[PATCH 34/50] ACPI, Record ACPI NVS regions

From: Len Brown
Date: Tue Jan 17 2012 - 07:24:05 EST


From: Huang Ying <ying.huang@xxxxxxxxx>

Some firmware will access memory in ACPI NVS region via APEI. That
is, instructions in APEI ERST/EINJ table will read/write ACPI NVS
region. The original resource conflict checking in APEI code will
check memory/ioport accessed by APEI via general resource management
mechanism. But ACPI NVS region is marked as busy already, so that the
false resource conflict will prevent APEI ERST/EINJ to work.

To fix this, this patch record ACPI NVS regions, so that we can avoid
request resources for memory region inside it.

Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx>
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
---
arch/x86/kernel/e820.c | 4 +-
drivers/acpi/Makefile | 3 +-
drivers/acpi/nvs.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++-
include/linux/acpi.h | 20 ++++++++++++-----
4 files changed, 70 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 303a0e4..51c3b18 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -714,7 +714,7 @@ void __init e820_mark_nosave_regions(unsigned long limit_pfn)
}
#endif

-#ifdef CONFIG_HIBERNATION
+#ifdef CONFIG_ACPI
/**
* Mark ACPI NVS memory region, so that we can save/restore it during
* hibernation and the subsequent resume.
@@ -727,7 +727,7 @@ static int __init e820_mark_nvs_memory(void)
struct e820entry *ei = &e820.map[i];

if (ei->type == E820_NVS)
- suspend_nvs_register(ei->addr, ei->size);
+ acpi_nvs_register(ei->addr, ei->size);
}

return 0;
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index ecb26b4..c07f44f 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -20,11 +20,12 @@ obj-y += acpi.o \
# All the builtin files are in the "acpi." module_param namespace.
acpi-y += osl.o utils.o reboot.o
acpi-y += atomicio.o
+acpi-y += nvs.o

# sleep related files
acpi-y += wakeup.o
acpi-y += sleep.o
-acpi-$(CONFIG_ACPI_SLEEP) += proc.o nvs.o
+acpi-$(CONFIG_ACPI_SLEEP) += proc.o


#
diff --git a/drivers/acpi/nvs.c b/drivers/acpi/nvs.c
index 096787b..7a2035f 100644
--- a/drivers/acpi/nvs.c
+++ b/drivers/acpi/nvs.c
@@ -15,6 +15,56 @@
#include <linux/acpi_io.h>
#include <acpi/acpiosxf.h>

+/* ACPI NVS regions, APEI may use it */
+
+struct nvs_region {
+ __u64 phys_start;
+ __u64 size;
+ struct list_head node;
+};
+
+static LIST_HEAD(nvs_region_list);
+
+#ifdef CONFIG_ACPI_SLEEP
+static int suspend_nvs_register(unsigned long start, unsigned long size);
+#else
+static inline int suspend_nvs_register(unsigned long a, unsigned long b)
+{
+ return 0;
+}
+#endif
+
+int acpi_nvs_register(__u64 start, __u64 size)
+{
+ struct nvs_region *region;
+
+ region = kmalloc(sizeof(*region), GFP_KERNEL);
+ if (!region)
+ return -ENOMEM;
+ region->phys_start = start;
+ region->size = size;
+ list_add_tail(&region->node, &nvs_region_list);
+
+ return suspend_nvs_register(start, size);
+}
+
+int acpi_nvs_for_each_region(int (*func)(__u64 start, __u64 size, void *data),
+ void *data)
+{
+ int rc;
+ struct nvs_region *region;
+
+ list_for_each_entry(region, &nvs_region_list, node) {
+ rc = func(region->phys_start, region->size, data);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
+
+#ifdef CONFIG_ACPI_SLEEP
/*
* Platforms, like ACPI, may want us to save some memory used by them during
* suspend and to restore the contents of this memory during the subsequent
@@ -41,7 +91,7 @@ static LIST_HEAD(nvs_list);
* things so that the data from page-aligned addresses in this region will
* be copied into separate RAM pages.
*/
-int suspend_nvs_register(unsigned long start, unsigned long size)
+static int suspend_nvs_register(unsigned long start, unsigned long size)
{
struct nvs_page *entry, *next;

@@ -159,3 +209,4 @@ void suspend_nvs_restore(void)
if (entry->data)
memcpy(entry->kaddr, entry->data, entry->size);
}
+#endif
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 6001b4da..26b7544 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -306,6 +306,11 @@ extern acpi_status acpi_pci_osc_control_set(acpi_handle handle,
u32 *mask, u32 req);
extern void acpi_early_init(void);

+extern int acpi_nvs_register(__u64 start, __u64 size);
+
+extern int acpi_nvs_for_each_region(int (*func)(__u64, __u64, void *),
+ void *data);
+
#else /* !CONFIG_ACPI */

#define acpi_disabled 1
@@ -348,15 +353,18 @@ static inline int acpi_table_parse(char *id,
{
return -1;
}
-#endif /* !CONFIG_ACPI */

-#ifdef CONFIG_ACPI_SLEEP
-int suspend_nvs_register(unsigned long start, unsigned long size);
-#else
-static inline int suspend_nvs_register(unsigned long a, unsigned long b)
+static inline int acpi_nvs_register(__u64 start, __u64 size)
{
return 0;
}
-#endif
+
+static inline int acpi_nvs_for_each_region(int (*func)(__u64, __u64, void *),
+ void *data)
+{
+ return 0;
+}
+
+#endif /* !CONFIG_ACPI */

#endif /*_LINUX_ACPI_H*/
--
1.7.9.rc1

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