bdrv_pad_request() was the main user of qemu_iovec_init_extended().
HEAD^ has removed that use, so we can remove qemu_iovec_init_extended()
now.
The only remaining user is qemu_iovec_init_slice(), which can easily
inline the small part it really needs.
Note that qemu_iovec_init_extended() offered a memcpy() optimization to
initialize the new I/O vector. qemu_iovec_concat_iov(), which is used
to replace its functionality, does not, but calls qemu_iovec_add() for
every single element. If we decide this optimization was important, we
will need to re-implement it in qemu_iovec_concat_iov(), which might
also benefit its pre-existing users.
Signed-off-by: Hanna Czenczek
---
include/qemu/iov.h | 5 ---
util/iov.c | 79 +++---
2 files changed, 11 insertions(+), 73 deletions(-)
diff --git a/include/qemu/iov.h b/include/qemu/iov.h
index 46fadfb27a..63a1c01965 100644
--- a/include/qemu/iov.h
+++ b/include/qemu/iov.h
@@ -222,11 +222,6 @@ static inline void *qemu_iovec_buf(QEMUIOVector *qiov)
void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint);
void qemu_iovec_init_external(QEMUIOVector *qiov, struct iovec *iov, int niov);
-int qemu_iovec_init_extended(
-QEMUIOVector *qiov,
-void *head_buf, size_t head_len,
-QEMUIOVector *mid_qiov, size_t mid_offset, size_t mid_len,
-void *tail_buf, size_t tail_len);
void qemu_iovec_init_slice(QEMUIOVector *qiov, QEMUIOVector *source,
size_t offset, size_t len);
struct iovec *qemu_iovec_slice(QEMUIOVector *qiov,
diff --git a/util/iov.c b/util/iov.c
index 65a70449da..866fb577f3 100644
--- a/util/iov.c
+++ b/util/iov.c
@@ -416,70 +416,6 @@ int qemu_iovec_subvec_niov(QEMUIOVector *qiov, size_t
offset, size_t len)
return niov;
}
-/*
- * Compile new iovec, combining @head_buf buffer, sub-qiov of @mid_qiov,
- * and @tail_buf buffer into new qiov.
- */
-int qemu_iovec_init_extended(
-QEMUIOVector *qiov,
-void *head_buf, size_t head_len,
-QEMUIOVector *mid_qiov, size_t mid_offset, size_t mid_len,
-void *tail_buf, size_t tail_len)
-{
-size_t mid_head, mid_tail;
-int total_niov, mid_niov = 0;
-struct iovec *p, *mid_iov = NULL;
-
-assert(mid_qiov->niov <= IOV_MAX);
-
-if (SIZE_MAX - head_len < mid_len ||
-SIZE_MAX - head_len - mid_len < tail_len)
-{
-return -EINVAL;
-}
-
-if (mid_len) {
-mid_iov = qemu_iovec_slice(mid_qiov, mid_offset, mid_len,
- &mid_head, &mid_tail, &mid_niov);
-}
-
-total_niov = !!head_len + mid_niov + !!tail_len;
-if (total_niov > IOV_MAX) {
-return -EINVAL;
-}
-
-if (total_niov == 1) {
-qemu_iovec_init_buf(qiov, NULL, 0);
-p = &qiov->local_iov;
-} else {
-qiov->niov = qiov->nalloc = total_niov;
-qiov->size = head_len + mid_len + tail_len;
-p = qiov->iov = g_new(struct iovec, qiov->niov);
-}
-
-if (head_len) {
-p->iov_base = head_buf;
-p->iov_len = head_len;
-p++;
-}
-
-assert(!mid_niov == !mid_len);
-if (mid_niov) {
-memcpy(p, mid_iov, mid_niov * sizeof(*p));
-p[0].iov_base = (uint8_t *)p[0].iov_base + mid_head;
-p[0].iov_len -= mid_head;
-p[mid_niov - 1].iov_len -= mid_tail;
-p += mid_niov;
-}
-
-if (tail_len) {
-p->iov_base = tail_buf;
-p->iov_len = tail_len;
-}
-
-return 0;
-}
-
/*
* Check if the contents of subrange of qiov data is all zeroes.
*/
@@ -511,14 +447,21 @@ bool qemu_iovec_is_zero(QEMUIOVector *qiov, size_t
offset, size_t bytes)
void qemu_iovec_init_slice(QEMUIOVector *qiov, QEMUIOVector *source,
size_t offset, size_t len)
{
-int ret;
+struct iovec *slice_iov;
+int slice_niov;
+size_t slice_head, slice_tail;
assert(source->size >= len);
assert(source->size - len >= offset);
-/* We shrink the request, so we can't overflow neither size_t nor MAX_IOV
*/
-ret = qemu_iovec_init_extended(qiov, NULL, 0, source, offset, len, NULL,
0);
-assert(ret == 0);
+slice_iov = qemu_iovec_slice(source, offset, len,
+ &slice_head, &slice_tail, &slice_niov);
+if (slice_niov == 1) {
+qemu_iovec_init_buf(qiov, slice_iov[0].iov_base + slice_head, len);
+} else {
+qemu_iovec_init(qiov, slice_niov);
+qemu_iovec_concat_iov(qiov, slice_iov, slice_niov, slice_head, len);
+}
}
void qemu_iovec_destroy(QEMUIOVector *qiov)
--
2.39.1
