Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932254Ab0AFPZn (ORCPT ); Wed, 6 Jan 2010 10:25:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932221Ab0AFPZB (ORCPT ); Wed, 6 Jan 2010 10:25:01 -0500 Received: from smtp.mujha-vel.cz ([81.30.225.246]:40224 "EHLO smtp.mujha-vel.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932223Ab0AFPY5 (ORCPT ); Wed, 6 Jan 2010 10:24:57 -0500 From: Jiri Slaby To: jirislaby@gmail.com Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton Subject: [PATCH] MM: use helpers for rlimits Date: Wed, 6 Jan 2010 16:24:36 +0100 Message-Id: <1262791479-26594-8-git-send-email-jslaby@suse.cz> X-Mailer: git-send-email 1.6.5.7 In-Reply-To: <1262791479-26594-1-git-send-email-jslaby@suse.cz> References: <1262791479-26594-1-git-send-email-jslaby@suse.cz> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5723 Lines: 166 Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. I.e. either use rlimit helpers added in 3e10e716abf3c71bdb5d86b8f507f9e72236c9cd or ACCESS_ONCE if not applicable. Signed-off-by: Jiri Slaby Cc: linux-mm@kvack.org Cc: Andrew Morton --- mm/filemap.c | 2 +- mm/mlock.c | 12 ++++++------ mm/mmap.c | 13 +++++++------ mm/mremap.c | 2 +- 4 files changed, 15 insertions(+), 14 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 96ac6b0..4450b75 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1950,7 +1950,7 @@ EXPORT_SYMBOL(iov_iter_single_seg_count); inline int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk) { struct inode *inode = file->f_mapping->host; - unsigned long limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur; + unsigned long limit = rlimit(RLIMIT_FSIZE); if (unlikely(*pos < 0)) return -EINVAL; diff --git a/mm/mlock.c b/mm/mlock.c index 2b8335a..8f4e2df 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -25,7 +25,7 @@ int can_do_mlock(void) { if (capable(CAP_IPC_LOCK)) return 1; - if (current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur != 0) + if (rlimit(RLIMIT_MEMLOCK) != 0) return 1; return 0; } @@ -487,7 +487,7 @@ SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len) locked = len >> PAGE_SHIFT; locked += current->mm->locked_vm; - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur; + lock_limit = rlimit(RLIMIT_MEMLOCK); lock_limit >>= PAGE_SHIFT; /* check against resource limits */ @@ -550,7 +550,7 @@ SYSCALL_DEFINE1(mlockall, int, flags) down_write(¤t->mm->mmap_sem); - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur; + lock_limit = rlimit(RLIMIT_MEMLOCK); lock_limit >>= PAGE_SHIFT; ret = -ENOMEM; @@ -584,7 +584,7 @@ int user_shm_lock(size_t size, struct user_struct *user) int allowed = 0; locked = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur; + lock_limit = rlimit(RLIMIT_MEMLOCK); if (lock_limit == RLIM_INFINITY) allowed = 1; lock_limit >>= PAGE_SHIFT; @@ -618,12 +618,12 @@ int account_locked_memory(struct mm_struct *mm, struct rlimit *rlim, down_write(&mm->mmap_sem); - lim = rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT; + lim = ACCESS_ONCE(rlim[RLIMIT_AS].rlim_cur) >> PAGE_SHIFT; vm = mm->total_vm + pgsz; if (lim < vm) goto out; - lim = rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT; + lim = ACCESS_ONCE(rlim[RLIMIT_MEMLOCK].rlim_cur) >> PAGE_SHIFT; vm = mm->locked_vm + pgsz; if (lim < vm) goto out; diff --git a/mm/mmap.c b/mm/mmap.c index ee22989..7805ac5 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -265,7 +265,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk) * segment grow beyond its set limit the in case where the limit is * not page aligned -Ram Gupta */ - rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur; + rlim = rlimit(RLIMIT_DATA); if (rlim < RLIM_INFINITY && (brk - mm->start_brk) + (mm->end_data - mm->start_data) > rlim) goto out; @@ -967,7 +967,7 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, unsigned long locked, lock_limit; locked = len >> PAGE_SHIFT; locked += mm->locked_vm; - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur; + lock_limit = rlimit(RLIMIT_MEMLOCK); lock_limit >>= PAGE_SHIFT; if (locked > lock_limit && !capable(CAP_IPC_LOCK)) return -EAGAIN; @@ -1599,7 +1599,7 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns return -ENOMEM; /* Stack limit test */ - if (size > rlim[RLIMIT_STACK].rlim_cur) + if (size > ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur)) return -ENOMEM; /* mlock limit tests */ @@ -1607,7 +1607,8 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns unsigned long locked; unsigned long limit; locked = mm->locked_vm + grow; - limit = rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT; + limit = ACCESS_ONCE(rlim[RLIMIT_MEMLOCK].rlim_cur); + limit >>= PAGE_SHIFT; if (locked > limit && !capable(CAP_IPC_LOCK)) return -ENOMEM; } @@ -2074,7 +2075,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len) unsigned long locked, lock_limit; locked = len >> PAGE_SHIFT; locked += mm->locked_vm; - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur; + lock_limit = rlimit(RLIMIT_MEMLOCK); lock_limit >>= PAGE_SHIFT; if (locked > lock_limit && !capable(CAP_IPC_LOCK)) return -EAGAIN; @@ -2288,7 +2289,7 @@ int may_expand_vm(struct mm_struct *mm, unsigned long npages) unsigned long cur = mm->total_vm; /* pages */ unsigned long lim; - lim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT; + lim = rlimit(RLIMIT_AS) >> PAGE_SHIFT; if (cur + npages > lim) return 0; diff --git a/mm/mremap.c b/mm/mremap.c index 8451908..4c4c803 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -285,7 +285,7 @@ static struct vm_area_struct *vma_to_resize(unsigned long addr, if (vma->vm_flags & VM_LOCKED) { unsigned long locked, lock_limit; locked = mm->locked_vm << PAGE_SHIFT; - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur; + lock_limit = rlimit(RLIMIT_MEMLOCK); locked += new_len - old_len; if (locked > lock_limit && !capable(CAP_IPC_LOCK)) goto Eagain; -- 1.6.5.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/