@@ -75,6 +75,11 @@ int qemu_fclose(QEMUFile *f);
int64_t qemu_ftell(QEMUFile *f);
void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size);
void qemu_put_byte(QEMUFile *f, int v);
+/*
+ * put_buffer without copying the buffer.
+ * The buffer should be available till it is sent.
+ */
+void qemu_put_buffer_no_copy(QEMUFile *f, const uint8_t *buf, int size);
static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v)
{
@@ -619,6 +619,22 @@ void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
{
int l;
+ while (size > 0) {
+ l = IO_BUF_SIZE - f->buf_index;
+ if (l > size) {
+ l = size;
+ }
+ memcpy(f->buf + f->buf_index, buf, l);
+ f->buf_index += l;
+ f->is_write = 1;
+ qemu_put_buffer_no_copy(f, f->buf + (f->buf_index - l), l);
+ buf += l;
+ size -= l;
+ }
+}
+
+void qemu_put_buffer_no_copy(QEMUFile *f, const uint8_t *buf, int size)
+{
if (f->last_error) {
return;
}
@@ -629,24 +645,14 @@ void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
abort();
}
- while (size > 0) {
- l = IO_BUF_SIZE - f->buf_index;
- if (l > size)
- l = size;
- memcpy(f->buf + f->buf_index, buf, l);
- f->iov[f->iovcnt].iov_base = f->buf + f->buf_index;
- f->iov[f->iovcnt++].iov_len = l;
- f->is_write = 1;
- f->buf_index += l;
- f->bytes_xfer += l;
- buf += l;
- size -= l;
- if (f->buf_index >= IO_BUF_SIZE || f->iovcnt >= MAX_IOV_SIZE) {
- qemu_fflush(f);
- if (qemu_file_get_error(f)) {
- break;
- }
- }
+ f->iov[f->iovcnt].iov_base = (uint8_t *)buf;
+ f->iov[f->iovcnt++].iov_len = size;
+
+ f->is_write = 1;
+ f->bytes_xfer += size;
+
+ if (f->buf_index >= IO_BUF_SIZE || f->iovcnt >= MAX_IOV_SIZE) {
+ qemu_fflush(f);
}
}
This allow us to add a buffer to the iovec to send without copying it into the static buffer. Signed-off-by: Orit Wasserman <owasserm@redhat.com> --- include/migration/qemu-file.h | 5 +++++ savevm.c | 42 ++++++++++++++++++++++++------------------ 2 files changed, 29 insertions(+), 18 deletions(-)