown", "Unknown", /* 0x7D-0x7F */
1732 	"SM: Address in first-level translation is not canonical",
1733 	"SM: U/S set 0 for first-level translation with user privilege",
1734 	"SM: No execute permission for request with PASID and ER=1",
1735 	"SM: Address beyond the DMA hardware max",
1736 	"SM: Second-level entry address beyond the max",
1737 	"SM: No write permission for Write/AtomicOp request",
1738 	"SM: No read permission for Read/AtomicOp request",
1739 	"SM: Invalid address-interrupt address",
1740 	"Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x88-0x8F */
1741 	"SM: A/D bit update needed in first-level entry when set up in no snoop",
1742 };
1743 
1744 static const char *irq_remap_fault_reasons[] =
1745 {
1746 	"Detected reserved fields in the decoded interrupt-remapped request",
1747 	"Interrupt index exceeded the interrupt-remapping table size",
1748 	"Present field in the IRTE entry is clear",
1749 	"Error accessing interrupt-remapping table pointed by IRTA_REG",
1750 	"Detected reserved fields in the IRTE entry",
1751 	"Blocked a compatibility format interrupt request",
1752 	"Blocked an interrupt request due to source-id verification failure",
1753 };
1754 
dmar_get_fault_reason(u8 fault_reason,int * fault_type)1755 static const char *dmar_get_fault_reason(u8 fault_reason, int *fault_type)
1756 {
1757 	if (fault_reason >= 0x20 && (fault_reason - 0x20 <
1758 					ARRAY_SIZE(irq_remap_fault_reasons))) {
1759 		*fault_type = INTR_REMAP;
1760 		return irq_remap_fault_reasons[fault_reason - 0x20];
1761 	} else if (fault_reason >= 0x30 && (fault_reason - 0x30 <
1762 			ARRAY_SIZE(dma_remap_sm_fault_reasons))) {
1763 		*fault_type = DMA_REMAP;
1764 		return dma_remap_sm_fault_reasons[fault_reason - 0x30];
1765 	} else if (fault_reason < ARRAY_SIZE(dma_remap_fault_reasons)) {
1766 		*fault_type = DMA_REMAP;
1767 		return dma_remap_fault_reasons[fault_reason];
1768 	} else {
1769 		*fault_type = UNKNOWN;
1770 		return "Unknown";
1771 	}
1772 }
1773 
1774 
dmar_msi_reg(struct intel_iommu * iommu,int irq)1775 static inline int dmar_msi_reg(struct intel_iommu *iommu, int irq)
1776 {
1777 	if (iommu->irq == irq)
1778 		return DMAR_FECTL_REG;
1779 	else if (iommu->pr_irq == irq)
1780 		return DMAR_PECTL_REG;
1781 	else
1782 		BUG();
1783 }
1784 
dmar_msi_unmask(struct irq_data * data)1785 void dmar_msi_unmask(struct irq_data *data)
1786 {
1787 	struct intel_iommu *iommu = irq_data_get_irq_handler_data(data);
1788 	int reg = dmar_msi_reg(iommu, data->irq);
1789 	unsigned long flag;
1790 
1791 	/* unmask it */
1792 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
1793 	writel(0, iommu->reg + reg);
1794 	/* Read a reg to force flush the post write */
1795 	readl(iommu->reg + reg);
1796 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
1797 }
1798 
dmar_msi_mask(struct irq_data * data)1799 void dmar_msi_mask(struct irq_data *data)
1800 {
1801 	struct intel_iommu *iommu = irq_data_get_irq_handler_data(data);
1802 	int reg = dmar_msi_reg(iommu, data->irq);
1803 	unsigned long flag;
1804 
1805 	/* mask it */
1806 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
1807 	writel(DMA_FECTL_IM, iommu->reg + reg);
1808 	/* Read a reg to force flush the post write */
1809 	readl(iommu->reg + reg);
1810 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
1811 }
1812 
dmar_msi_write(int irq,struct msi_msg * msg)1813 void dmar_msi_write(int irq, struct msi_msg *msg)
1814 {
1815 	struct intel_iommu *iommu = irq_get_handler_data(irq);
1816 	int reg = dmar_msi_reg(iommu, irq);
1817 	unsigned long flag;
1818 
1819 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
1820 	writel(msg->data, iommu->reg + reg + 4);
1821 	writel(msg->address_lo, iommu->reg + reg + 8);
1822 	writel(msg->address_hi, iommu->reg + reg + 12);
1823 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
1824 }
1825 
dmar_msi_read(int irq,struct msi_msg * msg)1826 void dmar_msi_read(int irq, struct msi_msg *msg)
1827 {
1828 	struct intel_iommu *iommu = irq_get_handler_data(irq);
1829 	int reg = dmar_msi_reg(iommu, irq);
1830 	unsigned long flag;
1831 
1832 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
1833 	msg->data = readl(iommu->reg + reg + 4);
1834 	msg->address_lo = readl(iommu->reg + reg + 8);
1835 	msg->address_hi = readl(iommu->reg + reg + 12);
1836 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
1837 }
1838 
dmar_fault_do_one(struct intel_iommu * iommu,int type,u8 fault_reason,u32 pasid,u16 source_id,unsigned long long addr)1839 static int dmar_fault_do_one(struct intel_iommu *iommu, int type,
1840 		u8 fault_reason, u32 pasid, u16 source_id,
1841 		unsigned long long addr)
1842 {
1843 	const char *reason;
1844 	int fault_type;
1845 
1846 	reason = dmar_get_fault_reason(fault_reason, &fault_type);
1847 
1848 	if (fault_type == INTR_REMAP)
1849 		pr_err("[INTR-REMAP] Request device [%02x:%02x.%d] fault index %llx [fault reason %02d] %s\n",
1850 			source_id >> 8, PCI_SLOT(source_id & 0xFF),
1851 			PCI_FUNC(source_id & 0xFF), addr >> 48,
1852 			fault_reason, reason);
1853 	else
1854 		pr_err("[%s] Request device [%02x:%02x.%d] PASID %x fault addr %llx [fault reason %02d] %s\n",
1855 		       type ? "DMA Read" : "DMA Write",
1856 		       source_id >> 8, PCI_SLOT(source_id & 0xFF),
1857 		       PCI_FUNC(source_id & 0xFF), pasid, addr,
1858 		       fault_reason, reason);
1859 	return 0;
1860 }
1861 
1862 #define PRIMARY_FAULT_REG_LEN (16)
dmar_fault(int irq,void * dev_id)1863 irqreturn_t dmar_fault(int irq, void *dev_id)
1864 {
1865 	struct intel_iommu *iommu = dev_id;
1866 	int reg, fault_index;
1867 	u32 fault_status;
1868 	unsigned long flag;
1869 	static DEFINE_RATELIMIT_STATE(rs,
1870 				      DEFAULT_RATELIMIT_INTERVAL,
1871 				      DEFAULT_RATELIMIT_BURST);
1872 
1873 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
1874 	fault_status = readl(iommu->reg + DMAR_FSTS_REG);
1875 	if (fault_status && __ratelimit(&rs))
1876 		pr_err("DRHD: handling fault status reg %x\n", fault_status);
1877 
1878 	/* TBD: ignore advanced fault log currently */
1879 	if (!(fault_status & DMA_FSTS_PPF))
1880 		goto unlock_exit;
1881 
1882 	fault_index = dma_fsts_fault_record_index(fault_status);
1883 	reg = cap_fault_reg_offset(iommu->cap);
1884 	while (1) {
1885 		/* Disable printing, simply clear the fault when ratelimited */
1886 		bool ratelimited = !__ratelimit(&rs);
1887 		u8 fault_reason;
1888 		u16 source_id;
1889 		u64 guest_addr;
1890 		u32 pasid;
1891 		int type;
1892 		u32 data;
1893 		bool pasid_present;
1894 
1895 		/* highest 32 bits */
1896 		data = readl(iommu->reg + reg +
1897 				fault_index * PRIMARY_FAULT_REG_LEN + 12);
1898 		if (!(data & DMA_FRCD_F))
1899 			break;
1900 
1901 		if (!ratelimited) {
1902 			fault_reason = dma_frcd_fault_reason(data);
1903 			type = dma_frcd_type(data);
1904 
1905 			pasid = dma_frcd_pasid_value(data);
1906 			data = readl(iommu->reg + reg +
1907 				     fault_index * PRIMARY_FAULT_REG_LEN + 8);
1908 			source_id = dma_frcd_source_id(data);
1909 
1910 			pasid_present = dma_frcd_pasid_present(data);
1911 			guest_addr = dmar_readq(iommu->reg + reg +
1912 					fault_index * PRIMARY_FAULT_REG_LEN);
1913 			guest_addr = dma_frcd_page_addr(guest_addr);
1914 		}
1915 
1916 		/* clear the fault */
1917 		writel(DMA_FRCD_F, iommu->reg + reg +
1918 			fault_index * PRIMARY_FAULT_REG_LEN + 12);
1919 
1920 		raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
1921 
1922 		if (!ratelimited)
1923 			/* Using pasid -1 if pasid is not present */
1924 			dmar_fault_do_one(iommu, type, fault_reason,
1925 					  pasid_present ? pasid : -1,
1926 					  source_id, guest_addr);
1927 
1928 		fault_index++;
1929 		if (fault_index >= cap_num_fault_regs(iommu->cap))
1930 			fault_index = 0;
1931 		raw_spin_lock_irqsave(&iommu->register_lock, flag);
1932 	}
1933 
1934 	writel(DMA_FSTS_PFO | DMA_FSTS_PPF | DMA_FSTS_PRO,
1935 	       iommu->reg + DMAR_FSTS_REG);
1936 
1937 unlock_exit:
1938 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
1939 	return IRQ_HANDLED;
1940 }
1941 
dmar_set_interrupt(struct intel_iommu * iommu)1942 int dmar_set_interrupt(struct intel_iommu *iommu)
1943 {
1944 	int irq, ret;
1945 
1946 	/*
1947 	 * Check if the fault interrupt is already initialized.
1948 	 */
1949 	if (iommu->irq)
1950 		return 0;
1951 
1952 	irq = dmar_alloc_hwirq(iommu->seq_id, iommu->node, iommu);
1953 	if (irq > 0) {
1954 		iommu->irq = irq;
1955 	} else {
1956 		pr_err("No free IRQ vectors\n");
1957 		return -EINVAL;
1958 	}
1959 
1960 	ret = request_irq(irq, dmar_fault, IRQF_NO_THREAD, iommu->name, iommu);
1961 	if (ret)
1962 		pr_err("Can't request irq\n");
1963 	return ret;
1964 }
1965 
enable_drhd_fault_handling(void)1966 int __init enable_drhd_fault_handling(void)
1967 {
1968 	struct dmar_drhd_unit *drhd;
1969 	struct intel_iommu *iommu;
1970 
1971 	/*
1972 	 * Enable fault control interrupt.
1973 	 */
1974 	for_each_iommu(iommu, drhd) {
1975 		u32 fault_status;
1976 		int ret = dmar_set_interrupt(iommu);
1977 
1978 		if (ret) {
1979 			pr_err("DRHD %Lx: failed to enable fault, interrupt, ret %d\n",
1980 			       (unsigned long long)drhd->reg_base_addr, ret);
1981 			return -1;
1982 		}
1983 
1984 		/*
1985 		 * Clear any previous faults.
1986 		 */
1987 		dmar_fault(iommu->irq, iommu);
1988 		fault_status = readl(iommu->reg + DMAR_FSTS_REG);
1989 		writel(fault_status, iommu->reg + DMAR_FSTS_REG);
1990 	}
1991 
1992 	return 0;
1993 }
1994 
1995 /*
1996  * Re-enable Queued Invalidation interface.
1997  */
dmar_reenable_qi(struct intel_iommu * iommu)1998 int dmar_reenable_qi(struct intel_iommu *iommu)
1999 {
2000 	if (!ecap_qis(iommu->ecap))
2001 		return -ENOENT;
2002 
2003 	if (!iommu->qi)
2004 		return -ENOENT;
2005 
2006 	/*
2007 	 * First disable queued invalidation.
2008 	 */
2009 	dmar_disable_qi(iommu);
2010 	/*
2011 	 * Then enable queued invalidation again. Since there is no pending
2012 	 * invalidation requests now, it's safe to re-enable queued
2013 	 * invalidation.
2014 	 */
2015 	__dmar_enable_qi(iommu);
2016 
2017 	return 0;
2018 }
2019 
2020 /*
2021  * Check interrupt remapping support in DMAR table description.
2022  */
dmar_ir_support(void)2023 int __init dmar_ir_support(void)
2024 {
2025 	struct acpi_table_dmar *dmar;
2026 	dmar = (struct acpi_table_dmar *)dmar_tbl;
2027 	if (!dmar)
2028 		return 0;
2029 	return dmar->flags & 0x1;
2030 }
2031 
2032 /* Check whether DMAR units are in use */
dmar_in_use(void)2033 static inline bool dmar_in_use(void)
2034 {
2035 	return irq_remapping_enabled || intel_iommu_enabled;
2036 }
2037 
dmar_free_unused_resources(void)2038 static int __init dmar_free_unused_resources(void)
2039 {
2040 	struct dmar_drhd_unit *dmaru, *dmaru_n;
2041 
2042 	if (dmar_in_use())
2043 		return 0;
2044 
2045 	if (dmar_dev_scope_status != 1 && !list_empty(&dmar_drhd_units))
2046 		bus_unregister_notifier(&pci_bus_type, &dmar_pci_bus_nb);
2047 
2048 	down_write(&dmar_global_lock);
2049 	list_for_each_entry_safe(dmaru, dmaru_n, &dmar_drhd_units, list) {
2050 		list_del(&dmaru->list);
2051 		dmar_free_drhd(dmaru);
2052 	}
2053 	up_write(&dmar_global_lock);
2054 
2055 	return 0;
2056 }
2057 
2058 late_initcall(dmar_free_unused_resources);
2059 IOMMU_INIT_POST(detect_intel_iommu);
2060 
2061 /*
2062  * DMAR Hotplug Support
2063  * For more details, please refer to Intel(R) Virtualization Technology
2064  * for Directed-IO Architecture Specifiction, Rev 2.2, Section 8.8
2065  * "Remapping Hardware Unit Hot Plug".
2066  */
2067 static guid_t dmar_hp_guid =
2068 	GUID_INIT(0xD8C1A3A6, 0xBE9B, 0x4C9B,
2069 		  0x91, 0xBF, 0xC3, 0xCB, 0x81, 0xFC, 0x5D, 0xAF);
2070 
2071 /*
2072  * Currently there's only one revision and BIOS will not check the revision id,
2073  * so use 0 for safety.
2074  */
2075 #define	DMAR_DSM_REV_ID			0
2076 #define	DMAR_DSM_FUNC_DRHD		1
2077 #define	DMAR_DSM_FUNC_ATSR		2
2078 #define	DMAR_DSM_FUNC_RHSA		3
2079 
dmar_detect_dsm(acpi_handle handle,int func)2080 static inline bool dmar_detect_dsm(acpi_handle handle, int func)
2081 {
2082 	return acpi_check_dsm(handle, &dmar_hp_guid, DMAR_DSM_REV_ID, 1 << func);
2083 }
2084 
dmar_walk_dsm_resource(acpi_handle handle,int func,dmar_res_handler_t handler,void * arg)2085 static int dmar_walk_dsm_resource(acpi_handle handle, int func,
2086 				  dmar_res_handler_t handler, void *arg)
2087 {
2088 	int ret = -ENODEV;
2089 	union acpi_object *obj;
2090 	struct acpi_dmar_header *start;
2091 	struct dmar_res_callback callback;
2092 	static int res_type[] = {
2093 		[DMAR_DSM_FUNC_DRHD] = ACPI_DMAR_TYPE_HARDWARE_UNIT,
2094 		[DMAR_DSM_FUNC_ATSR] = ACPI_DMAR_TYPE_ROOT_ATS,
2095 		[DMAR_DSM_FUNC_RHSA] = ACPI_DMAR_TYPE_HARDWARE_AFFINITY,
2096 	};
2097 
2098 	if (!dmar_detect_dsm(handle, func))
2099 		return 0;
2100 
2101 	obj = acpi_evaluate_dsm_typed(handle, &dmar_hp_guid, DMAR_DSM_REV_ID,
2102 				      func, NULL, ACPI_TYPE_BUFFER);
2103 	if (!obj)
2104 		return -ENODEV;
2105 
2106 	memset(&callback, 0, sizeof(callback));
2107 	callback.cb[res_type[func]] = handler;
2108 	callback.arg[res_type[func]] = arg;
2109 	start = (struct acpi_dmar_header *)obj->buffer.pointer;
2110 	ret = dmar_walk_remapping_entries(start, obj->buffer.length, &callback);
2111 
2112 	ACPI_FREE(obj);
2113 
2114 	return ret;
2115 }
2116 
dmar_hp_add_drhd(struct acpi_dmar_header * header,void * arg)2117 static int dmar_hp_add_drhd(struct acpi_dmar_header *header, void *arg)
2118 {
2119 	int ret;
2120 	struct dmar_drhd_unit *dmaru;
2121 
2122 	dmaru = dmar_find_dmaru((struct acpi_dmar_hardware_unit *)header);
2123 	if (!dmaru)
2124 		return -ENODEV;
2125 
2126 	ret = dmar_ir_hotplug(dmaru, true);
2127 	if (ret == 0)
2128 		ret = dmar_iommu_hotplug(dmaru, true);
2129 
2130 	return ret;
2131 }
2132 
dmar_hp_remove_drhd(struct acpi_dmar_header * header,void * arg)2133 static int dmar_hp_remove_drhd(struct acpi_dmar_header *header, void *arg)
2134 {
2135 	int i, ret;
2136 	struct device *dev;
2137 	struct dmar_drhd_unit *dmaru;
2138 
2139 	dmaru = dmar_find_dmaru((struct acpi_dmar_hardware_unit *)header);
2140 	if (!dmaru)
2141 		return 0;
2142 
2143 	/*
2144 	 * All PCI devices managed by this unit should have been destroyed.
2145 	 */
2146 	if (!dmaru->include_all && dmaru->devices && dmaru->devices_cnt) {
2147 		for_each_active_dev_scope(dmaru->devices,
2148 					  dmaru->devices_cnt, i, dev)
2149 			return -EBUSY;
2150 	}
2151 
2152 	ret = dmar_ir_hotplug(dmaru, false);
2153 	if (ret == 0)
2154 		ret = dmar_iommu_hotplug(dmaru, false);
2155 
2156 	return ret;
2157 }
2158 
dmar_hp_release_drhd(struct acpi_dmar_header * header,void * arg)2159 static int dmar_hp_release_drhd(struct acpi_dmar_header *header, void *arg)
2160 {
2161 	struct dmar_drhd_unit *dmaru;
2162 
2163 	dmaru = dmar_find_dmaru((struct acpi_dmar_hardware_unit *)header);
2164 	if (dmaru) {
2165 		list_del_rcu(&dmaru->list);
2166 		synchronize_rcu();
2167 		dmar_free_drhd(dmaru);
2168 	}
2169 
2170 	return 0;
2171 }
2172 
dmar_hotplug_insert(acpi_handle handle)2173 static int dmar_hotplug_insert(acpi_handle handle)
2174 {
2175 	int ret;
2176 	int drhd_count = 0;
2177 
2178 	ret = dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2179 				     &dmar_validate_one_drhd, (void *)1);
2180 	if (ret)
2181 		goto out;
2182 
2183 	ret = dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2184 				     &dmar_parse_one_drhd, (void *)&drhd_count);
2185 	if (ret == 0 && drhd_count == 0) {
2186 		pr_warn(FW_BUG "No DRHD structures in buffer returned by _DSM method\n");
2187 		goto out;
2188 	} else if (ret) {
2189 		goto release_drhd;
2190 	}
2191 
2192 	ret = dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_RHSA,
2193 				     &dmar_parse_one_rhsa, NULL);
2194 	if (ret)
2195 		goto release_drhd;
2196 
2197 	ret = dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_ATSR,
2198 				     &dmar_parse_one_atsr, NULL);
2199 	if (ret)
2200 		goto release_atsr;
2201 
2202 	ret = dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2203 				     &dmar_hp_add_drhd, NULL);
2204 	if (!ret)
2205 		return 0;
2206 
2207 	dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2208 			       &dmar_hp_remove_drhd, NULL);
2209 release_atsr:
2210 	dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_ATSR,
2211 			       &dmar_release_one_atsr, NULL);
2212 release_drhd:
2213 	dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2214 			       &dmar_hp_release_drhd, NULL);
2215 out:
2216 	return ret;
2217 }
2218 
dmar_hotplug_remove(acpi_handle handle)2219 static int dmar_hotplug_remove(acpi_handle handle)
2220 {
2221 	int ret;
2222 
2223 	ret = dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_ATSR,
2224 				     &dmar_check_one_atsr, NULL);
2225 	if (ret)
2226 		return ret;
2227 
2228 	ret = dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2229 				     &dmar_hp_remove_drhd, NULL);
2230 	if (ret == 0) {
2231 		WARN_ON(dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_ATSR,
2232 					       &dmar_release_one_atsr, NULL));
2233 		WARN_ON(dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2234 					       &dmar_hp_release_drhd, NULL));
2235 	} else {
2236 		dmar_walk_dsm_resource(handle, DMAR_DSM_FUNC_DRHD,
2237 				       &dmar_hp_add_drhd, NULL);
2238 	}
2239 
2240 	return ret;
2241 }
2242 
dmar_get_dsm_handle(acpi_handle handle,u32 lvl,void * context,void ** retval)2243 static acpi_status dmar_get_dsm_handle(acpi_handle handle, u32 lvl,
2244 				       void *context, void **retval)
2245 {
2246 	acpi_handle *phdl = retval;
2247 
2248 	if (dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) {
2249 		*phdl = handle;
2250 		return AE_CTRL_TERMINATE;
2251 	}
2252 
2253 	return AE_OK;
2254 }
2255 
dmar_device_hotplug(acpi_handle handle,bool insert)2256 static int dmar_device_hotplug(acpi_handle handle, bool insert)
2257 {
2258 	int ret;
2259 	acpi_handle tmp = NULL;
2260 	acpi_status status;
2261 
2262 	if (!dmar_in_use())
2263 		return 0;
2264 
2265 	if (dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) {
2266 		tmp = handle;
2267 	} else {
2268 		status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
2269 					     ACPI_UINT32_MAX,
2270 					     dmar_get_dsm_handle,
2271 					     NULL, NULL, &tmp);
2272 		if (ACPI_FAILURE(status)) {
2273 			pr_warn("Failed to locate _DSM method.\n");
2274 			return -ENXIO;
2275 		}
2276 	}
2277 	if (tmp == NULL)
2278 		return 0;
2279 
2280 	down_write(&dmar_global_lock);
2281 	if (insert)
2282 		ret = dmar_hotplug_insert(tmp);
2283 	else
2284 		ret = dmar_hotplug_remove(tmp);
2285 	up_write(&dmar_global_lock);
2286 
2287 	return ret;
2288 }
2289 
dmar_device_add(acpi_handle handle)2290 int dmar_device_add(acpi_handle handle)
2291 {
2292 	return dmar_device_hotplug(handle, true);
2293 }
2294 
dmar_device_remove(acpi_handle handle)2295 int dmar_device_remove(acpi_handle handle)
2296 {
2297 	return dmar_device_hotplug(handle, false);
2298 }
2299 
2300 /*
2301  * dmar_platform_optin - Is %DMA_CTRL_PLATFORM_OPT_IN_FLAG set in DMAR table
2302  *
2303  * Returns true if the platform has %DMA_CTRL_PLATFORM_OPT_IN_FLAG set in
2304  * the ACPI DMAR table. This means that the platform boot firmware has made
2305  * sure no device can issue DMA outside of RMRR regions.
2306  */
dmar_platform_optin(void)2307 bool dmar_platform_optin(void)
2308 {
2309 	struct acpi_table_dmar *dmar;
2310 	acpi_status status;
2311 	bool ret;
2312 
2313 	status = acpi_get_table(ACPI_SIG_DMAR, 0,
2314 				(struct acpi_table_header **)&dmar);
2315 	if (ACPI_FAILURE(status))
2316 		return false;
2317 
2318 	ret = !!(dmar->flags & DMAR_PLATFORM_OPT_IN);
2319 	acpi_put_table((struct acpi_table_header *)dmar);
2320 
2321 	return ret;
2322 }
2323 EXPORT_SYMBOL_GPL(dmar_platform_optin);
2324