diff options
| -rw-r--r-- | lib/iov_iter.c | 55 |
1 files changed, 26 insertions, 29 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 228892dabba6..25f572303801 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -73,19 +73,21 @@ } #define iterate_all_kinds(i, n, v, I, B, K) { \ - size_t skip = i->iov_offset; \ - if (unlikely(i->type & ITER_BVEC)) { \ - struct bio_vec v; \ - struct bvec_iter __bi; \ - iterate_bvec(i, n, v, __bi, skip, (B)) \ - } else if (unlikely(i->type & ITER_KVEC)) { \ - const struct kvec *kvec; \ - struct kvec v; \ - iterate_kvec(i, n, v, kvec, skip, (K)) \ - } else { \ - const struct iovec *iov; \ - struct iovec v; \ - iterate_iovec(i, n, v, iov, skip, (I)) \ + if (likely(n)) { \ + size_t skip = i->iov_offset; \ + if (unlikely(i->type & ITER_BVEC)) { \ + struct bio_vec v; \ + struct bvec_iter __bi; \ + iterate_bvec(i, n, v, __bi, skip, (B)) \ + } else if (unlikely(i->type & ITER_KVEC)) { \ + const struct kvec *kvec; \ + struct kvec v; \ + iterate_kvec(i, n, v, kvec, skip, (K)) \ + } else { \ + const struct iovec *iov; \ + struct iovec v; \ + iterate_iovec(i, n, v, iov, skip, (I)) \ + } \ } \ } @@ -576,7 +578,7 @@ bool copy_from_iter_full(void *addr, size_t bytes, struct iov_iter *i) WARN_ON(1); return false; } - if (unlikely(i->count < bytes)) \ + if (unlikely(i->count < bytes)) return false; iterate_all_kinds(i, bytes, v, ({ @@ -620,7 +622,7 @@ bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i) WARN_ON(1); return false; } - if (unlikely(i->count < bytes)) \ + if (unlikely(i->count < bytes)) return false; iterate_all_kinds(i, bytes, v, ({ if (__copy_from_user_nocache((to += v.iov_len) - v.iov_len, @@ -837,11 +839,8 @@ unsigned long iov_iter_alignment(const struct iov_iter *i) unsigned long res = 0; size_t size = i->count; - if (!size) - return 0; - if (unlikely(i->type & ITER_PIPE)) { - if (i->iov_offset && allocated(&i->pipe->bufs[i->idx])) + if (size && i->iov_offset && allocated(&i->pipe->bufs[i->idx])) return size | i->iov_offset; return size; } @@ -856,10 +855,8 @@ EXPORT_SYMBOL(iov_iter_alignment); unsigned long iov_iter_gap_alignment(const struct iov_iter *i) { - unsigned long res = 0; + unsigned long res = 0; size_t size = i->count; - if (!size) - return 0; if (unlikely(i->type & ITER_PIPE)) { WARN_ON(1); @@ -874,7 +871,7 @@ unsigned long iov_iter_gap_alignment(const struct iov_iter *i) (res |= (!res ? 0 : (unsigned long)v.iov_base) | (size != v.iov_len ? size : 0)) ); - return res; + return res; } EXPORT_SYMBOL(iov_iter_gap_alignment); @@ -908,6 +905,9 @@ static ssize_t pipe_get_pages(struct iov_iter *i, size_t capacity; int idx; + if (!maxsize) + return 0; + if (!sanity(i)) return -EFAULT; @@ -926,9 +926,6 @@ ssize_t iov_iter_get_pages(struct iov_iter *i, if (maxsize > i->count) maxsize = i->count; - if (!maxsize) - return 0; - if (unlikely(i->type & ITER_PIPE)) return pipe_get_pages(i, pages, maxsize, maxpages, start); iterate_all_kinds(i, maxsize, v, ({ @@ -975,6 +972,9 @@ static ssize_t pipe_get_pages_alloc(struct iov_iter *i, int idx; int npages; + if (!maxsize) + return 0; + if (!sanity(i)) return -EFAULT; @@ -1006,9 +1006,6 @@ ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, if (maxsize > i->count) maxsize = i->count; - if (!maxsize) - return 0; - if (unlikely(i->type & ITER_PIPE)) return pipe_get_pages_alloc(i, pages, maxsize, start); iterate_all_kinds(i, maxsize, v, ({ |