um: Remove legacy network transport infrastructure

All legacy network transports have been removed. Vector transports
provide the same capabilities with significantly higher network
throughput. There is no reason to keep the legacy network transport
infrastructure anymore. Remove it to reduce the maintenance burden.

Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://patch.msgid.link/20250503051710.3286595-4-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 0 insertions, 271 deletions

diff --git a/arch/um/drivers/net_user.c b/arch/um/drivers/net_user.c
deleted file mode 100644
index 4c9576452ab0..000000000000
--- a/arch/um/drivers/net_user.c
+++ /dev/null
@@ -1,271 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- */
-
-#include <stdio.h>
-#include <unistd.h>
-#include <stdarg.h>
-#include <errno.h>
-#include <stddef.h>
-#include <string.h>
-#include <sys/socket.h>
-#include <sys/wait.h>
-#include <net_user.h>
-#include <os.h>
-#include <um_malloc.h>
-
-int tap_open_common(void *dev, char *gate_addr)
-{
-	int tap_addr[4];
-
-	if (gate_addr == NULL)
-		return 0;
-	if (sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
-		  &tap_addr[1], &tap_addr[2], &tap_addr[3]) != 4) {
-		printk(UM_KERN_ERR "Invalid tap IP address - '%s'\n",
-		       gate_addr);
-		return -EINVAL;
-	}
-	return 0;
-}
-
-void tap_check_ips(char *gate_addr, unsigned char *eth_addr)
-{
-	int tap_addr[4];
-
-	if ((gate_addr != NULL) &&
-	    (sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
-		    &tap_addr[1], &tap_addr[2], &tap_addr[3]) == 4) &&
-	    (eth_addr[0] == tap_addr[0]) &&
-	    (eth_addr[1] == tap_addr[1]) &&
-	    (eth_addr[2] == tap_addr[2]) &&
-	    (eth_addr[3] == tap_addr[3])) {
-		printk(UM_KERN_ERR "The tap IP address and the UML eth IP "
-		       "address must be different\n");
-	}
-}
-
-/* Do reliable error handling as this fails frequently enough. */
-void read_output(int fd, char *output, int len)
-{
-	int remain, ret, expected;
-	char c;
-	char *str;
-
-	if (output == NULL) {
-		output = &c;
-		len = sizeof(c);
-	}
-
-	*output = '\0';
-	ret = read(fd, &remain, sizeof(remain));
-
-	if (ret != sizeof(remain)) {
-		if (ret < 0)
-			ret = -errno;
-		expected = sizeof(remain);
-		str = "length";
-		goto err;
-	}
-
-	while (remain != 0) {
-		expected = (remain < len) ? remain : len;
-		ret = read(fd, output, expected);
-		if (ret != expected) {
-			if (ret < 0)
-				ret = -errno;
-			str = "data";
-			goto err;
-		}
-		remain -= ret;
-	}
-
-	return;
-
-err:
-	if (ret < 0)
-		printk(UM_KERN_ERR "read_output - read of %s failed, "
-		       "errno = %d\n", str, -ret);
-	else
-		printk(UM_KERN_ERR "read_output - read of %s failed, read only "
-		       "%d of %d bytes\n", str, ret, expected);
-}
-
-int net_read(int fd, void *buf, int len)
-{
-	int n;
-
-	n = read(fd,  buf,  len);
-
-	if ((n < 0) && (errno == EAGAIN))
-		return 0;
-	else if (n == 0)
-		return -ENOTCONN;
-	return n;
-}
-
-int net_recvfrom(int fd, void *buf, int len)
-{
-	int n;
-
-	CATCH_EINTR(n = recvfrom(fd,  buf,  len, 0, NULL, NULL));
-	if (n < 0) {
-		if (errno == EAGAIN)
-			return 0;
-		return -errno;
-	}
-	else if (n == 0)
-		return -ENOTCONN;
-	return n;
-}
-
-int net_write(int fd, void *buf, int len)
-{
-	int n;
-
-	n = write(fd, buf, len);
-
-	if ((n < 0) && (errno == EAGAIN))
-		return 0;
-	else if (n == 0)
-		return -ENOTCONN;
-	return n;
-}
-
-int net_send(int fd, void *buf, int len)
-{
-	int n;
-
-	CATCH_EINTR(n = send(fd, buf, len, 0));
-	if (n < 0) {
-		if (errno == EAGAIN)
-			return 0;
-		return -errno;
-	}
-	else if (n == 0)
-		return -ENOTCONN;
-	return n;
-}
-
-int net_sendto(int fd, void *buf, int len, void *to, int sock_len)
-{
-	int n;
-
-	CATCH_EINTR(n = sendto(fd, buf, len, 0, (struct sockaddr *) to,
-			       sock_len));
-	if (n < 0) {
-		if (errno == EAGAIN)
-			return 0;
-		return -errno;
-	}
-	else if (n == 0)
-		return -ENOTCONN;
-	return n;
-}
-
-struct change_pre_exec_data {
-	int close_me;
-	int stdout_fd;
-};
-
-static void change_pre_exec(void *arg)
-{
-	struct change_pre_exec_data *data = arg;
-
-	close(data->close_me);
-	dup2(data->stdout_fd, 1);
-}
-
-static int change_tramp(char **argv, char *output, int output_len)
-{
-	int pid, fds[2], err;
-	struct change_pre_exec_data pe_data;
-
-	err = os_pipe(fds, 1, 0);
-	if (err < 0) {
-		printk(UM_KERN_ERR "change_tramp - pipe failed, err = %d\n",
-		       -err);
-		return err;
-	}
-	pe_data.close_me = fds[0];
-	pe_data.stdout_fd = fds[1];
-	pid = run_helper(change_pre_exec, &pe_data, argv);
-
-	if (pid > 0)	/* Avoid hang as we won't get data in failure case. */
-		read_output(fds[0], output, output_len);
-
-	close(fds[0]);
-	close(fds[1]);
-
-	if (pid > 0)
-		helper_wait(pid);
-	return pid;
-}
-
-static void change(char *dev, char *what, unsigned char *addr,
-		   unsigned char *netmask)
-{
-	char addr_buf[sizeof("255.255.255.255\0")];
-	char netmask_buf[sizeof("255.255.255.255\0")];
-	char version[sizeof("nnnnn\0")];
-	char *argv[] = { "uml_net", version, what, dev, addr_buf,
-			 netmask_buf, NULL };
-	char *output;
-	int output_len, pid;
-
-	sprintf(version, "%d", UML_NET_VERSION);
-	sprintf(addr_buf, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
-	sprintf(netmask_buf, "%d.%d.%d.%d", netmask[0], netmask[1],
-		netmask[2], netmask[3]);
-
-	output_len = UM_KERN_PAGE_SIZE;
-	output = uml_kmalloc(output_len, UM_GFP_KERNEL);
-	if (output == NULL)
-		printk(UM_KERN_ERR "change : failed to allocate output "
-		       "buffer\n");
-
-	pid = change_tramp(argv, output, output_len);
-	if (pid < 0) {
-		kfree(output);
-		return;
-	}
-
-	if (output != NULL) {
-		printk("%s", output);
-		kfree(output);
-	}
-}
-
-void open_addr(unsigned char *addr, unsigned char *netmask, void *arg)
-{
-	change(arg, "add", addr, netmask);
-}
-
-void close_addr(unsigned char *addr, unsigned char *netmask, void *arg)
-{
-	change(arg, "del", addr, netmask);
-}
-
-char *split_if_spec(char *str, ...)
-{
-	char **arg, *end, *ret = NULL;
-	va_list ap;
-
-	va_start(ap, str);
-	while ((arg = va_arg(ap, char **)) != NULL) {
-		if (*str == '\0')
-			goto out;
-		end = strchr(str, ',');
-		if (end != str)
-			*arg = str;
-		if (end == NULL)
-			goto out;
-		*end++ = '\0';
-		str = end;
-	}
-	ret = str;
-out:
-	va_end(ap);
-	return ret;
-}