[089/126] vm: convert mtdchar mmap to vm_iomap_memory() helper

Steven Rostedt
2013-05-07T04:36:33Z

[-- Attachment #1: 0089-vm-convert-mtdchar-mmap-to-vm_iomap_memory-helper.patch --]
[-- Type: text/plain, Size: 2499 bytes --]

3.6.11.3 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Linus Torvalds <torvalds@linux-foundation.org>

[ Upstream commit 8558e4a26b00225efeb085725bc319f91201b239 ]

This is my example conversion of a few existing mmap users. The mtdchar
case is actually disabled right now (and stays disabled), but I did it
because it showed up on my "git grep", and I was familiar with the code
due to fixing an overflow problem in the code in commit 9c603e53d380
("mtdchar: fix offset overflow detection").

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
drivers/mtd/mtdchar.c | 32 ++------------------------------
1 file changed, 2 insertions(+), 30 deletions(-)

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 76afcb4..6e3d6dc 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -1159,45 +1159,17 @@ static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
struct map_info *map = mtd->priv;
- resource_size_t start, off;
- unsigned long len, vma_len;

/* This is broken because it assumes the MTD device is map-based
and that mtd->priv is a valid struct map_info. It should be
replaced with something that uses the mtd_get_unmapped_area()
operation properly. */
if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
- off = get_vm_offset(vma);
- start = map->phys;
- len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
- start &= PAGE_MASK;
- vma_len = get_vm_size(vma);
-
- /* Overflow in off+len? */
- if (vma_len + off < off)
- return -EINVAL;
- /* Does it fit in the mapping? */
- if (vma_len + off > len)
- return -EINVAL;
-
- off += start;
- /* Did that overflow? */
- if (off < start)
- return -EINVAL;
- if (set_vm_offset(vma, off) < 0)
- return -EINVAL;
- vma->vm_flags |= VM_IO | VM_RESERVED;
-
#ifdef pgprot_noncached
- if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
+ if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
#endif
- if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
- vma->vm_end - vma->vm_start,
- vma->vm_page_prot))
- return -EAGAIN;
-
- return 0;
+ return vm_iomap_memory(vma, map->phys, map->size);
}
return -ENOSYS;
#else
--
1.7.10.4