From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C64D0C2BA83 for ; Fri, 14 Feb 2020 17:06:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9568020656 for ; Fri, 14 Feb 2020 17:06:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581699964; bh=F7juY/Ro+6DNKuswFBepbFfkzgLEJrYxcl6Pfk6p+wc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xq4rLxXV8EL4t3FzvSThOEckTWP7HCNUbXQ4M++3EJ7Gw1W7EJ3AYTHG+aVRi/7ey /j2CkA/Ct1QkRy+Uns0mvuQchy3D96gaQPhkR745lh+dS5+Xc4OW1CxSj7NWmk6tYW EXVJlm9weQ6eA6E9IBQyqBsT8LAd2DqPDc0uGSuw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387637AbgBNRGD (ORCPT ); Fri, 14 Feb 2020 12:06:03 -0500 Received: from mail-pg1-f193.google.com ([209.85.215.193]:34131 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388586AbgBNRGA (ORCPT ); Fri, 14 Feb 2020 12:06:00 -0500 Received: by mail-pg1-f193.google.com with SMTP id j4so5264194pgi.1; Fri, 14 Feb 2020 09:06:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=YcmNAmrbG8b4Q1zbELocvrBQuIWTW45ghRZPxCURlKs=; b=LGkW4u1S5E8xLFpgR5v7sW2j06MK3yVNHxU7BxIbb9dw1hQNkkR9C95XGIutlBVZOy j8OibtW7kRPNZT2UUXzy9Dgv2DDs1BGd0VUrSg2/0vA8DUg/j32AxBQ2C7RdXdwvUXNL zHKcDvcx+gPUB5hUFZait/vJHSaLNM2JvzhGrVil3ImfSx1lp50ncoYm1Wd3OgrjHAd1 xpd0FtDIbiOYHB4Rkp7zI1TWkowpx1OzmcdbBlOjAKznDFnzI4hJfkYd7ctzMoxlg72/ nJ8yoXws8+0Bd6iILckuNlmrBEVs2h5EdCTqLg1zaNHAj3k2CYrsO/InLKrbGbiVOPj9 vJzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=YcmNAmrbG8b4Q1zbELocvrBQuIWTW45ghRZPxCURlKs=; b=IJ9sEJG1BHTw6D0S8RsfKjCQmyd8vitb/aMTAMQaTNM0Zb6SPybOVFucuFuePtT+1Y s2Q/jVlNhn9MqjU1ty/rtlJYnJ3jLh+gRHJTXlpYpaE1OO/JSD6dQ8GPCLOJZnUeZz3g YOahr+q41D8DMDP5q9mVP1FzVh5WYg2Z+IGgvef5vYdr6iVcTt2iBYALRIu5xbyvEJjq 68zj176KAitdEcv9YER6bl8n7f/J6aP1AMOMXDgCRWy+PYJ+KJ7tzU0htptFMX6a5Hof NWUuPqj09pxwIQQc4eA9yQA1obg7BUu+v6TXrFspTbqO22SWA+fbtMyzRkK0BzGApQQB 7L4w== X-Gm-Message-State: APjAAAUBz1Dxjtv0o7+9aC42q+KjxZO1OPZ/crktHCpUsms+MSNlFeGZ CzR3AIDaUO0ep2++t/BJnVA= X-Google-Smtp-Source: APXvYqwqHc9Z5itNolbOM6+dAnfpFmB5PRq+nvJ3VvlFX7h3R8ChYUzXC6dGwCHonYwcsiCsEH02xA== X-Received: by 2002:a63:86c2:: with SMTP id x185mr4373491pgd.245.1581699959469; Fri, 14 Feb 2020 09:05:59 -0800 (PST) Received: from bbox-1.mtv.corp.google.com ([2620:15c:211:1:3e01:2939:5992:52da]) by smtp.gmail.com with ESMTPSA id a13sm7662924pfg.65.2020.02.14.09.05.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 14 Feb 2020 09:05:51 -0800 (PST) From: Minchan Kim To: Andrew Morton Cc: LKML , linux-mm , linux-api@vger.kernel.org, oleksandr@redhat.com, Suren Baghdasaryan , Tim Murray , Daniel Colascione , Sandeep Patil , Sonny Rao , Brian Geffon , Michal Hocko , Johannes Weiner , Shakeel Butt , John Dias , Joel Fernandes , sj38.park@gmail.com, alexander.h.duyck@linux.intel.com, Jann Horn , Minchan Kim Subject: [PATCH v5 1/7] mm: pass task and mm to do_madvise Date: Fri, 14 Feb 2020 09:05:14 -0800 Message-Id: <20200214170520.160271-2-minchan@kernel.org> X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog In-Reply-To: <20200214170520.160271-1-minchan@kernel.org> References: <20200214170520.160271-1-minchan@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-api-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org In upcoming patches, do_madvise will be called from external process context so we shouldn't asssume "current" is always hinted process's task_struct. Furthermore, we couldn't access mm_struct via task->mm once it's verified by access_mm which will be introduced in next patch[1]. And let's pass *current* and current->mm as arguments of do_madvise so it shouldn't change existing behavior but prepare next patch to make review easy. [1] http://lore.kernel.org/r/CAG48ez27=pwm5m_N_988xT1huO7g7h6arTQL44zev6TD-h-7Tg@mail.gmail.com Cc: Jann Horn Signed-off-by: Minchan Kim --- fs/io_uring.c | 2 +- include/linux/mm.h | 3 ++- mm/madvise.c | 34 +++++++++++++++++++--------------- 3 files changed, 22 insertions(+), 17 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 63beda9bafc5..bf111675307c 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2736,7 +2736,7 @@ static int io_madvise(struct io_kiocb *req, struct io_kiocb **nxt, if (force_nonblock) return -EAGAIN; - ret = do_madvise(ma->addr, ma->len, ma->advice); + ret = do_madvise(current, current->mm, ma->addr, ma->len, ma->advice); if (ret < 0) req_set_fail_links(req); io_cqring_add_event(req, ret); diff --git a/include/linux/mm.h b/include/linux/mm.h index 52269e56c514..beb9259f9ed1 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2323,7 +2323,8 @@ extern int __do_munmap(struct mm_struct *, unsigned long, size_t, struct list_head *uf, bool downgrade); extern int do_munmap(struct mm_struct *, unsigned long, size_t, struct list_head *uf); -extern int do_madvise(unsigned long start, size_t len_in, int behavior); +extern int do_madvise(struct task_struct *task, struct mm_struct *mm, + unsigned long start, size_t len_in, int behavior); static inline unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, diff --git a/mm/madvise.c b/mm/madvise.c index 43b47d3fae02..24566f59b89b 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -254,6 +254,7 @@ static long madvise_willneed(struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end) { + struct mm_struct *mm = vma->vm_mm; struct file *file = vma->vm_file; loff_t offset; @@ -288,12 +289,12 @@ static long madvise_willneed(struct vm_area_struct *vma, */ *prev = NULL; /* tell sys_madvise we drop mmap_sem */ get_file(file); - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); offset = (loff_t)(start - vma->vm_start) + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED); fput(file); - down_read(¤t->mm->mmap_sem); + down_read(&mm->mmap_sem); return 0; } @@ -676,7 +677,6 @@ static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, if (nr_swap) { if (current->mm == mm) sync_mm_rss(mm); - add_mm_counter(mm, MM_SWAPENTS, nr_swap); } arch_leave_lazy_mmu_mode(); @@ -756,6 +756,8 @@ static long madvise_dontneed_free(struct vm_area_struct *vma, unsigned long start, unsigned long end, int behavior) { + struct mm_struct *mm = vma->vm_mm; + *prev = vma; if (!can_madv_lru_vma(vma)) return -EINVAL; @@ -763,8 +765,8 @@ static long madvise_dontneed_free(struct vm_area_struct *vma, if (!userfaultfd_remove(vma, start, end)) { *prev = NULL; /* mmap_sem has been dropped, prev is stale */ - down_read(¤t->mm->mmap_sem); - vma = find_vma(current->mm, start); + down_read(&mm->mmap_sem); + vma = find_vma(mm, start); if (!vma) return -ENOMEM; if (start < vma->vm_start) { @@ -818,6 +820,7 @@ static long madvise_remove(struct vm_area_struct *vma, loff_t offset; int error; struct file *f; + struct mm_struct *mm = vma->vm_mm; *prev = NULL; /* tell sys_madvise we drop mmap_sem */ @@ -845,13 +848,13 @@ static long madvise_remove(struct vm_area_struct *vma, get_file(f); if (userfaultfd_remove(vma, start, end)) { /* mmap_sem was not released by userfaultfd_remove() */ - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); } error = vfs_fallocate(f, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, offset, end - start); fput(f); - down_read(¤t->mm->mmap_sem); + down_read(&mm->mmap_sem); return error; } @@ -1044,7 +1047,8 @@ madvise_behavior_valid(int behavior) * -EBADF - map exists, but area maps something that isn't a file. * -EAGAIN - a kernel resource was temporarily unavailable. */ -int do_madvise(unsigned long start, size_t len_in, int behavior) +int do_madvise(struct task_struct *task, struct mm_struct *mm, + unsigned long start, size_t len_in, int behavior) { unsigned long end, tmp; struct vm_area_struct *vma, *prev; @@ -1082,10 +1086,10 @@ int do_madvise(unsigned long start, size_t len_in, int behavior) write = madvise_need_mmap_write(behavior); if (write) { - if (down_write_killable(¤t->mm->mmap_sem)) + if (down_write_killable(&mm->mmap_sem)) return -EINTR; } else { - down_read(¤t->mm->mmap_sem); + down_read(&mm->mmap_sem); } /* @@ -1093,7 +1097,7 @@ int do_madvise(unsigned long start, size_t len_in, int behavior) * ranges, just ignore them, but return -ENOMEM at the end. * - different from the way of handling in mlock etc. */ - vma = find_vma_prev(current->mm, start, &prev); + vma = find_vma_prev(mm, start, &prev); if (vma && start > vma->vm_start) prev = vma; @@ -1130,19 +1134,19 @@ int do_madvise(unsigned long start, size_t len_in, int behavior) if (prev) vma = prev->vm_next; else /* madvise_remove dropped mmap_sem */ - vma = find_vma(current->mm, start); + vma = find_vma(mm, start); } out: blk_finish_plug(&plug); if (write) - up_write(¤t->mm->mmap_sem); + up_write(&mm->mmap_sem); else - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); return error; } SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) { - return do_madvise(start, len_in, behavior); + return do_madvise(current, current->mm, start, len_in, behavior); } -- 2.25.0.265.gbab2e86ba0-goog