From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-op-o15.zoho.com (sender4-op-o15.zoho.com [136.143.188.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 108B3366DA4; Sun, 21 Jun 2026 13:03:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.15 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782047005; cv=pass; b=cYtSRE6sS6bMerl1rDr/Q5LB1NniWOYFnbBAkurSaeQXtbYMZgK2jNXTB8Oo8B/gOKVkpIt/PK4jj04jMeRrdfSqv23q7d3KM/kE3t9FtBmpwxKeU82+TNdRdCma2EMxFOlgS/nOxLJY048W9shA9rXlArVRP/T7hI3gYDhbhYk= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782047005; c=relaxed/simple; bh=itjLrkKJEW81RURIxDECsGtTLBhbeI004y7GPmhHinc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nGaLpc+S+tmjOvInEMlEUygj9+JL33K9+2p8hC2r6LcytcmzutA1m14EY7/JzOO28yrdmPhrqesmdn+6dCLPrfWgv5wtPu9QwrYwPdBDiOoaIlzEW7G/aQXFLYUUcXunjtNhyurJIOiAGzAQpYJndwiNO4h1mFyxj9mRDCpqsZ4= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.beauty; spf=pass smtp.mailfrom=linux.beauty; dkim=pass (1024-bit key) header.d=linux.beauty header.i=me@linux.beauty header.b=i4EOrt9z; arc=pass smtp.client-ip=136.143.188.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.beauty Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.beauty Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.beauty header.i=me@linux.beauty header.b="i4EOrt9z" ARC-Seal: i=1; a=rsa-sha256; t=1782046996; cv=none; d=zohomail.com; s=zohoarc; b=YDIit72m4ticVGIAgvj14rN8bamQK7mkEwYY0VamG9eXaKwuHPHhbNf8jO1otq08XxmaccpQK5t0IXn76O2qWH2an/ZXKkQHyZomJ/qo29LsZMOOyffVj5kmbOUmJGlyhE4fRgAw7SotOd9tyr3sNA5rRhy7w/y2gzFcWpZB8Qg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1782046996; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=c0EOLBoih0cc+8cnP+Tzr7COxL+v2rD15YCFnpCQMeg=; b=P5nsVLzpjoFEAV1jpyShma37Cm/s2PayE5pzX8wrhmEqdMj86uWLdv0f+c+JSNlIFDT4CxXL4QYYaQfbujkFmSaYCmlrmce8ifY+Ov1DaeoENo/zVTi/FGEbDsWT0xcT2fQ5A+Y9653Zd48LbgpAb6ohatPh5sJuOJZXs+ep4PU= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=linux.beauty; spf=pass smtp.mailfrom=me@linux.beauty; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1782046996; s=zmail; d=linux.beauty; i=me@linux.beauty; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=c0EOLBoih0cc+8cnP+Tzr7COxL+v2rD15YCFnpCQMeg=; b=i4EOrt9zfwk3FQH38nO2rWjQ1fHF/8lYPI/Cgz4CgJRU49Sax6afXjZ3tN2SQcHS UdUslO8hV40hjDC4FYUVr/NpXQR1agoBCGAYSLpgbMtqsYkaNF4gWxUl6FTEaywVNp+ UokEd9QyDR0SQssNmDsClbR+ClBKbS42qVfB3eXY= Received: by mx.zohomail.com with SMTPS id 1782046992618983.5404623082977; Sun, 21 Jun 2026 06:03:12 -0700 (PDT) From: Li Chen To: Pankaj Gupta , Dan Williams , Vishal Verma , Dave Jiang , Ira Weiny , Alison Schofield , virtualization@lists.linux.dev, nvdimm@lists.linux.dev Cc: linux-kernel@vger.kernel.org, Li Chen Subject: [PATCH v6 03/12] nvdimm: pmem: guard data loop for dataless bios Date: Sun, 21 Jun 2026 21:02:34 +0800 Message-ID: <20260621130246.2973254-4-me@linux.beauty> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260621130246.2973254-1-me@linux.beauty> References: <20260621130246.2973254-1-me@linux.beauty> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-ZohoMailClient: External pmem_submit_bio() handles flush-only bios before and after the data loop. Keep dataless bios out of bio_for_each_segment() so the data path only walks bios that actually carry bvec data. Signed-off-by: Li Chen --- Changes in v6: - New patch. drivers/nvdimm/pmem.c | 36 +++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 05d3de33e2706..82ee1ddb3a445 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -217,23 +217,29 @@ static void pmem_submit_bio(struct bio *bio) } } - do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue); - if (do_acct) - start = bio_start_io_acct(bio); - bio_for_each_segment(bvec, bio, iter) { - if (op_is_write(bio_op(bio))) - rc = pmem_do_write(pmem, bvec.bv_page, bvec.bv_offset, - iter.bi_sector, bvec.bv_len); - else - rc = pmem_do_read(pmem, bvec.bv_page, bvec.bv_offset, - iter.bi_sector, bvec.bv_len); - if (rc) { - bio->bi_status = rc; - break; + if (bio_has_data(bio)) { + do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue); + if (do_acct) + start = bio_start_io_acct(bio); + bio_for_each_segment(bvec, bio, iter) { + if (op_is_write(bio_op(bio))) + rc = pmem_do_write(pmem, bvec.bv_page, + bvec.bv_offset, + iter.bi_sector, + bvec.bv_len); + else + rc = pmem_do_read(pmem, bvec.bv_page, + bvec.bv_offset, + iter.bi_sector, + bvec.bv_len); + if (rc) { + bio->bi_status = rc; + break; + } } + if (do_acct) + bio_end_io_acct(bio, start); } - if (do_acct) - bio_end_io_acct(bio, start); if ((bio->bi_opf & REQ_FUA) && !bio->bi_status) ret = nvdimm_flush(nd_region, bio); -- 2.52.0