From patchwork Mon May 27 15:40:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mikulas Patocka X-Patchwork-Id: 13675527 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 BF47961FCB for ; Mon, 27 May 2024 15:40:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716824422; cv=none; b=fze6LIyDBRaCXy8BZtzLFYT0xpypbxgHdNNRak9eJxUY/6trHisjFFKW6d3lHu65ZXPJm1XrnaJE4kOPRElp78sYBGMZTNEoml30VYmRQcIhy+lLnTD0Z/+doeFf3i4biTiEX2RUCojI70xjKO57dwaHxoPiorVrXtZJ2C+D1JM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716824422; c=relaxed/simple; bh=4yKJZGIADXEL6IMCwFp1IXjxf7YVdLWjyGJQu6FHsJI=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=MYLSuydF8Si4+f0IcCKagBkcOhfvkt19KY/+koZp4M6jveDIioFIyYHrkwz9AJ2JJRoYlEfqHav8+scFyOUq88H4LvoFbCST2k5w4CnBuNvxuXCElWomNMQwirk8Aa/FQk08XVP8GMwpS61wWGWy26tDYrR55eDAU8lrsWuHmJ8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=VtC6y/Zl; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="VtC6y/Zl" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1716824418; 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=1H9GxV1pJcvxFjM13xgSobQ66nYiI8s6MaV3OMmDrjk=; b=VtC6y/ZlzKHn+yKrLQB7h13IaDwyMYQXMUilpiqmtVfytMYOdXB1SFmURQaS43o+EFJLsM JbnPzeQIBUxzNYKly6t6kBdDT8e2I7z+8Pf+GiujjsBYi37ER1BU/5p4olbpV5CmMPi1CA COhSV+eN9b5shmm4RPp+2Xx3Is/KU54= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-333-rYImaBXFOdq56BZbCHZY2g-1; Mon, 27 May 2024 11:40:11 -0400 X-MC-Unique: rYImaBXFOdq56BZbCHZY2g-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E07BB380670C; Mon, 27 May 2024 15:40:10 +0000 (UTC) Received: from file1-rdu.file-001.prod.rdu2.dc.redhat.com (unknown [10.11.5.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D53563C27; Mon, 27 May 2024 15:40:10 +0000 (UTC) Received: by file1-rdu.file-001.prod.rdu2.dc.redhat.com (Postfix, from userid 12668) id CE91130C1C33; Mon, 27 May 2024 15:40:10 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by file1-rdu.file-001.prod.rdu2.dc.redhat.com (Postfix) with ESMTP id CDA033C542; Mon, 27 May 2024 17:40:10 +0200 (CEST) Date: Mon, 27 May 2024 17:40:10 +0200 (CEST) From: Mikulas Patocka To: Axboe , Keith Busch , Christoph Hellwig , Sagi Grimberg , Mike Snitzer , Milan Broz , Anuj gupta cc: linux-block@vger.kernel.org, dm-devel@lists.linux.dev, linux-nvme@lists.infradead.org Subject: [PATCH 1/2 v4] block: change rq_integrity_vec to respect the iterator In-Reply-To: <719d2e-b0e6-663c-ec38-acf939e4a04b@redhat.com> Message-ID: <49d1afaa-f934-6ed2-a678-e0d428c63a65@redhat.com> References: <719d2e-b0e6-663c-ec38-acf939e4a04b@redhat.com> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.1 If we allocate a bio that is larger than NVMe maximum request size, attach integrity metadata to it and send it to the NVMe subsystem, the integrity metadata will be corrupted. Splitting the bio works correctly. The function bio_split will clone the bio, trim the iterator of the first bio and advance the iterator of the second bio. However, the function rq_integrity_vec has a bug - it returns the first vector of the bio's metadata and completely disregards the metadata iterator that was advanced when the bio was split. Thus, the second bio uses the same metadata as the first bio and this leads to metadata corruption. This commit changes rq_integrity_vec, so that it calls mp_bvec_iter_bvec instead of returning the first vector. mp_bvec_iter_bvec reads the iterator and uses it to build a bvec for the current position in the iterator. The "queue_max_integrity_segments(rq->q) > 1" check was removed, because the updated rq_integrity_vec function works correctly with multiple segments. Signed-off-by: Mikulas Patocka Reviewed-by: Anuj Gupta Reviewed-by: Kanchan Joshi Reviewed-by: Christoph Hellwig --- drivers/nvme/host/pci.c | 6 +++--- include/linux/blk-integrity.h | 14 +++++++------- 2 files changed, 10 insertions(+), 10 deletions(-) Index: linux-2.6/drivers/nvme/host/pci.c =================================================================== --- linux-2.6.orig/drivers/nvme/host/pci.c +++ linux-2.6/drivers/nvme/host/pci.c @@ -825,9 +825,9 @@ static blk_status_t nvme_map_metadata(st struct nvme_command *cmnd) { struct nvme_iod *iod = blk_mq_rq_to_pdu(req); + struct bio_vec bv = rq_integrity_vec(req); - iod->meta_dma = dma_map_bvec(dev->dev, rq_integrity_vec(req), - rq_dma_dir(req), 0); + iod->meta_dma = dma_map_bvec(dev->dev, &bv, rq_dma_dir(req), 0); if (dma_mapping_error(dev->dev, iod->meta_dma)) return BLK_STS_IOERR; cmnd->rw.metadata = cpu_to_le64(iod->meta_dma); @@ -966,7 +966,7 @@ static __always_inline void nvme_pci_unm struct nvme_iod *iod = blk_mq_rq_to_pdu(req); dma_unmap_page(dev->dev, iod->meta_dma, - rq_integrity_vec(req)->bv_len, rq_dma_dir(req)); + rq_integrity_vec(req).bv_len, rq_dma_dir(req)); } if (blk_rq_nr_phys_segments(req)) Index: linux-2.6/include/linux/blk-integrity.h =================================================================== --- linux-2.6.orig/include/linux/blk-integrity.h +++ linux-2.6/include/linux/blk-integrity.h @@ -106,14 +106,13 @@ static inline bool blk_integrity_rq(stru } /* - * Return the first bvec that contains integrity data. Only drivers that are - * limited to a single integrity segment should use this helper. + * Return the current bvec that contains the integrity data. bip_iter may be + * advanced to iterate over the integrity data. */ -static inline struct bio_vec *rq_integrity_vec(struct request *rq) +static inline struct bio_vec rq_integrity_vec(struct request *rq) { - if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1)) - return NULL; - return rq->bio->bi_integrity->bip_vec; + return mp_bvec_iter_bvec(rq->bio->bi_integrity->bip_vec, + rq->bio->bi_integrity->bip_iter); } #else /* CONFIG_BLK_DEV_INTEGRITY */ static inline int blk_rq_count_integrity_sg(struct request_queue *q, @@ -179,7 +178,8 @@ static inline int blk_integrity_rq(struc static inline struct bio_vec *rq_integrity_vec(struct request *rq) { - return NULL; + /* the optimizer will remove all calls to this function */ + return (struct bio_vec){ }; } #endif /* CONFIG_BLK_DEV_INTEGRITY */ #endif /* _LINUX_BLK_INTEGRITY_H */