From patchwork Sun Jan 10 21:28:17 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 7998171 Return-Path: X-Original-To: patchwork-linux-nvdimm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0FF22BEEE5 for ; Sun, 10 Jan 2016 21:28:47 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2973120386 for ; Sun, 10 Jan 2016 21:28:46 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4E8F420383 for ; Sun, 10 Jan 2016 21:28:45 +0000 (UTC) Received: from ml01.vlan14.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 42F501A2204; Sun, 10 Jan 2016 13:28:45 -0800 (PST) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by ml01.01.org (Postfix) with ESMTP id 81CB31A21EF for ; Sun, 10 Jan 2016 13:28:43 -0800 (PST) Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga104.fm.intel.com with ESMTP; 10 Jan 2016 13:28:43 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,549,1444719600"; d="scan'208";a="724253958" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.136]) by orsmga003.jf.intel.com with ESMTP; 10 Jan 2016 13:28:43 -0800 Subject: [PATCH v3 07/10] pmem: fail io-requests to known bad blocks From: Dan Williams To: linux-nvdimm@lists.01.org Date: Sun, 10 Jan 2016 13:28:17 -0800 Message-ID: <20160110212817.35359.92849.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <20160110212740.35359.59453.stgit@dwillia2-desk3.amr.corp.intel.com> References: <20160110212740.35359.59453.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.17.1-9-g687f MIME-Version: 1.0 Cc: linux-block@vger.kernel.org X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Check the sectors specified in a read bio to see if they hit a known bad block, and return an error code pmem_do_bvec(). Note that the ->rw_page() is not in a position to return errors. For now, copy the same layering violation present in zram_rw_page() to avoid crashes of the form: kernel BUG at mm/filemap.c:822! [..] Call Trace: [] page_endio+0x1e/0x60 [] mpage_end_io+0x39/0x60 [] bio_endio+0x3f/0x60 [] pmem_make_request+0x111/0x230 [nd_pmem] ...i.e. unlock a page that was already unlocked via pmem_rw_page() => page_endio(). Reported-by: Vishal Verma Signed-off-by: Dan Williams --- drivers/nvdimm/pmem.c | 46 +++++++++++++++++++++++++++++++++++++++------- 1 file changed, 39 insertions(+), 7 deletions(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 2b1f3009f827..d00c659d1304 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -47,7 +47,20 @@ struct pmem_device { static int pmem_major; -static void pmem_do_bvec(struct pmem_device *pmem, struct page *page, +static bool is_bad_pmem(struct badblocks *bb, sector_t sector, unsigned int len) +{ + if (bb->count) { + sector_t first_bad; + int num_bad; + + return !!badblocks_check(bb, sector, len / 512, &first_bad, + &num_bad); + } + + return false; +} + +static int pmem_do_bvec(struct pmem_device *pmem, struct page *page, unsigned int len, unsigned int off, int rw, sector_t sector) { @@ -56,6 +69,8 @@ static void pmem_do_bvec(struct pmem_device *pmem, struct page *page, void __pmem *pmem_addr = pmem->virt_addr + pmem_off; if (rw == READ) { + if (unlikely(is_bad_pmem(&pmem->bb, sector, len))) + return -EIO; memcpy_from_pmem(mem + off, pmem_addr, len); flush_dcache_page(page); } else { @@ -64,10 +79,12 @@ static void pmem_do_bvec(struct pmem_device *pmem, struct page *page, } kunmap_atomic(mem); + return 0; } static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio) { + int rc = 0; bool do_acct; unsigned long start; struct bio_vec bvec; @@ -76,9 +93,15 @@ static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio) struct pmem_device *pmem = bdev->bd_disk->private_data; do_acct = nd_iostat_start(bio, &start); - bio_for_each_segment(bvec, bio, iter) - pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len, bvec.bv_offset, - bio_data_dir(bio), iter.bi_sector); + bio_for_each_segment(bvec, bio, iter) { + rc = pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len, + bvec.bv_offset, bio_data_dir(bio), + iter.bi_sector); + if (rc) { + bio->bi_error = rc; + break; + } + } if (do_acct) nd_iostat_end(bio, start); @@ -93,13 +116,22 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector, struct page *page, int rw) { struct pmem_device *pmem = bdev->bd_disk->private_data; + int rc; - pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector); + rc = pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector); if (rw & WRITE) wmb_pmem(); - page_endio(page, rw & WRITE, 0); - return 0; + /* + * The ->rw_page interface is subtle and tricky. The core + * retries on any error, so we can only invoke page_endio() in + * the successful completion case. Otherwise, we'll see crashes + * caused by double completion. + */ + if (rc == 0) + page_endio(page, rw & WRITE, 0); + + return rc; } static long pmem_direct_access(struct block_device *bdev, sector_t sector,