acpi/x86: introduce __apci_map_table, v4

to prevent wrongly overwriting fixmap that still want to use.

ACPI used to rely on low mappings being all linearly mapped and
grew a habit: it never really unmapped certain kinds of tables
after use.

This can cause problems - for example the hypothetical case
when some spurious access still references it.

v2: remove prev_map and prev_size in __apci_map_table
v3: let acpi_os_unmap_memory() call early_iounmap too, so remove extral calling to
early_acpi_os_unmap_memory
v4: fix typo in one acpi_get_table_with_size calling

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 2 deletions

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index b3193ec0a2ef..d1dd5160daa9 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -274,12 +274,19 @@ EXPORT_SYMBOL_GPL(acpi_os_map_memory);
 
 void acpi_os_unmap_memory(void __iomem * virt, acpi_size size)
 {
-        if (acpi_gbl_permanent_mmap) {
+        if (acpi_gbl_permanent_mmap)
                 iounmap(virt);
-        }
+        else
+                __acpi_unmap_table(virt, size);
 }
 EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
 
+void early_acpi_os_unmap_memory(void __iomem * virt, acpi_size size)
+{
+        if (!acpi_gbl_permanent_mmap)
+                __acpi_unmap_table(virt, size);
+}
+
 #ifdef ACPI_FUTURE_USAGE
 acpi_status
 acpi_os_get_physical_address(void *virt, acpi_physical_address * phys)