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   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
  27enum irq_mode {
  28	IRQ_REMAPPING,
  29	IRQ_POSTING,
  30};
  31
  32struct 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
  39struct hpet_scope {
  40	struct intel_iommu *iommu;
  41	u8 id;
  42	unsigned int bus;
  43	unsigned int devfn;
  44};
  45
  46struct 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
  54struct 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
  65static int __read_mostly eim_mode;
  66static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
  67static 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 */
  80DEFINE_RAW_SPINLOCK(irq_2_ir_lock);
  81static const struct irq_domain_ops intel_ir_domain_ops;
  82
  83static void iommu_disable_irq_remapping(struct intel_iommu *iommu);
  84static int __init parse_ioapics_under_ir(void);
  85
  86static bool ir_pre_enabled(struct intel_iommu *iommu)
  87{
  88	return (iommu->flags & VTD_FLAG_IRQ_REMAP_PRE_ENABLED);
  89}
  90
  91static void clear_ir_pre_enabled(struct intel_iommu *iommu)
  92{
  93	iommu->flags &= ~VTD_FLAG_IRQ_REMAP_PRE_ENABLED;
  94}
  95
  96static 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
 105static 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
 145static 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
 158static 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
 207static struct intel_iommu *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;
 214	return NULL;
 215}
 216
 217static struct intel_iommu *map_ioapic_to_ir(int apic)
 218{
 219	int i;
 220
 221	for (i = 0; i < MAX_IO_APICS; i++)
 222		if (ir_ioapic[i].id == apic && ir_ioapic[i].iommu)
 223			return ir_ioapic[i].iommu;
 224	return NULL;
 225}
 226
 227static struct intel_iommu *map_dev_to_ir(struct pci_dev *dev)
 228{
 229	struct dmar_drhd_unit *drhd;
 230
 231	drhd = dmar_find_matched_drhd_unit(dev);
 232	if (!drhd)
 233		return NULL;
 234
 235	return drhd->iommu;
 236}
 237
 238static int clear_entries(struct irq_2_iommu *irq_iommu)
 239{
 240	struct irte *start, *entry, *end;
 241	struct intel_iommu *iommu;
 242	int index;
 243
 244	if (irq_iommu->sub_handle)
 245		return 0;
 246
 247	iommu = irq_iommu->iommu;
 248	index = irq_iommu->irte_index;
 249
 250	start = iommu->ir_table->base + index;
 251	end = start + (1 << irq_iommu->irte_mask);
 252
 253	for (entry = start; entry < end; entry++) {
 254		set_64bit(&entry->low, 0);
 255		set_64bit(&entry->high, 0);
 256	}
 257	bitmap_release_region(iommu->ir_table->bitmap, index,
 258			      irq_iommu->irte_mask);
 259
 260	return qi_flush_iec(iommu, index, irq_iommu->irte_mask);
 261}
 262
 263/*
 264 * source validation type
 265 */
 266#define SVT_NO_VERIFY		0x0  /* no verification is required */
 267#define SVT_VERIFY_SID_SQ	0x1  /* verify using SID and SQ fields */
 268#define SVT_VERIFY_BUS		0x2  /* verify bus of request-id */
 269
 270/*
 271 * source-id qualifier
 272 */
 273#define SQ_ALL_16	0x0  /* verify all 16 bits of request-id */
 274#define SQ_13_IGNORE_1	0x1  /* verify most significant 13 bits, ignore
 275			      * the third least significant bit
 276			      */
 277#define SQ_13_IGNORE_2	0x2  /* verify most significant 13 bits, ignore
 278			      * the second and third least significant bits
 279			      */
 280#define SQ_13_IGNORE_3	0x3  /* verify most significant 13 bits, ignore
 281			      * the least three significant bits
 282			      */
 283
 284/*
 285 * set SVT, SQ and SID fields of irte to verify
 286 * source ids of interrupt requests
 287 */
 288static void set_irte_sid(struct irte *irte, unsigned int svt,
 289			 unsigned int sq, unsigned int sid)
 290{
 291	if (disable_sourceid_checking)
 292		svt = SVT_NO_VERIFY;
 293	irte->svt = svt;
 294	irte->sq = sq;
 295	irte->sid = sid;
 296}
 297
 298/*
 299 * Set an IRTE to match only the bus number. Interrupt requests that reference
 300 * this IRTE must have a requester-id whose bus number is between or equal
 301 * to the start_bus and end_bus arguments.
 302 */
 303static void set_irte_verify_bus(struct irte *irte, unsigned int start_bus,
 304				unsigned int end_bus)
 305{
 306	set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
 307		     (start_bus << 8) | end_bus);
 308}
 309
 310static int set_ioapic_sid(struct irte *irte, int apic)
 311{
 312	int i;
 313	u16 sid = 0;
 314
 315	if (!irte)
 316		return -1;
 317
 318	down_read(&dmar_global_lock);
 319	for (i = 0; i < MAX_IO_APICS; i++) {
 320		if (ir_ioapic[i].iommu && ir_ioapic[i].id == apic) {
 321			sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn;
 322			break;
 323		}
 324	}
 325	up_read(&dmar_global_lock);
 326
 327	if (sid == 0) {
 328		pr_warn("Failed to set source-id of IOAPIC (%d)\n", apic);
 329		return -1;
 330	}
 331
 332	set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, sid);
 333
 334	return 0;
 335}
 336
 337static int set_hpet_sid(struct irte *irte, u8 id)
 338{
 339	int i;
 340	u16 sid = 0;
 341
 342	if (!irte)
 343		return -1;
 344
 345	down_read(&dmar_global_lock);
 346	for (i = 0; i < MAX_HPET_TBS; i++) {
 347		if (ir_hpet[i].iommu && ir_hpet[i].id == id) {
 348			sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn;
 349			break;
 350		}
 351	}
 352	up_read(&dmar_global_lock);
 353
 354	if (sid == 0) {
 355		pr_warn("Failed to set source-id of HPET block (%d)\n", id);
 356		return -1;
 357	}
 358
 359	/*
 360	 * Should really use SQ_ALL_16. Some platforms are broken.
 361	 * While we figure out the right quirks for these broken platforms, use
 362	 * SQ_13_IGNORE_3 for now.
 363	 */
 364	set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_13_IGNORE_3, sid);
 365
 366	return 0;
 367}
 368
 369struct set_msi_sid_data {
 370	struct pci_dev *pdev;
 371	u16 alias;
 372	int count;
 373	int busmatch_count;
 374};
 375
 376static int set_msi_sid_cb(struct pci_dev *pdev, u16 alias, void *opaque)
 377{
 378	struct set_msi_sid_data *data = opaque;
 379
 380	if (data->count == 0 || PCI_BUS_NUM(alias) == PCI_BUS_NUM(data->alias))
 381		data->busmatch_count++;
 382
 383	data->pdev = pdev;
 384	data->alias = alias;
 385	data->count++;
 386
 387	return 0;
 388}
 389
 390static int set_msi_sid(struct irte *irte, struct pci_dev *dev)
 391{
 392	struct set_msi_sid_data data;
 393
 394	if (!irte || !dev)
 395		return -1;
 396
 397	data.count = 0;
 398	data.busmatch_count = 0;
 399	pci_for_each_dma_alias(dev, set_msi_sid_cb, &data);
 400
 401	/*
 402	 * DMA alias provides us with a PCI device and alias.  The only case
 403	 * where the it will return an alias on a different bus than the
 404	 * device is the case of a PCIe-to-PCI bridge, where the alias is for
 405	 * the subordinate bus.  In this case we can only verify the bus.
 406	 *
 407	 * If there are multiple aliases, all with the same bus number,
 408	 * then all we can do is verify the bus. This is typical in NTB
 409	 * hardware which use proxy IDs where the device will generate traffic
 410	 * from multiple devfn numbers on the same bus.
 411	 *
 412	 * If the alias device is on a different bus than our source device
 413	 * then we have a topology based alias, use it.
 414	 *
 415	 * Otherwise, the alias is for a device DMA quirk and we cannot
 416	 * assume that MSI uses the same requester ID.  Therefore use the
 417	 * original device.
 418	 */
 419	if (PCI_BUS_NUM(data.alias) != data.pdev->bus->number)
 420		set_irte_verify_bus(irte, PCI_BUS_NUM(data.alias),
 421				    dev->bus->number);
 422	else if (data.count >= 2 && data.busmatch_count == data.count)
 423		set_irte_verify_bus(irte, dev->bus->number, dev->bus->number);
 424	else if (data.pdev->bus->number != dev->bus->number)
 425		set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, data.alias);
 426	else
 427		set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
 428			     pci_dev_id(dev));
 429
 430	return 0;
 431}
 432
 433static int iommu_load_old_irte(struct intel_iommu *iommu)
 434{
 435	struct irte *old_ir_table;
 436	phys_addr_t irt_phys;
 437	unsigned int i;
 438	size_t size;
 439	u64 irta;
 440
 441	/* Check whether the old ir-table has the same size as ours */
 442	irta = dmar_readq(iommu->reg + DMAR_IRTA_REG);
 443	if ((irta & INTR_REMAP_TABLE_REG_SIZE_MASK)
 444	     != INTR_REMAP_TABLE_REG_SIZE)
 445		return -EINVAL;
 446
 447	irt_phys = irta & VTD_PAGE_MASK;
 448	size     = INTR_REMAP_TABLE_ENTRIES*sizeof(struct irte);
 449
 450	/* Map the old IR table */
 451	old_ir_table = memremap(irt_phys, size, MEMREMAP_WB);
 452	if (!old_ir_table)
 453		return -ENOMEM;
 454
 455	/* Copy data over */
 456	memcpy(iommu->ir_table->base, old_ir_table, size);
 457
 458	__iommu_flush_cache(iommu, iommu->ir_table->base, size);
 459
 460	/*
 461	 * Now check the table for used entries and mark those as
 462	 * allocated in the bitmap
 463	 */
 464	for (i = 0; i < INTR_REMAP_TABLE_ENTRIES; i++) {
 465		if (iommu->ir_table->base[i].present)
 466			bitmap_set(iommu->ir_table->bitmap, i, 1);
 467	}
 468
 469	memunmap(old_ir_table);
 470
 471	return 0;
 472}
 473
 474
 475static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
 476{
 477	unsigned long flags;
 478	u64 addr;
 479	u32 sts;
 480
 481	addr = virt_to_phys((void *)iommu->ir_table->base);
 482
 483	raw_spin_lock_irqsave(&iommu->register_lock, flags);
 484
 485	dmar_writeq(iommu->reg + DMAR_IRTA_REG,
 486		    (addr) | IR_X2APIC_MODE(mode) | INTR_REMAP_TABLE_REG_SIZE);
 487
 488	/* Set interrupt-remapping table pointer */
 489	writel(iommu->gcmd | DMA_GCMD_SIRTP, iommu->reg + DMAR_GCMD_REG);
 490
 491	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
 492		      readl, (sts & DMA_GSTS_IRTPS), sts);
 493	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 494
 495	/*
 496	 * Global invalidation of interrupt entry cache to make sure the
 497	 * hardware uses the new irq remapping table.
 498	 */
 499	qi_global_iec(iommu);
 500}
 501
 502static void iommu_enable_irq_remapping(struct intel_iommu *iommu)
 503{
 504	unsigned long flags;
 505	u32 sts;
 506
 507	raw_spin_lock_irqsave(&iommu->register_lock, flags);
 508
 509	/* Enable interrupt-remapping */
 510	iommu->gcmd |= DMA_GCMD_IRE;
 511	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
 512	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
 513		      readl, (sts & DMA_GSTS_IRES), sts);
 514
 515	/* Block compatibility-format MSIs */
 516	if (sts & DMA_GSTS_CFIS) {
 517		iommu->gcmd &= ~DMA_GCMD_CFI;
 518		writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
 519		IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
 520			      readl, !(sts & DMA_GSTS_CFIS), sts);
 521	}
 522
 523	/*
 524	 * With CFI clear in the Global Command register, we should be
 525	 * protected from dangerous (i.e. compatibility) interrupts
 526	 * regardless of x2apic status.  Check just to be sure.
 527	 */
 528	if (sts & DMA_GSTS_CFIS)
 529		WARN(1, KERN_WARNING
 530			"Compatibility-format IRQs enabled despite intr remapping;\n"
 531			"you are vulnerable to IRQ injection.\n");
 532
 533	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 534}
 535
 536static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 537{
 538	struct ir_table *ir_table;
 539	struct fwnode_handle *fn;
 540	unsigned long *bitmap;
 541	struct page *pages;
 542
 543	if (iommu->ir_table)
 544		return 0;
 545
 546	ir_table = kzalloc(sizeof(struct ir_table), GFP_KERNEL);
 547	if (!ir_table)
 548		return -ENOMEM;
 549
 550	pages = alloc_pages_node(iommu->node, GFP_KERNEL | __GFP_ZERO,
 551				 INTR_REMAP_PAGE_ORDER);
 552	if (!pages) {
 553		pr_err("IR%d: failed to allocate pages of order %d\n",
 554		       iommu->seq_id, INTR_REMAP_PAGE_ORDER);
 555		goto out_free_table;
 556	}
 557
 558	bitmap = bitmap_zalloc(INTR_REMAP_TABLE_ENTRIES, GFP_ATOMIC);
 559	if (bitmap == NULL) {
 560		pr_err("IR%d: failed to allocate bitmap\n", iommu->seq_id);
 561		goto out_free_pages;
 562	}
 563
 564	fn = irq_domain_alloc_named_id_fwnode("INTEL-IR", iommu->seq_id);
 565	if (!fn)
 566		goto out_free_bitmap;
 567
 568	iommu->ir_domain =
 569		irq_domain_create_hierarchy(arch_get_ir_parent_domain(),
 570					    0, INTR_REMAP_TABLE_ENTRIES,
 571					    fn, &intel_ir_domain_ops,
 572					    iommu);
 573	if (!iommu->ir_domain) {
 574		irq_domain_free_fwnode(fn);
 575		pr_err("IR%d: failed to allocate irqdomain\n", iommu->seq_id);
 576		goto out_free_bitmap;
 577	}
 578	iommu->ir_msi_domain =
 579		arch_create_remap_msi_irq_domain(iommu->ir_domain,
 580						 "INTEL-IR-MSI",
 581						 iommu->seq_id);
 582
 583	ir_table->base = page_address(pages);
 584	ir_table->bitmap = bitmap;
 585	iommu->ir_table = ir_table;
 586
 587	/*
 588	 * If the queued invalidation is already initialized,
 589	 * shouldn't disable it.
 590	 */
 591	if (!iommu->qi) {
 592		/*
 593		 * Clear previous faults.
 594		 */
 595		dmar_fault(-1, iommu);
 596		dmar_disable_qi(iommu);
 597
 598		if (dmar_enable_qi(iommu)) {
 599			pr_err("Failed to enable queued invalidation\n");
 600			goto out_free_bitmap;
 601		}
 602	}
 603
 604	init_ir_status(iommu);
 605
 606	if (ir_pre_enabled(iommu)) {
 607		if (!is_kdump_kernel()) {
 608			pr_warn("IRQ remapping was enabled on %s but we are not in kdump mode\n",
 609				iommu->name);
 610			clear_ir_pre_enabled(iommu);
 611			iommu_disable_irq_remapping(iommu);
 612		} else if (iommu_load_old_irte(iommu))
 613			pr_err("Failed to copy IR table for %s from previous kernel\n",
 614			       iommu->name);
 615		else
 616			pr_info("Copied IR table for %s from previous kernel\n",
 617				iommu->name);
 618	}
 619
 620	iommu_set_irq_remapping(iommu, eim_mode);
 621
 622	return 0;
 623
 624out_free_bitmap:
 625	bitmap_free(bitmap);
 626out_free_pages:
 627	__free_pages(pages, INTR_REMAP_PAGE_ORDER);
 628out_free_table:
 629	kfree(ir_table);
 630
 631	iommu->ir_table  = NULL;
 632
 633	return -ENOMEM;
 634}
 635
 636static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
 637{
 638	struct fwnode_handle *fn;
 639
 640	if (iommu && iommu->ir_table) {
 641		if (iommu->ir_msi_domain) {
 642			fn = iommu->ir_msi_domain->fwnode;
 643
 644			irq_domain_remove(iommu->ir_msi_domain);
 645			irq_domain_free_fwnode(fn);
 646			iommu->ir_msi_domain = NULL;
 647		}
 648		if (iommu->ir_domain) {
 649			fn = iommu->ir_domain->fwnode;
 650
 651			irq_domain_remove(iommu->ir_domain);
 652			irq_domain_free_fwnode(fn);
 653			iommu->ir_domain = NULL;
 654		}
 655		free_pages((unsigned long)iommu->ir_table->base,
 656			   INTR_REMAP_PAGE_ORDER);
 657		bitmap_free(iommu->ir_table->bitmap);
 658		kfree(iommu->ir_table);
 659		iommu->ir_table = NULL;
 660	}
 661}
 662
 663/*
 664 * Disable Interrupt Remapping.
 665 */
 666static void iommu_disable_irq_remapping(struct intel_iommu *iommu)
 667{
 668	unsigned long flags;
 669	u32 sts;
 670
 671	if (!ecap_ir_support(iommu->ecap))
 672		return;
 673
 674	/*
 675	 * global invalidation of interrupt entry cache before disabling
 676	 * interrupt-remapping.
 677	 */
 678	qi_global_iec(iommu);
 679
 680	raw_spin_lock_irqsave(&iommu->register_lock, flags);
 681
 682	sts = readl(iommu->reg + DMAR_GSTS_REG);
 683	if (!(sts & DMA_GSTS_IRES))
 684		goto end;
 685
 686	iommu->gcmd &= ~DMA_GCMD_IRE;
 687	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
 688
 689	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
 690		      readl, !(sts & DMA_GSTS_IRES), sts);
 691
 692end:
 693	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 694}
 695
 696static int __init dmar_x2apic_optout(void)
 697{
 698	struct acpi_table_dmar *dmar;
 699	dmar = (struct acpi_table_dmar *)dmar_tbl;
 700	if (!dmar || no_x2apic_optout)
 701		return 0;
 702	return dmar->flags & DMAR_X2APIC_OPT_OUT;
 703}
 704
 705static void __init intel_cleanup_irq_remapping(void)
 706{
 707	struct dmar_drhd_unit *drhd;
 708	struct intel_iommu *iommu;
 709
 710	for_each_iommu(iommu, drhd) {
 711		if (ecap_ir_support(iommu->ecap)) {
 712			iommu_disable_irq_remapping(iommu);
 713			intel_teardown_irq_remapping(iommu);
 714		}
 715	}
 716
 717	if (x2apic_supported())
 718		pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n");
 719}
 720
 721static int __init intel_prepare_irq_remapping(void)
 722{
 723	struct dmar_drhd_unit *drhd;
 724	struct intel_iommu *iommu;
 725	int eim = 0;
 726
 727	if (irq_remap_broken) {
 728		pr_warn("This system BIOS has enabled interrupt remapping\n"
 729			"on a chipset that contains an erratum making that\n"
 730			"feature unstable.  To maintain system stability\n"
 731			"interrupt remapping is being disabled.  Please\n"
 732			"contact your BIOS vendor for an update\n");
 733		add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
 734		return -ENODEV;
 735	}
 736
 737	if (dmar_table_init() < 0)
 738		return -ENODEV;
 739
 740	if (!dmar_ir_support())
 741		return -ENODEV;
 742
 743	if (parse_ioapics_under_ir()) {
 744		pr_info("Not enabling interrupt remapping\n");
 745		goto error;
 746	}
 747
 748	/* First make sure all IOMMUs support IRQ remapping */
 749	for_each_iommu(iommu, drhd)
 750		if (!ecap_ir_support(iommu->ecap))
 751			goto error;
 752
 753	/* Detect remapping mode: lapic or x2apic */
 754	if (x2apic_supported()) {
 755		eim = !dmar_x2apic_optout();
 756		if (!eim) {
 757			pr_info("x2apic is disabled because BIOS sets x2apic opt out bit.");
 758			pr_info("Use 'intremap=no_x2apic_optout' to override the BIOS setting.\n");
 759		}
 760	}
 761
 762	for_each_iommu(iommu, drhd) {
 763		if (eim && !ecap_eim_support(iommu->ecap)) {
 764			pr_info("%s does not support EIM\n", iommu->name);
 765			eim = 0;
 766		}
 767	}
 768
 769	eim_mode = eim;
 770	if (eim)
 771		pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n");
 772
 773	/* Do the initializations early */
 774	for_each_iommu(iommu, drhd) {
 775		if (intel_setup_irq_remapping(iommu)) {
 776			pr_err("Failed to setup irq remapping for %s\n",
 777			       iommu->name);
 778			goto error;
 779		}
 780	}
 781
 782	return 0;
 783
 784error:
 785	intel_cleanup_irq_remapping();
 786	return -ENODEV;
 787}
 788
 789/*
 790 * Set Posted-Interrupts capability.
 791 */
 792static inline void set_irq_posting_cap(void)
 793{
 794	struct dmar_drhd_unit *drhd;
 795	struct intel_iommu *iommu;
 796
 797	if (!disable_irq_post) {
 798		/*
 799		 * If IRTE is in posted format, the 'pda' field goes across the
 800		 * 64-bit boundary, we need use cmpxchg16b to atomically update
 801		 * it. We only expose posted-interrupt when X86_FEATURE_CX16
 802		 * is supported. Actually, hardware platforms supporting PI
 803		 * should have X86_FEATURE_CX16 support, this has been confirmed
 804		 * with Intel hardware guys.
 805		 */
 806		if (boot_cpu_has(X86_FEATURE_CX16))
 807			intel_irq_remap_ops.capability |= 1 << IRQ_POSTING_CAP;
 808
 809		for_each_iommu(iommu, drhd)
 810			if (!cap_pi_support(iommu->cap)) {
 811				intel_irq_remap_ops.capability &=
 812						~(1 << IRQ_POSTING_CAP);
 813				break;
 814			}
 815	}
 816}
 817
 818static int __init intel_enable_irq_remapping(void)
 819{
 820	struct dmar_drhd_unit *drhd;
 821	struct intel_iommu *iommu;
 822	bool setup = false;
 823
 824	/*
 825	 * Setup Interrupt-remapping for all the DRHD's now.
 826	 */
 827	for_each_iommu(iommu, drhd) {
 828		if (!ir_pre_enabled(iommu))
 829			iommu_enable_irq_remapping(iommu);
 830		setup = true;
 831	}
 832
 833	if (!setup)
 834		goto error;
 835
 836	irq_remapping_enabled = 1;
 837
 838	set_irq_posting_cap();
 839
 840	pr_info("Enabled IRQ remapping in %s mode\n", eim_mode ? "x2apic" : "xapic");
 841
 842	return eim_mode ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
 843
 844error:
 845	intel_cleanup_irq_remapping();
 846	return -1;
 847}
 848
 849static int ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope,
 850				   struct intel_iommu *iommu,
 851				   struct acpi_dmar_hardware_unit *drhd)
 852{
 853	struct acpi_dmar_pci_path *path;
 854	u8 bus;
 855	int count, free = -1;
 856
 857	bus = scope->bus;
 858	path = (struct acpi_dmar_pci_path *)(scope + 1);
 859	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
 860		/ sizeof(struct acpi_dmar_pci_path);
 861
 862	while (--count > 0) {
 863		/*
 864		 * Access PCI directly due to the PCI
 865		 * subsystem isn't initialized yet.
 866		 */
 867		bus = read_pci_config_byte(bus, path->device, path->function,
 868					   PCI_SECONDARY_BUS);
 869		path++;
 870	}
 871
 872	for (count = 0; count < MAX_HPET_TBS; count++) {
 873		if (ir_hpet[count].iommu == iommu &&
 874		    ir_hpet[count].id == scope->enumeration_id)
 875			return 0;
 876		else if (ir_hpet[count].iommu == NULL && free == -1)
 877			free = count;
 878	}
 879	if (free == -1) {
 880		pr_warn("Exceeded Max HPET blocks\n");
 881		return -ENOSPC;
 882	}
 883
 884	ir_hpet[free].iommu = iommu;
 885	ir_hpet[free].id    = scope->enumeration_id;
 886	ir_hpet[free].bus   = bus;
 887	ir_hpet[free].devfn = PCI_DEVFN(path->device, path->function);
 888	pr_info("HPET id %d under DRHD base 0x%Lx\n",
 889		scope->enumeration_id, drhd->address);
 890
 891	return 0;
 892}
 893
 894static int ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
 895				     struct intel_iommu *iommu,
 896				     struct acpi_dmar_hardware_unit *drhd)
 897{
 898	struct acpi_dmar_pci_path *path;
 899	u8 bus;
 900	int count, free = -1;
 901
 902	bus = scope->bus;
 903	path = (struct acpi_dmar_pci_path *)(scope + 1);
 904	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
 905		/ sizeof(struct acpi_dmar_pci_path);
 906
 907	while (--count > 0) {
 908		/*
 909		 * Access PCI directly due to the PCI
 910		 * subsystem isn't initialized yet.
 911		 */
 912		bus = read_pci_config_byte(bus, path->device, path->function,
 913					   PCI_SECONDARY_BUS);
 914		path++;
 915	}
 916
 917	for (count = 0; count < MAX_IO_APICS; count++) {
 918		if (ir_ioapic[count].iommu == iommu &&
 919		    ir_ioapic[count].id == scope->enumeration_id)
 920			return 0;
 921		else if (ir_ioapic[count].iommu == NULL && free == -1)
 922			free = count;
 923	}
 924	if (free == -1) {
 925		pr_warn("Exceeded Max IO APICS\n");
 926		return -ENOSPC;
 927	}
 928
 929	ir_ioapic[free].bus   = bus;
 930	ir_ioapic[free].devfn = PCI_DEVFN(path->device, path->function);
 931	ir_ioapic[free].iommu = iommu;
 932	ir_ioapic[free].id    = scope->enumeration_id;
 933	pr_info("IOAPIC id %d under DRHD base  0x%Lx IOMMU %d\n",
 934		scope->enumeration_id, drhd->address, iommu->seq_id);
 935
 936	return 0;
 937}
 938
 939static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_header *header,
 940				      struct intel_iommu *iommu)
 941{
 942	int ret = 0;
 943	struct acpi_dmar_hardware_unit *drhd;
 944	struct acpi_dmar_device_scope *scope;
 945	void *start, *end;
 946
 947	drhd = (struct acpi_dmar_hardware_unit *)header;
 948	start = (void *)(drhd + 1);
 949	end = ((void *)drhd) + header->length;
 950
 951	while (start < end && ret == 0) {
 952		scope = start;
 953		if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC)
 954			ret = ir_parse_one_ioapic_scope(scope, iommu, drhd);
 955		else if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_HPET)
 956			ret = ir_parse_one_hpet_scope(scope, iommu, drhd);
 957		start += scope->length;
 958	}
 959
 960	return ret;
 961}
 962
 963static void ir_remove_ioapic_hpet_scope(struct intel_iommu *iommu)
 964{
 965	int i;
 966
 967	for (i = 0; i < MAX_HPET_TBS; i++)
 968		if (ir_hpet[i].iommu == iommu)
 969			ir_hpet[i].iommu = NULL;
 970
 971	for (i = 0; i < MAX_IO_APICS; i++)
 972		if (ir_ioapic[i].iommu == iommu)
 973			ir_ioapic[i].iommu = NULL;
 974}
 975
 976/*
 977 * Finds the assocaition between IOAPIC's and its Interrupt-remapping
 978 * hardware unit.
 979 */
 980static int __init parse_ioapics_under_ir(void)
 981{
 982	struct dmar_drhd_unit *drhd;
 983	struct intel_iommu *iommu;
 984	bool ir_supported = false;
 985	int ioapic_idx;
 986
 987	for_each_iommu(iommu, drhd) {
 988		int ret;
 989
 990		if (!ecap_ir_support(iommu->ecap))
 991			continue;
 992
 993		ret = ir_parse_ioapic_hpet_scope(drhd->hdr, iommu);
 994		if (ret)
 995			return ret;
 996
 997		ir_supported = true;
 998	}
 999
1000	if (!ir_supported)
1001		return -ENODEV;
1002
1003	for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) {
1004		int ioapic_id = mpc_ioapic_id(ioapic_idx);
1005		if (!map_ioapic_to_ir(ioapic_id)) {
1006			pr_err(FW_BUG "ioapic %d has no mapping iommu, "
1007			       "interrupt remapping will be disabled\n",
1008			       ioapic_id);
1009			return -1;
1010		}
1011	}
1012
1013	return 0;
1014}
1015
1016static int __init ir_dev_scope_init(void)
1017{
1018	int ret;
1019
1020	if (!irq_remapping_enabled)
1021		return 0;
1022
1023	down_write(&dmar_global_lock);
1024	ret = dmar_dev_scope_init();
1025	up_write(&dmar_global_lock);
1026
1027	return ret;
1028}
1029rootfs_initcall(ir_dev_scope_init);
1030
1031static void disable_irq_remapping(void)
1032{
1033	struct dmar_drhd_unit *drhd;
1034	struct intel_iommu *iommu = NULL;
1035
1036	/*
1037	 * Disable Interrupt-remapping for all the DRHD's now.
1038	 */
1039	for_each_iommu(iommu, drhd) {
1040		if (!ecap_ir_support(iommu->ecap))
1041			continue;
1042
1043		iommu_disable_irq_remapping(iommu);
1044	}
1045
1046	/*
1047	 * Clear Posted-Interrupts capability.
1048	 */
1049	if (!disable_irq_post)
1050		intel_irq_remap_ops.capability &= ~(1 << IRQ_POSTING_CAP);
1051}
1052
1053static int reenable_irq_remapping(int eim)
1054{
1055	struct dmar_drhd_unit *drhd;
1056	bool setup = false;
1057	struct intel_iommu *iommu = NULL;
1058
1059	for_each_iommu(iommu, drhd)
1060		if (iommu->qi)
1061			dmar_reenable_qi(iommu);
1062
1063	/*
1064	 * Setup Interrupt-remapping for all the DRHD's now.
1065	 */
1066	for_each_iommu(iommu, drhd) {
1067		if (!ecap_ir_support(iommu->ecap))
1068			continue;
1069
1070		/* Set up interrupt remapping for iommu.*/
1071		iommu_set_irq_remapping(iommu, eim);
1072		iommu_enable_irq_remapping(iommu);
1073		setup = true;
1074	}
1075
1076	if (!setup)
1077		goto error;
1078
1079	set_irq_posting_cap();
1080
1081	return 0;
1082
1083error:
1084	/*
1085	 * handle error condition gracefully here!
1086	 */
1087	return -1;
1088}
1089
1090static void prepare_irte(struct irte *irte, int vector, unsigned int dest)
1091{
1092	memset(irte, 0, sizeof(*irte));
1093
1094	irte->present = 1;
1095	irte->dst_mode = apic->irq_dest_mode;
1096	/*
1097	 * Trigger mode in the IRTE will always be edge, and for IO-APIC, the
1098	 * actual level or edge trigger will be setup in the IO-APIC
1099	 * RTE. This will help simplify level triggered irq migration.
1100	 * For more details, see the comments (in io_apic.c) explainig IO-APIC
1101	 * irq migration in the presence of interrupt-remapping.
1102	*/
1103	irte->trigger_mode = 0;
1104	irte->dlvry_mode = apic->irq_delivery_mode;
1105	irte->vector = vector;
1106	irte->dest_id = IRTE_DEST(dest);
1107	irte->redir_hint = 1;
1108}
1109
1110static struct irq_domain *intel_get_ir_irq_domain(struct irq_alloc_info *info)
1111{
1112	struct intel_iommu *iommu = NULL;
1113
1114	if (!info)
1115		return NULL;
1116
1117	switch (info->type) {
1118	case X86_IRQ_ALLOC_TYPE_IOAPIC:
1119		iommu = map_ioapic_to_ir(info->ioapic_id);
1120		break;
1121	case X86_IRQ_ALLOC_TYPE_HPET:
1122		iommu = map_hpet_to_ir(info->hpet_id);
1123		break;
1124	case X86_IRQ_ALLOC_TYPE_MSI:
1125	case X86_IRQ_ALLOC_TYPE_MSIX:
1126		iommu = map_dev_to_ir(info->msi_dev);
1127		break;
1128	default:
1129		BUG_ON(1);
1130		break;
1131	}
1132
1133	return iommu ? iommu->ir_domain : NULL;
1134}
1135
1136static struct irq_domain *intel_get_irq_domain(struct irq_alloc_info *info)
1137{
1138	struct intel_iommu *iommu;
1139
1140	if (!info)
1141		return NULL;
1142
1143	switch (info->type) {
1144	case X86_IRQ_ALLOC_TYPE_MSI:
1145	case X86_IRQ_ALLOC_TYPE_MSIX:
1146		iommu = map_dev_to_ir(info->msi_dev);
1147		if (iommu)
1148			return iommu->ir_msi_domain;
1149		break;
1150	default:
1151		break;
1152	}
1153
1154	return NULL;
1155}
1156
1157struct irq_remap_ops intel_irq_remap_ops = {
1158	.prepare		= intel_prepare_irq_remapping,
1159	.enable			= intel_enable_irq_remapping,
1160	.disable		= disable_irq_remapping,
1161	.reenable		= reenable_irq_remapping,
1162	.enable_faulting	= enable_drhd_fault_handling,
1163	.get_ir_irq_domain	= intel_get_ir_irq_domain,
1164	.get_irq_domain		= intel_get_irq_domain,
1165};
1166
1167static void intel_ir_reconfigure_irte(struct irq_data *irqd, bool force)
1168{
1169	struct intel_ir_data *ir_data = irqd->chip_data;
1170	struct irte *irte = &ir_data->irte_entry;
1171	struct irq_cfg *cfg = irqd_cfg(irqd);
1172
1173	/*
1174	 * Atomically updates the IRTE with the new destination, vector
1175	 * and flushes the interrupt entry cache.
1176	 */
1177	irte->vector = cfg->vector;
1178	irte->dest_id = IRTE_DEST(cfg->dest_apicid);
1179
1180	/* Update the hardware only if the interrupt is in remapped mode. */
1181	if (force || ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
1182		modify_irte(&ir_data->irq_2_iommu, irte);
1183}
1184
1185/*
1186 * Migrate the IO-APIC irq in the presence of intr-remapping.
1187 *
1188 * For both level and edge triggered, irq migration is a simple atomic
1189 * update(of vector and cpu destination) of IRTE and flush the hardware cache.
1190 *
1191 * For level triggered, we eliminate the io-apic RTE modification (with the
1192 * updated vector information), by using a virtual vector (io-apic pin number).
1193 * Real vector that is used for interrupting cpu will be coming from
1194 * the interrupt-remapping table entry.
1195 *
1196 * As the migration is a simple atomic update of IRTE, the same mechanism
1197 * is used to migrate MSI irq's in the presence of interrupt-remapping.
1198 */
1199static int
1200intel_ir_set_affinity(struct irq_data *data, const struct cpumask *mask,
1201		      bool force)
1202{
1203	struct irq_data *parent = data->parent_data;
1204	struct irq_cfg *cfg = irqd_cfg(data);
1205	int ret;
1206
1207	ret = parent->chip->irq_set_affinity(parent, mask, force);
1208	if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
1209		return ret;
1210
1211	intel_ir_reconfigure_irte(data, false);
1212	/*
1213	 * After this point, all the interrupts will start arriving
1214	 * at the new destination. So, time to cleanup the previous
1215	 * vector allocation.
1216	 */
1217	send_cleanup_vector(cfg);
1218
1219	return IRQ_SET_MASK_OK_DONE;
1220}
1221
1222static void intel_ir_compose_msi_msg(struct irq_data *irq_data,
1223				     struct msi_msg *msg)
1224{
1225	struct intel_ir_data *ir_data = irq_data->chip_data;
1226
1227	*msg = ir_data->msi_entry;
1228}
1229
1230static int intel_ir_set_vcpu_affinity(struct irq_data *data, void *info)
1231{
1232	struct intel_ir_data *ir_data = data->chip_data;
1233	struct vcpu_data *vcpu_pi_info = info;
1234
1235	/* stop posting interrupts, back to remapping mode */
1236	if (!vcpu_pi_info) {
1237		modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry);
1238	} else {
1239		struct irte irte_pi;
1240
1241		/*
1242		 * We are not caching the posted interrupt entry. We
1243		 * copy the data from the remapped entry and modify
1244		 * the fields which are relevant for posted mode. The
1245		 * cached remapped entry is used for switching back to
1246		 * remapped mode.
1247		 */
1248		memset(&irte_pi, 0, sizeof(irte_pi));
1249		dmar_copy_shared_irte(&irte_pi, &ir_data->irte_entry);
1250
1251		/* Update the posted mode fields */
1252		irte_pi.p_pst = 1;
1253		irte_pi.p_urgent = 0;
1254		irte_pi.p_vector = vcpu_pi_info->vector;
1255		irte_pi.pda_l = (vcpu_pi_info->pi_desc_addr >>
1256				(32 - PDA_LOW_BIT)) & ~(-1UL << PDA_LOW_BIT);
1257		irte_pi.pda_h = (vcpu_pi_info->pi_desc_addr >> 32) &
1258				~(-1UL << PDA_HIGH_BIT);
1259
1260		modify_irte(&ir_data->irq_2_iommu, &irte_pi);
1261	}
1262
1263	return 0;
1264}
1265
1266static struct irq_chip intel_ir_chip = {
1267	.name			= "INTEL-IR",
1268	.irq_ack		= apic_ack_irq,
1269	.irq_set_affinity	= intel_ir_set_affinity,
1270	.irq_compose_msi_msg	= intel_ir_compose_msi_msg,
1271	.irq_set_vcpu_affinity	= intel_ir_set_vcpu_affinity,
1272};
1273
1274static void intel_irq_remapping_prepare_irte(struct intel_ir_data *data,
1275					     struct irq_cfg *irq_cfg,
1276					     struct irq_alloc_info *info,
1277					     int index, int sub_handle)
1278{
1279	struct IR_IO_APIC_route_entry *entry;
1280	struct irte *irte = &data->irte_entry;
1281	struct msi_msg *msg = &data->msi_entry;
1282
1283	prepare_irte(irte, irq_cfg->vector, irq_cfg->dest_apicid);
1284	switch (info->type) {
1285	case X86_IRQ_ALLOC_TYPE_IOAPIC:
1286		/* Set source-id of interrupt request */
1287		set_ioapic_sid(irte, info->ioapic_id);
1288		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",
1289			info->ioapic_id, irte->present, irte->fpd,
1290			irte->dst_mode, irte->redir_hint,
1291			irte->trigger_mode, irte->dlvry_mode,
1292			irte->avail, irte->vector, irte->dest_id,
1293			irte->sid, irte->sq, irte->svt);
1294
1295		entry = (struct IR_IO_APIC_route_entry *)info->ioapic_entry;
1296		info->ioapic_entry = NULL;
1297		memset(entry, 0, sizeof(*entry));
1298		entry->index2	= (index >> 15) & 0x1;
1299		entry->zero	= 0;
1300		entry->format	= 1;
1301		entry->index	= (index & 0x7fff);
1302		/*
1303		 * IO-APIC RTE will be configured with virtual vector.
1304		 * irq handler will do the explicit EOI to the io-apic.
1305		 */
1306		entry->vector	= info->ioapic_pin;
1307		entry->mask	= 0;			/* enable IRQ */
1308		entry->trigger	= info->ioapic_trigger;
1309		entry->polarity	= info->ioapic_polarity;
1310		if (info->ioapic_trigger)
1311			entry->mask = 1; /* Mask level triggered irqs. */
1312		break;
1313
1314	case X86_IRQ_ALLOC_TYPE_HPET:
1315	case X86_IRQ_ALLOC_TYPE_MSI:
1316	case X86_IRQ_ALLOC_TYPE_MSIX:
1317		if (info->type == X86_IRQ_ALLOC_TYPE_HPET)
1318			set_hpet_sid(irte, info->hpet_id);
1319		else
1320			set_msi_sid(irte, info->msi_dev);
1321
1322		msg->address_hi = MSI_ADDR_BASE_HI;
1323		msg->data = sub_handle;
1324		msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT |
1325				  MSI_ADDR_IR_SHV |
1326				  MSI_ADDR_IR_INDEX1(index) |
1327				  MSI_ADDR_IR_INDEX2(index);
1328		break;
1329
1330	default:
1331		BUG_ON(1);
1332		break;
1333	}
1334}
1335
1336static void intel_free_irq_resources(struct irq_domain *domain,
1337				     unsigned int virq, unsigned int nr_irqs)
1338{
1339	struct irq_data *irq_data;
1340	struct intel_ir_data *data;
1341	struct irq_2_iommu *irq_iommu;
1342	unsigned long flags;
1343	int i;
1344	for (i = 0; i < nr_irqs; i++) {
1345		irq_data = irq_domain_get_irq_data(domain, virq  + i);
1346		if (irq_data && irq_data->chip_data) {
1347			data = irq_data->chip_data;
1348			irq_iommu = &data->irq_2_iommu;
1349			raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
1350			clear_entries(irq_iommu);
1351			raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
1352			irq_domain_reset_irq_data(irq_data);
1353			kfree(data);
1354		}
1355	}
1356}
1357
1358static int intel_irq_remapping_alloc(struct irq_domain *domain,
1359				     unsigned int virq, unsigned int nr_irqs,
1360				     void *arg)
1361{
1362	struct intel_iommu *iommu = domain->host_data;
1363	struct irq_alloc_info *info = arg;
1364	struct intel_ir_data *data, *ird;
1365	struct irq_data *irq_data;
1366	struct irq_cfg *irq_cfg;
1367	int i, ret, index;
1368
1369	if (!info || !iommu)
1370		return -EINVAL;
1371	if (nr_irqs > 1 && info->type != X86_IRQ_ALLOC_TYPE_MSI &&
1372	    info->type != X86_IRQ_ALLOC_TYPE_MSIX)
1373		return -EINVAL;
1374
1375	/*
1376	 * With IRQ remapping enabled, don't need contiguous CPU vectors
1377	 * to support multiple MSI interrupts.
1378	 */
1379	if (info->type == X86_IRQ_ALLOC_TYPE_MSI)
1380		info->flags &= ~X86_IRQ_ALLOC_CONTIGUOUS_VECTORS;
1381
1382	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
1383	if (ret < 0)
1384		return ret;
1385
1386	ret = -ENOMEM;
1387	data = kzalloc(sizeof(*data), GFP_KERNEL);
1388	if (!data)
1389		goto out_free_parent;
1390
1391	down_read(&dmar_global_lock);
1392	index = alloc_irte(iommu, &data->irq_2_iommu, nr_irqs);
1393	up_read(&dmar_global_lock);
1394	if (index < 0) {
1395		pr_warn("Failed to allocate IRTE\n");
1396		kfree(data);
1397		goto out_free_parent;
1398	}
1399
1400	for (i = 0; i < nr_irqs; i++) {
1401		irq_data = irq_domain_get_irq_data(domain, virq + i);
1402		irq_cfg = irqd_cfg(irq_data);
1403		if (!irq_data || !irq_cfg) {
1404			ret = -EINVAL;
1405			goto out_free_data;
1406		}
1407
1408		if (i > 0) {
1409			ird = kzalloc(sizeof(*ird), GFP_KERNEL);
1410			if (!ird)
1411				goto out_free_data;
1412			/* Initialize the common data */
1413			ird->irq_2_iommu = data->irq_2_iommu;
1414			ird->irq_2_iommu.sub_handle = i;
1415		} else {
1416			ird = data;
1417		}
1418
1419		irq_data->hwirq = (index << 16) + i;
1420		irq_data->chip_data = ird;
1421		irq_data->chip = &intel_ir_chip;
1422		intel_irq_remapping_prepare_irte(ird, irq_cfg, info, index, i);
1423		irq_set_status_flags(virq + i, IRQ_MOVE_PCNTXT);
1424	}
1425	return 0;
1426
1427out_free_data:
1428	intel_free_irq_resources(domain, virq, i);
1429out_free_parent:
1430	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1431	return ret;
1432}
1433
1434static void intel_irq_remapping_free(struct irq_domain *domain,
1435				     unsigned int virq, unsigned int nr_irqs)
1436{
1437	intel_free_irq_resources(domain, virq, nr_irqs);
1438	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1439}
1440
1441static int intel_irq_remapping_activate(struct irq_domain *domain,
1442					struct irq_data *irq_data, bool reserve)
1443{
1444	intel_ir_reconfigure_irte(irq_data, true);
1445	return 0;
1446}
1447
1448static void intel_irq_remapping_deactivate(struct irq_domain *domain,
1449					   struct irq_data *irq_data)
1450{
1451	struct intel_ir_data *data = irq_data->chip_data;
1452	struct irte entry;
1453
1454	memset(&entry, 0, sizeof(entry));
1455	modify_irte(&data->irq_2_iommu, &entry);
1456}
1457
1458static const struct irq_domain_ops intel_ir_domain_ops = {
1459	.alloc = intel_irq_remapping_alloc,
1460	.free = intel_irq_remapping_free,
1461	.activate = intel_irq_remapping_activate,
1462	.deactivate = intel_irq_remapping_deactivate,
1463};
1464
1465/*
1466 * Support of Interrupt Remapping Unit Hotplug
1467 */
1468static int dmar_ir_add(struct dmar_drhd_unit *dmaru, struct intel_iommu *iommu)
1469{
1470	int ret;
1471	int eim = x2apic_enabled();
1472
1473	if (eim && !ecap_eim_support(iommu->ecap)) {
1474		pr_info("DRHD %Lx: EIM not supported by DRHD, ecap %Lx\n",
1475			iommu->reg_phys, iommu->ecap);
1476		return -ENODEV;
1477	}
1478
1479	if (ir_parse_ioapic_hpet_scope(dmaru->hdr, iommu)) {
1480		pr_warn("DRHD %Lx: failed to parse managed IOAPIC/HPET\n",
1481			iommu->reg_phys);
1482		return -ENODEV;
1483	}
1484
1485	/* TODO: check all IOAPICs are covered by IOMMU */
1486
1487	/* Setup Interrupt-remapping now. */
1488	ret = intel_setup_irq_remapping(iommu);
1489	if (ret) {
1490		pr_err("Failed to setup irq remapping for %s\n",
1491		       iommu->name);
1492		intel_teardown_irq_remapping(iommu);
1493		ir_remove_ioapic_hpet_scope(iommu);
1494	} else {
1495		iommu_enable_irq_remapping(iommu);
1496	}
1497
1498	return ret;
1499}
1500
1501int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert)
1502{
1503	int ret = 0;
1504	struct intel_iommu *iommu = dmaru->iommu;
1505
1506	if (!irq_remapping_enabled)
1507		return 0;
1508	if (iommu == NULL)
1509		return -EINVAL;
1510	if (!ecap_ir_support(iommu->ecap))
1511		return 0;
1512	if (irq_remapping_cap(IRQ_POSTING_CAP) &&
1513	    !cap_pi_support(iommu->cap))
1514		return -EBUSY;
1515
1516	if (insert) {
1517		if (!iommu->ir_table)
1518			ret = dmar_ir_add(dmaru, iommu);
1519	} else {
1520		if (iommu->ir_table) {
1521			if (!bitmap_empty(iommu->ir_table->bitmap,
1522					  INTR_REMAP_TABLE_ENTRIES)) {
1523				ret = -EBUSY;
1524			} else {
1525				iommu_disable_irq_remapping(iommu);
1526				intel_teardown_irq_remapping(iommu);
1527				ir_remove_ioapic_hpet_scope(iommu);
1528			}
1529		}
1530	}
1531
1532	return ret;
1533}