[PATCH v2 01/10] IOMMU: Update dmar units devices list during hotplug
From: Yinghai Lu
Date: Thu Jan 02 2014 - 19:08:27 EST
When do pci remove/rescan on system that have more iommus, got
[ 894.089745] Set context mapping for c4:00.0
[ 894.110890] mpt2sas3: Allocated physical memory: size(4293 kB)
[ 894.112556] mpt2sas3: Current Controller Queue Depth(1883), Max Controller Queue Depth(2144)
[ 894.127278] mpt2sas3: Scatter Gather Elements per IO(128)
[ 894.361295] DRHD: handling fault status reg 2
[ 894.364053] DMAR:[DMA Read] Request device [c4:00.0] fault addr fffbe000
[ 894.364056] DMAR:[fault reason 02] Present bit in context entry is cl
It turns out when remove/rescan, pci dev will be freed and will get another
new dev. But drhd units still keep old one... so dmar_find_matched_drhd_unit
will return wrong drhd and iommu for the device that is not on first iommu.
So need to update devices in drhd_units during pci remove/rescan.
Could save domain/bus/device/function aside in the list and according that
info restore new dev to drhd_units later.
Then dmar_find_matched_drdh_unit and device_to_iommu could return right drhd
and iommu.
Add remove_dev_from_drhd/restore_dev_to_drhd functions to do the real work.
call them in device ADD_DEVICE and UNBOUND_DRIVER
Need to do the samething to atsr. (expose dmar_atsr_units and add
atsru->segment)
After patch, will have right iommu for the new dev and will not get DMAR
error anymore.
-v2: add pci_dev_put/pci_dev_get to make refcount consistent.
-v3: fix one left over CONFIG_DMAR
-v4: pass pci_dev *dev in save_dev_dmaru()/get_dev_dmaru() according to Bjorn.
-v5: fix case only have intr-remap enabled.
-v6: skip handling of vf adding/removing.
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: Vinod Koul <vinod.koul@xxxxxxxxx>
Cc: Dan Williams <djbw@xxxxxx>
Cc: Donald Dutile <ddutile@xxxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
---
drivers/iommu/dmar.c | 138 ++++++++++++++++++++++++++++++++++++
drivers/iommu/intel-iommu.c | 32 +++++----
drivers/iommu/intel_irq_remapping.c | 33 ++++++++-
include/linux/dmar.h | 10 +++
4 files changed, 200 insertions(+), 13 deletions(-)
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index f4eaa50..a14867c 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -450,6 +450,144 @@ fail:
return ret;
}
+struct dev_dmaru {
+ struct list_head list;
+ void *dmaru;
+ int index;
+ int segment;
+ unsigned char bus;
+ unsigned int devfn;
+};
+
+static int save_dev_dmaru(struct pci_dev *dev, void *dmaru,
+ int index, struct list_head *lh)
+{
+ struct dev_dmaru *m;
+
+ m = kzalloc(sizeof(*m), GFP_KERNEL);
+ if (!m)
+ return -ENOMEM;
+
+ m->segment = pci_domain_nr(dev->bus);
+ m->bus = dev->bus->number;
+ m->devfn = dev->devfn;
+ m->dmaru = dmaru;
+ m->index = index;
+
+ list_add(&m->list, lh);
+
+ return 0;
+}
+static void *get_dev_dmaru(struct pci_dev *dev, int *index,
+ struct list_head *lh)
+{
+ int segment = pci_domain_nr(dev->bus);
+ unsigned char bus = dev->bus->number;
+ unsigned int devfn = dev->devfn;
+ struct dev_dmaru *m;
+ void *dmaru = NULL;
+
+ list_for_each_entry(m, lh, list) {
+ if (m->segment == segment &&
+ m->bus == bus && m->devfn == devfn) {
+ *index = m->index;
+ dmaru = m->dmaru;
+ list_del(&m->list);
+ kfree(m);
+ break;
+ }
+ }
+
+ return dmaru;
+}
+
+static LIST_HEAD(saved_dev_drhd_list);
+void remove_dev_from_drhd(struct pci_dev *dev)
+{
+ struct dmar_drhd_unit *drhd = NULL;
+ int segment = pci_domain_nr(dev->bus);
+ int i;
+
+ if (dev->is_virtfn)
+ return;
+
+ for_each_drhd_unit(drhd) {
+ if (drhd->ignored)
+ continue;
+ if (segment != drhd->segment)
+ continue;
+
+ for (i = 0; i < drhd->devices_cnt; i++) {
+ if (drhd->devices[i] == dev) {
+ /* save it at first if it is in drhd */
+ save_dev_dmaru(dev, drhd, i,
+ &saved_dev_drhd_list);
+ /* always remove it */
+ pci_dev_put(dev);
+ drhd->devices[i] = NULL;
+ return;
+ }
+ }
+ }
+}
+void restore_dev_to_drhd(struct pci_dev *dev)
+{
+ struct dmar_drhd_unit *drhd = NULL;
+ int i;
+
+ if (dev->is_virtfn)
+ return;
+
+ /* find the stored drhd */
+ drhd = get_dev_dmaru(dev, &i, &saved_dev_drhd_list);
+ /* restore that into drhd */
+ if (drhd)
+ drhd->devices[i] = pci_dev_get(dev);
+}
+
+#ifdef CONFIG_INTEL_IOMMU
+static LIST_HEAD(saved_dev_atsr_list);
+void remove_dev_from_atsr(struct pci_dev *dev)
+{
+ struct dmar_atsr_unit *atsr = NULL;
+ int segment = pci_domain_nr(dev->bus);
+ int i;
+
+ if (dev->is_virtfn)
+ return;
+
+ for_each_atsr_unit(atsr) {
+ if (segment != atsr->segment)
+ continue;
+
+ for (i = 0; i < atsr->devices_cnt; i++) {
+ if (atsr->devices[i] == dev) {
+ /* save it at first if it is in drhd */
+ save_dev_dmaru(dev, atsr, i,
+ &saved_dev_atsr_list);
+ /* always remove it */
+ pci_dev_put(dev);
+ atsr->devices[i] = NULL;
+ return;
+ }
+ }
+ }
+}
+void restore_dev_to_atsr(struct pci_dev *dev)
+{
+ struct dmar_atsr_unit *atsr = NULL;
+ int i;
+
+ if (dev->is_virtfn)
+ return;
+
+ /* find the stored atsr */
+ atsr = get_dev_dmaru(dev, &i, &saved_dev_atsr_list);
+ /* restore that into atsr */
+ if (atsr)
+ atsr->devices[i] = pci_dev_get(dev);
+}
+#endif /* CONFIG_INTEL_IOMMU */
int __init dmar_table_init(void)
{
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 43b9bfe..a3eb689 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3528,7 +3528,7 @@ rmrr_parse_dev(struct dmar_rmrr_unit *rmrru)
return ret;
}
-static LIST_HEAD(dmar_atsr_units);
+LIST_HEAD(dmar_atsr_units);
int __init dmar_parse_one_atsr(struct acpi_dmar_header *hdr)
{
@@ -3542,6 +3542,7 @@ int __init dmar_parse_one_atsr(struct acpi_dmar_header *hdr)
atsru->hdr = hdr;
atsru->include_all = atsr->flags & 0x1;
+ atsru->segment = atsr->segment;
list_add(&atsru->list, &dmar_atsr_units);
@@ -3573,16 +3574,13 @@ int dmar_find_matched_atsr_unit(struct pci_dev *dev)
{
int i;
struct pci_bus *bus;
- struct acpi_dmar_atsr *atsr;
struct dmar_atsr_unit *atsru;
dev = pci_physfn(dev);
- list_for_each_entry(atsru, &dmar_atsr_units, list) {
- atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
- if (atsr->segment == pci_domain_nr(dev->bus))
+ list_for_each_entry(atsru, &dmar_atsr_units, list)
+ if (atsru->segment == pci_domain_nr(dev->bus))
goto found;
- }
return 0;
@@ -3642,20 +3640,30 @@ static int device_notifier(struct notifier_block *nb,
struct pci_dev *pdev = to_pci_dev(dev);
struct dmar_domain *domain;
- if (iommu_no_mapping(dev))
- return 0;
+ switch (action) {
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ if (iommu_no_mapping(dev) || iommu_pass_through)
+ break;
- domain = find_domain(pdev);
- if (!domain)
- return 0;
+ domain = find_domain(pdev);
+ if (!domain)
+ break;
- if (action == BUS_NOTIFY_UNBOUND_DRIVER && !iommu_pass_through) {
domain_remove_one_dev_info(domain, pdev);
if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) &&
!(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) &&
list_empty(&domain->devices))
domain_exit(domain);
+ break;
+ case BUS_NOTIFY_DEL_DEVICE:
+ remove_dev_from_drhd(pdev);
+ remove_dev_from_atsr(pdev);
+ break;
+ case BUS_NOTIFY_ADD_DEVICE:
+ restore_dev_to_drhd(pdev);
+ restore_dev_to_atsr(pdev);
+ break;
}
return 0;
diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 07ab6e8..8471f40 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -807,12 +807,43 @@ int __init parse_ioapics_under_ir(void)
return 1;
}
+static int device_notifier(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+ struct pci_dev *pdev = to_pci_dev(dev);
+
+ switch (action) {
+ case BUS_NOTIFY_DEL_DEVICE:
+ remove_dev_from_drhd(pdev);
+ break;
+ case BUS_NOTIFY_ADD_DEVICE:
+ restore_dev_to_drhd(pdev);
+ break;
+ }
+
+ return 0;
+}
+
+static struct notifier_block device_nb = {
+ .notifier_call = device_notifier,
+};
+
int __init ir_dev_scope_init(void)
{
+ int ret;
+
if (!irq_remapping_enabled)
return 0;
- return dmar_dev_scope_init();
+ ret = dmar_dev_scope_init();
+ if (ret < 0)
+ return ret;
+
+ if (intel_iommu_enabled != 1)
+ bus_register_notifier(&pci_bus_type, &device_nb);
+
+ return ret;
}
rootfs_initcall(ir_dev_scope_init);
diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index b029d1a..0a3dd71 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -131,6 +131,11 @@ extern int dmar_set_interrupt(struct intel_iommu *iommu);
extern irqreturn_t dmar_fault(int irq, void *dev_id);
extern int arch_setup_dmar_msi(unsigned int irq);
+void remove_dev_from_drhd(struct pci_dev *dev);
+void restore_dev_to_drhd(struct pci_dev *dev);
+void remove_dev_from_atsr(struct pci_dev *dev);
+void restore_dev_to_atsr(struct pci_dev *dev);
+
#ifdef CONFIG_INTEL_IOMMU
extern int iommu_detected, no_iommu;
extern struct list_head dmar_rmrr_units;
@@ -146,14 +151,19 @@ struct dmar_rmrr_unit {
#define for_each_rmrr_units(rmrr) \
list_for_each_entry(rmrr, &dmar_rmrr_units, list)
+extern struct list_head dmar_atsr_units;
struct dmar_atsr_unit {
struct list_head list; /* list of ATSR units */
struct acpi_dmar_header *hdr; /* ACPI header */
struct pci_dev **devices; /* target devices */
int devices_cnt; /* target device count */
+ u16 segment; /* PCI domain */
u8 include_all:1; /* include all ports */
};
+#define for_each_atsr_unit(atsr) \
+ list_for_each_entry(atsr, &dmar_atsr_units, list)
+
int dmar_parse_rmrr_atsr_dev(void);
extern int dmar_parse_one_rmrr(struct acpi_dmar_header *header);
extern int dmar_parse_one_atsr(struct acpi_dmar_header *header);
--
1.8.4
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