From 357f435d8a0d32068c75f3c7176434d992b3adb7 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 8 Apr 2016 19:05:19 -0400 Subject: fix the copy vs. map logics in blk_rq_map_user_iov() Signed-off-by: Al Viro --- block/blk-map.c | 47 ++++++++--------------------------------------- 1 file changed, 8 insertions(+), 39 deletions(-) (limited to 'block/blk-map.c') diff --git a/block/blk-map.c b/block/blk-map.c index a54f0543b956..b9f88b7751fb 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -9,24 +9,6 @@ #include "blk.h" -static bool iovec_gap_to_prv(struct request_queue *q, - struct iovec *prv, struct iovec *cur) -{ - unsigned long prev_end; - - if (!queue_virt_boundary(q)) - return false; - - if (prv->iov_base == NULL && prv->iov_len == 0) - /* prv is not set - don't check */ - return false; - - prev_end = (unsigned long)(prv->iov_base + prv->iov_len); - - return (((unsigned long)cur->iov_base & queue_virt_boundary(q)) || - prev_end & queue_virt_boundary(q)); -} - int blk_rq_append_bio(struct request_queue *q, struct request *rq, struct bio *bio) { @@ -125,31 +107,18 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, struct rq_map_data *map_data, const struct iov_iter *iter, gfp_t gfp_mask) { - struct iovec iov, prv = {.iov_base = NULL, .iov_len = 0}; - bool copy = (q->dma_pad_mask & iter->count) || map_data; + bool copy = false; + unsigned long align = q->dma_pad_mask | queue_dma_alignment(q); struct bio *bio = NULL; struct iov_iter i; int ret; - if (!iter || !iter->count) - return -EINVAL; - - iov_for_each(iov, i, *iter) { - unsigned long uaddr = (unsigned long) iov.iov_base; - - if (!iov.iov_len) - return -EINVAL; - - /* - * Keep going so we check length of all segments - */ - if ((uaddr & queue_dma_alignment(q)) || - iovec_gap_to_prv(q, &prv, &iov)) - copy = true; - - prv.iov_base = iov.iov_base; - prv.iov_len = iov.iov_len; - } + if (map_data) + copy = true; + else if (iov_iter_alignment(iter) & align) + copy = true; + else if (queue_virt_boundary(q)) + copy = queue_virt_boundary(q) & iov_iter_gap_alignment(iter); i = *iter; do { -- cgit v1.2.3-59-g8ed1b