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_aout.c | 12 +++--------- fs/binfmt_elf.c | 8 ++------ fs/binfmt_elf_fdpic.c | 18 ++++-------------- fs/binfmt_flat.c | 12 +++--------- fs/binfmt_som.c | 12 +++--------- 5 files changed, 15 insertions(+), 47 deletions(-) (limited to 'fs') diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c index 88527492b917..d146e181d10d 100644 --- a/fs/binfmt_aout.c +++ b/fs/binfmt_aout.c @@ -319,24 +319,20 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs) goto beyond_if; } - down_write(¤t->mm->mmap_sem); - error = do_mmap(bprm->file, N_TXTADDR(ex), ex.a_text, + error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text, PROT_READ | PROT_EXEC, MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, fd_offset); - up_write(¤t->mm->mmap_sem); if (error != N_TXTADDR(ex)) { send_sig(SIGKILL, current, 0); return error; } - down_write(¤t->mm->mmap_sem); - error = do_mmap(bprm->file, N_DATADDR(ex), ex.a_data, + error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE, fd_offset + ex.a_text); - up_write(¤t->mm->mmap_sem); if (error != N_DATADDR(ex)) { send_sig(SIGKILL, current, 0); return error; @@ -417,12 +413,10 @@ static int load_aout_library(struct file *file) goto out; } /* Now use mmap to map the library into memory. */ - down_write(¤t->mm->mmap_sem); - error = do_mmap(file, start_addr, ex.a_text + ex.a_data, + error = vm_mmap(file, start_addr, ex.a_text + ex.a_data, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE, N_TXTOFF(ex)); - up_write(¤t->mm->mmap_sem); retval = error; if (error != start_addr) goto out; diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 0708a0bf0ba9..16f735417072 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; diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c index 9bd5612a8224..d390a0fffc65 100644 --- a/fs/binfmt_elf_fdpic.c +++ b/fs/binfmt_elf_fdpic.c @@ -390,21 +390,17 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm, (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 @@ static int elf_fdpic_map_file_constdisp_on_uclinux( 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 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params, /* 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] sz=%lx pr=%x fl=%x of=%lx --> %08lx", loop, phdr->p_memsz + disp, prot, flags, @@ -1143,10 +1135,8 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params, 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] " " ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx", diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index 024d20ee3ca3..6b2daf99fab8 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -542,10 +542,8 @@ static int load_flat_file(struct linux_binprm * bprm, */ DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n"); - down_write(¤t->mm->mmap_sem); - textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, + textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_EXECUTABLE, 0); - up_write(¤t->mm->mmap_sem); if (!textpos || IS_ERR_VALUE(textpos)) { if (!textpos) textpos = (unsigned long) -ENOMEM; @@ -556,10 +554,8 @@ static int load_flat_file(struct linux_binprm * bprm, len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); len = PAGE_ALIGN(len); - down_write(¤t->mm->mmap_sem); - realdatastart = do_mmap(0, 0, len, + realdatastart = vm_mmap(0, 0, len, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0); - up_write(¤t->mm->mmap_sem); if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) { if (!realdatastart) @@ -603,10 +599,8 @@ static int load_flat_file(struct linux_binprm * bprm, len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); len = PAGE_ALIGN(len); - down_write(¤t->mm->mmap_sem); - textpos = do_mmap(0, 0, len, + textpos = vm_mmap(0, 0, len, PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0); - up_write(¤t->mm->mmap_sem); if (!textpos || IS_ERR_VALUE(textpos)) { if (!textpos) diff --git a/fs/binfmt_som.c b/fs/binfmt_som.c index e4fc746629a7..4517aaff61b4 100644 --- a/fs/binfmt_som.c +++ b/fs/binfmt_som.c @@ -147,10 +147,8 @@ static int map_som_binary(struct file *file, code_size = SOM_PAGEALIGN(hpuxhdr->exec_tsize); current->mm->start_code = code_start; current->mm->end_code = code_start + code_size; - down_write(¤t->mm->mmap_sem); - retval = do_mmap(file, code_start, code_size, prot, + retval = vm_mmap(file, code_start, code_size, prot, flags, SOM_PAGESTART(hpuxhdr->exec_tfile)); - up_write(¤t->mm->mmap_sem); if (retval < 0 && retval > -1024) goto out; @@ -158,20 +156,16 @@ static int map_som_binary(struct file *file, data_size = SOM_PAGEALIGN(hpuxhdr->exec_dsize); current->mm->start_data = data_start; current->mm->end_data = bss_start = data_start + data_size; - down_write(¤t->mm->mmap_sem); - retval = do_mmap(file, data_start, data_size, + retval = vm_mmap(file, data_start, data_size, prot | PROT_WRITE, flags, SOM_PAGESTART(hpuxhdr->exec_dfile)); - up_write(¤t->mm->mmap_sem); if (retval < 0 && retval > -1024) goto out; som_brk = bss_start + SOM_PAGEALIGN(hpuxhdr->exec_bsize); current->mm->start_brk = current->mm->brk = som_brk; - down_write(¤t->mm->mmap_sem); - retval = do_mmap(NULL, bss_start, som_brk - bss_start, + retval = vm_mmap(NULL, bss_start, som_brk - bss_start, prot | PROT_WRITE, MAP_FIXED | MAP_PRIVATE, 0); - up_write(¤t->mm->mmap_sem); if (retval > 0 || retval < -1024) retval = 0; out: -- cgit