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Diffstat (limited to 'arch/x86/mm/pat.c')
-rw-r--r--arch/x86/mm/pat.c48
1 files changed, 31 insertions, 17 deletions
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 05f9aef6818a..2ed37158012d 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -11,6 +11,7 @@
#include <linux/bootmem.h>
#include <linux/debugfs.h>
#include <linux/kernel.h>
+#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/fs.h>
@@ -634,6 +635,33 @@ void unmap_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot)
}
/*
+ * Change the memory type for the physial address range in kernel identity
+ * mapping space if that range is a part of identity map.
+ */
+int kernel_map_sync_memtype(u64 base, unsigned long size, unsigned long flags)
+{
+ unsigned long id_sz;
+
+ if (!pat_enabled || base >= __pa(high_memory))
+ return 0;
+
+ id_sz = (__pa(high_memory) < base + size) ?
+ __pa(high_memory) - base :
+ size;
+
+ if (ioremap_change_attr((unsigned long)__va(base), id_sz, flags) < 0) {
+ printk(KERN_INFO
+ "%s:%d ioremap_change_attr failed %s "
+ "for %Lx-%Lx\n",
+ current->comm, current->pid,
+ cattr_name(flags),
+ base, (unsigned long long)(base + size));
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/*
* Internal interface to reserve a range of physical memory with prot.
* Reserved non RAM regions only and after successful reserve_memtype,
* this func also keeps identity mapping (if any) in sync with this new prot.
@@ -642,7 +670,7 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
int strict_prot)
{
int is_ram = 0;
- int id_sz, ret;
+ int ret;
unsigned long flags;
unsigned long want_flags = (pgprot_val(*vma_prot) & _PAGE_CACHE_MASK);
@@ -679,23 +707,8 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
flags);
}
- /* Need to keep identity mapping in sync */
- if (paddr >= __pa(high_memory))
- return 0;
-
- id_sz = (__pa(high_memory) < paddr + size) ?
- __pa(high_memory) - paddr :
- size;
-
- if (ioremap_change_attr((unsigned long)__va(paddr), id_sz, flags) < 0) {
+ if (kernel_map_sync_memtype(paddr, size, flags) < 0) {
free_memtype(paddr, paddr + size);
- printk(KERN_ERR
- "%s:%d reserve_pfn_range ioremap_change_attr failed %s "
- "for %Lx-%Lx\n",
- current->comm, current->pid,
- cattr_name(flags),
- (unsigned long long)paddr,
- (unsigned long long)(paddr + size));
return -EINVAL;
}
return 0;
@@ -877,6 +890,7 @@ pgprot_t pgprot_writecombine(pgprot_t prot)
else
return pgprot_noncached(prot);
}
+EXPORT_SYMBOL_GPL(pgprot_writecombine);
#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)