@@ -2959,13 +2959,13 @@ static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs,
// Add the first request to the merged one. If the requests are
// overlapping, drop the last sectors of the first request.
size = (reqs[i].sector - reqs[outidx].sector) << 9;
- qemu_iovec_concat(qiov, reqs[outidx].qiov, size);
+ qemu_iovec_concat(qiov, reqs[outidx].qiov, 0, size);
// We should need to add any zeros between the two requests
assert (reqs[i].sector <= oldreq_last);
// Add the second request
- qemu_iovec_concat(qiov, reqs[i].qiov, reqs[i].qiov->size);
+ qemu_iovec_concat(qiov, reqs[i].qiov, 0, reqs[i].qiov->size);
reqs[outidx].nb_sectors = qiov->size >> 9;
reqs[outidx].qiov = qiov;
@@ -445,7 +445,7 @@ static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num,
index_in_cluster = sector_num & (s->cluster_sectors - 1);
qemu_iovec_reset(&hd_qiov);
- qemu_iovec_copy(&hd_qiov, qiov, bytes_done,
+ qemu_iovec_concat(&hd_qiov, qiov, bytes_done,
cur_nr_sectors * 512);
if (!cluster_offset) {
@@ -514,7 +514,7 @@ static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num,
qcow2_encrypt_sectors(s, sector_num, cluster_data,
cluster_data, cur_nr_sectors, 0, &s->aes_decrypt_key);
qemu_iovec_reset(&hd_qiov);
- qemu_iovec_copy(&hd_qiov, qiov, bytes_done,
+ qemu_iovec_concat(&hd_qiov, qiov, bytes_done,
cur_nr_sectors * 512);
qemu_iovec_from_buffer(&hd_qiov, 0, cluster_data,
512 * cur_nr_sectors);
@@ -596,7 +596,7 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
assert((cluster_offset & 511) == 0);
qemu_iovec_reset(&hd_qiov);
- qemu_iovec_copy(&hd_qiov, qiov, bytes_done,
+ qemu_iovec_concat(&hd_qiov, qiov, bytes_done,
cur_nr_sectors * 512);
if (s->crypt_method) {
@@ -1133,7 +1133,7 @@ static void qed_aio_write_alloc(QEDAIOCB *acb, size_t len)
acb->cur_nclusters = qed_bytes_to_clusters(s,
qed_offset_into_cluster(s, acb->cur_pos) + len);
- qemu_iovec_copy(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
+ qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
if (acb->flags & QED_AIOCB_ZERO) {
/* Skip ahead if the clusters are already zero */
@@ -1179,7 +1179,7 @@ static void qed_aio_write_inplace(QEDAIOCB *acb, uint64_t offset, size_t len)
/* Calculate the I/O vector */
acb->cur_cluster = offset;
- qemu_iovec_copy(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
+ qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
/* Do the actual write */
qed_aio_write_main(acb, 0);
@@ -1249,7 +1249,7 @@ static void qed_aio_read_data(void *opaque, int ret,
goto err;
}
- qemu_iovec_copy(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
+ qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
/* Handle zero cluster and backing file reads */
if (ret == QED_CLUSTER_ZERO) {
@@ -171,48 +171,34 @@ void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len)
}
/*
- * Copies iovecs from src to the end of dst. It starts copying after skipping
- * the given number of bytes in src and copies until src is completely copied
- * or the total size of the copied iovec reaches size.The size of the last
- * copied iovec is changed in order to fit the specified total size if it isn't
- * a perfect fit already.
+ * Concatenates (partial) iovecs from src to the end of dst.
+ * It starts copying after skipping `soffset' bytes at the
+ * beginning of src and copies `sbytes' bytes from that point.
+ * The size of the last copied iovec is changed in order to fit the
+ * specified total size if it isn't a perfect fit already.
*/
-void qemu_iovec_copy(QEMUIOVector *dst, QEMUIOVector *src, uint64_t skip,
- size_t size)
+void qemu_iovec_concat(QEMUIOVector *dst,
+ QEMUIOVector *src, size_t soffset, size_t sbytes)
{
int i;
- size_t done;
- void *iov_base;
- uint64_t iov_len;
+ struct iovec *siov = src->iov;
assert(dst->nalloc != -1);
+ assert(src->size >= soffset);
+ assert(src->size - soffset >= sbytes);
- done = 0;
- for (i = 0; (i < src->niov) && (done != size); i++) {
- if (skip >= src->iov[i].iov_len) {
- /* Skip the whole iov */
- skip -= src->iov[i].iov_len;
- continue;
- } else {
- /* Skip only part (or nothing) of the iov */
- iov_base = (uint8_t*) src->iov[i].iov_base + skip;
- iov_len = src->iov[i].iov_len - skip;
- skip = 0;
- }
-
- if (done + iov_len > size) {
- qemu_iovec_add(dst, iov_base, size - done);
- break;
- } else {
- qemu_iovec_add(dst, iov_base, iov_len);
- }
- done += iov_len;
+ /* first skip initial full-sized source elements */
+ for(i = 0; soffset >= siov[i].iov_len; ++i) {
+ soffset -= siov[i].iov_len;
+ }
+ /* skip/copy partial element and copy the rest */
+ while(sbytes) {
+ size_t n = MIN(sbytes, siov[i].iov_len - soffset);
+ qemu_iovec_add(dst, (char*)siov[i].iov_base + soffset, n);
+ sbytes -= n;
+ ++i;
+ soffset = 0;
}
-}
-
-void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t size)
-{
- qemu_iovec_copy(dst, src, 0, size);
}
void qemu_iovec_destroy(QEMUIOVector *qiov)
@@ -1648,7 +1648,7 @@ out:
* with qemu_iovec_destroy().
*/
static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
- uint64_t skip, size_t size,
+ size_t skip, size_t size,
bool is_write)
{
QEMUIOVector elem;
@@ -1665,7 +1665,7 @@ static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
qemu_iovec_init_external(&elem, iov, niov);
qemu_iovec_init(qiov, niov);
- qemu_iovec_copy(qiov, &elem, skip, size);
+ qemu_iovec_concat(qiov, &elem, skip, size);
}
static void v9fs_read(void *opaque)
@@ -1715,7 +1715,7 @@ static void v9fs_read(void *opaque)
qemu_iovec_init(&qiov, qiov_full.niov);
do {
qemu_iovec_reset(&qiov);
- qemu_iovec_copy(&qiov, &qiov_full, count, qiov_full.size - count);
+ qemu_iovec_concat(&qiov, &qiov_full, count, qiov_full.size - count);
if (0) {
print_sg(qiov.iov, qiov.niov);
}
@@ -1970,7 +1970,7 @@ static void v9fs_write(void *opaque)
qemu_iovec_init(&qiov, qiov_full.niov);
do {
qemu_iovec_reset(&qiov);
- qemu_iovec_copy(&qiov, &qiov_full, total, qiov_full.size - total);
+ qemu_iovec_concat(&qiov, &qiov_full, total, qiov_full.size - total);
if (0) {
print_sg(qiov.iov, qiov.niov);
}
@@ -333,9 +333,8 @@ typedef struct QEMUIOVector {
void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint);
void qemu_iovec_init_external(QEMUIOVector *qiov, struct iovec *iov, int niov);
void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len);
-void qemu_iovec_copy(QEMUIOVector *dst, QEMUIOVector *src, uint64_t skip,
- size_t size);
-void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t size);
+void qemu_iovec_concat(QEMUIOVector *dst,
+ QEMUIOVector *src, size_t soffset, size_t sbytes);
void qemu_iovec_destroy(QEMUIOVector *qiov);
void qemu_iovec_reset(QEMUIOVector *qiov);
void qemu_iovec_to_buffer(QEMUIOVector *qiov, void *buf);