From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f197.google.com (mail-qt0-f197.google.com [209.85.216.197]) by kanga.kvack.org (Postfix) with ESMTP id 8C1D76B0495 for ; Tue, 8 Aug 2017 04:49:32 -0400 (EDT) Received: by mail-qt0-f197.google.com with SMTP id s26so12659451qts.8 for ; Tue, 08 Aug 2017 01:49:32 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id x4si765240qke.376.2017.08.08.01.49.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Aug 2017 01:49:31 -0700 (PDT) From: Ming Lei Subject: [PATCH v3 16/49] block: bounce: don't access bio->bi_io_vec in copy_to_high_bio_irq Date: Tue, 8 Aug 2017 16:45:15 +0800 Message-Id: <20170808084548.18963-17-ming.lei@redhat.com> In-Reply-To: <20170808084548.18963-1-ming.lei@redhat.com> References: <20170808084548.18963-1-ming.lei@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Jens Axboe , Christoph Hellwig , Huang Ying , Andrew Morton , Alexander Viro Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Ming Lei As we need to support multipage bvecs, so don't access bio->bi_io_vec in copy_to_high_bio_irq(), and just use the standard iterator to do that. Signed-off-by: Ming Lei --- block/bounce.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/block/bounce.c b/block/bounce.c index e57cf2bdcd27..50e965a15295 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -112,24 +112,30 @@ int init_emergency_isa_pool(void) static void copy_to_high_bio_irq(struct bio *to, struct bio *from) { unsigned char *vfrom; - struct bio_vec tovec, *fromvec = from->bi_io_vec; + struct bio_vec tovec, fromvec; struct bvec_iter iter; + /* + * The bio of @from is created by bounce, so we can iterate + * its bvec from start to end, but the @from->bi_iter can't be + * trusted because it might be changed by splitting. + */ + struct bvec_iter from_iter = BVEC_ITER_ALL_INIT; bio_for_each_segment(tovec, to, iter) { - if (tovec.bv_page != fromvec->bv_page) { + fromvec = bio_iter_iovec(from, from_iter); + if (tovec.bv_page != fromvec.bv_page) { /* * fromvec->bv_offset and fromvec->bv_len might have * been modified by the block layer, so use the original * copy, bounce_copy_vec already uses tovec->bv_len */ - vfrom = page_address(fromvec->bv_page) + + vfrom = page_address(fromvec.bv_page) + tovec.bv_offset; bounce_copy_vec(&tovec, vfrom); flush_dcache_page(tovec.bv_page); } - - fromvec++; + bio_advance_iter(from, &from_iter, tovec.bv_len); } } -- 2.9.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org