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authorDavid S. Miller <davem@davemloft.net>2017-04-15 21:16:30 -0400
committerDavid S. Miller <davem@davemloft.net>2017-04-15 21:16:30 -0400
commit6b6cbc1471676402565e958674523d06213b82d7 (patch)
treea66d41d276e5eb400e27641f24f34032fe1b9275 /lib
parentce07183282975026716107d36fd3f5f93de76668 (diff)
parent1bf4b1268e66d9364fc6fd41f906bc01458530ac (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were simply overlapping changes. In the net/ipv4/route.c case the code had simply moved around a little bit and the same fix was made in both 'net' and 'net-next'. In the net/sched/sch_generic.c case a fix in 'net' happened at the same time that a new argument was added to qdisc_hash_add(). Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'lib')
-rw-r--r--lib/iov_iter.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index e68604ae3ced..60abc44385b7 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -786,6 +786,68 @@ void iov_iter_advance(struct iov_iter *i, size_t size)
}
EXPORT_SYMBOL(iov_iter_advance);
+void iov_iter_revert(struct iov_iter *i, size_t unroll)
+{
+ if (!unroll)
+ return;
+ i->count += unroll;
+ if (unlikely(i->type & ITER_PIPE)) {
+ struct pipe_inode_info *pipe = i->pipe;
+ int idx = i->idx;
+ size_t off = i->iov_offset;
+ while (1) {
+ size_t n = off - pipe->bufs[idx].offset;
+ if (unroll < n) {
+ off -= (n - unroll);
+ break;
+ }
+ unroll -= n;
+ if (!unroll && idx == i->start_idx) {
+ off = 0;
+ break;
+ }
+ if (!idx--)
+ idx = pipe->buffers - 1;
+ off = pipe->bufs[idx].offset + pipe->bufs[idx].len;
+ }
+ i->iov_offset = off;
+ i->idx = idx;
+ pipe_truncate(i);
+ return;
+ }
+ if (unroll <= i->iov_offset) {
+ i->iov_offset -= unroll;
+ return;
+ }
+ unroll -= i->iov_offset;
+ if (i->type & ITER_BVEC) {
+ const struct bio_vec *bvec = i->bvec;
+ while (1) {
+ size_t n = (--bvec)->bv_len;
+ i->nr_segs++;
+ if (unroll <= n) {
+ i->bvec = bvec;
+ i->iov_offset = n - unroll;
+ return;
+ }
+ unroll -= n;
+ }
+ } else { /* same logics for iovec and kvec */
+ const struct iovec *iov = i->iov;
+ while (1) {
+ size_t n = (--iov)->iov_len;
+ i->nr_segs++;
+ if (unroll <= n) {
+ i->iov = iov;
+ i->iov_offset = n - unroll;
+ return;
+ }
+ unroll -= n;
+ }
+ }
+}
+EXPORT_SYMBOL(iov_iter_revert);
+
/*
* Return the count of just the current iov_iter segment.
*/
@@ -839,6 +901,7 @@ void iov_iter_pipe(struct iov_iter *i, int direction,
i->idx = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
i->iov_offset = 0;
i->count = count;
+ i->start_idx = i->idx;
}
EXPORT_SYMBOL(iov_iter_pipe);