From patchwork Tue Sep 11 22:34:44 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Sandoval X-Patchwork-Id: 10596425 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EDAF0112B for ; Tue, 11 Sep 2018 22:35:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DC7CE29C45 for ; Tue, 11 Sep 2018 22:35:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CEB8C29DEA; Tue, 11 Sep 2018 22:35:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 09A4329DDD for ; Tue, 11 Sep 2018 22:35:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CEAB38E0013; Tue, 11 Sep 2018 18:35:15 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id B58F28E0001; Tue, 11 Sep 2018 18:35:15 -0400 (EDT) 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 9F8578E0013; Tue, 11 Sep 2018 18:35:15 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) by kanga.kvack.org (Postfix) with ESMTP id 5846E8E0001 for ; Tue, 11 Sep 2018 18:35:15 -0400 (EDT) Received: by mail-pl1-f198.google.com with SMTP id c5-v6so12129014plo.2 for ; Tue, 11 Sep 2018 15:35:15 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=T4zypnAVQJfVK6JjN6ITEGJDUN7vtLnMURc1S60reio=; b=RqkraAE2vu2XNBuuYGlxNhriOW5ougA/h77sQ+Y5H0Uwgyf26Srv+B6i9Phg1MnAO1 PBqUT5prq8fmpE3gRe2rTmNWKyZvYg/KhvkjW/P2F37/0kZdYwCLHpDEKceLsfY7yvit zyejd+HQaWRVyj9BmJO5tkFknWXWcAMlnpAOoYdr6AXnZ5Ez3ac4Nnh0OaedsaPJSTGw 02KGgA+mE9ulLMKhjaEhPTyZThFHp/hpUwwE7GvwvB4TgHOnS1EQ0tc7LDDii33KBsdZ XaP+GE09gFeWKKoxroK4aCU9b4+qiyNHTtfqlgMkt6GNyt3210fjM+PmZ6qDV4hWXZyg iy4w== X-Gm-Message-State: APzg51BoIL3jIfrM9jy5SblUY/M2TAvJRxEB4HFW1eqdQ4/HvVW3ZwZA Fo+QfkE+FapLiGC+C2T/f+K6ETJdC2w2ZS9VxyaTUEMRqVXTCorT8JBImwxYndyd6+kiQMqPocQ L7g4l1uwroTa+QMZMwJbb4/LP4gKfKcc0BZpfC2oEJhH4VYlpKxDrQmbMGhV2Xbx7s/rb0V9VFi zpUTtDbjmLxyWCXhqMGDlVQS+UM1Ogo6nag57vInzGl3zAEWWEvkWGABq43n3oEc/7KRiK5Rfli 5DSS5W0Gd/feSdPV5vrf/r5WOl6i0sXVXnQtSCBUGPbK594DE3sp771sJUTjf5csWhDXn49vOJk GHz548njfD5TU0v6qQCUK1rZLgGUkR836rgxZ5DNtJsND9u7BQtyktAOZ6mlinqYYr3tkRDvEWj b X-Received: by 2002:a17:902:704c:: with SMTP id h12-v6mr29223169plt.237.1536705314909; Tue, 11 Sep 2018 15:35:14 -0700 (PDT) X-Received: by 2002:a17:902:704c:: with SMTP id h12-v6mr29223126plt.237.1536705314015; Tue, 11 Sep 2018 15:35:14 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1536705313; cv=none; d=google.com; s=arc-20160816; b=KKqQ5bD04aRk7xnV4NhVctqzptSiJotb2jnNOuLzG5T7Z3FmI8ZSGL/C62jixur+mP oaM7+keaQSdyTUq5nau+fdzJBig/P658kDougKUSR8ZaNbWePEosr1mGeBXK2ZlqKfqv WMm2tcqpFkH5K6xjFD6b77ybAfvignfwHQwrtITJOde3hChld0dOzGgLg1cYXRD1OVQH dLu5T+P/COJ54JpxJM4fMjQvvTh9P9WfUhUvJYpaJEg4odq1KWly3QKTXCIG3Pn7xH4k FdCOeBvt5yC4ADsfBB7wUnDBguCoOztvGjkIG/a840AiiGW6Vz/j1I4b55rFVKU6IwFo 4JiA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=T4zypnAVQJfVK6JjN6ITEGJDUN7vtLnMURc1S60reio=; b=eY8whRJQrx++eRhrST6XC7EUkAtbHFvanFU7VbaUm9D4CffpcbfXz6hj5S+aqH0iag o6/b4RLSgD6FXszf1mvAA0816qA7yj0qQie2itUOede+lYM8khjdDBdDNvm6t3lbys7u e6JCWjsEpCCQv0FLG9EJNeKitguONAOMRkBCrz7HduV5//U7LYRpM1OFPBIAONcLLGMO CfxMegqj8rzWKbLgJ+hYSIKVQMDW+o+I58m2IUtB/J8Icd1xNFoKsyMTM+Yhcbcfp0mP NIBfR5XggpPxUVROmuLRDpNQi9UG8iT4KC45/MfAyqpsG1qWTVHvGS7wmbgjRA+pOXR1 DA3A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@osandov-com.20150623.gappssmtp.com header.s=20150623 header.b=rGJqKX4G; spf=neutral (google.com: 209.85.220.65 is neither permitted nor denied by best guess record for domain of osandov@osandov.com) smtp.mailfrom=osandov@osandov.com Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id 9-v6sor3041870pgp.177.2018.09.11.15.35.13 for (Google Transport Security); Tue, 11 Sep 2018 15:35:13 -0700 (PDT) Received-SPF: neutral (google.com: 209.85.220.65 is neither permitted nor denied by best guess record for domain of osandov@osandov.com) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@osandov-com.20150623.gappssmtp.com header.s=20150623 header.b=rGJqKX4G; spf=neutral (google.com: 209.85.220.65 is neither permitted nor denied by best guess record for domain of osandov@osandov.com) smtp.mailfrom=osandov@osandov.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osandov-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=T4zypnAVQJfVK6JjN6ITEGJDUN7vtLnMURc1S60reio=; b=rGJqKX4GqOEBzI51/hVK9a/V+lrJQvJwpsuMJsxJj4VrZzqJq6FsqW3SVnr0u7ss2w 2kUdQ4qiMib5tUyKrfqE6zUAtmLN9ls1ghLQ5VpV040OoH25kokfUHpa9CbqmH5cKCrh Pf1pNiVouOyhZ1EvQ0eT/Duxc+ctu4eAMYzYhMUtJrVpKN4o/EOyzyppyy+eZZ+ICmK9 vVhvsHBSTdF9YM1in9ZXnF1LRkVUUS/HCOWnuKQYaICbc/siXVczgAbe6OVS+8JAN7Yt XU/ZvwM6aLeg9+pxhTiv2qDbn4o/hncWNeJ2ahjuFI5Gx/dSW08Uf2qa+ngHEjcZUv26 vfMg== X-Google-Smtp-Source: ANB0VdZAj+z283HOInNN1MV+JK6u0utwXRYvvGx8Aw8Q2aEzyrsjhmI3Tba1dIU8N5FBRzFOGzVoOA== X-Received: by 2002:a65:4043:: with SMTP id h3-v6mr30193789pgp.207.1536705313427; Tue, 11 Sep 2018 15:35:13 -0700 (PDT) Received: from vader.thefacebook.com ([2620:10d:c090:200::7:13b4]) by smtp.gmail.com with ESMTPSA id 186-v6sm18710176pgg.56.2018.09.11.15.35.12 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 11 Sep 2018 15:35:12 -0700 (PDT) From: Omar Sandoval To: linux-btrfs@vger.kernel.org Cc: kernel-team@fb.com, linux-mm@kvack.org Subject: [PATCH v7 1/6] mm: split SWP_FILE into SWP_ACTIVATED and SWP_FS Date: Tue, 11 Sep 2018 15:34:44 -0700 Message-Id: <6d63d8668c4287a4f6d203d65696e96f80abdfc7.1536704650.git.osandov@fb.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: References: 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: X-Virus-Scanned: ClamAV using ClamSMTP From: Omar Sandoval The SWP_FILE flag serves two purposes: to make swap_{read,write}page() go through the filesystem, and to make swapoff() call ->swap_deactivate(). For Btrfs, we want the latter but not the former, so split this flag into two. This makes us always call ->swap_deactivate() if ->swap_activate() succeeded, not just if it didn't add any swap extents itself. This also resolves the issue of the very misleading name of SWP_FILE, which is only used for swap files over NFS. Reviewed-by: Nikolay Borisov Signed-off-by: Omar Sandoval Acked-by: Andrew Morton --- include/linux/swap.h | 13 +++++++------ mm/page_io.c | 6 +++--- mm/swapfile.c | 13 ++++++++----- 3 files changed, 18 insertions(+), 14 deletions(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index 8e2c11e692ba..0fda0aa743f0 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -167,13 +167,14 @@ enum { SWP_SOLIDSTATE = (1 << 4), /* blkdev seeks are cheap */ SWP_CONTINUED = (1 << 5), /* swap_map has count continuation */ SWP_BLKDEV = (1 << 6), /* its a block device */ - SWP_FILE = (1 << 7), /* set after swap_activate success */ - SWP_AREA_DISCARD = (1 << 8), /* single-time swap area discards */ - SWP_PAGE_DISCARD = (1 << 9), /* freed swap page-cluster discards */ - SWP_STABLE_WRITES = (1 << 10), /* no overwrite PG_writeback pages */ - SWP_SYNCHRONOUS_IO = (1 << 11), /* synchronous IO is efficient */ + SWP_ACTIVATED = (1 << 7), /* set after swap_activate success */ + SWP_FS = (1 << 8), /* swap file goes through fs */ + SWP_AREA_DISCARD = (1 << 9), /* single-time swap area discards */ + SWP_PAGE_DISCARD = (1 << 10), /* freed swap page-cluster discards */ + SWP_STABLE_WRITES = (1 << 11), /* no overwrite PG_writeback pages */ + SWP_SYNCHRONOUS_IO = (1 << 12), /* synchronous IO is efficient */ /* add others here before... */ - SWP_SCANNING = (1 << 12), /* refcount in scan_swap_map */ + SWP_SCANNING = (1 << 13), /* refcount in scan_swap_map */ }; #define SWAP_CLUSTER_MAX 32UL diff --git a/mm/page_io.c b/mm/page_io.c index aafd19ec1db4..e8653c368069 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -283,7 +283,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc, struct swap_info_struct *sis = page_swap_info(page); VM_BUG_ON_PAGE(!PageSwapCache(page), page); - if (sis->flags & SWP_FILE) { + if (sis->flags & SWP_FS) { struct kiocb kiocb; struct file *swap_file = sis->swap_file; struct address_space *mapping = swap_file->f_mapping; @@ -365,7 +365,7 @@ int swap_readpage(struct page *page, bool synchronous) goto out; } - if (sis->flags & SWP_FILE) { + if (sis->flags & SWP_FS) { struct file *swap_file = sis->swap_file; struct address_space *mapping = swap_file->f_mapping; @@ -423,7 +423,7 @@ int swap_set_page_dirty(struct page *page) { struct swap_info_struct *sis = page_swap_info(page); - if (sis->flags & SWP_FILE) { + if (sis->flags & SWP_FS) { struct address_space *mapping = sis->swap_file->f_mapping; VM_BUG_ON_PAGE(!PageSwapCache(page), page); diff --git a/mm/swapfile.c b/mm/swapfile.c index d954b71c4f9c..d3f95833d12e 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -989,7 +989,7 @@ int get_swap_pages(int n_goal, swp_entry_t swp_entries[], int entry_size) goto nextsi; } if (size == SWAPFILE_CLUSTER) { - if (!(si->flags & SWP_FILE)) + if (!(si->flags & SWP_FS)) n_ret = swap_alloc_cluster(si, swp_entries); } else n_ret = scan_swap_map_slots(si, SWAP_HAS_CACHE, @@ -2310,12 +2310,13 @@ static void destroy_swap_extents(struct swap_info_struct *sis) kfree(se); } - if (sis->flags & SWP_FILE) { + if (sis->flags & SWP_ACTIVATED) { struct file *swap_file = sis->swap_file; struct address_space *mapping = swap_file->f_mapping; - sis->flags &= ~SWP_FILE; - mapping->a_ops->swap_deactivate(swap_file); + sis->flags &= ~SWP_ACTIVATED; + if (mapping->a_ops->swap_deactivate) + mapping->a_ops->swap_deactivate(swap_file); } } @@ -2411,8 +2412,10 @@ static int setup_swap_extents(struct swap_info_struct *sis, sector_t *span) if (mapping->a_ops->swap_activate) { ret = mapping->a_ops->swap_activate(sis, swap_file, span); + if (ret >= 0) + sis->flags |= SWP_ACTIVATED; if (!ret) { - sis->flags |= SWP_FILE; + sis->flags |= SWP_FS; ret = add_swap_extent(sis, 0, sis->max, 0); *span = sis->pages; }