Intel IOMMU Suspend/Resume Support - Interrupt Remapping
This patch enables suspend/resume for interrupt remapping. During suspend,
interrupt remapping is disabled. When resume, interrupt remapping is enabled
again.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 85eb8e1..098ec84 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1304,6 +1304,7 @@
#ifdef CONFIG_INTR_REMAP
int ret;
unsigned long flags;
+ struct IO_APIC_route_entry **ioapic_entries = NULL;
if (!cpu_has_x2apic)
return;
@@ -1334,17 +1335,23 @@
return;
}
- ret = save_IO_APIC_setup();
+ ioapic_entries = alloc_ioapic_entries();
+ if (!ioapic_entries) {
+ pr_info("Allocate ioapic_entries failed: %d\n", ret);
+ goto end;
+ }
+
+ ret = save_IO_APIC_setup(ioapic_entries);
if (ret) {
pr_info("Saving IO-APIC state failed: %d\n", ret);
goto end;
}
local_irq_save(flags);
- mask_IO_APIC_setup();
+ mask_IO_APIC_setup(ioapic_entries);
mask_8259A();
- ret = enable_intr_remapping(1);
+ ret = enable_intr_remapping(EIM_32BIT_APIC_ID);
if (ret && x2apic_preenabled) {
local_irq_restore(flags);
@@ -1364,9 +1371,9 @@
/*
* IR enabling failed
*/
- restore_IO_APIC_setup();
+ restore_IO_APIC_setup(ioapic_entries);
else
- reinit_intr_remapped_IO_APIC(x2apic_preenabled);
+ reinit_intr_remapped_IO_APIC(x2apic_preenabled, ioapic_entries);
unmask_8259A();
local_irq_restore(flags);
@@ -1379,6 +1386,8 @@
pr_info("Enabled Interrupt-remapping\n");
} else
pr_err("Failed to enable Interrupt-remapping and x2apic\n");
+ if (ioapic_entries)
+ free_ioapic_entries(ioapic_entries);
#else
if (!cpu_has_x2apic)
return;
@@ -1954,6 +1963,10 @@
local_irq_save(flags);
disable_local_APIC();
+#ifdef CONFIG_INTR_REMAP
+ if (intr_remapping_enabled)
+ disable_intr_remapping();
+#endif
local_irq_restore(flags);
return 0;
}
@@ -1964,15 +1977,41 @@
unsigned long flags;
int maxlvt;
+#ifdef CONFIG_INTR_REMAP
+ int ret;
+ struct IO_APIC_route_entry **ioapic_entries = NULL;
+
if (!apic_pm_state.active)
return 0;
- maxlvt = lapic_get_maxlvt();
+ local_irq_save(flags);
+ if (x2apic) {
+ ioapic_entries = alloc_ioapic_entries();
+ if (!ioapic_entries) {
+ WARN(1, "Alloc ioapic_entries in lapic resume failed.");
+ return -ENOMEM;
+ }
+
+ ret = save_IO_APIC_setup(ioapic_entries);
+ if (ret) {
+ WARN(1, "Saving IO-APIC state failed: %d\n", ret);
+ free_ioapic_entries(ioapic_entries);
+ return ret;
+ }
+
+ mask_IO_APIC_setup(ioapic_entries);
+ mask_8259A();
+ enable_x2apic();
+ }
+#else
+ if (!apic_pm_state.active)
+ return 0;
local_irq_save(flags);
-
if (x2apic)
enable_x2apic();
+#endif
+
else {
/*
* Make sure the APICBASE points to the right address
@@ -1986,6 +2025,7 @@
wrmsr(MSR_IA32_APICBASE, l, h);
}
+ maxlvt = lapic_get_maxlvt();
apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
apic_write(APIC_ID, apic_pm_state.apic_id);
apic_write(APIC_DFR, apic_pm_state.apic_dfr);
@@ -2009,8 +2049,20 @@
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
+#ifdef CONFIG_INTR_REMAP
+ if (intr_remapping_enabled)
+ reenable_intr_remapping(EIM_32BIT_APIC_ID);
+
+ if (x2apic) {
+ unmask_8259A();
+ restore_IO_APIC_setup(ioapic_entries);
+ free_ioapic_entries(ioapic_entries);
+ }
+#endif
+
local_irq_restore(flags);
+
return 0;
}
@@ -2048,7 +2100,9 @@
error = sysdev_register(&device_lapic);
return error;
}
-device_initcall(init_lapic_sysfs);
+
+/* local apic needs to resume before other devices access its registers. */
+core_initcall(init_lapic_sysfs);
#else /* CONFIG_PM */
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 1bb5c6c..0ad3fe7 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -851,63 +851,74 @@
#endif /* CONFIG_X86_32 */
#ifdef CONFIG_INTR_REMAP
-/* I/O APIC RTE contents at the OS boot up */
-static struct IO_APIC_route_entry *early_ioapic_entries[MAX_IO_APICS];
+struct IO_APIC_route_entry **alloc_ioapic_entries(void)
+{
+ int apic;
+ struct IO_APIC_route_entry **ioapic_entries;
+
+ ioapic_entries = kzalloc(sizeof(*ioapic_entries) * nr_ioapics,
+ GFP_ATOMIC);
+ if (!ioapic_entries)
+ return 0;
+
+ for (apic = 0; apic < nr_ioapics; apic++) {
+ ioapic_entries[apic] =
+ kzalloc(sizeof(struct IO_APIC_route_entry) *
+ nr_ioapic_registers[apic], GFP_ATOMIC);
+ if (!ioapic_entries[apic])
+ goto nomem;
+ }
+
+ return ioapic_entries;
+
+nomem:
+ while (--apic >= 0)
+ kfree(ioapic_entries[apic]);
+ kfree(ioapic_entries);
+
+ return 0;
+}
/*
* Saves all the IO-APIC RTE's
*/
-int save_IO_APIC_setup(void)
+int save_IO_APIC_setup(struct IO_APIC_route_entry **ioapic_entries)
{
- union IO_APIC_reg_01 reg_01;
- unsigned long flags;
int apic, pin;
- /*
- * The number of IO-APIC IRQ registers (== #pins):
- */
- for (apic = 0; apic < nr_ioapics; apic++) {
- spin_lock_irqsave(&ioapic_lock, flags);
- reg_01.raw = io_apic_read(apic, 1);
- spin_unlock_irqrestore(&ioapic_lock, flags);
- nr_ioapic_registers[apic] = reg_01.bits.entries+1;
- }
+ if (!ioapic_entries)
+ return -ENOMEM;
for (apic = 0; apic < nr_ioapics; apic++) {
- early_ioapic_entries[apic] =
- kzalloc(sizeof(struct IO_APIC_route_entry) *
- nr_ioapic_registers[apic], GFP_KERNEL);
- if (!early_ioapic_entries[apic])
- goto nomem;
- }
+ if (!ioapic_entries[apic])
+ return -ENOMEM;
- for (apic = 0; apic < nr_ioapics; apic++)
for (pin = 0; pin < nr_ioapic_registers[apic]; pin++)
- early_ioapic_entries[apic][pin] =
+ ioapic_entries[apic][pin] =
ioapic_read_entry(apic, pin);
+ }
return 0;
-
-nomem:
- while (apic >= 0)
- kfree(early_ioapic_entries[apic--]);
- memset(early_ioapic_entries, 0,
- ARRAY_SIZE(early_ioapic_entries));
-
- return -ENOMEM;
}
-void mask_IO_APIC_setup(void)
+/*
+ * Mask all IO APIC entries.
+ */
+void mask_IO_APIC_setup(struct IO_APIC_route_entry **ioapic_entries)
{
int apic, pin;
+ if (!ioapic_entries)
+ return;
+
for (apic = 0; apic < nr_ioapics; apic++) {
- if (!early_ioapic_entries[apic])
+ if (!ioapic_entries[apic])
break;
+
for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
struct IO_APIC_route_entry entry;
- entry = early_ioapic_entries[apic][pin];
+ entry = ioapic_entries[apic][pin];
if (!entry.mask) {
entry.mask = 1;
ioapic_write_entry(apic, pin, entry);
@@ -916,22 +927,30 @@
}
}
-void restore_IO_APIC_setup(void)
+/*
+ * Restore IO APIC entries which was saved in ioapic_entries.
+ */
+int restore_IO_APIC_setup(struct IO_APIC_route_entry **ioapic_entries)
{
int apic, pin;
+ if (!ioapic_entries)
+ return -ENOMEM;
+
for (apic = 0; apic < nr_ioapics; apic++) {
- if (!early_ioapic_entries[apic])
- break;
+ if (!ioapic_entries[apic])
+ return -ENOMEM;
+
for (pin = 0; pin < nr_ioapic_registers[apic]; pin++)
ioapic_write_entry(apic, pin,
- early_ioapic_entries[apic][pin]);
- kfree(early_ioapic_entries[apic]);
- early_ioapic_entries[apic] = NULL;
+ ioapic_entries[apic][pin]);
}
+ return 0;
}
-void reinit_intr_remapped_IO_APIC(int intr_remapping)
+void reinit_intr_remapped_IO_APIC(int intr_remapping,
+ struct IO_APIC_route_entry **ioapic_entries)
+
{
/*
* for now plain restore of previous settings.
@@ -940,7 +959,17 @@
* table entries. for now, do a plain restore, and wait for
* the setup_IO_APIC_irqs() to do proper initialization.
*/
- restore_IO_APIC_setup();
+ restore_IO_APIC_setup(ioapic_entries);
+}
+
+void free_ioapic_entries(struct IO_APIC_route_entry **ioapic_entries)
+{
+ int apic;
+
+ for (apic = 0; apic < nr_ioapics; apic++)
+ kfree(ioapic_entries[apic]);
+
+ kfree(ioapic_entries);
}
#endif