From dd02b67d5e9e7896891fa27eb5db65f55a290998 Mon Sep 17 00:00:00 2001 From: Anatolij Gustschin Date: Tue, 15 Jun 2010 09:30:15 +0200 Subject: [PATCH] mtd: mtdchar: fix mmap for MTD RAM/ROM char devices For no-mmu systems mmap() on RAM/ROM devices already works but for systems with mmu it probably was not tested and doesn't work. This patch allows using mmap() on MTD RAM/ROM devices on systems with MMU. It has been tested on mpc5121e based platform with MR0A16A MRAM device attached over LocalBus. Signed-off-by: Anatolij Gustschin Acked-by: Mike Frysinger Signed-off-by: David Woodhouse --- drivers/mtd/mtdchar.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c index a8e69dd2b2e4..c27e65e3e291 100644 --- a/drivers/mtd/mtdchar.c +++ b/drivers/mtd/mtdchar.c @@ -18,6 +18,7 @@ #include #include +#include #include #include @@ -955,9 +956,34 @@ static int mtd_mmap(struct file *file, struct vm_area_struct *vma) #ifdef CONFIG_MMU struct mtd_file_info *mfi = file->private_data; struct mtd_info *mtd = mfi->mtd; + struct map_info *map = mtd->priv; + unsigned long start; + unsigned long off; + u32 len; + + if (mtd->type == MTD_RAM || mtd->type == MTD_ROM) { + off = vma->vm_pgoff << PAGE_SHIFT; + start = map->phys; + len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size); + start &= PAGE_MASK; + if ((vma->vm_end - vma->vm_start + off) > len) + return -EINVAL; + + off += start; + vma->vm_pgoff = off >> PAGE_SHIFT; + vma->vm_flags |= VM_IO | VM_RESERVED; + +#ifdef pgprot_noncached + if (file->f_flags & O_DSYNC || off >= __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; - if (mtd->type == MTD_RAM || mtd->type == MTD_ROM) return 0; + } return -ENOSYS; #else return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS; -- 2.39.5