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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 DBE65C83004 for ; Wed, 29 Apr 2020 14:04:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD69D208FE for ; Wed, 29 Apr 2020 14:04:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=android.com header.i=@android.com header.b="ITfmWJKK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728007AbgD2ODw (ORCPT ); Wed, 29 Apr 2020 10:03:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728080AbgD2ODw (ORCPT ); Wed, 29 Apr 2020 10:03:52 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ACE60C03C1AD for ; Wed, 29 Apr 2020 07:03:51 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id x17so2683965wrt.5 for ; Wed, 29 Apr 2020 07:03:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=android.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=PoJQjkbDBTvS6CFNLYXBcb580Ir6qHsMYFIGsSVt/dk=; b=ITfmWJKKpQF4vwJQgg3vHBkXHE0SUBFXOnZzX6K2D+4GdAQYvyJzC5trVgkBo+K47+ TIcQX1Z+K/C5s1TNPsk/8WPZBxGpRyuS2Ol79xxwdA/FObD3HukuPGqH+1DFB/DKMKF4 Qyw8YmKJpXwYH/TcFDtiPJzVccGPqBKDesdZ1vZIAKPNiL4FJ/Atzo50cdCUIOoRprO7 mKcoWEvW7NWEjdmKfZJkoevt82+TbbWRIMvuW0Xux+Tf3LV3L5jTUmJ8AfHIqCC1zDC/ RfULXfIBWninskSu0MfXNW2zhxdSpn1oigOJF420HWBBoWfnOr/9hWeV2b7Sjc1geqBW Fb5g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=PoJQjkbDBTvS6CFNLYXBcb580Ir6qHsMYFIGsSVt/dk=; b=ohFtu0Bw2oftE1mb0WWWGxoSoxFQBE5FFj8nGUE4p0WDcn1duXvjzaON26p03oo76r 8s+z9VjISxTNdCyBrDhHzCGM9BPv6K5Z9hc17mcMWAxhHeIBb75RZCyQO/+qvLTg+Faw 3jh9cDrjpuw5xMCBy29x5viQKzS95icosdIXIQIOgtsrLq4k4vhlDwScVS58l+bSLIxg N6mdD2CkkNsgFgVDQwD+apDevS6bNlOwsy5/tQm3+O7dqFMDTYkBZ6Ml+sbCuexs0YPV uRNwrE6kv3gI3hEKily5pI4Rt6XzM18qrKKA/vygYXIX1KnVEoL98+gqYsPBMFxR8GSe L8SA== X-Gm-Message-State: AGi0PubhBjXwc98/0N/vYe2sl8UAWrc68O8XRchuXgC12FmdJwaN0GEv ItNQOWfKt4BvtFbBUvrNQ2bJQg== X-Google-Smtp-Source: APiQypLdGhK29pFXm0dZ/bi2Kip6HNq6NAOpBoOKsa7X/fOmZscDthU9nK3s9w7zqMH2en3DTmnWNA== X-Received: by 2002:adf:e84f:: with SMTP id d15mr41411225wrn.296.1588169030446; Wed, 29 Apr 2020 07:03:50 -0700 (PDT) Received: from maco2.ams.corp.google.com (a83-162-234-235.adsl.xs4all.nl. [83.162.234.235]) by smtp.gmail.com with ESMTPSA id d133sm8887008wmc.27.2020.04.29.07.03.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Apr 2020 07:03:49 -0700 (PDT) From: Martijn Coenen To: axboe@kernel.dk, hch@lst.de, ming.lei@redhat.com Cc: narayan@google.com, zezeozue@google.com, kernel-team@android.com, maco@google.com, bvanassche@acm.org, Chaitanya.Kulkarni@wdc.com, jaegeuk@kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Martijn Coenen Subject: [PATCH v4 04/10] loop: Refactor loop_set_status() size calculation Date: Wed, 29 Apr 2020 16:03:35 +0200 Message-Id: <20200429140341.13294-5-maco@android.com> X-Mailer: git-send-email 2.26.2.303.gf8c07b1a785-goog In-Reply-To: <20200429140341.13294-1-maco@android.com> References: <20200429140341.13294-1-maco@android.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org figure_loop_size() calculates the loop size based on the passed in parameters, but at the same time it updates the offset and sizelimit parameters in the loop device configuration. That is a somewhat unexpected side effect of a function with this name, and it is only only needed by one of the two callers of this function - loop_set_status(). Move the lo_offset and lo_sizelimit assignment back into loop_set_status(), and use the newly factored out functions to validate and apply the newly calculated size. This allows us to get rid of figure_loop_size() in a follow-up commit. Signed-off-by: Martijn Coenen --- drivers/block/loop.c | 44 +++++++++++++++++++++++--------------------- 1 file changed, 23 insertions(+), 21 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 8f3194c2b8aa..9f5913879921 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -268,11 +268,6 @@ figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit) if (err) return err; - if (lo->lo_offset != offset) - lo->lo_offset = offset; - if (lo->lo_sizelimit != sizelimit) - lo->lo_sizelimit = sizelimit; - loop_set_size(lo, size); return 0; @@ -1294,6 +1289,8 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) kuid_t uid = current_uid(); struct block_device *bdev; bool partscan = false; + bool size_changed = false; + loff_t validated_size; err = mutex_lock_killable(&loop_ctl_mutex); if (err) @@ -1315,6 +1312,13 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) if (lo->lo_offset != info->lo_offset || lo->lo_sizelimit != info->lo_sizelimit) { + loff_t size = get_size(info->lo_offset, info->lo_sizelimit, + lo->lo_backing_file); + err = loop_validate_size(size); + if (err) + goto out_unlock; + size_changed = true; + validated_size = size; sync_blockdev(lo->lo_device); kill_bdev(lo->lo_device); } @@ -1322,6 +1326,15 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) /* I/O need to be drained during transfer transition */ blk_mq_freeze_queue(lo->lo_queue); + if (size_changed && lo->lo_device->bd_inode->i_mapping->nrpages) { + /* If any pages were dirtied after kill_bdev(), try again */ + err = -EAGAIN; + pr_warn("%s: loop%d (%s) has still dirty pages (nrpages=%lu)\n", + __func__, lo->lo_number, lo->lo_file_name, + lo->lo_device->bd_inode->i_mapping->nrpages); + goto out_unfreeze; + } + err = loop_release_xfer(lo); if (err) goto out_unfreeze; @@ -1345,22 +1358,8 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) if (err) goto out_unfreeze; - if (lo->lo_offset != info->lo_offset || - lo->lo_sizelimit != info->lo_sizelimit) { - /* kill_bdev should have truncated all the pages */ - if (lo->lo_device->bd_inode->i_mapping->nrpages) { - err = -EAGAIN; - pr_warn("%s: loop%d (%s) has still dirty pages (nrpages=%lu)\n", - __func__, lo->lo_number, lo->lo_file_name, - lo->lo_device->bd_inode->i_mapping->nrpages); - goto out_unfreeze; - } - if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit)) { - err = -EFBIG; - goto out_unfreeze; - } - } - + lo->lo_offset = info->lo_offset; + lo->lo_sizelimit = info->lo_sizelimit; memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE); memcpy(lo->lo_crypt_name, info->lo_crypt_name, LO_NAME_SIZE); lo->lo_file_name[LO_NAME_SIZE-1] = 0; @@ -1384,6 +1383,9 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) lo->lo_key_owner = uid; } + if (size_changed) + loop_set_size(lo, validated_size); + loop_config_discard(lo); /* update dio if lo_offset or transfer is changed */ -- 2.26.2.303.gf8c07b1a785-goog