diff options
Diffstat (limited to 'drivers/iommu/intel_irq_remapping.c')
| -rw-r--r-- | drivers/iommu/intel_irq_remapping.c | 1514 |
1 files changed, 1514 insertions, 0 deletions
diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c new file mode 100644 index 000000000..17fc262f2 --- /dev/null +++ b/drivers/iommu/intel_irq_remapping.c @@ -0,0 +1,1514 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define pr_fmt(fmt) "DMAR-IR: " fmt + +#include <linux/interrupt.h> +#include <linux/dmar.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/hpet.h> +#include <linux/pci.h> +#include <linux/irq.h> +#include <linux/intel-iommu.h> +#include <linux/acpi.h> +#include <linux/irqdomain.h> +#include <linux/crash_dump.h> +#include <asm/io_apic.h> +#include <asm/smp.h> +#include <asm/cpu.h> +#include <asm/irq_remapping.h> +#include <asm/pci-direct.h> +#include <asm/msidef.h> + +#include "irq_remapping.h" + +enum irq_mode { + IRQ_REMAPPING, + IRQ_POSTING, +}; + +struct ioapic_scope { + struct intel_iommu *iommu; + unsigned int id; + unsigned int bus; /* PCI bus number */ + unsigned int devfn; /* PCI devfn number */ +}; + +struct hpet_scope { + struct intel_iommu *iommu; + u8 id; + unsigned int bus; + unsigned int devfn; +}; + +struct irq_2_iommu { + struct intel_iommu *iommu; + u16 irte_index; + u16 sub_handle; + u8 irte_mask; + enum irq_mode mode; +}; + +struct intel_ir_data { + struct irq_2_iommu irq_2_iommu; + struct irte irte_entry; + union { + struct msi_msg msi_entry; + }; +}; + +#define IR_X2APIC_MODE(mode) (mode ? (1 << 11) : 0) +#define IRTE_DEST(dest) ((eim_mode) ? dest : dest << 8) + +static int __read_mostly eim_mode; +static struct ioapic_scope ir_ioapic[MAX_IO_APICS]; +static struct hpet_scope ir_hpet[MAX_HPET_TBS]; + +/* + * Lock ordering: + * ->dmar_global_lock + * ->irq_2_ir_lock + * ->qi->q_lock + * ->iommu->register_lock + * Note: + * intel_irq_remap_ops.{supported,prepare,enable,disable,reenable} are called + * in single-threaded environment with interrupt disabled, so no need to tabke + * the dmar_global_lock. + */ +static DEFINE_RAW_SPINLOCK(irq_2_ir_lock); +static const struct irq_domain_ops intel_ir_domain_ops; + +static void iommu_disable_irq_remapping(struct intel_iommu *iommu); +static int __init parse_ioapics_under_ir(void); + +static bool ir_pre_enabled(struct intel_iommu *iommu) +{ + return (iommu->flags & VTD_FLAG_IRQ_REMAP_PRE_ENABLED); +} + +static void clear_ir_pre_enabled(struct intel_iommu *iommu) +{ + iommu->flags &= ~VTD_FLAG_IRQ_REMAP_PRE_ENABLED; +} + +static void init_ir_status(struct intel_iommu *iommu) +{ + u32 gsts; + + gsts = readl(iommu->reg + DMAR_GSTS_REG); + if (gsts & DMA_GSTS_IRES) + iommu->flags |= VTD_FLAG_IRQ_REMAP_PRE_ENABLED; +} + +static int alloc_irte(struct intel_iommu *iommu, int irq, + struct irq_2_iommu *irq_iommu, u16 count) +{ + struct ir_table *table = iommu->ir_table; + unsigned int mask = 0; + unsigned long flags; + int index; + + if (!count || !irq_iommu) + return -1; + + if (count > 1) { + count = __roundup_pow_of_two(count); + mask = ilog2(count); + } + + if (mask > ecap_max_handle_mask(iommu->ecap)) { + pr_err("Requested mask %x exceeds the max invalidation handle" + " mask value %Lx\n", mask, + ecap_max_handle_mask(iommu->ecap)); + return -1; + } + + raw_spin_lock_irqsave(&irq_2_ir_lock, flags); + index = bitmap_find_free_region(table->bitmap, + INTR_REMAP_TABLE_ENTRIES, mask); + if (index < 0) { + pr_warn("IR%d: can't allocate an IRTE\n", iommu->seq_id); + } else { + irq_iommu->iommu = iommu; + irq_iommu->irte_index = index; + irq_iommu->sub_handle = 0; + irq_iommu->irte_mask = mask; + irq_iommu->mode = IRQ_REMAPPING; + } + raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags); + + return index; +} + +static int qi_flush_iec(struct intel_iommu *iommu, int index, int mask) +{ + struct qi_desc desc; + + desc.low = QI_IEC_IIDEX(index) | QI_IEC_TYPE | QI_IEC_IM(mask) + | QI_IEC_SELECTIVE; + desc.high = 0; + + return qi_submit_sync(&desc, iommu); +} + +static int modify_irte(struct irq_2_iommu *irq_iommu, + struct irte *irte_modified) +{ + struct intel_iommu *iommu; + unsigned long flags; + struct irte *irte; + int rc, index; + + if (!irq_iommu) + return -1; + + raw_spin_lock_irqsave(&irq_2_ir_lock, flags); + + iommu = irq_iommu->iommu; + + index = irq_iommu->irte_index + irq_iommu->sub_handle; + irte = &iommu->ir_table->base[index]; + +#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) + if ((irte->pst == 1) || (irte_modified->pst == 1)) { + bool ret; + + ret = cmpxchg_double(&irte->low, &irte->high, + irte->low, irte->high, + irte_modified->low, irte_modified->high); + /* + * We use cmpxchg16 to atomically update the 128-bit IRTE, + * and it cannot be updated by the hardware or other processors + * behind us, so the return value of cmpxchg16 should be the + * same as the old value. + */ + WARN_ON(!ret); + } else +#endif + { + set_64bit(&irte->low, irte_modified->low); + set_64bit(&irte->high, irte_modified->high); + } + __iommu_flush_cache(iommu, irte, sizeof(*irte)); + + rc = qi_flush_iec(iommu, index, 0); + + /* Update iommu mode according to the IRTE mode */ + irq_iommu->mode = irte->pst ? IRQ_POSTING : IRQ_REMAPPING; + raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags); + + return rc; +} + +static struct intel_iommu *map_hpet_to_ir(u8 hpet_id) +{ + int i; + + for (i = 0; i < MAX_HPET_TBS; i++) + if (ir_hpet[i].id == hpet_id && ir_hpet[i].iommu) + return ir_hpet[i].iommu; + return NULL; +} + +static struct intel_iommu *map_ioapic_to_ir(int apic) +{ + int i; + + for (i = 0; i < MAX_IO_APICS; i++) + if (ir_ioapic[i].id == apic && ir_ioapic[i].iommu) + return ir_ioapic[i].iommu; + return NULL; +} + +static struct intel_iommu *map_dev_to_ir(struct pci_dev *dev) +{ + struct dmar_drhd_unit *drhd; + + drhd = dmar_find_matched_drhd_unit(dev); + if (!drhd) + return NULL; + + return drhd->iommu; +} + +static int clear_entries(struct irq_2_iommu *irq_iommu) +{ + struct irte *start, *entry, *end; + struct intel_iommu *iommu; + int index; + + if (irq_iommu->sub_handle) + return 0; + + iommu = irq_iommu->iommu; + index = irq_iommu->irte_index; + + start = iommu->ir_table->base + index; + end = start + (1 << irq_iommu->irte_mask); + + for (entry = start; entry < end; entry++) { + set_64bit(&entry->low, 0); + set_64bit(&entry->high, 0); + } + bitmap_release_region(iommu->ir_table->bitmap, index, + irq_iommu->irte_mask); + + return qi_flush_iec(iommu, index, irq_iommu->irte_mask); +} + +/* + * source validation type + */ +#define SVT_NO_VERIFY 0x0 /* no verification is required */ +#define SVT_VERIFY_SID_SQ 0x1 /* verify using SID and SQ fields */ +#define SVT_VERIFY_BUS 0x2 /* verify bus of request-id */ + +/* + * source-id qualifier + */ +#define SQ_ALL_16 0x0 /* verify all 16 bits of request-id */ +#define SQ_13_IGNORE_1 0x1 /* verify most significant 13 bits, ignore + * the third least significant bit + */ +#define SQ_13_IGNORE_2 0x2 /* verify most significant 13 bits, ignore + * the second and third least significant bits + */ +#define SQ_13_IGNORE_3 0x3 /* verify most significant 13 bits, ignore + * the least three significant bits + */ + +/* + * set SVT, SQ and SID fields of irte to verify + * source ids of interrupt requests + */ +static void set_irte_sid(struct irte *irte, unsigned int svt, + unsigned int sq, unsigned int sid) +{ + if (disable_sourceid_checking) + svt = SVT_NO_VERIFY; + irte->svt = svt; + irte->sq = sq; + irte->sid = sid; +} + +static int set_ioapic_sid(struct irte *irte, int apic) +{ + int i; + u16 sid = 0; + + if (!irte) + return -1; + + down_read(&dmar_global_lock); + for (i = 0; i < MAX_IO_APICS; i++) { + if (ir_ioapic[i].iommu && ir_ioapic[i].id == apic) { + sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn; + break; + } + } + up_read(&dmar_global_lock); + + if (sid == 0) { + pr_warn("Failed to set source-id of IOAPIC (%d)\n", apic); + return -1; + } + + set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, sid); + + return 0; +} + +static int set_hpet_sid(struct irte *irte, u8 id) +{ + int i; + u16 sid = 0; + + if (!irte) + return -1; + + down_read(&dmar_global_lock); + for (i = 0; i < MAX_HPET_TBS; i++) { + if (ir_hpet[i].iommu && ir_hpet[i].id == id) { + sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn; + break; + } + } + up_read(&dmar_global_lock); + + if (sid == 0) { + pr_warn("Failed to set source-id of HPET block (%d)\n", id); + return -1; + } + + /* + * Should really use SQ_ALL_16. Some platforms are broken. + * While we figure out the right quirks for these broken platforms, use + * SQ_13_IGNORE_3 for now. + */ + set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_13_IGNORE_3, sid); + + return 0; +} + +struct set_msi_sid_data { + struct pci_dev *pdev; + u16 alias; +}; + +static int set_msi_sid_cb(struct pci_dev *pdev, u16 alias, void *opaque) +{ + struct set_msi_sid_data *data = opaque; + + data->pdev = pdev; + data->alias = alias; + + return 0; +} + +static int set_msi_sid(struct irte *irte, struct pci_dev *dev) +{ + struct set_msi_sid_data data; + + if (!irte || !dev) + return -1; + + pci_for_each_dma_alias(dev, set_msi_sid_cb, &data); + + /* + * DMA alias provides us with a PCI device and alias. The only case + * where the it will return an alias on a different bus than the + * device is the case of a PCIe-to-PCI bridge, where the alias is for + * the subordinate bus. In this case we can only verify the bus. + * + * If the alias device is on a different bus than our source device + * then we have a topology based alias, use it. + * + * Otherwise, the alias is for a device DMA quirk and we cannot + * assume that MSI uses the same requester ID. Therefore use the + * original device. + */ + if (PCI_BUS_NUM(data.alias) != data.pdev->bus->number) + set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16, + PCI_DEVID(PCI_BUS_NUM(data.alias), + dev->bus->number)); + else if (data.pdev->bus->number != dev->bus->number) + set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, data.alias); + else + set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, + PCI_DEVID(dev->bus->number, dev->devfn)); + + return 0; +} + +static int iommu_load_old_irte(struct intel_iommu *iommu) +{ + struct irte *old_ir_table; + phys_addr_t irt_phys; + unsigned int i; + size_t size; + u64 irta; + + /* Check whether the old ir-table has the same size as ours */ + irta = dmar_readq(iommu->reg + DMAR_IRTA_REG); + if ((irta & INTR_REMAP_TABLE_REG_SIZE_MASK) + != INTR_REMAP_TABLE_REG_SIZE) + return -EINVAL; + + irt_phys = irta & VTD_PAGE_MASK; + size = INTR_REMAP_TABLE_ENTRIES*sizeof(struct irte); + + /* Map the old IR table */ + old_ir_table = memremap(irt_phys, size, MEMREMAP_WB); + if (!old_ir_table) + return -ENOMEM; + + /* Copy data over */ + memcpy(iommu->ir_table->base, old_ir_table, size); + + __iommu_flush_cache(iommu, iommu->ir_table->base, size); + + /* + * Now check the table for used entries and mark those as + * allocated in the bitmap + */ + for (i = 0; i < INTR_REMAP_TABLE_ENTRIES; i++) { + if (iommu->ir_table->base[i].present) + bitmap_set(iommu->ir_table->bitmap, i, 1); + } + + memunmap(old_ir_table); + + return 0; +} + + +static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode) +{ + unsigned long flags; + u64 addr; + u32 sts; + + addr = virt_to_phys((void *)iommu->ir_table->base); + + raw_spin_lock_irqsave(&iommu->register_lock, flags); + + dmar_writeq(iommu->reg + DMAR_IRTA_REG, + (addr) | IR_X2APIC_MODE(mode) | INTR_REMAP_TABLE_REG_SIZE); + + /* Set interrupt-remapping table pointer */ + writel(iommu->gcmd | DMA_GCMD_SIRTP, iommu->reg + DMAR_GCMD_REG); + + IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, + readl, (sts & DMA_GSTS_IRTPS), sts); + raw_spin_unlock_irqrestore(&iommu->register_lock, flags); + + /* + * Global invalidation of interrupt entry cache to make sure the + * hardware uses the new irq remapping table. + */ + qi_global_iec(iommu); +} + +static void iommu_enable_irq_remapping(struct intel_iommu *iommu) +{ + unsigned long flags; + u32 sts; + + raw_spin_lock_irqsave(&iommu->register_lock, flags); + + /* Enable interrupt-remapping */ + iommu->gcmd |= DMA_GCMD_IRE; + writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG); + IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, + readl, (sts & DMA_GSTS_IRES), sts); + + /* Block compatibility-format MSIs */ + if (sts & DMA_GSTS_CFIS) { + iommu->gcmd &= ~DMA_GCMD_CFI; + writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG); + IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, + readl, !(sts & DMA_GSTS_CFIS), sts); + } + + /* + * With CFI clear in the Global Command register, we should be + * protected from dangerous (i.e. compatibility) interrupts + * regardless of x2apic status. Check just to be sure. + */ + if (sts & DMA_GSTS_CFIS) + WARN(1, KERN_WARNING + "Compatibility-format IRQs enabled despite intr remapping;\n" + "you are vulnerable to IRQ injection.\n"); + + raw_spin_unlock_irqrestore(&iommu->register_lock, flags); +} + +static int intel_setup_irq_remapping(struct intel_iommu *iommu) +{ + struct ir_table *ir_table; + struct fwnode_handle *fn; + unsigned long *bitmap; + struct page *pages; + + if (iommu->ir_table) + return 0; + + ir_table = kzalloc(sizeof(struct ir_table), GFP_KERNEL); + if (!ir_table) + return -ENOMEM; + + pages = alloc_pages_node(iommu->node, GFP_KERNEL | __GFP_ZERO, + INTR_REMAP_PAGE_ORDER); + if (!pages) { + pr_err("IR%d: failed to allocate pages of order %d\n", + iommu->seq_id, INTR_REMAP_PAGE_ORDER); + goto out_free_table; + } + + bitmap = kcalloc(BITS_TO_LONGS(INTR_REMAP_TABLE_ENTRIES), + sizeof(long), GFP_ATOMIC); + if (bitmap == NULL) { + pr_err("IR%d: failed to allocate bitmap\n", iommu->seq_id); + goto out_free_pages; + } + + fn = irq_domain_alloc_named_id_fwnode("INTEL-IR", iommu->seq_id); + if (!fn) + goto out_free_bitmap; + + iommu->ir_domain = + irq_domain_create_hierarchy(arch_get_ir_parent_domain(), + 0, INTR_REMAP_TABLE_ENTRIES, + fn, &intel_ir_domain_ops, + iommu); + if (!iommu->ir_domain) { + pr_err("IR%d: failed to allocate irqdomain\n", iommu->seq_id); + goto out_free_fwnode; + } + iommu->ir_msi_domain = + arch_create_remap_msi_irq_domain(iommu->ir_domain, + "INTEL-IR-MSI", + iommu->seq_id); + + ir_table->base = page_address(pages); + ir_table->bitmap = bitmap; + iommu->ir_table = ir_table; + + /* + * If the queued invalidation is already initialized, + * shouldn't disable it. + */ + if (!iommu->qi) { + /* + * Clear previous faults. + */ + dmar_fault(-1, iommu); + dmar_disable_qi(iommu); + + if (dmar_enable_qi(iommu)) { + pr_err("Failed to enable queued invalidation\n"); + goto out_free_ir_domain; + } + } + + init_ir_status(iommu); + + if (ir_pre_enabled(iommu)) { + if (!is_kdump_kernel()) { + pr_warn("IRQ remapping was enabled on %s but we are not in kdump mode\n", + iommu->name); + clear_ir_pre_enabled(iommu); + iommu_disable_irq_remapping(iommu); + } else if (iommu_load_old_irte(iommu)) + pr_err("Failed to copy IR table for %s from previous kernel\n", + iommu->name); + else + pr_info("Copied IR table for %s from previous kernel\n", + iommu->name); + } + + iommu_set_irq_remapping(iommu, eim_mode); + + return 0; + +out_free_ir_domain: + if (iommu->ir_msi_domain) + irq_domain_remove(iommu->ir_msi_domain); + iommu->ir_msi_domain = NULL; + irq_domain_remove(iommu->ir_domain); + iommu->ir_domain = NULL; +out_free_fwnode: + irq_domain_free_fwnode(fn); +out_free_bitmap: + kfree(bitmap); +out_free_pages: + __free_pages(pages, INTR_REMAP_PAGE_ORDER); +out_free_table: + kfree(ir_table); + + iommu->ir_table = NULL; + + return -ENOMEM; +} + +static void intel_teardown_irq_remapping(struct intel_iommu *iommu) +{ + struct fwnode_handle *fn; + + if (iommu && iommu->ir_table) { + if (iommu->ir_msi_domain) { + fn = iommu->ir_msi_domain->fwnode; + + irq_domain_remove(iommu->ir_msi_domain); + irq_domain_free_fwnode(fn); + iommu->ir_msi_domain = NULL; + } + if (iommu->ir_domain) { + fn = iommu->ir_domain->fwnode; + + irq_domain_remove(iommu->ir_domain); + irq_domain_free_fwnode(fn); + iommu->ir_domain = NULL; + } + free_pages((unsigned long)iommu->ir_table->base, + INTR_REMAP_PAGE_ORDER); + kfree(iommu->ir_table->bitmap); + kfree(iommu->ir_table); + iommu->ir_table = NULL; + } +} + +/* + * Disable Interrupt Remapping. + */ +static void iommu_disable_irq_remapping(struct intel_iommu *iommu) +{ + unsigned long flags; + u32 sts; + + if (!ecap_ir_support(iommu->ecap)) + return; + + /* + * global invalidation of interrupt entry cache before disabling + * interrupt-remapping. + */ + qi_global_iec(iommu); + + raw_spin_lock_irqsave(&iommu->register_lock, flags); + + sts = readl(iommu->reg + DMAR_GSTS_REG); + if (!(sts & DMA_GSTS_IRES)) + goto end; + + iommu->gcmd &= ~DMA_GCMD_IRE; + writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG); + + IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, + readl, !(sts & DMA_GSTS_IRES), sts); + +end: + raw_spin_unlock_irqrestore(&iommu->register_lock, flags); +} + +static int __init dmar_x2apic_optout(void) +{ + struct acpi_table_dmar *dmar; + dmar = (struct acpi_table_dmar *)dmar_tbl; + if (!dmar || no_x2apic_optout) + return 0; + return dmar->flags & DMAR_X2APIC_OPT_OUT; +} + +static void __init intel_cleanup_irq_remapping(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu; + + for_each_iommu(iommu, drhd) { + if (ecap_ir_support(iommu->ecap)) { + iommu_disable_irq_remapping(iommu); + intel_teardown_irq_remapping(iommu); + } + } + + if (x2apic_supported()) + pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n"); +} + +static int __init intel_prepare_irq_remapping(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu; + int eim = 0; + + if (irq_remap_broken) { + pr_warn("This system BIOS has enabled interrupt remapping\n" + "on a chipset that contains an erratum making that\n" + "feature unstable. To maintain system stability\n" + "interrupt remapping is being disabled. Please\n" + "contact your BIOS vendor for an update\n"); + add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); + return -ENODEV; + } + + if (dmar_table_init() < 0) + return -ENODEV; + + if (!dmar_ir_support()) + return -ENODEV; + + if (parse_ioapics_under_ir()) { + pr_info("Not enabling interrupt remapping\n"); + goto error; + } + + /* First make sure all IOMMUs support IRQ remapping */ + for_each_iommu(iommu, drhd) + if (!ecap_ir_support(iommu->ecap)) + goto error; + + /* Detect remapping mode: lapic or x2apic */ + if (x2apic_supported()) { + eim = !dmar_x2apic_optout(); + if (!eim) { + pr_info("x2apic is disabled because BIOS sets x2apic opt out bit."); + pr_info("Use 'intremap=no_x2apic_optout' to override the BIOS setting.\n"); + } + } + + for_each_iommu(iommu, drhd) { + if (eim && !ecap_eim_support(iommu->ecap)) { + pr_info("%s does not support EIM\n", iommu->name); + eim = 0; + } + } + + eim_mode = eim; + if (eim) + pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n"); + + /* Do the initializations early */ + for_each_iommu(iommu, drhd) { + if (intel_setup_irq_remapping(iommu)) { + pr_err("Failed to setup irq remapping for %s\n", + iommu->name); + goto error; + } + } + + return 0; + +error: + intel_cleanup_irq_remapping(); + return -ENODEV; +} + +/* + * Set Posted-Interrupts capability. + */ +static inline void set_irq_posting_cap(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu; + + if (!disable_irq_post) { + /* + * If IRTE is in posted format, the 'pda' field goes across the + * 64-bit boundary, we need use cmpxchg16b to atomically update + * it. We only expose posted-interrupt when X86_FEATURE_CX16 + * is supported. Actually, hardware platforms supporting PI + * should have X86_FEATURE_CX16 support, this has been confirmed + * with Intel hardware guys. + */ + if (boot_cpu_has(X86_FEATURE_CX16)) + intel_irq_remap_ops.capability |= 1 << IRQ_POSTING_CAP; + + for_each_iommu(iommu, drhd) + if (!cap_pi_support(iommu->cap)) { + intel_irq_remap_ops.capability &= + ~(1 << IRQ_POSTING_CAP); + break; + } + } +} + +static int __init intel_enable_irq_remapping(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu; + bool setup = false; + + /* + * Setup Interrupt-remapping for all the DRHD's now. + */ + for_each_iommu(iommu, drhd) { + if (!ir_pre_enabled(iommu)) + iommu_enable_irq_remapping(iommu); + setup = true; + } + + if (!setup) + goto error; + + irq_remapping_enabled = 1; + + set_irq_posting_cap(); + + pr_info("Enabled IRQ remapping in %s mode\n", eim_mode ? "x2apic" : "xapic"); + + return eim_mode ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE; + +error: + intel_cleanup_irq_remapping(); + return -1; +} + +static int ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope, + struct intel_iommu *iommu, + struct acpi_dmar_hardware_unit *drhd) +{ + struct acpi_dmar_pci_path *path; + u8 bus; + int count, free = -1; + + bus = scope->bus; + path = (struct acpi_dmar_pci_path *)(scope + 1); + count = (scope->length - sizeof(struct acpi_dmar_device_scope)) + / sizeof(struct acpi_dmar_pci_path); + + while (--count > 0) { + /* + * Access PCI directly due to the PCI + * subsystem isn't initialized yet. + */ + bus = read_pci_config_byte(bus, path->device, path->function, + PCI_SECONDARY_BUS); + path++; + } + + for (count = 0; count < MAX_HPET_TBS; count++) { + if (ir_hpet[count].iommu == iommu && + ir_hpet[count].id == scope->enumeration_id) + return 0; + else if (ir_hpet[count].iommu == NULL && free == -1) + free = count; + } + if (free == -1) { + pr_warn("Exceeded Max HPET blocks\n"); + return -ENOSPC; + } + + ir_hpet[free].iommu = iommu; + ir_hpet[free].id = scope->enumeration_id; + ir_hpet[free].bus = bus; + ir_hpet[free].devfn = PCI_DEVFN(path->device, path->function); + pr_info("HPET id %d under DRHD base 0x%Lx\n", + scope->enumeration_id, drhd->address); + + return 0; +} + +static int ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope, + struct intel_iommu *iommu, + struct acpi_dmar_hardware_unit *drhd) +{ + struct acpi_dmar_pci_path *path; + u8 bus; + int count, free = -1; + + bus = scope->bus; + path = (struct acpi_dmar_pci_path *)(scope + 1); + count = (scope->length - sizeof(struct acpi_dmar_device_scope)) + / sizeof(struct acpi_dmar_pci_path); + + while (--count > 0) { + /* + * Access PCI directly due to the PCI + * subsystem isn't initialized yet. + */ + bus = read_pci_config_byte(bus, path->device, path->function, + PCI_SECONDARY_BUS); + path++; + } + + for (count = 0; count < MAX_IO_APICS; count++) { + if (ir_ioapic[count].iommu == iommu && + ir_ioapic[count].id == scope->enumeration_id) + return 0; + else if (ir_ioapic[count].iommu == NULL && free == -1) + free = count; + } + if (free == -1) { + pr_warn("Exceeded Max IO APICS\n"); + return -ENOSPC; + } + + ir_ioapic[free].bus = bus; + ir_ioapic[free].devfn = PCI_DEVFN(path->device, path->function); + ir_ioapic[free].iommu = iommu; + ir_ioapic[free].id = scope->enumeration_id; + pr_info("IOAPIC id %d under DRHD base 0x%Lx IOMMU %d\n", + scope->enumeration_id, drhd->address, iommu->seq_id); + + return 0; +} + +static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_header *header, + struct intel_iommu *iommu) +{ + int ret = 0; + struct acpi_dmar_hardware_unit *drhd; + struct acpi_dmar_device_scope *scope; + void *start, *end; + + drhd = (struct acpi_dmar_hardware_unit *)header; + start = (void *)(drhd + 1); + end = ((void *)drhd) + header->length; + + while (start < end && ret == 0) { + scope = start; + if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC) + ret = ir_parse_one_ioapic_scope(scope, iommu, drhd); + else if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_HPET) + ret = ir_parse_one_hpet_scope(scope, iommu, drhd); + start += scope->length; + } + + return ret; +} + +static void ir_remove_ioapic_hpet_scope(struct intel_iommu *iommu) +{ + int i; + + for (i = 0; i < MAX_HPET_TBS; i++) + if (ir_hpet[i].iommu == iommu) + ir_hpet[i].iommu = NULL; + + for (i = 0; i < MAX_IO_APICS; i++) + if (ir_ioapic[i].iommu == iommu) + ir_ioapic[i].iommu = NULL; +} + +/* + * Finds the assocaition between IOAPIC's and its Interrupt-remapping + * hardware unit. + */ +static int __init parse_ioapics_under_ir(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu; + bool ir_supported = false; + int ioapic_idx; + + for_each_iommu(iommu, drhd) { + int ret; + + if (!ecap_ir_support(iommu->ecap)) + continue; + + ret = ir_parse_ioapic_hpet_scope(drhd->hdr, iommu); + if (ret) + return ret; + + ir_supported = true; + } + + if (!ir_supported) + return -ENODEV; + + for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) { + int ioapic_id = mpc_ioapic_id(ioapic_idx); + if (!map_ioapic_to_ir(ioapic_id)) { + pr_err(FW_BUG "ioapic %d has no mapping iommu, " + "interrupt remapping will be disabled\n", + ioapic_id); + return -1; + } + } + + return 0; +} + +static int __init ir_dev_scope_init(void) +{ + int ret; + + if (!irq_remapping_enabled) + return 0; + + down_write(&dmar_global_lock); + ret = dmar_dev_scope_init(); + up_write(&dmar_global_lock); + + return ret; +} +rootfs_initcall(ir_dev_scope_init); + +static void disable_irq_remapping(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu = NULL; + + /* + * Disable Interrupt-remapping for all the DRHD's now. + */ + for_each_iommu(iommu, drhd) { + if (!ecap_ir_support(iommu->ecap)) + continue; + + iommu_disable_irq_remapping(iommu); + } + + /* + * Clear Posted-Interrupts capability. + */ + if (!disable_irq_post) + intel_irq_remap_ops.capability &= ~(1 << IRQ_POSTING_CAP); +} + +static int reenable_irq_remapping(int eim) +{ + struct dmar_drhd_unit *drhd; + bool setup = false; + struct intel_iommu *iommu = NULL; + + for_each_iommu(iommu, drhd) + if (iommu->qi) + dmar_reenable_qi(iommu); + + /* + * Setup Interrupt-remapping for all the DRHD's now. + */ + for_each_iommu(iommu, drhd) { + if (!ecap_ir_support(iommu->ecap)) + continue; + + /* Set up interrupt remapping for iommu.*/ + iommu_set_irq_remapping(iommu, eim); + iommu_enable_irq_remapping(iommu); + setup = true; + } + + if (!setup) + goto error; + + set_irq_posting_cap(); + + return 0; + +error: + /* + * handle error condition gracefully here! + */ + return -1; +} + +static void prepare_irte(struct irte *irte, int vector, unsigned int dest) +{ + memset(irte, 0, sizeof(*irte)); + + irte->present = 1; + irte->dst_mode = apic->irq_dest_mode; + /* + * Trigger mode in the IRTE will always be edge, and for IO-APIC, the + * actual level or edge trigger will be setup in the IO-APIC + * RTE. This will help simplify level triggered irq migration. + * For more details, see the comments (in io_apic.c) explainig IO-APIC + * irq migration in the presence of interrupt-remapping. + */ + irte->trigger_mode = 0; + irte->dlvry_mode = apic->irq_delivery_mode; + irte->vector = vector; + irte->dest_id = IRTE_DEST(dest); + irte->redir_hint = 1; +} + +static struct irq_domain *intel_get_ir_irq_domain(struct irq_alloc_info *info) +{ + struct intel_iommu *iommu = NULL; + + if (!info) + return NULL; + + switch (info->type) { + case X86_IRQ_ALLOC_TYPE_IOAPIC: + iommu = map_ioapic_to_ir(info->ioapic_id); + break; + case X86_IRQ_ALLOC_TYPE_HPET: + iommu = map_hpet_to_ir(info->hpet_id); + break; + case X86_IRQ_ALLOC_TYPE_MSI: + case X86_IRQ_ALLOC_TYPE_MSIX: + iommu = map_dev_to_ir(info->msi_dev); + break; + default: + BUG_ON(1); + break; + } + + return iommu ? iommu->ir_domain : NULL; +} + +static struct irq_domain *intel_get_irq_domain(struct irq_alloc_info *info) +{ + struct intel_iommu *iommu; + + if (!info) + return NULL; + + switch (info->type) { + case X86_IRQ_ALLOC_TYPE_MSI: + case X86_IRQ_ALLOC_TYPE_MSIX: + iommu = map_dev_to_ir(info->msi_dev); + if (iommu) + return iommu->ir_msi_domain; + break; + default: + break; + } + + return NULL; +} + +struct irq_remap_ops intel_irq_remap_ops = { + .prepare = intel_prepare_irq_remapping, + .enable = intel_enable_irq_remapping, + .disable = disable_irq_remapping, + .reenable = reenable_irq_remapping, + .enable_faulting = enable_drhd_fault_handling, + .get_ir_irq_domain = intel_get_ir_irq_domain, + .get_irq_domain = intel_get_irq_domain, +}; + +static void intel_ir_reconfigure_irte(struct irq_data *irqd, bool force) +{ + struct intel_ir_data *ir_data = irqd->chip_data; + struct irte *irte = &ir_data->irte_entry; + struct irq_cfg *cfg = irqd_cfg(irqd); + + /* + * Atomically updates the IRTE with the new destination, vector + * and flushes the interrupt entry cache. + */ + irte->vector = cfg->vector; + irte->dest_id = IRTE_DEST(cfg->dest_apicid); + + /* Update the hardware only if the interrupt is in remapped mode. */ + if (force || ir_data->irq_2_iommu.mode == IRQ_REMAPPING) + modify_irte(&ir_data->irq_2_iommu, irte); +} + +/* + * Migrate the IO-APIC irq in the presence of intr-remapping. + * + * For both level and edge triggered, irq migration is a simple atomic + * update(of vector and cpu destination) of IRTE and flush the hardware cache. + * + * For level triggered, we eliminate the io-apic RTE modification (with the + * updated vector information), by using a virtual vector (io-apic pin number). + * Real vector that is used for interrupting cpu will be coming from + * the interrupt-remapping table entry. + * + * As the migration is a simple atomic update of IRTE, the same mechanism + * is used to migrate MSI irq's in the presence of interrupt-remapping. + */ +static int +intel_ir_set_affinity(struct irq_data *data, const struct cpumask *mask, + bool force) +{ + struct irq_data *parent = data->parent_data; + struct irq_cfg *cfg = irqd_cfg(data); + int ret; + + ret = parent->chip->irq_set_affinity(parent, mask, force); + if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE) + return ret; + + intel_ir_reconfigure_irte(data, false); + /* + * After this point, all the interrupts will start arriving + * at the new destination. So, time to cleanup the previous + * vector allocation. + */ + send_cleanup_vector(cfg); + + return IRQ_SET_MASK_OK_DONE; +} + +static void intel_ir_compose_msi_msg(struct irq_data *irq_data, + struct msi_msg *msg) +{ + struct intel_ir_data *ir_data = irq_data->chip_data; + + *msg = ir_data->msi_entry; +} + +static int intel_ir_set_vcpu_affinity(struct irq_data *data, void *info) +{ + struct intel_ir_data *ir_data = data->chip_data; + struct vcpu_data *vcpu_pi_info = info; + + /* stop posting interrupts, back to remapping mode */ + if (!vcpu_pi_info) { + modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry); + } else { + struct irte irte_pi; + + /* + * We are not caching the posted interrupt entry. We + * copy the data from the remapped entry and modify + * the fields which are relevant for posted mode. The + * cached remapped entry is used for switching back to + * remapped mode. + */ + memset(&irte_pi, 0, sizeof(irte_pi)); + dmar_copy_shared_irte(&irte_pi, &ir_data->irte_entry); + + /* Update the posted mode fields */ + irte_pi.p_pst = 1; + irte_pi.p_urgent = 0; + irte_pi.p_vector = vcpu_pi_info->vector; + irte_pi.pda_l = (vcpu_pi_info->pi_desc_addr >> + (32 - PDA_LOW_BIT)) & ~(-1UL << PDA_LOW_BIT); + irte_pi.pda_h = (vcpu_pi_info->pi_desc_addr >> 32) & + ~(-1UL << PDA_HIGH_BIT); + + modify_irte(&ir_data->irq_2_iommu, &irte_pi); + } + + return 0; +} + +static struct irq_chip intel_ir_chip = { + .name = "INTEL-IR", + .irq_ack = apic_ack_irq, + .irq_set_affinity = intel_ir_set_affinity, + .irq_compose_msi_msg = intel_ir_compose_msi_msg, + .irq_set_vcpu_affinity = intel_ir_set_vcpu_affinity, +}; + +static void 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) +{ + struct IR_IO_APIC_route_entry *entry; + struct irte *irte = &data->irte_entry; + struct msi_msg *msg = &data->msi_entry; + + prepare_irte(irte, irq_cfg->vector, irq_cfg->dest_apicid); + switch (info->type) { + case X86_IRQ_ALLOC_TYPE_IOAPIC: + /* Set source-id of interrupt request */ + set_ioapic_sid(irte, info->ioapic_id); + 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", + info->ioapic_id, irte->present, irte->fpd, + irte->dst_mode, irte->redir_hint, + irte->trigger_mode, irte->dlvry_mode, + irte->avail, irte->vector, irte->dest_id, + irte->sid, irte->sq, irte->svt); + + entry = (struct IR_IO_APIC_route_entry *)info->ioapic_entry; + info->ioapic_entry = NULL; + memset(entry, 0, sizeof(*entry)); + entry->index2 = (index >> 15) & 0x1; + entry->zero = 0; + entry->format = 1; + entry->index = (index & 0x7fff); + /* + * IO-APIC RTE will be configured with virtual vector. + * irq handler will do the explicit EOI to the io-apic. + */ + entry->vector = info->ioapic_pin; + entry->mask = 0; /* enable IRQ */ + entry->trigger = info->ioapic_trigger; + entry->polarity = info->ioapic_polarity; + if (info->ioapic_trigger) + entry->mask = 1; /* Mask level triggered irqs. */ + break; + + case X86_IRQ_ALLOC_TYPE_HPET: + case X86_IRQ_ALLOC_TYPE_MSI: + case X86_IRQ_ALLOC_TYPE_MSIX: + if (info->type == X86_IRQ_ALLOC_TYPE_HPET) + set_hpet_sid(irte, info->hpet_id); + else + set_msi_sid(irte, info->msi_dev); + + msg->address_hi = MSI_ADDR_BASE_HI; + msg->data = sub_handle; + msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT | + MSI_ADDR_IR_SHV | + MSI_ADDR_IR_INDEX1(index) | + MSI_ADDR_IR_INDEX2(index); + break; + + default: + BUG_ON(1); + break; + } +} + +static void intel_free_irq_resources(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs) +{ + struct irq_data *irq_data; + struct intel_ir_data *data; + struct irq_2_iommu *irq_iommu; + unsigned long flags; + int i; + for (i = 0; i < nr_irqs; i++) { + irq_data = irq_domain_get_irq_data(domain, virq + i); + if (irq_data && irq_data->chip_data) { + data = irq_data->chip_data; + irq_iommu = &data->irq_2_iommu; + raw_spin_lock_irqsave(&irq_2_ir_lock, flags); + clear_entries(irq_iommu); + raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags); + irq_domain_reset_irq_data(irq_data); + kfree(data); + } + } +} + +static int intel_irq_remapping_alloc(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs, + void *arg) +{ + struct intel_iommu *iommu = domain->host_data; + struct irq_alloc_info *info = arg; + struct intel_ir_data *data, *ird; + struct irq_data *irq_data; + struct irq_cfg *irq_cfg; + int i, ret, index; + + if (!info || !iommu) + return -EINVAL; + if (nr_irqs > 1 && info->type != X86_IRQ_ALLOC_TYPE_MSI && + info->type != X86_IRQ_ALLOC_TYPE_MSIX) + return -EINVAL; + + /* + * With IRQ remapping enabled, don't need contiguous CPU vectors + * to support multiple MSI interrupts. + */ + if (info->type == X86_IRQ_ALLOC_TYPE_MSI) + info->flags &= ~X86_IRQ_ALLOC_CONTIGUOUS_VECTORS; + + ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg); + if (ret < 0) + return ret; + + ret = -ENOMEM; + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + goto out_free_parent; + + down_read(&dmar_global_lock); + index = alloc_irte(iommu, virq, &data->irq_2_iommu, nr_irqs); + up_read(&dmar_global_lock); + if (index < 0) { + pr_warn("Failed to allocate IRTE\n"); + kfree(data); + goto out_free_parent; + } + + for (i = 0; i < nr_irqs; i++) { + irq_data = irq_domain_get_irq_data(domain, virq + i); + irq_cfg = irqd_cfg(irq_data); + if (!irq_data || !irq_cfg) { + if (!i) + kfree(data); + ret = -EINVAL; + goto out_free_data; + } + + if (i > 0) { + ird = kzalloc(sizeof(*ird), GFP_KERNEL); + if (!ird) + goto out_free_data; + /* Initialize the common data */ + ird->irq_2_iommu = data->irq_2_iommu; + ird->irq_2_iommu.sub_handle = i; + } else { + ird = data; + } + + irq_data->hwirq = (index << 16) + i; + irq_data->chip_data = ird; + irq_data->chip = &intel_ir_chip; + intel_irq_remapping_prepare_irte(ird, irq_cfg, info, index, i); + irq_set_status_flags(virq + i, IRQ_MOVE_PCNTXT); + } + return 0; + +out_free_data: + intel_free_irq_resources(domain, virq, i); +out_free_parent: + irq_domain_free_irqs_common(domain, virq, nr_irqs); + return ret; +} + +static void intel_irq_remapping_free(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs) +{ + intel_free_irq_resources(domain, virq, nr_irqs); + irq_domain_free_irqs_common(domain, virq, nr_irqs); +} + +static int intel_irq_remapping_activate(struct irq_domain *domain, + struct irq_data *irq_data, bool reserve) +{ + intel_ir_reconfigure_irte(irq_data, true); + return 0; +} + +static void intel_irq_remapping_deactivate(struct irq_domain *domain, + struct irq_data *irq_data) +{ + struct intel_ir_data *data = irq_data->chip_data; + struct irte entry; + + memset(&entry, 0, sizeof(entry)); + modify_irte(&data->irq_2_iommu, &entry); +} + +static const struct irq_domain_ops intel_ir_domain_ops = { + .alloc = intel_irq_remapping_alloc, + .free = intel_irq_remapping_free, + .activate = intel_irq_remapping_activate, + .deactivate = intel_irq_remapping_deactivate, +}; + +/* + * Support of Interrupt Remapping Unit Hotplug + */ +static int dmar_ir_add(struct dmar_drhd_unit *dmaru, struct intel_iommu *iommu) +{ + int ret; + int eim = x2apic_enabled(); + + if (eim && !ecap_eim_support(iommu->ecap)) { + pr_info("DRHD %Lx: EIM not supported by DRHD, ecap %Lx\n", + iommu->reg_phys, iommu->ecap); + return -ENODEV; + } + + if (ir_parse_ioapic_hpet_scope(dmaru->hdr, iommu)) { + pr_warn("DRHD %Lx: failed to parse managed IOAPIC/HPET\n", + iommu->reg_phys); + return -ENODEV; + } + + /* TODO: check all IOAPICs are covered by IOMMU */ + + /* Setup Interrupt-remapping now. */ + ret = intel_setup_irq_remapping(iommu); + if (ret) { + pr_err("Failed to setup irq remapping for %s\n", + iommu->name); + intel_teardown_irq_remapping(iommu); + ir_remove_ioapic_hpet_scope(iommu); + } else { + iommu_enable_irq_remapping(iommu); + } + + return ret; +} + +int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert) +{ + int ret = 0; + struct intel_iommu *iommu = dmaru->iommu; + + if (!irq_remapping_enabled) + return 0; + if (iommu == NULL) + return -EINVAL; + if (!ecap_ir_support(iommu->ecap)) + return 0; + if (irq_remapping_cap(IRQ_POSTING_CAP) && + !cap_pi_support(iommu->cap)) + return -EBUSY; + + if (insert) { + if (!iommu->ir_table) + ret = dmar_ir_add(dmaru, iommu); + } else { + if (iommu->ir_table) { + if (!bitmap_empty(iommu->ir_table->bitmap, + INTR_REMAP_TABLE_ENTRIES)) { + ret = -EBUSY; + } else { + iommu_disable_irq_remapping(iommu); + intel_teardown_irq_remapping(iommu); + ir_remove_ioapic_hpet_scope(iommu); + } + } + } + + return ret; +} |