[RFC PATCH 14/14] IOMMU: Add intel iommu irq-remapping and dmar hotplug support

Yinghai Lu
2012-04-03T02:20:12Z

Will use acpi_pci_driver to parse and init them between pci root bus scanning
and start.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
drivers/iommu/dmar.c | 218 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 218 insertions(+), 0 deletions(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index f96b8ce..918a063 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -36,6 +36,7 @@
#include <linux/tboot.h>
#include <linux/dmi.h>
#include <linux/slab.h>
+#include <acpi/acpi.h>
#include <asm/irq_remapping.h>
#include <asm/iommu_table.h>

@@ -1480,3 +1481,220 @@ int __init dmar_ir_support(void)
return dmar->flags & 0x1;
}
IOMMU_INIT_POST(detect_intel_iommu);
+
+#ifdef CONFIG_HOTPLUG
+static u8 dmar_uuid_str[] = "D8C1A3A6-BE9B-4C9B-91BF-C3CB81FC5DAF";
+
+static int acpi_dmar_dsm_support(acpi_handle handle)
+{
+ int support = 0;
+ struct acpi_dsm_context context = {
+ .uuid_str = dmar_uuid_str,
+ .rev = 1,
+ .func_idx = 0,
+ };
+
+ if (ACPI_SUCCESS(acpi_run_dsm(handle, &context))) {
+ u32 *ret = context.ret.pointer;
+ support = ret[0];
+ kfree(context.ret.pointer);
+ }
+
+ if (support & 1)
+ return support & 0x0e;
+
+ return 0;
+}
+
+static void *acpi_dmar_dsm_run(acpi_handle handle, int idx)
+{
+ struct acpi_dsm_context context = {
+ .uuid_str = dmar_uuid_str,
+ .rev = 1,
+ .func_idx = idx,
+ };
+
+ if (ACPI_SUCCESS(acpi_run_dsm(handle, &context)))
+ return context.ret.pointer;
+
+ return NULL;
+}
+
+static void handle_iommu_add(acpi_handle handle, void **d, void **a)
+{
+ int support;
+ struct acpi_dmar_header *header;
+ struct dmar_drhd_unit *dmaru = NULL;
+ struct dmar_atsr_unit *atsru = NULL;
+
+ *d = NULL;
+ *a = NULL;
+
+ support = acpi_dmar_dsm_support(handle);
+
+ if (!support)
+ return;
+
+ /* DRHD */
+ if (support & (1<<1)) {
+ header = acpi_dmar_dsm_run(handle, 1);
+ dmar_table_print_dmar_entry(header);
+ __dmar_parse_one_drhd(header, &dmaru);
+ }
+
+ if (!dmaru)
+ return;
+
+ /* ATSR */
+ if (support & (1<<2)) {
+ header = acpi_dmar_dsm_run(handle, 2);
+ dmar_table_print_dmar_entry(header);
+ __dmar_parse_one_atsr(header, &atsru);
+ }
+
+ /* RHSA */
+ if (support & (1<<3)) {
+ header = acpi_dmar_dsm_run(handle, 3);
+ dmar_table_print_dmar_entry(header);
+ dmar_parse_one_rhsa(header);
+ kfree(header);
+ }
+
+ /*
+ * only need to init intr_remap and dmar for hot-add ones
+ * after enable_IR() or pci_iommu_init
+ */
+ /*
+ * TODO: handle parsing failure for pre-installed hotplug one
+ * Could make every parse_one duplicate the entry table?
+ */
+ if (irq_remapping_enabled == 1)
+ intel_enable_irq_remapping_one(dmaru);
+ if (irq_remapping_enabled == 1 || intel_iommu_enabled == 1)
+ dmar_parse_dev(dmaru);
+ if (intel_iommu_enabled == 1) {
+ init_dmar_one(dmaru);
+ if (atsru) {
+ header = atsru->hdr;
+ if (atsr_parse_dev(atsru)) {
+ kfree(header);
+ atsru = NULL;
+ }
+ *a = atsru;
+ }
+ }
+ *d = dmaru;
+}
+
+static void handle_iommu_remove(void *drhd, void *atsr)
+{
+ struct dmar_drhd_unit *dmaru = drhd;
+ struct dmar_atsr_unit *atsru = atsr;
+
+ if (!dmaru)
+ return;
+
+ if (irq_remapping_enabled == 1)
+ disable_irq_remapping_one(dmaru);
+ if (intel_iommu_enabled == 1) {
+ free_dmar_iommu(dmaru->iommu);
+ if (atsru) {
+ kfree(atsru->devices);
+ remove_atsru_from_saved_dev_atsru_list(atsru);
+ }
+ }
+ if (irq_remapping_enabled == 1 || intel_iommu_enabled == 1) {
+ kfree(dmaru->devices);
+ remove_dmaru_from_saved_dev_drhd_list(dmaru);
+ }
+ if (atsru) {
+ kfree(atsru->hdr);
+ list_del(&atsru->list);
+ kfree(atsru);
+ }
+ free_iommu(dmaru->iommu);
+ kfree(dmaru->hdr);
+ list_del(&dmaru->list);
+ kfree(dmaru);
+}
+
+struct acpi_pci_iommu {
+ acpi_handle root_handle;
+ void *dmaru;
+ void *atsru;
+ struct list_head list;
+};
+
+static LIST_HEAD(iommu_list);
+static DEFINE_MUTEX(iommu_list_lock);
+
+static acpi_status register_iommu(acpi_handle handle, u32 lvl,
+ void *context, void **rv)
+{
+ acpi_handle root_handle = context;
+ void *dmaru, *atsru;
+ struct acpi_pci_iommu *iommu;
+
+ handle_iommu_add(handle, &dmaru, &atsru);
+ if (!dmaru)
+ return AE_OK;
+
+ iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
+ if (!iommu) {
+ printk(KERN_ERR "%s: cannot allocate memory\n", __func__);
+ handle_iommu_remove(dmaru, atsru);
+ return AE_OK;
+ }
+ iommu->root_handle = root_handle;
+ iommu->dmaru = dmaru;
+ iommu->atsru = atsru;
+
+ mutex_lock(&iommu_list_lock);
+ list_add(&iommu->list, &iommu_list);
+ mutex_unlock(&iommu_list_lock);
+
+ return AE_OK;
+}
+
+static int acpi_pci_iommu_add(acpi_handle handle)
+{
+ acpi_status status;
+
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
+ register_iommu, NULL, handle, NULL);
+ if (ACPI_FAILURE(status))
+ printk(KERN_ERR "%s: register_iommu failure - %d", __func__,
+ status);
+
+ return status;
+}
+
+static void acpi_pci_iommu_remove(acpi_handle handle)
+{
+ struct acpi_pci_iommu *iommu, *tmp;
+
+ mutex_lock(&iommu_list_lock);
+ list_for_each_entry_safe(iommu, tmp, &iommu_list, list) {
+ if (handle != iommu->root_handle)
+ continue;
+ list_del(&iommu->list);
+ handle_iommu_remove(iommu->dmaru, iommu->atsru);
+ kfree(iommu);
+ }
+ mutex_unlock(&iommu_list_lock);
+}
+
+static struct acpi_pci_driver acpi_pci_iommu_driver = {
+ .add = acpi_pci_iommu_add,
+ .remove = acpi_pci_iommu_remove,
+};
+
+static int __init acpi_pci_iommu_init(void)
+{
+ acpi_pci_register_driver(&acpi_pci_iommu_driver);
+
+ return 0;
+}
+
+subsys_initcall(acpi_pci_iommu_init);
+#endif
--
1.7.7