iommu/vt-d: Parse SATC reporting structure

Software should parse every SATC table and all devices in the tables
reported by the BIOS and keep the information in kernel list for further
reference.

Signed-off-by: Yian Chen <yian.chen@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210203093329.1617808-1-baolu.lu@linux.intel.com
Link: https://lore.kernel.org/r/20210204014401.2846425-7-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

2 files changed, 97 insertions, 0 deletions

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index bd51f33642e0..6b8fce1c85c4 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -526,6 +526,7 @@ dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
 	struct acpi_dmar_reserved_memory *rmrr;
 	struct acpi_dmar_atsr *atsr;
 	struct acpi_dmar_rhsa *rhsa;
+	struct acpi_dmar_satc *satc;
 
 	switch (header->type) {
 	case ACPI_DMAR_TYPE_HARDWARE_UNIT:
@@ -555,6 +556,10 @@ dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
 		/* We don't print this here because we need to sanity-check
 		   it first. So print it in dmar_parse_one_andd() instead. */
 		break;
+	case ACPI_DMAR_TYPE_SATC:
+		satc = container_of(header, struct acpi_dmar_satc, header);
+		pr_info("SATC flags: 0x%x\n", satc->flags);
+		break;
 	}
 }
 
@@ -642,6 +647,7 @@ parse_dmar_table(void)
 		.cb[ACPI_DMAR_TYPE_ROOT_ATS] = &dmar_parse_one_atsr,
 		.cb[ACPI_DMAR_TYPE_HARDWARE_AFFINITY] = &dmar_parse_one_rhsa,
 		.cb[ACPI_DMAR_TYPE_NAMESPACE] = &dmar_parse_one_andd,
+		.cb[ACPI_DMAR_TYPE_SATC] = &dmar_parse_one_satc,
 	};
 
 	/*
@@ -2077,6 +2083,7 @@ static guid_t dmar_hp_guid =
 #define	DMAR_DSM_FUNC_DRHD		1
 #define	DMAR_DSM_FUNC_ATSR		2
 #define	DMAR_DSM_FUNC_RHSA		3
+#define	DMAR_DSM_FUNC_SATC		4
 
 static inline bool dmar_detect_dsm(acpi_handle handle, int func)
 {
@@ -2094,6 +2101,7 @@ static int dmar_walk_dsm_resource(acpi_handle handle, int func,
 		[DMAR_DSM_FUNC_DRHD] = ACPI_DMAR_TYPE_HARDWARE_UNIT,
 		[DMAR_DSM_FUNC_ATSR] = ACPI_DMAR_TYPE_ROOT_ATS,
 		[DMAR_DSM_FUNC_RHSA] = ACPI_DMAR_TYPE_HARDWARE_AFFINITY,
+		[DMAR_DSM_FUNC_SATC] = ACPI_DMAR_TYPE_SATC,
 	};
 
 	if (!dmar_detect_dsm(handle, func))
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 761c1b251c1e..384cc546632a 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -316,8 +316,18 @@ struct dmar_atsr_unit {
 	u8 include_all:1;		/* include all ports */
 };
 
+struct dmar_satc_unit {
+	struct list_head list;		/* list of SATC units */
+	struct acpi_dmar_header *hdr;	/* ACPI header */
+	struct dmar_dev_scope *devices;	/* target devices */
+	struct intel_iommu *iommu;	/* the corresponding iommu */
+	int devices_cnt;		/* target device count */
+	u8 atc_required:1;		/* ATS is required */
+};
+
 static LIST_HEAD(dmar_atsr_units);
 static LIST_HEAD(dmar_rmrr_units);
+static LIST_HEAD(dmar_satc_units);
 
 #define for_each_rmrr_units(rmrr) \
 	list_for_each_entry(rmrr, &dmar_rmrr_units, list)
@@ -3716,6 +3726,57 @@ int dmar_check_one_atsr(struct acpi_dmar_header *hdr, void *arg)
 	return 0;
 }
 
+static struct dmar_satc_unit *dmar_find_satc(struct acpi_dmar_satc *satc)
+{
+	struct dmar_satc_unit *satcu;
+	struct acpi_dmar_satc *tmp;
+
+	list_for_each_entry_rcu(satcu, &dmar_satc_units, list,
+				dmar_rcu_check()) {
+		tmp = (struct acpi_dmar_satc *)satcu->hdr;
+		if (satc->segment != tmp->segment)
+			continue;
+		if (satc->header.length != tmp->header.length)
+			continue;
+		if (memcmp(satc, tmp, satc->header.length) == 0)
+			return satcu;
+	}
+
+	return NULL;
+}
+
+int dmar_parse_one_satc(struct acpi_dmar_header *hdr, void *arg)
+{
+	struct acpi_dmar_satc *satc;
+	struct dmar_satc_unit *satcu;
+
+	if (system_state >= SYSTEM_RUNNING && !intel_iommu_enabled)
+		return 0;
+
+	satc = container_of(hdr, struct acpi_dmar_satc, header);
+	satcu = dmar_find_satc(satc);
+	if (satcu)
+		return 0;
+
+	satcu = kzalloc(sizeof(*satcu) + hdr->length, GFP_KERNEL);
+	if (!satcu)
+		return -ENOMEM;
+
+	satcu->hdr = (void *)(satcu + 1);
+	memcpy(satcu->hdr, hdr, hdr->length);
+	satcu->atc_required = satc->flags & 0x1;
+	satcu->devices = dmar_alloc_dev_scope((void *)(satc + 1),
+					      (void *)satc + satc->header.length,
+					      &satcu->devices_cnt);
+	if (satcu->devices_cnt && !satcu->devices) {
+		kfree(satcu);
+		return -ENOMEM;
+	}
+	list_add_rcu(&satcu->list, &dmar_satc_units);
+
+	return 0;
+}
+
 static int intel_iommu_add(struct dmar_drhd_unit *dmaru)
 {
 	int sp, ret;
@@ -3823,6 +3884,7 @@ static void intel_iommu_free_dmars(void)
 {
 	struct dmar_rmrr_unit *rmrru, *rmrr_n;
 	struct dmar_atsr_unit *atsru, *atsr_n;
+	struct dmar_satc_unit *satcu, *satc_n;
 
 	list_for_each_entry_safe(rmrru, rmrr_n, &dmar_rmrr_units, list) {
 		list_del(&rmrru->list);
@@ -3834,6 +3896,11 @@ static void intel_iommu_free_dmars(void)
 		list_del(&atsru->list);
 		intel_iommu_free_atsr(atsru);
 	}
+	list_for_each_entry_safe(satcu, satc_n, &dmar_satc_units, list) {
+		list_del(&satcu->list);
+		dmar_free_dev_scope(&satcu->devices, &satcu->devices_cnt);
+		kfree(satcu);
+	}
 }
 
 int dmar_find_matched_atsr_unit(struct pci_dev *dev)
@@ -3885,8 +3952,10 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 	int ret;
 	struct dmar_rmrr_unit *rmrru;
 	struct dmar_atsr_unit *atsru;
+	struct dmar_satc_unit *satcu;
 	struct acpi_dmar_atsr *atsr;
 	struct acpi_dmar_reserved_memory *rmrr;
+	struct acpi_dmar_satc *satc;
 
 	if (!intel_iommu_enabled && system_state >= SYSTEM_RUNNING)
 		return 0;
@@ -3927,6 +3996,23 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 				break;
 		}
 	}
+	list_for_each_entry(satcu, &dmar_satc_units, list) {
+		satc = container_of(satcu->hdr, struct acpi_dmar_satc, header);
+		if (info->event == BUS_NOTIFY_ADD_DEVICE) {
+			ret = dmar_insert_dev_scope(info, (void *)(satc + 1),
+					(void *)satc + satc->header.length,
+					satc->segment, satcu->devices,
+					satcu->devices_cnt);
+			if (ret > 0)
+				break;
+			else if (ret < 0)
+				return ret;
+		} else if (info->event == BUS_NOTIFY_REMOVED_DEVICE) {
+			if (dmar_remove_dev_scope(info, satc->segment,
+					satcu->devices, satcu->devices_cnt))
+				break;
+		}
+	}
 
 	return 0;
 }
@@ -4270,6 +4356,9 @@ int __init intel_iommu_init(void)
 	if (list_empty(&dmar_atsr_units))
 		pr_info("No ATSR found\n");
 
+	if (list_empty(&dmar_satc_units))
+		pr_info("No SATC found\n");
+
 	if (dmar_map_gfx)
 		intel_iommu_gfx_mapped = 1;