diff options
| -rw-r--r-- | include/linux/uio.h | 2 | ||||
| -rw-r--r-- | mm/iov_iter.c | 15 |
2 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h index 07a022641996..71880299ed48 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -98,6 +98,8 @@ ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages, size_t maxsize, size_t *start); int iov_iter_npages(const struct iov_iter *i, int maxpages); +const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags); + static inline size_t iov_iter_count(struct iov_iter *i) { return i->count; diff --git a/mm/iov_iter.c b/mm/iov_iter.c index 827732047da1..9d96e283520c 100644 --- a/mm/iov_iter.c +++ b/mm/iov_iter.c @@ -751,3 +751,18 @@ int iov_iter_npages(const struct iov_iter *i, int maxpages) return npages; } EXPORT_SYMBOL(iov_iter_npages); + +const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags) +{ + *new = *old; + if (new->type & ITER_BVEC) + return new->bvec = kmemdup(new->bvec, + new->nr_segs * sizeof(struct bio_vec), + flags); + else + /* iovec and kvec have identical layout */ + return new->iov = kmemdup(new->iov, + new->nr_segs * sizeof(struct iovec), + flags); +} +EXPORT_SYMBOL(dup_iter); |