[qemu.git] / io / channel.c

/*
 * QEMU I/O channels
 *
 * Copyright (c) 2015 Red Hat, Inc.
 *
 * 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.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "qemu/osdep.h"
#include "io/channel.h"
#include "qapi/error.h"
#include "qemu/main-loop.h"
#include "qemu/iov.h"

bool qio_channel_has_feature(QIOChannel *ioc,
                             QIOChannelFeature feature)
{
    return ioc->features & (1 << feature);
}


void qio_channel_set_feature(QIOChannel *ioc,
                             QIOChannelFeature feature)
{
    ioc->features |= (1 << feature);
}


void qio_channel_set_name(QIOChannel *ioc,
                          const char *name)
{
    g_free(ioc->name);
    ioc->name = g_strdup(name);
}


ssize_t qio_channel_readv_full(QIOChannel *ioc,
                               const struct iovec *iov,
                               size_t niov,
                               int **fds,
                               size_t *nfds,
                               Error **errp)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);

    if ((fds || nfds) &&
        !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
        error_setg_errno(errp, EINVAL,
                         "Channel does not support file descriptor passing");
        return -1;
    }

    return klass->io_readv(ioc, iov, niov, fds, nfds, errp);
}


ssize_t qio_channel_writev_full(QIOChannel *ioc,
                                const struct iovec *iov,
                                size_t niov,
                                int *fds,
                                size_t nfds,
                                Error **errp)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);

    if ((fds || nfds) &&
        !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
        error_setg_errno(errp, EINVAL,
                         "Channel does not support file descriptor passing");
        return -1;
    }

    return klass->io_writev(ioc, iov, niov, fds, nfds, errp);
}


int qio_channel_readv_all_eof(QIOChannel *ioc,
                              const struct iovec *iov,
                              size_t niov,
                              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;
    bool partial = false;

    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_readv(ioc, local_iov, nlocal_iov, errp);
        if (len == QIO_CHANNEL_ERR_BLOCK) {
            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) {
            if (partial) {
                error_setg(errp,
                           "Unexpected end-of-file before all bytes were read");
            } else {
                ret = 0;
            }
            goto cleanup;
        }

        partial = true;
        iov_discard_front(&local_iov, &nlocal_iov, len);
    }

    ret = 1;

 cleanup:
    g_free(local_iov_head);
    return ret;
}

int qio_channel_readv_all(QIOChannel *ioc,
                          const struct iovec *iov,
                          size_t niov,
                          Error **errp)
{
    int ret = qio_channel_readv_all_eof(ioc, iov, niov, errp);

    if (ret == 0) {
        ret = -1;
        error_setg(errp,
                   "Unexpected end-of-file before all bytes were read");
    } else if (ret == 1) {
        ret = 0;
    }
    return ret;
}

int qio_channel_writev_all(QIOChannel *ioc,
                           const struct iovec *iov,
                           size_t niov,
                           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(ioc, local_iov, nlocal_iov, 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);
    }

    ret = 0;
 cleanup:
    g_free(local_iov_head);
    return ret;
}

ssize_t qio_channel_readv(QIOChannel *ioc,
                          const struct iovec *iov,
                          size_t niov,
                          Error **errp)
{
    return qio_channel_readv_full(ioc, iov, niov, NULL, NULL, errp);
}


ssize_t qio_channel_writev(QIOChannel *ioc,
                           const struct iovec *iov,
                           size_t niov,
                           Error **errp)
{
    return qio_channel_writev_full(ioc, iov, niov, NULL, 0, errp);
}


ssize_t qio_channel_read(QIOChannel *ioc,
                         char *buf,
                         size_t buflen,
                         Error **errp)
{
    struct iovec iov = { .iov_base = buf, .iov_len = buflen };
    return qio_channel_readv_full(ioc, &iov, 1, NULL, NULL, errp);
}


ssize_t qio_channel_write(QIOChannel *ioc,
                          const char *buf,
                          size_t buflen,
                          Error **errp)
{
    struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
    return qio_channel_writev_full(ioc, &iov, 1, NULL, 0, errp);
}


int 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 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)
{
    struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
    return qio_channel_writev_all(ioc, &iov, 1, errp);
}


int qio_channel_set_blocking(QIOChannel *ioc,
                              bool enabled,
                              Error **errp)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
    return klass->io_set_blocking(ioc, enabled, errp);
}


int qio_channel_close(QIOChannel *ioc,
                      Error **errp)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
    return klass->io_close(ioc, errp);
}


GSource *qio_channel_create_watch(QIOChannel *ioc,
                                  GIOCondition condition)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
    GSource *ret = klass->io_create_watch(ioc, condition);

    if (ioc->name) {
        g_source_set_name(ret, ioc->name);
    }

    return ret;
}


void qio_channel_set_aio_fd_handler(QIOChannel *ioc,
                                    AioContext *ctx,
                                    IOHandler *io_read,
                                    IOHandler *io_write,
                                    void *opaque)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);

    klass->io_set_aio_fd_handler(ioc, ctx, io_read, io_write, opaque);
}

guint qio_channel_add_watch_full(QIOChannel *ioc,
                                 GIOCondition condition,
                                 QIOChannelFunc func,
                                 gpointer user_data,
                                 GDestroyNotify notify,
                                 GMainContext *context)
{
    GSource *source;
    guint id;

    source = qio_channel_create_watch(ioc, condition);

    g_source_set_callback(source, (GSourceFunc)func, user_data, notify);

    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,
                         Error **errp)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);

    if (!klass->io_shutdown) {
        error_setg(errp, "Data path shutdown not supported");
        return -1;
    }

    return klass->io_shutdown(ioc, how, errp);
}


void qio_channel_set_delay(QIOChannel *ioc,
                           bool enabled)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);

    if (klass->io_set_delay) {
        klass->io_set_delay(ioc, enabled);
    }
}


void qio_channel_set_cork(QIOChannel *ioc,
                          bool enabled)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);

    if (klass->io_set_cork) {
        klass->io_set_cork(ioc, enabled);
    }
}


off_t qio_channel_io_seek(QIOChannel *ioc,
                          off_t offset,
                          int whence,
                          Error **errp)
{
    QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);

    if (!klass->io_seek) {
        error_setg(errp, "Channel does not support random access");
        return -1;
    }

    return klass->io_seek(ioc, offset, whence, 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);
    aio_co_wake(co);
}

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);
    aio_co_wake(co);
}

static void qio_channel_set_aio_fd_handlers(QIOChannel *ioc)
{
    IOHandler *rd_handler = NULL, *wr_handler = NULL;
    AioContext *ctx;

    if (ioc->read_coroutine) {
        rd_handler = qio_channel_restart_read;
    }
    if (ioc->write_coroutine) {
        wr_handler = qio_channel_restart_write;
    }

    ctx = ioc->ctx ? ioc->ctx : iohandler_get_aio_context();
    qio_channel_set_aio_fd_handler(ioc, ctx, rd_handler, wr_handler, ioc);
}

void qio_channel_attach_aio_context(QIOChannel *ioc,
                                    AioContext *ctx)
{
    assert(!ioc->read_coroutine);
    assert(!ioc->write_coroutine);
    ioc->ctx = ctx;
}

void qio_channel_detach_aio_context(QIOChannel *ioc)
{
    ioc->read_coroutine = NULL;
    ioc->write_coroutine = NULL;
    qio_channel_set_aio_fd_handlers(ioc);
    ioc->ctx = NULL;
}

void coroutine_fn qio_channel_yield(QIOChannel *ioc,
                                    GIOCondition condition)
{
    assert(qemu_in_coroutine());
    if (condition == G_IO_IN) {
        assert(!ioc->read_coroutine);
        ioc->read_coroutine = qemu_coroutine_self();
    } else if (condition == G_IO_OUT) {
        assert(!ioc->write_coroutine);
        ioc->write_coroutine = qemu_coroutine_self();
    } else {
        abort();
    }
    qio_channel_set_aio_fd_handlers(ioc);
    qemu_coroutine_yield();
}


static gboolean qio_channel_wait_complete(QIOChannel *ioc,
                                          GIOCondition condition,
                                          gpointer opaque)
{
    GMainLoop *loop = opaque;

    g_main_loop_quit(loop);
    return FALSE;
}


void qio_channel_wait(QIOChannel *ioc,
                      GIOCondition condition)
{
    GMainContext *ctxt = g_main_context_new();
    GMainLoop *loop = g_main_loop_new(ctxt, TRUE);
    GSource *source;

    source = qio_channel_create_watch(ioc, condition);

    g_source_set_callback(source,
                          (GSourceFunc)qio_channel_wait_complete,
                          loop,
                          NULL);

    g_source_attach(source, ctxt);

    g_main_loop_run(loop);

    g_source_unref(source);
    g_main_loop_unref(loop);
    g_main_context_unref(ctxt);
}


static void qio_channel_finalize(Object *obj)
{
    QIOChannel *ioc = QIO_CHANNEL(obj);

    g_free(ioc->name);

#ifdef _WIN32
    if (ioc->event) {
        CloseHandle(ioc->event);
    }
#endif
}

static const TypeInfo qio_channel_info = {
    .parent = TYPE_OBJECT,
    .name = TYPE_QIO_CHANNEL,
    .instance_size = sizeof(QIOChannel),
    .instance_finalize = qio_channel_finalize,
    .abstract = true,
    .class_size = sizeof(QIOChannelClass),
};


static void qio_channel_register_types(void)
{
    type_register_static(&qio_channel_info);
}


type_init(qio_channel_register_types);
Commit	Line	Data
666a3af9 DB	1	/*
	2	* QEMU I/O channels
	3	*
	4	* Copyright (c) 2015 Red Hat, Inc.
	5	*
	6	* This library is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU Lesser General Public
	8	* License as published by the Free Software Foundation; either
	9	* version 2 of the License, or (at your option) any later version.
	10	*
	11	* This library is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* Lesser General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU Lesser General Public
	17	* License along with this library; if not, see <http://www.gnu.org/licenses/>.
	18	*
	19	*/
	20
cae9fc56	21	#include "qemu/osdep.h"
666a3af9	22	#include "io/channel.h"
da34e65c	23	#include "qapi/error.h"
c4c497d2	24	#include "qemu/main-loop.h"
d4622e55	25	#include "qemu/iov.h"
666a3af9 DB	26
	27	bool qio_channel_has_feature(QIOChannel *ioc,
	28	QIOChannelFeature feature)
	29	{
	30	return ioc->features & (1 << feature);
	31	}
	32
	33
d8d3c7cc FF	34	void qio_channel_set_feature(QIOChannel *ioc,
	35	QIOChannelFeature feature)
	36	{
	37	ioc->features \|= (1 << feature);
	38	}
	39
	40
20f4aa26 DB	41	void qio_channel_set_name(QIOChannel *ioc,
	42	const char *name)
	43	{
	44	g_free(ioc->name);
	45	ioc->name = g_strdup(name);
	46	}
	47
	48
666a3af9 DB	49	ssize_t qio_channel_readv_full(QIOChannel *ioc,
	50	const struct iovec *iov,
	51	size_t niov,
	52	int **fds,
	53	size_t *nfds,
	54	Error **errp)
	55	{
	56	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	57
	58	if ((fds \|\| nfds) &&
e413ae0c	59	!qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
666a3af9 DB	60	error_setg_errno(errp, EINVAL,
	61	"Channel does not support file descriptor passing");
	62	return -1;
	63	}
	64
	65	return klass->io_readv(ioc, iov, niov, fds, nfds, errp);
	66	}
	67
	68
	69	ssize_t qio_channel_writev_full(QIOChannel *ioc,
	70	const struct iovec *iov,
	71	size_t niov,
	72	int *fds,
	73	size_t nfds,
	74	Error **errp)
	75	{
	76	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	77
	78	if ((fds \|\| nfds) &&
e413ae0c	79	!qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
666a3af9 DB	80	error_setg_errno(errp, EINVAL,
	81	"Channel does not support file descriptor passing");
	82	return -1;
	83	}
	84
	85	return klass->io_writev(ioc, iov, niov, fds, nfds, errp);
	86	}
	87
	88
e8ffaa31 EB	89	int qio_channel_readv_all_eof(QIOChannel *ioc,
	90	const struct iovec *iov,
	91	size_t niov,
	92	Error **errp)
d4622e55 DB	93	{
	94	int ret = -1;
	95	struct iovec *local_iov = g_new(struct iovec, niov);
	96	struct iovec *local_iov_head = local_iov;
	97	unsigned int nlocal_iov = niov;
e8ffaa31	98	bool partial = false;
d4622e55 DB	99
	100	nlocal_iov = iov_copy(local_iov, nlocal_iov,
	101	iov, niov,
	102	0, iov_size(iov, niov));
	103
	104	while (nlocal_iov > 0) {
	105	ssize_t len;
	106	len = qio_channel_readv(ioc, local_iov, nlocal_iov, errp);
	107	if (len == QIO_CHANNEL_ERR_BLOCK) {
9ffb8270 EB	108	if (qemu_in_coroutine()) {
	109	qio_channel_yield(ioc, G_IO_IN);
	110	} else {
	111	qio_channel_wait(ioc, G_IO_IN);
	112	}
d4622e55 DB	113	continue;
	114	} else if (len < 0) {
	115	goto cleanup;
	116	} else if (len == 0) {
e8ffaa31 EB	117	if (partial) {
	118	error_setg(errp,
	119	"Unexpected end-of-file before all bytes were read");
	120	} else {
	121	ret = 0;
	122	}
d4622e55 DB	123	goto cleanup;
	124	}
	125
e8ffaa31	126	partial = true;
d4622e55 DB	127	iov_discard_front(&local_iov, &nlocal_iov, len);
	128	}
	129
e8ffaa31	130	ret = 1;
d4622e55 DB	131
	132	cleanup:
	133	g_free(local_iov_head);
	134	return ret;
	135	}
	136
e8ffaa31 EB	137	int qio_channel_readv_all(QIOChannel *ioc,
	138	const struct iovec *iov,
	139	size_t niov,
	140	Error **errp)
	141	{
	142	int ret = qio_channel_readv_all_eof(ioc, iov, niov, errp);
	143
	144	if (ret == 0) {
	145	ret = -1;
	146	error_setg(errp,
	147	"Unexpected end-of-file before all bytes were read");
	148	} else if (ret == 1) {
	149	ret = 0;
	150	}
	151	return ret;
	152	}
	153
d4622e55 DB	154	int qio_channel_writev_all(QIOChannel *ioc,
	155	const struct iovec *iov,
	156	size_t niov,
	157	Error **errp)
	158	{
	159	int ret = -1;
	160	struct iovec *local_iov = g_new(struct iovec, niov);
	161	struct iovec *local_iov_head = local_iov;
	162	unsigned int nlocal_iov = niov;
	163
	164	nlocal_iov = iov_copy(local_iov, nlocal_iov,
	165	iov, niov,
	166	0, iov_size(iov, niov));
	167
	168	while (nlocal_iov > 0) {
	169	ssize_t len;
	170	len = qio_channel_writev(ioc, local_iov, nlocal_iov, errp);
	171	if (len == QIO_CHANNEL_ERR_BLOCK) {
9ffb8270 EB	172	if (qemu_in_coroutine()) {
	173	qio_channel_yield(ioc, G_IO_OUT);
	174	} else {
	175	qio_channel_wait(ioc, G_IO_OUT);
	176	}
d4622e55 DB	177	continue;
	178	}
	179	if (len < 0) {
	180	goto cleanup;
	181	}
	182
	183	iov_discard_front(&local_iov, &nlocal_iov, len);
	184	}
	185
	186	ret = 0;
	187	cleanup:
	188	g_free(local_iov_head);
	189	return ret;
	190	}
	191
666a3af9 DB	192	ssize_t qio_channel_readv(QIOChannel *ioc,
	193	const struct iovec *iov,
	194	size_t niov,
	195	Error **errp)
	196	{
	197	return qio_channel_readv_full(ioc, iov, niov, NULL, NULL, errp);
	198	}
	199
	200
	201	ssize_t qio_channel_writev(QIOChannel *ioc,
	202	const struct iovec *iov,
	203	size_t niov,
	204	Error **errp)
	205	{
	206	return qio_channel_writev_full(ioc, iov, niov, NULL, 0, errp);
	207	}
	208
	209
	210	ssize_t qio_channel_read(QIOChannel *ioc,
	211	char *buf,
	212	size_t buflen,
	213	Error **errp)
	214	{
	215	struct iovec iov = { .iov_base = buf, .iov_len = buflen };
	216	return qio_channel_readv_full(ioc, &iov, 1, NULL, NULL, errp);
	217	}
	218
	219
	220	ssize_t qio_channel_write(QIOChannel *ioc,
	221	const char *buf,
	222	size_t buflen,
	223	Error **errp)
	224	{
	225	struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
	226	return qio_channel_writev_full(ioc, &iov, 1, NULL, 0, errp);
	227	}
	228
	229
e8ffaa31 EB	230	int qio_channel_read_all_eof(QIOChannel *ioc,
	231	char *buf,
	232	size_t buflen,
	233	Error **errp)
	234	{
	235	struct iovec iov = { .iov_base = buf, .iov_len = buflen };
	236	return qio_channel_readv_all_eof(ioc, &iov, 1, errp);
	237	}
	238
	239
d4622e55 DB	240	int qio_channel_read_all(QIOChannel *ioc,
	241	char *buf,
	242	size_t buflen,
	243	Error **errp)
	244	{
	245	struct iovec iov = { .iov_base = buf, .iov_len = buflen };
	246	return qio_channel_readv_all(ioc, &iov, 1, errp);
	247	}
	248
	249
	250	int qio_channel_write_all(QIOChannel *ioc,
	251	const char *buf,
	252	size_t buflen,
	253	Error **errp)
	254	{
	255	struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
	256	return qio_channel_writev_all(ioc, &iov, 1, errp);
	257	}
	258
	259
666a3af9 DB	260	int qio_channel_set_blocking(QIOChannel *ioc,
	261	bool enabled,
	262	Error **errp)
	263	{
	264	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	265	return klass->io_set_blocking(ioc, enabled, errp);
	266	}
	267
	268
	269	int qio_channel_close(QIOChannel *ioc,
	270	Error **errp)
	271	{
	272	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	273	return klass->io_close(ioc, errp);
	274	}
	275
	276
	277	GSource qio_channel_create_watch(QIOChannel ioc,
	278	GIOCondition condition)
	279	{
	280	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
20f4aa26 DB	281	GSource *ret = klass->io_create_watch(ioc, condition);
	282
	283	if (ioc->name) {
	284	g_source_set_name(ret, ioc->name);
	285	}
	286
	287	return ret;
666a3af9 DB	288	}
	289
	290
bf88c124 PB	291	void qio_channel_set_aio_fd_handler(QIOChannel *ioc,
	292	AioContext *ctx,
	293	IOHandler *io_read,
	294	IOHandler *io_write,
	295	void *opaque)
	296	{
	297	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	298
	299	klass->io_set_aio_fd_handler(ioc, ctx, io_read, io_write, opaque);
	300	}
	301
315409c7 PX	302	guint qio_channel_add_watch_full(QIOChannel *ioc,
	303	GIOCondition condition,
	304	QIOChannelFunc func,
	305	gpointer user_data,
	306	GDestroyNotify notify,
	307	GMainContext *context)
666a3af9 DB	308	{
	309	GSource *source;
	310	guint id;
	311
	312	source = qio_channel_create_watch(ioc, condition);
	313
	314	g_source_set_callback(source, (GSourceFunc)func, user_data, notify);
	315
315409c7	316	id = g_source_attach(source, context);
666a3af9 DB	317	g_source_unref(source);
	318
	319	return id;
	320	}
	321
315409c7 PX	322	guint qio_channel_add_watch(QIOChannel *ioc,
	323	GIOCondition condition,
	324	QIOChannelFunc func,
	325	gpointer user_data,
	326	GDestroyNotify notify)
	327	{
	328	return qio_channel_add_watch_full(ioc, condition, func,
	329	user_data, notify, NULL);
	330	}
	331
	332	GSource qio_channel_add_watch_source(QIOChannel ioc,
	333	GIOCondition condition,
	334	QIOChannelFunc func,
	335	gpointer user_data,
	336	GDestroyNotify notify,
	337	GMainContext *context)
	338	{
	339	GSource *source;
	340	guint id;
	341
	342	id = qio_channel_add_watch_full(ioc, condition, func,
	343	user_data, notify, context);
	344	source = g_main_context_find_source_by_id(context, id);
	345	g_source_ref(source);
	346	return source;
	347	}
	348
666a3af9 DB	349
	350	int qio_channel_shutdown(QIOChannel *ioc,
	351	QIOChannelShutdown how,
	352	Error **errp)
	353	{
	354	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	355
	356	if (!klass->io_shutdown) {
	357	error_setg(errp, "Data path shutdown not supported");
	358	return -1;
	359	}
	360
	361	return klass->io_shutdown(ioc, how, errp);
	362	}
	363
	364
	365	void qio_channel_set_delay(QIOChannel *ioc,
	366	bool enabled)
	367	{
	368	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	369
	370	if (klass->io_set_delay) {
	371	klass->io_set_delay(ioc, enabled);
	372	}
	373	}
	374
	375
	376	void qio_channel_set_cork(QIOChannel *ioc,
	377	bool enabled)
	378	{
	379	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	380
	381	if (klass->io_set_cork) {
	382	klass->io_set_cork(ioc, enabled);
	383	}
	384	}
	385
	386
	387	off_t qio_channel_io_seek(QIOChannel *ioc,
	388	off_t offset,
	389	int whence,
	390	Error **errp)
	391	{
	392	QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
	393
	394	if (!klass->io_seek) {
	395	error_setg(errp, "Channel does not support random access");
	396	return -1;
	397	}
	398
	399	return klass->io_seek(ioc, offset, whence, errp);
	400	}
	401
	402
c4c497d2	403	static void qio_channel_set_aio_fd_handlers(QIOChannel *ioc);
666a3af9	404
c4c497d2 PB	405	static void qio_channel_restart_read(void *opaque)
	406	{
	407	QIOChannel *ioc = opaque;
	408	Coroutine *co = ioc->read_coroutine;
	409
	410	ioc->read_coroutine = NULL;
	411	qio_channel_set_aio_fd_handlers(ioc);
	412	aio_co_wake(co);
	413	}
666a3af9	414
c4c497d2	415	static void qio_channel_restart_write(void *opaque)
666a3af9	416	{
c4c497d2 PB	417	QIOChannel *ioc = opaque;
	418	Coroutine *co = ioc->write_coroutine;
	419
	420	ioc->write_coroutine = NULL;
	421	qio_channel_set_aio_fd_handlers(ioc);
	422	aio_co_wake(co);
666a3af9 DB	423	}
666a3af9 DB	424
c4c497d2 PB	425	static void qio_channel_set_aio_fd_handlers(QIOChannel *ioc)
	426	{
	427	IOHandler rd_handler = NULL, wr_handler = NULL;
	428	AioContext *ctx;
	429
	430	if (ioc->read_coroutine) {
	431	rd_handler = qio_channel_restart_read;
	432	}
	433	if (ioc->write_coroutine) {
	434	wr_handler = qio_channel_restart_write;
	435	}
	436
	437	ctx = ioc->ctx ? ioc->ctx : iohandler_get_aio_context();
	438	qio_channel_set_aio_fd_handler(ioc, ctx, rd_handler, wr_handler, ioc);
	439	}
	440
	441	void qio_channel_attach_aio_context(QIOChannel *ioc,
	442	AioContext *ctx)
	443	{
8f7168b3 PB	444	assert(!ioc->read_coroutine);
8f7168b3 PB	445	assert(!ioc->write_coroutine);
c4c497d2	446	ioc->ctx = ctx;
c4c497d2 PB	447	}
	448
	449	void qio_channel_detach_aio_context(QIOChannel *ioc)
	450	{
	451	ioc->read_coroutine = NULL;
	452	ioc->write_coroutine = NULL;
	453	qio_channel_set_aio_fd_handlers(ioc);
	454	ioc->ctx = NULL;
	455	}
666a3af9 DB	456
	457	void coroutine_fn qio_channel_yield(QIOChannel *ioc,
	458	GIOCondition condition)
	459	{
666a3af9	460	assert(qemu_in_coroutine());
c4c497d2 PB	461	if (condition == G_IO_IN) {
	462	assert(!ioc->read_coroutine);
	463	ioc->read_coroutine = qemu_coroutine_self();
	464	} else if (condition == G_IO_OUT) {
	465	assert(!ioc->write_coroutine);
	466	ioc->write_coroutine = qemu_coroutine_self();
	467	} else {
	468	abort();
	469	}
	470	qio_channel_set_aio_fd_handlers(ioc);
666a3af9 DB	471	qemu_coroutine_yield();
	472	}
	473
	474
	475	static gboolean qio_channel_wait_complete(QIOChannel *ioc,
	476	GIOCondition condition,
	477	gpointer opaque)
	478	{
	479	GMainLoop *loop = opaque;
	480
	481	g_main_loop_quit(loop);
	482	return FALSE;
	483	}
	484
	485
	486	void qio_channel_wait(QIOChannel *ioc,
	487	GIOCondition condition)
	488	{
	489	GMainContext *ctxt = g_main_context_new();
	490	GMainLoop *loop = g_main_loop_new(ctxt, TRUE);
	491	GSource *source;
	492
	493	source = qio_channel_create_watch(ioc, condition);
	494
	495	g_source_set_callback(source,
	496	(GSourceFunc)qio_channel_wait_complete,
	497	loop,
	498	NULL);
	499
	500	g_source_attach(source, ctxt);
	501
	502	g_main_loop_run(loop);
	503
	504	g_source_unref(source);
	505	g_main_loop_unref(loop);
	506	g_main_context_unref(ctxt);
	507	}
	508
	509
a5897205 PB	510	static void qio_channel_finalize(Object *obj)
	511	{
	512	QIOChannel *ioc = QIO_CHANNEL(obj);
	513
20f4aa26 DB	514	g_free(ioc->name);
	515
	516	#ifdef _WIN32
a5897205 PB	517	if (ioc->event) {
	518	CloseHandle(ioc->event);
	519	}
a5897205	520	#endif
20f4aa26	521	}
a5897205	522
666a3af9 DB	523	static const TypeInfo qio_channel_info = {
	524	.parent = TYPE_OBJECT,
	525	.name = TYPE_QIO_CHANNEL,
	526	.instance_size = sizeof(QIOChannel),
a5897205	527	.instance_finalize = qio_channel_finalize,
666a3af9 DB	528	.abstract = true,
	529	.class_size = sizeof(QIOChannelClass),
	530	};
	531
	532
	533	static void qio_channel_register_types(void)
	534	{
	535	type_register_static(&qio_channel_info);
	536	}
	537
	538
	539	type_init(qio_channel_register_types);