[v9 0/9] Add VT-d Posted-Interrupts support - IOMMU part

[v9 0/9] Add VT-d Posted-Interrupts support - IOMMU part

[Feng Wu]

VT-d Posted-Interrupts is an enhancement to CPU side Posted-Interrupt.
With VT-d Posted-Interrupts enabled, external interrupts from
direct-assigned devices can be delivered to guests without VMM
intervention when guest is running in non-root mode.

You can find the VT-d Posted-Interrtups Spec. in the following URL:
http://www.intel.com/content/www/us/en/intelligent-systems/intel-technology/vt-directed-io-spec.html

This series was part of http://thread.gmane.org/gmane.linux.kernel.iommu/7708. To make things clear, send out IOMMU part here.

This patch-set is based on the lastest x86/apic branch of tip tree.

Divide the whole series which contain multiple components into three parts:
- Prerequisite changes to irq subsystem (already merged in tip tree x86/apic branch)
- IOMMU part (in this series)
- KVM and VFIO parts (will send out this part once the first two parts are accepted)

v8->v9:
* Remove member "irte_pi_entry" in struct intel_ir_data.
* Some changes to the comments.

v7->v8:
* Save the irq mode (posted or remapped) of an IRTE in struct irq_2_iommu.
* Use this new mode to decide whether update the hardware when
modifying irte in intel_ir_set_affinity().

v6->v7:
* Add an static inline helper function set_irq_posting_cap() to set
the PI capability.
* Add some comments for the new member "ir_data->irte_pi_entry".

v5->v6:
* Extend 'struct irte' for VT-d Posted-Interrupts, combine remapped
and posted mode into one irte structure.

v4->v5:
* Abstract modify_irte() to accept two format of irte.

v3->v4:
* Change capability to a int variant flags instead of a function call.
* Add hotplug case for VT-d PI.

Feng Wu (8):
  iommu: Add new member capability to struct irq_remap_ops
  iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
  iommu, x86: Save the mode (posted or remapped) of an IRTE
  iommu, x86: No need to migrating irq for VT-d Posted-Interrupts
  iommu, x86: Add cap_pi_support() to detect VT-d PI capability
  iommu, x86: Setup Posted-Interrupts capability for Intel iommu
  iommu, x86: define irq_remapping_cap()
  iommu, x86: Properly handler PI for IOMMU hotplug

Thomas Gleixner (1):
  iommu: dmar: Extend struct irte for VT-d Posted-Interrupts

 arch/x86/include/asm/irq_remapping.h | 11 +++++
 drivers/iommu/intel_irq_remapping.c  | 90 +++++++++++++++++++++++++++++++++++-
 drivers/iommu/irq_remapping.c        | 11 +++++
 drivers/iommu/irq_remapping.h        |  6 +++
 include/linux/dmar.h                 | 70 ++++++++++++++++++++++------
 include/linux/intel-iommu.h          |  1 +
 6 files changed, 173 insertions(+), 16 deletions(-)

-- 
2.1.0

[v9 1/9] iommu: Add new member capability to struct irq_remap_ops

[Feng Wu]

This patch adds a new member capability to struct irq_remap_ops,
this new function ops can be used to check whether some
features are supported, such as VT-d Posted-Interrupts.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
---
 arch/x86/include/asm/irq_remapping.h | 4 ++++
 drivers/iommu/irq_remapping.h        | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 78974fb..0953723 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -31,6 +31,10 @@ struct irq_alloc_info;
 
 #ifdef CONFIG_IRQ_REMAP
 
+enum irq_remap_cap {
+	IRQ_POSTING_CAP = 0,
+};
+
 extern void set_irq_remapping_broken(void);
 extern int irq_remapping_prepare(void);
 extern int irq_remapping_enable(void);
diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h
index 91d5a11..b6ca30d 100644
--- a/drivers/iommu/irq_remapping.h
+++ b/drivers/iommu/irq_remapping.h
@@ -35,6 +35,9 @@ extern int no_x2apic_optout;
 extern int irq_remapping_enabled;
 
 struct irq_remap_ops {
+	/* The supported capabilities */
+	int capability;
+
 	/* Initializes hardware and makes it ready for remapping interrupts */
 	int  (*prepare)(void);
 
-- 
2.1.0

[v9 2/9] iommu: dmar: Extend struct irte for VT-d Posted-Interrupts

[Feng Wu]

From: Thomas Gleixner <tglx@linutronix.de>

The IRTE (Interrupt Remapping Table Entry) is either an entry for
remapped or for posted interrupts. The hardware distiguishes between
remapped and posted entries by bit 15 in the low 64 bit of the
IRTE. If cleared the entry is remapped, if set it's posted.

The entries have common fields and dependent on the posted bit fields
with different meanings.

Extend struct irte to handle the differences between remap and posted
mode by having three structs in the unions:

	- Shared
	- Remapped
	- Posted

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Feng Wu <feng.wu@intel.com>
---
 include/linux/dmar.h | 70 +++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 55 insertions(+), 15 deletions(-)

diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index 8473756..0dbcabc 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -185,33 +185,73 @@ static inline int dmar_device_remove(void *handle)
 
 struct irte {
 	union {
+		/* Shared between remapped and posted mode*/
 		struct {
-			__u64	present 	: 1,
-				fpd		: 1,
-				dst_mode	: 1,
-				redir_hint	: 1,
-				trigger_mode	: 1,
-				dlvry_mode	: 3,
-				avail		: 4,
-				__reserved_1	: 4,
-				vector		: 8,
-				__reserved_2	: 8,
-				dest_id		: 32;
+			__u64	present		: 1,  /*  0      */
+				fpd		: 1,  /*  1      */
+				__res0		: 6,  /*  2 -  6 */
+				avail		: 4,  /*  8 - 11 */
+				__res1		: 3,  /* 12 - 14 */
+				pst		: 1,  /* 15      */
+				vector		: 8,  /* 16 - 23 */
+				__res2		: 40; /* 24 - 63 */
+		};
+
+		/* Remapped mode */
+		struct {
+			__u64	r_present	: 1,  /*  0      */
+				r_fpd		: 1,  /*  1      */
+				dst_mode	: 1,  /*  2      */
+				redir_hint	: 1,  /*  3      */
+				trigger_mode	: 1,  /*  4      */
+				dlvry_mode	: 3,  /*  5 -  7 */
+				r_avail		: 4,  /*  8 - 11 */
+				r_res0		: 4,  /* 12 - 15 */
+				r_vector	: 8,  /* 16 - 23 */
+				r_res1		: 8,  /* 24 - 31 */
+				dest_id		: 32; /* 32 - 63 */
+		};
+
+		/* Posted mode */
+		struct {
+			__u64	p_present	: 1,  /*  0      */
+				p_fpd		: 1,  /*  1      */
+				p_res0		: 6,  /*  2 -  7 */
+				p_avail		: 4,  /*  8 - 11 */
+				p_res1		: 2,  /* 12 - 13 */
+				p_urgent	: 1,  /* 14      */
+				p_pst		: 1,  /* 15      */
+				p_vector	: 8,  /* 16 - 23 */
+				p_res2		: 14, /* 24 - 37 */
+				pda_l		: 26; /* 38 - 63 */
 		};
 		__u64 low;
 	};
 
 	union {
+		/* Shared between remapped and posted mode*/
 		struct {
-			__u64	sid		: 16,
-				sq		: 2,
-				svt		: 2,
-				__reserved_3	: 44;
+			__u64	sid		: 16,  /* 64 - 79  */
+				sq		: 2,   /* 80 - 81  */
+				svt		: 2,   /* 82 - 83  */
+				__res3		: 44;  /* 84 - 127 */
+		};
+
+		/* Posted mode*/
+		struct {
+			__u64	p_sid		: 16,  /* 64 - 79  */
+				p_sq		: 2,   /* 80 - 81  */
+				p_svt		: 2,   /* 82 - 83  */
+				p_res3		: 12,  /* 84 - 95  */
+				pda_h		: 32;  /* 96 - 127 */
 		};
 		__u64 high;
 	};
 };
 
+#define PDA_LOW_BIT    26
+#define PDA_HIGH_BIT   32
+
 enum {
 	IRQ_REMAP_XAPIC_MODE,
 	IRQ_REMAP_X2APIC_MODE,
-- 
2.1.0

[v9 3/9] iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip

[Feng Wu]

Implement irq_set_vcpu_affinity for intel_ir_chip.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
---
 arch/x86/include/asm/irq_remapping.h |  5 +++++
 drivers/iommu/intel_irq_remapping.c  | 43 ++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+)

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 0953723..202e040 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -57,6 +57,11 @@ static inline struct irq_domain *arch_get_ir_parent_domain(void)
 	return x86_vector_domain;
 }
 
+struct vcpu_data {
+	u64 pi_desc_addr;	/* Physical address of PI Descriptor */
+	u32 vector;		/* Guest vector of the interrupt */
+};
+
 #else  /* CONFIG_IRQ_REMAP */
 
 static inline void set_irq_remapping_broken(void) { }
diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 8fad71c..9bbc235 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1013,10 +1013,53 @@ static void intel_ir_compose_msi_msg(struct irq_data *irq_data,
 	*msg = ir_data->msi_entry;
 }
 
+static int intel_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
+{
+	struct intel_ir_data *ir_data = data->chip_data;
+	struct irte irte_pi;
+	struct vcpu_data *vcpu_pi_info;
+
+	/* stop posting interrupts, back to remapping mode */
+	if (!vcpu_info) {
+		modify_irte(&ir_data->irq_2_iommu, &ir_data->irte_entry);
+	} else {
+		vcpu_pi_info = (struct vcpu_data *)vcpu_info;
+
+		/*
+		 * "ir_data->irte_entry" saves the remapped format of IRTE,
+		 * which being a cached irte is still updated when setting
+		 * the affinity even when we are in posted mode. So this makes
+		 * it possible to switch back to remapped mode from posted mode,
+		 * we can just set "ir_data->irte_entry" to hardware for that
+		 * purpose.
+		 */
+		memcpy(&irte_pi, &ir_data->irte_entry, sizeof(struct irte));
+
+		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);
+
+		irte_pi.p_res0 = 0;
+		irte_pi.p_res1 = 0;
+		irte_pi.p_res2 = 0;
+		irte_pi.p_res3 = 0;
+
+		irte_pi.p_pst = 1;
+
+		modify_irte(&ir_data->irq_2_iommu, &irte_pi);
+	}
+
+	return 0;
+}
+
 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,
+	.irq_set_vcpu_affinity = intel_ir_set_vcpu_affinity,
 };
 
 static void intel_irq_remapping_prepare_irte(struct intel_ir_data *data,
-- 
2.1.0

[v9 4/9] iommu, x86: Save the mode (posted or remapped) of an IRTE

[Feng Wu]

This patch adds a new field in struct irq_2_iommu, which can
capture whether the entry is in posted mode or remapped mode.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
---
 drivers/iommu/intel_irq_remapping.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 9bbc235..028d628 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -18,6 +18,11 @@
 
 #include "irq_remapping.h"
 
+enum irq_mode {
+	IRQ_REMAPPING,
+	IRQ_POSTING,
+};
+
 struct ioapic_scope {
 	struct intel_iommu *iommu;
 	unsigned int id;
@@ -37,6 +42,7 @@ struct irq_2_iommu {
 	u16 irte_index;
 	u16 sub_handle;
 	u8  irte_mask;
+	enum irq_mode mode;
 };
 
 struct intel_ir_data {
@@ -104,6 +110,7 @@ static int alloc_irte(struct intel_iommu *iommu, int irq,
 		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);
 
@@ -144,6 +151,8 @@ static int modify_irte(struct irq_2_iommu *irq_iommu,
 	__iommu_flush_cache(iommu, irte, sizeof(*irte));
 
 	rc = qi_flush_iec(iommu, index, 0);
+
+	irq_iommu->mode = irte->pst ? IRQ_POSTING : IRQ_REMAPPING;
 	raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
 
 	return rc;
-- 
2.1.0

[v9 5/9] iommu, x86: No need to migrating irq for VT-d Posted-Interrupts

[Feng Wu]

We don't need to migrate the irqs for VT-d Posted-Interrupts here.
When 'pst' is set in IRTE, the associated irq will be posted to
guests instead of interrupt remapping. The destination of the
interrupt is set in Posted-Interrupts Descriptor, and the migration
happens during vCPU scheduling.

However, we still update the cached irte here, which can be used
when changing back to remapping mode.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
---
 drivers/iommu/intel_irq_remapping.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 028d628..c30845a 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1002,7 +1002,10 @@ intel_ir_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	 */
 	irte->vector = cfg->vector;
 	irte->dest_id = IRTE_DEST(cfg->dest_apicid);
-	modify_irte(&ir_data->irq_2_iommu, irte);
+
+	/* Update the hardware only if the interrupt is in remapped mode. */
+	if (ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
+		modify_irte(&ir_data->irq_2_iommu, irte);
 
 	/*
 	 * After this point, all the interrupts will start arriving
-- 
2.1.0

[v9 6/9] iommu, x86: Add cap_pi_support() to detect VT-d PI capability

[Feng Wu]

Add helper function to detect VT-d Posted-Interrupts capability.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
---
 include/linux/intel-iommu.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 0af9b03..0c251be 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -87,6 +87,7 @@ static inline void dmar_writeq(void __iomem *addr, u64 val)
 /*
  * Decoding Capability Register
  */
+#define cap_pi_support(c)	(((c) >> 59) & 1)
 #define cap_read_drain(c)	(((c) >> 55) & 1)
 #define cap_write_drain(c)	(((c) >> 54) & 1)
 #define cap_max_amask_val(c)	(((c) >> 48) & 0x3f)
-- 
2.1.0

[v9 7/9] iommu, x86: Setup Posted-Interrupts capability for Intel iommu

[Feng Wu]

Set Posted-Interrupts capability for Intel iommu when IR is enabled,
clear it when IR is disabled.

Signed-off-by: Feng Wu <feng.wu@intel.com>
---
 drivers/iommu/intel_irq_remapping.c | 30 ++++++++++++++++++++++++++++++
 drivers/iommu/irq_remapping.c       |  2 ++
 drivers/iommu/irq_remapping.h       |  3 +++
 3 files changed, 35 insertions(+)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index c30845a..554e203 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -580,6 +580,26 @@ error:
 	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) {
+		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;
@@ -655,6 +675,8 @@ static int __init intel_enable_irq_remapping(void)
 
 	irq_remapping_enabled = 1;
 
+	set_irq_posting_cap();
+
 	pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
 
 	return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
@@ -855,6 +877,12 @@ static void disable_irq_remapping(void)
 
 		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)
@@ -882,6 +910,8 @@ static int reenable_irq_remapping(int eim)
 	if (!setup)
 		goto error;
 
+	set_irq_posting_cap();
+
 	return 0;
 
 error:
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index fc78b0d..ed605a9 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -22,6 +22,8 @@ int irq_remap_broken;
 int disable_sourceid_checking;
 int no_x2apic_optout;
 
+int disable_irq_post = 1;
+
 static int disable_irq_remap;
 static struct irq_remap_ops *remap_ops;
 
diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h
index b6ca30d..039c7af 100644
--- a/drivers/iommu/irq_remapping.h
+++ b/drivers/iommu/irq_remapping.h
@@ -34,6 +34,8 @@ extern int disable_sourceid_checking;
 extern int no_x2apic_optout;
 extern int irq_remapping_enabled;
 
+extern int disable_irq_post;
+
 struct irq_remap_ops {
 	/* The supported capabilities */
 	int capability;
@@ -69,6 +71,7 @@ extern void ir_ack_apic_edge(struct irq_data *data);
 
 #define irq_remapping_enabled 0
 #define irq_remap_broken      0
+#define disable_irq_post      1
 
 #endif /* CONFIG_IRQ_REMAP */
 
-- 
2.1.0

[v9 8/9] iommu, x86: define irq_remapping_cap()

[Feng Wu]

This patch adds a new interface irq_remapping_cap() to detect
whether irq remapping supports new features, such as VT-d
Posted-Interrupts. We export this function out, so that KVM
code can check this and use this mechanism properly.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
---
 arch/x86/include/asm/irq_remapping.h | 2 ++
 drivers/iommu/irq_remapping.c        | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 202e040..61aa8ad 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -35,6 +35,7 @@ enum irq_remap_cap {
 	IRQ_POSTING_CAP = 0,
 };
 
+extern bool irq_remapping_cap(enum irq_remap_cap cap);
 extern void set_irq_remapping_broken(void);
 extern int irq_remapping_prepare(void);
 extern int irq_remapping_enable(void);
@@ -64,6 +65,7 @@ struct vcpu_data {
 
 #else  /* CONFIG_IRQ_REMAP */
 
+static bool irq_remapping_cap(enum irq_remap_cap cap) { return 0; }
 static inline void set_irq_remapping_broken(void) { }
 static inline int irq_remapping_prepare(void) { return -ENODEV; }
 static inline int irq_remapping_enable(void) { return -ENODEV; }
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index ed605a9..2d99930 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -81,6 +81,15 @@ void set_irq_remapping_broken(void)
 	irq_remap_broken = 1;
 }
 
+bool irq_remapping_cap(enum irq_remap_cap cap)
+{
+	if (!remap_ops || disable_irq_post)
+		return 0;
+
+	return (remap_ops->capability & (1 << cap));
+}
+EXPORT_SYMBOL_GPL(irq_remapping_cap);
+
 int __init irq_remapping_prepare(void)
 {
 	if (disable_irq_remap)
-- 
2.1.0

[v9 9/9] iommu, x86: Properly handler PI for IOMMU hotplug

[Feng Wu]

Return error when inserting a new IOMMU which doesn't support PI
if PI is currently in use.

Signed-off-by: Feng Wu <feng.wu@intel.com>
---
 drivers/iommu/intel_irq_remapping.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 554e203..4fb3576 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1360,6 +1360,9 @@ int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert)
 		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)
-- 
2.1.0

Re: [v9 0/9] Add VT-d Posted-Interrupts support - IOMMU part

[Thomas Gleixner]

On Fri, 5 Jun 2015, Feng Wu wrote:
> Divide the whole series which contain multiple components into three parts:
> - Prerequisite changes to irq subsystem (already merged in tip tree x86/apic branch)
> - IOMMU part (in this series)

Please add 

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>

Which tree should this go through? It depends on tip/x86/apic AFAICT,
so we can take it through that, if Joerg provides his ACK.

Thanks,

	tglx
 

Re: [v9 0/9] Add VT-d Posted-Interrupts support - IOMMU part

[Joerg Roedel]

On Fri, Jun 05, 2015 at 01:47:06PM +0200, Thomas Gleixner wrote:
> On Fri, 5 Jun 2015, Feng Wu wrote:
> > Divide the whole series which contain multiple components into three parts:
> > - Prerequisite changes to irq subsystem (already merged in tip tree x86/apic branch)
> > - IOMMU part (in this series)
> 
> Please add 
> 
> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
> 
> Which tree should this go through? It depends on tip/x86/apic AFAICT,
> so we can take it through that, if Joerg provides his ACK.

Yeah, these changes depend on tip/x86/apic, so it doesn't make sense to
send them through the iommu tree. There will be some conflicts when
merging tip/x86/apic and the iommu tree together, though, mainly because
of the vt-d kdump fixing patches I have in my tree. The conflicts are
spread over 3 files, but not too serious and easy to resolve.

Anyway, you have my

Acked-by: Joerg Roedel <jroedel@suse.de>

for those.


	Joerg

RE: [v9 0/9] Add VT-d Posted-Interrupts support - IOMMU part

[Wu, Feng]

> -----Original Message-----
> From: Joerg Roedel [mailto:joro@8bytes.org]
> Sent: Friday, June 05, 2015 9:34 PM
> To: Thomas Gleixner
> Cc: Wu, Feng; dwmw2@infradead.org; jiang.liu@linux.intel.com;
> iommu@lists.linux-foundation.org; linux-kernel@vger.kernel.org
> Subject: Re: [v9 0/9] Add VT-d Posted-Interrupts support - IOMMU part
> 
> On Fri, Jun 05, 2015 at 01:47:06PM +0200, Thomas Gleixner wrote:
> > On Fri, 5 Jun 2015, Feng Wu wrote:
> > > Divide the whole series which contain multiple components into three
> parts:
> > > - Prerequisite changes to irq subsystem (already merged in tip tree x86/apic
> branch)
> > > - IOMMU part (in this series)
> >
> > Please add
> >
> > Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
> >
> > Which tree should this go through? It depends on tip/x86/apic AFAICT,
> > so we can take it through that, if Joerg provides his ACK.
> 
> Yeah, these changes depend on tip/x86/apic, so it doesn't make sense to
> send them through the iommu tree. There will be some conflicts when
> merging tip/x86/apic and the iommu tree together, though, mainly because
> of the vt-d kdump fixing patches I have in my tree. The conflicts are
> spread over 3 files, but not too serious and easy to resolve.
> 
> Anyway, you have my
> 
> Acked-by: Joerg Roedel <jroedel@suse.de>
> 
> for those.
> 

Hi Joerg,

Thanks for your ACK on this series!

Hi Thomas,

Thanks a lot for your review!

Do you need me to send another version which adds the reviewed-by and acked-by tags,
or you can do it yourself on this version and merge it to tip/x86/apic?

Thanks,
Feng

> 
> 	Joerg

[tip:x86/apic] iommu: Add new member capability to struct irq_remap_ops

[tip-bot for Feng Wu]

Commit-ID:  80e7935bc4b6b2c9d2d5719d41b42e22f5ce92d8
Gitweb:     http://git.kernel.org/tip/80e7935bc4b6b2c9d2d5719d41b42e22f5ce92d8
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:46 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:32 +0200

iommu: Add new member capability to struct irq_remap_ops

Adds a new member 'capability' to struct irq_remap_ops for storing
information about available capabilities such as VT-d
Posted-Interrupts.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-2-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/include/asm/irq_remapping.h | 4 ++++
 drivers/iommu/irq_remapping.h        | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 78974fb..0953723 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -31,6 +31,10 @@ struct irq_alloc_info;
 
 #ifdef CONFIG_IRQ_REMAP
 
+enum irq_remap_cap {
+	IRQ_POSTING_CAP = 0,
+};
+
 extern void set_irq_remapping_broken(void);
 extern int irq_remapping_prepare(void);
 extern int irq_remapping_enable(void);
diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h
index 91d5a11..b6ca30d 100644
--- a/drivers/iommu/irq_remapping.h
+++ b/drivers/iommu/irq_remapping.h
@@ -35,6 +35,9 @@ extern int no_x2apic_optout;
 extern int irq_remapping_enabled;
 
 struct irq_remap_ops {
+	/* The supported capabilities */
+	int capability;
+
 	/* Initializes hardware and makes it ready for remapping interrupts */
 	int  (*prepare)(void);
 

[tip:x86/apic] iommu: dmar: Extend struct irte for VT-d Posted-Interrupts

[tip-bot for Thomas Gleixner]

Commit-ID:  7b7ebe806852e91bbdba33313394fd946d0a22fe
Gitweb:     http://git.kernel.org/tip/7b7ebe806852e91bbdba33313394fd946d0a22fe
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Fri, 5 Jun 2015 13:42:47 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:32 +0200

iommu: dmar: Extend struct irte for VT-d Posted-Interrupts

The IRTE (Interrupt Remapping Table Entry) is either an entry for
remapped or for posted interrupts. The hardware distiguishes between
remapped and posted entries by bit 15 in the low 64 bit of the
IRTE. If cleared the entry is remapped, if set it's posted.

The entries have common fields and dependent on the posted bit fields
with different meanings.

Extend struct irte to handle the differences between remap and posted
mode by having three structs in the unions:

	- Shared
	- Remapped
	- Posted

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Feng Wu <feng.wu@intel.com>
Cc: jiang.liu@linux.intel.com
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-3-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 include/linux/dmar.h | 70 +++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 55 insertions(+), 15 deletions(-)

diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index 8473756..0dbcabc 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -185,33 +185,73 @@ static inline int dmar_device_remove(void *handle)
 
 struct irte {
 	union {
+		/* Shared between remapped and posted mode*/
 		struct {
-			__u64	present 	: 1,
-				fpd		: 1,
-				dst_mode	: 1,
-				redir_hint	: 1,
-				trigger_mode	: 1,
-				dlvry_mode	: 3,
-				avail		: 4,
-				__reserved_1	: 4,
-				vector		: 8,
-				__reserved_2	: 8,
-				dest_id		: 32;
+			__u64	present		: 1,  /*  0      */
+				fpd		: 1,  /*  1      */
+				__res0		: 6,  /*  2 -  6 */
+				avail		: 4,  /*  8 - 11 */
+				__res1		: 3,  /* 12 - 14 */
+				pst		: 1,  /* 15      */
+				vector		: 8,  /* 16 - 23 */
+				__res2		: 40; /* 24 - 63 */
+		};
+
+		/* Remapped mode */
+		struct {
+			__u64	r_present	: 1,  /*  0      */
+				r_fpd		: 1,  /*  1      */
+				dst_mode	: 1,  /*  2      */
+				redir_hint	: 1,  /*  3      */
+				trigger_mode	: 1,  /*  4      */
+				dlvry_mode	: 3,  /*  5 -  7 */
+				r_avail		: 4,  /*  8 - 11 */
+				r_res0		: 4,  /* 12 - 15 */
+				r_vector	: 8,  /* 16 - 23 */
+				r_res1		: 8,  /* 24 - 31 */
+				dest_id		: 32; /* 32 - 63 */
+		};
+
+		/* Posted mode */
+		struct {
+			__u64	p_present	: 1,  /*  0      */
+				p_fpd		: 1,  /*  1      */
+				p_res0		: 6,  /*  2 -  7 */
+				p_avail		: 4,  /*  8 - 11 */
+				p_res1		: 2,  /* 12 - 13 */
+				p_urgent	: 1,  /* 14      */
+				p_pst		: 1,  /* 15      */
+				p_vector	: 8,  /* 16 - 23 */
+				p_res2		: 14, /* 24 - 37 */
+				pda_l		: 26; /* 38 - 63 */
 		};
 		__u64 low;
 	};
 
 	union {
+		/* Shared between remapped and posted mode*/
 		struct {
-			__u64	sid		: 16,
-				sq		: 2,
-				svt		: 2,
-				__reserved_3	: 44;
+			__u64	sid		: 16,  /* 64 - 79  */
+				sq		: 2,   /* 80 - 81  */
+				svt		: 2,   /* 82 - 83  */
+				__res3		: 44;  /* 84 - 127 */
+		};
+
+		/* Posted mode*/
+		struct {
+			__u64	p_sid		: 16,  /* 64 - 79  */
+				p_sq		: 2,   /* 80 - 81  */
+				p_svt		: 2,   /* 82 - 83  */
+				p_res3		: 12,  /* 84 - 95  */
+				pda_h		: 32;  /* 96 - 127 */
 		};
 		__u64 high;
 	};
 };
 
+#define PDA_LOW_BIT    26
+#define PDA_HIGH_BIT   32
+
 enum {
 	IRQ_REMAP_XAPIC_MODE,
 	IRQ_REMAP_X2APIC_MODE,

[tip:x86/apic] iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip

[tip-bot for Feng Wu]

Commit-ID:  d6b9ad3ae95f21b92090f484c5629f710424c6e3
Gitweb:     http://git.kernel.org/tip/d6b9ad3ae95f21b92090f484c5629f710424c6e3
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:48 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:32 +0200

iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip

Interrupt chip callback to set the VCPU affinity for posted interrupts.

[ tglx: Use the helper function to copy from the remap irte instead of
  	open coding it. Massage the comment as well ]

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: joro@8bytes.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-4-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/include/asm/irq_remapping.h |  5 +++++
 drivers/iommu/intel_irq_remapping.c  | 37 ++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 0953723..202e040 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -57,6 +57,11 @@ static inline struct irq_domain *arch_get_ir_parent_domain(void)
 	return x86_vector_domain;
 }
 
+struct vcpu_data {
+	u64 pi_desc_addr;	/* Physical address of PI Descriptor */
+	u32 vector;		/* Guest vector of the interrupt */
+};
+
 #else  /* CONFIG_IRQ_REMAP */
 
 static inline void set_irq_remapping_broken(void) { }
diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 8fad71c..a643eec 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1013,10 +1013,47 @@ static void intel_ir_compose_msi_msg(struct irq_data *irq_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 = {
 	.irq_ack = ir_ack_apic_edge,
 	.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,

[tip:x86/apic] iommu, x86: Save the mode (posted or remapped) of an IRTE

[tip-bot for Feng Wu]

Commit-ID:  7737e29368f693c7de97503133d05dc0675a09c0
Gitweb:     http://git.kernel.org/tip/7737e29368f693c7de97503133d05dc0675a09c0
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:49 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:32 +0200

iommu, x86: Save the mode (posted or remapped) of an IRTE

Add a new field to struct irq_2_iommu, which captures whether the
associated IRTE is in posted mode or remapped mode. We update this
field when the IRTE is written into the table.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Feng Wu <feng.wu@intel.com>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: jiang.liu@linux.intel.com
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-5-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 drivers/iommu/intel_irq_remapping.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index a643eec..68bce0a 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -18,6 +18,11 @@
 
 #include "irq_remapping.h"
 
+enum irq_mode {
+	IRQ_REMAPPING,
+	IRQ_POSTING,
+};
+
 struct ioapic_scope {
 	struct intel_iommu *iommu;
 	unsigned int id;
@@ -37,6 +42,7 @@ struct irq_2_iommu {
 	u16 irte_index;
 	u16 sub_handle;
 	u8  irte_mask;
+	enum irq_mode mode;
 };
 
 struct intel_ir_data {
@@ -104,6 +110,7 @@ static int alloc_irte(struct intel_iommu *iommu, int irq,
 		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);
 
@@ -144,6 +151,9 @@ static int modify_irte(struct irq_2_iommu *irq_iommu,
 	__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;

[tip:x86/apic] iommu, x86: Avoid migrating VT-d posted interrupts

[tip-bot for Feng Wu]

Commit-ID:  ad2453cb74dd0e1ba201b449b610557dc7434234
Gitweb:     http://git.kernel.org/tip/ad2453cb74dd0e1ba201b449b610557dc7434234
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:50 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:32 +0200

iommu, x86: Avoid migrating VT-d posted interrupts

When the interrupt is configured in posted mode, the destination of
the interrupt is set in the Posted-Interrupts Descriptor and the
migration of these interrupts happens during vCPU scheduling.

We still update the cached irte, which will be used when changing back
to remapping mode, but we avoid writing the table entry.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-6-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 drivers/iommu/intel_irq_remapping.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 68bce0a..3bcb459 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1003,7 +1003,10 @@ intel_ir_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	 */
 	irte->vector = cfg->vector;
 	irte->dest_id = IRTE_DEST(cfg->dest_apicid);
-	modify_irte(&ir_data->irq_2_iommu, irte);
+
+	/* Update the hardware only if the interrupt is in remapped mode. */
+	if (ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
+		modify_irte(&ir_data->irq_2_iommu, irte);
 
 	/*
 	 * After this point, all the interrupts will start arriving

[tip:x86/apic] iommu, x86: Add cap_pi_support() to detect VT-d PI capability

[tip-bot for Feng Wu]

Commit-ID:  948f4ea26d44a64e315225299155af82e213ebed
Gitweb:     http://git.kernel.org/tip/948f4ea26d44a64e315225299155af82e213ebed
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:51 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:32 +0200

iommu, x86: Add cap_pi_support() to detect VT-d PI capability

Add helper function to detect VT-d Posted-Interrupts capability.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-7-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 include/linux/intel-iommu.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 0af9b03..0c251be 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -87,6 +87,7 @@ static inline void dmar_writeq(void __iomem *addr, u64 val)
 /*
  * Decoding Capability Register
  */
+#define cap_pi_support(c)	(((c) >> 59) & 1)
 #define cap_read_drain(c)	(((c) >> 55) & 1)
 #define cap_write_drain(c)	(((c) >> 54) & 1)
 #define cap_max_amask_val(c)	(((c) >> 48) & 0x3f)

[tip:x86/apic] iommu, x86: Setup Posted-Interrupts capability for Intel iommu

[tip-bot for Feng Wu]

Commit-ID:  01c87cc1d2fc041821a6ff2e489650759116dec6
Gitweb:     http://git.kernel.org/tip/01c87cc1d2fc041821a6ff2e489650759116dec6
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:52 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:32 +0200

iommu, x86: Setup Posted-Interrupts capability for Intel iommu

Set Posted-Interrupts capability for Intel iommu when Interrupt
Remapping is enabled, clear it when disabled.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: jiang.liu@linux.intel.com
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-8-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 drivers/iommu/intel_irq_remapping.c | 30 ++++++++++++++++++++++++++++++
 drivers/iommu/irq_remapping.c       |  2 ++
 drivers/iommu/irq_remapping.h       |  3 +++
 3 files changed, 35 insertions(+)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 3bcb459..0f57af7 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -581,6 +581,26 @@ error:
 	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) {
+		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;
@@ -656,6 +676,8 @@ static int __init intel_enable_irq_remapping(void)
 
 	irq_remapping_enabled = 1;
 
+	set_irq_posting_cap();
+
 	pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
 
 	return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
@@ -856,6 +878,12 @@ static void disable_irq_remapping(void)
 
 		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)
@@ -883,6 +911,8 @@ static int reenable_irq_remapping(int eim)
 	if (!setup)
 		goto error;
 
+	set_irq_posting_cap();
+
 	return 0;
 
 error:
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index fc78b0d..ed605a9 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -22,6 +22,8 @@ int irq_remap_broken;
 int disable_sourceid_checking;
 int no_x2apic_optout;
 
+int disable_irq_post = 1;
+
 static int disable_irq_remap;
 static struct irq_remap_ops *remap_ops;
 
diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h
index b6ca30d..039c7af 100644
--- a/drivers/iommu/irq_remapping.h
+++ b/drivers/iommu/irq_remapping.h
@@ -34,6 +34,8 @@ extern int disable_sourceid_checking;
 extern int no_x2apic_optout;
 extern int irq_remapping_enabled;
 
+extern int disable_irq_post;
+
 struct irq_remap_ops {
 	/* The supported capabilities */
 	int capability;
@@ -69,6 +71,7 @@ extern void ir_ack_apic_edge(struct irq_data *data);
 
 #define irq_remapping_enabled 0
 #define irq_remap_broken      0
+#define disable_irq_post      1
 
 #endif /* CONFIG_IRQ_REMAP */
 

[tip:x86/apic] iommu, x86: Provide irq_remapping_cap() interface

[tip-bot for Feng Wu]

Commit-ID:  1aa9f1afb6814105c9a0b6b17487533fadc0c763
Gitweb:     http://git.kernel.org/tip/1aa9f1afb6814105c9a0b6b17487533fadc0c763
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:53 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:33 +0200

iommu, x86: Provide irq_remapping_cap() interface

Add a new interface irq_remapping_cap() to detect whether irq
remapping supports new features, such as VT-d Posted-Interrupts.

Export the function, so that KVM code can check this and use this
mechanism properly.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-9-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/include/asm/irq_remapping.h | 2 ++
 drivers/iommu/irq_remapping.c        | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 202e040..61aa8ad 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -35,6 +35,7 @@ enum irq_remap_cap {
 	IRQ_POSTING_CAP = 0,
 };
 
+extern bool irq_remapping_cap(enum irq_remap_cap cap);
 extern void set_irq_remapping_broken(void);
 extern int irq_remapping_prepare(void);
 extern int irq_remapping_enable(void);
@@ -64,6 +65,7 @@ struct vcpu_data {
 
 #else  /* CONFIG_IRQ_REMAP */
 
+static bool irq_remapping_cap(enum irq_remap_cap cap) { return 0; }
 static inline void set_irq_remapping_broken(void) { }
 static inline int irq_remapping_prepare(void) { return -ENODEV; }
 static inline int irq_remapping_enable(void) { return -ENODEV; }
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index ed605a9..2d99930 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -81,6 +81,15 @@ void set_irq_remapping_broken(void)
 	irq_remap_broken = 1;
 }
 
+bool irq_remapping_cap(enum irq_remap_cap cap)
+{
+	if (!remap_ops || disable_irq_post)
+		return 0;
+
+	return (remap_ops->capability & (1 << cap));
+}
+EXPORT_SYMBOL_GPL(irq_remapping_cap);
+
 int __init irq_remapping_prepare(void)
 {
 	if (disable_irq_remap)

[tip:x86/apic] iommu, x86: Properly handle posted interrupts for IOMMU hotplug

[tip-bot for Feng Wu]

Commit-ID:  5bce3c4c68c7d86f8742c9e25814238975563bae
Gitweb:     http://git.kernel.org/tip/5bce3c4c68c7d86f8742c9e25814238975563bae
Author:     Feng Wu <feng.wu@intel.com>
AuthorDate: Fri, 5 Jun 2015 13:42:54 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 8 Jun 2015 15:41:33 +0200

iommu, x86: Properly handle posted interrupts for IOMMU hotplug

Return error when inserting a new IOMMU which doesn't support posted
interrupts if posted interrupts are already enabled.

Signed-off-by: Feng Wu <feng.wu@intel.com>
Acked-by: Joerg Roedel <joro@8bytes.org>
Cc: jiang.liu@linux.intel.com
Cc: iommu@lists.linux-foundation.org
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/1433482974-14614-10-git-send-email-feng.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 drivers/iommu/intel_irq_remapping.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 0f57af7..80f1d14 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1355,6 +1355,9 @@ int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert)
 		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)