[PATCH v3 11/23] xen/arm: vsmmuv3: Attach Stage-1 configuration to SMMUv3 hardware

Milan Djokic posted 23 patches 1 day, 23 hours ago
[PATCH v3 11/23] xen/arm: vsmmuv3: Attach Stage-1 configuration to SMMUv3 hardware
Posted by Milan Djokic 1 day, 23 hours ago
From: Rahul Singh <rahul.singh@arm.com>

Attach the Stage-1 configuration to device STE to support nested
translation for the guests.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Signed-off-by: Milan Djokic <milan_djokic@epam.com>
---
 xen/arch/arm/include/asm/iommu.h       |  7 +++
 xen/drivers/passthrough/arm/smmu-v3.c  | 79 ++++++++++++++++++++++++++
 xen/drivers/passthrough/arm/smmu-v3.h  |  1 +
 xen/drivers/passthrough/arm/vsmmu-v3.c | 18 ++++++
 xen/include/xen/iommu.h                |  6 ++
 5 files changed, 111 insertions(+)

diff --git a/xen/arch/arm/include/asm/iommu.h b/xen/arch/arm/include/asm/iommu.h
index ad15477e24..56bc9314a7 100644
--- a/xen/arch/arm/include/asm/iommu.h
+++ b/xen/arch/arm/include/asm/iommu.h
@@ -20,6 +20,13 @@ struct arch_iommu
     void *priv;
 };
 
+struct iommu_guest_config {
+    paddr_t     s1ctxptr;
+    uint8_t     config;
+    uint8_t     s1fmt;
+    uint8_t     s1cdmax;
+};
+
 const struct iommu_ops *iommu_get_ops(void);
 void iommu_set_ops(const struct iommu_ops *ops);
 
diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index 87612df21d..cf8f638a49 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -2810,6 +2810,37 @@ static struct arm_smmu_device *arm_smmu_get_by_dev(const struct device *dev)
 	return NULL;
 }
 
+static struct iommu_domain *arm_smmu_get_domain_by_sid(struct domain *d,
+				u32 sid)
+{
+	int i;
+	unsigned long flags;
+	struct iommu_domain *io_domain;
+	struct arm_smmu_domain *smmu_domain;
+	struct arm_smmu_master *master;
+	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
+
+	/*
+	 * Loop through the &xen_domain->contexts to locate a context
+	 * assigned to this SMMU
+	 */
+	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
+		smmu_domain = to_smmu_domain(io_domain);
+
+		spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+		list_for_each_entry(master, &smmu_domain->devices, domain_head) {
+			for (i = 0; i < master->num_streams; i++) {
+				if (sid != master->streams[i].id)
+					continue;
+				spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+				return io_domain;
+			}
+		}
+		spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+	}
+	return NULL;
+}
+
 static struct iommu_domain *arm_smmu_get_domain(struct domain *d,
 				struct device *dev)
 {
@@ -3022,6 +3053,53 @@ static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
 	xfree(xen_domain);
 }
 
+static int arm_smmu_attach_guest_config(struct domain *d, u32 sid,
+		struct iommu_guest_config *cfg)
+{
+	int ret = -EINVAL;
+	unsigned long flags;
+	struct arm_smmu_master *master;
+	struct arm_smmu_domain *smmu_domain;
+	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
+	struct iommu_domain *io_domain = arm_smmu_get_domain_by_sid(d, sid);
+
+	if (!io_domain)
+		return -ENODEV;
+
+	smmu_domain = to_smmu_domain(io_domain);
+
+	spin_lock(&xen_domain->lock);
+
+	switch (cfg->config) {
+	case ARM_SMMU_DOMAIN_ABORT:
+		smmu_domain->abort = true;
+		break;
+	case ARM_SMMU_DOMAIN_BYPASS:
+		smmu_domain->abort = false;
+		break;
+	case ARM_SMMU_DOMAIN_NESTED:
+		/* Enable Nested stage translation. */
+		smmu_domain->stage = ARM_SMMU_DOMAIN_NESTED;
+		smmu_domain->s1_cfg.s1ctxptr = cfg->s1ctxptr;
+		smmu_domain->s1_cfg.s1fmt = cfg->s1fmt;
+		smmu_domain->s1_cfg.s1cdmax = cfg->s1cdmax;
+		smmu_domain->abort = false;
+		break;
+	default:
+		goto out;
+	}
+
+	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+	list_for_each_entry(master, &smmu_domain->devices, domain_head)
+		arm_smmu_install_ste_for_dev(master);
+	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+
+	ret = 0;
+out:
+	spin_unlock(&xen_domain->lock);
+	return ret;
+}
+
 static const struct iommu_ops arm_smmu_iommu_ops = {
 	.page_sizes		= PAGE_SIZE_4K,
 	.init			= arm_smmu_iommu_xen_domain_init,
@@ -3034,6 +3112,7 @@ static const struct iommu_ops arm_smmu_iommu_ops = {
 	.unmap_page		= arm_iommu_unmap_page,
 	.dt_xlate		= arm_smmu_dt_xlate,
 	.add_device		= arm_smmu_add_device,
+	.attach_guest_config = arm_smmu_attach_guest_config
 };
 
 static __init int arm_smmu_dt_init(struct dt_device_node *dev,
diff --git a/xen/drivers/passthrough/arm/smmu-v3.h b/xen/drivers/passthrough/arm/smmu-v3.h
index fab4fd5a26..df3b7ec1b5 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.h
+++ b/xen/drivers/passthrough/arm/smmu-v3.h
@@ -398,6 +398,7 @@ enum arm_smmu_domain_stage {
 	ARM_SMMU_DOMAIN_S2,
 	ARM_SMMU_DOMAIN_NESTED,
 	ARM_SMMU_DOMAIN_BYPASS,
+	ARM_SMMU_DOMAIN_ABORT,
 };
 
 /* Xen specific code. */
diff --git a/xen/drivers/passthrough/arm/vsmmu-v3.c b/xen/drivers/passthrough/arm/vsmmu-v3.c
index 39ed4dc577..6d3636b18b 100644
--- a/xen/drivers/passthrough/arm/vsmmu-v3.c
+++ b/xen/drivers/passthrough/arm/vsmmu-v3.c
@@ -224,8 +224,11 @@ static int arm_vsmmu_handle_cfgi_ste(struct virt_smmu *smmu, uint64_t *cmdptr)
 {
     int ret;
     uint64_t ste[STRTAB_STE_DWORDS];
+    struct domain *d = smmu->d;
+    struct domain_iommu *hd = dom_iommu(d);
     struct arm_vsmmu_s1_trans_cfg s1_cfg = {0};
     uint32_t sid = smmu_cmd_get_sid(cmdptr[0]);
+    struct iommu_guest_config guest_cfg = {0};
 
     ret = arm_vsmmu_find_ste(smmu, sid, ste);
     if ( ret )
@@ -235,6 +238,21 @@ static int arm_vsmmu_handle_cfgi_ste(struct virt_smmu *smmu, uint64_t *cmdptr)
     if ( ret )
         return (ret == -EAGAIN ) ? 0 : ret;
 
+    guest_cfg.s1ctxptr = s1_cfg.s1ctxptr;
+    guest_cfg.s1fmt = s1_cfg.s1fmt;
+    guest_cfg.s1cdmax = s1_cfg.s1cdmax;
+
+    if ( s1_cfg.bypassed )
+        guest_cfg.config = ARM_SMMU_DOMAIN_BYPASS;
+    else if ( s1_cfg.aborted )
+        guest_cfg.config = ARM_SMMU_DOMAIN_ABORT;
+    else
+        guest_cfg.config = ARM_SMMU_DOMAIN_NESTED;
+
+    ret = hd->platform_ops->attach_guest_config(d, sid, &guest_cfg);
+    if ( ret )
+        return ret;
+
     return 0;
 }
 
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 37c4a1dc82..19e59095c3 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -312,6 +312,7 @@ static inline int iommu_add_dt_pci_sideband_ids(struct pci_dev *pdev)
 #endif /* HAS_DEVICE_TREE_DISCOVERY */
 
 struct page_info;
+struct iommu_guest_config;
 
 /*
  * Any non-zero value returned from callbacks of this type will cause the
@@ -387,6 +388,11 @@ struct iommu_ops {
 #endif
     /* Inhibit all interrupt generation, to be used at shutdown. */
     void (*quiesce)(void);
+
+#ifdef CONFIG_ARM
+    int (*attach_guest_config)(struct domain *d, u32 sid,
+                               struct iommu_guest_config *cfg);
+#endif
 };
 
 /*
-- 
2.43.0
Re: [PATCH v3 11/23] xen/arm: vsmmuv3: Attach Stage-1 configuration to SMMUv3 hardware
Posted by Jan Beulich 1 day, 17 hours ago
On 31.03.2026 03:52, Milan Djokic wrote:
> --- a/xen/include/xen/iommu.h
> +++ b/xen/include/xen/iommu.h
> @@ -312,6 +312,7 @@ static inline int iommu_add_dt_pci_sideband_ids(struct pci_dev *pdev)
>  #endif /* HAS_DEVICE_TREE_DISCOVERY */
>  
>  struct page_info;
> +struct iommu_guest_config;
>  
>  /*
>   * Any non-zero value returned from callbacks of this type will cause the
> @@ -387,6 +388,11 @@ struct iommu_ops {
>  #endif
>      /* Inhibit all interrupt generation, to be used at shutdown. */
>      void (*quiesce)(void);
> +
> +#ifdef CONFIG_ARM
> +    int (*attach_guest_config)(struct domain *d, u32 sid,

Nit: uint32_t please, provided a fixed-width type is actually warranted here
(see ./CODING_STYLE).

> +                               struct iommu_guest_config *cfg);

Pointer-to-const?

Jan