iommu/amd: Introduce per PCI segment unity map list

Newer AMD systems can support multiple PCI segments. In order to support
multiple PCI segments IVMD table in IVRS structure is enhanced to
include pci segment id. Update ivmd_header structure to include "pci_seg".

Also introduce per PCI segment unity map list. It will replace global
amd_iommu_unity_map list.

Note that we have used "reserved" field in IVMD table to include "pci_seg
id" which was set to zero. It will take care of backward compatibility
(new kernel will work fine on older systems).

Co-developed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220706113825.25582-10-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 20 insertions, 10 deletions

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 2c8dbf2332bd..779505610164 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -141,7 +141,8 @@ struct ivmd_header {
 	u16 length;
 	u16 devid;
 	u16 aux;
-	u64 resv;
+	u16 pci_seg;
+	u8  resv[6];
 	u64 range_start;
 	u64 range_length;
 } __attribute__((packed));
@@ -161,8 +162,6 @@ static int amd_iommu_target_ivhd_type;
 
 u16 amd_iommu_last_bdf;			/* largest PCI device id we have
 					   to handle */
-LIST_HEAD(amd_iommu_unity_map);		/* a list of required unity mappings
-					   we find in ACPI */
 
 LIST_HEAD(amd_iommu_pci_seg_list);	/* list of all PCI segments */
 LIST_HEAD(amd_iommu_list);		/* list of all AMD IOMMUs in the
@@ -1564,6 +1563,7 @@ static struct amd_iommu_pci_seg *__init alloc_pci_segment(u16 id)
 
 	pci_seg->id = id;
 	init_llist_head(&pci_seg->dev_data_list);
+	INIT_LIST_HEAD(&pci_seg->unity_map);
 	list_add_tail(&pci_seg->list, &amd_iommu_pci_seg_list);
 
 	if (alloc_dev_table(pci_seg))
@@ -2401,10 +2401,13 @@ enable_faults:
 static void __init free_unity_maps(void)
 {
 	struct unity_map_entry *entry, *next;
+	struct amd_iommu_pci_seg *p, *pci_seg;
 
-	list_for_each_entry_safe(entry, next, &amd_iommu_unity_map, list) {
-		list_del(&entry->list);
-		kfree(entry);
+	for_each_pci_segment_safe(pci_seg, p) {
+		list_for_each_entry_safe(entry, next, &pci_seg->unity_map, list) {
+			list_del(&entry->list);
+			kfree(entry);
+		}
 	}
 }
 
@@ -2412,8 +2415,13 @@ static void __init free_unity_maps(void)
 static int __init init_unity_map_range(struct ivmd_header *m)
 {
 	struct unity_map_entry *e = NULL;
+	struct amd_iommu_pci_seg *pci_seg;
 	char *s;
 
+	pci_seg = get_pci_segment(m->pci_seg);
+	if (pci_seg == NULL)
+		return -ENOMEM;
+
 	e = kzalloc(sizeof(*e), GFP_KERNEL);
 	if (e == NULL)
 		return -ENOMEM;
@@ -2451,14 +2459,16 @@ static int __init init_unity_map_range(struct ivmd_header *m)
 	if (m->flags & IVMD_FLAG_EXCL_RANGE)
 		e->prot = (IVMD_FLAG_IW | IVMD_FLAG_IR) >> 1;
 
-	DUMP_printk("%s devid_start: %02x:%02x.%x devid_end: %02x:%02x.%x"
-		    " range_start: %016llx range_end: %016llx flags: %x\n", s,
+	DUMP_printk("%s devid_start: %04x:%02x:%02x.%x devid_end: "
+		    "%04x:%02x:%02x.%x range_start: %016llx range_end: %016llx"
+		    " flags: %x\n", s, m->pci_seg,
 		    PCI_BUS_NUM(e->devid_start), PCI_SLOT(e->devid_start),
-		    PCI_FUNC(e->devid_start), PCI_BUS_NUM(e->devid_end),
+		    PCI_FUNC(e->devid_start), m->pci_seg,
+		    PCI_BUS_NUM(e->devid_end),
 		    PCI_SLOT(e->devid_end), PCI_FUNC(e->devid_end),
 		    e->address_start, e->address_end, m->flags);
 
-	list_add_tail(&e->list, &amd_iommu_unity_map);
+	list_add_tail(&e->list, &pci_seg->unity_map);
 
 	return 0;
 }