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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D937EC77B75 for ; Tue, 23 May 2023 08:10:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235408AbjEWIKF (ORCPT ); Tue, 23 May 2023 04:10:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236099AbjEWIJm (ORCPT ); Tue, 23 May 2023 04:09:42 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6526E5C; Tue, 23 May 2023 01:08:49 -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-out2.suse.de (Postfix) with ESMTPS id 07E2C2041B; Tue, 23 May 2023 08:08:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1684829325; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=+dEVVbvNrEYxHr4b/vv5A6cTh8OogUJDKNko7MtzH3g=; b=aqMp1lCSDbRRddYRBHCTzgZ8x1pcGP1ICj8oT4unMeLI5CnphXMKLrBRpZ8cLmiW5m3sCY WeOiDgGdSZ+NKlLvTwbYdwdBaQAwX1+PsaFg8vEQkHvY/8P4JhZtJMhoc6cmh4zoiyQjew RoTL2lw9yc1D3Ur55S/L9aihQPQo1vo= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1684829325; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=+dEVVbvNrEYxHr4b/vv5A6cTh8OogUJDKNko7MtzH3g=; b=85tYuyPi+5yLNN+ZI7057j42rnEVNsfXfZ4tHlK3EXP7KbqEhAAAAMKpvtPHvPPqQXevj2 nQ+SP7q+8zjv1UDQ== 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 ED42B13A10; Tue, 23 May 2023 08:08:44 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 4o3rOYx0bGTrMQAAMHmgww (envelope-from ); Tue, 23 May 2023 08:08:44 +0000 Received: by quack3.suse.cz (Postfix, from userid 1000) id 8C0CCA075D; Tue, 23 May 2023 10:08:44 +0200 (CEST) Date: Tue, 23 May 2023 10:08:44 +0200 From: Jan Kara To: David Howells Cc: Jens Axboe , Al Viro , Christoph Hellwig , 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: Re: [PATCH v21 4/6] block: Add BIO_PAGE_PINNED and associated infrastructure Message-ID: <20230523080844.uxj3q244bcb3cot3@quack3> References: <20230522205744.2825689-1-dhowells@redhat.com> <20230522205744.2825689-5-dhowells@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230522205744.2825689-5-dhowells@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Mon 22-05-23 21:57:42, David Howells wrote: > 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 Looks good to me. Feel free to add: Reviewed-by: Jan Kara Honza > --- > > 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 */ > -- Jan Kara SUSE Labs, CR