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 EA1D43ED5A6 for ; Tue, 30 Jun 2026 09:24:33 +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=1782811475; cv=pass; b=feB8/ZD+BKe738L3Q2CQMRBScvCg7Ydwj1q9QodcbErI2TqUGy6K1ConYGTW7cKawKb/owMA0CvfpHnRs/4EPTrn0bo0+bxeIGlCgn7Ld/kGdTAFYxJ+lkz9yT8NPzmoczh5ilD7HzUjTScJCREeaTT6o3VpWipzvRyUG9VVBkg= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782811475; c=relaxed/simple; bh=itjLrkKJEW81RURIxDECsGtTLBhbeI004y7GPmhHinc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uUSJm13W3y/AG5liLF4R+KYPADdanMdZf4KQcKg9WeMtw2t5TKSbEU8IYIHYlqzd8Kv8BOuhNp0R6DTiL643mN/7RKCem7DREdUlzoXsYJurwVWVpfWOeG1O93CPQDF51OysdQWGlnIBGiQHoKWZ3cuqYa8PuYm3dkSurUW1Irk= 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=UnzDV7p9; 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="UnzDV7p9" ARC-Seal: i=1; a=rsa-sha256; t=1782811448; cv=none; d=zohomail.com; s=zohoarc; b=j0g2+QchVXmaHb562lqJQVpKMeZpGIYvRq6Zs8e0yBz6rip0qarIPQNwFZa7kb8CbdOzb9FWpDJOLPoHsDsVxexOrVn+GcYWjWlwIJy/YYBNqDU5oMIKoTpUz0Wl6wjxViMl3dvLtpNEWOG265SlihbtVDZ0pYSylyHZ5JLmd3I= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1782811448; 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=U10akDiquNs49nNkMvjna9rHYjAQuy03qw2ri7IqYmGVAkf/GWXD5nGfuXHjhD/MmXcT03iu+2Q17fSPOSVrJxDHfEx5KLP4GqtgMIPB+e9pV8I37pXGZPxhBY4/hMMEI9XBocIsMCwy78foBuiTsr6hI/GzhlHYkXVg8ZggRXw= 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=1782811447; 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=UnzDV7p9cs1YJdwVOZsKWXm36T5ni3GJnPgAJijWozTAtvtED6iMP90elKTtZIlE VpbE9PtQ3zXfmxtpa+PLvzVYEnlDatC7AkKF5RLJEwIaZKP8kJ1X8VXEBMQw9RsYx/t Og/tLAtLkHD1xIB+L+HHCbwv2QJFIxestlP9/OhM= Received: by mx.zohomail.com with SMTPS id 1782811445296720.8994094732811; Tue, 30 Jun 2026 02:24:05 -0700 (PDT) From: Li Chen To: Pankaj Gupta , Vishal Verma , Dave Jiang , Alison Schofield , virtualization@lists.linux.dev, nvdimm@lists.linux.dev Cc: linux-kernel@vger.kernel.org, Li Chen Subject: [PATCH v7 03/12] nvdimm: pmem: guard data loop for dataless bios Date: Tue, 30 Jun 2026 17:23:28 +0800 Message-ID: <20260630092338.2094628-4-me@linux.beauty> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260630092338.2094628-1-me@linux.beauty> References: <20260630092338.2094628-1-me@linux.beauty> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org 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