diff options
author | rogersb11 <brettrogers11@gmail.com> | 2015-11-10 11:19:31 -0600 |
---|---|---|
committer | rogersb11 <brettrogers11@gmail.com> | 2015-11-10 14:01:25 -0500 |
commit | b4d16f70c34ecb908c8a61e58ea51fecdd4a4b10 (patch) | |
tree | 973e9aeb97bb13497d17a43e6f3c070381bc5b87 /mm/memory.c | |
parent | d177fbc2f0c263b06c18bda2eb46200a31bcbebd (diff) | |
parent | 5dba9ddd98cbc7ad319d687887981a0ea0062c75 (diff) | |
download | kernel_samsung_smdk4412-b4d16f70c34ecb908c8a61e58ea51fecdd4a4b10.zip kernel_samsung_smdk4412-b4d16f70c34ecb908c8a61e58ea51fecdd4a4b10.tar.gz kernel_samsung_smdk4412-b4d16f70c34ecb908c8a61e58ea51fecdd4a4b10.tar.bz2 |
Merge remote-tracking branch 'korg/linux-3.0.y' into cm-13.0
Conflicts:
crypto/algapi.c
drivers/gpu/drm/i915/i915_debugfs.c
drivers/gpu/drm/i915/intel_display.c
drivers/video/fbmem.c
include/linux/nls.h
kernel/cgroup.c
kernel/signal.c
kernel/timeconst.pl
net/ipv4/ping.c
Change-Id: I1f532925d1743df74d66bcdd6fc92f05c72ee0dd
Diffstat (limited to 'mm/memory.c')
-rw-r--r-- | mm/memory.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/mm/memory.c b/mm/memory.c index 6204ce2..5331e67 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2374,6 +2374,53 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, } EXPORT_SYMBOL(remap_pfn_range); +/** + * vm_iomap_memory - remap memory to userspace + * @vma: user vma to map to + * @start: start of area + * @len: size of area + * + * This is a simplified io_remap_pfn_range() for common driver use. The + * driver just needs to give us the physical memory range to be mapped, + * we'll figure out the rest from the vma information. + * + * NOTE! Some drivers might want to tweak vma->vm_page_prot first to get + * whatever write-combining details or similar. + */ +int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len) +{ + unsigned long vm_len, pfn, pages; + + /* Check that the physical memory area passed in looks valid */ + if (start + len < start) + return -EINVAL; + /* + * You *really* shouldn't map things that aren't page-aligned, + * but we've historically allowed it because IO memory might + * just have smaller alignment. + */ + len += start & ~PAGE_MASK; + pfn = start >> PAGE_SHIFT; + pages = (len + ~PAGE_MASK) >> PAGE_SHIFT; + if (pfn + pages < pfn) + return -EINVAL; + + /* We start the mapping 'vm_pgoff' pages into the area */ + if (vma->vm_pgoff > pages) + return -EINVAL; + pfn += vma->vm_pgoff; + pages -= vma->vm_pgoff; + + /* Can we fit all of the mapping? */ + vm_len = vma->vm_end - vma->vm_start; + if (vm_len >> PAGE_SHIFT > pages) + return -EINVAL; + + /* Ok, let it rip */ + return io_remap_pfn_range(vma, vma->vm_start, pfn, vm_len, vma->vm_page_prot); +} +EXPORT_SYMBOL(vm_iomap_memory); + static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, unsigned long addr, unsigned long end, pte_fn_t fn, void *data) |