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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 D1D4EC2D0CA for ; Thu, 12 Dec 2019 19:01:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A34132073D for ; Thu, 12 Dec 2019 19:01:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="IckOWSwJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730632AbfLLTBq (ORCPT ); Thu, 12 Dec 2019 14:01:46 -0500 Received: from mail-io1-f68.google.com ([209.85.166.68]:38928 "EHLO mail-io1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730628AbfLLTBp (ORCPT ); Thu, 12 Dec 2019 14:01:45 -0500 Received: by mail-io1-f68.google.com with SMTP id c16so3936565ioh.6 for ; Thu, 12 Dec 2019 11:01:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=GaJCkgUv/B3OET1g1Gk3ujWzgIVpNM0nxRodwjfiGBE=; b=IckOWSwJdM1mRDe5xLg+1QZWh5GjmzKz/7oAhzljHbAQD3IR8KlQNignWa1viyT4en Bh37pENQzkkWfMCAI6BipdGMRo/FeyG1ZLUKPSdW+BN/fp8yr0o4MzfkgwtRhNsjRco+ M09XIHEM+8rPeoSpTB5EtkKznUCHqVeLvbg1q562VXLpYeQgoKspfnzL5cXCMwpaPm9s 64iPUDt8t+FhqGPPjCxwjQKb/UMTjRByOLC6AKfFpFvHPt5TTIbYK8wViTd7F3Hrs/jz F0x/5d299vyhYmAirrEFlRTDD/S4fijWr09sEYNA74raM3wwMiGwx+yKRv9O7TOmRyd4 3+OQ== 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=GaJCkgUv/B3OET1g1Gk3ujWzgIVpNM0nxRodwjfiGBE=; b=p8z2HrLlzWbQs5UaYJAcWLRu9OUfYHtv8sFPmgzeXPOSc6zxwo+WErFW78ZuMHkSoH r3XmeaokEh4QjqY9Ewooo7HTlQeCE9iWq5whY5ksqmbpGwFiifHX8y2/v3YwCr1HObZY H9U3ZKkPdXLwlAqYwmCG0wFH9zML0NFTwt4hc9U+TxYrulDe775WlIJy3C2BdPXdgYsN lqOOIVDR96MfggsroCQi/N5nFnecml0iKhMhyQPcIEGJRTYscdFiPEScYeR/igO9dNJm PUCQNSg0vNv9Tc5qxymEogFI9DKZvmXDXxWIsXy3sqkxcZM15eASXIhnTGktn1GDr7Qf FJeQ== X-Gm-Message-State: APjAAAUyHJ7XFs7WOJjMEsFHOkzfEpP3yUA9c1/xSxN8TJuRJhznHACp Ob+h8ilTQ9Mu8kCQDIaOAB46Pw== X-Google-Smtp-Source: APXvYqwjTIM6kPV9uE6Psr7sf1orKaXXnKqktbjIaUiI0LaIo8/4HAcLiFgn4bEKliYaVLewxqJuUQ== X-Received: by 2002:a02:a388:: with SMTP id y8mr9511471jak.70.1576177304566; Thu, 12 Dec 2019 11:01:44 -0800 (PST) Received: from x1.thefacebook.com ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id i22sm1957745ill.40.2019.12.12.11.01.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Dec 2019 11:01:43 -0800 (PST) From: Jens Axboe To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org Cc: willy@infradead.org, clm@fb.com, torvalds@linux-foundation.org, david@fromorbit.com, Jens Axboe Subject: [PATCH 5/5] iomap: support RWF_UNCACHED for buffered writes Date: Thu, 12 Dec 2019 12:01:33 -0700 Message-Id: <20191212190133.18473-6-axboe@kernel.dk> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191212190133.18473-1-axboe@kernel.dk> References: <20191212190133.18473-1-axboe@kernel.dk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This adds support for RWF_UNCACHED for file systems using iomap to perform buffered writes. We use the generic infrastructure for this, by tracking pages we created and calling write_drop_cached_pages() to issue writeback and prune those pages. Signed-off-by: Jens Axboe --- fs/iomap/apply.c | 24 ++++++++++++++++++++++++ fs/iomap/buffered-io.c | 23 +++++++++++++++++++---- include/linux/iomap.h | 5 +++++ 3 files changed, 48 insertions(+), 4 deletions(-) diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c index e76148db03b8..11b6812f7b37 100644 --- a/fs/iomap/apply.c +++ b/fs/iomap/apply.c @@ -92,5 +92,29 @@ iomap_apply(struct iomap_data *data, const struct iomap_ops *ops, data->flags, &iomap); } + if (written && (data->flags & IOMAP_UNCACHED)) { + struct address_space *mapping = data->inode->i_mapping; + + end = data->pos + written; + ret = filemap_write_and_wait_range(mapping, data->pos, end); + if (ret) + goto out; + + /* + * No pages were created for this range, we're done + */ + if (!(iomap.flags & IOMAP_F_PAGE_CREATE)) + goto out; + + /* + * Try to invalidate cache pages for the range we just wrote. + * We don't care if invalidation fails as the write has still + * worked and leaving clean uptodate pages in the page cache + * isn't a corruption vector for uncached IO. + */ + invalidate_inode_pages2_range(mapping, + data->pos >> PAGE_SHIFT, end >> PAGE_SHIFT); + } +out: return written ? written : ret; } diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 0a1a195ed1cc..df9d6002858e 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -659,6 +659,7 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags, struct page **pagep, struct iomap *iomap, struct iomap *srcmap) { const struct iomap_page_ops *page_ops = iomap->page_ops; + unsigned aop_flags; struct page *page; int status = 0; @@ -675,8 +676,11 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags, return status; } + aop_flags = AOP_FLAG_NOFS; + if (flags & IOMAP_UNCACHED) + aop_flags |= AOP_FLAG_UNCACHED; page = grab_cache_page_write_begin(inode->i_mapping, pos >> PAGE_SHIFT, - AOP_FLAG_NOFS); + aop_flags); if (!page) { status = -ENOMEM; goto out_no_page; @@ -818,6 +822,7 @@ iomap_write_actor(const struct iomap_data *data, struct iomap *iomap, { struct inode *inode = data->inode; struct iov_iter *i = data->priv; + unsigned flags = data->flags; loff_t length = data->len; loff_t pos = data->pos; long status = 0; @@ -851,10 +856,17 @@ iomap_write_actor(const struct iomap_data *data, struct iomap *iomap, break; } - status = iomap_write_begin(inode, pos, bytes, 0, &page, iomap, - srcmap); - if (unlikely(status)) +retry: + status = iomap_write_begin(inode, pos, bytes, flags, + &page, iomap, srcmap); + if (unlikely(status)) { + if (status == -ENOMEM && (flags & IOMAP_UNCACHED)) { + iomap->flags |= IOMAP_F_PAGE_CREATE; + flags &= ~IOMAP_UNCACHED; + goto retry; + } break; + } if (mapping_writably_mapped(inode->i_mapping)) flush_dcache_page(page); @@ -907,6 +919,9 @@ iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *iter, }; loff_t ret = 0, written = 0; + if (iocb->ki_flags & IOCB_UNCACHED) + data.flags |= IOMAP_UNCACHED; + while (iov_iter_count(iter)) { data.len = iov_iter_count(iter); ret = iomap_apply(&data, ops, iomap_write_actor); diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 30f40145a9e9..30bb248e1d0d 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -48,12 +48,16 @@ struct vm_fault; * * IOMAP_F_BUFFER_HEAD indicates that the file system requires the use of * buffer heads for this mapping. + * + * IOMAP_F_PAGE_CREATE indicates that pages had to be allocated to satisfy + * this operation. */ #define IOMAP_F_NEW 0x01 #define IOMAP_F_DIRTY 0x02 #define IOMAP_F_SHARED 0x04 #define IOMAP_F_MERGED 0x08 #define IOMAP_F_BUFFER_HEAD 0x10 +#define IOMAP_F_PAGE_CREATE 0x20 /* * Flags set by the core iomap code during operations: @@ -121,6 +125,7 @@ struct iomap_page_ops { #define IOMAP_FAULT (1 << 3) /* mapping for page fault */ #define IOMAP_DIRECT (1 << 4) /* direct I/O */ #define IOMAP_NOWAIT (1 << 5) /* do not block */ +#define IOMAP_UNCACHED (1 << 6) struct iomap_ops { /* -- 2.24.1