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path: root/drivers/iommu/intel_irq_remapping.c
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Diffstat (limited to 'drivers/iommu/intel_irq_remapping.c')
-rw-r--r--drivers/iommu/intel_irq_remapping.c1301
1 files changed, 1301 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..5709ae9c3
--- /dev/null
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -0,0 +1,1301 @@
+#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 <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"
+
+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;
+};
+
+#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 int __init parse_ioapics_under_ir(void);
+
+static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
+{
+ struct irq_cfg *cfg = irq_cfg(irq);
+ return cfg ? &cfg->irq_2_iommu : NULL;
+}
+
+static int get_irte(int irq, struct irte *entry)
+{
+ struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+ unsigned long flags;
+ int index;
+
+ if (!entry || !irq_iommu)
+ return -1;
+
+ raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
+
+ if (unlikely(!irq_iommu->iommu)) {
+ raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+ return -1;
+ }
+
+ index = irq_iommu->irte_index + irq_iommu->sub_handle;
+ *entry = *(irq_iommu->iommu->ir_table->base + index);
+
+ raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+ return 0;
+}
+
+static int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
+{
+ struct ir_table *table = iommu->ir_table;
+ struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+ struct irq_cfg *cfg = irq_cfg(irq);
+ 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)) {
+ printk(KERN_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 {
+ cfg->remapped = 1;
+ irq_iommu->iommu = iommu;
+ irq_iommu->irte_index = index;
+ irq_iommu->sub_handle = 0;
+ irq_iommu->irte_mask = mask;
+ }
+ 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 map_irq_to_irte_handle(int irq, u16 *sub_handle)
+{
+ struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+ unsigned long flags;
+ int index;
+
+ if (!irq_iommu)
+ return -1;
+
+ raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
+ *sub_handle = irq_iommu->sub_handle;
+ index = irq_iommu->irte_index;
+ raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+ return index;
+}
+
+static int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
+{
+ struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+ struct irq_cfg *cfg = irq_cfg(irq);
+ unsigned long flags;
+
+ if (!irq_iommu)
+ return -1;
+
+ raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
+
+ cfg->remapped = 1;
+ irq_iommu->iommu = iommu;
+ irq_iommu->irte_index = index;
+ irq_iommu->sub_handle = subhandle;
+ irq_iommu->irte_mask = 0;
+
+ raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+
+ return 0;
+}
+
+static int modify_irte(int irq, struct irte *irte_modified)
+{
+ struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+ 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];
+
+ 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);
+ 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 + irq_iommu->sub_handle;
+
+ 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);
+}
+
+static int free_irte(int irq)
+{
+ struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+ unsigned long flags;
+ int rc;
+
+ if (!irq_iommu)
+ return -1;
+
+ raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
+
+ rc = clear_entries(irq_iommu);
+
+ irq_iommu->iommu = NULL;
+ irq_iommu->irte_index = 0;
+ irq_iommu->sub_handle = 0;
+ irq_iommu->irte_mask = 0;
+
+ raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+
+ return rc;
+}
+
+/*
+ * 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_warning("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_warning("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 void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
+{
+ u64 addr;
+ u32 sts;
+ unsigned long flags;
+
+ 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 before enabling
+ * interrupt-remapping.
+ */
+ qi_global_iec(iommu);
+
+ raw_spin_lock_irqsave(&iommu->register_lock, flags);
+
+ /* Enable interrupt-remapping */
+ iommu->gcmd |= DMA_GCMD_IRE;
+ iommu->gcmd &= ~DMA_GCMD_CFI; /* Block compatibility-format MSIs */
+ writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+ IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+ readl, (sts & DMA_GSTS_IRES), 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 page *pages;
+ unsigned long *bitmap;
+
+ 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;
+ }
+
+ ir_table->base = page_address(pages);
+ ir_table->bitmap = bitmap;
+ iommu->ir_table = ir_table;
+ return 0;
+
+out_free_pages:
+ __free_pages(pages, INTR_REMAP_PAGE_ORDER);
+out_free_table:
+ kfree(ir_table);
+ return -ENOMEM;
+}
+
+static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
+{
+ if (iommu && iommu->ir_table) {
+ 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 = dmar_readq(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;
+
+ if (irq_remap_broken) {
+ printk(KERN_WARNING
+ "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() != 1) {
+ printk(KERN_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;
+
+ /* Do the allocations early */
+ for_each_iommu(iommu, drhd)
+ if (intel_setup_irq_remapping(iommu))
+ goto error;
+
+ return 0;
+
+error:
+ intel_cleanup_irq_remapping();
+ return -ENODEV;
+}
+
+static int __init intel_enable_irq_remapping(void)
+{
+ struct dmar_drhd_unit *drhd;
+ struct intel_iommu *iommu;
+ bool setup = false;
+ int eim = 0;
+
+ if (x2apic_supported()) {
+ eim = !dmar_x2apic_optout();
+ if (!eim)
+ pr_info("x2apic is disabled because BIOS sets x2apic opt out bit. You can use 'intremap=no_x2apic_optout' to override the BIOS setting.\n");
+ }
+
+ for_each_iommu(iommu, drhd) {
+ /*
+ * If the queued invalidation is already initialized,
+ * shouldn't disable it.
+ */
+ if (iommu->qi)
+ continue;
+
+ /*
+ * Clear previous faults.
+ */
+ dmar_fault(-1, iommu);
+
+ /*
+ * Disable intr remapping and queued invalidation, if already
+ * enabled prior to OS handover.
+ */
+ iommu_disable_irq_remapping(iommu);
+
+ dmar_disable_qi(iommu);
+ }
+
+ /*
+ * check for the Interrupt-remapping support
+ */
+ for_each_iommu(iommu, drhd)
+ if (eim && !ecap_eim_support(iommu->ecap)) {
+ printk(KERN_INFO "DRHD %Lx: EIM not supported by DRHD, "
+ " ecap %Lx\n", drhd->reg_base_addr, iommu->ecap);
+ eim = 0;
+ }
+ eim_mode = eim;
+ if (eim)
+ pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n");
+
+ /*
+ * Enable queued invalidation for all the DRHD's.
+ */
+ for_each_iommu(iommu, drhd) {
+ int ret = dmar_enable_qi(iommu);
+
+ if (ret) {
+ printk(KERN_ERR "DRHD %Lx: failed to enable queued, "
+ " invalidation, ecap %Lx, ret %d\n",
+ drhd->reg_base_addr, iommu->ecap, ret);
+ goto error;
+ }
+ }
+
+ /*
+ * Setup Interrupt-remapping for all the DRHD's now.
+ */
+ for_each_iommu(iommu, drhd) {
+ iommu_set_irq_remapping(iommu, eim);
+ setup = true;
+ }
+
+ if (!setup)
+ goto error;
+
+ irq_remapping_enabled = 1;
+
+ /*
+ * VT-d has a different layout for IO-APIC entries when
+ * interrupt remapping is enabled. So it needs a special routine
+ * to print IO-APIC entries for debugging purposes too.
+ */
+ x86_io_apic_ops.print_entries = intel_ir_io_apic_print_entries;
+
+ pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
+
+ return eim ? 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)
+ if (ecap_ir_support(iommu->ecap)) {
+ if (ir_parse_ioapic_hpet_scope(drhd->hdr, iommu))
+ return -1;
+
+ ir_supported = true;
+ }
+
+ if (!ir_supported)
+ return 0;
+
+ 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 1;
+}
+
+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);
+ }
+}
+
+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);
+ setup = true;
+ }
+
+ if (!setup)
+ goto error;
+
+ 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 int intel_setup_ioapic_entry(int irq,
+ struct IO_APIC_route_entry *route_entry,
+ unsigned int destination, int vector,
+ struct io_apic_irq_attr *attr)
+{
+ int ioapic_id = mpc_ioapic_id(attr->ioapic);
+ struct intel_iommu *iommu;
+ struct IR_IO_APIC_route_entry *entry;
+ struct irte irte;
+ int index;
+
+ down_read(&dmar_global_lock);
+ iommu = map_ioapic_to_ir(ioapic_id);
+ if (!iommu) {
+ pr_warn("No mapping iommu for ioapic %d\n", ioapic_id);
+ index = -ENODEV;
+ } else {
+ index = alloc_irte(iommu, irq, 1);
+ if (index < 0) {
+ pr_warn("Failed to allocate IRTE for ioapic %d\n",
+ ioapic_id);
+ index = -ENOMEM;
+ }
+ }
+ up_read(&dmar_global_lock);
+ if (index < 0)
+ return index;
+
+ prepare_irte(&irte, vector, destination);
+
+ /* Set source-id of interrupt request */
+ set_ioapic_sid(&irte, ioapic_id);
+
+ modify_irte(irq, &irte);
+
+ 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",
+ attr->ioapic, 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 *)route_entry;
+ 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 = attr->ioapic_pin;
+ entry->mask = 0; /* enable IRQ */
+ entry->trigger = attr->trigger;
+ entry->polarity = attr->polarity;
+
+ /* Mask level triggered irqs.
+ * Use IRQ_DELAYED_DISABLE for edge triggered irqs.
+ */
+ if (attr->trigger)
+ entry->mask = 1;
+
+ return 0;
+}
+
+/*
+ * 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_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
+ bool force)
+{
+ struct irq_cfg *cfg = irqd_cfg(data);
+ unsigned int dest, irq = data->irq;
+ struct irte irte;
+ int err;
+
+ if (!config_enabled(CONFIG_SMP))
+ return -EINVAL;
+
+ if (!cpumask_intersects(mask, cpu_online_mask))
+ return -EINVAL;
+
+ if (get_irte(irq, &irte))
+ return -EBUSY;
+
+ err = assign_irq_vector(irq, cfg, mask);
+ if (err)
+ return err;
+
+ err = apic->cpu_mask_to_apicid_and(cfg->domain, mask, &dest);
+ if (err) {
+ if (assign_irq_vector(irq, cfg, data->affinity))
+ pr_err("Failed to recover vector for irq %d\n", irq);
+ return err;
+ }
+
+ irte.vector = cfg->vector;
+ irte.dest_id = IRTE_DEST(dest);
+
+ /*
+ * Atomically updates the IRTE with the new destination, vector
+ * and flushes the interrupt entry cache.
+ */
+ modify_irte(irq, &irte);
+
+ /*
+ * After this point, all the interrupts will start arriving
+ * at the new destination. So, time to cleanup the previous
+ * vector allocation.
+ */
+ if (cfg->move_in_progress)
+ send_cleanup_vector(cfg);
+
+ cpumask_copy(data->affinity, mask);
+ return 0;
+}
+
+static void intel_compose_msi_msg(struct pci_dev *pdev,
+ unsigned int irq, unsigned int dest,
+ struct msi_msg *msg, u8 hpet_id)
+{
+ struct irq_cfg *cfg;
+ struct irte irte;
+ u16 sub_handle = 0;
+ int ir_index;
+
+ cfg = irq_cfg(irq);
+
+ ir_index = map_irq_to_irte_handle(irq, &sub_handle);
+ BUG_ON(ir_index == -1);
+
+ prepare_irte(&irte, cfg->vector, dest);
+
+ /* Set source-id of interrupt request */
+ if (pdev)
+ set_msi_sid(&irte, pdev);
+ else
+ set_hpet_sid(&irte, hpet_id);
+
+ modify_irte(irq, &irte);
+
+ 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(ir_index) |
+ MSI_ADDR_IR_INDEX2(ir_index);
+}
+
+/*
+ * Map the PCI dev to the corresponding remapping hardware unit
+ * and allocate 'nvec' consecutive interrupt-remapping table entries
+ * in it.
+ */
+static int intel_msi_alloc_irq(struct pci_dev *dev, int irq, int nvec)
+{
+ struct intel_iommu *iommu;
+ int index;
+
+ down_read(&dmar_global_lock);
+ iommu = map_dev_to_ir(dev);
+ if (!iommu) {
+ printk(KERN_ERR
+ "Unable to map PCI %s to iommu\n", pci_name(dev));
+ index = -ENOENT;
+ } else {
+ index = alloc_irte(iommu, irq, nvec);
+ if (index < 0) {
+ printk(KERN_ERR
+ "Unable to allocate %d IRTE for PCI %s\n",
+ nvec, pci_name(dev));
+ index = -ENOSPC;
+ }
+ }
+ up_read(&dmar_global_lock);
+
+ return index;
+}
+
+static int intel_msi_setup_irq(struct pci_dev *pdev, unsigned int irq,
+ int index, int sub_handle)
+{
+ struct intel_iommu *iommu;
+ int ret = -ENOENT;
+
+ down_read(&dmar_global_lock);
+ iommu = map_dev_to_ir(pdev);
+ if (iommu) {
+ /*
+ * setup the mapping between the irq and the IRTE
+ * base index, the sub_handle pointing to the
+ * appropriate interrupt remap table entry.
+ */
+ set_irte_irq(irq, iommu, index, sub_handle);
+ ret = 0;
+ }
+ up_read(&dmar_global_lock);
+
+ return ret;
+}
+
+static int intel_alloc_hpet_msi(unsigned int irq, unsigned int id)
+{
+ int ret = -1;
+ struct intel_iommu *iommu;
+ int index;
+
+ down_read(&dmar_global_lock);
+ iommu = map_hpet_to_ir(id);
+ if (iommu) {
+ index = alloc_irte(iommu, irq, 1);
+ if (index >= 0)
+ ret = 0;
+ }
+ up_read(&dmar_global_lock);
+
+ return ret;
+}
+
+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,
+ .setup_ioapic_entry = intel_setup_ioapic_entry,
+ .set_affinity = intel_ioapic_set_affinity,
+ .free_irq = free_irte,
+ .compose_msi_msg = intel_compose_msi_msg,
+ .msi_alloc_irq = intel_msi_alloc_irq,
+ .msi_setup_irq = intel_msi_setup_irq,
+ .alloc_hpet_msi = intel_alloc_hpet_msi,
+};
+
+/*
+ * 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("DRHD %Lx: failed to allocate resource\n",
+ iommu->reg_phys);
+ ir_remove_ioapic_hpet_scope(iommu);
+ return ret;
+ }
+
+ if (!iommu->qi) {
+ /* Clear previous faults. */
+ dmar_fault(-1, iommu);
+ iommu_disable_irq_remapping(iommu);
+ dmar_disable_qi(iommu);
+ }
+
+ /* Enable queued invalidation */
+ ret = dmar_enable_qi(iommu);
+ if (!ret) {
+ iommu_set_irq_remapping(iommu, eim);
+ } else {
+ pr_err("DRHD %Lx: failed to enable queued invalidation, ecap %Lx, ret %d\n",
+ iommu->reg_phys, iommu->ecap, ret);
+ intel_teardown_irq_remapping(iommu);
+ ir_remove_ioapic_hpet_scope(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 (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;
+}