summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/acpi/atomicio.c41
1 files changed, 37 insertions, 4 deletions
diff --git a/drivers/acpi/atomicio.c b/drivers/acpi/atomicio.c
index 1016f186c17..d4a5b3d3657 100644
--- a/drivers/acpi/atomicio.c
+++ b/drivers/acpi/atomicio.c
@@ -32,6 +32,8 @@
#include <linux/rculist.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
#include <acpi/atomicio.h>
#define ACPI_PFX "ACPI: "
@@ -97,6 +99,37 @@ static void __iomem *__acpi_try_ioremap(phys_addr_t paddr,
return NULL;
}
+#ifndef CONFIG_IA64
+#define should_use_kmap(pfn) page_is_ram(pfn)
+#else
+/* ioremap will take care of cache attributes */
+#define should_use_kmap(pfn) 0
+#endif
+
+static void __iomem *acpi_map(phys_addr_t pg_off, unsigned long pg_sz)
+{
+ unsigned long pfn;
+
+ pfn = pg_off >> PAGE_SHIFT;
+ if (should_use_kmap(pfn)) {
+ if (pg_sz > PAGE_SIZE)
+ return NULL;
+ return (void __iomem __force *)kmap(pfn_to_page(pfn));
+ } else
+ return ioremap(pg_off, pg_sz);
+}
+
+static void acpi_unmap(phys_addr_t pg_off, void __iomem *vaddr)
+{
+ unsigned long pfn;
+
+ pfn = pg_off >> PAGE_SHIFT;
+ if (page_is_ram(pfn))
+ kunmap(pfn_to_page(pfn));
+ else
+ iounmap(vaddr);
+}
+
/*
* Used to pre-map the specified IO memory area. First try to find
* whether the area is already pre-mapped, if it is, increase the
@@ -119,7 +152,7 @@ static void __iomem *acpi_pre_map(phys_addr_t paddr,
pg_off = paddr & PAGE_MASK;
pg_sz = ((paddr + size + PAGE_SIZE - 1) & PAGE_MASK) - pg_off;
- vaddr = ioremap(pg_off, pg_sz);
+ vaddr = acpi_map(pg_off, pg_sz);
if (!vaddr)
return NULL;
map = kmalloc(sizeof(*map), GFP_KERNEL);
@@ -135,7 +168,7 @@ static void __iomem *acpi_pre_map(phys_addr_t paddr,
vaddr = __acpi_try_ioremap(paddr, size);
if (vaddr) {
spin_unlock_irqrestore(&acpi_iomaps_lock, flags);
- iounmap(map->vaddr);
+ acpi_unmap(pg_off, map->vaddr);
kfree(map);
return vaddr;
}
@@ -144,7 +177,7 @@ static void __iomem *acpi_pre_map(phys_addr_t paddr,
return map->vaddr + (paddr - map->paddr);
err_unmap:
- iounmap(vaddr);
+ acpi_unmap(pg_off, vaddr);
return NULL;
}
@@ -177,7 +210,7 @@ static void acpi_post_unmap(phys_addr_t paddr, unsigned long size)
return;
synchronize_rcu();
- iounmap(map->vaddr);
+ acpi_unmap(map->paddr, map->vaddr);
kfree(map);
}