From: Ian Pratt <Ian.Pratt@cl.cam.ac.uk>
This patch adds ARCH_HAS_DEV_MEM, enabling per-architecture implementations of
/dev/mem and thus avoids a number of messy #ifdef's. Although the mmap case
can be solved easily be simply using io_remap_page_range instead of
remap_pfn_range on all architecutres, we need to support read/write of
/dev/mem in order for dmidecode etc to work. These changes are more messy,
and we believe warrant making /dev/mem arch specific, which also cleans up
uncached_access too.
Signed-off-by: Ian Pratt <Ian.Pratt@cl.cam.ac.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/char/mem.c | 11 ++++++++---
1 files changed, 8 insertions(+), 3 deletions(-)
diff -puN drivers/char/mem.c~xen-vmm-4-has_arch_dev_mem drivers/char/mem.c
--- 25/drivers/char/mem.c~xen-vmm-4-has_arch_dev_mem 2005-02-28 18:04:43.000000000 -0800
+++ 25-akpm/drivers/char/mem.c 2005-02-28 18:07:50.000000000 -0800
@@ -111,6 +111,7 @@ static inline int valid_phys_addr_range(
}
#endif
+#ifndef ARCH_HAS_DEV_MEM
/*
* This funcion reads the *physical* memory. The f_pos points directly to the
* memory location.
@@ -231,8 +232,9 @@ static ssize_t write_mem(struct file * f
*ppos += written;
return written;
}
+#endif /* ARCH_HAS_DEV_MEM */
-static int mmap_mem(struct file * file, struct vm_area_struct * vma)
+static int mmap_kmem(struct file *file, struct vm_area_struct *vma)
{
#ifdef pgprot_noncached
unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
@@ -399,7 +401,6 @@ do_write_kmem(void *p, unsigned long rea
return written;
}
-
/*
* This function writes to the *virtual* memory as seen by the kernel.
*/
@@ -690,7 +691,7 @@ static int open_port(struct inode * inod
return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
}
-#define mmap_kmem mmap_mem
+#define mmap_mem mmap_kmem
#define zero_lseek null_lseek
#define full_lseek null_lseek
#define write_zero write_null
@@ -698,6 +699,7 @@ static int open_port(struct inode * inod
#define open_mem open_port
#define open_kmem open_mem
+#ifndef ARCH_HAS_DEV_MEM
static struct file_operations mem_fops = {
.llseek = memory_lseek,
.read = read_mem,
@@ -705,6 +707,9 @@ static struct file_operations mem_fops =
.mmap = mmap_mem,
.open = open_mem,
};
+#else
+extern struct file_operations mem_fops;
+#endif
static struct file_operations kmem_fops = {
.llseek = memory_lseek,
_