From nobody Mon Jun 15 12:48:02 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0874AC433FE for ; Fri, 29 Apr 2022 00:44:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352891AbiD2AsE (ORCPT ); Thu, 28 Apr 2022 20:48:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237629AbiD2AsC (ORCPT ); Thu, 28 Apr 2022 20:48:02 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3350FBB902; Thu, 28 Apr 2022 17:44:46 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id BCA8121872; Fri, 29 Apr 2022 00:44:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1651193084; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JrU/wsC8sdfT/R0JtZvwzkc1EUgEvszFC5tR6hfJPHE=; b=HcAEspUL3B+9CGfESTkkWyVHLwjkJyuXcPrNSc2itnNpsG4afpKgD2fceNteEvGeIDzDkF vam2Q7ZjD4Gu5lf4cLuh8wj+2UI/XuhK0NK7Izl6oYOI2DyEklQM6ZBCinCG9RVEBqv6mY w/P+5PydmAsMkqnfWIlJG5nPcjgdwrc= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1651193084; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JrU/wsC8sdfT/R0JtZvwzkc1EUgEvszFC5tR6hfJPHE=; b=pAN5MwCEnPu7JYa0cLy1RgMWnMu44JE2gGqZNmMinRWucAubigJnhLMMABEnAgm3z3Cafp P+EvQ9EmCJq+XnAQ== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id A593513491; Fri, 29 Apr 2022 00:44:42 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id ljwOGfo0a2IrSgAAMHmgww (envelope-from ); Fri, 29 Apr 2022 00:44:42 +0000 Subject: [PATCH 1/2] MM: handle THP in swap_*page_fs() From: NeilBrown To: Andrew Morton Cc: Geert Uytterhoeven , Christoph Hellwig , Miaohe Lin , linux-nfs@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Fri, 29 Apr 2022 10:43:34 +1000 Message-ID: <165119301488.15698.9457662928942765453.stgit@noble.brown> In-Reply-To: <165119280115.15698.2629172320052218921.stgit@noble.brown> References: <165119280115.15698.2629172320052218921.stgit@noble.brown> User-Agent: StGit/1.5 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Pages passed to swap_readpage()/swap_writepage() are not necessarily all the same size - there may be transparent-huge-pages involves. The BIO paths of swap_*page() handle this correctly, but the SWP_FS_OPS path does not. So we need to use thp_size() to find the size, not just assume PAGE_SIZE, and we need to track the total length of the request, not just assume it is "page * PAGE_SIZE". Reported-by: Miaohe Lin Signed-off-by: NeilBrown --- mm/page_io.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/mm/page_io.c b/mm/page_io.c index c132511f521c..d636a3531cad 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -239,6 +239,7 @@ struct swap_iocb { struct kiocb iocb; struct bio_vec bvec[SWAP_CLUSTER_MAX]; int pages; + int len; }; static mempool_t *sio_pool; =20 @@ -261,7 +262,7 @@ static void sio_write_complete(struct kiocb *iocb, long= ret) struct page *page =3D sio->bvec[0].bv_page; int p; =20 - if (ret !=3D PAGE_SIZE * sio->pages) { + if (ret !=3D sio->len) { /* * In the case of swap-over-nfs, this can be a * temporary failure if the system has limited @@ -301,7 +302,7 @@ static int swap_writepage_fs(struct page *page, struct = writeback_control *wbc) sio =3D *wbc->swap_plug; if (sio) { if (sio->iocb.ki_filp !=3D swap_file || - sio->iocb.ki_pos + sio->pages * PAGE_SIZE !=3D pos) { + sio->iocb.ki_pos + sio->len !=3D pos) { swap_write_unplug(sio); sio =3D NULL; } @@ -312,10 +313,12 @@ static int swap_writepage_fs(struct page *page, struc= t writeback_control *wbc) sio->iocb.ki_complete =3D sio_write_complete; sio->iocb.ki_pos =3D pos; sio->pages =3D 0; + sio->len =3D 0; } sio->bvec[sio->pages].bv_page =3D page; - sio->bvec[sio->pages].bv_len =3D PAGE_SIZE; + sio->bvec[sio->pages].bv_len =3D thp_size(page); sio->bvec[sio->pages].bv_offset =3D 0; + sio->len +=3D thp_size(page); sio->pages +=3D 1; if (sio->pages =3D=3D ARRAY_SIZE(sio->bvec) || !wbc->swap_plug) { swap_write_unplug(sio); @@ -371,8 +374,7 @@ void swap_write_unplug(struct swap_iocb *sio) struct address_space *mapping =3D sio->iocb.ki_filp->f_mapping; int ret; =20 - iov_iter_bvec(&from, WRITE, sio->bvec, sio->pages, - PAGE_SIZE * sio->pages); + iov_iter_bvec(&from, WRITE, sio->bvec, sio->pages, sio->len); ret =3D mapping->a_ops->swap_rw(&sio->iocb, &from); if (ret !=3D -EIOCBQUEUED) sio_write_complete(&sio->iocb, ret); @@ -383,7 +385,7 @@ static void sio_read_complete(struct kiocb *iocb, long = ret) struct swap_iocb *sio =3D container_of(iocb, struct swap_iocb, iocb); int p; =20 - if (ret =3D=3D PAGE_SIZE * sio->pages) { + if (ret =3D=3D sio->len) { for (p =3D 0; p < sio->pages; p++) { struct page *page =3D sio->bvec[p].bv_page; =20 @@ -415,7 +417,7 @@ static void swap_readpage_fs(struct page *page, sio =3D *plug; if (sio) { if (sio->iocb.ki_filp !=3D sis->swap_file || - sio->iocb.ki_pos + sio->pages * PAGE_SIZE !=3D pos) { + sio->iocb.ki_pos + sio->len !=3D pos) { swap_read_unplug(sio); sio =3D NULL; } @@ -426,10 +428,12 @@ static void swap_readpage_fs(struct page *page, sio->iocb.ki_pos =3D pos; sio->iocb.ki_complete =3D sio_read_complete; sio->pages =3D 0; + sio->len =3D 0; } sio->bvec[sio->pages].bv_page =3D page; - sio->bvec[sio->pages].bv_len =3D PAGE_SIZE; + sio->bvec[sio->pages].bv_len =3D thp_size(page); sio->bvec[sio->pages].bv_offset =3D 0; + sio->len +=3D thp_size(page); sio->pages +=3D 1; if (sio->pages =3D=3D ARRAY_SIZE(sio->bvec) || !plug) { swap_read_unplug(sio); @@ -521,8 +525,7 @@ void __swap_read_unplug(struct swap_iocb *sio) struct address_space *mapping =3D sio->iocb.ki_filp->f_mapping; int ret; =20 - iov_iter_bvec(&from, READ, sio->bvec, sio->pages, - PAGE_SIZE * sio->pages); + iov_iter_bvec(&from, READ, sio->bvec, sio->pages, sio->len); ret =3D mapping->a_ops->swap_rw(&sio->iocb, &from); if (ret !=3D -EIOCBQUEUED) sio_read_complete(&sio->iocb, ret); From nobody Mon Jun 15 12:48:02 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C63B7C433FE for ; Fri, 29 Apr 2022 00:44:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353013AbiD2AsK (ORCPT ); Thu, 28 Apr 2022 20:48:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237629AbiD2AsJ (ORCPT ); Thu, 28 Apr 2022 20:48:09 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3596BB902; 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t=1651193091; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iDTLraYqnWApa1mXlMLLgzsQSZO/JsdcUgftlr7aovM=; b=1wMQN6a64l7rZ/v4UXE8U90xh7OGxjydYxyu1kmSUBId/NHpwcPt6Mw4IPLABKipjSx/M9 35I2hF4rrmhDshCA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 9A17E13491; Fri, 29 Apr 2022 00:44:49 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id blhJFgE1a2IzSgAAMHmgww (envelope-from ); Fri, 29 Apr 2022 00:44:49 +0000 Subject: [PATCH 2/2] NFS: rename nfs_direct_IO and use as ->swap_rw From: NeilBrown To: Andrew Morton Cc: Geert Uytterhoeven , Christoph Hellwig , Miaohe Lin , linux-nfs@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Fri, 29 Apr 2022 10:43:34 +1000 Message-ID: <165119301493.15698.7491285551903597618.stgit@noble.brown> In-Reply-To: <165119280115.15698.2629172320052218921.stgit@noble.brown> References: <165119280115.15698.2629172320052218921.stgit@noble.brown> User-Agent: StGit/1.5 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The nfs_direct_IO() exists to support SWAP IO, but hasn't worked for a while. We now need a ->swap_rw function which behaves slightly differently, returning zero for success rather than a byte count. So modify nfs_direct_IO accordingly, rename it, and use it as the ->swap_rw function. Tested-by: Geert Uytterhoeven (on Renesas RSK+RZA= 1 with 32 MiB of SDRAM) Reviewed-by: Christoph Hellwig Signed-off-by: NeilBrown --- fs/nfs/direct.c | 23 ++++++++++------------- fs/nfs/file.c | 5 +---- include/linux/nfs_fs.h | 2 +- 3 files changed, 12 insertions(+), 18 deletions(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 11c566d8769f..4eb2a8380a28 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -153,28 +153,25 @@ nfs_direct_count_bytes(struct nfs_direct_req *dreq, } =20 /** - * nfs_direct_IO - NFS address space operation for direct I/O + * nfs_swap_rw - NFS address space operation for swap I/O * @iocb: target I/O control block * @iter: I/O buffer * - * The presence of this routine in the address space ops vector means - * the NFS client supports direct I/O. However, for most direct IO, we - * shunt off direct read and write requests before the VFS gets them, - * so this method is only ever called for swap. + * Perform IO to the swap-file. This is much like direct IO. */ -ssize_t nfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) +int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter) { - struct inode *inode =3D iocb->ki_filp->f_mapping->host; - - /* we only support swap file calling nfs_direct_IO */ - if (!IS_SWAPFILE(inode)) - return 0; + ssize_t ret; =20 VM_BUG_ON(iov_iter_count(iter) !=3D PAGE_SIZE); =20 if (iov_iter_rw(iter) =3D=3D READ) - return nfs_file_direct_read(iocb, iter, true); - return nfs_file_direct_write(iocb, iter, true); + ret =3D nfs_file_direct_read(iocb, iter, true); + else + ret =3D nfs_file_direct_write(iocb, iter, true); + if (ret < 0) + return ret; + return 0; } =20 static void nfs_direct_release_pages(struct page **pages, unsigned int npa= ges) diff --git a/fs/nfs/file.c b/fs/nfs/file.c index e1d10a3e086a..bfb4b707b07e 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -490,10 +490,6 @@ static int nfs_swap_activate(struct swap_info_struct *= sis, struct file *file, struct rpc_clnt *clnt =3D NFS_CLIENT(inode); struct nfs_client *cl =3D NFS_SERVER(inode)->nfs_client; =20 - if (!file->f_mapping->a_ops->swap_rw) - /* Cannot support swap */ - return -EINVAL; - spin_lock(&inode->i_lock); blocks =3D inode->i_blocks; isize =3D inode->i_size; @@ -550,6 +546,7 @@ const struct address_space_operations nfs_file_aops =3D= { .error_remove_page =3D generic_error_remove_page, .swap_activate =3D nfs_swap_activate, .swap_deactivate =3D nfs_swap_deactivate, + .swap_rw =3D nfs_swap_rw, }; =20 /* diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index b48b9259e02c..fd5543486a3f 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -507,7 +507,7 @@ static inline const struct cred *nfs_file_cred(struct f= ile *file) /* * linux/fs/nfs/direct.c */ -extern ssize_t nfs_direct_IO(struct kiocb *, struct iov_iter *); +int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter); ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter, bool swap); ssize_t nfs_file_direct_write(struct kiocb *iocb,