x64, x2apic/intr-remap: code re-structuring, to be used by both DMA and Interrupt remapping

Allocate the iommu during the parse of DMA remapping hardware
definition structures. And also, introduce routines for device
scope initialization which will be explicitly called during
dma-remapping initialization.

These will be used for enabling interrupt remapping separately from the
existing DMA-remapping enabling sequence.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: akpm@linux-foundation.org
Cc: arjan@linux.intel.com
Cc: andi@firstfloor.org
Cc: ebiederm@xmission.com
Cc: jbarnes@virtuousgeek.org
Cc: steiner@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

drivers/pci/dmar.c

@@ -174,19 +174,37 @@ dmar_parse_one_drhd(struct acpi_dmar_header *header)
 	struct acpi_dmar_hardware_unit *drhd;
 	struct dmar_drhd_unit *dmaru;
 	int ret = 0;
-	static int include_all;
 
 	dmaru = kzalloc(sizeof(*dmaru), GFP_KERNEL);
 	if (!dmaru)
 		return -ENOMEM;
 
+	dmaru->hdr = header;
 	drhd = (struct acpi_dmar_hardware_unit *)header;
 	dmaru->reg_base_addr = drhd->address;
 	dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
 
+	ret = alloc_iommu(dmaru);
+	if (ret) {
+		kfree(dmaru);
+		return ret;
+	}
+	dmar_register_drhd_unit(dmaru);
+	return 0;
+}
+
+static int __init
+dmar_parse_dev(struct dmar_drhd_unit *dmaru)
+{
+	struct acpi_dmar_hardware_unit *drhd;
+	static int include_all;
+	int ret;
+
+	drhd = (struct acpi_dmar_hardware_unit *) dmaru->hdr;
+
 	if (!dmaru->include_all)
 		ret = dmar_parse_dev_scope((void *)(drhd + 1),
-				((void *)drhd) + header->length,
+				((void *)drhd) + drhd->header.length,
 				&dmaru->devices_cnt, &dmaru->devices,
 				drhd->segment);
 	else {
@@ -199,10 +217,10 @@ dmar_parse_one_drhd(struct acpi_dmar_header *header)
 		include_all = 1;
 	}
 
-	if (ret || (dmaru->devices_cnt == 0 && !dmaru->include_all))
+	if (ret || (dmaru->devices_cnt == 0 && !dmaru->include_all)) {
+		list_del(&dmaru->list);
 		kfree(dmaru);
-	else
-		dmar_register_drhd_unit(dmaru);
+	}
 	return ret;
 }
 
@@ -211,23 +229,35 @@ dmar_parse_one_rmrr(struct acpi_dmar_header *header)
 {
 	struct acpi_dmar_reserved_memory *rmrr;
 	struct dmar_rmrr_unit *rmrru;
-	int ret = 0;
 
 	rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL);
 	if (!rmrru)
 		return -ENOMEM;
 
+	rmrru->hdr = header;
 	rmrr = (struct acpi_dmar_reserved_memory *)header;
 	rmrru->base_address = rmrr->base_address;
 	rmrru->end_address = rmrr->end_address;
+
+	dmar_register_rmrr_unit(rmrru);
+	return 0;
+}
+
+static int __init
+rmrr_parse_dev(struct dmar_rmrr_unit *rmrru)
+{
+	struct acpi_dmar_reserved_memory *rmrr;
+	int ret;
+
+	rmrr = (struct acpi_dmar_reserved_memory *) rmrru->hdr;
 	ret = dmar_parse_dev_scope((void *)(rmrr + 1),
-		((void *)rmrr) + header->length,
+		((void *)rmrr) + rmrr->header.length,
 		&rmrru->devices_cnt, &rmrru->devices, rmrr->segment);
 
-	if (ret || (rmrru->devices_cnt == 0))
+	if (ret || (rmrru->devices_cnt == 0)) {
+		list_del(&rmrru->list);
 		kfree(rmrru);
-	else
-		dmar_register_rmrr_unit(rmrru);
+	}
 	return ret;
 }
 
@@ -333,15 +363,42 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev)
 	return NULL;
 }
 
+int __init dmar_dev_scope_init(void)
+{
+	struct dmar_drhd_unit *drhd;
+	struct dmar_rmrr_unit *rmrr;
+	int ret = -ENODEV;
+
+	for_each_drhd_unit(drhd) {
+		ret = dmar_parse_dev(drhd);
+		if (ret)
+			return ret;
+	}
+
+	for_each_rmrr_units(rmrr) {
+		ret = rmrr_parse_dev(rmrr);
+		if (ret)
+			return ret;
+	}
+
+	return ret;
+}
+
 
 int __init dmar_table_init(void)
 {
-
+	static int dmar_table_initialized;
 	int ret;
 
+	if (dmar_table_initialized)
+		return 0;
+
+	dmar_table_initialized = 1;
+
 	ret = parse_dmar_table();
 	if (ret) {
-		printk(KERN_INFO PREFIX "parse DMAR table failure.\n");
+		if (ret != -ENODEV)
+			printk(KERN_INFO PREFIX "parse DMAR table failure.\n");
 		return ret;
 	}
 
@@ -377,7 +434,7 @@ int __init early_dmar_detect(void)
 	return (ACPI_SUCCESS(status) ? 1 : 0);
 }
 
-struct intel_iommu *alloc_iommu(struct dmar_drhd_unit *drhd)
+int alloc_iommu(struct dmar_drhd_unit *drhd)
 {
 	struct intel_iommu *iommu;
 	int map_size;
@@ -386,7 +443,7 @@ struct intel_iommu *alloc_iommu(struct dmar_drhd_unit *drhd)
 
 	iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
 	if (!iommu)
-		return NULL;
+		return -ENOMEM;
 
 	iommu->seq_id = iommu_allocated++;
 
@@ -419,10 +476,10 @@ struct intel_iommu *alloc_iommu(struct dmar_drhd_unit *drhd)
 	spin_lock_init(&iommu->register_lock);
 
 	drhd->iommu = iommu;
-	return iommu;
+	return 0;
 error:
 	kfree(iommu);
-	return NULL;
+	return -1;
 }
 
 void free_iommu(struct intel_iommu *iommu)

drivers/pci/intel-iommu.c

@@ -1665,11 +1665,8 @@ int __init init_dmars(void)
 	for_each_drhd_unit(drhd) {
 		if (drhd->ignored)
 			continue;
-		iommu = alloc_iommu(drhd);
-		if (!iommu) {
-			ret = -ENOMEM;
-			goto error;
-		}
+
+		iommu = drhd->iommu;
 
 		ret = iommu_init_domains(iommu);
 		if (ret)
@@ -2324,6 +2321,9 @@ int __init intel_iommu_init(void)
 	if (dmar_table_init())
 		return 	-ENODEV;
 
+	if (dmar_dev_scope_init())
+		return 	-ENODEV;
+
 	iommu_init_mempool();
 	dmar_init_reserved_ranges();
 

drivers/pci/intel-iommu.h

@@ -199,7 +199,7 @@ struct intel_iommu {
 
 extern struct dmar_drhd_unit * dmar_find_matched_drhd_unit(struct pci_dev *dev);
 
-extern struct intel_iommu *alloc_iommu(struct dmar_drhd_unit *drhd);
+extern int alloc_iommu(struct dmar_drhd_unit *drhd);
 extern void free_iommu(struct intel_iommu *iommu);
 
 #endif

include/linux/dmar.h

@@ -46,12 +46,14 @@ extern int intel_iommu_init(void);
 
 extern int dmar_table_init(void);
 extern int early_dmar_detect(void);
+extern int dmar_dev_scope_init(void);
 
 extern struct list_head dmar_drhd_units;
 extern struct list_head dmar_rmrr_units;
 
 struct dmar_drhd_unit {
 	struct list_head list;		/* list of drhd units	*/
+	struct  acpi_dmar_header *hdr;	/* ACPI header		*/
 	u64	reg_base_addr;		/* register base address*/
 	struct	pci_dev **devices; 	/* target device array	*/
 	int	devices_cnt;		/* target device count	*/
@@ -62,6 +64,7 @@ struct dmar_drhd_unit {
 
 struct dmar_rmrr_unit {
 	struct list_head list;		/* list of rmrr units	*/
+	struct acpi_dmar_header *hdr;	/* ACPI header		*/
 	u64	base_address;		/* reserved base address*/
 	u64	end_address;		/* reserved end address */
 	struct pci_dev **devices;	/* target devices */
@@ -72,6 +75,8 @@ struct dmar_rmrr_unit {
 	list_for_each_entry(drhd, &dmar_drhd_units, list)
 #define for_each_rmrr_units(rmrr) \
 	list_for_each_entry(rmrr, &dmar_rmrr_units, list)
+
+extern int alloc_iommu(struct dmar_drhd_unit *);
 #else
 static inline void detect_intel_iommu(void)
 {
@@ -81,6 +86,9 @@ static inline int intel_iommu_init(void)
 {
 	return -ENODEV;
 }
-
+static inline int dmar_table_init(void)
+{
+	return -ENODEV;
+}
 #endif /* !CONFIG_DMAR */
 #endif /* __DMAR_H__ */