From patchwork Tue Nov 10 03:36:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 11893131 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 DCDEA697 for ; Tue, 10 Nov 2020 03:38:30 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6FFA02080A for ; Tue, 10 Nov 2020 03:37:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="U3q0RUWv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6FFA02080A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BDD926B0078; Mon, 9 Nov 2020 22:37:14 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id B6B726B0073; Mon, 9 Nov 2020 22:37:14 -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 9BCCA6B0078; Mon, 9 Nov 2020 22:37:14 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0125.hostedemail.com [216.40.44.125]) by kanga.kvack.org (Postfix) with ESMTP id 55F566B0073 for ; Mon, 9 Nov 2020 22:37:14 -0500 (EST) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id ED02F181AEF1A for ; Tue, 10 Nov 2020 03:37:13 +0000 (UTC) X-FDA: 77467097946.02.pest56_260985b272f1 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id C969510097AA0 for ; Tue, 10 Nov 2020 03:37:13 +0000 (UTC) X-Spam-Summary: 1,0,0,e8c589097fe27e79,d41d8cd98f00b204,willy@infradead.org,,RULES_HIT:41:69:355:379:541:800:960:973:988:989:1260:1311:1314:1345:1359:1437:1515:1535:1544:1605:1711:1730:1747:1777:1792:1981:2194:2199:2393:2553:2559:2562:2693:2914:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3872:4321:4605:5007:6261:6653:7514:7903:8660:8957:9592:10004:10946:11026:11473:11658:11914:12043:12291:12296:12297:12438:12555:12679:12683:12895:12986:13148:13161:13229:13230:13894:14096:14110:14181:14394:14721:21080:21212:21451:21627:21939:21990:30054:30070:30090,0,RBL:90.155.50.34:@infradead.org:.lbl8.mailshell.net-62.8.15.100 64.201.201.201;04yfu69tdbpmxid91w5qen3eoasmdyc8why616oxnuj8u7yt8n9fybfjbcprpr7.fkzuh1thwfq81gs11tfxa3i73pwrrqy9ji6rr3c1a6gupfn18oodjf7jhigafmw.h-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:70,LUA_SUMMARY:none X-HE-Tag: pest56_260985b272f1 X-Filterd-Recvd-Size: 5914 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf33.hostedemail.com (Postfix) with ESMTP for ; Tue, 10 Nov 2020 03:37:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=5LafMIUog0t1R4fvpnZSdZTQ3XRYlwYMfxi8ZQP6OkA=; b=U3q0RUWv1xPD2RzLqRiAwTQG7s DA2C2TggH9C82kwAOYFMHgvQYL179PG/hpPBCtixJp2G6LB818K/7e0RbFHhb/LWwIsn39f6xQk0+ YJpElvNzTfp5vpHPVjJLESk+0WnQvbf41DaIjVYoUiCYwCw3ubR2vjfWNyAcdYzD0w7TSQOM0+Ny/ IQPYQXbUhcYiOqdmgjWKDja3xOg9hxahNwYMrjftjq3G8T0vFE999yluQHmOFroPLyMh81yMSs7sm EZcTN7SjChwvC8ufnCmmJxAR1eQw3tuUTvvLDjG5jdGSKxb0PrJ1uXMh3ZWWbv5SwRp3odlqYCDRv i1fM0GPA==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kcKT0-00065Y-9k; Tue, 10 Nov 2020 03:37:10 +0000 From: "Matthew Wilcox (Oracle)" To: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Cc: "Matthew Wilcox (Oracle)" , hch@lst.de, kent.overstreet@gmail.com Subject: [PATCH v3 09/18] mm/filemap: Change filemap_read_page calling conventions Date: Tue, 10 Nov 2020 03:36:54 +0000 Message-Id: <20201110033703.23261-10-willy@infradead.org> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20201110033703.23261-1-willy@infradead.org> References: <20201110033703.23261-1-willy@infradead.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: Make this function more generic by passing the file instead of the iocb. Check in the callers whether we should call readpage or not. Also make it return an errno / 0 / AOP_TRUNCATED_PAGE, and make calling put_page() the caller's responsibility. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Kent Overstreet --- mm/filemap.c | 89 +++++++++++++++++++++++++--------------------------- 1 file changed, 42 insertions(+), 47 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 3e2994a84a81..52d606916477 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2197,56 +2197,38 @@ static void filemap_get_read_batch(struct address_space *mapping, rcu_read_unlock(); } -static struct page *filemap_read_page(struct kiocb *iocb, struct file *filp, - struct address_space *mapping, struct page *page) +static int filemap_read_page(struct file *file, struct address_space *mapping, + struct page *page) { - struct file_ra_state *ra = &filp->f_ra; int error; - if (iocb->ki_flags & (IOCB_NOIO | IOCB_NOWAIT | IOCB_WAITQ)) { - unlock_page(page); - put_page(page); - return ERR_PTR(-EAGAIN); - } - /* - * A previous I/O error may have been due to temporary - * failures, eg. multipath errors. - * PG_error will be set again if readpage fails. + * A previous I/O error may have been due to temporary failures, + * eg. multipath errors. PG_error will be set again if readpage + * fails. */ ClearPageError(page); /* Start the actual read. The read will unlock the page. */ - error = mapping->a_ops->readpage(filp, page); - - if (unlikely(error)) { - put_page(page); - return error != AOP_TRUNCATED_PAGE ? ERR_PTR(error) : NULL; - } + error = mapping->a_ops->readpage(file, page); + if (error) + return error; + if (PageUptodate(page)) + return 0; + error = lock_page_killable(page); + if (error) + return error; if (!PageUptodate(page)) { - error = lock_page_killable(page); - if (unlikely(error)) { - put_page(page); - return ERR_PTR(error); - } - if (!PageUptodate(page)) { - if (page->mapping == NULL) { - /* - * invalidate_mapping_pages got it - */ - unlock_page(page); - put_page(page); - return NULL; - } - unlock_page(page); - shrink_readahead_size_eio(ra); - put_page(page); - return ERR_PTR(-EIO); + if (page->mapping == NULL) { + /* page truncated */ + error = AOP_TRUNCATED_PAGE; + } else { + shrink_readahead_size_eio(&file->f_ra); + error = -EIO; } - unlock_page(page); } - - return page; + unlock_page(page); + return error; } static struct page *filemap_update_page(struct kiocb *iocb, struct file *filp, @@ -2288,7 +2270,18 @@ static struct page *filemap_update_page(struct kiocb *iocb, struct file *filp, return page; readpage: - return filemap_read_page(iocb, filp, mapping, page); + if (iocb->ki_flags & (IOCB_NOIO | IOCB_NOWAIT | IOCB_WAITQ)) { + unlock_page(page); + put_page(page); + return ERR_PTR(-EAGAIN); + } + error = filemap_read_page(iocb->ki_filp, mapping, page); + if (!error) + return page; + put_page(page); + if (error == AOP_TRUNCATED_PAGE) + return NULL; + return ERR_PTR(error); truncated: unlock_page(page); put_page(page); @@ -2304,7 +2297,7 @@ static struct page *filemap_create_page(struct kiocb *iocb, struct page *page; int error; - if (iocb->ki_flags & IOCB_NOIO) + if (iocb->ki_flags & (IOCB_NOIO | IOCB_NOWAIT | IOCB_WAITQ)) return ERR_PTR(-EAGAIN); page = page_cache_alloc(mapping); @@ -2313,12 +2306,14 @@ static struct page *filemap_create_page(struct kiocb *iocb, error = add_to_page_cache_lru(page, mapping, index, mapping_gfp_constraint(mapping, GFP_KERNEL)); - if (error) { - put_page(page); - return error != -EEXIST ? ERR_PTR(error) : NULL; - } - - return filemap_read_page(iocb, filp, mapping, page); + if (!error) + error = filemap_read_page(iocb->ki_filp, mapping, page); + if (!error) + return page; + put_page(page); + if (error == -EEXIST || error == AOP_TRUNCATED_PAGE) + return NULL; + return ERR_PTR(error); } static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,