[v9,05/20] multi-process: add qio channel function to transmit

Commit Message

Elena Ufimtseva Aug. 27, 2020, 6:12 p.m. UTC

From: Elena Ufimtseva <[e-mail]>

The entire array of the memory regions and file handlers.
Will be used in the next patch.

Signed-off-by: Elena Ufimtseva <[e-mail]>
Signed-off-by: John G Johnson <[e-mail]>
Signed-off-by: Jagannathan Raman <[e-mail]>
Reviewed-by: Stefan Hajnoczi <[e-mail]>
---
 include/io/channel.h | 24 +++++++++++++++++++++++
 io/channel.c         | 45 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+)

Patch

diff --git a/include/io/channel.h b/include/io/channel.h
index d4557f0930..c2e3eaeafc 100644
--- a/include/io/channel.h
+++ b/include/io/channel.h
@@ -779,5 +779,29 @@  void qio_channel_set_aio_fd_handler(QIOChannel *ioc,
                                     IOHandler *io_read,
                                     IOHandler *io_write,
                                     void *opaque);
+/**
+ * qio_channel_writev_full_all:
+ * @ioc: the channel object
+ * @iov: the array of memory regions to write data from
+ * @niov: the length of the @iov array
+ * @fds: an array of file handles to send
+ * @nfds: number of file handles in @fds
+ * @errp: pointer to a NULL-initialized error object
+ *
+ *
+ * Behaves like qio_channel_writev_full but will attempt
+ * to send all data passed (file handles and memory regions).
+ * The function will wait for all requested data
+ * to be written, yielding from the current coroutine
+ * if required.
+ *
+ * Returns: 0 if all bytes were written, or -1 on error
+ */
+
+int qio_channel_writev_full_all(QIOChannel *ioc,
+                           const struct iovec *iov,
+                           size_t niov,
+                           int *fds, size_t nfds,
+                           Error **errp);
 
 #endif /* QIO_CHANNEL_H */
diff --git a/io/channel.c b/io/channel.c
index e4376eb0bc..22c10c5ccc 100644
--- a/io/channel.c
+++ b/io/channel.c
@@ -190,6 +190,51 @@  int qio_channel_writev_all(QIOChannel *ioc,
     return ret;
 }
 
+int qio_channel_writev_full_all(QIOChannel *ioc,
+                                const struct iovec *iov,
+                                size_t niov,
+                                int *fds, size_t nfds,
+                                Error **errp)
+{
+    int ret = -1;
+    struct iovec *local_iov = g_new(struct iovec, niov);
+    struct iovec *local_iov_head = local_iov;
+    unsigned int nlocal_iov = niov;
+
+    nlocal_iov = iov_copy(local_iov, nlocal_iov,
+                          iov, niov,
+                          0, iov_size(iov, niov));
+
+    while (nlocal_iov > 0) {
+        ssize_t len;
+        len = qio_channel_writev_full(ioc, local_iov, nlocal_iov, fds,
+                                      nfds, errp);
+        if (len == QIO_CHANNEL_ERR_BLOCK) {
+            if (qemu_in_coroutine()) {
+                qio_channel_yield(ioc, G_IO_OUT);
+            } else {
+                qio_channel_wait(ioc, G_IO_OUT);
+            }
+            continue;
+        }
+        if (len < 0) {
+            goto cleanup;
+        }
+
+        iov_discard_front(&local_iov, &nlocal_iov, len);
+
+        if (len > 0) {
+            fds = NULL;
+            nfds = 0;
+        }
+    }
+
+    ret = 0;
+ cleanup:
+    g_free(local_iov_head);
+    return ret;
+}
+
 ssize_t qio_channel_readv(QIOChannel *ioc,
                           const struct iovec *iov,
                           size_t niov,