diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-04-21 02:13:58 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-04-21 02:29:13 +0200 |
commit | 6be5ceb02e98eaf6cfc4f8b12a896d04023f340d (patch) | |
tree | f34de1392300bbf63549f4eeb20f7606d6f7b1f9 /mm/nommu.c | |
parent | VM: add "vm_munmap()" helper function (diff) | |
download | linux-6be5ceb02e98eaf6cfc4f8b12a896d04023f340d.tar.xz linux-6be5ceb02e98eaf6cfc4f8b12a896d04023f340d.zip |
VM: add "vm_mmap()" helper function
This continues the theme started with vm_brk() and vm_munmap():
vm_mmap() does the same thing as do_mmap(), but additionally does the
required VM locking.
This uninlines (and rewrites it to be clearer) do_mmap(), which sadly
duplicates it in mm/mmap.c and mm/nommu.c. But that way we don't have
to export our internal do_mmap_pgoff() function.
Some day we hopefully don't have to export do_mmap() either, if all
modular users can become the simpler vm_mmap() instead. We're actually
very close to that already, with the notable exception of the (broken)
use in i810, and a couple of stragglers in binfmt_elf.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
-rw-r--r-- | mm/nommu.c | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/mm/nommu.c b/mm/nommu.c index 11a69b22bd4b..dd00383be2d9 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1233,7 +1233,7 @@ enomem: /* * handle mapping creation for uClinux */ -unsigned long do_mmap_pgoff(struct file *file, +static unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, unsigned long len, unsigned long prot, @@ -1470,7 +1470,32 @@ error_getting_region: show_free_areas(0); return -ENOMEM; } -EXPORT_SYMBOL(do_mmap_pgoff); + +unsigned long do_mmap(struct file *file, unsigned long addr, + unsigned long len, unsigned long prot, + unsigned long flag, unsigned long offset) +{ + if (unlikely(offset + PAGE_ALIGN(len) < offset)) + return -EINVAL; + if (unlikely(offset & ~PAGE_MASK)) + return -EINVAL; + return do_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT); +} +EXPORT_SYMBOL(do_mmap); + +unsigned long vm_mmap(struct file *file, unsigned long addr, + unsigned long len, unsigned long prot, + unsigned long flag, unsigned long offset) +{ + unsigned long ret; + struct mm_struct *mm = current->mm; + + down_write(&mm->mmap_sem); + ret = do_mmap(file, addr, len, prot, flag, offset); + up_write(&mm->mmap_sem); + return ret; +} +EXPORT_SYMBOL(vm_mmap); SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, unsigned long, prot, unsigned long, flags, |