From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:34942 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755141AbdCPQOe (ORCPT ); Thu, 16 Mar 2017 12:14:34 -0400 From: Ming Lei To: Shaohua Li , Jens Axboe , linux-raid@vger.kernel.org, linux-block@vger.kernel.org, Christoph Hellwig Cc: Ming Lei Subject: [PATCH v3 03/14] md: prepare for managing resync I/O pages in clean way Date: Fri, 17 Mar 2017 00:12:24 +0800 Message-Id: <20170316161235.27110-4-tom.leiming@gmail.com> In-Reply-To: <20170316161235.27110-1-tom.leiming@gmail.com> References: <20170316161235.27110-1-tom.leiming@gmail.com> Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org Now resync I/O use bio's bec table to manage pages, this way is very hacky, and may not work any more once multipage bvec is introduced. So introduce helpers and new data structure for managing resync I/O pages more cleanly. Signed-off-by: Ming Lei --- drivers/md/md.h | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/drivers/md/md.h b/drivers/md/md.h index 1d63239a1be4..20c48032493b 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -720,4 +720,54 @@ static inline void mddev_check_writesame(struct mddev *mddev, struct bio *bio) #define RESYNC_BLOCK_SIZE (64*1024) #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) +/* for managing resync I/O pages */ +struct resync_pages { + unsigned idx; /* for get/put page from the pool */ + void *raid_bio; + struct page *pages[RESYNC_PAGES]; +}; + +static inline int resync_alloc_pages(struct resync_pages *rp, + gfp_t gfp_flags) +{ + int i; + + for (i = 0; i < RESYNC_PAGES; i++) { + rp->pages[i] = alloc_page(gfp_flags); + if (!rp->pages[i]) + goto out_free; + } + + return 0; + + out_free: + while (--i >= 0) + put_page(rp->pages[i]); + return -ENOMEM; +} + +static inline void resync_free_pages(struct resync_pages *rp) +{ + int i; + + for (i = 0; i < RESYNC_PAGES; i++) + put_page(rp->pages[i]); +} + +static inline void resync_get_all_pages(struct resync_pages *rp) +{ + int i; + + for (i = 0; i < RESYNC_PAGES; i++) + get_page(rp->pages[i]); +} + +static inline struct page *resync_fetch_page(struct resync_pages *rp, + unsigned idx) +{ + if (WARN_ON_ONCE(idx >= RESYNC_PAGES)) + return NULL; + return rp->pages[idx]; +} + #endif /* _MD_MD_H */ -- 2.9.3