1 // SPDX-License-Identifier: GPL-2.0
2 
3 #define pr_fmt(fmt)     "DMAR-IR: " fmt
4 
5 #include <linux/interrupt.h>
6 #include <linux/dmar.h>
7 #include <linux/spinlock.h>
8 #include <linux/slab.h>
9 #include <linux/jiffies.h>
10 #include <linux/hpet.h>
11 #include <linux/pci.h>
12 #include <linux/irq.h>
13 #include <linux/intel-iommu.h>
14 #include <linux/acpi.h>
15 #include <linux/irqdomain.h>
16 #include <linux/crash_dump.h>
17 #include <asm/io_apic.h>
18 #include <asm/apic.h>
19 #include <asm/smp.h>
20 #include <asm/cpu.h>
21 #include <asm/irq_remapping.h>
22 #include <asm/pci-direct.h>
23 #include <asm/msidef.h>
24 
25 #include "../irq_remapping.h"
26 
27 enum irq_mode {
28 	IRQ_REMAPPING,
29 	IRQ_POSTING,
30 };
31 
32 struct ioapic_scope {
33 	struct intel_iommu *iommu;
34 	unsigned int id;
35 	unsigned int bus;	/* PCI bus number */
36 	unsigned int devfn;	/* PCI devfn number */
37 };
38 
39 struct hpet_scope {
40 	struct intel_iommu *iommu;
41 	u8 id;
42 	unsigned int bus;
43 	unsigned int devfn;
44 };
45 
46 struct irq_2_iommu {
47 	struct intel_iommu *iommu;
48 	u16 irte_index;
49 	u16 sub_handle;
50 	u8  irte_mask;
51 	enum irq_mode mode;
52 };
53 
54 struct intel_ir_data {
55 	struct irq_2_iommu			irq_2_iommu;
56 	struct irte				irte_entry;
57 	union {
58 		struct msi_msg			msi_entry;
59 	};
60 };
61 
62 #define IR_X2APIC_MODE(mode) (mode ? (1 << 11) : 0)
63 #define IRTE_DEST(dest) ((eim_mode) ? dest : dest << 8)
64 
65 static int __read_mostly eim_mode;
66 static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
67 static struct hpet_scope ir_hpet[MAX_HPET_TBS];
68 
69 /*
70  * Lock ordering:
71  * ->dmar_global_lock
72  *	->irq_2_ir_lock
73  *		->qi->q_lock
74  *	->iommu->register_lock
75  * Note:
76  * intel_irq_remap_ops.{supported,prepare,enable,disable,reenable} are called
77  * in single-threaded environment with interrupt disabled, so no need to tabke
78  * the dmar_global_lock.
79  */
80 DEFINE_RAW_SPINLOCK(irq_2_ir_lock);
81 static const struct irq_domain_ops intel_ir_domain_ops;
82 
83 static void iommu_disable_irq_remapping(struct intel_iommu *iommu);
84 static int __init parse_ioapics_under_ir(void);
85 
ir_pre_enabled(struct intel_iommu * iommu)86 static bool ir_pre_enabled(struct intel_iommu *iommu)
87 {
88 	return (iommu->flags & VTD_FLAG_IRQ_REMAP_PRE_ENABLED);
89 }
90 
clear_ir_pre_enabled(struct intel_iommu * iommu)91 static void clear_ir_pre_enabled(struct intel_iommu *iommu)
92 {
93 	iommu->flags &= ~VTD_FLAG_IRQ_REMAP_PRE_ENABLED;
94 }
95 
init_ir_status(struct intel_iommu * iommu)96 static void init_ir_status(struct intel_iommu *iommu)
97 {
98 	u32 gsts;
99 
100 	gsts = readl(iommu->reg + DMAR_GSTS_REG);
101 	if (gsts & DMA_GSTS_IRES)
102 		iommu->flags |= VTD_FLAG_IRQ_REMAP_PRE_ENABLED;
103 }
104 
alloc_irte(struct intel_iommu * iommu,struct irq_2_iommu * irq_iommu,u16 count)105 static int alloc_irte(struct intel_iommu *iommu,
106 		      struct irq_2_iommu *irq_iommu, u16 count)
107 {
108 	struct ir_table *table = iommu->ir_table;
109 	unsigned int mask = 0;
110 	unsigned long flags;
111 	int index;
112 
113 	if (!count || !irq_iommu)
114 		return -1;
115 
116 	if (count > 1) {
117 		count = __roundup_pow_of_two(count);
118 		mask = ilog2(count);
119 	}
120 
121 	if (mask > ecap_max_handle_mask(iommu->ecap)) {
122 		pr_err("Requested mask %x exceeds the max invalidation handle"
123 		       " mask value %Lx\n", mask,
124 		       ecap_max_handle_mask(iommu->ecap));
125 		return -1;
126 	}
127 
128 	raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
129 	index = bitmap_find_free_region(table->bitmap,
130 					INTR_REMAP_TABLE_ENTRIES, mask);
131 	if (index < 0) {
132 		pr_warn("IR%d: can't allocate an IRTE\n", iommu->seq_id);
133 	} else {
134 		irq_iommu->iommu = iommu;
135 		irq_iommu->irte_index =  index;
136 		irq_iommu->sub_handle = 0;
137 		irq_iommu->irte_mask = mask;
138 		irq_iommu->mode = IRQ_REMAPPING;
139 	}
140 	raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
141 
142 	return index;
143 }
144 
qi_flush_iec(struct intel_iommu * iommu,int index,int mask)145 static int qi_flush_iec(struct intel_iommu *iommu, int index, int mask)
146 {
147 	struct qi_desc desc;
148 
149 	desc.qw0 = QI_IEC_IIDEX(index) | QI_IEC_TYPE | QI_IEC_IM(mask)
150 		   | QI_IEC_SELECTIVE;
151 	desc.qw1 = 0;
152 	desc.qw2 = 0;
153 	desc.qw3 = 0;
154 
155 	return qi_submit_sync(iommu, &desc, 1, 0);
156 }
157 
modify_irte(struct irq_2_iommu * irq_iommu,struct irte * irte_modified)158 static int modify_irte(struct irq_2_iommu *irq_iommu,
159 		       struct irte *irte_modified)
160 {
161 	struct intel_iommu *iommu;
162 	unsigned long flags;
163 	struct irte *irte;
164 	int rc, index;
165 
166 	if (!irq_iommu)
167 		return -1;
168 
169 	raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
170 
171 	iommu = irq_iommu->iommu;
172 
173 	index = irq_iommu->irte_index + irq_iommu->sub_handle;
174 	irte = &iommu->ir_table->base[index];
175 
176 #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE)
177 	if ((irte->pst == 1) || (irte_modified->pst == 1)) {
178 		bool ret;
179 
180 		ret = cmpxchg_double(&irte->low, &irte->high,
181 				     irte->low, irte->high,
182 				     irte_modified->low, irte_modified->high);
183 		/*
184 		 * We use cmpxchg16 to atomically update the 128-bit IRTE,
185 		 * and it cannot be updated by the hardware or other processors
186 		 * behind us, so the return value of cmpxchg16 should be the
187 		 * same as the old value.
188 		 */
189 		WARN_ON(!ret);
190 	} else
191 #endif
192 	{
193 		set_64bit(&irte->low, irte_modified->low);
194 		set_64bit(&irte->high, irte_modified->high);
195 	}
196 	__iommu_flush_cache(iommu, irte, sizeof(*irte));
197 
198 	rc = qi_flush_iec(iommu, index, 0);
199 
200 	/* Update iommu mode according to the IRTE mode */
201 	irq_iommu->mode = irte->pst ? IRQ_POSTING : IRQ_REMAPPING;
202 	raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
203 
204 	return rc;
205 }
206 
map_hpet_to_ir(u8 hpet_id)207 static struct irq_domain *map_hpet_to_ir(u8 hpet_id)
208 {
209 	int i;
210 
211 	for (i = 0; i < MAX_HPET_TBS; i++) {
212 		if (ir_hpet[i].id == hpet_id && ir_hpet[i].iommu)
213 			return ir_hpet[i].iommu->ir_domain;
214 	}
215 	return NULL;
216 }
217 
map_ioapic_to_iommu(int apic)218 static struct intel_iommu *map_ioapic_to_iommu(int apic)
219 {
220 	int i;
221 
222 	for (i = 0; i < MAX_IO_APICS; i++) {
223 		if (ir_ioapic[i].id == apic && ir_ioapic[i].iommu)
224 			return ir_ioapic[i].iommu;
225 	}
226 	return NULL;
227 }
228 
map_ioapic_to_ir(int apic)229 static struct irq_domain *map_ioapic_to_ir(int apic)
230 {
231 	struct intel_iommu *iommu = map_ioapic_to_iommu(apic);
232 
233 	return iommu ? iommu->ir_domain : NULL;
234 }
235 
map_dev_to_ir(struct pci_dev * dev)236 static struct irq_domain *map_dev_to_ir(struct pci_dev *dev)
237 {
238 	struct dmar_drhd_unit *drhd = dmar_find_matched_drhd_unit(dev);
239 
240 	return drhd ? drhd->iommu->ir_msi_domain : NULL;
241 }
242 
clear_entries(struct irq_2_iommu * irq_iommu)243 static int clear_entries(struct irq_2_iommu *irq_iommu)
244 {
245 	struct irte *start, *entry, *end;
246 	struct intel_iommu *iommu;
247 	int index;
248 
249 	if (irq_iommu->sub_handle)
250 		return 0;
251 
252 	iommu = irq_iommu->iommu;
253 	index = irq_iommu->irte_index;
254 
255 	start = iommu->ir_table->base + index;
256 	end = start + (1 << irq_iommu->irte_mask);
257 
258 	for (entry = start; entry < end; entry++) {
259 		set_64bit(&entry->low, 0);
260 		set_64bit(&entry->high, 0);
261 	}
262 	bitmap_release_region(iommu->ir_table->bitmap, index,
263 			      irq_iommu->irte_mask);
264 
265 	return qi_flush_iec(iommu, index, irq_iommu->irte_mask);
266 }
267 
268 /*
269  * source validation type
270  */
271 #define SVT_NO_VERIFY		0x0  /* no verification is required */
272 #define SVT_VERIFY_SID_SQ	0x1  /* verify using SID and SQ fields */
273 #define SVT_VERIFY_BUS		0x2  /* verify bus of request-id */
274 
275 /*
276  * source-id qualifier
277  */
278 #define SQ_ALL_16	0x0  /* verify all 16 bits of request-id */
279 #define SQ_13_IGNORE_1	0x1  /* verify most significant 13 bits, ignore
280 			      * the third least significant bit
281 			      */
282 #define SQ_13_IGNORE_2	0x2  /* verify most significant 13 bits, ignore
283 			      * the second and third least significant bits
284 			      */
285 #define SQ_13_IGNORE_3	0x3  /* verify most significant 13 bits, ignore
286 			      * the least three significant bits
287 			      */
288 
289 /*
290  * set SVT, SQ and SID fields of irte to verify
291  * source ids of interrupt requests
292  */
set_irte_sid(struct irte * irte,unsigned int svt,unsigned int sq,unsigned int sid)293 static void set_irte_sid(struct irte *irte, unsigned int svt,
294 			 unsigned int sq, unsigned int sid)
295 {
296 	if (disable_sourceid_checking)
297 		svt = SVT_NO_VERIFY;
298 	irte->svt = svt;
299 	irte->sq = sq;
300 	irte->sid = sid;
301 }
302 
303 /*
304  * Set an IRTE to match only the bus number. Interrupt requests that reference
305  * this IRTE must have a requester-id whose bus number is between or equal
306  * to the start_bus and end_bus arguments.
307  */
set_irte_verify_bus(struct irte * irte,unsigned int start_bus,unsigned int end_bus)308 static void set_irte_verify_bus(struct irte *irte, unsigned int start_bus,
309 				unsigned int end_bus)
310 {
311 	set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
312 		     (start_bus << 8) | end_bus);
313 }
314 
set_ioapic_sid(struct irte * irte,int apic)315 static int set_ioapic_sid(struct irte *irte, int apic)
316 {
317 	int i;
318 	u16 sid = 0;
319 
320 	if (!irte)
321 		return -1;
322 
323 	down_read(&dmar_global_lock);
324 	for (i = 0; i < MAX_IO_APICS; i++) {
325 		if (ir_ioapic[i].iommu && ir_ioapic[i].id == apic) {
326 			sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn;
327 			break;
328 		}
329 	}
330 	up_read(&dmar_global_lock);
331 
332 	if (sid == 0) {
333 		pr_warn("Failed to set source-id of IOAPIC (%d)\n", apic);
334 		return -1;
335 	}
336 
337 	set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, sid);
338 
339 	return 0;
340 }
341 
set_hpet_sid(struct irte * irte,u8 id)342 static int set_hpet_sid(struct irte *irte, u8 id)
343 {
344 	int i;
345 	u16 sid = 0;
346 
347 	if (!irte)
348 		return -1;
349 
350 	down_read(&dmar_global_lock);
351 	for (i = 0; i < MAX_HPET_TBS; i++) {
352 		if (ir_hpet[i].iommu && ir_hpet[i].id == id) {
353 			sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn;
354 			break;
355 		}
356 	}
357 	up_read(&dmar_global_lock);
358 
359 	if (sid == 0) {
360 		pr_warn("Failed to set source-id of HPET block (%d)\n", id);
361 		return -1;
362 	}
363 
364 	/*
365 	 * Should really use SQ_ALL_16. Some platforms are broken.
366 	 * While we figure out the right quirks for these broken platforms, use
367 	 * SQ_13_IGNORE_3 for now.
368 	 */
369 	set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_13_IGNORE_3, sid);
370 
371 	return 0;
372 }
373 
374 struct set_msi_sid_data {
375 	struct pci_dev *pdev;
376 	u16 alias;
377 	int count;
378 	int busmatch_count;
379 };
380 
set_msi_sid_cb(struct pci_dev * pdev,u16 alias,void * opaque)381 static int set_msi_sid_cb(struct pci_dev *pdev, u16 alias, void *opaque)
382 {
383 	struct set_msi_sid_data *data = opaque;
384 
385 	if (data->count == 0 || PCI_BUS_NUM(alias) == PCI_BUS_NUM(data->alias))
386 		data->busmatch_count++;
387 
388 	data->pdev = pdev;
389 	data->alias = alias;
390 	data->count++;
391 
392 	return 0;
393 }
394 
set_msi_sid(struct irte * irte,struct pci_dev * dev)395 static int set_msi_sid(struct irte *irte, struct pci_dev *dev)
396 {
397 	struct set_msi_sid_data data;
398 
399 	if (!irte || !dev)
400 		return -1;
401 
402 	data.count = 0;
403 	data.busmatch_count = 0;
404 	pci_for_each_dma_alias(dev, set_msi_sid_cb, &data);
405 
406 	/*
407 	 * DMA alias provides us with a PCI device and alias.  The only case
408 	 * where the it will return an alias on a different bus than the
409 	 * device is the case of a PCIe-to-PCI bridge, where the alias is for
410 	 * the subordinate bus.  In this case we can only verify the bus.
411 	 *
412 	 * If there are multiple aliases, all with the same bus number,
413 	 * then all we can do is verify the bus. This is typical in NTB
414 	 * hardware which use proxy IDs where the device will generate traffic
415 	 * from multiple devfn numbers on the same bus.
416 	 *
417 	 * If the alias device is on a different bus than our source device
418 	 * then we have a topology based alias, use it.
419 	 *
420 	 * Otherwise, the alias is for a device DMA quirk and we cannot
421 	 * assume that MSI uses the same requester ID.  Therefore use the
422 	 * original device.
423 	 */
424 	if (PCI_BUS_NUM(data.alias) != data.pdev->bus->number)
425 		set_irte_verify_bus(irte, PCI_BUS_NUM(data.alias),
426 				    dev->bus->number);
427 	else if (data.count >= 2 && data.busmatch_count == data.count)
428 		set_irte_verify_bus(irte, dev->bus->number, dev->bus->number);
429 	else if (data.pdev->bus->number != dev->bus->number)
430 		set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, data.alias);
431 	else
432 		set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
433 			     pci_dev_id(dev));
434 
435 	return 0;
436 }
437 
iommu_load_old_irte(struct intel_iommu * iommu)438 static int iommu_load_old_irte(struct intel_iommu *iommu)
439 {
440 	struct irte *old_ir_table;
441 	phys_addr_t irt_phys;
442 	unsigned int i;
443 	size_t size;
444 	u64 irta;
445 
446 	/* Check whether the old ir-table has the same size as ours */
447 	irta = dmar_readq(iommu->reg + DMAR_IRTA_REG);
448 	if ((irta & INTR_REMAP_TABLE_REG_SIZE_MASK)
449 	     != INTR_REMAP_TABLE_REG_SIZE)
450 		return -EINVAL;
451 
452 	irt_phys = irta & VTD_PAGE_MASK;
453 	size     = INTR_REMAP_TABLE_ENTRIES*sizeof(struct irte);
454 
455 	/* Map the old IR table */
456 	old_ir_table = memremap(irt_phys, size, MEMREMAP_WB);
457 	if (!old_ir_table)
458 		return -ENOMEM;
459 
460 	/* Copy data over */
461 	memcpy(iommu->ir_table->base, old_ir_table, size);
462 
463 	__iommu_flush_cache(iommu, iommu->ir_table->base, size);
464 
465 	/*
466 	 * Now check the table for used entries and mark those as
467 	 * allocated in the bitmap
468 	 */
469 	for (i = 0; i < INTR_REMAP_TABLE_ENTRIES; i++) {
470 		if (iommu->ir_table->base[i].present)
471 			bitmap_set(iommu->ir_table->bitmap, i, 1);
472 	}
473 
474 	memunmap(old_ir_table);
475 
476 	return 0;
477 }
478 
479 
iommu_set_irq_remapping(struct intel_iommu * iommu,int mode)480 static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
481 {
482 	unsigned long flags;
483 	u64 addr;
484 	u32 sts;
485 
486 	addr = virt_to_phys((void *)iommu->ir_table->base);
487 
488 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
489 
490 	dmar_writeq(iommu->reg + DMAR_IRTA_REG,
491 		    (addr) | IR_X2APIC_MODE(mode) | INTR_REMAP_TABLE_REG_SIZE);
492 
493 	/* Set interrupt-remapping table pointer */
494 	writel(iommu->gcmd | DMA_GCMD_SIRTP, iommu->reg + DMAR_GCMD_REG);
495 
496 	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
497 		      readl, (sts & DMA_GSTS_IRTPS), sts);
498 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
499 
500 	/*
501 	 * Global invalidation of interrupt entry cache to make sure the
502 	 * hardware uses the new irq remapping table.
503 	 */
504 	qi_global_iec(iommu);
505 }
506 
iommu_enable_irq_remapping(struct intel_iommu * iommu)507 static void iommu_enable_irq_remapping(struct intel_iommu *iommu)
508 {
509 	unsigned long flags;
510 	u32 sts;
511 
512 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
513 
514 	/* Enable interrupt-remapping */
515 	iommu->gcmd |= DMA_GCMD_IRE;
516 	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
517 	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
518 		      readl, (sts & DMA_GSTS_IRES), sts);
519 
520 	/* Block compatibility-format MSIs */
521 	if (sts & DMA_GSTS_CFIS) {
522 		iommu->gcmd &= ~DMA_GCMD_CFI;
523 		writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
524 		IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
525 			      readl, !(sts & DMA_GSTS_CFIS), sts);
526 	}
527 
528 	/*
529 	 * With CFI clear in the Global Command register, we should be
530 	 * protected from dangerous (i.e. compatibility) interrupts
531 	 * regardless of x2apic status.  Check just to be sure.
532 	 */
533 	if (sts & DMA_GSTS_CFIS)
534 		WARN(1, KERN_WARNING
535 			"Compatibility-format IRQs enabled despite intr remapping;\n"
536 			"you are vulnerable to IRQ injection.\n");
537 
538 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
539 }
540 
intel_setup_irq_remapping(struct intel_iommu * iommu)541 static int intel_setup_irq_remapping(struct intel_iommu *iommu)
542 {
543 	struct ir_table *ir_table;
544 	struct fwnode_handle *fn;
545 	unsigned long *bitmap;
546 	struct page *pages;
547 
548 	if (iommu->ir_table)
549 		return 0;
550 
551 	ir_table = kzalloc(sizeof(struct ir_table), GFP_KERNEL);
552 	if (!ir_table)
553 		return -ENOMEM;
554 
555 	pages = alloc_pages_node(iommu->node, GFP_KERNEL | __GFP_ZERO,
556 				 INTR_REMAP_PAGE_ORDER);
557 	if (!pages) {
558 		pr_err("IR%d: failed to allocate pages of order %d\n",
559 		       iommu->seq_id, INTR_REMAP_PAGE_ORDER);
560 		goto out_free_table;
561 	}
562 
563 	bitmap = bitmap_zalloc(INTR_REMAP_TABLE_ENTRIES, GFP_ATOMIC);
564 	if (bitmap == NULL) {
565 		pr_err("IR%d: failed to allocate bitmap\n", iommu->seq_id);
566 		goto out_free_pages;
567 	}
568 
569 	fn = irq_domain_alloc_named_id_fwnode("INTEL-IR", iommu->seq_id);
570 	if (!fn)
571 		goto out_free_bitmap;
572 
573 	iommu->ir_domain =
574 		irq_domain_create_hierarchy(arch_get_ir_parent_domain(),
575 					    0, INTR_REMAP_TABLE_ENTRIES,
576 					    fn, &intel_ir_domain_ops,
577 					    iommu);
578 	if (!iommu->ir_domain) {
579 		irq_domain_free_fwnode(fn);
580 		pr_err("IR%d: failed to allocate irqdomain\n", iommu->seq_id);
581 		goto out_free_bitmap;
582 	}
583 	iommu->ir_msi_domain =
584 		arch_create_remap_msi_irq_domain(iommu->ir_domain,
585 						 "INTEL-IR-MSI",
586 						 iommu->seq_id);
587 
588 	ir_table->base = page_address(pages);
589 	ir_table->bitmap = bitmap;
590 	iommu->ir_table = ir_table;
591 
592 	/*
593 	 * If the queued invalidation is already initialized,
594 	 * shouldn't disable it.
595 	 */
596 	if (!iommu->qi) {
597 		/*
598 		 * Clear previous faults.
599 		 */
600 		dmar_fault(-1, iommu);
601 		dmar_disable_qi(iommu);
602 
603 		if (dmar_enable_qi(iommu)) {
604 			pr_err("Failed to enable queued invalidation\n");
605 			goto out_free_bitmap;
606 		}
607 	}
608 
609 	init_ir_status(iommu);
610 
611 	if (ir_pre_enabled(iommu)) {
612 		if (!is_kdump_kernel()) {
613 			pr_warn("IRQ remapping was enabled on %s but we are not in kdump mode\n",
614 				iommu->name);
615 			clear_ir_pre_enabled(iommu);
616 			iommu_disable_irq_remapping(iommu);
617 		} else if (iommu_load_old_irte(iommu))
618 			pr_err("Failed to copy IR table for %s from previous kernel\n",
619 			       iommu->name);
620 		else
621 			pr_info("Copied IR table for %s from previous kernel\n",
622 				iommu->name);
623 	}
624 
625 	iommu_set_irq_remapping(iommu, eim_mode);
626 
627 	return 0;
628 
629 out_free_bitmap:
630 	bitmap_free(bitmap);
631 out_free_pages:
632 	__free_pages(pages, INTR_REMAP_PAGE_ORDER);
633 out_free_table:
634 	kfree(ir_table);
635 
636 	iommu->ir_table  = NULL;
637 
638 	return -ENOMEM;
639 }
640 
intel_teardown_irq_remapping(struct intel_iommu * iommu)641 static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
642 {
643 	struct fwnode_handle *fn;
644 
645 	if (iommu && iommu->ir_table) {
646 		if (iommu->ir_msi_domain) {
647 			fn = iommu->ir_msi_domain->fwnode;
648 
649 			irq_domain_remove(iommu->ir_msi_domain);
650 			irq_domain_free_fwnode(fn);
651 			iommu->ir_msi_domain = NULL;
652 		}
653 		if (iommu->ir_domain) {
654 			fn = iommu->ir_domain->fwnode;
655 
656 			irq_domain_remove(iommu->ir_domain);
657 			irq_domain_free_fwnode(fn);
658 			iommu->ir_domain = NULL;
659 		}
660 		free_pages((unsigned long)iommu->ir_table->base,
661 			   INTR_REMAP_PAGE_ORDER);
662 		bitmap_free(iommu->ir_table->bitmap);
663 		kfree(iommu->ir_table);
664 		iommu->ir_table = NULL;
665 	}
666 }
667 
668 /*
669  * Disable Interrupt Remapping.
670  */
iommu_disable_irq_remapping(struct intel_iommu * iommu)671 static void iommu_disable_irq_remapping(struct intel_iommu *iommu)
672 {
673 	unsigned long flags;
674 	u32 sts;
675 
676 	if (!ecap_ir_support(iommu->ecap))
677 		return;
678 
679 	/*
680 	 * global invalidation of interrupt entry cache before disabling
681 	 * interrupt-remapping.
682 	 */
683 	qi_global_iec(iommu);
684 
685 	raw_spin_lock_irqsave(&iommu->register_lock, flags);
686 
687 	sts = readl(iommu->reg + DMAR_GSTS_REG);
688 	if (!(sts & DMA_GSTS_IRES))
689 		goto end;
690 
691 	iommu->gcmd &= ~DMA_GCMD_IRE;
692 	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
693 
694 	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
695 		      readl, !(sts & DMA_GSTS_IRES), sts);
696 
697 end:
698 	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
699 }
700 
dmar_x2apic_optout(void)701 static int __init dmar_x2apic_optout(void)
702 {
703 	struct acpi_table_dmar *dmar;
704 	dmar = (struct acpi_table_dmar *)dmar_tbl;
705 	if (!dmar || no_x2apic_optout)
706 		return 0;
707 	return dmar->flags & DMAR_X2APIC_OPT_OUT;
708 }
709 
intel_cleanup_irq_remapping(void)710 static void __init intel_cleanup_irq_remapping(void)
711 {
712 	struct dmar_drhd_unit *drhd;
713 	struct intel_iommu *iommu;
714 
715 	for_each_iommu(iommu, drhd) {
716 		if (ecap_ir_support(iommu->ecap)) {
717 			iommu_disable_irq_remapping(iommu);
718 			intel_teardown_irq_remapping(iommu);
719 		}
720 	}
721 
722 	if (x2apic_supported())
723 		pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n");
724 }
725 
intel_prepare_irq_remapping(void)726 static int __init intel_prepare_irq_remapping(void)
727 {
728 	struct dmar_drhd_unit *drhd;
729 	struct intel_iommu *iommu;
730 	int eim = 0;
731 
732 	if (irq_remap_broken) {
733 		pr_warn("This system BIOS has enabled interrupt remapping\n"
734 			"on a chipset that contains an erratum making that\n"
735 			"feature unstable.  To maintain system stability\n"
736 			"interrupt remapping is being disabled.  Please\n"
737 			"contact your BIOS vendor for an update\n");
738 		add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
739 		return -ENODEV;
740 	}
741 
742 	if (dmar_table_init() < 0)
743 		return -ENODEV;
744 
745 	if (!dmar_ir_support())
746 		return -ENODEV;
747 
748 	if (parse_ioapics_under_ir()) {
749 		pr_info("Not enabling interrupt remapping\n");
750 		goto error;
751 	}
752 
753 	/* First make sure all IOMMUs support IRQ remapping */
754 	for_each_iommu(iommu, drhd)
755 		if (!ecap_ir_support(iommu->ecap))
756 			goto error;
757 
758 	/* Detect remapping mode: lapic or x2apic */
759 	if (x2apic_supported()) {
760 		eim = !dmar_x2apic_optout();
761 		if (!eim) {
762 			pr_info("x2apic is disabled because BIOS sets x2apic opt out bit.");
763 			pr_info("Use 'intremap=no_x2apic_optout' to override the BIOS setting.\n");
764 		}
765 	}
766 
767 	for_each_iommu(iommu, drhd) {
768 		if (eim && !ecap_eim_support(iommu->ecap)) {
769 			pr_info("%s does not support EIM\n", iommu->name);
770 			eim = 0;
771 		}
772 	}
773 
774 	eim_mode = eim;
775 	if (eim)
776 		pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n");
777 
778 	/* Do the initializations early */
779 	for_each_iommu(iommu, drhd) {
780 		if (intel_setup_irq_remapping(iommu)) {
781 			pr_err("Failed to setup irq remapping for %s\n",
782 			       iommu->name);
783 			goto error;
784 		}
785 	}
786 
787 	return 0;
788 
789 error:
790 	intel_cleanup_irq_remapping();
791 	return -ENODEV;
792 }
793 
794 /*
795  * Set Posted-Interrupts capability.
796  */
set_irq_posting_cap(void)797 static inline void set_irq_posting_cap(void)
798 {
799 	struct dmar_drhd_unit *drhd;
800 	struct intel_iommu *iommu;
801 
802 	if (!disable_irq_post) {
803 		/*
804 		 * If IRTE is in posted format, the 'pda' field goes across the
805 		 * 64-bit boundary, we need use cmpxchg16b to atomically update
806 		 * it. We only expose posted-interrupt when X86_FEATURE_CX16
807 		 * is supported. Actually, hardware platforms supporting PI
808 		 * should have X86_FEATURE_CX16 support, this has been confirmed
809 		 * with Intel hardware guys.
810 		 */
811 		if (boot_cpu_has(X86_FEATURE_CX16))
812 			intel_irq_remap_ops.capability |= 1 << IRQ_POSTING_CAP;
813 
814 		for_each_iommu(iommu, drhd)
815 			if (!cap_pi_support(iommu->cap)) {
816 				intel_irq_remap_ops.capability &=
817 						~(1 << IRQ_POSTING_CAP);
818 				break;
819 			}
820 	}
821 }
822 
intel_enable_irq_remapping(void)823 static int __init intel_enable_irq_remapping(void)
824 {
825 	struct dmar_drhd_unit *drhd;
826 	struct intel_iommu *iommu;
827 	bool setup = false;
828 
829 	/*
830 	 * Setup Interrupt-remapping for all the DRHD's now.
831 	 */
832 	for_each_iommu(iommu, drhd) {
833 		if (!ir_pre_enabled(iommu))
834 			iommu_enable_irq_remapping(iommu);
835 		setup = true;
836 	}
837 
838 	if (!setup)
839 		goto error;
840 
841 	irq_remapping_enabled = 1;
842 
843 	set_irq_posting_cap();
844 
845 	pr_info("Enabled IRQ remapping in %s mode\n", eim_mode ? "x2apic" : "xapic");
846 
847 	return eim_mode ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
848 
849 error:
850 	intel_cleanup_irq_remapping();
851 	return -1;
852 }
853 
ir_parse_one_hpet_scope(struct acpi_dmar_device_scope * scope,struct intel_iommu * iommu,struct acpi_dmar_hardware_unit * drhd)854 static int ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope,
855 				   struct intel_iommu *iommu,
856 				   struct acpi_dmar_hardware_unit *drhd)
857 {
858 	struct acpi_dmar_pci_path *path;
859 	u8 bus;
860 	int count, free = -1;
861 
862 	bus = scope->bus;
863 	path = (struct acpi_dmar_pci_path *)(scope + 1);
864 	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
865 		/ sizeof(struct acpi_dmar_pci_path);
866 
867 	while (--count > 0) {
868 		/*
869 		 * Access PCI directly due to the PCI
870 		 * subsystem isn't initialized yet.
871 		 */
872 		bus = read_pci_config_byte(bus, path->device, path->function,
873 					   PCI_SECONDARY_BUS);
874 		path++;
875 	}
876 
877 	for (count = 0; count < MAX_HPET_TBS; count++) {
878 		if (ir_hpet[count].iommu == iommu &&
879 		    ir_hpet[count].id == scope->enumeration_id)
880 			return 0;
881 		else if (ir_hpet[count].iommu == NULL && free == -1)
882 			free = count;
883 	}
884 	if (free == -1) {
885 		pr_warn("Exceeded Max HPET blocks\n");
886 		return -ENOSPC;
887 	}
888 
889 	ir_hpet[free].iommu = iommu;
890 	ir_hpet[free].id    = scope->enumeration_id;
891 	ir_hpet[free].bus   = bus;
892 	ir_hpet[free].devfn = PCI_DEVFN(path->device, path->function);
893 	pr_info("HPET id %d under DRHD base 0x%Lx\n",
894 		scope->enumeration_id, drhd->address);
895 
896 	return 0;
897 }
898 
ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope * scope,struct intel_iommu * iommu,struct acpi_dmar_hardware_unit * drhd)899 static int ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
900 				     struct intel_iommu *iommu,
901 				     struct acpi_dmar_hardware_unit *drhd)
902 {
903 	struct acpi_dmar_pci_path *path;
904 	u8 bus;
905 	int count, free = -1;
906 
907 	bus = scope->bus;
908 	path = (struct acpi_dmar_pci_path *)(scope + 1);
909 	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
910 		/ sizeof(struct acpi_dmar_pci_path);
911 
912 	while (--count > 0) {
913 		/*
914 		 * Access PCI directly due to the PCI
915 		 * subsystem isn't initialized yet.
916 		 */
917 		bus = read_pci_config_byte(bus, path->device, path->function,
918 					   PCI_SECONDARY_BUS);
919 		path++;
920 	}
921 
922 	for (count = 0; count < MAX_IO_APICS; count++) {
923 		if (ir_ioapic[count].iommu == iommu &&
924 		    ir_ioapic[count].id == scope->enumeration_id)
925 			return 0;
926 		else if (ir_ioapic[count].iommu == NULL && free == -1)
927 			free = count;
928 	}
929 	if (free == -1) {
930 		pr_warn("Exceeded Max IO APICS\n");
931 		return -ENOSPC;
932 	}
933 
934 	ir_ioapic[free].bus   = bus;
935 	ir_ioapic[free].devfn = PCI_DEVFN(path->device, path->function);
936 	ir_ioapic[free].iommu = iommu;
937 	ir_ioapic[free].id    = scope->enumeration_id;
938 	pr_info("IOAPIC id %d under DRHD base  0x%Lx IOMMU %d\n",
939 		scope->enumeration_id, drhd->address, iommu->seq_id);
940 
941 	return 0;
942 }
943 
ir_parse_ioapic_hpet_scope(struct acpi_dmar_header * header,struct intel_iommu * iommu)944 static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_header *header,
945 				      struct intel_iommu *iommu)
946 {
947 	int ret = 0;
948 	struct acpi_dmar_hardware_unit *drhd;
949 	struct acpi_dmar_device_scope *scope;
950 	void *start, *end;
951 
952 	drhd = (struct acpi_dmar_hardware_unit *)header;
953 	start = (void *)(drhd + 1);
954 	end = ((void *)drhd) + header->length;
955 
956 	while (start < end && ret == 0) {
957 		scope = start;
958 		if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC)
959 			ret = ir_parse_one_ioapic_scope(scope, iommu, drhd);
960 		else if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_HPET)
961 			ret = ir_parse_one_hpet_scope(scope, iommu, drhd);
962 		start += scope->length;
963 	}
964 
965 	return ret;
966 }
967 
ir_remove_ioapic_hpet_scope(struct intel_iommu * iommu)968 static void ir_remove_ioapic_hpet_scope(struct intel_iommu *iommu)
969 {
970 	int i;
971 
972 	for (i = 0; i < MAX_HPET_TBS; i++)
973 		if (ir_hpet[i].iommu == iommu)
974 			ir_hpet[i].iommu = NULL;
975 
976 	for (i = 0; i < MAX_IO_APICS; i++)
977 		if (ir_ioapic[i].iommu == iommu)
978 			ir_ioapic[i].iommu = NULL;
979 }
980 
981 /*
982  * Finds the assocaition between IOAPIC's and its Interrupt-remapping
983  * hardware unit.
984  */
parse_ioapics_under_ir(void)985 static int __init parse_ioapics_under_ir(void)
986 {
987 	struct dmar_drhd_unit *drhd;
988 	struct intel_iommu *iommu;
989 	bool ir_supported = false;
990 	int ioapic_idx;
991 
992 	for_each_iommu(iommu, drhd) {
993 		int ret;
994 
995 		if (!ecap_ir_support(iommu->ecap))
996 			continue;
997 
998 		ret = ir_parse_ioapic_hpet_scope(drhd->hdr, iommu);
999 		if (ret)
1000 			return ret;
1001 
1002 		ir_supported = true;
1003 	}
1004 
1005 	if (!ir_supported)
1006 		return -ENODEV;
1007 
1008 	for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) {
1009 		int ioapic_id = mpc_ioapic_id(ioapic_idx);
1010 		if (!map_ioapic_to_iommu(ioapic_id)) {
1011 			pr_err(FW_BUG "ioapic %d has no mapping iommu, "
1012 			       "interrupt remapping will be disabled\n",
1013 			       ioapic_id);
1014 			return -1;
1015 		}
1016 	}
1017 
1018 	return 0;
1019 }
1020 
ir_dev_scope_init(void)1021 static int __init ir_dev_scope_init(void)
1022 {
1023 	int ret;
1024 
1025 	if (!irq_remapping_enabled)
1026 		return 0;
1027 
1028 	down_write(&dmar_global_lock);
1029 	ret = dmar_dev_scope_init();
1030 	up_write(&dmar_global_lock);
1031 
1032 	return ret;
1033 }
1034 rootfs_initcall(ir_dev_scope_init);
1035 
disable_irq_remapping(void)1036 static void disable_irq_remapping(void)
1037 {
1038 	struct dmar_drhd_unit *drhd;
1039 	struct intel_iommu *iommu = NULL;
1040 
1041 	/*
1042 	 * Disable Interrupt-remapping for all the DRHD's now.
1043 	 */
1044 	for_each_iommu(iommu, drhd) {
1045 		if (!ecap_ir_support(iommu->ecap))
1046 			continue;
1047 
1048 		iommu_disable_irq_remapping(iommu);
1049 	}
1050 
1051 	/*
1052 	 * Clear Posted-Interrupts capability.
1053 	 */
1054 	if (!disable_irq_post)
1055 		intel_irq_remap_ops.capability &= ~(1 << IRQ_POSTING_CAP);
1056 }
1057 
reenable_irq_remapping(int eim)1058 static int reenable_irq_remapping(int eim)
1059 {
1060 	struct dmar_drhd_unit *drhd;
1061 	bool setup = false;
1062 	struct intel_iommu *iommu = NULL;
1063 
1064 	for_each_iommu(iommu, drhd)
1065 		if (iommu->qi)
1066 			dmar_reenable_qi(iommu);
1067 
1068 	/*
1069 	 * Setup Interrupt-remapping for all the DRHD's now.
1070 	 */
1071 	for_each_iommu(iommu, drhd) {
1072 		if (!ecap_ir_support(iommu->ecap))
1073 			continue;
1074 
1075 		/* Set up interrupt remapping for iommu.*/
1076 		iommu_set_irq_remapping(iommu, eim);
1077 		iommu_enable_irq_remapping(iommu);
1078 		setup = true;
1079 	}
1080 
1081 	if (!setup)
1082 		goto error;
1083 
1084 	set_irq_posting_cap();
1085 
1086 	return 0;
1087 
1088 error:
1089 	/*
1090 	 * handle error condition gracefully here!
1091 	 */
1092 	return -1;
1093 }
1094 
1095 /*
1096  * Store the MSI remapping domain pointer in the device if enabled.
1097  *
1098  * This is called from dmar_pci_bus_add_dev() so it works even when DMA
1099  * remapping is disabled. Only update the pointer if the device is not
1100  * already handled by a non default PCI/MSI interrupt domain. This protects
1101  * e.g. VMD devices.
1102  */
intel_irq_remap_add_device(struct dmar_pci_notify_info * info)1103 void intel_irq_remap_add_device(struct dmar_pci_notify_info *info)
1104 {
1105 	if (!irq_remapping_enabled || pci_dev_has_special_msi_domain(info->dev))
1106 		return;
1107 
1108 	dev_set_msi_domain(&info->dev->dev, map_dev_to_ir(info->dev));
1109 }
1110 
prepare_irte(struct irte * irte,int vector,unsigned int dest)1111 static void prepare_irte(struct irte *irte, int vector, unsigned int dest)
1112 {
1113 	memset(irte, 0, sizeof(*irte));
1114 
1115 	irte->present = 1;
1116 	irte->dst_mode = apic->irq_dest_mode;
1117 	/*
1118 	 * Trigger mode in the IRTE will always be edge, and for IO-APIC, the
1119 	 * actual level or edge trigger will be setup in the IO-APIC
1120 	 * RTE. This will help simplify level triggered irq migration.
1121 	 * For more details, see the comments (in io_apic.c) explainig IO-APIC
1122 	 * irq migration in the presence of interrupt-remapping.
1123 	*/
1124 	irte->trigger_mode = 0;
1125 	irte->dlvry_mode = apic->irq_delivery_mode;
1126 	irte->vector = vector;
1127 	irte->dest_id = IRTE_DEST(dest);
1128 	irte->redir_hint = 1;
1129 }
1130 
intel_get_irq_domain(struct irq_alloc_info * info)1131 static struct irq_domain *intel_get_irq_domain(struct irq_alloc_info *info)
1132 {
1133 	if (!info)
1134 		return NULL;
1135 
1136 	switch (info->type) {
1137 	case X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT:
1138 		return map_ioapic_to_ir(info->devid);
1139 	case X86_IRQ_ALLOC_TYPE_HPET_GET_PARENT:
1140 		return map_hpet_to_ir(info->devid);
1141 	default:
1142 		WARN_ON_ONCE(1);
1143 		return NULL;
1144 	}
1145 }
1146 
1147 struct irq_remap_ops intel_irq_remap_ops = {
1148 	.prepare		= intel_prepare_irq_remapping,
1149 	.enable			= intel_enable_irq_remapping,
1150 	.disable		= disable_irq_remapping,
1151 	.reenable		= reenable_irq_remapping,
1152 	.enable_faulting	= enable_drhd_fault_handling,
1153 	.get_irq_domain		= intel_get_irq_domain,
1154 };
1155 
intel_ir_reconfigure_irte(struct irq_data * irqd,bool force)1156 static void intel_ir_reconfigure_irte(struct irq_data *irqd, bool force)
1157 {
1158 	struct intel_ir_data *ir_data = irqd->chip_data;
1159 	struct irte *irte = &ir_data->irte_entry;
1160 	struct irq_cfg *cfg = irqd_cfg(irqd);
1161 
1162 	/*
1163 	 * Atomically updates the IRTE with the new destination, vector
1164 	 * and flushes the interrupt entry cache.
1165 	 */
1166 	irte->vector = cfg->vector;
1167 	irte->dest_id = IRTE_DEST(cfg->dest_apicid);
1168 
1169 	/* Update the hardware only if the interrupt is in remapped mode. */
1170 	if (force || ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
1171 		modify_irte(&ir_data->irq_2_iommu, irte);
1172 }
1173 
1174 /*
1175  * Migrate the IO-APIC irq in the presence of intr-remapping.
1176  *
1177  * For both level and edge triggered, irq migration is a simple atomic
1178  * update(of vector and cpu destination) of IRTE and flush the hardware cache.
1179  *
1180  * For level triggered, we eliminate the io-apic RTE modification (with the
1181  * updated vector information), by using a virtual vector (io-apic pin number).
1182  * Real vector that is used for interrupting cpu will be coming from
1183  * the interrupt-remapping table entry.
1184  *
1185  * As the migration is a simple atomic update of IRTE, the same mechanism
1186  * is used to migrate MSI irq's in the presence of interrupt-remapping.
1187  */
1188 static int
intel_ir_set_affinity(struct irq_data * data,const struct cpumask * mask,bool force)1189 intel_ir_set_affinity(struct irq_data *data, const struct cpumask *mask,
1190 		      bool force)
1191 {
1192 	struct irq_data *parent = data->parent_data;
1193 	struct irq_cfg *cfg = irqd_cfg(data);
1194 	int ret;
1195 
1196 	ret = parent->chip->irq_set_affinity(parent, mask, force);
1197 	if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
1198 		return ret;
1199 
1200 	intel_ir_reconfigure_irte(data, false);
1201 	/*
1202 	 * After this point, all the interrupts will start arriving
1203 	 * at the new destination. So, time to cleanup the previous
1204 	 * vector allocation.
1205 	 */
1206 	send_cleanup_vector(cfg);
1207 
1208 	return IRQ_SET_MASK_OK_DONE;
1209 }
1210 
intel_ir_compose_msi_msg(struct irq_data * irq_data,struct msi_msg * msg)1211 static void intel_ir_compose_msi_msg(struct irq_data *irq_data,
1212 				     struct msi_msg *msg)
1213 {
1214 	struct intel_ir_data *ir_data = irq_data->chip_data;
1215 
1216 	*msg = ir_data->msi_entry;
1217 }
1218 
intel_ir_set_vcpu_affinity(struct irq_data * data,void * info)1219 static int intel_ir_set_vcpu_affinity(struct irq_data *data, void *info)
1220 {
1221 	struct intel_ir_data *ir_data = data->chip_data;
1222 	struct vcpu_data *vcpu_pi_info = info;
1223 
1224 	/* stop posting interrupts, back to remapping mode */
1225 	if (!vcpu_pi_info) {
1226 		modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry);
1227 	} else {
1228 		struct irte irte_pi;
1229 
1230 		/*
1231 		 * We are not caching the posted interrupt entry. We
1232 		 * copy the data from the remapped entry and modify
1233 		 * the fields which are relevant for posted mode. The
1234 		 * cached remapped entry is used for switching back to
1235 		 * remapped mode.
1236 		 */
1237 		memset(&irte_pi, 0, sizeof(irte_pi));
1238 		dmar_copy_shared_irte(&irte_pi, &ir_data->irte_entry);
1239 
1240 		/* Update the posted mode fields */
1241 		irte_pi.p_pst = 1;
1242 		irte_pi.p_urgent = 0;
1243 		irte_pi.p_vector = vcpu_pi_info->vector;
1244 		irte_pi.pda_l = (vcpu_pi_info->pi_desc_addr >>
1245 				(32 - PDA_LOW_BIT)) & ~(-1UL << PDA_LOW_BIT);
1246 		irte_pi.pda_h = (vcpu_pi_info->pi_desc_addr >> 32) &
1247 				~(-1UL << PDA_HIGH_BIT);
1248 
1249 		modify_irte(&ir_data->irq_2_iommu, &irte_pi);
1250 	}
1251 
1252 	return 0;
1253 }
1254 
1255 static struct irq_chip intel_ir_chip = {
1256 	.name			= "INTEL-IR",
1257 	.irq_ack		= apic_ack_irq,
1258 	.irq_set_affinity	= intel_ir_set_affinity,
1259 	.irq_compose_msi_msg	= intel_ir_compose_msi_msg,
1260 	.irq_set_vcpu_affinity	= intel_ir_set_vcpu_affinity,
1261 };
1262 
intel_irq_remapping_prepare_irte(struct intel_ir_data * data,struct irq_cfg * irq_cfg,struct irq_alloc_info * info,int index,int sub_handle)1263 static void intel_irq_remapping_prepare_irte(struct intel_ir_data *data,
1264 					     struct irq_cfg *irq_cfg,
1265 					     struct irq_alloc_info *info,
1266 					     int index, int sub_handle)
1267 {
1268 	struct IR_IO_APIC_route_entry *entry;
1269 	struct irte *irte = &data->irte_entry;
1270 	struct msi_msg *msg = &data->msi_entry;
1271 
1272 	prepare_irte(irte, irq_cfg->vector, irq_cfg->dest_apicid);
1273 	switch (info->type) {
1274 	case X86_IRQ_ALLOC_TYPE_IOAPIC:
1275 		/* Set source-id of interrupt request */
1276 		set_ioapic_sid(irte, info->devid);
1277 		apic_printk(APIC_VERBOSE, KERN_DEBUG "IOAPIC[%d]: Set IRTE entry (P:%d FPD:%d Dst_Mode:%d Redir_hint:%d Trig_Mode:%d Dlvry_Mode:%X Avail:%X Vector:%02X Dest:%08X SID:%04X SQ:%X SVT:%X)\n",
1278 			info->devid, irte->present, irte->fpd,
1279 			irte->dst_mode, irte->redir_hint,
1280 			irte->trigger_mode, irte->dlvry_mode,
1281 			irte->avail, irte->vector, irte->dest_id,
1282 			irte->sid, irte->sq, irte->svt);
1283 
1284 		entry = (struct IR_IO_APIC_route_entry *)info->ioapic.entry;
1285 		info->ioapic.entry = NULL;
1286 		memset(entry, 0, sizeof(*entry));
1287 		entry->index2	= (index >> 15) & 0x1;
1288 		entry->zero	= 0;
1289 		entry->format	= 1;
1290 		entry->index	= (index & 0x7fff);
1291 		/*
1292 		 * IO-APIC RTE will be configured with virtual vector.
1293 		 * irq handler will do the explicit EOI to the io-apic.
1294 		 */
1295 		entry->vector	= info->ioapic.pin;
1296 		entry->mask	= 0;			/* enable IRQ */
1297 		entry->trigger	= info->ioapic.trigger;
1298 		entry->polarity	= info->ioapic.polarity;
1299 		if (info->ioapic.trigger)
1300 			entry->mask = 1; /* Mask level triggered irqs. */
1301 		break;
1302 
1303 	case X86_IRQ_ALLOC_TYPE_HPET:
1304 	case X86_IRQ_ALLOC_TYPE_PCI_MSI:
1305 	case X86_IRQ_ALLOC_TYPE_PCI_MSIX:
1306 		if (info->type == X86_IRQ_ALLOC_TYPE_HPET)
1307 			set_hpet_sid(irte, info->devid);
1308 		else
1309 			set_msi_sid(irte, msi_desc_to_pci_dev(info->desc));
1310 
1311 		msg->address_hi = MSI_ADDR_BASE_HI;
1312 		msg->data = sub_handle;
1313 		msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT |
1314 				  MSI_ADDR_IR_SHV |
1315 				  MSI_ADDR_IR_INDEX1(index) |
1316 				  MSI_ADDR_IR_INDEX2(index);
1317 		break;
1318 
1319 	default:
1320 		BUG_ON(1);
1321 		break;
1322 	}
1323 }
1324 
intel_free_irq_resources(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)1325 static void intel_free_irq_resources(struct irq_domain *domain,
1326 				     unsigned int virq, unsigned int nr_irqs)
1327 {
1328 	struct irq_data *irq_data;
1329 	struct intel_ir_data *data;
1330 	struct irq_2_iommu *irq_iommu;
1331 	unsigned long flags;
1332 	int i;
1333 	for (i = 0; i < nr_irqs; i++) {
1334 		irq_data = irq_domain_get_irq_data(domain, virq  + i);
1335 		if (irq_data && irq_data->chip_data) {
1336 			data = irq_data->chip_data;
1337 			irq_iommu = &data->irq_2_iommu;
1338 			raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
1339 			clear_entries(irq_iommu);
1340 			raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
1341 			irq_domain_reset_irq_data(irq_data);
1342 			kfree(data);
1343 		}
1344 	}
1345 }
1346 
intel_irq_remapping_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)1347 static int intel_irq_remapping_alloc(struct irq_domain *domain,
1348 				     unsigned int virq, unsigned int nr_irqs,
1349 				     void *arg)
1350 {
1351 	struct intel_iommu *iommu = domain->host_data;
1352 	struct irq_alloc_info *info = arg;
1353 	struct intel_ir_data *data, *ird;
1354 	struct irq_data *irq_data;
1355 	struct irq_cfg *irq_cfg;
1356 	int i, ret, index;
1357 
1358 	if (!info || !iommu)
1359 		return -EINVAL;
1360 	if (nr_irqs > 1 && info->type != X86_IRQ_ALLOC_TYPE_PCI_MSI &&
1361 	    info->type != X86_IRQ_ALLOC_TYPE_PCI_MSIX)
1362 		return -EINVAL;
1363 
1364 	/*
1365 	 * With IRQ remapping enabled, don't need contiguous CPU vectors
1366 	 * to support multiple MSI interrupts.
1367 	 */
1368 	if (info->type == X86_IRQ_ALLOC_TYPE_PCI_MSI)
1369 		info->flags &= ~X86_IRQ_ALLOC_CONTIGUOUS_VECTORS;
1370 
1371 	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
1372 	if (ret < 0)
1373 		return ret;
1374 
1375 	ret = -ENOMEM;
1376 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1377 	if (!data)
1378 		goto out_free_parent;
1379 
1380 	down_read(&dmar_global_lock);
1381 	index = alloc_irte(iommu, &data->irq_2_iommu, nr_irqs);
1382 	up_read(&dmar_global_lock);
1383 	if (index < 0) {
1384 		pr_warn("Failed to allocate IRTE\n");
1385 		kfree(data);
1386 		goto out_free_parent;
1387 	}
1388 
1389 	for (i = 0; i < nr_irqs; i++) {
1390 		irq_data = irq_domain_get_irq_data(domain, virq + i);
1391 		irq_cfg = irqd_cfg(irq_data);
1392 		if (!irq_data || !irq_cfg) {
1393 			ret = -EINVAL;
1394 			goto out_free_data;
1395 		}
1396 
1397 		if (i > 0) {
1398 			ird = kzalloc(sizeof(*ird), GFP_KERNEL);
1399 			if (!ird)
1400 				goto out_free_data;
1401 			/* Initialize the common data */
1402 			ird->irq_2_iommu = data->irq_2_iommu;
1403 			ird->irq_2_iommu.sub_handle = i;
1404 		} else {
1405 			ird = data;
1406 		}
1407 
1408 		irq_data->hwirq = (index << 16) + i;
1409 		irq_data->chip_data = ird;
1410 		irq_data->chip = &intel_ir_chip;
1411 		intel_irq_remapping_prepare_irte(ird, irq_cfg, info, index, i);
1412 		irq_set_status_flags(virq + i, IRQ_MOVE_PCNTXT);
1413 	}
1414 	return 0;
1415 
1416 out_free_data:
1417 	intel_free_irq_resources(domain, virq, i);
1418 out_free_parent:
1419 	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1420 	return ret;
1421 }
1422 
intel_irq_remapping_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)1423 static void intel_irq_remapping_free(struct irq_domain *domain,
1424 				     unsigned int virq, unsigned int nr_irqs)
1425 {
1426 	intel_free_irq_resources(domain, virq, nr_irqs);
1427 	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1428 }
1429 
intel_irq_remapping_activate(struct irq_domain * domain,struct irq_data * irq_data,bool reserve)1430 static int intel_irq_remapping_activate(struct irq_domain *domain,
1431 					struct irq_data *irq_data, bool reserve)
1432 {
1433 	intel_ir_reconfigure_irte(irq_data, true);
1434 	return 0;
1435 }
1436 
intel_irq_remapping_deactivate(struct irq_domain * domain,struct irq_data * irq_data)1437 static void intel_irq_remapping_deactivate(struct irq_domain *domain,
1438 					   struct irq_data *irq_data)
1439 {
1440 	struct intel_ir_data *data = irq_data->chip_data;
1441 	struct irte entry;
1442 
1443 	memset(&entry, 0, sizeof(entry));
1444 	modify_irte(&data->irq_2_iommu, &entry);
1445 }
1446 
1447 static const struct irq_domain_ops intel_ir_domain_ops = {
1448 	.alloc = intel_irq_remapping_alloc,
1449 	.free = intel_irq_remapping_free,
1450 	.activate = intel_irq_remapping_activate,
1451 	.deactivate = intel_irq_remapping_deactivate,
1452 };
1453 
1454 /*
1455  * Support of Interrupt Remapping Unit Hotplug
1456  */
dmar_ir_add(struct dmar_drhd_unit * dmaru,struct intel_iommu * iommu)1457 static int dmar_ir_add(struct dmar_drhd_unit *dmaru, struct intel_iommu *iommu)
1458 {
1459 	int ret;
1460 	int eim = x2apic_enabled();
1461 
1462 	if (eim && !ecap_eim_support(iommu->ecap)) {
1463 		pr_info("DRHD %Lx: EIM not supported by DRHD, ecap %Lx\n",
1464 			iommu->reg_phys, iommu->ecap);
1465 		return -ENODEV;
1466 	}
1467 
1468 	if (ir_parse_ioapic_hpet_scope(dmaru->hdr, iommu)) {
1469 		pr_warn("DRHD %Lx: failed to parse managed IOAPIC/HPET\n",
1470 			iommu->reg_phys);
1471 		return -ENODEV;
1472 	}
1473 
1474 	/* TODO: check all IOAPICs are covered by IOMMU */
1475 
1476 	/* Setup Interrupt-remapping now. */
1477 	ret = intel_setup_irq_remapping(iommu);
1478 	if (ret) {
1479 		pr_err("Failed to setup irq remapping for %s\n",
1480 		       iommu->name);
1481 		intel_teardown_irq_remapping(iommu);
1482 		ir_remove_ioapic_hpet_scope(iommu);
1483 	} else {
1484 		iommu_enable_irq_remapping(iommu);
1485 	}
1486 
1487 	return ret;
1488 }
1489 
dmar_ir_hotplug(struct dmar_drhd_unit * dmaru,bool insert)1490 int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert)
1491 {
1492 	int ret = 0;
1493 	struct intel_iommu *iommu = dmaru->iommu;
1494 
1495 	if (!irq_remapping_enabled)
1496 		return 0;
1497 	if (iommu == NULL)
1498 		return -EINVAL;
1499 	if (!ecap_ir_support(iommu->ecap))
1500 		return 0;
1501 	if (irq_remapping_cap(IRQ_POSTING_CAP) &&
1502 	    !cap_pi_support(iommu->cap))
1503 		return -EBUSY;
1504 
1505 	if (insert) {
1506 		if (!iommu->ir_table)
1507 			ret = dmar_ir_add(dmaru, iommu);
1508 	} else {
1509 		if (iommu->ir_table) {
1510 			if (!bitmap_empty(iommu->ir_table->bitmap,
1511 					  INTR_REMAP_TABLE_ENTRIES)) {
1512 				ret = -EBUSY;
1513 			} else {
1514 				iommu_disable_irq_remapping(iommu);
1515 				intel_teardown_irq_remapping(iommu);
1516 				ir_remove_ioapic_hpet_scope(iommu);
1517 			}
1518 		}
1519 	}
1520 
1521 	return ret;
1522 }
1523