From: Chen Yu <yu.c.chen@xxxxxxxxx>
This patch implements acpi_os_readable(). The function is used by ACPICA
AML debugger to validate user specified pointers for dumping the memory as
ACPICA descriptor objects.
Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx>
Tested-by: Lv Zheng <lv.zheng@xxxxxxxxx>
Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx>
---
arch/x86/Kconfig | 1 +
arch/x86/include/asm/acenv.h | 1 +
arch/x86/kernel/acpi/boot.c | 44 +++++++++++++++++++++++++++++++++++++
drivers/acpi/Kconfig | 3 +++
drivers/acpi/osl.c | 12 ++++++++++
include/acpi/platform/aclinux.h | 1 -
include/acpi/platform/aclinuxex.h | 5 -----
7 files changed, 61 insertions(+), 6 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index db3622f..6593b6a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -19,6 +19,7 @@ config X86
def_bool y
select ACPI_LEGACY_TABLES_LOOKUP if ACPI
select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
+ select ACPI_MEMORY_ACCESS_CHECK_SUPPORT if ACPI
select ANON_INODES
select ARCH_CLOCKSOURCE_DATA
select ARCH_DISCARD_MEMBLOCK
diff --git a/arch/x86/include/asm/acenv.h b/arch/x86/include/asm/acenv.h
index 1b010a8..a2a2849 100644
--- a/arch/x86/include/asm/acenv.h
+++ b/arch/x86/include/asm/acenv.h
@@ -20,6 +20,7 @@
int __acpi_acquire_global_lock(unsigned int *lock);
int __acpi_release_global_lock(unsigned int *lock);
+bool __acpi_memory_readable(void *pointer, size_t length);
#define ACPI_ACQUIRE_GLOBAL_LOCK(facs, Acq) \
((Acq) = __acpi_acquire_global_lock(&facs->global_lock))
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index e759076..4a5e22e 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1699,6 +1699,50 @@ int __acpi_release_global_lock(unsigned int *lock)
return old & 0x1;
}
+bool __acpi_memory_readable(void *pointer, size_t length)
+{
+ unsigned long obj_start, obj_end;
+ unsigned long start_pfn, end_pfn;
+
+ /*
+ * All direct mapped PFNs should have been recorded by the mapped
+ * PFN ranges. But pfn_range_is_mapped() requires the following
+ * sanity checks to be performed before invoking.
+ */
+ obj_start = ACPI_TO_INTEGER(pointer);
+ obj_end = obj_start + length;
+
+ /*
+ * ACPICA core doesn't validate if the object is wrapped over, so
+ * we should.
+ */
+ if (length && (obj_end - 1) < obj_start)
+ return false;
+
+ /*
+ * None direct mapping ranges contain holes. For example, high
+ * kernel map holes (lower than _text or higher than _brk_end).
+ * Converting a virtual address that belongs to the high map hole
+ * results in a valid PFN because its low map has been recorded as
+ * a mapped range.
+ */
+ if (obj_start < PAGE_OFFSET ||
+ obj_start >= (unsigned long)high_memory ||
+ (length && (obj_end - 1) >= (unsigned long)high_memory))
+ return false;
+
+ /*
+ * It is required to pass a range (end_pfn - start_pfn > 0) to
+ * pfn_range_is_mapped().
+ */
+ start_pfn = PFN_DOWN(__pa(obj_start));
+ end_pfn = PFN_UP(__pa(obj_end));
+ if (unlikely(end_pfn == start_pfn))
+ end_pfn++;
+
+ return pfn_range_is_mapped(start_pfn, end_pfn);
+}
+
void __init arch_reserve_mem_area(acpi_physical_address addr, size_t size)
{
e820_add_region(addr, size, E820_ACPI);
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 82b96ee..9422133 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -57,6 +57,9 @@ config ACPI_SYSTEM_POWER_STATES_SUPPORT
config ACPI_CCA_REQUIRED
bool
+config ACPI_MEMORY_ACCESS_CHECK_SUPPORT
+ bool
+
config ACPI_DEBUGGER
bool "AML debugger interface"
select ACPI_DEBUG
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index bb66093..14a3beb 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -1585,6 +1585,18 @@ acpi_status acpi_os_get_line(char *buffer, u32 buffer_length, u32 *bytes_read)
}
EXPORT_SYMBOL(acpi_os_get_line);
+#ifdef CONFIG_ACPI_MEMORY_ACCESS_CHECK_SUPPORT
+u8 acpi_os_readable(void *pointer, acpi_size length)
+{
+ return __acpi_memory_readable(pointer, length) ? TRUE : FALSE;
+}
+#else
+u8 acpi_os_readable(void *pointer, acpi_size length)
+{
+ return TRUE;
+}
+#endif
+
acpi_status acpi_os_wait_command_ready(void)
{
int ret;
diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h
index e21857d..b3c493e 100644
--- a/include/acpi/platform/aclinux.h
+++ b/include/acpi/platform/aclinux.h
@@ -148,7 +148,6 @@
/*
* OSL interfaces used by debugger/disassembler
*/
-#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_readable
#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_writable
#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_initialize_command_signals
#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_terminate_command_signals
diff --git a/include/acpi/platform/aclinuxex.h b/include/acpi/platform/aclinuxex.h
index ceea026..94bead6 100644
--- a/include/acpi/platform/aclinuxex.h
+++ b/include/acpi/platform/aclinuxex.h
@@ -124,11 +124,6 @@ static inline acpi_thread_id acpi_os_get_thread_id(void)
lock ? AE_OK : AE_NO_MEMORY; \
})
-static inline u8 acpi_os_readable(void *pointer, acpi_size length)
-{
- return TRUE;
-}
-
static inline acpi_status acpi_os_initialize_command_signals(void)
{
return AE_OK;
--
1.7.10
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