vm: convert mtdchar mmap to vm_iomap_memory() helper
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 9c603e53d3
("mtdchar: fix offset overflow detection").
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
2323036dfe
commit
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@ -1159,45 +1159,17 @@ static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
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struct mtd_file_info *mfi = file->private_data;
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struct mtd_file_info *mfi = file->private_data;
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struct mtd_info *mtd = mfi->mtd;
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struct mtd_info *mtd = mfi->mtd;
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struct map_info *map = mtd->priv;
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struct map_info *map = mtd->priv;
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resource_size_t start, off;
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unsigned long len, vma_len;
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/* This is broken because it assumes the MTD device is map-based
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/* This is broken because it assumes the MTD device is map-based
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and that mtd->priv is a valid struct map_info. It should be
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and that mtd->priv is a valid struct map_info. It should be
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replaced with something that uses the mtd_get_unmapped_area()
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replaced with something that uses the mtd_get_unmapped_area()
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operation properly. */
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operation properly. */
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if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
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if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
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off = get_vm_offset(vma);
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start = map->phys;
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len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
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start &= PAGE_MASK;
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vma_len = get_vm_size(vma);
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/* Overflow in off+len? */
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if (vma_len + off < off)
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return -EINVAL;
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/* Does it fit in the mapping? */
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if (vma_len + off > len)
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return -EINVAL;
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off += start;
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/* Did that overflow? */
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if (off < start)
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return -EINVAL;
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if (set_vm_offset(vma, off) < 0)
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return -EINVAL;
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vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
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#ifdef pgprot_noncached
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#ifdef pgprot_noncached
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if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
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if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
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vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
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vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
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#endif
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#endif
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if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
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return vm_iomap_memory(vma, map->phys, map->size);
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vma->vm_end - vma->vm_start,
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vma->vm_page_prot))
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return -EAGAIN;
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return 0;
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}
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}
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return -ENOSYS;
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return -ENOSYS;
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#else
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#else
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