From e4eb1ff61b323d6141614e5458a1f53c7046ff8e Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 20 Apr 2012 15:35:40 -0700 Subject: VM: add "vm_brk()" helper function It does the same thing as "do_brk()", except it handles the VM locking too. It turns out that all external callers want that anyway, so we can make do_brk() static to just mm/mmap.c while at it. Signed-off-by: Linus Torvalds --- fs/binfmt_elf.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) (limited to 'fs/binfmt_elf.c') diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 48ffb3d..0708a0b 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -82,9 +82,7 @@ static int set_brk(unsigned long start, unsigned long end) end = ELF_PAGEALIGN(end); if (end > start) { unsigned long addr; - down_write(¤t->mm->mmap_sem); - addr = do_brk(start, end - start); - up_write(¤t->mm->mmap_sem); + addr = vm_brk(start, end - start); if (BAD_ADDR(addr)) return addr; } @@ -514,9 +512,7 @@ static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1); /* Map the last of the bss segment */ - down_write(¤t->mm->mmap_sem); - error = do_brk(elf_bss, last_bss - elf_bss); - up_write(¤t->mm->mmap_sem); + error = vm_brk(elf_bss, last_bss - elf_bss); if (BAD_ADDR(error)) goto out_close; } @@ -1072,11 +1068,8 @@ static int load_elf_library(struct file *file) len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr + ELF_MIN_ALIGN - 1); bss = eppnt->p_memsz + eppnt->p_vaddr; - if (bss > len) { - down_write(¤t->mm->mmap_sem); - do_brk(len, bss - len); - up_write(¤t->mm->mmap_sem); - } + if (bss > len) + vm_brk(len, bss - len); error = 0; out_free_ph: -- cgit v1.1 From 6be5ceb02e98eaf6cfc4f8b12a896d04023f340d Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 20 Apr 2012 17:13:58 -0700 Subject: 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 --- fs/binfmt_elf.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'fs/binfmt_elf.c') diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 0708a0b..16f7354 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -958,10 +958,8 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) and some applications "depend" upon this behavior. Since we do not have the power to recompile these, we emulate the SVr4 behavior. Sigh. */ - down_write(¤t->mm->mmap_sem); - error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, + error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC, MAP_FIXED | MAP_PRIVATE, 0); - up_write(¤t->mm->mmap_sem); } #ifdef ELF_PLAT_INIT @@ -1046,8 +1044,7 @@ static int load_elf_library(struct file *file) eppnt++; /* Now use mmap to map the library into memory. */ - down_write(¤t->mm->mmap_sem); - error = do_mmap(file, + error = vm_mmap(file, ELF_PAGESTART(eppnt->p_vaddr), (eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr)), @@ -1055,7 +1052,6 @@ static int load_elf_library(struct file *file) MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, (eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr))); - up_write(¤t->mm->mmap_sem); if (error != ELF_PAGESTART(eppnt->p_vaddr)) goto out_free_ph; -- cgit v1.1