[Patch Part1 v8 10/37] irq_remapping/vt-d: Enhance Intel IR driver to support hierarchy irqdomain

From: Jiang Liu
Date: Mon Apr 13 2015 - 02:11:42 EST


Enhance Intel interrupt remapping driver to support hierarchy irqdomain,
it will simplify the code eventually. It also implements intel_ir_chip
to support stacked irq_chip.

Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
Acked-by: Joerg Roedel <jroedel@xxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Rafael J. Wysocki <rjw@xxxxxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Yinghai Lu <yinghai@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1416894816-23245-11-git-send-email-jiang.liu@xxxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
drivers/iommu/intel_irq_remapping.c | 337 ++++++++++++++++++++++++++++++++++-
include/linux/intel-iommu.h | 4 +
2 files changed, 333 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index d3adaf32b3ec..f2dbb0d54d17 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -8,6 +8,7 @@
#include <linux/irq.h>
#include <linux/intel-iommu.h>
#include <linux/acpi.h>
+#include <linux/irqdomain.h>
#include <asm/io_apic.h>
#include <asm/smp.h>
#include <asm/cpu.h>
@@ -31,6 +32,14 @@ struct hpet_scope {
unsigned int devfn;
};

+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)

@@ -50,6 +59,7 @@ static struct hpet_scope ir_hpet[MAX_HPET_TBS];
* the dmar_global_lock.
*/
static DEFINE_RAW_SPINLOCK(irq_2_ir_lock);
+static struct irq_domain_ops intel_ir_domain_ops;

static int __init parse_ioapics_under_ir(void);

@@ -263,7 +273,7 @@ static int free_irte(int irq)
unsigned long flags;
int rc;

- if (!irq_iommu)
+ if (!irq_iommu || irq_iommu->iommu == NULL)
return -1;

raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
@@ -488,7 +498,6 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)

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);
@@ -502,11 +511,23 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu)
goto out_free_pages;
}

+ iommu->ir_domain = irq_domain_add_hierarchy(arch_get_ir_parent_domain(),
+ 0, INTR_REMAP_TABLE_ENTRIES,
+ NULL, &intel_ir_domain_ops,
+ iommu);
+ if (!iommu->ir_domain) {
+ pr_err("IR%d: failed to allocate irqdomain\n", iommu->seq_id);
+ goto out_free_bitmap;
+ }
+ iommu->ir_msi_domain = arch_create_msi_irq_domain(iommu->ir_domain);
+
ir_table->base = page_address(pages);
ir_table->bitmap = bitmap;
iommu->ir_table = ir_table;
return 0;

+out_free_bitmap:
+ kfree(bitmap);
out_free_pages:
__free_pages(pages, INTR_REMAP_PAGE_ORDER);
out_free_table:
@@ -517,6 +538,14 @@ out_free_table:
static void intel_teardown_irq_remapping(struct intel_iommu *iommu)
{
if (iommu && iommu->ir_table) {
+ if (iommu->ir_msi_domain) {
+ irq_domain_remove(iommu->ir_msi_domain);
+ iommu->ir_msi_domain = NULL;
+ }
+ if (iommu->ir_domain) {
+ irq_domain_remove(iommu->ir_domain);
+ iommu->ir_domain = NULL;
+ }
free_pages((unsigned long)iommu->ir_table->base,
INTR_REMAP_PAGE_ORDER);
kfree(iommu->ir_table->bitmap);
@@ -1062,12 +1091,6 @@ intel_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
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;

@@ -1100,6 +1123,7 @@ intel_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
send_cleanup_vector(cfg);

cpumask_copy(data->affinity, mask);
+
return 0;
}

@@ -1205,6 +1229,53 @@ static int intel_alloc_hpet_msi(unsigned int irq, unsigned int id)
return ret;
}

+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,
@@ -1218,6 +1289,256 @@ struct irq_remap_ops intel_irq_remap_ops = {
.msi_alloc_irq = intel_msi_alloc_irq,
.msi_setup_irq = intel_msi_setup_irq,
.alloc_hpet_msi = intel_alloc_hpet_msi,
+ .get_ir_irq_domain = intel_get_ir_irq_domain,
+ .get_irq_domain = intel_get_irq_domain,
+};
+
+/*
+ * 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 intel_ir_data *ir_data = data->chip_data;
+ struct irte *irte = &ir_data->irte_entry;
+ struct irq_cfg *cfg = irqd_cfg(data);
+ struct irq_data *parent = data->parent_data;
+ int ret;
+
+ ret = parent->chip->irq_set_affinity(parent, mask, force);
+ if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
+ return ret;
+
+ /*
+ * 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);
+ modify_irte(&ir_data->irq_2_iommu, 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);
+
+ 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 struct irq_chip intel_ir_chip = {
+ .irq_ack = ir_ack_apic_edge,
+ .irq_set_affinity = intel_ir_set_affinity,
+ .irq_compose_msi_msg = intel_ir_compose_msi_msg,
+};
+
+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;
+ 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 contigious CPU vectors
+ * to support multiple MSI interrupts.
+ */
+ if (info->type == X86_IRQ_ALLOC_TYPE_MSI)
+ info->flags &= ~X86_IRQ_ALLOC_CONTIGOUS_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) {
+ ret = -EINVAL;
+ goto out_free_data;
+ }
+
+ if (i > 0) {
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ goto out_free_data;
+ }
+ irq_data->hwirq = (index << 16) + i;
+ irq_data->chip_data = data;
+ irq_data->chip = &intel_ir_chip;
+ intel_irq_remapping_prepare_irte(data, 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 void intel_irq_remapping_activate(struct irq_domain *domain,
+ struct irq_data *irq_data)
+{
+ struct intel_ir_data *data = irq_data->chip_data;
+
+ modify_irte(&data->irq_2_iommu, &data->irte_entry);
+}
+
+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 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,
};

/*
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index a65208a8fe18..ecaf3a937845 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -286,6 +286,8 @@ struct q_inval {

#define INTR_REMAP_TABLE_ENTRIES 65536

+struct irq_domain;
+
struct ir_table {
struct irte *base;
unsigned long *bitmap;
@@ -335,6 +337,8 @@ struct intel_iommu {

#ifdef CONFIG_IRQ_REMAP
struct ir_table *ir_table; /* Interrupt remapping info */
+ struct irq_domain *ir_domain;
+ struct irq_domain *ir_msi_domain;
#endif
struct device *iommu_dev; /* IOMMU-sysfs device */
int node;
--
1.7.10.4

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