From patchwork Wed Feb 19 01:44:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Minchan Kim X-Patchwork-Id: 11390189 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DB57492A for ; Wed, 19 Feb 2020 01:44:42 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8DCEF24655 for ; Wed, 19 Feb 2020 01:44:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WaRaAenO" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8DCEF24655 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 607C66B0006; Tue, 18 Feb 2020 20:44:41 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 58D3B6B0007; Tue, 18 Feb 2020 20:44:41 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3E0786B0008; Tue, 18 Feb 2020 20:44:41 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0228.hostedemail.com [216.40.44.228]) by kanga.kvack.org (Postfix) with ESMTP id 263A36B0006 for ; Tue, 18 Feb 2020 20:44:41 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id BA847181AEF0B for ; Wed, 19 Feb 2020 01:44:40 +0000 (UTC) X-FDA: 76505182320.28.ocean56_62faaba33dd3d X-Spam-Summary: 2,0,0,d500bbab10ab0fc8,d41d8cd98f00b204,minchan.kim@gmail.com,:akpm@linux-foundation.org:linux-kernel@vger.kernel.org::linux-api@vger.kernel.org:oleksandr@redhat.com:surenb@google.com:timmurray@google.com:dancol@google.com:sspatil@google.com:sonnyrao@google.com:bgeffon@google.com:mhocko@suse.com:hannes@cmpxchg.org:shakeelb@google.com:joaodias@google.com:joel@joelfernandes.org:sj38.park@gmail.com:alexander.h.duyck@linux.intel.com:jannh@google.com:minchan@kernel.org:axboe@kernel.dk,RULES_HIT:1:2:41:69:355:379:541:617:800:960:966:967:968:973:988:989:1260:1263:1311:1314:1345:1359:1431:1437:1515:1605:1730:1747:1777:1792:2196:2199:2376:2393:2525:2559:2563:2682:2685:2693:2859:2901:2911:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3872:3874:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4049:4250:4321:4385:4425:4605:5007:6261:6653:6742:7875:7901:7903:9025:9592:10004:11026:11257:11473:11658:11914:12043:12296:122 97:12438 X-HE-Tag: ocean56_62faaba33dd3d X-Filterd-Recvd-Size: 10103 Received: from mail-pg1-f195.google.com (mail-pg1-f195.google.com [209.85.215.195]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Wed, 19 Feb 2020 01:44:40 +0000 (UTC) Received: by mail-pg1-f195.google.com with SMTP id z12so11899465pgl.4 for ; Tue, 18 Feb 2020 17:44:40 -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=U441bp8yLD7zhTeaUoTB6L8WmIONwt6EuO7mCtDR3jk=; b=WaRaAenOs0MDGImoHYFoaLaHA86WLxPhfJpdaqXi7bRQfARrfzoWMPFt/AwW47E5BL uY31jClnXdOu612TR8Tz6xj9WFVDsQ3xrzLcAQRtZ6o2QAJvkewwsQDuA0o+ZB/i4xmP c9tUYM/MAgRgsbMr9P30t6OUirkxdmxYedxTvpn9hpkRMi9hshZIGoxHCLlH6NuB3QBa ADjstIoi+3sn4uQhXCoS7ksF4oy54nan6DwPamwt7XLWrZPh783Z8Q4yO/qOUlqVS6Ly riUuVOtuCFhUX9cqmK8g2VJ9zgWHj4q4OYPdu5eN2yvs8l1Pf/blQHMvH/PryuHpNb1l k3QA== 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=U441bp8yLD7zhTeaUoTB6L8WmIONwt6EuO7mCtDR3jk=; b=Ehs3Kt9dWZ54Yig2fXoHIX4aVMa8PaxqeQWooXY1JaAkBa317P9+MY/C/OKYcjOsYU I3BguoH09Ec17mzdNpUUB/nvDOVNL9Hz5ZbNYNgjeS5Umf9drD8wK+OowTxPXCyt76fl lxEWZwGibKCVDpOcMl5yaaXkSVF8iJ5Zpg6PWgGAIY/4ypdW/tiHzP7/b1hGVGHbAkm5 Y0boK3azvDJ2No9rURYraROQIv9NFNW65F7qD3Nv4Qolowq4clCYr8i4pLOmgWl48hS3 x1NEYQz5n5otFIYIsIQE1OTG8NL+4n1fCK73g7BterGZd6IFuuheKCkmScdk1w9w4YNx HkmA== X-Gm-Message-State: APjAAAUoajYKh2/a5Vth5iTph4qr+Ed9V3rtYesFAgLNi/R40Bn6imlU kmwW0/OQJMm514qBIpUjeqk= X-Google-Smtp-Source: APXvYqzXq/OZnK3iB4xbrIIkSj/5cY2MpiGhd7fHIV0eCy3l9wmAbFQmykZPiLaW86rgiwOFJGnpYQ== X-Received: by 2002:a62:f251:: with SMTP id y17mr25166200pfl.204.1582076678946; Tue, 18 Feb 2020 17:44:38 -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 t186sm221192pgd.26.2020.02.18.17.44.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Feb 2020 17:44:37 -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 , Jens Axboe Subject: [PATCH v6 1/7] mm: pass task and mm to do_madvise Date: Tue, 18 Feb 2020 17:44:27 -0800 Message-Id: <20200219014433.88424-2-minchan@kernel.org> X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog In-Reply-To: <20200219014433.88424-1-minchan@kernel.org> References: <20200219014433.88424-1-minchan@kernel.org> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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. Note: io_madvise pass NULL as target_task argument of do_madvise because it couldn't know who is target. [1] http://lore.kernel.org/r/CAG48ez27=pwm5m_N_988xT1huO7g7h6arTQL44zev6TD-h-7Tg@mail.gmail.com Cc: Jens Axboe Cc: Jann Horn Signed-off-by: Minchan Kim Reviewed-by: Suren Baghdasaryan --- 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..a858da2ae2f4 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(NULL, req->work.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..bc16c8774328 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 *target_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..f75c86b6c463 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 *target_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); }