Merge master.kernel.org:/pub/scm/linux/kernel/git/perex/alsa-current

[powerpc.git] / drivers / char / mem.c

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index b64108d..f182752 100644 (file)
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -35,10 +35,6 @@
 # include <linux/efi.h>
 #endif
 
-#if defined(CONFIG_S390_TAPE) && defined(CONFIG_S390_TAPE_CHAR)
-extern void tapechar_init(void);
-#endif
-
 /*
  * Architectures vary in how they handle caching for addresses
  * outside of main memory.
@@ -261,7 +257,11 @@ static int mmap_mem(struct file * file, struct vm_area_struct * vma)
 
 static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
 {
-        unsigned long long val;
+       unsigned long pfn;
+
+       /* Turn a kernel-virtual address into a physical page frame */
+       pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
+
        /*
         * RED-PEN: on some architectures there is more mapped memory
         * than available in mem_map which pfn_valid checks
@@ -269,10 +269,10 @@ static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
         *
         * RED-PEN: vmalloc is not supported right now.
         */
-       if (!pfn_valid(vma->vm_pgoff))
+       if (!pfn_valid(pfn))
                return -EIO;
-       val = (u64)vma->vm_pgoff << PAGE_SHIFT;
-       vma->vm_pgoff = __pa(val) >> PAGE_SHIFT;
+
+       vma->vm_pgoff = pfn;
        return mmap_mem(file, vma);
 }
 
@@ -287,7 +287,7 @@ static ssize_t read_oldmem(struct file *file, char __user *buf,
        size_t read = 0, csize;
        int rc = 0;
 
-       while(count) {
+       while (count) {
                pfn = *ppos / PAGE_SIZE;
                if (pfn > saved_max_pfn)
                        return read;