Re: [Patch Part3 V6 5/8] iommu/vt-d: Enhance intel_irq_remapping driver to support DMAR unit hotplug

From: Yijing Wang
Date: Fri Sep 19 2014 - 02:50:17 EST

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In reply to: Jiang Liu: "[Patch Part3 V6 5/8] iommu/vt-d: Enhance intel_irq_remapping driver to support DMAR unit hotplug"
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On 2014/9/19 13:18, Jiang Liu wrote:
> Implement required callback functions for intel_irq_remapping driver
> to support DMAR unit hotplug.
>
> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>

Reviewed-by: Yijing Wang <wangyijing@xxxxxxxxxx>

> ---
> drivers/iommu/intel_irq_remapping.c | 226 ++++++++++++++++++++++++++---------
> 1 file changed, 171 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
> index 9b140ed854ec..1edbbed8c6bc 100644
> --- a/drivers/iommu/intel_irq_remapping.c
> +++ b/drivers/iommu/intel_irq_remapping.c
> @@ -36,7 +36,6 @@ struct hpet_scope {
>
> static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
> static struct hpet_scope ir_hpet[MAX_HPET_TBS];
> -static int ir_ioapic_num, ir_hpet_num;
>
> /*
> * Lock ordering:
> @@ -206,7 +205,7 @@ 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)
> + if (ir_hpet[i].id == hpet_id && ir_hpet[i].iommu)
> return ir_hpet[i].iommu;
> return NULL;
> }
> @@ -216,7 +215,7 @@ 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)
> + if (ir_ioapic[i].id == apic && ir_ioapic[i].iommu)
> return ir_ioapic[i].iommu;
> return NULL;
> }
> @@ -325,7 +324,7 @@ static int set_ioapic_sid(struct irte *irte, int apic)
>
> down_read(&dmar_global_lock);
> for (i = 0; i < MAX_IO_APICS; i++) {
> - if (ir_ioapic[i].id == apic) {
> + if (ir_ioapic[i].iommu && ir_ioapic[i].id == apic) {
> sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn;
> break;
> }
> @@ -352,7 +351,7 @@ static int set_hpet_sid(struct irte *irte, u8 id)
>
> down_read(&dmar_global_lock);
> for (i = 0; i < MAX_HPET_TBS; i++) {
> - if (ir_hpet[i].id == id) {
> + if (ir_hpet[i].iommu && ir_hpet[i].id == id) {
> sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn;
> break;
> }
> @@ -474,17 +473,17 @@ static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
> raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
> }
>
> -
> -static int intel_setup_irq_remapping(struct intel_iommu *iommu, int mode)
> +static int intel_setup_irq_remapping(struct intel_iommu *iommu)
> {
> struct ir_table *ir_table;
> struct page *pages;
> unsigned long *bitmap;
>
> - ir_table = iommu->ir_table = kzalloc(sizeof(struct ir_table),
> - GFP_ATOMIC);
> + if (iommu->ir_table)
> + return 0;
>
> - if (!iommu->ir_table)
> + ir_table = kzalloc(sizeof(struct ir_table), GFP_ATOMIC);
> + if (!ir_table)
> return -ENOMEM;
>
> pages = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
> @@ -493,7 +492,7 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu, int mode)
> if (!pages) {
> pr_err("IR%d: failed to allocate pages of order %d\n",
> iommu->seq_id, INTR_REMAP_PAGE_ORDER);
> - kfree(iommu->ir_table);
> + kfree(ir_table);
> return -ENOMEM;
> }
>
> @@ -508,11 +507,22 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu, int mode)
>
> ir_table->base = page_address(pages);
> ir_table->bitmap = bitmap;
> + iommu->ir_table = ir_table;
>
> - iommu_set_irq_remapping(iommu, mode);
> return 0;
> }
>
> +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.
> */
> @@ -667,9 +677,10 @@ static int __init intel_enable_irq_remapping(void)
> if (!ecap_ir_support(iommu->ecap))
> continue;
>
> - if (intel_setup_irq_remapping(iommu, eim))
> + if (intel_setup_irq_remapping(iommu))
> goto error;
>
> + iommu_set_irq_remapping(iommu, eim);
> setup = 1;
> }
>
> @@ -700,12 +711,13 @@ error:
> return -1;
> }
>
> -static void ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope,
> - struct intel_iommu *iommu)
> +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;
> + int count, free = -1;
>
> bus = scope->bus;
> path = (struct acpi_dmar_pci_path *)(scope + 1);
> @@ -721,19 +733,36 @@ static void ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope,
> PCI_SECONDARY_BUS);
> path++;
> }
> - ir_hpet[ir_hpet_num].bus = bus;
> - ir_hpet[ir_hpet_num].devfn = PCI_DEVFN(path->device, path->function);
> - ir_hpet[ir_hpet_num].iommu = iommu;
> - ir_hpet[ir_hpet_num].id = scope->enumeration_id;
> - ir_hpet_num++;
> +
> + 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 void ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
> - struct intel_iommu *iommu)
> +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;
> + int count, free = -1;
>
> bus = scope->bus;
> path = (struct acpi_dmar_pci_path *)(scope + 1);
> @@ -750,54 +779,63 @@ static void ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
> path++;
> }
>
> - ir_ioapic[ir_ioapic_num].bus = bus;
> - ir_ioapic[ir_ioapic_num].devfn = PCI_DEVFN(path->device, path->function);
> - ir_ioapic[ir_ioapic_num].iommu = iommu;
> - ir_ioapic[ir_ioapic_num].id = scope->enumeration_id;
> - ir_ioapic_num++;
> + 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) {
> + while (start < end && ret == 0) {
> scope = start;
> - if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC) {
> - if (ir_ioapic_num == MAX_IO_APICS) {
> - printk(KERN_WARNING "Exceeded Max IO APICS\n");
> - return -1;
> - }
> -
> - printk(KERN_INFO "IOAPIC id %d under DRHD base "
> - " 0x%Lx IOMMU %d\n", scope->enumeration_id,
> - drhd->address, iommu->seq_id);
> + 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;
> + }
>
> - ir_parse_one_ioapic_scope(scope, iommu);
> - } else if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_HPET) {
> - if (ir_hpet_num == MAX_HPET_TBS) {
> - printk(KERN_WARNING "Exceeded Max HPET blocks\n");
> - return -1;
> - }
> + return ret;
> +}
>
> - printk(KERN_INFO "HPET id %d under DRHD base"
> - " 0x%Lx\n", scope->enumeration_id,
> - drhd->address);
> +static void ir_remove_ioapic_hpet_scope(struct intel_iommu *iommu)
> +{
> + int i;
>
> - ir_parse_one_hpet_scope(scope, iommu);
> - }
> - start += scope->length;
> - }
> + for (i = 0; i < MAX_HPET_TBS; i++)
> + if (ir_hpet[i].iommu == iommu)
> + ir_hpet[i].iommu = NULL;
>
> - return 0;
> + for (i = 0; i < MAX_IO_APICS; i++)
> + if (ir_ioapic[i].iommu == iommu)
> + ir_ioapic[i].iommu = NULL;
> }
>
> /*
> @@ -1173,7 +1211,85 @@ struct irq_remap_ops intel_irq_remap_ops = {
> .setup_hpet_msi = intel_setup_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)
> {
> - return irq_remapping_enabled ? -ENOSYS : 0;
> + 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;
> }
>

--
Thanks!
Yijing

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Next message: Michal Simek: "Re: [PATCH 1/2] devicetree: cadence_ttc: Document binding for timer width"
Previous message: Yijing Wang: "Re: [Patch Part3 V6 1/8] iommu/vt-d: Introduce helper function dmar_walk_resources()"
In reply to: Jiang Liu: "[Patch Part3 V6 5/8] iommu/vt-d: Enhance intel_irq_remapping driver to support DMAR unit hotplug"
Next in thread: Jiang Liu: "[Patch Part3 V6 4/8] iommu/vt-d: Search for ACPI _DSM method for DMAR hotplug"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]