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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 3D0B8C34049 for ; Tue, 18 Feb 2020 21:10:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0DA4F24654 for ; Tue, 18 Feb 2020 21:10:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="RiFt7CZu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727648AbgBRVKQ (ORCPT ); Tue, 18 Feb 2020 16:10:16 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:30225 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727463AbgBRVKQ (ORCPT ); Tue, 18 Feb 2020 16:10:16 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582060215; h=from:from:reply-to:subject:subject: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=xkdUovKifhRODs8J1uyT4NjG5UsLCNrvnkk18Wikk2k=; b=RiFt7CZuxtzT6hCMjyHRn6chEy4W0HphJGfAWMgsuysWu4uuAeZHE0wEA1GmxH76WJElem c/HvZ/zqvO3g5DZD61SWD3K7XTeh9R0KbPVboBdAXO0Kv4bSBs8SJ/2j4OsE2fzdWNf5Nj 8OMfIh50OU3/omDJXjrg57ycB5CGLfY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-237-z_QZstOwMa-ZO7deoOum_w-1; Tue, 18 Feb 2020 16:10:13 -0500 X-MC-Unique: z_QZstOwMa-ZO7deoOum_w-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D29BF107ACCA; Tue, 18 Feb 2020 21:10:11 +0000 (UTC) Received: from horse.redhat.com (unknown [10.18.25.35]) by smtp.corp.redhat.com (Postfix) with ESMTP id BAD1490779; Tue, 18 Feb 2020 21:10:08 +0000 (UTC) Received: by horse.redhat.com (Postfix, from userid 10451) id 36D182257D2; Tue, 18 Feb 2020 16:10:08 -0500 (EST) Date: Tue, 18 Feb 2020 16:10:08 -0500 From: Vivek Goyal To: Christoph Hellwig Cc: linux-fsdevel@vger.kernel.org, linux-nvdimm@lists.01.org, dan.j.williams@intel.com, vishal.l.verma@intel.com, dm-devel@redhat.com Subject: Re: [dm-devel] [PATCH v4 2/7] pmem: Enable pmem_do_write() to deal with arbitrary ranges Message-ID: <20200218211008.GB19413@redhat.com> References: <20200217181653.4706-1-vgoyal@redhat.com> <20200217181653.4706-3-vgoyal@redhat.com> <20200218170928.GB30766@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200218170928.GB30766@infradead.org> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Feb 18, 2020 at 09:09:28AM -0800, Christoph Hellwig wrote: > On Mon, Feb 17, 2020 at 01:16:48PM -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 | 32 +++++++++++++++++++++++--------- > > 1 file changed, 23 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c > > index 075b11682192..fae8f67da9de 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 (is_bad_pmem(&pmem->bb, sector_start, > > + nr_sectors << SECTOR_SHIFT)) > > + bad_pmem = true; > > + } > > > > /* > > * Note that we write the data both before and after > > @@ -181,7 +189,13 @@ static blk_status_t pmem_do_write(struct pmem_device *pmem, > > flush_dcache_page(page); > > write_pmem(pmem_addr, page, page_off, len); > > if (unlikely(bad_pmem)) { > > - rc = pmem_clear_poison(pmem, pmem_off, len); > > + /* > > + * 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. > > + */ > > + rc = pmem_clear_poison(pmem, ALIGN(pmem_real_off, SECTOR_SIZE), > > + nr_sectors << SECTOR_SHIFT); > > write_pmem(pmem_addr, page, page_off, len); > > I'm still scared about the as of now commnet. If the interface to > clearing poison is page aligned I think we should document that in the > actual pmem_clear_poison function, and make that take the unaligned > offset. I also think we want some feedback from Dan or other what the > official interface is instead of "seems to work". Ok, I am adding one more patch to series and enabling pmem_clear_poison() to accept arbitrary offset and length and let it align offset and length to sector boundary. Keeping it in a separate patch so that Dan can have a close look at it and make sure I am doing things correctly. Here is the new patch. I will post the V5 soon with this new patch. Thanks Vivek Subject: drivers/pmem: Allow pmem_clear_poison() to accept arbitrary offset and len Currently pmem_clear_poison() expects offset and len to be sector aligned. Atleast that seems to be the assumption with which code has been written. It is called only from pmem_do_bvec() which is called only from pmem_rw_page() and pmem_make_request() which will only passe sector aligned offset and len. Soon we want use this function from dax_zero_page_range() code path which can try to zero arbitrary range of memory with-in a page. So update this function to assume that offset and length can be arbitrary and do the necessary alignments as needed. nvdimm_clear_poison() seems to assume offset and len to be aligned to clear_err_unit boundary. But this is currently internal detail and is not exported for others to use. So for now, continue to align offset and length to SECTOR_SIZE boundary. Improving it further and to align it to clear_err_unit boundary is a TODO item for future. Signed-off-by: Vivek Goyal --- drivers/nvdimm/pmem.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 075b11682192..e72959203253 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -74,14 +74,28 @@ static blk_status_t pmem_clear_poison(struct pmem_device *pmem, sector_t sector; long cleared; blk_status_t rc = BLK_STS_OK; + phys_addr_t start_aligned, end_aligned; + unsigned int len_aligned; - sector = (offset - pmem->data_offset) / 512; + /* + * Callers can pass arbitrary offset and len. But nvdimm_clear_poison() + * expects memory offset and length to meet certain alignment + * restrction (clear_err_unit). Currently nvdimm does not export + * required alignment. So align offset and length to sector boundary + * before passing it to nvdimm_clear_poison(). + */ + start_aligned = ALIGN(offset, SECTOR_SIZE); + end_aligned = ALIGN_DOWN((offset + len), SECTOR_SIZE) - 1; + len_aligned = end_aligned - start_aligned + 1; + + sector = (start_aligned - pmem->data_offset) / 512; - cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len); - if (cleared < len) + cleared = nvdimm_clear_poison(dev, pmem->phys_addr + start_aligned, + len_aligned); + if (cleared < len_aligned) rc = BLK_STS_IOERR; if (cleared > 0 && cleared / 512) { - hwpoison_clear(pmem, pmem->phys_addr + offset, cleared); + hwpoison_clear(pmem, pmem->phys_addr + start_aligned, cleared); cleared /= 512; dev_dbg(dev, "%#llx clear %ld sector%s\n", (unsigned long long) sector, cleared, -- 2.20.1