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>
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 9bd5612..d390a0f 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -390,21 +390,17 @@
(executable_stack == EXSTACK_DEFAULT && VM_STACK_FLAGS & VM_EXEC))
stack_prot |= PROT_EXEC;
- down_write(¤t->mm->mmap_sem);
- current->mm->start_brk = do_mmap(NULL, 0, stack_size, stack_prot,
+ current->mm->start_brk = vm_mmap(NULL, 0, stack_size, stack_prot,
MAP_PRIVATE | MAP_ANONYMOUS |
MAP_UNINITIALIZED | MAP_GROWSDOWN,
0);
if (IS_ERR_VALUE(current->mm->start_brk)) {
- up_write(¤t->mm->mmap_sem);
retval = current->mm->start_brk;
current->mm->start_brk = 0;
goto error_kill;
}
- up_write(¤t->mm->mmap_sem);
-
current->mm->brk = current->mm->start_brk;
current->mm->context.end_brk = current->mm->start_brk;
current->mm->context.end_brk +=
@@ -955,10 +951,8 @@
if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
mflags |= MAP_EXECUTABLE;
- down_write(&mm->mmap_sem);
- maddr = do_mmap(NULL, load_addr, top - base,
+ maddr = vm_mmap(NULL, load_addr, top - base,
PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 0);
- up_write(&mm->mmap_sem);
if (IS_ERR_VALUE(maddr))
return (int) maddr;
@@ -1096,10 +1090,8 @@
/* create the mapping */
disp = phdr->p_vaddr & ~PAGE_MASK;
- down_write(&mm->mmap_sem);
- maddr = do_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,
+ maddr = vm_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,
phdr->p_offset - disp);
- up_write(&mm->mmap_sem);
kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx",
loop, phdr->p_memsz + disp, prot, flags,
@@ -1143,10 +1135,8 @@
unsigned long xmaddr;
flags |= MAP_FIXED | MAP_ANONYMOUS;
- down_write(&mm->mmap_sem);
- xmaddr = do_mmap(NULL, xaddr, excess - excess1,
+ xmaddr = vm_mmap(NULL, xaddr, excess - excess1,
prot, flags, 0);
- up_write(&mm->mmap_sem);
kdebug("mmap[%d] <anon>"
" ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",