diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h index 8b8070fbbf..623c434b15 100644 --- a/include/migration/qemu-file.h +++ b/include/migration/qemu-file.h @@ -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 asynchronously. + */ +void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size); static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v) { diff --git a/savevm.c b/savevm.c index 1d929878ae..406caa90e5 100644 --- a/savevm.c +++ b/savevm.c @@ -633,6 +633,28 @@ static void add_to_iovec(QEMUFile *f, const uint8_t *buf, int size) } } +void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size) +{ + if (f->last_error) { + return; + } + + if (f->is_write == 0 && f->buf_index > 0) { + fprintf(stderr, + "Attempted to write to buffer while read buffer is not empty\n"); + abort(); + } + + add_to_iovec(f, buf, size); + + f->is_write = 1; + f->bytes_xfer += size; + + if (f->buf_index >= IO_BUF_SIZE || f->iovcnt >= MAX_IOV_SIZE) { + qemu_fflush(f); + } +} + void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size) { int l; @@ -652,18 +674,14 @@ void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size) if (l > size) l = size; memcpy(f->buf + f->buf_index, buf, l); - add_to_iovec(f, f->buf + f->buf_index, l); f->is_write = 1; f->buf_index += l; - f->bytes_xfer += l; + qemu_put_buffer_async(f, f->buf + (f->buf_index - l), l); + if (qemu_file_get_error(f)) { + break; + } 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; - } - } } }