v4.19.13 snapshot.
diff --git a/arch/um/drivers/daemon_user.c b/arch/um/drivers/daemon_user.c
new file mode 100644
index 0000000..8813c10
--- /dev/null
+++ b/arch/um/drivers/daemon_user.c
@@ -0,0 +1,193 @@
+/*
+ * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
+ * James Leu (jleu@mindspring.net).
+ * Copyright (C) 2001 by various other people who didn't put their name here.
+ * Licensed under the GPL.
+ */
+
+#include <stdint.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <sys/un.h>
+#include "daemon.h"
+#include <net_user.h>
+#include <os.h>
+#include <um_malloc.h>
+
+enum request_type { REQ_NEW_CONTROL };
+
+#define SWITCH_MAGIC 0xfeedface
+
+struct request_v3 {
+ uint32_t magic;
+ uint32_t version;
+ enum request_type type;
+ struct sockaddr_un sock;
+};
+
+static struct sockaddr_un *new_addr(void *name, int len)
+{
+ struct sockaddr_un *sun;
+
+ sun = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
+ if (sun == NULL) {
+ printk(UM_KERN_ERR "new_addr: allocation of sockaddr_un "
+ "failed\n");
+ return NULL;
+ }
+ sun->sun_family = AF_UNIX;
+ memcpy(sun->sun_path, name, len);
+ return sun;
+}
+
+static int connect_to_switch(struct daemon_data *pri)
+{
+ struct sockaddr_un *ctl_addr = pri->ctl_addr;
+ struct sockaddr_un *local_addr = pri->local_addr;
+ struct sockaddr_un *sun;
+ struct request_v3 req;
+ int fd, n, err;
+
+ pri->control = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (pri->control < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "daemon_open : control socket failed, "
+ "errno = %d\n", -err);
+ return err;
+ }
+
+ if (connect(pri->control, (struct sockaddr *) ctl_addr,
+ sizeof(*ctl_addr)) < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "daemon_open : control connect failed, "
+ "errno = %d\n", -err);
+ goto out;
+ }
+
+ fd = socket(AF_UNIX, SOCK_DGRAM, 0);
+ if (fd < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "daemon_open : data socket failed, "
+ "errno = %d\n", -err);
+ goto out;
+ }
+ if (bind(fd, (struct sockaddr *) local_addr, sizeof(*local_addr)) < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "daemon_open : data bind failed, "
+ "errno = %d\n", -err);
+ goto out_close;
+ }
+
+ sun = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
+ if (sun == NULL) {
+ printk(UM_KERN_ERR "new_addr: allocation of sockaddr_un "
+ "failed\n");
+ err = -ENOMEM;
+ goto out_close;
+ }
+
+ req.magic = SWITCH_MAGIC;
+ req.version = SWITCH_VERSION;
+ req.type = REQ_NEW_CONTROL;
+ req.sock = *local_addr;
+ n = write(pri->control, &req, sizeof(req));
+ if (n != sizeof(req)) {
+ printk(UM_KERN_ERR "daemon_open : control setup request "
+ "failed, err = %d\n", -errno);
+ err = -ENOTCONN;
+ goto out_free;
+ }
+
+ n = read(pri->control, sun, sizeof(*sun));
+ if (n != sizeof(*sun)) {
+ printk(UM_KERN_ERR "daemon_open : read of data socket failed, "
+ "err = %d\n", -errno);
+ err = -ENOTCONN;
+ goto out_free;
+ }
+
+ pri->data_addr = sun;
+ return fd;
+
+ out_free:
+ kfree(sun);
+ out_close:
+ close(fd);
+ out:
+ close(pri->control);
+ return err;
+}
+
+static int daemon_user_init(void *data, void *dev)
+{
+ struct daemon_data *pri = data;
+ struct timeval tv;
+ struct {
+ char zero;
+ int pid;
+ int usecs;
+ } name;
+
+ if (!strcmp(pri->sock_type, "unix"))
+ pri->ctl_addr = new_addr(pri->ctl_sock,
+ strlen(pri->ctl_sock) + 1);
+ name.zero = 0;
+ name.pid = os_getpid();
+ gettimeofday(&tv, NULL);
+ name.usecs = tv.tv_usec;
+ pri->local_addr = new_addr(&name, sizeof(name));
+ pri->dev = dev;
+ pri->fd = connect_to_switch(pri);
+ if (pri->fd < 0) {
+ kfree(pri->local_addr);
+ pri->local_addr = NULL;
+ return pri->fd;
+ }
+
+ return 0;
+}
+
+static int daemon_open(void *data)
+{
+ struct daemon_data *pri = data;
+ return pri->fd;
+}
+
+static void daemon_remove(void *data)
+{
+ struct daemon_data *pri = data;
+
+ close(pri->fd);
+ pri->fd = -1;
+ close(pri->control);
+ pri->control = -1;
+
+ kfree(pri->data_addr);
+ pri->data_addr = NULL;
+ kfree(pri->ctl_addr);
+ pri->ctl_addr = NULL;
+ kfree(pri->local_addr);
+ pri->local_addr = NULL;
+}
+
+int daemon_user_write(int fd, void *buf, int len, struct daemon_data *pri)
+{
+ struct sockaddr_un *data_addr = pri->data_addr;
+
+ return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr));
+}
+
+const struct net_user_info daemon_user_info = {
+ .init = daemon_user_init,
+ .open = daemon_open,
+ .close = NULL,
+ .remove = daemon_remove,
+ .add_address = NULL,
+ .delete_address = NULL,
+ .mtu = ETH_MAX_PACKET,
+ .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
+};