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 X-Spam-Level: X-Spam-Status: No, score=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7614BC35254 for ; Mon, 17 Feb 2020 13:23:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 49AAA2070B for ; Mon, 17 Feb 2020 13:23:10 +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="Wg1XDz5a" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728442AbgBQNXJ (ORCPT ); Mon, 17 Feb 2020 08:23:09 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:36478 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728124AbgBQNXJ (ORCPT ); Mon, 17 Feb 2020 08:23:09 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ByxHNx18slAjQKwWQOPPOSwhUVNs5MumxpbzTsFX1YE=; b=Wg1XDz5aNxcq5v1gyNrnTidPVe 8HqRWPY8J3R0MOaBmB84CGVgjJW8Wkm26X9SxtIyNA23KgARIHqBYzhF7l5Xe5CPKp6zeIvMBLSSo Zp/KPaNj/+C5aTS1vM8gSadnQ0MtWm+OQtWROKv1HSCV6fgOy9s0fCfGuJSdV/ko28taJVN4QMeDw TvcYwpurjpczt6e6i1epwKNk544VeTVuBOqrynLRMIGHbumNS4rvWcryZ/unl9DonoDWAtau5G6zx 7m2E/xMW+pIO739uAVglRnCPOJ9hu0fInTTEkea6UsQdAXsetRo/Jax9ZOmDTCQaO61PK+AC2kQDB 4wFeg11w==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1j3gMf-0002bB-FE; Mon, 17 Feb 2020 13:23:09 +0000 Date: Mon, 17 Feb 2020 05:23:09 -0800 From: Christoph Hellwig To: Vivek Goyal Cc: linux-fsdevel@vger.kernel.org, linux-nvdimm@lists.01.org, hch@infradead.org, dan.j.williams@intel.com, dm-devel@redhat.com, vishal.l.verma@intel.com Subject: Re: [PATCH v3 2/7] pmem: Enable pmem_do_write() to deal with arbitrary ranges Message-ID: <20200217132309.GC14490@infradead.org> References: <20200207202652.1439-1-vgoyal@redhat.com> <20200207202652.1439-3-vgoyal@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200207202652.1439-3-vgoyal@redhat.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, Feb 07, 2020 at 03:26:47PM -0500, Vivek Goyal wrote: > Currently pmem_do_write() is written with assumption that all I/O is > sector aligned. Soon I want to use this function in zero_page_range() > where range passed in does not have to be sector aligned. > > Modify this function to be able to deal with an arbitrary range. Which > is specified by pmem_off and len. > > Signed-off-by: Vivek Goyal > --- > drivers/nvdimm/pmem.c | 30 ++++++++++++++++++++++-------- > 1 file changed, 22 insertions(+), 8 deletions(-) > > diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c > index 9ad07cb8c9fc..281fe04d25fd 100644 > --- a/drivers/nvdimm/pmem.c > +++ b/drivers/nvdimm/pmem.c > @@ -154,15 +154,23 @@ static blk_status_t pmem_do_read(struct pmem_device *pmem, > > static blk_status_t pmem_do_write(struct pmem_device *pmem, > struct page *page, unsigned int page_off, > - sector_t sector, unsigned int len) > + u64 pmem_off, unsigned int len) > { > blk_status_t rc = BLK_STS_OK; > bool bad_pmem = false; > - phys_addr_t pmem_off = sector * 512 + pmem->data_offset; > - void *pmem_addr = pmem->virt_addr + pmem_off; > - > - if (unlikely(is_bad_pmem(&pmem->bb, sector, len))) > - bad_pmem = true; > + phys_addr_t pmem_real_off = pmem_off + pmem->data_offset; > + void *pmem_addr = pmem->virt_addr + pmem_real_off; > + sector_t sector_start, sector_end; > + unsigned nr_sectors; > + > + sector_start = DIV_ROUND_UP(pmem_off, SECTOR_SIZE); > + sector_end = (pmem_off + len) >> SECTOR_SHIFT; > + if (sector_end > sector_start) { > + nr_sectors = sector_end - sector_start; > + if (unlikely(is_bad_pmem(&pmem->bb, sector_start, > + nr_sectors << SECTOR_SHIFT))) > + bad_pmem = true; I don't think an unlikely annotation makes much sense for assigning a boolean value to a flag variable. > + /* > + * Pass sector aligned offset and length. That seems > + * to work as of now. Other finer grained alignment > + * cases can be addressed later if need be. > + */ This comment seems pretty scary. What other cases can you think of?