v4.19.13 snapshot.
diff --git a/net/decnet/sysctl_net_decnet.c b/net/decnet/sysctl_net_decnet.c
new file mode 100644
index 0000000..55bf64a
--- /dev/null
+++ b/net/decnet/sysctl_net_decnet.c
@@ -0,0 +1,373 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DECnet An implementation of the DECnet protocol suite for the LINUX
+ * operating system. DECnet is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * DECnet sysctl support functions
+ *
+ * Author: Steve Whitehouse <SteveW@ACM.org>
+ *
+ *
+ * Changes:
+ * Steve Whitehouse - C99 changes and default device handling
+ * Steve Whitehouse - Memory buffer settings, like the tcp ones
+ *
+ */
+#include <linux/mm.h>
+#include <linux/sysctl.h>
+#include <linux/fs.h>
+#include <linux/netdevice.h>
+#include <linux/string.h>
+#include <net/neighbour.h>
+#include <net/dst.h>
+#include <net/flow.h>
+
+#include <linux/uaccess.h>
+
+#include <net/dn.h>
+#include <net/dn_dev.h>
+#include <net/dn_route.h>
+
+
+int decnet_debug_level;
+int decnet_time_wait = 30;
+int decnet_dn_count = 1;
+int decnet_di_count = 3;
+int decnet_dr_count = 3;
+int decnet_log_martians = 1;
+int decnet_no_fc_max_cwnd = NSP_MIN_WINDOW;
+
+/* Reasonable defaults, I hope, based on tcp's defaults */
+long sysctl_decnet_mem[3] = { 768 << 3, 1024 << 3, 1536 << 3 };
+int sysctl_decnet_wmem[3] = { 4 * 1024, 16 * 1024, 128 * 1024 };
+int sysctl_decnet_rmem[3] = { 4 * 1024, 87380, 87380 * 2 };
+
+#ifdef CONFIG_SYSCTL
+extern int decnet_dst_gc_interval;
+static int min_decnet_time_wait[] = { 5 };
+static int max_decnet_time_wait[] = { 600 };
+static int min_state_count[] = { 1 };
+static int max_state_count[] = { NSP_MAXRXTSHIFT };
+static int min_decnet_dst_gc_interval[] = { 1 };
+static int max_decnet_dst_gc_interval[] = { 60 };
+static int min_decnet_no_fc_max_cwnd[] = { NSP_MIN_WINDOW };
+static int max_decnet_no_fc_max_cwnd[] = { NSP_MAX_WINDOW };
+static char node_name[7] = "???";
+
+static struct ctl_table_header *dn_table_header = NULL;
+
+/*
+ * ctype.h :-)
+ */
+#define ISNUM(x) (((x) >= '0') && ((x) <= '9'))
+#define ISLOWER(x) (((x) >= 'a') && ((x) <= 'z'))
+#define ISUPPER(x) (((x) >= 'A') && ((x) <= 'Z'))
+#define ISALPHA(x) (ISLOWER(x) || ISUPPER(x))
+#define INVALID_END_CHAR(x) (ISNUM(x) || ISALPHA(x))
+
+static void strip_it(char *str)
+{
+ for(;;) {
+ switch (*str) {
+ case ' ':
+ case '\n':
+ case '\r':
+ case ':':
+ *str = 0;
+ /* Fallthrough */
+ case 0:
+ return;
+ }
+ str++;
+ }
+}
+
+/*
+ * Simple routine to parse an ascii DECnet address
+ * into a network order address.
+ */
+static int parse_addr(__le16 *addr, char *str)
+{
+ __u16 area, node;
+
+ while(*str && !ISNUM(*str)) str++;
+
+ if (*str == 0)
+ return -1;
+
+ area = (*str++ - '0');
+ if (ISNUM(*str)) {
+ area *= 10;
+ area += (*str++ - '0');
+ }
+
+ if (*str++ != '.')
+ return -1;
+
+ if (!ISNUM(*str))
+ return -1;
+
+ node = *str++ - '0';
+ if (ISNUM(*str)) {
+ node *= 10;
+ node += (*str++ - '0');
+ }
+ if (ISNUM(*str)) {
+ node *= 10;
+ node += (*str++ - '0');
+ }
+ if (ISNUM(*str)) {
+ node *= 10;
+ node += (*str++ - '0');
+ }
+
+ if ((node > 1023) || (area > 63))
+ return -1;
+
+ if (INVALID_END_CHAR(*str))
+ return -1;
+
+ *addr = cpu_to_le16((area << 10) | node);
+
+ return 0;
+}
+
+static int dn_node_address_handler(struct ctl_table *table, int write,
+ void __user *buffer,
+ size_t *lenp, loff_t *ppos)
+{
+ char addr[DN_ASCBUF_LEN];
+ size_t len;
+ __le16 dnaddr;
+
+ if (!*lenp || (*ppos && !write)) {
+ *lenp = 0;
+ return 0;
+ }
+
+ if (write) {
+ len = (*lenp < DN_ASCBUF_LEN) ? *lenp : (DN_ASCBUF_LEN-1);
+
+ if (copy_from_user(addr, buffer, len))
+ return -EFAULT;
+
+ addr[len] = 0;
+ strip_it(addr);
+
+ if (parse_addr(&dnaddr, addr))
+ return -EINVAL;
+
+ dn_dev_devices_off();
+
+ decnet_address = dnaddr;
+
+ dn_dev_devices_on();
+
+ *ppos += len;
+
+ return 0;
+ }
+
+ dn_addr2asc(le16_to_cpu(decnet_address), addr);
+ len = strlen(addr);
+ addr[len++] = '\n';
+
+ if (len > *lenp) len = *lenp;
+
+ if (copy_to_user(buffer, addr, len))
+ return -EFAULT;
+
+ *lenp = len;
+ *ppos += len;
+
+ return 0;
+}
+
+static int dn_def_dev_handler(struct ctl_table *table, int write,
+ void __user *buffer,
+ size_t *lenp, loff_t *ppos)
+{
+ size_t len;
+ struct net_device *dev;
+ char devname[17];
+
+ if (!*lenp || (*ppos && !write)) {
+ *lenp = 0;
+ return 0;
+ }
+
+ if (write) {
+ if (*lenp > 16)
+ return -E2BIG;
+
+ if (copy_from_user(devname, buffer, *lenp))
+ return -EFAULT;
+
+ devname[*lenp] = 0;
+ strip_it(devname);
+
+ dev = dev_get_by_name(&init_net, devname);
+ if (dev == NULL)
+ return -ENODEV;
+
+ if (dev->dn_ptr == NULL) {
+ dev_put(dev);
+ return -ENODEV;
+ }
+
+ if (dn_dev_set_default(dev, 1)) {
+ dev_put(dev);
+ return -ENODEV;
+ }
+ *ppos += *lenp;
+
+ return 0;
+ }
+
+ dev = dn_dev_get_default();
+ if (dev == NULL) {
+ *lenp = 0;
+ return 0;
+ }
+
+ strcpy(devname, dev->name);
+ dev_put(dev);
+ len = strlen(devname);
+ devname[len++] = '\n';
+
+ if (len > *lenp) len = *lenp;
+
+ if (copy_to_user(buffer, devname, len))
+ return -EFAULT;
+
+ *lenp = len;
+ *ppos += len;
+
+ return 0;
+}
+
+static struct ctl_table dn_table[] = {
+ {
+ .procname = "node_address",
+ .maxlen = 7,
+ .mode = 0644,
+ .proc_handler = dn_node_address_handler,
+ },
+ {
+ .procname = "node_name",
+ .data = node_name,
+ .maxlen = 7,
+ .mode = 0644,
+ .proc_handler = proc_dostring,
+ },
+ {
+ .procname = "default_device",
+ .maxlen = 16,
+ .mode = 0644,
+ .proc_handler = dn_def_dev_handler,
+ },
+ {
+ .procname = "time_wait",
+ .data = &decnet_time_wait,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &min_decnet_time_wait,
+ .extra2 = &max_decnet_time_wait
+ },
+ {
+ .procname = "dn_count",
+ .data = &decnet_dn_count,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &min_state_count,
+ .extra2 = &max_state_count
+ },
+ {
+ .procname = "di_count",
+ .data = &decnet_di_count,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &min_state_count,
+ .extra2 = &max_state_count
+ },
+ {
+ .procname = "dr_count",
+ .data = &decnet_dr_count,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &min_state_count,
+ .extra2 = &max_state_count
+ },
+ {
+ .procname = "dst_gc_interval",
+ .data = &decnet_dst_gc_interval,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &min_decnet_dst_gc_interval,
+ .extra2 = &max_decnet_dst_gc_interval
+ },
+ {
+ .procname = "no_fc_max_cwnd",
+ .data = &decnet_no_fc_max_cwnd,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &min_decnet_no_fc_max_cwnd,
+ .extra2 = &max_decnet_no_fc_max_cwnd
+ },
+ {
+ .procname = "decnet_mem",
+ .data = &sysctl_decnet_mem,
+ .maxlen = sizeof(sysctl_decnet_mem),
+ .mode = 0644,
+ .proc_handler = proc_doulongvec_minmax
+ },
+ {
+ .procname = "decnet_rmem",
+ .data = &sysctl_decnet_rmem,
+ .maxlen = sizeof(sysctl_decnet_rmem),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "decnet_wmem",
+ .data = &sysctl_decnet_wmem,
+ .maxlen = sizeof(sysctl_decnet_wmem),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "debug",
+ .data = &decnet_debug_level,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ { }
+};
+
+void dn_register_sysctl(void)
+{
+ dn_table_header = register_net_sysctl(&init_net, "net/decnet", dn_table);
+}
+
+void dn_unregister_sysctl(void)
+{
+ unregister_net_sysctl_table(dn_table_header);
+}
+
+#else /* CONFIG_SYSCTL */
+void dn_unregister_sysctl(void)
+{
+}
+void dn_register_sysctl(void)
+{
+}
+
+#endif