diff options
Diffstat (limited to 'qemu/migration/qemu-file-unix.c')
| -rw-r--r-- | qemu/migration/qemu-file-unix.c | 129 |
1 files changed, 107 insertions, 22 deletions
diff --git a/qemu/migration/qemu-file-unix.c b/qemu/migration/qemu-file-unix.c index bfbc0861a..4474e18ff 100644 --- a/qemu/migration/qemu-file-unix.c +++ b/qemu/migration/qemu-file-unix.c @@ -21,10 +21,12 @@ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ +#include "qemu/osdep.h" #include "qemu-common.h" +#include "qemu/error-report.h" #include "qemu/iov.h" #include "qemu/sockets.h" -#include "block/coroutine.h" +#include "qemu/coroutine.h" #include "migration/qemu-file.h" #include "migration/qemu-file-internal.h" @@ -39,12 +41,42 @@ static ssize_t socket_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, QEMUFileSocket *s = opaque; ssize_t len; ssize_t size = iov_size(iov, iovcnt); + ssize_t offset = 0; + int err; - len = iov_send(s->fd, iov, iovcnt, 0, size); - if (len < size) { - len = -socket_error(); - } - return len; + while (size > 0) { + len = iov_send(s->fd, iov, iovcnt, offset, size); + + if (len > 0) { + size -= len; + offset += len; + } + + if (size > 0) { + if (errno != EAGAIN && errno != EWOULDBLOCK) { + error_report("socket_writev_buffer: Got err=%d for (%zu/%zu)", + errno, (size_t)size, (size_t)len); + /* + * If I've already sent some but only just got the error, I + * could return the amount validly sent so far and wait for the + * next call to report the error, but I'd rather flag the error + * immediately. + */ + return -errno; + } + + /* Emulate blocking */ + GPollFD pfd; + + pfd.fd = s->fd; + pfd.events = G_IO_OUT | G_IO_ERR; + pfd.revents = 0; + TFR(err = g_poll(&pfd, 1, -1 /* no timeout */)); + /* Errors other than EINTR intentionally ignored */ + } + } + + return offset; } static int socket_get_fd(void *opaque) @@ -54,7 +86,8 @@ static int socket_get_fd(void *opaque) return s->fd; } -static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) +static ssize_t socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, + size_t size) { QEMUFileSocket *s = opaque; ssize_t len; @@ -64,15 +97,15 @@ static int socket_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) if (len != -1) { break; } - if (socket_error() == EAGAIN) { + if (errno == EAGAIN) { yield_until_fd_readable(s->fd); - } else if (socket_error() != EINTR) { + } else if (errno != EINTR) { break; } } if (len == -1) { - len = -socket_error(); + len = -errno; } return len; } @@ -96,6 +129,56 @@ static int socket_shutdown(void *opaque, bool rd, bool wr) } } +static int socket_return_close(void *opaque) +{ + QEMUFileSocket *s = opaque; + /* + * Note: We don't close the socket, that should be done by the forward + * path. + */ + g_free(s); + return 0; +} + +static const QEMUFileOps socket_return_read_ops = { + .get_fd = socket_get_fd, + .get_buffer = socket_get_buffer, + .close = socket_return_close, + .shut_down = socket_shutdown, +}; + +static const QEMUFileOps socket_return_write_ops = { + .get_fd = socket_get_fd, + .writev_buffer = socket_writev_buffer, + .close = socket_return_close, + .shut_down = socket_shutdown, +}; + +/* + * Give a QEMUFile* off the same socket but data in the opposite + * direction. + */ +static QEMUFile *socket_get_return_path(void *opaque) +{ + QEMUFileSocket *forward = opaque; + QEMUFileSocket *reverse; + + if (qemu_file_get_error(forward->file)) { + /* If the forward file is in error, don't try and open a return */ + return NULL; + } + + reverse = g_malloc0(sizeof(QEMUFileSocket)); + reverse->fd = forward->fd; + /* I don't think there's a better way to tell which direction 'this' is */ + if (forward->file->ops->get_buffer != NULL) { + /* being called from the read side, so we need to be able to write */ + return qemu_fopen_ops(reverse, &socket_return_write_ops); + } else { + return qemu_fopen_ops(reverse, &socket_return_read_ops); + } +} + static ssize_t unix_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, int64_t pos) { @@ -138,7 +221,8 @@ static ssize_t unix_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, return total; } -static int unix_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) +static ssize_t unix_get_buffer(void *opaque, uint8_t *buf, int64_t pos, + size_t size) { QEMUFileSocket *s = opaque; ssize_t len; @@ -192,7 +276,7 @@ QEMUFile *qemu_fdopen(int fd, const char *mode) return NULL; } - s = g_malloc0(sizeof(QEMUFileSocket)); + s = g_new0(QEMUFileSocket, 1); s->fd = fd; if (mode[0] == 'r') { @@ -204,18 +288,19 @@ QEMUFile *qemu_fdopen(int fd, const char *mode) } static const QEMUFileOps socket_read_ops = { - .get_fd = socket_get_fd, - .get_buffer = socket_get_buffer, - .close = socket_close, - .shut_down = socket_shutdown - + .get_fd = socket_get_fd, + .get_buffer = socket_get_buffer, + .close = socket_close, + .shut_down = socket_shutdown, + .get_return_path = socket_get_return_path }; static const QEMUFileOps socket_write_ops = { - .get_fd = socket_get_fd, - .writev_buffer = socket_writev_buffer, - .close = socket_close, - .shut_down = socket_shutdown + .get_fd = socket_get_fd, + .writev_buffer = socket_writev_buffer, + .close = socket_close, + .shut_down = socket_shutdown, + .get_return_path = socket_get_return_path }; QEMUFile *qemu_fopen_socket(int fd, const char *mode) @@ -226,7 +311,7 @@ QEMUFile *qemu_fopen_socket(int fd, const char *mode) return NULL; } - s = g_malloc0(sizeof(QEMUFileSocket)); + s = g_new0(QEMUFileSocket, 1); s->fd = fd; if (mode[0] == 'w') { qemu_set_block(s->fd); |