Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 544 insertions, 0 deletions

diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
new file mode 100644
index 000000000..056e93a81
--- /dev/null
+++ b/pc-bios/s390-ccw/netmain.c
@@ -0,0 +1,544 @@
+/*
+ * S390 virtio-ccw network boot loading program
+ *
+ * Copyright 2017 Thomas Huth, Red Hat Inc.
+ *
+ * Based on the S390 virtio-ccw loading program (main.c)
+ * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
+ *
+ * And based on the network loading code from SLOF (netload.c)
+ * Copyright (c) 2004, 2008 IBM Corporation
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <tftp.h>
+#include <ethernet.h>
+#include <dhcp.h>
+#include <dhcpv6.h>
+#include <ipv4.h>
+#include <ipv6.h>
+#include <dns.h>
+#include <time.h>
+#include <pxelinux.h>
+
+#include "s390-ccw.h"
+#include "cio.h"
+#include "virtio.h"
+#include "s390-time.h"
+
+#define DEFAULT_BOOT_RETRIES 10
+#define DEFAULT_TFTP_RETRIES 20
+
+extern char _start[];
+void write_iplb_location(void) {}
+
+#define KERNEL_ADDR             ((void *)0L)
+#define KERNEL_MAX_SIZE         ((long)_start)
+#define ARCH_COMMAND_LINE_SIZE  896              /* Taken from Linux kernel */
+
+/* STSI 3.2.2 offset of first vmdb + offset of uuid inside vmdb */
+#define STSI322_VMDB_UUID_OFFSET ((8 + 12) * 4)
+
+char stack[PAGE_SIZE * 8] __attribute__((aligned(PAGE_SIZE)));
+IplParameterBlock iplb __attribute__((aligned(PAGE_SIZE)));
+static char cfgbuf[2048];
+
+static SubChannelId net_schid = { .one = 1 };
+static uint8_t mac[6];
+static uint64_t dest_timer;
+
+void set_timer(int val)
+{
+    dest_timer = get_time_ms() + val;
+}
+
+int get_timer(void)
+{
+    return dest_timer - get_time_ms();
+}
+
+int get_sec_ticks(void)
+{
+    return 1000;    /* number of ticks in 1 second */
+}
+
+/**
+ * Obtain IP and configuration info from DHCP server (either IPv4 or IPv6).
+ * @param  fn_ip     contains the following configuration information:
+ *                   client MAC, client IP, TFTP-server MAC, TFTP-server IP,
+ *                   boot file name
+ * @param  retries   Number of DHCP attempts
+ * @return           0 : IP and configuration info obtained;
+ *                   non-0 : error condition occurred.
+ */
+static int dhcp(struct filename_ip *fn_ip, int retries)
+{
+    int i = retries + 1;
+    int rc = -1;
+
+    printf("  Requesting information via DHCP:     ");
+
+    dhcpv4_generate_transaction_id();
+    dhcpv6_generate_transaction_id();
+
+    do {
+        printf("\b\b\b%03d", i - 1);
+        if (!--i) {
+            printf("\nGiving up after %d DHCP requests\n", retries);
+            return -1;
+        }
+        fn_ip->ip_version = 4;
+        rc = dhcpv4(NULL, fn_ip);
+        if (rc == -1) {
+            fn_ip->ip_version = 6;
+            set_ipv6_address(fn_ip->fd, 0);
+            rc = dhcpv6(NULL, fn_ip);
+            if (rc == 0) {
+                memcpy(&fn_ip->own_ip6, get_ipv6_address(), 16);
+                break;
+            }
+        }
+        if (rc != -1) {    /* either success or non-dhcp failure */
+            break;
+        }
+    } while (1);
+    printf("\b\b\b\bdone\n");
+
+    return rc;
+}
+
+/**
+ * Seed the random number generator with our mac and current timestamp
+ */
+static void seed_rng(uint8_t mac[])
+{
+    uint64_t seed;
+
+    asm volatile(" stck %0 " : : "Q"(seed) : "memory");
+    seed ^= (mac[2] << 24) | (mac[3] << 16) | (mac[4] << 8) | mac[5];
+    srand(seed);
+}
+
+static int tftp_load(filename_ip_t *fnip, void *buffer, int len)
+{
+    tftp_err_t tftp_err;
+    int rc;
+
+    rc = tftp(fnip, buffer, len, DEFAULT_TFTP_RETRIES, &tftp_err);
+
+    if (rc < 0) {
+        /* Make sure that error messages are put into a new line */
+        printf("\n  ");
+    }
+
+    if (rc > 1024) {
+        printf("  TFTP: Received %s (%d KBytes)\n", fnip->filename, rc / 1024);
+    } else if (rc > 0) {
+        printf("  TFTP: Received %s (%d Bytes)\n", fnip->filename, rc);
+    } else {
+        const char *errstr = NULL;
+        int ecode;
+        tftp_get_error_info(fnip, &tftp_err, rc, &errstr, &ecode);
+        printf("TFTP error: %s\n", errstr ? errstr : "unknown error");
+    }
+
+    return rc;
+}
+
+static int net_init(filename_ip_t *fn_ip)
+{
+    int rc;
+
+    memset(fn_ip, 0, sizeof(filename_ip_t));
+
+    rc = virtio_net_init(mac);
+    if (rc < 0) {
+        puts("Could not initialize network device");
+        return -101;
+    }
+    fn_ip->fd = rc;
+
+    printf("  Using MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n",
+           mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+
+    set_mac_address(mac);    /* init ethernet layer */
+    seed_rng(mac);
+
+    rc = dhcp(fn_ip, DEFAULT_BOOT_RETRIES);
+    if (rc >= 0) {
+        if (fn_ip->ip_version == 4) {
+            set_ipv4_address(fn_ip->own_ip);
+        }
+    } else {
+        puts("Could not get IP address");
+        return -101;
+    }
+
+    if (fn_ip->ip_version == 4) {
+        printf("  Using IPv4 address: %d.%d.%d.%d\n",
+              (fn_ip->own_ip >> 24) & 0xFF, (fn_ip->own_ip >> 16) & 0xFF,
+              (fn_ip->own_ip >>  8) & 0xFF, fn_ip->own_ip & 0xFF);
+    } else if (fn_ip->ip_version == 6) {
+        char ip6_str[40];
+        ipv6_to_str(fn_ip->own_ip6.addr, ip6_str);
+        printf("  Using IPv6 address: %s\n", ip6_str);
+    }
+
+    if (rc == -2) {
+        printf("ARP request to TFTP server (%d.%d.%d.%d) failed\n",
+               (fn_ip->server_ip >> 24) & 0xFF, (fn_ip->server_ip >> 16) & 0xFF,
+               (fn_ip->server_ip >>  8) & 0xFF, fn_ip->server_ip & 0xFF);
+        return -102;
+    }
+    if (rc == -4 || rc == -3) {
+        puts("Can't obtain TFTP server IP address");
+        return -107;
+    }
+
+    printf("  Using TFTP server: ");
+    if (fn_ip->ip_version == 4) {
+        printf("%d.%d.%d.%d\n",
+               (fn_ip->server_ip >> 24) & 0xFF, (fn_ip->server_ip >> 16) & 0xFF,
+               (fn_ip->server_ip >>  8) & 0xFF, fn_ip->server_ip & 0xFF);
+    } else if (fn_ip->ip_version == 6) {
+        char ip6_str[40];
+        ipv6_to_str(fn_ip->server_ip6.addr, ip6_str);
+        printf("%s\n", ip6_str);
+    }
+
+    if (strlen(fn_ip->filename) > 0) {
+        printf("  Bootfile name: '%s'\n", fn_ip->filename);
+    }
+
+    return rc;
+}
+
+static void net_release(filename_ip_t *fn_ip)
+{
+    if (fn_ip->ip_version == 4) {
+        dhcp_send_release(fn_ip->fd);
+    }
+}
+
+/**
+ * Retrieve the Universally Unique Identifier of the VM.
+ * @return UUID string, or NULL in case of errors
+ */
+static const char *get_uuid(void)
+{
+    register int r0 asm("0");
+    register int r1 asm("1");
+    uint8_t *mem, *buf, uuid[16];
+    int i, cc, chk = 0;
+    static char uuid_str[37];
+
+    mem = malloc(2 * PAGE_SIZE);
+    if (!mem) {
+        puts("Out of memory ... can not get UUID.");
+        return NULL;
+    }
+    buf = (uint8_t *)(((uint64_t)mem + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1));
+    memset(buf, 0, PAGE_SIZE);
+
+    /* Get SYSIB 3.2.2 */
+    r0 = (3 << 28) | 2;
+    r1 = 2;
+    asm volatile(" stsi 0(%[addr])\n"
+                 " ipm  %[cc]\n"
+                 " srl  %[cc],28\n"
+                 : [cc] "=d" (cc)
+                 : "d" (r0), "d" (r1), [addr] "a" (buf)
+                 : "cc", "memory");
+    if (cc) {
+        free(mem);
+        return NULL;
+    }
+
+    for (i = 0; i < 16; i++) {
+        uuid[i] = buf[STSI322_VMDB_UUID_OFFSET + i];
+        chk |= uuid[i];
+    }
+    free(mem);
+    if (!chk) {
+        return NULL;
+    }
+
+    sprintf(uuid_str, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-"
+            "%02x%02x%02x%02x%02x%02x", uuid[0], uuid[1], uuid[2], uuid[3],
+            uuid[4], uuid[5], uuid[6], uuid[7], uuid[8], uuid[9], uuid[10],
+            uuid[11], uuid[12], uuid[13], uuid[14], uuid[15]);
+
+    return uuid_str;
+}
+
+/**
+ * Load a kernel with initrd (i.e. with the information that we've got from
+ * a pxelinux.cfg config file)
+ */
+static int load_kernel_with_initrd(filename_ip_t *fn_ip,
+                                   struct pl_cfg_entry *entry)
+{
+    int rc;
+
+    printf("Loading pxelinux.cfg entry '%s'\n", entry->label);
+
+    if (!entry->kernel) {
+        printf("Kernel entry is missing!\n");
+        return -1;
+    }
+
+    strncpy(fn_ip->filename, entry->kernel, sizeof(fn_ip->filename));
+    rc = tftp_load(fn_ip, KERNEL_ADDR, KERNEL_MAX_SIZE);
+    if (rc < 0) {
+        return rc;
+    }
+
+    if (entry->initrd) {
+        uint64_t iaddr = (rc + 0xfff) & ~0xfffUL;
+
+        strncpy(fn_ip->filename, entry->initrd, sizeof(fn_ip->filename));
+        rc = tftp_load(fn_ip, (void *)iaddr, KERNEL_MAX_SIZE - iaddr);
+        if (rc < 0) {
+            return rc;
+        }
+        /* Patch location and size: */
+        *(uint64_t *)0x10408 = iaddr;
+        *(uint64_t *)0x10410 = rc;
+        rc += iaddr;
+    }
+
+    if (entry->append) {
+        strncpy((char *)0x10480, entry->append, ARCH_COMMAND_LINE_SIZE);
+    }
+
+    return rc;
+}
+
+#define MAX_PXELINUX_ENTRIES 16
+
+static int net_try_pxelinux_cfg(filename_ip_t *fn_ip)
+{
+    struct pl_cfg_entry entries[MAX_PXELINUX_ENTRIES];
+    int num_ent, def_ent = 0;
+
+    num_ent = pxelinux_load_parse_cfg(fn_ip, mac, get_uuid(),
+                                      DEFAULT_TFTP_RETRIES,
+                                      cfgbuf, sizeof(cfgbuf),
+                                      entries, MAX_PXELINUX_ENTRIES, &def_ent);
+    if (num_ent > 0) {
+        return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
+    }
+
+    return -1;
+}
+
+/**
+ * Load via information from a .INS file (which can be found on CD-ROMs
+ * for example)
+ */
+static int handle_ins_cfg(filename_ip_t *fn_ip, char *cfg, int cfgsize)
+{
+    char *ptr;
+    int rc = -1, llen;
+    void *destaddr;
+    char *insbuf = cfg;
+
+    ptr = strchr(insbuf, '\n');
+    if (!ptr) {
+        puts("Does not seem to be a valid .INS file");
+        return -1;
+    }
+
+    *ptr = 0;
+    printf("\nParsing .INS file:\n %s\n", &insbuf[2]);
+
+    insbuf = ptr + 1;
+    while (*insbuf && insbuf < cfg + cfgsize) {
+        ptr = strchr(insbuf, '\n');
+        if (ptr) {
+            *ptr = 0;
+        }
+        llen = strlen(insbuf);
+        if (!llen) {
+            insbuf = ptr + 1;
+            continue;
+        }
+        ptr = strchr(insbuf, ' ');
+        if (!ptr) {
+            puts("Missing space separator in .INS file");
+            return -1;
+        }
+        *ptr = 0;
+        strncpy(fn_ip->filename, insbuf, sizeof(fn_ip->filename));
+        destaddr = (char *)atol(ptr + 1);
+        rc = tftp_load(fn_ip, destaddr, (long)_start - (long)destaddr);
+        if (rc <= 0) {
+            break;
+        }
+        insbuf += llen + 1;
+    }
+
+    return rc;
+}
+
+static int net_try_direct_tftp_load(filename_ip_t *fn_ip)
+{
+    int rc;
+    void *loadaddr = (void *)0x2000;  /* Load right after the low-core */
+
+    rc = tftp_load(fn_ip, loadaddr, KERNEL_MAX_SIZE - (long)loadaddr);
+    if (rc < 0) {
+        return rc;
+    } else if (rc < 8) {
+        printf("'%s' is too small (%i bytes only).\n", fn_ip->filename, rc);
+        return -1;
+    }
+
+    /* Check whether it is a configuration file instead of a kernel */
+    if (rc < sizeof(cfgbuf) - 1) {
+        memcpy(cfgbuf, loadaddr, rc);
+        cfgbuf[rc] = 0;    /* Make sure that it is NUL-terminated */
+        if (!strncmp("* ", cfgbuf, 2)) {
+            return handle_ins_cfg(fn_ip, cfgbuf, rc);
+        }
+        /*
+         * pxelinux.cfg support via bootfile name is just here for developers'
+         * convenience (it eases testing with the built-in DHCP server of QEMU
+         * that does not support RFC 5071). The official way to configure a
+         * pxelinux.cfg file name is to use DHCP options 209 and 210 instead.
+         * So only use the pxelinux.cfg parser here for files that start with
+         * a magic comment string.
+         */
+        if (!strncasecmp("# pxelinux", cfgbuf, 10)) {
+            struct pl_cfg_entry entries[MAX_PXELINUX_ENTRIES];
+            int num_ent, def_ent = 0;
+
+            num_ent = pxelinux_parse_cfg(cfgbuf, sizeof(cfgbuf), entries,
+                                         MAX_PXELINUX_ENTRIES, &def_ent);
+            if (num_ent <= 0) {
+                return -1;
+            }
+            return load_kernel_with_initrd(fn_ip, &entries[def_ent]);
+        }
+    }
+
+    /* Move kernel to right location */
+    memmove(KERNEL_ADDR, loadaddr, rc);
+
+    return rc;
+}
+
+void write_subsystem_identification(void)
+{
+    SubChannelId *schid = (SubChannelId *) 184;
+    uint32_t *zeroes = (uint32_t *) 188;
+
+    *schid = net_schid;
+    *zeroes = 0;
+}
+
+static bool find_net_dev(Schib *schib, int dev_no)
+{
+    int i, r;
+
+    for (i = 0; i < 0x10000; i++) {
+        net_schid.sch_no = i;
+        r = stsch_err(net_schid, schib);
+        if (r == 3 || r == -EIO) {
+            break;
+        }
+        if (!schib->pmcw.dnv) {
+            continue;
+        }
+        enable_subchannel(net_schid);
+        if (!virtio_is_supported(net_schid)) {
+            continue;
+        }
+        if (virtio_get_device_type() != VIRTIO_ID_NET) {
+            continue;
+        }
+        if (dev_no < 0 || schib->pmcw.dev == dev_no) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+static void virtio_setup(void)
+{
+    Schib schib;
+    int ssid;
+    bool found = false;
+    uint16_t dev_no;
+
+    /*
+     * We unconditionally enable mss support. In every sane configuration,
+     * this will succeed; and even if it doesn't, stsch_err() can deal
+     * with the consequences.
+     */
+    enable_mss_facility();
+
+    if (store_iplb(&iplb)) {
+        IPL_assert(iplb.pbt == S390_IPL_TYPE_CCW, "IPL_TYPE_CCW expected");
+        dev_no = iplb.ccw.devno;
+        debug_print_int("device no. ", dev_no);
+        net_schid.ssid = iplb.ccw.ssid & 0x3;
+        debug_print_int("ssid ", net_schid.ssid);
+        found = find_net_dev(&schib, dev_no);
+    } else {
+        for (ssid = 0; ssid < 0x3; ssid++) {
+            net_schid.ssid = ssid;
+            found = find_net_dev(&schib, -1);
+            if (found) {
+                break;
+            }
+        }
+    }
+
+    IPL_assert(found, "No virtio net device found");
+}
+
+void main(void)
+{
+    filename_ip_t fn_ip;
+    int rc, fnlen;
+
+    sclp_setup();
+    sclp_print("Network boot starting...\n");
+
+    virtio_setup();
+
+    rc = net_init(&fn_ip);
+    if (rc) {
+        panic("Network initialization failed. Halting.\n");
+    }
+
+    fnlen = strlen(fn_ip.filename);
+    if (fnlen > 0 && fn_ip.filename[fnlen - 1] != '/') {
+        rc = net_try_direct_tftp_load(&fn_ip);
+    }
+    if (rc <= 0) {
+        rc = net_try_pxelinux_cfg(&fn_ip);
+    }
+
+    net_release(&fn_ip);
+
+    if (rc > 0) {
+        sclp_print("Network loading done, starting kernel...\n");
+        jump_to_low_kernel();
+    }
+
+    panic("Failed to load OS from network\n");
+}