]> git.proxmox.com Git - mirror_qemu.git/blobdiff - io/channel.c
target/loongarch: Implement vexth
[mirror_qemu.git] / io / channel.c
index 5e8c2f0a91918ac05f99af3cd2478cbbb8bd9d69..375a130a398d34cbc453c1d0c3b2feb9d55146dd 100644 (file)
@@ -6,7 +6,7 @@
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -22,6 +22,7 @@
 #include "io/channel.h"
 #include "qapi/error.h"
 #include "qemu/main-loop.h"
+#include "qemu/module.h"
 #include "qemu/iov.h"
 
 bool qio_channel_has_feature(QIOChannel *ioc,
@@ -51,6 +52,7 @@ ssize_t qio_channel_readv_full(QIOChannel *ioc,
                                size_t niov,
                                int **fds,
                                size_t *nfds,
+                               int flags,
                                Error **errp)
 {
     QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
@@ -62,7 +64,14 @@ ssize_t qio_channel_readv_full(QIOChannel *ioc,
         return -1;
     }
 
-    return klass->io_readv(ioc, iov, niov, fds, nfds, errp);
+    if ((flags & QIO_CHANNEL_READ_FLAG_MSG_PEEK) &&
+        !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_READ_MSG_PEEK)) {
+        error_setg_errno(errp, EINVAL,
+                         "Channel does not support peek read");
+        return -1;
+    }
+
+    return klass->io_readv(ioc, iov, niov, fds, nfds, flags, errp);
 }
 
 
@@ -71,64 +80,173 @@ ssize_t qio_channel_writev_full(QIOChannel *ioc,
                                 size_t niov,
                                 int *fds,
                                 size_t nfds,
+                                int flags,
                                 Error **errp)
 {
     QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
 
-    if ((fds || nfds) &&
-        !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
+    if (fds || nfds) {
+        if (!qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
+            error_setg_errno(errp, EINVAL,
+                             "Channel does not support file descriptor passing");
+            return -1;
+        }
+        if (flags & QIO_CHANNEL_WRITE_FLAG_ZERO_COPY) {
+            error_setg_errno(errp, EINVAL,
+                             "Zero Copy does not support file descriptor passing");
+            return -1;
+        }
+    }
+
+    if ((flags & QIO_CHANNEL_WRITE_FLAG_ZERO_COPY) &&
+        !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_WRITE_ZERO_COPY)) {
         error_setg_errno(errp, EINVAL,
-                         "Channel does not support file descriptor passing");
+                         "Requested Zero Copy feature is not available");
         return -1;
     }
 
-    return klass->io_writev(ioc, iov, niov, fds, nfds, errp);
+    return klass->io_writev(ioc, iov, niov, fds, nfds, flags, errp);
 }
 
 
+int coroutine_mixed_fn qio_channel_readv_all_eof(QIOChannel *ioc,
+                                                 const struct iovec *iov,
+                                                 size_t niov,
+                                                 Error **errp)
+{
+    return qio_channel_readv_full_all_eof(ioc, iov, niov, NULL, NULL, errp);
+}
+
+int coroutine_mixed_fn qio_channel_readv_all(QIOChannel *ioc,
+                                             const struct iovec *iov,
+                                             size_t niov,
+                                             Error **errp)
+{
+    return qio_channel_readv_full_all(ioc, iov, niov, NULL, NULL, errp);
+}
 
-int qio_channel_readv_all(QIOChannel *ioc,
-                          const struct iovec *iov,
-                          size_t niov,
-                          Error **errp)
+int coroutine_mixed_fn qio_channel_readv_full_all_eof(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;
+    int **local_fds = fds;
+    size_t *local_nfds = nfds;
+    bool partial = false;
+
+    if (nfds) {
+        *nfds = 0;
+    }
+
+    if (fds) {
+        *fds = NULL;
+    }
 
     nlocal_iov = iov_copy(local_iov, nlocal_iov,
                           iov, niov,
                           0, iov_size(iov, niov));
 
-    while (nlocal_iov > 0) {
+    while ((nlocal_iov > 0) || local_fds) {
         ssize_t len;
-        len = qio_channel_readv(ioc, local_iov, nlocal_iov, errp);
+        len = qio_channel_readv_full(ioc, local_iov, nlocal_iov, local_fds,
+                                     local_nfds, 0, errp);
         if (len == QIO_CHANNEL_ERR_BLOCK) {
-            qio_channel_wait(ioc, G_IO_IN);
+            if (qemu_in_coroutine()) {
+                qio_channel_yield(ioc, G_IO_IN);
+            } else {
+                qio_channel_wait(ioc, G_IO_IN);
+            }
             continue;
-        } else if (len < 0) {
-            goto cleanup;
-        } else if (len == 0) {
-            error_setg(errp,
-                       "Unexpected end-of-file before all bytes were read");
+        }
+
+        if (len == 0) {
+            if (local_nfds && *local_nfds) {
+                /*
+                 * Got some FDs, but no data yet. This isn't an EOF
+                 * scenario (yet), so carry on to try to read data
+                 * on next loop iteration
+                 */
+                goto next_iter;
+            } else if (!partial) {
+                /* No fds and no data - EOF before any data read */
+                ret = 0;
+                goto cleanup;
+            } else {
+                len = -1;
+                error_setg(errp,
+                           "Unexpected end-of-file before all data were read");
+                /* Fallthrough into len < 0 handling */
+            }
+        }
+
+        if (len < 0) {
+            /* Close any FDs we previously received */
+            if (nfds && fds) {
+                size_t i;
+                for (i = 0; i < (*nfds); i++) {
+                    close((*fds)[i]);
+                }
+                g_free(*fds);
+                *fds = NULL;
+                *nfds = 0;
+            }
             goto cleanup;
         }
 
-        iov_discard_front(&local_iov, &nlocal_iov, len);
+        if (nlocal_iov) {
+            iov_discard_front(&local_iov, &nlocal_iov, len);
+        }
+
+next_iter:
+        partial = true;
+        local_fds = NULL;
+        local_nfds = NULL;
     }
 
-    ret = 0;
+    ret = 1;
 
  cleanup:
     g_free(local_iov_head);
     return ret;
 }
 
-int qio_channel_writev_all(QIOChannel *ioc,
-                           const struct iovec *iov,
-                           size_t niov,
-                           Error **errp)
+int coroutine_mixed_fn qio_channel_readv_full_all(QIOChannel *ioc,
+                                                  const struct iovec *iov,
+                                                  size_t niov,
+                                                  int **fds, size_t *nfds,
+                                                  Error **errp)
+{
+    int ret = qio_channel_readv_full_all_eof(ioc, iov, niov, fds, nfds, errp);
+
+    if (ret == 0) {
+        error_setg(errp, "Unexpected end-of-file before all data were read");
+        return -1;
+    }
+    if (ret == 1) {
+        return 0;
+    }
+
+    return ret;
+}
+
+int coroutine_mixed_fn qio_channel_writev_all(QIOChannel *ioc,
+                                              const struct iovec *iov,
+                                              size_t niov,
+                                              Error **errp)
+{
+    return qio_channel_writev_full_all(ioc, iov, niov, NULL, 0, 0, errp);
+}
+
+int coroutine_mixed_fn qio_channel_writev_full_all(QIOChannel *ioc,
+                                                   const struct iovec *iov,
+                                                   size_t niov,
+                                                   int *fds, size_t nfds,
+                                                   int flags, Error **errp)
 {
     int ret = -1;
     struct iovec *local_iov = g_new(struct iovec, niov);
@@ -141,9 +259,16 @@ int qio_channel_writev_all(QIOChannel *ioc,
 
     while (nlocal_iov > 0) {
         ssize_t len;
-        len = qio_channel_writev(ioc, local_iov, nlocal_iov, errp);
+
+        len = qio_channel_writev_full(ioc, local_iov, nlocal_iov, fds,
+                                            nfds, flags, errp);
+
         if (len == QIO_CHANNEL_ERR_BLOCK) {
-            qio_channel_wait(ioc, G_IO_OUT);
+            if (qemu_in_coroutine()) {
+                qio_channel_yield(ioc, G_IO_OUT);
+            } else {
+                qio_channel_wait(ioc, G_IO_OUT);
+            }
             continue;
         }
         if (len < 0) {
@@ -151,6 +276,9 @@ int qio_channel_writev_all(QIOChannel *ioc,
         }
 
         iov_discard_front(&local_iov, &nlocal_iov, len);
+
+        fds = NULL;
+        nfds = 0;
     }
 
     ret = 0;
@@ -164,7 +292,7 @@ ssize_t qio_channel_readv(QIOChannel *ioc,
                           size_t niov,
                           Error **errp)
 {
-    return qio_channel_readv_full(ioc, iov, niov, NULL, NULL, errp);
+    return qio_channel_readv_full(ioc, iov, niov, NULL, NULL, 0, errp);
 }
 
 
@@ -173,7 +301,7 @@ ssize_t qio_channel_writev(QIOChannel *ioc,
                            size_t niov,
                            Error **errp)
 {
-    return qio_channel_writev_full(ioc, iov, niov, NULL, 0, errp);
+    return qio_channel_writev_full(ioc, iov, niov, NULL, 0, 0, errp);
 }
 
 
@@ -183,7 +311,7 @@ ssize_t qio_channel_read(QIOChannel *ioc,
                          Error **errp)
 {
     struct iovec iov = { .iov_base = buf, .iov_len = buflen };
-    return qio_channel_readv_full(ioc, &iov, 1, NULL, NULL, errp);
+    return qio_channel_readv_full(ioc, &iov, 1, NULL, NULL, 0, errp);
 }
 
 
@@ -193,24 +321,34 @@ ssize_t qio_channel_write(QIOChannel *ioc,
                           Error **errp)
 {
     struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
-    return qio_channel_writev_full(ioc, &iov, 1, NULL, 0, errp);
+    return qio_channel_writev_full(ioc, &iov, 1, NULL, 0, 0, errp);
 }
 
 
-int qio_channel_read_all(QIOChannel *ioc,
-                         char *buf,
-                         size_t buflen,
-                         Error **errp)
+int coroutine_mixed_fn qio_channel_read_all_eof(QIOChannel *ioc,
+                                                char *buf,
+                                                size_t buflen,
+                                                Error **errp)
+{
+    struct iovec iov = { .iov_base = buf, .iov_len = buflen };
+    return qio_channel_readv_all_eof(ioc, &iov, 1, errp);
+}
+
+
+int coroutine_mixed_fn qio_channel_read_all(QIOChannel *ioc,
+                                            char *buf,
+                                            size_t buflen,
+                                            Error **errp)
 {
     struct iovec iov = { .iov_base = buf, .iov_len = buflen };
     return qio_channel_readv_all(ioc, &iov, 1, errp);
 }
 
 
-int qio_channel_write_all(QIOChannel *ioc,
-                          const char *buf,
-                          size_t buflen,
-                          Error **errp)
+int coroutine_mixed_fn qio_channel_write_all(QIOChannel *ioc,
+                                             const char *buf,
+                                             size_t buflen,
+                                             Error **errp)
 {
     struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
     return qio_channel_writev_all(ioc, &iov, 1, errp);
@@ -259,11 +397,12 @@ void qio_channel_set_aio_fd_handler(QIOChannel *ioc,
     klass->io_set_aio_fd_handler(ioc, ctx, io_read, io_write, opaque);
 }
 
-guint qio_channel_add_watch(QIOChannel *ioc,
-                            GIOCondition condition,
-                            QIOChannelFunc func,
-                            gpointer user_data,
-                            GDestroyNotify notify)
+guint qio_channel_add_watch_full(QIOChannel *ioc,
+                                 GIOCondition condition,
+                                 QIOChannelFunc func,
+                                 gpointer user_data,
+                                 GDestroyNotify notify,
+                                 GMainContext *context)
 {
     GSource *source;
     guint id;
@@ -272,12 +411,39 @@ guint qio_channel_add_watch(QIOChannel *ioc,
 
     g_source_set_callback(source, (GSourceFunc)func, user_data, notify);
 
-    id = g_source_attach(source, NULL);
+    id = g_source_attach(source, context);
     g_source_unref(source);
 
     return id;
 }
 
+guint qio_channel_add_watch(QIOChannel *ioc,
+                            GIOCondition condition,
+                            QIOChannelFunc func,
+                            gpointer user_data,
+                            GDestroyNotify notify)
+{
+    return qio_channel_add_watch_full(ioc, condition, func,
+                                      user_data, notify, NULL);
+}
+
+GSource *qio_channel_add_watch_source(QIOChannel *ioc,
+                                      GIOCondition condition,
+                                      QIOChannelFunc func,
+                                      gpointer user_data,
+                                      GDestroyNotify notify,
+                                      GMainContext *context)
+{
+    GSource *source;
+    guint id;
+
+    id = qio_channel_add_watch_full(ioc, condition, func,
+                                    user_data, notify, context);
+    source = g_main_context_find_source_by_id(context, id);
+    g_source_ref(source);
+    return source;
+}
+
 
 int qio_channel_shutdown(QIOChannel *ioc,
                          QIOChannelShutdown how,
@@ -331,16 +497,28 @@ off_t qio_channel_io_seek(QIOChannel *ioc,
     return klass->io_seek(ioc, offset, whence, errp);
 }
 
+int qio_channel_flush(QIOChannel *ioc,
+                                Error **errp)
+{
+    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
+
+    if (!klass->io_flush ||
+        !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_WRITE_ZERO_COPY)) {
+        return 0;
+    }
+
+    return klass->io_flush(ioc, errp);
+}
 
-static void qio_channel_set_aio_fd_handlers(QIOChannel *ioc);
 
 static void qio_channel_restart_read(void *opaque)
 {
     QIOChannel *ioc = opaque;
     Coroutine *co = ioc->read_coroutine;
 
-    ioc->read_coroutine = NULL;
-    qio_channel_set_aio_fd_handlers(ioc);
+    /* Assert that aio_co_wake() reenters the coroutine directly */
+    assert(qemu_get_current_aio_context() ==
+           qemu_coroutine_get_aio_context(co));
     aio_co_wake(co);
 }
 
@@ -349,8 +527,9 @@ static void qio_channel_restart_write(void *opaque)
     QIOChannel *ioc = opaque;
     Coroutine *co = ioc->write_coroutine;
 
-    ioc->write_coroutine = NULL;
-    qio_channel_set_aio_fd_handlers(ioc);
+    /* Assert that aio_co_wake() reenters the coroutine directly */
+    assert(qemu_get_current_aio_context() ==
+           qemu_coroutine_get_aio_context(co));
     aio_co_wake(co);
 }
 
@@ -401,6 +580,16 @@ void coroutine_fn qio_channel_yield(QIOChannel *ioc,
     }
     qio_channel_set_aio_fd_handlers(ioc);
     qemu_coroutine_yield();
+
+    /* Allow interrupting the operation by reentering the coroutine other than
+     * through the aio_fd_handlers. */
+    if (condition == G_IO_IN && ioc->read_coroutine) {
+        ioc->read_coroutine = NULL;
+        qio_channel_set_aio_fd_handlers(ioc);
+    } else if (condition == G_IO_OUT && ioc->write_coroutine) {
+        ioc->write_coroutine = NULL;
+        qio_channel_set_aio_fd_handlers(ioc);
+    }
 }