From patchwork Mon May 22 20:57:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13251125 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 28760C7EE2D for ; Mon, 22 May 2023 20:59:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235102AbjEVU65 (ORCPT ); Mon, 22 May 2023 16:58:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235101AbjEVU6r (ORCPT ); Mon, 22 May 2023 16:58:47 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28DCE9D for ; Mon, 22 May 2023 13:57:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684789078; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=oZIY9GTPXEPoSMZhe+ryqBhZXmHTyjPJq3hYdlaANCY=; b=fbh6PoAe0MBDsCCYiBJqvVxtfuIiWw0Jup49wtbQCOowQGH6zF0HeVnRZaxq8gGYP2FvbM LOQw+jPlR01YvKjesmAeRMTn0zgdRRGg6vrpUq4Pa9jLgQ4rsAeKx9z7nOwZAd1P7f7yDI 37Y2tqNsthXCXKzcCOqKPsMkSbqSA3M= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-580-uxNl4WjbMQmkgPs6MbWOuQ-1; Mon, 22 May 2023 16:57:53 -0400 X-MC-Unique: uxNl4WjbMQmkgPs6MbWOuQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3732F28EC104; Mon, 22 May 2023 20:57:52 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9B2D02166B25; Mon, 22 May 2023 20:57:49 +0000 (UTC) From: David Howells To: Jens Axboe , Al Viro , Christoph Hellwig Cc: David Howells , Matthew Wilcox , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, John Hubbard , Dave Chinner , Christoph Hellwig Subject: [PATCH v21 1/6] iomap: Don't get an reference on ZERO_PAGE for direct I/O block zeroing Date: Mon, 22 May 2023 21:57:39 +0100 Message-Id: <20230522205744.2825689-2-dhowells@redhat.com> In-Reply-To: <20230522205744.2825689-1-dhowells@redhat.com> References: <20230522205744.2825689-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org ZERO_PAGE can't go away, no need to hold an extra reference. Signed-off-by: David Howells Reviewed-by: David Hildenbrand Reviewed-by: John Hubbard Reviewed-by: Dave Chinner Reviewed-by: Christoph Hellwig cc: Al Viro cc: linux-fsdevel@vger.kernel.org Reviewed-by: Jan Kara Reviewed-by: Christian Brauner --- fs/iomap/direct-io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 019cc87d0fb3..66a9f10e3207 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -203,7 +203,7 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, bio->bi_private = dio; bio->bi_end_io = iomap_dio_bio_end_io; - get_page(page); + bio_set_flag(bio, BIO_NO_PAGE_REF); __bio_add_page(bio, page, len, 0); iomap_dio_submit_bio(iter, dio, bio, pos); } From patchwork Mon May 22 20:57:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13251124 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 5AC02C77B73 for ; Mon, 22 May 2023 20:58:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235207AbjEVU64 (ORCPT ); Mon, 22 May 2023 16:58:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234728AbjEVU6q (ORCPT ); Mon, 22 May 2023 16:58:46 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B025CC6 for ; Mon, 22 May 2023 13:58:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684789079; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=edStQDA/gh3f03KMzWRlpjb2e/gxKf5/7u3ht9bl6/4=; b=f03ZF8rHtp1uumre1QtCJlDs+snBbhU3y9gJtM7g3A+QWdKLLVVF29SrmwIJv9uvOnEg7x tYXFH4D+kDgSG6pK9zzlU7Ctl49T4Vw0eGCovkHoZMFXUJ5HGLk5oLq/2Lcmk2TOFczomO 7dxDH1ByXO9+Fy+1YBN4iOUPHm/DZyI= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-610-M04EVDuVNPuz6Y2LP-abug-1; Mon, 22 May 2023 16:57:56 -0400 X-MC-Unique: M04EVDuVNPuz6Y2LP-abug-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 82EB9185A78E; Mon, 22 May 2023 20:57:55 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0A1CB1121314; Mon, 22 May 2023 20:57:52 +0000 (UTC) From: David Howells To: Jens Axboe , Al Viro , Christoph Hellwig Cc: David Howells , Matthew Wilcox , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Hellwig , John Hubbard Subject: [PATCH v21 2/6] block: Fix bio_flagged() so that gcc can better optimise it Date: Mon, 22 May 2023 21:57:40 +0100 Message-Id: <20230522205744.2825689-3-dhowells@redhat.com> In-Reply-To: <20230522205744.2825689-1-dhowells@redhat.com> References: <20230522205744.2825689-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Fix bio_flagged() so that multiple instances of it, such as: if (bio_flagged(bio, BIO_PAGE_REFFED) || bio_flagged(bio, BIO_PAGE_PINNED)) can be combined by the gcc optimiser into a single test in assembly (arguably, this is a compiler optimisation issue[1]). The missed optimisation stems from bio_flagged() comparing the result of the bitwise-AND to zero. This results in an out-of-line bio_release_page() being compiled to something like: <+0>: mov 0x14(%rdi),%eax <+3>: test $0x1,%al <+5>: jne 0xffffffff816dac53 <+7>: test $0x2,%al <+9>: je 0xffffffff816dac5c <+11>: movzbl %sil,%esi <+15>: jmp 0xffffffff816daba1 <__bio_release_pages> <+20>: jmp 0xffffffff81d0b800 <__x86_return_thunk> However, the test is superfluous as the return type is bool. Removing it results in: <+0>: testb $0x3,0x14(%rdi) <+4>: je 0xffffffff816e4af4 <+6>: movzbl %sil,%esi <+10>: jmp 0xffffffff816dab7c <__bio_release_pages> <+15>: jmp 0xffffffff81d0b7c0 <__x86_return_thunk> instead. Also, the MOVZBL instruction looks unnecessary[2] - I think it's just 're-booling' the mark_dirty parameter. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: John Hubbard cc: Jens Axboe cc: linux-block@vger.kernel.org Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108370 [1] Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108371 [2] Link: https://lore.kernel.org/r/167391056756.2311931.356007731815807265.stgit@warthog.procyon.org.uk/ # v6 Reviewed-by: Jan Kara Reviewed-by: Christian Brauner --- include/linux/bio.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/bio.h b/include/linux/bio.h index b3e7529ff55e..7f53be035cf0 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -229,7 +229,7 @@ static inline void bio_cnt_set(struct bio *bio, unsigned int count) static inline bool bio_flagged(struct bio *bio, unsigned int bit) { - return (bio->bi_flags & (1U << bit)) != 0; + return bio->bi_flags & (1U << bit); } static inline void bio_set_flag(struct bio *bio, unsigned int bit) From patchwork Mon May 22 20:57:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13251126 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 A107BC77B73 for ; Mon, 22 May 2023 20:59:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235184AbjEVU7Z (ORCPT ); Mon, 22 May 2023 16:59:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235185AbjEVU7N (ORCPT ); Mon, 22 May 2023 16:59:13 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC9D2F4 for ; Mon, 22 May 2023 13:58:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684789084; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TuE+HSvYodh9xYXD2lD0nf71BaZqaWOFZeqfoTjFcWg=; b=gxTaESDXE+GhFg8x/2/jOKov3lPa2+O7oD/xghyNlhL3wDhm855KRv6FJdVfF8xX8BSwzY nz42y8cnJDIDMpqXc1l/fGEexVQrSumbNw1lb8sJRivrhu+u1uz1pa41l6pFSCl8RuTDTJ TTAQjDVSFwtfjXKYwjbNfmqJ3vLWv/s= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-193-4iF6x20XMxWuSAjOpQPW7g-1; Mon, 22 May 2023 16:57:59 -0400 X-MC-Unique: 4iF6x20XMxWuSAjOpQPW7g-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A847F1C0150C; Mon, 22 May 2023 20:57:58 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 38CE8C478DB; Mon, 22 May 2023 20:57:56 +0000 (UTC) From: David Howells To: Jens Axboe , Al Viro , Christoph Hellwig Cc: David Howells , Matthew Wilcox , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Hellwig , John Hubbard Subject: [PATCH v21 3/6] block: Replace BIO_NO_PAGE_REF with BIO_PAGE_REFFED with inverted logic Date: Mon, 22 May 2023 21:57:41 +0100 Message-Id: <20230522205744.2825689-4-dhowells@redhat.com> In-Reply-To: <20230522205744.2825689-1-dhowells@redhat.com> References: <20230522205744.2825689-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Christoph Hellwig Replace BIO_NO_PAGE_REF with a BIO_PAGE_REFFED flag that has the inverted meaning is only set when a page reference has been acquired that needs to be released by bio_release_pages(). Signed-off-by: Christoph Hellwig Signed-off-by: David Howells Reviewed-by: John Hubbard cc: Al Viro cc: Jens Axboe cc: Jan Kara cc: Matthew Wilcox cc: Logan Gunthorpe cc: linux-block@vger.kernel.org Reviewed-by: Jan Kara --- Notes: ver #8) - Split out from another patch [hch]. - Don't default to BIO_PAGE_REFFED [hch]. ver #5) - Split from patch that uses iov_iter_extract_pages(). block/bio.c | 2 +- block/blk-map.c | 1 + fs/direct-io.c | 2 ++ fs/iomap/direct-io.c | 1 - include/linux/bio.h | 2 +- include/linux/blk_types.h | 2 +- 6 files changed, 6 insertions(+), 4 deletions(-) diff --git a/block/bio.c b/block/bio.c index 043944fd46eb..8516adeaea26 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1191,7 +1191,6 @@ void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) bio->bi_io_vec = (struct bio_vec *)iter->bvec; bio->bi_iter.bi_bvec_done = iter->iov_offset; bio->bi_iter.bi_size = size; - bio_set_flag(bio, BIO_NO_PAGE_REF); bio_set_flag(bio, BIO_CLONED); } @@ -1336,6 +1335,7 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) return 0; } + bio_set_flag(bio, BIO_PAGE_REFFED); do { ret = __bio_iov_iter_get_pages(bio, iter); } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); diff --git a/block/blk-map.c b/block/blk-map.c index 04c55f1c492e..33d9f6e89ba6 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -282,6 +282,7 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter, if (blk_queue_pci_p2pdma(rq->q)) extraction_flags |= ITER_ALLOW_P2PDMA; + bio_set_flag(bio, BIO_PAGE_REFFED); while (iov_iter_count(iter)) { struct page **pages, *stack_pages[UIO_FASTIOV]; ssize_t bytes; diff --git a/fs/direct-io.c b/fs/direct-io.c index 0b380bb8a81e..ad20f3428bab 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -402,6 +402,8 @@ dio_bio_alloc(struct dio *dio, struct dio_submit *sdio, bio->bi_end_io = dio_bio_end_aio; else bio->bi_end_io = dio_bio_end_io; + /* for now require references for all pages */ + bio_set_flag(bio, BIO_PAGE_REFFED); sdio->bio = bio; sdio->logical_offset_in_bio = sdio->cur_page_fs_offset; } diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 66a9f10e3207..08873f0627dd 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -203,7 +203,6 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, bio->bi_private = dio; bio->bi_end_io = iomap_dio_bio_end_io; - bio_set_flag(bio, BIO_NO_PAGE_REF); __bio_add_page(bio, page, len, 0); iomap_dio_submit_bio(iter, dio, bio, pos); } diff --git a/include/linux/bio.h b/include/linux/bio.h index 7f53be035cf0..0922729acd26 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -488,7 +488,7 @@ void zero_fill_bio(struct bio *bio); static inline void bio_release_pages(struct bio *bio, bool mark_dirty) { - if (!bio_flagged(bio, BIO_NO_PAGE_REF)) + if (bio_flagged(bio, BIO_PAGE_REFFED)) __bio_release_pages(bio, mark_dirty); } diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 740afe80f297..dfd2c2cb909d 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -323,7 +323,7 @@ struct bio { * bio flags */ enum { - BIO_NO_PAGE_REF, /* don't put release vec pages */ + BIO_PAGE_REFFED, /* put pages in bio_release_pages() */ BIO_CLONED, /* doesn't own data */ BIO_BOUNCED, /* bio is a bounce bio */ BIO_QUIET, /* Make BIO Quiet */ From patchwork Mon May 22 20:57:42 2023 Content-Type: text/plain; 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Mon, 22 May 2023 20:58:02 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 83F4540CFD45; Mon, 22 May 2023 20:57:59 +0000 (UTC) From: David Howells To: Jens Axboe , Al Viro , Christoph Hellwig Cc: David Howells , Matthew Wilcox , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Hellwig , John Hubbard Subject: [PATCH v21 4/6] block: Add BIO_PAGE_PINNED and associated infrastructure Date: Mon, 22 May 2023 21:57:42 +0100 Message-Id: <20230522205744.2825689-5-dhowells@redhat.com> In-Reply-To: <20230522205744.2825689-1-dhowells@redhat.com> References: <20230522205744.2825689-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Add BIO_PAGE_PINNED to indicate that the pages in a bio are pinned (FOLL_PIN) and that the pin will need removing. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: John Hubbard cc: Al Viro cc: Jens Axboe cc: Jan Kara cc: Matthew Wilcox cc: Logan Gunthorpe cc: linux-block@vger.kernel.org Reviewed-by: Jan Kara --- Notes: ver #10) - Drop bio_set_cleanup_mode(), open coding it instead. ver #9) - Only consider pinning in bio_set_cleanup_mode(). Ref'ing pages in struct bio is going away. - page_put_unpin() is removed; call unpin_user_page() and put_page() directly. - Use bio_release_page() in __bio_release_pages(). - BIO_PAGE_PINNED and BIO_PAGE_REFFED can't both be set, so use if-else when testing both of them. ver #8) - Move the infrastructure to clean up pinned pages to this patch [hch]. - Put BIO_PAGE_PINNED before BIO_PAGE_REFFED as the latter should probably be removed at some point. FOLL_PIN can then be renumbered first. block/bio.c | 6 +++--- block/blk.h | 12 ++++++++++++ include/linux/bio.h | 3 ++- include/linux/blk_types.h | 1 + 4 files changed, 18 insertions(+), 4 deletions(-) diff --git a/block/bio.c b/block/bio.c index 8516adeaea26..17bd01ecde36 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1169,7 +1169,7 @@ void __bio_release_pages(struct bio *bio, bool mark_dirty) bio_for_each_segment_all(bvec, bio, iter_all) { if (mark_dirty && !PageCompound(bvec->bv_page)) set_page_dirty_lock(bvec->bv_page); - put_page(bvec->bv_page); + bio_release_page(bio, bvec->bv_page); } } EXPORT_SYMBOL_GPL(__bio_release_pages); @@ -1489,8 +1489,8 @@ void bio_set_pages_dirty(struct bio *bio) * the BIO and re-dirty the pages in process context. * * It is expected that bio_check_pages_dirty() will wholly own the BIO from - * here on. It will run one put_page() against each page and will run one - * bio_put() against the BIO. + * here on. It will unpin each page and will run one bio_put() against the + * BIO. */ static void bio_dirty_fn(struct work_struct *work); diff --git a/block/blk.h b/block/blk.h index 45547bcf1119..e1ded2ccb3ca 100644 --- a/block/blk.h +++ b/block/blk.h @@ -420,6 +420,18 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset, unsigned int max_sectors, bool *same_page); +/* + * Clean up a page appropriately, where the page may be pinned, may have a + * ref taken on it or neither. + */ +static inline void bio_release_page(struct bio *bio, struct page *page) +{ + if (bio_flagged(bio, BIO_PAGE_PINNED)) + unpin_user_page(page); + else if (bio_flagged(bio, BIO_PAGE_REFFED)) + put_page(page); +} + struct request_queue *blk_alloc_queue(int node_id); int disk_scan_partitions(struct gendisk *disk, fmode_t mode); diff --git a/include/linux/bio.h b/include/linux/bio.h index 0922729acd26..8588bcfbc6ef 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -488,7 +488,8 @@ void zero_fill_bio(struct bio *bio); static inline void bio_release_pages(struct bio *bio, bool mark_dirty) { - if (bio_flagged(bio, BIO_PAGE_REFFED)) + if (bio_flagged(bio, BIO_PAGE_REFFED) || + bio_flagged(bio, BIO_PAGE_PINNED)) __bio_release_pages(bio, mark_dirty); } diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index dfd2c2cb909d..8ef209e3aa96 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -323,6 +323,7 @@ struct bio { * bio flags */ enum { + BIO_PAGE_PINNED, /* Unpin pages in bio_release_pages() */ BIO_PAGE_REFFED, /* put pages in bio_release_pages() */ BIO_CLONED, /* doesn't own data */ BIO_BOUNCED, /* bio is a bounce bio */ From patchwork Mon May 22 20:57:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13251129 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 6CD80C77B73 for ; Mon, 22 May 2023 20:59:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235249AbjEVU7c (ORCPT ); Mon, 22 May 2023 16:59:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235263AbjEVU7U (ORCPT ); Mon, 22 May 2023 16:59:20 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 728BC130 for ; Mon, 22 May 2023 13:58:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684789091; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ehlvfIu1rrXcuy8/PZvsT00k//DN+ilG0RL3yAJWLmk=; b=fDhO8fAhBWVLJKHrkKPN9p4ZxiMH3402lZ/rlZIrXtDLGc5AnHQqbLp4Pq8u77Yr8F1Ftm dIiJfooPAd6ug1txbw5SsYw/iGPLVFa/xwdH+5z9Xp9NLf2vnfu9BdVNIA8Bt81FC13cli apaozsJlO/EAs+30Z72a3+whUzupUpY= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-314-MKSAMsAkP0a73wRCpRgbJQ-1; Mon, 22 May 2023 16:58:07 -0400 X-MC-Unique: MKSAMsAkP0a73wRCpRgbJQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 18D64800159; Mon, 22 May 2023 20:58:06 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id EECB5400DFF; Mon, 22 May 2023 20:58:02 +0000 (UTC) From: David Howells To: Jens Axboe , Al Viro , Christoph Hellwig Cc: David Howells , Matthew Wilcox , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Hellwig , John Hubbard Subject: [PATCH v21 5/6] block: Convert bio_iov_iter_get_pages to use iov_iter_extract_pages Date: Mon, 22 May 2023 21:57:43 +0100 Message-Id: <20230522205744.2825689-6-dhowells@redhat.com> In-Reply-To: <20230522205744.2825689-1-dhowells@redhat.com> References: <20230522205744.2825689-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This will pin pages or leave them unaltered rather than getting a ref on them as appropriate to the iterator. The pages need to be pinned for DIO rather than having refs taken on them to prevent VM copy-on-write from malfunctioning during a concurrent fork() (the result of the I/O could otherwise end up being affected by/visible to the child process). Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: John Hubbard cc: Al Viro cc: Jens Axboe cc: Jan Kara cc: Matthew Wilcox cc: Logan Gunthorpe cc: linux-block@vger.kernel.org Reviewed-by: Jan Kara --- Notes: ver #10) - Drop bio_set_cleanup_mode(), open coding it instead. ver #8) - Split the patch up a bit [hch]. - We should only be using pinned/non-pinned pages and not ref'd pages, so adjust the comments appropriately. ver #7) - Don't treat BIO_PAGE_REFFED/PINNED as being the same as FOLL_GET/PIN. ver #5) - Transcribe the FOLL_* flags returned by iov_iter_extract_pages() to BIO_* flags and got rid of bi_cleanup_mode. - Replaced BIO_NO_PAGE_REF to BIO_PAGE_REFFED in the preceding patch. block/bio.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/block/bio.c b/block/bio.c index 17bd01ecde36..798cc4cf3bd2 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1205,7 +1205,7 @@ static int bio_iov_add_page(struct bio *bio, struct page *page, } if (same_page) - put_page(page); + bio_release_page(bio, page); return 0; } @@ -1219,7 +1219,7 @@ static int bio_iov_add_zone_append_page(struct bio *bio, struct page *page, queue_max_zone_append_sectors(q), &same_page) != len) return -EINVAL; if (same_page) - put_page(page); + bio_release_page(bio, page); return 0; } @@ -1230,10 +1230,10 @@ static int bio_iov_add_zone_append_page(struct bio *bio, struct page *page, * @bio: bio to add pages to * @iter: iov iterator describing the region to be mapped * - * Pins pages from *iter and appends them to @bio's bvec array. The - * pages will have to be released using put_page() when done. - * For multi-segment *iter, this function only adds pages from the - * next non-empty segment of the iov iterator. + * Extracts pages from *iter and appends them to @bio's bvec array. The pages + * will have to be cleaned up in the way indicated by the BIO_PAGE_PINNED flag. + * For a multi-segment *iter, this function only adds pages from the next + * non-empty segment of the iov iterator. */ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) { @@ -1265,9 +1265,9 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) * result to ensure the bio's total size is correct. The remainder of * the iov data will be picked up in the next bio iteration. */ - size = iov_iter_get_pages(iter, pages, - UINT_MAX - bio->bi_iter.bi_size, - nr_pages, &offset, extraction_flags); + size = iov_iter_extract_pages(iter, &pages, + UINT_MAX - bio->bi_iter.bi_size, + nr_pages, extraction_flags, &offset); if (unlikely(size <= 0)) return size ? size : -EFAULT; @@ -1300,7 +1300,7 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) iov_iter_revert(iter, left); out: while (i < nr_pages) - put_page(pages[i++]); + bio_release_page(bio, pages[i++]); return ret; } @@ -1335,7 +1335,8 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) return 0; } - bio_set_flag(bio, BIO_PAGE_REFFED); + if (iov_iter_extract_will_pin(iter)) + bio_set_flag(bio, BIO_PAGE_PINNED); do { ret = __bio_iov_iter_get_pages(bio, iter); } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); From patchwork Mon May 22 20:57:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13251128 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 5B6A1C77B73 for ; Mon, 22 May 2023 20:59:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234633AbjEVU73 (ORCPT ); Mon, 22 May 2023 16:59:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235260AbjEVU7U (ORCPT ); Mon, 22 May 2023 16:59:20 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4979C133 for ; Mon, 22 May 2023 13:58:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684789093; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0UdxcT7QYPFwRvPO4h85pE794/0OGizygn6UovNdu60=; b=dnr4qcNhFOIH7dIjS8LCct4WBfDaj1VZu/avm/fVxLVDiO7VHCYLuT1Apm0VgyWaDLDWvo WSBkFZ4cij4WJkhpGGJE9LQFvxGjh63z96WfWzcYYlCnD5uEgs3J2+D/SUB2wKcJvN2Baa I1QWt0JrkkcETHnw+OnEzgLoBKRXrmw= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-36-QHGrTEFvMROVinDkIKBxuA-1; Mon, 22 May 2023 16:58:10 -0400 X-MC-Unique: QHGrTEFvMROVinDkIKBxuA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 706D1800141; Mon, 22 May 2023 20:58:09 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id E042D140E95D; Mon, 22 May 2023 20:58:06 +0000 (UTC) From: David Howells To: Jens Axboe , Al Viro , Christoph Hellwig Cc: David Howells , Matthew Wilcox , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Hellwig , John Hubbard Subject: [PATCH v21 6/6] block: convert bio_map_user_iov to use iov_iter_extract_pages Date: Mon, 22 May 2023 21:57:44 +0100 Message-Id: <20230522205744.2825689-7-dhowells@redhat.com> In-Reply-To: <20230522205744.2825689-1-dhowells@redhat.com> References: <20230522205744.2825689-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This will pin pages or leave them unaltered rather than getting a ref on them as appropriate to the iterator. The pages need to be pinned for DIO rather than having refs taken on them to prevent VM copy-on-write from malfunctioning during a concurrent fork() (the result of the I/O could otherwise end up being visible to/affected by the child process). Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: John Hubbard cc: Al Viro cc: Jens Axboe cc: Jan Kara cc: Matthew Wilcox cc: Logan Gunthorpe cc: linux-block@vger.kernel.org Reviewed-by: Jan Kara --- Notes: ver #10) - Drop bio_set_cleanup_mode(), open coding it instead. ver #8) - Split the patch up a bit [hch]. - We should only be using pinned/non-pinned pages and not ref'd pages, so adjust the comments appropriately. ver #7) - Don't treat BIO_PAGE_REFFED/PINNED as being the same as FOLL_GET/PIN. ver #5) - Transcribe the FOLL_* flags returned by iov_iter_extract_pages() to BIO_* flags and got rid of bi_cleanup_mode. - Replaced BIO_NO_PAGE_REF to BIO_PAGE_REFFED in the preceding patch. block/blk-map.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) diff --git a/block/blk-map.c b/block/blk-map.c index 33d9f6e89ba6..3551c3ff17cf 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -281,22 +281,21 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter, if (blk_queue_pci_p2pdma(rq->q)) extraction_flags |= ITER_ALLOW_P2PDMA; + if (iov_iter_extract_will_pin(iter)) + bio_set_flag(bio, BIO_PAGE_PINNED); - bio_set_flag(bio, BIO_PAGE_REFFED); while (iov_iter_count(iter)) { - struct page **pages, *stack_pages[UIO_FASTIOV]; + struct page *stack_pages[UIO_FASTIOV]; + struct page **pages = stack_pages; ssize_t bytes; size_t offs; int npages; - if (nr_vecs <= ARRAY_SIZE(stack_pages)) { - pages = stack_pages; - bytes = iov_iter_get_pages(iter, pages, LONG_MAX, - nr_vecs, &offs, extraction_flags); - } else { - bytes = iov_iter_get_pages_alloc(iter, &pages, - LONG_MAX, &offs, extraction_flags); - } + if (nr_vecs > ARRAY_SIZE(stack_pages)) + pages = NULL; + + bytes = iov_iter_extract_pages(iter, &pages, LONG_MAX, + nr_vecs, extraction_flags, &offs); if (unlikely(bytes <= 0)) { ret = bytes ? bytes : -EFAULT; goto out_unmap; @@ -318,7 +317,7 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter, if (!bio_add_hw_page(rq->q, bio, page, n, offs, max_sectors, &same_page)) { if (same_page) - put_page(page); + bio_release_page(bio, page); break; } @@ -330,7 +329,7 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter, * release the pages we didn't map into the bio, if any */ while (j < npages) - put_page(pages[j++]); + bio_release_page(bio, pages[j++]); if (pages != stack_pages) kvfree(pages); /* couldn't stuff something into bio? */