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// SPDX-License-Identifier: GPL-2.0-only
#include <linux/mm.h>
#include <linux/io-mapping.h>
/**
* io_mapping_map_user - remap an I/O mapping to userspace
* @iomap: the source io_mapping
* @vma: user vma to map to
* @addr: target user address to start at
* @pfn: physical address of kernel memory
* @size: size of map area
*
* Note: this is only safe if the mm semaphore is held when called.
*/
int io_mapping_map_user(struct io_mapping *iomap, struct vm_area_struct *vma,
unsigned long addr, unsigned long pfn, unsigned long size)
{
vm_flags_t expected_flags = VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
if (WARN_ON_ONCE((vma->vm_flags & expected_flags) != expected_flags))
return -EINVAL;
/* We rely on prevalidation of the io-mapping to skip track_pfn(). */
return remap_pfn_range_notrack(vma, addr, pfn, size,
__pgprot((pgprot_val(iomap->prot) & _PAGE_CACHE_MASK) |
(pgprot_val(vma->vm_page_prot) & ~_PAGE_CACHE_MASK)));
}
EXPORT_SYMBOL_GPL(io_mapping_map_user);
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