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   1
   2#define pr_fmt(fmt)     "DMAR-IR: " fmt
   3
   4#include <linux/interrupt.h>
   5#include <linux/dmar.h>
   6#include <linux/spinlock.h>
   7#include <linux/slab.h>
   8#include <linux/jiffies.h>
   9#include <linux/hpet.h>
  10#include <linux/pci.h>
  11#include <linux/irq.h>
  12#include <linux/intel-iommu.h>
  13#include <linux/acpi.h>
  14#include <linux/irqdomain.h>
  15#include <linux/crash_dump.h>
  16#include <asm/io_apic.h>
  17#include <asm/smp.h>
  18#include <asm/cpu.h>
  19#include <asm/irq_remapping.h>
  20#include <asm/pci-direct.h>
  21#include <asm/msidef.h>
  22
  23#include "irq_remapping.h"
  24
  25enum irq_mode {
  26	IRQ_REMAPPING,
  27	IRQ_POSTING,
  28};
  29
  30struct ioapic_scope {
  31	struct intel_iommu *iommu;
  32	unsigned int id;
  33	unsigned int bus;	/* PCI bus number */
  34	unsigned int devfn;	/* PCI devfn number */
  35};
  36
  37struct hpet_scope {
  38	struct intel_iommu *iommu;
  39	u8 id;
  40	unsigned int bus;
  41	unsigned int devfn;
  42};
  43
  44struct irq_2_iommu {
  45	struct intel_iommu *iommu;
  46	u16 irte_index;
  47	u16 sub_handle;
  48	u8  irte_mask;
  49	enum irq_mode mode;
  50};
  51
  52struct intel_ir_data {
  53	struct irq_2_iommu			irq_2_iommu;
  54	struct irte				irte_entry;
  55	union {
  56		struct msi_msg			msi_entry;
  57	};
  58};
  59
  60#define IR_X2APIC_MODE(mode) (mode ? (1 << 11) : 0)
  61#define IRTE_DEST(dest) ((eim_mode) ? dest : dest << 8)
  62
  63static int __read_mostly eim_mode;
  64static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
  65static struct hpet_scope ir_hpet[MAX_HPET_TBS];
  66
  67/*
  68 * Lock ordering:
  69 * ->dmar_global_lock
  70 *	->irq_2_ir_lock
  71 *		->qi->q_lock
  72 *	->iommu->register_lock
  73 * Note:
  74 * intel_irq_remap_ops.{supported,prepare,enable,disable,reenable} are called
  75 * in single-threaded environment with interrupt disabled, so no need to tabke
  76 * the dmar_global_lock.
  77 */
  78static DEFINE_RAW_SPINLOCK(irq_2_ir_lock);
  79static struct irq_domain_ops intel_ir_domain_ops;
  80
  81static void iommu_disable_irq_remapping(struct intel_iommu *iommu);
  82static int __init parse_ioapics_under_ir(void);
  83
  84static bool ir_pre_enabled(struct intel_iommu *iommu)
  85{
  86	return (iommu->flags & VTD_FLAG_IRQ_REMAP_PRE_ENABLED);
  87}
  88
  89static void clear_ir_pre_enabled(struct intel_iommu *iommu)
  90{
  91	iommu->flags &= ~VTD_FLAG_IRQ_REMAP_PRE_ENABLED;
  92}
  93
  94static void init_ir_status(struct intel_iommu *iommu)
  95{
  96	u32 gsts;
  97
  98	gsts = readl(iommu->reg + DMAR_GSTS_REG);
  99	if (gsts & DMA_GSTS_IRES)
 100		iommu->flags |= VTD_FLAG_IRQ_REMAP_PRE_ENABLED;
 101}
 102
 103static int alloc_irte(struct intel_iommu *iommu, int irq,
 104		      struct irq_2_iommu *irq_iommu, u16 count)
 105{
 106	struct ir_table *table = iommu->ir_table;
 107	unsigned int mask = 0;
 108	unsigned long flags;
 109	int index;
 110
 111	if (!count || !irq_iommu)
 112		return -1;
 113
 114	if (count > 1) {
 115		count = __roundup_pow_of_two(count);
 116		mask = ilog2(count);
 117	}
 118
 119	if (mask > ecap_max_handle_mask(iommu->ecap)) {
 120		pr_err("Requested mask %x exceeds the max invalidation handle"
 121		       " mask value %Lx\n", mask,
 122		       ecap_max_handle_mask(iommu->ecap));
 123		return -1;
 124	}
 125
 126	raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
 127	index = bitmap_find_free_region(table->bitmap,
 128					INTR_REMAP_TABLE_ENTRIES, mask);
 129	if (index < 0) {
 130		pr_warn("IR%d: can't allocate an IRTE\n", iommu->seq_id);
 131	} else {
 132		irq_iommu->iommu = iommu;
 133		irq_iommu->irte_index =  index;
 134		irq_iommu->sub_handle = 0;
 135		irq_iommu->irte_mask = mask;
 136		irq_iommu->mode = IRQ_REMAPPING;
 137	}
 138	raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
 139
 140	return index;
 141}
 142
 143static int qi_flush_iec(struct intel_iommu *iommu, int index, int mask)
 144{
 145	struct qi_desc desc;
 146
 147	desc.low = QI_IEC_IIDEX(index) | QI_IEC_TYPE | QI_IEC_IM(mask)
 148		   | QI_IEC_SELECTIVE;
 149	desc.high = 0;
 150
 151	return qi_submit_sync(&desc, iommu);
 152}
 153
 154static int modify_irte(struct irq_2_iommu *irq_iommu,
 155		       struct irte *irte_modified)
 156{
 157	struct intel_iommu *iommu;
 158	unsigned long flags;
 159	struct irte *irte;
 160	int rc, index;
 161
 162	if (!irq_iommu)
 163		return -1;
 164
 165	raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
 166
 167	iommu = irq_iommu->iommu;
 168
 169	index = irq_iommu->irte_index + irq_iommu->sub_handle;
 170	irte = &iommu->ir_table->base[index];
 171
 172#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE)
 173	if ((irte->pst == 1) || (irte_modified->pst == 1)) {
 174		bool ret;
 175
 176		ret = cmpxchg_double(&irte->low, &irte->high,
 177				     irte->low, irte->high,
 178				     irte_modified->low, irte_modified->high);
 179		/*
 180		 * We use cmpxchg16 to atomically update the 128-bit IRTE,
 181		 * and it cannot be updated by the hardware or other processors
 182		 * behind us, so the return value of cmpxchg16 should be the
 183		 * same as the old value.
 184		 */
 185		WARN_ON(!ret);
 186	} else
 187#endif
 188	{
 189		set_64bit(&irte->low, irte_modified->low);
 190		set_64bit(&irte->high, irte_modified->high);
 191	}
 192	__iommu_flush_cache(iommu, irte, sizeof(*irte));
 193
 194	rc = qi_flush_iec(iommu, index, 0);
 195
 196	/* Update iommu mode according to the IRTE mode */
 197	irq_iommu->mode = irte->pst ? IRQ_POSTING : IRQ_REMAPPING;
 198	raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
 199
 200	return rc;
 201}
 202
 203static struct intel_iommu *map_hpet_to_ir(u8 hpet_id)
 204{
 205	int i;
 206
 207	for (i = 0; i < MAX_HPET_TBS; i++)
 208		if (ir_hpet[i].id == hpet_id && ir_hpet[i].iommu)
 209			return ir_hpet[i].iommu;
 210	return NULL;
 211}
 212
 213static struct intel_iommu *map_ioapic_to_ir(int apic)
 214{
 215	int i;
 216
 217	for (i = 0; i < MAX_IO_APICS; i++)
 218		if (ir_ioapic[i].id == apic && ir_ioapic[i].iommu)
 219			return ir_ioapic[i].iommu;
 220	return NULL;
 221}
 222
 223static struct intel_iommu *map_dev_to_ir(struct pci_dev *dev)
 224{
 225	struct dmar_drhd_unit *drhd;
 226
 227	drhd = dmar_find_matched_drhd_unit(dev);
 228	if (!drhd)
 229		return NULL;
 230
 231	return drhd->iommu;
 232}
 233
 234static int clear_entries(struct irq_2_iommu *irq_iommu)
 235{
 236	struct irte *start, *entry, *end;
 237	struct intel_iommu *iommu;
 238	int index;
 239
 240	if (irq_iommu->sub_handle)
 241		return 0;
 242
 243	iommu = irq_iommu->iommu;
 244	index = irq_iommu->irte_index;
 245
 246	start = iommu->ir_table->base + index;
 247	end = start + (1 << irq_iommu->irte_mask);
 248
 249	for (entry = start; entry < end; entry++) {
 250		set_64bit(&entry->low, 0);
 251		set_64bit(&entry->high, 0);
 252	}
 253	bitmap_release_region(iommu->ir_table->bitmap, index,
 254			      irq_iommu->irte_mask);
 255
 256	return qi_flush_iec(iommu, index, irq_iommu->irte_mask);
 257}
 258
 259/*
 260 * source validation type
 261 */
 262#define SVT_NO_VERIFY		0x0  /* no verification is required */
 263#define SVT_VERIFY_SID_SQ	0x1  /* verify using SID and SQ fields */
 264#define SVT_VERIFY_BUS		0x2  /* verify bus of request-id */
 265
 266/*
 267 * source-id qualifier
 268 */
 269#define SQ_ALL_16	0x0  /* verify all 16 bits of request-id */
 270#define SQ_13_IGNORE_1	0x1  /* verify most significant 13 bits, ignore
 271			      * the third least significant bit
 272			      */
 273#define SQ_13_IGNORE_2	0x2  /* verify most significant 13 bits, ignore
 274			      * the second and third least significant bits
 275			      */
 276#define SQ_13_IGNORE_3	0x3  /* verify most significant 13 bits, ignore
 277			      * the least three significant bits
 278			      */
 279
 280/*
 281 * set SVT, SQ and SID fields of irte to verify
 282 * source ids of interrupt requests
 283 */
 284static void set_irte_sid(struct irte *irte, unsigned int svt,
 285			 unsigned int sq, unsigned int sid)
 286{
 287	if (disable_sourceid_checking)
 288		svt = SVT_NO_VERIFY;
 289	irte->svt = svt;
 290	irte->sq = sq;
 291	irte->sid = sid;
 292}
 293
 294static int set_ioapic_sid(struct irte *irte, int apic)
 295{
 296	int i;
 297	u16 sid = 0;
 298
 299	if (!irte)
 300		return -1;
 301
 302	down_read(&dmar_global_lock);
 303	for (i = 0; i < MAX_IO_APICS; i++) {
 304		if (ir_ioapic[i].iommu && ir_ioapic[i].id == apic) {
 305			sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn;
 306			break;
 307		}
 308	}
 309	up_read(&dmar_global_lock);
 310
 311	if (sid == 0) {
 312		pr_warn("Failed to set source-id of IOAPIC (%d)\n", apic);
 313		return -1;
 314	}
 315
 316	set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, sid);
 317
 318	return 0;
 319}
 320
 321static int set_hpet_sid(struct irte *irte, u8 id)
 322{
 323	int i;
 324	u16 sid = 0;
 325
 326	if (!irte)
 327		return -1;
 328
 329	down_read(&dmar_global_lock);
 330	for (i = 0; i < MAX_HPET_TBS; i++) {
 331		if (ir_hpet[i].iommu && ir_hpet[i].id == id) {
 332			sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn;
 333			break;
 334		}
 335	}
 336	up_read(&dmar_global_lock);
 337
 338	if (sid == 0) {
 339		pr_warn("Failed to set source-id of HPET block (%d)\n", id);
 340		return -1;
 341	}
 342
 343	/*
 344	 * Should really use SQ_ALL_16. Some platforms are broken.
 345	 * While we figure out the right quirks for these broken platforms, use
 346	 * SQ_13_IGNORE_3 for now.
 347	 */
 348	set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_13_IGNORE_3, sid);
 349
 350	return 0;
 351}
 352
 353struct set_msi_sid_data {
 354	struct pci_dev *pdev;
 355	u16 alias;
 356};
 357
 358static int set_msi_sid_cb(struct pci_dev *pdev, u16 alias, void *opaque)
 359{
 360	struct set_msi_sid_data *data = opaque;
 361
 362	data->pdev = pdev;
 363	data->alias = alias;
 364
 365	return 0;
 366}
 367
 368static int set_msi_sid(struct irte *irte, struct pci_dev *dev)
 369{
 370	struct set_msi_sid_data data;
 371
 372	if (!irte || !dev)
 373		return -1;
 374
 375	pci_for_each_dma_alias(dev, set_msi_sid_cb, &data);
 376
 377	/*
 378	 * DMA alias provides us with a PCI device and alias.  The only case
 379	 * where the it will return an alias on a different bus than the
 380	 * device is the case of a PCIe-to-PCI bridge, where the alias is for
 381	 * the subordinate bus.  In this case we can only verify the bus.
 382	 *
 383	 * If the alias device is on a different bus than our source device
 384	 * then we have a topology based alias, use it.
 385	 *
 386	 * Otherwise, the alias is for a device DMA quirk and we cannot
 387	 * assume that MSI uses the same requester ID.  Therefore use the
 388	 * original device.
 389	 */
 390	if (PCI_BUS_NUM(data.alias) != data.pdev->bus->number)
 391		set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
 392			     PCI_DEVID(PCI_BUS_NUM(data.alias),
 393				       dev->bus->number));
 394	else if (data.pdev->bus->number != dev->bus->number)
 395		set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, data.alias);
 396	else
 397		set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
 398			     PCI_DEVID(dev->bus->number, dev->devfn));
 399
 400	return 0;
 401}
 402
 403static int iommu_load_old_irte(struct intel_iommu *iommu)
 404{
 405	struct irte *old_ir_table;
 406	phys_addr_t irt_phys;
 407	unsigned int i;
 408	size_t size;
 409	u64 irta;
 410
 411	if (!is_kdump_kernel()) {
 412		pr_warn("IRQ remapping was enabled on %s but we are not in kdump mode\n",
 413			iommu->name);
 414		clear_ir_pre_enabled(iommu);
 415		iommu_disable_irq_remapping(iommu);
 416		return -EINVAL;
 417	}
 418
 419	/* Check whether the old ir-table has the same size as ours */
 420	irta = dmar_readq(iommu->reg + DMAR_IRTA_REG);
 421	if ((irta & INTR_REMAP_TABLE_REG_SIZE_MASK)
 422	     != INTR_REMAP_TABLE_REG_SIZE)
 423		return -EINVAL;
 424
 425	irt_phys = irta & VTD_PAGE_MASK;
 426	size     = INTR_REMAP_TABLE_ENTRIES*sizeof(struct irte);
 427
 428	/* Map the old IR table */
 429	old_ir_table = memremap(irt_phys, size, MEMREMAP_WB);
 430	if (!old_ir_table)
 431		return -ENOMEM;
 432
 433	/* Copy data over */
 434	memcpy(iommu->ir_table->base, old_ir_table, size);
 435
 436	__iommu_flush_cache(iommu, iommu->ir_table->base, size);
 437
 438	/*
 439	 * Now check the table for used entries and mark those as
 440	 * allocated in the bitmap
 441	 */
 442	for (i = 0; i < INTR_REMAP_TABLE_ENTRIES; i++) {
 443		if (iommu->ir_table->base[i].present)
 444			bitmap_set(iommu->ir_table->bitmap, i, 1);
 445	}
 446
 447	memunmap(old_ir_table);
 448
 449	return 0;
 450}
 451
 452
 453static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
 454{
 455	unsigned long flags;
 456	u64 addr;
 457	u32 sts;
 458
 459	addr = virt_to_phys((void *)iommu->ir_table->base);
 460
 461	raw_spin_lock_irqsave(&iommu->register_lock, flags);
 462
 463	dmar_writeq(iommu->reg + DMAR_IRTA_REG,
 464		    (addr) | IR_X2APIC_MODE(mode) | INTR_REMAP_TABLE_REG_SIZE);
 465
 466	/* Set interrupt-remapping table pointer */
 467	writel(iommu->gcmd | DMA_GCMD_SIRTP, iommu->reg + DMAR_GCMD_REG);
 468
 469	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
 470		      readl, (sts & DMA_GSTS_IRTPS), sts);
 471	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 472
 473	/*
 474	 * Global invalidation of interrupt entry cache to make sure the
 475	 * hardware uses the new irq remapping table.
 476	 */
 477	qi_global_iec(iommu);
 478}
 479
 480static void iommu_enable_irq_remapping(struct intel_iommu *iommu)
 481{
 482	unsigned long flags;
 483	u32 sts;
 484
 485	raw_spin_lock_irqsave(&iommu->register_lock, flags);
 486
 487	/* Enable interrupt-remapping */
 488	iommu->gcmd |= DMA_GCMD_IRE;
 489	iommu->gcmd &= ~DMA_GCMD_CFI;  /* Block compatibility-format MSIs */
 490	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
 491
 492	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
 493		      readl, (sts & DMA_GSTS_IRES), sts);
 494
 495	/*
 496	 * With CFI clear in the Global Command register, we should be
 497	 * protected from dangerous (i.e. compatibility) interrupts
 498	 * regardless of x2apic status.  Check just to be sure.
 499	 */
 500	if (sts & DMA_GSTS_CFIS)
 501		WARN(1, KERN_WARNING
 502			"Compatibility-format IRQs enabled despite intr remapping;\n"
 503			"you are vulnerable to IRQ injection.\n");
 504
 505	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 506}
 507
 508static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 509{
 510	struct ir_table *ir_table;
 511	struct page *pages;
 512	unsigned long *bitmap;
 513
 514	if (iommu->ir_table)
 515		return 0;
 516
 517	ir_table = kzalloc(sizeof(struct ir_table), GFP_KERNEL);
 518	if (!ir_table)
 519		return -ENOMEM;
 520
 521	pages = alloc_pages_node(iommu->node, GFP_KERNEL | __GFP_ZERO,
 522				 INTR_REMAP_PAGE_ORDER);
 523	if (!pages) {
 524		pr_err("IR%d: failed to allocate pages of order %d\n",
 525		       iommu->seq_id, INTR_REMAP_PAGE_ORDER);
 526		goto out_free_table;
 527	}
 528
 529	bitmap = kcalloc(BITS_TO_LONGS(INTR_REMAP_TABLE_ENTRIES),
 530			 sizeof(long), GFP_ATOMIC);
 531	if (bitmap == NULL) {
 532		pr_err("IR%d: failed to allocate bitmap\n", iommu->seq_id);
 533		goto out_free_pages;
 534	}
 535
 536	iommu->ir_domain = irq_domain_add_hierarchy(arch_get_ir_parent_domain(),
 537						    0, INTR_REMAP_TABLE_ENTRIES,
 538						    NULL, &intel_ir_domain_ops,
 539						    iommu);
 540	if (!iommu->ir_domain) {
 541		pr_err("IR%d: failed to allocate irqdomain\n", iommu->seq_id);
 542		goto out_free_bitmap;
 543	}
 544	iommu->ir_msi_domain = arch_create_msi_irq_domain(iommu->ir_domain);
 545
 546	ir_table->base = page_address(pages);
 547	ir_table->bitmap = bitmap;
 548	iommu->ir_table = ir_table;
 549
 550	/*
 551	 * If the queued invalidation is already initialized,
 552	 * shouldn't disable it.
 553	 */
 554	if (!iommu->qi) {
 555		/*
 556		 * Clear previous faults.
 557		 */
 558		dmar_fault(-1, iommu);
 559		dmar_disable_qi(iommu);
 560
 561		if (dmar_enable_qi(iommu)) {
 562			pr_err("Failed to enable queued invalidation\n");
 563			goto out_free_bitmap;
 564		}
 565	}
 566
 567	init_ir_status(iommu);
 568
 569	if (ir_pre_enabled(iommu)) {
 570		if (iommu_load_old_irte(iommu))
 571			pr_err("Failed to copy IR table for %s from previous kernel\n",
 572			       iommu->name);
 573		else
 574			pr_info("Copied IR table for %s from previous kernel\n",
 575				iommu->name);
 576	}
 577
 578	iommu_set_irq_remapping(iommu, eim_mode);
 579
 580	return 0;
 581
 582out_free_bitmap:
 583	kfree(bitmap);
 584out_free_pages:
 585	__free_pages(pages, INTR_REMAP_PAGE_ORDER);
 586out_free_table:
 587	kfree(ir_table);
 588
 589	iommu->ir_table  = NULL;
 590
 591	return -ENOMEM;
 592}
 593
 594static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
 595{
 596	if (iommu && iommu->ir_table) {
 597		if (iommu->ir_msi_domain) {
 598			irq_domain_remove(iommu->ir_msi_domain);
 599			iommu->ir_msi_domain = NULL;
 600		}
 601		if (iommu->ir_domain) {
 602			irq_domain_remove(iommu->ir_domain);
 603			iommu->ir_domain = NULL;
 604		}
 605		free_pages((unsigned long)iommu->ir_table->base,
 606			   INTR_REMAP_PAGE_ORDER);
 607		kfree(iommu->ir_table->bitmap);
 608		kfree(iommu->ir_table);
 609		iommu->ir_table = NULL;
 610	}
 611}
 612
 613/*
 614 * Disable Interrupt Remapping.
 615 */
 616static void iommu_disable_irq_remapping(struct intel_iommu *iommu)
 617{
 618	unsigned long flags;
 619	u32 sts;
 620
 621	if (!ecap_ir_support(iommu->ecap))
 622		return;
 623
 624	/*
 625	 * global invalidation of interrupt entry cache before disabling
 626	 * interrupt-remapping.
 627	 */
 628	qi_global_iec(iommu);
 629
 630	raw_spin_lock_irqsave(&iommu->register_lock, flags);
 631
 632	sts = readl(iommu->reg + DMAR_GSTS_REG);
 633	if (!(sts & DMA_GSTS_IRES))
 634		goto end;
 635
 636	iommu->gcmd &= ~DMA_GCMD_IRE;
 637	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
 638
 639	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
 640		      readl, !(sts & DMA_GSTS_IRES), sts);
 641
 642end:
 643	raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 644}
 645
 646static int __init dmar_x2apic_optout(void)
 647{
 648	struct acpi_table_dmar *dmar;
 649	dmar = (struct acpi_table_dmar *)dmar_tbl;
 650	if (!dmar || no_x2apic_optout)
 651		return 0;
 652	return dmar->flags & DMAR_X2APIC_OPT_OUT;
 653}
 654
 655static void __init intel_cleanup_irq_remapping(void)
 656{
 657	struct dmar_drhd_unit *drhd;
 658	struct intel_iommu *iommu;
 659
 660	for_each_iommu(iommu, drhd) {
 661		if (ecap_ir_support(iommu->ecap)) {
 662			iommu_disable_irq_remapping(iommu);
 663			intel_teardown_irq_remapping(iommu);
 664		}
 665	}
 666
 667	if (x2apic_supported())
 668		pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n");
 669}
 670
 671static int __init intel_prepare_irq_remapping(void)
 672{
 673	struct dmar_drhd_unit *drhd;
 674	struct intel_iommu *iommu;
 675	int eim = 0;
 676
 677	if (irq_remap_broken) {
 678		pr_warn("This system BIOS has enabled interrupt remapping\n"
 679			"on a chipset that contains an erratum making that\n"
 680			"feature unstable.  To maintain system stability\n"
 681			"interrupt remapping is being disabled.  Please\n"
 682			"contact your BIOS vendor for an update\n");
 683		add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
 684		return -ENODEV;
 685	}
 686
 687	if (dmar_table_init() < 0)
 688		return -ENODEV;
 689
 690	if (!dmar_ir_support())
 691		return -ENODEV;
 692
 693	if (parse_ioapics_under_ir()) {
 694		pr_info("Not enabling interrupt remapping\n");
 695		goto error;
 696	}
 697
 698	/* First make sure all IOMMUs support IRQ remapping */
 699	for_each_iommu(iommu, drhd)
 700		if (!ecap_ir_support(iommu->ecap))
 701			goto error;
 702
 703	/* Detect remapping mode: lapic or x2apic */
 704	if (x2apic_supported()) {
 705		eim = !dmar_x2apic_optout();
 706		if (!eim) {
 707			pr_info("x2apic is disabled because BIOS sets x2apic opt out bit.");
 708			pr_info("Use 'intremap=no_x2apic_optout' to override the BIOS setting.\n");
 709		}
 710	}
 711
 712	for_each_iommu(iommu, drhd) {
 713		if (eim && !ecap_eim_support(iommu->ecap)) {
 714			pr_info("%s does not support EIM\n", iommu->name);
 715			eim = 0;
 716		}
 717	}
 718
 719	eim_mode = eim;
 720	if (eim)
 721		pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n");
 722
 723	/* Do the initializations early */
 724	for_each_iommu(iommu, drhd) {
 725		if (intel_setup_irq_remapping(iommu)) {
 726			pr_err("Failed to setup irq remapping for %s\n",
 727			       iommu->name);
 728			goto error;
 729		}
 730	}
 731
 732	return 0;
 733
 734error:
 735	intel_cleanup_irq_remapping();
 736	return -ENODEV;
 737}
 738
 739/*
 740 * Set Posted-Interrupts capability.
 741 */
 742static inline void set_irq_posting_cap(void)
 743{
 744	struct dmar_drhd_unit *drhd;
 745	struct intel_iommu *iommu;
 746
 747	if (!disable_irq_post) {
 748		/*
 749		 * If IRTE is in posted format, the 'pda' field goes across the
 750		 * 64-bit boundary, we need use cmpxchg16b to atomically update
 751		 * it. We only expose posted-interrupt when X86_FEATURE_CX16
 752		 * is supported. Actually, hardware platforms supporting PI
 753		 * should have X86_FEATURE_CX16 support, this has been confirmed
 754		 * with Intel hardware guys.
 755		 */
 756		if (boot_cpu_has(X86_FEATURE_CX16))
 757			intel_irq_remap_ops.capability |= 1 << IRQ_POSTING_CAP;
 758
 759		for_each_iommu(iommu, drhd)
 760			if (!cap_pi_support(iommu->cap)) {
 761				intel_irq_remap_ops.capability &=
 762						~(1 << IRQ_POSTING_CAP);
 763				break;
 764			}
 765	}
 766}
 767
 768static int __init intel_enable_irq_remapping(void)
 769{
 770	struct dmar_drhd_unit *drhd;
 771	struct intel_iommu *iommu;
 772	bool setup = false;
 773
 774	/*
 775	 * Setup Interrupt-remapping for all the DRHD's now.
 776	 */
 777	for_each_iommu(iommu, drhd) {
 778		if (!ir_pre_enabled(iommu))
 779			iommu_enable_irq_remapping(iommu);
 780		setup = true;
 781	}
 782
 783	if (!setup)
 784		goto error;
 785
 786	irq_remapping_enabled = 1;
 787
 788	set_irq_posting_cap();
 789
 790	pr_info("Enabled IRQ remapping in %s mode\n", eim_mode ? "x2apic" : "xapic");
 791
 792	return eim_mode ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
 793
 794error:
 795	intel_cleanup_irq_remapping();
 796	return -1;
 797}
 798
 799static int ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope,
 800				   struct intel_iommu *iommu,
 801				   struct acpi_dmar_hardware_unit *drhd)
 802{
 803	struct acpi_dmar_pci_path *path;
 804	u8 bus;
 805	int count, free = -1;
 806
 807	bus = scope->bus;
 808	path = (struct acpi_dmar_pci_path *)(scope + 1);
 809	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
 810		/ sizeof(struct acpi_dmar_pci_path);
 811
 812	while (--count > 0) {
 813		/*
 814		 * Access PCI directly due to the PCI
 815		 * subsystem isn't initialized yet.
 816		 */
 817		bus = read_pci_config_byte(bus, path->device, path->function,
 818					   PCI_SECONDARY_BUS);
 819		path++;
 820	}
 821
 822	for (count = 0; count < MAX_HPET_TBS; count++) {
 823		if (ir_hpet[count].iommu == iommu &&
 824		    ir_hpet[count].id == scope->enumeration_id)
 825			return 0;
 826		else if (ir_hpet[count].iommu == NULL && free == -1)
 827			free = count;
 828	}
 829	if (free == -1) {
 830		pr_warn("Exceeded Max HPET blocks\n");
 831		return -ENOSPC;
 832	}
 833
 834	ir_hpet[free].iommu = iommu;
 835	ir_hpet[free].id    = scope->enumeration_id;
 836	ir_hpet[free].bus   = bus;
 837	ir_hpet[free].devfn = PCI_DEVFN(path->device, path->function);
 838	pr_info("HPET id %d under DRHD base 0x%Lx\n",
 839		scope->enumeration_id, drhd->address);
 840
 841	return 0;
 842}
 843
 844static int ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
 845				     struct intel_iommu *iommu,
 846				     struct acpi_dmar_hardware_unit *drhd)
 847{
 848	struct acpi_dmar_pci_path *path;
 849	u8 bus;
 850	int count, free = -1;
 851
 852	bus = scope->bus;
 853	path = (struct acpi_dmar_pci_path *)(scope + 1);
 854	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
 855		/ sizeof(struct acpi_dmar_pci_path);
 856
 857	while (--count > 0) {
 858		/*
 859		 * Access PCI directly due to the PCI
 860		 * subsystem isn't initialized yet.
 861		 */
 862		bus = read_pci_config_byte(bus, path->device, path->function,
 863					   PCI_SECONDARY_BUS);
 864		path++;
 865	}
 866
 867	for (count = 0; count < MAX_IO_APICS; count++) {
 868		if (ir_ioapic[count].iommu == iommu &&
 869		    ir_ioapic[count].id == scope->enumeration_id)
 870			return 0;
 871		else if (ir_ioapic[count].iommu == NULL && free == -1)
 872			free = count;
 873	}
 874	if (free == -1) {
 875		pr_warn("Exceeded Max IO APICS\n");
 876		return -ENOSPC;
 877	}
 878
 879	ir_ioapic[free].bus   = bus;
 880	ir_ioapic[free].devfn = PCI_DEVFN(path->device, path->function);
 881	ir_ioapic[free].iommu = iommu;
 882	ir_ioapic[free].id    = scope->enumeration_id;
 883	pr_info("IOAPIC id %d under DRHD base  0x%Lx IOMMU %d\n",
 884		scope->enumeration_id, drhd->address, iommu->seq_id);
 885
 886	return 0;
 887}
 888
 889static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_header *header,
 890				      struct intel_iommu *iommu)
 891{
 892	int ret = 0;
 893	struct acpi_dmar_hardware_unit *drhd;
 894	struct acpi_dmar_device_scope *scope;
 895	void *start, *end;
 896
 897	drhd = (struct acpi_dmar_hardware_unit *)header;
 898	start = (void *)(drhd + 1);
 899	end = ((void *)drhd) + header->length;
 900
 901	while (start < end && ret == 0) {
 902		scope = start;
 903		if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC)
 904			ret = ir_parse_one_ioapic_scope(scope, iommu, drhd);
 905		else if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_HPET)
 906			ret = ir_parse_one_hpet_scope(scope, iommu, drhd);
 907		start += scope->length;
 908	}
 909
 910	return ret;
 911}
 912
 913static void ir_remove_ioapic_hpet_scope(struct intel_iommu *iommu)
 914{
 915	int i;
 916
 917	for (i = 0; i < MAX_HPET_TBS; i++)
 918		if (ir_hpet[i].iommu == iommu)
 919			ir_hpet[i].iommu = NULL;
 920
 921	for (i = 0; i < MAX_IO_APICS; i++)
 922		if (ir_ioapic[i].iommu == iommu)
 923			ir_ioapic[i].iommu = NULL;
 924}
 925
 926/*
 927 * Finds the assocaition between IOAPIC's and its Interrupt-remapping
 928 * hardware unit.
 929 */
 930static int __init parse_ioapics_under_ir(void)
 931{
 932	struct dmar_drhd_unit *drhd;
 933	struct intel_iommu *iommu;
 934	bool ir_supported = false;
 935	int ioapic_idx;
 936
 937	for_each_iommu(iommu, drhd) {
 938		int ret;
 939
 940		if (!ecap_ir_support(iommu->ecap))
 941			continue;
 942
 943		ret = ir_parse_ioapic_hpet_scope(drhd->hdr, iommu);
 944		if (ret)
 945			return ret;
 946
 947		ir_supported = true;
 948	}
 949
 950	if (!ir_supported)
 951		return -ENODEV;
 952
 953	for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) {
 954		int ioapic_id = mpc_ioapic_id(ioapic_idx);
 955		if (!map_ioapic_to_ir(ioapic_id)) {
 956			pr_err(FW_BUG "ioapic %d has no mapping iommu, "
 957			       "interrupt remapping will be disabled\n",
 958			       ioapic_id);
 959			return -1;
 960		}
 961	}
 962
 963	return 0;
 964}
 965
 966static int __init ir_dev_scope_init(void)
 967{
 968	int ret;
 969
 970	if (!irq_remapping_enabled)
 971		return 0;
 972
 973	down_write(&dmar_global_lock);
 974	ret = dmar_dev_scope_init();
 975	up_write(&dmar_global_lock);
 976
 977	return ret;
 978}
 979rootfs_initcall(ir_dev_scope_init);
 980
 981static void disable_irq_remapping(void)
 982{
 983	struct dmar_drhd_unit *drhd;
 984	struct intel_iommu *iommu = NULL;
 985
 986	/*
 987	 * Disable Interrupt-remapping for all the DRHD's now.
 988	 */
 989	for_each_iommu(iommu, drhd) {
 990		if (!ecap_ir_support(iommu->ecap))
 991			continue;
 992
 993		iommu_disable_irq_remapping(iommu);
 994	}
 995
 996	/*
 997	 * Clear Posted-Interrupts capability.
 998	 */
 999	if (!disable_irq_post)
1000		intel_irq_remap_ops.capability &= ~(1 << IRQ_POSTING_CAP);
1001}
1002
1003static int reenable_irq_remapping(int eim)
1004{
1005	struct dmar_drhd_unit *drhd;
1006	bool setup = false;
1007	struct intel_iommu *iommu = NULL;
1008
1009	for_each_iommu(iommu, drhd)
1010		if (iommu->qi)
1011			dmar_reenable_qi(iommu);
1012
1013	/*
1014	 * Setup Interrupt-remapping for all the DRHD's now.
1015	 */
1016	for_each_iommu(iommu, drhd) {
1017		if (!ecap_ir_support(iommu->ecap))
1018			continue;
1019
1020		/* Set up interrupt remapping for iommu.*/
1021		iommu_set_irq_remapping(iommu, eim);
1022		iommu_enable_irq_remapping(iommu);
1023		setup = true;
1024	}
1025
1026	if (!setup)
1027		goto error;
1028
1029	set_irq_posting_cap();
1030
1031	return 0;
1032
1033error:
1034	/*
1035	 * handle error condition gracefully here!
1036	 */
1037	return -1;
1038}
1039
1040static void prepare_irte(struct irte *irte, int vector, unsigned int dest)
1041{
1042	memset(irte, 0, sizeof(*irte));
1043
1044	irte->present = 1;
1045	irte->dst_mode = apic->irq_dest_mode;
1046	/*
1047	 * Trigger mode in the IRTE will always be edge, and for IO-APIC, the
1048	 * actual level or edge trigger will be setup in the IO-APIC
1049	 * RTE. This will help simplify level triggered irq migration.
1050	 * For more details, see the comments (in io_apic.c) explainig IO-APIC
1051	 * irq migration in the presence of interrupt-remapping.
1052	*/
1053	irte->trigger_mode = 0;
1054	irte->dlvry_mode = apic->irq_delivery_mode;
1055	irte->vector = vector;
1056	irte->dest_id = IRTE_DEST(dest);
1057	irte->redir_hint = 1;
1058}
1059
1060static struct irq_domain *intel_get_ir_irq_domain(struct irq_alloc_info *info)
1061{
1062	struct intel_iommu *iommu = NULL;
1063
1064	if (!info)
1065		return NULL;
1066
1067	switch (info->type) {
1068	case X86_IRQ_ALLOC_TYPE_IOAPIC:
1069		iommu = map_ioapic_to_ir(info->ioapic_id);
1070		break;
1071	case X86_IRQ_ALLOC_TYPE_HPET:
1072		iommu = map_hpet_to_ir(info->hpet_id);
1073		break;
1074	case X86_IRQ_ALLOC_TYPE_MSI:
1075	case X86_IRQ_ALLOC_TYPE_MSIX:
1076		iommu = map_dev_to_ir(info->msi_dev);
1077		break;
1078	default:
1079		BUG_ON(1);
1080		break;
1081	}
1082
1083	return iommu ? iommu->ir_domain : NULL;
1084}
1085
1086static struct irq_domain *intel_get_irq_domain(struct irq_alloc_info *info)
1087{
1088	struct intel_iommu *iommu;
1089
1090	if (!info)
1091		return NULL;
1092
1093	switch (info->type) {
1094	case X86_IRQ_ALLOC_TYPE_MSI:
1095	case X86_IRQ_ALLOC_TYPE_MSIX:
1096		iommu = map_dev_to_ir(info->msi_dev);
1097		if (iommu)
1098			return iommu->ir_msi_domain;
1099		break;
1100	default:
1101		break;
1102	}
1103
1104	return NULL;
1105}
1106
1107struct irq_remap_ops intel_irq_remap_ops = {
1108	.prepare		= intel_prepare_irq_remapping,
1109	.enable			= intel_enable_irq_remapping,
1110	.disable		= disable_irq_remapping,
1111	.reenable		= reenable_irq_remapping,
1112	.enable_faulting	= enable_drhd_fault_handling,
1113	.get_ir_irq_domain	= intel_get_ir_irq_domain,
1114	.get_irq_domain		= intel_get_irq_domain,
1115};
1116
1117/*
1118 * Migrate the IO-APIC irq in the presence of intr-remapping.
1119 *
1120 * For both level and edge triggered, irq migration is a simple atomic
1121 * update(of vector and cpu destination) of IRTE and flush the hardware cache.
1122 *
1123 * For level triggered, we eliminate the io-apic RTE modification (with the
1124 * updated vector information), by using a virtual vector (io-apic pin number).
1125 * Real vector that is used for interrupting cpu will be coming from
1126 * the interrupt-remapping table entry.
1127 *
1128 * As the migration is a simple atomic update of IRTE, the same mechanism
1129 * is used to migrate MSI irq's in the presence of interrupt-remapping.
1130 */
1131static int
1132intel_ir_set_affinity(struct irq_data *data, const struct cpumask *mask,
1133		      bool force)
1134{
1135	struct intel_ir_data *ir_data = data->chip_data;
1136	struct irte *irte = &ir_data->irte_entry;
1137	struct irq_cfg *cfg = irqd_cfg(data);
1138	struct irq_data *parent = data->parent_data;
1139	int ret;
1140
1141	ret = parent->chip->irq_set_affinity(parent, mask, force);
1142	if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
1143		return ret;
1144
1145	/*
1146	 * Atomically updates the IRTE with the new destination, vector
1147	 * and flushes the interrupt entry cache.
1148	 */
1149	irte->vector = cfg->vector;
1150	irte->dest_id = IRTE_DEST(cfg->dest_apicid);
1151
1152	/* Update the hardware only if the interrupt is in remapped mode. */
1153	if (ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
1154		modify_irte(&ir_data->irq_2_iommu, irte);
1155
1156	/*
1157	 * After this point, all the interrupts will start arriving
1158	 * at the new destination. So, time to cleanup the previous
1159	 * vector allocation.
1160	 */
1161	send_cleanup_vector(cfg);
1162
1163	return IRQ_SET_MASK_OK_DONE;
1164}
1165
1166static void intel_ir_compose_msi_msg(struct irq_data *irq_data,
1167				     struct msi_msg *msg)
1168{
1169	struct intel_ir_data *ir_data = irq_data->chip_data;
1170
1171	*msg = ir_data->msi_entry;
1172}
1173
1174static int intel_ir_set_vcpu_affinity(struct irq_data *data, void *info)
1175{
1176	struct intel_ir_data *ir_data = data->chip_data;
1177	struct vcpu_data *vcpu_pi_info = info;
1178
1179	/* stop posting interrupts, back to remapping mode */
1180	if (!vcpu_pi_info) {
1181		modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry);
1182	} else {
1183		struct irte irte_pi;
1184
1185		/*
1186		 * We are not caching the posted interrupt entry. We
1187		 * copy the data from the remapped entry and modify
1188		 * the fields which are relevant for posted mode. The
1189		 * cached remapped entry is used for switching back to
1190		 * remapped mode.
1191		 */
1192		memset(&irte_pi, 0, sizeof(irte_pi));
1193		dmar_copy_shared_irte(&irte_pi, &ir_data->irte_entry);
1194
1195		/* Update the posted mode fields */
1196		irte_pi.p_pst = 1;
1197		irte_pi.p_urgent = 0;
1198		irte_pi.p_vector = vcpu_pi_info->vector;
1199		irte_pi.pda_l = (vcpu_pi_info->pi_desc_addr >>
1200				(32 - PDA_LOW_BIT)) & ~(-1UL << PDA_LOW_BIT);
1201		irte_pi.pda_h = (vcpu_pi_info->pi_desc_addr >> 32) &
1202				~(-1UL << PDA_HIGH_BIT);
1203
1204		modify_irte(&ir_data->irq_2_iommu, &irte_pi);
1205	}
1206
1207	return 0;
1208}
1209
1210static struct irq_chip intel_ir_chip = {
1211	.irq_ack = ir_ack_apic_edge,
1212	.irq_set_affinity = intel_ir_set_affinity,
1213	.irq_compose_msi_msg = intel_ir_compose_msi_msg,
1214	.irq_set_vcpu_affinity = intel_ir_set_vcpu_affinity,
1215};
1216
1217static void intel_irq_remapping_prepare_irte(struct intel_ir_data *data,
1218					     struct irq_cfg *irq_cfg,
1219					     struct irq_alloc_info *info,
1220					     int index, int sub_handle)
1221{
1222	struct IR_IO_APIC_route_entry *entry;
1223	struct irte *irte = &data->irte_entry;
1224	struct msi_msg *msg = &data->msi_entry;
1225
1226	prepare_irte(irte, irq_cfg->vector, irq_cfg->dest_apicid);
1227	switch (info->type) {
1228	case X86_IRQ_ALLOC_TYPE_IOAPIC:
1229		/* Set source-id of interrupt request */
1230		set_ioapic_sid(irte, info->ioapic_id);
1231		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",
1232			info->ioapic_id, irte->present, irte->fpd,
1233			irte->dst_mode, irte->redir_hint,
1234			irte->trigger_mode, irte->dlvry_mode,
1235			irte->avail, irte->vector, irte->dest_id,
1236			irte->sid, irte->sq, irte->svt);
1237
1238		entry = (struct IR_IO_APIC_route_entry *)info->ioapic_entry;
1239		info->ioapic_entry = NULL;
1240		memset(entry, 0, sizeof(*entry));
1241		entry->index2	= (index >> 15) & 0x1;
1242		entry->zero	= 0;
1243		entry->format	= 1;
1244		entry->index	= (index & 0x7fff);
1245		/*
1246		 * IO-APIC RTE will be configured with virtual vector.
1247		 * irq handler will do the explicit EOI to the io-apic.
1248		 */
1249		entry->vector	= info->ioapic_pin;
1250		entry->mask	= 0;			/* enable IRQ */
1251		entry->trigger	= info->ioapic_trigger;
1252		entry->polarity	= info->ioapic_polarity;
1253		if (info->ioapic_trigger)
1254			entry->mask = 1; /* Mask level triggered irqs. */
1255		break;
1256
1257	case X86_IRQ_ALLOC_TYPE_HPET:
1258	case X86_IRQ_ALLOC_TYPE_MSI:
1259	case X86_IRQ_ALLOC_TYPE_MSIX:
1260		if (info->type == X86_IRQ_ALLOC_TYPE_HPET)
1261			set_hpet_sid(irte, info->hpet_id);
1262		else
1263			set_msi_sid(irte, info->msi_dev);
1264
1265		msg->address_hi = MSI_ADDR_BASE_HI;
1266		msg->data = sub_handle;
1267		msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT |
1268				  MSI_ADDR_IR_SHV |
1269				  MSI_ADDR_IR_INDEX1(index) |
1270				  MSI_ADDR_IR_INDEX2(index);
1271		break;
1272
1273	default:
1274		BUG_ON(1);
1275		break;
1276	}
1277}
1278
1279static void intel_free_irq_resources(struct irq_domain *domain,
1280				     unsigned int virq, unsigned int nr_irqs)
1281{
1282	struct irq_data *irq_data;
1283	struct intel_ir_data *data;
1284	struct irq_2_iommu *irq_iommu;
1285	unsigned long flags;
1286	int i;
1287	for (i = 0; i < nr_irqs; i++) {
1288		irq_data = irq_domain_get_irq_data(domain, virq  + i);
1289		if (irq_data && irq_data->chip_data) {
1290			data = irq_data->chip_data;
1291			irq_iommu = &data->irq_2_iommu;
1292			raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
1293			clear_entries(irq_iommu);
1294			raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
1295			irq_domain_reset_irq_data(irq_data);
1296			kfree(data);
1297		}
1298	}
1299}
1300
1301static int intel_irq_remapping_alloc(struct irq_domain *domain,
1302				     unsigned int virq, unsigned int nr_irqs,
1303				     void *arg)
1304{
1305	struct intel_iommu *iommu = domain->host_data;
1306	struct irq_alloc_info *info = arg;
1307	struct intel_ir_data *data, *ird;
1308	struct irq_data *irq_data;
1309	struct irq_cfg *irq_cfg;
1310	int i, ret, index;
1311
1312	if (!info || !iommu)
1313		return -EINVAL;
1314	if (nr_irqs > 1 && info->type != X86_IRQ_ALLOC_TYPE_MSI &&
1315	    info->type != X86_IRQ_ALLOC_TYPE_MSIX)
1316		return -EINVAL;
1317
1318	/*
1319	 * With IRQ remapping enabled, don't need contiguous CPU vectors
1320	 * to support multiple MSI interrupts.
1321	 */
1322	if (info->type == X86_IRQ_ALLOC_TYPE_MSI)
1323		info->flags &= ~X86_IRQ_ALLOC_CONTIGUOUS_VECTORS;
1324
1325	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
1326	if (ret < 0)
1327		return ret;
1328
1329	ret = -ENOMEM;
1330	data = kzalloc(sizeof(*data), GFP_KERNEL);
1331	if (!data)
1332		goto out_free_parent;
1333
1334	down_read(&dmar_global_lock);
1335	index = alloc_irte(iommu, virq, &data->irq_2_iommu, nr_irqs);
1336	up_read(&dmar_global_lock);
1337	if (index < 0) {
1338		pr_warn("Failed to allocate IRTE\n");
1339		kfree(data);
1340		goto out_free_parent;
1341	}
1342
1343	for (i = 0; i < nr_irqs; i++) {
1344		irq_data = irq_domain_get_irq_data(domain, virq + i);
1345		irq_cfg = irqd_cfg(irq_data);
1346		if (!irq_data || !irq_cfg) {
1347			ret = -EINVAL;
1348			goto out_free_data;
1349		}
1350
1351		if (i > 0) {
1352			ird = kzalloc(sizeof(*ird), GFP_KERNEL);
1353			if (!ird)
1354				goto out_free_data;
1355			/* Initialize the common data */
1356			ird->irq_2_iommu = data->irq_2_iommu;
1357			ird->irq_2_iommu.sub_handle = i;
1358		} else {
1359			ird = data;
1360		}
1361
1362		irq_data->hwirq = (index << 16) + i;
1363		irq_data->chip_data = ird;
1364		irq_data->chip = &intel_ir_chip;
1365		intel_irq_remapping_prepare_irte(ird, irq_cfg, info, index, i);
1366		irq_set_status_flags(virq + i, IRQ_MOVE_PCNTXT);
1367	}
1368	return 0;
1369
1370out_free_data:
1371	intel_free_irq_resources(domain, virq, i);
1372out_free_parent:
1373	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1374	return ret;
1375}
1376
1377static void intel_irq_remapping_free(struct irq_domain *domain,
1378				     unsigned int virq, unsigned int nr_irqs)
1379{
1380	intel_free_irq_resources(domain, virq, nr_irqs);
1381	irq_domain_free_irqs_common(domain, virq, nr_irqs);
1382}
1383
1384static void intel_irq_remapping_activate(struct irq_domain *domain,
1385					 struct irq_data *irq_data)
1386{
1387	struct intel_ir_data *data = irq_data->chip_data;
1388
1389	modify_irte(&data->irq_2_iommu, &data->irte_entry);
1390}
1391
1392static void intel_irq_remapping_deactivate(struct irq_domain *domain,
1393					   struct irq_data *irq_data)
1394{
1395	struct intel_ir_data *data = irq_data->chip_data;
1396	struct irte entry;
1397
1398	memset(&entry, 0, sizeof(entry));
1399	modify_irte(&data->irq_2_iommu, &entry);
1400}
1401
1402static struct irq_domain_ops intel_ir_domain_ops = {
1403	.alloc = intel_irq_remapping_alloc,
1404	.free = intel_irq_remapping_free,
1405	.activate = intel_irq_remapping_activate,
1406	.deactivate = intel_irq_remapping_deactivate,
1407};
1408
1409/*
1410 * Support of Interrupt Remapping Unit Hotplug
1411 */
1412static int dmar_ir_add(struct dmar_drhd_unit *dmaru, struct intel_iommu *iommu)
1413{
1414	int ret;
1415	int eim = x2apic_enabled();
1416
1417	if (eim && !ecap_eim_support(iommu->ecap)) {
1418		pr_info("DRHD %Lx: EIM not supported by DRHD, ecap %Lx\n",
1419			iommu->reg_phys, iommu->ecap);
1420		return -ENODEV;
1421	}
1422
1423	if (ir_parse_ioapic_hpet_scope(dmaru->hdr, iommu)) {
1424		pr_warn("DRHD %Lx: failed to parse managed IOAPIC/HPET\n",
1425			iommu->reg_phys);
1426		return -ENODEV;
1427	}
1428
1429	/* TODO: check all IOAPICs are covered by IOMMU */
1430
1431	/* Setup Interrupt-remapping now. */
1432	ret = intel_setup_irq_remapping(iommu);
1433	if (ret) {
1434		pr_err("Failed to setup irq remapping for %s\n",
1435		       iommu->name);
1436		intel_teardown_irq_remapping(iommu);
1437		ir_remove_ioapic_hpet_scope(iommu);
1438	} else {
1439		iommu_enable_irq_remapping(iommu);
1440	}
1441
1442	return ret;
1443}
1444
1445int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert)
1446{
1447	int ret = 0;
1448	struct intel_iommu *iommu = dmaru->iommu;
1449
1450	if (!irq_remapping_enabled)
1451		return 0;
1452	if (iommu == NULL)
1453		return -EINVAL;
1454	if (!ecap_ir_support(iommu->ecap))
1455		return 0;
1456	if (irq_remapping_cap(IRQ_POSTING_CAP) &&
1457	    !cap_pi_support(iommu->cap))
1458		return -EBUSY;
1459
1460	if (insert) {
1461		if (!iommu->ir_table)
1462			ret = dmar_ir_add(dmaru, iommu);
1463	} else {
1464		if (iommu->ir_table) {
1465			if (!bitmap_empty(iommu->ir_table->bitmap,
1466					  INTR_REMAP_TABLE_ENTRIES)) {
1467				ret = -EBUSY;
1468			} else {
1469				iommu_disable_irq_remapping(iommu);
1470				intel_teardown_irq_remapping(iommu);
1471				ir_remove_ioapic_hpet_scope(iommu);
1472			}
1473		}
1474	}
1475
1476	return ret;
1477}