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Create helper functions for parsing boot args.

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boot_parse_arg		to parse a single arg
boot_parse_cmdline	to parse a command line string
boot_parse_args		to parse all the args in a vector
boot_howto_to_env	Convert howto bits to env vars
boot_env_to_howto	Return howto mask mased on what's set in the environment.

All these routines return an int that's the bitmask of the args
translated to RB_* flags. As a special case, the 'S' flag sets the
comconsole_speed env var. Any arg that looks like a=b will set the env
key 'a' to value 'b'. If =b is omitted, 'a' is set to '1'.  This
should help us reduce the number of redundant copies of these routines
in the tree.  It should also give a more uniform experience between
platforms.

Also, invent a new flag RB_PROBE that's set when 'P' is parsed.  On
x86 + BIOS, this means 'probe for the keyboard, and if it's not there
set both RB_MULTIPLE and RB_SERIAL (which means show the output on
both video and serial consoles, but make serial primary).  Others it
may be some similar concept of probing, but it's loader dependent
what, exactly, it means.

These routines are suitable for /boot/loader and/or the kernel,
though they may not be suitable for the tightly hand-rolled-for-space
environments like boot2.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D16205
This commit is contained in:
Warner Losh 2018-07-13 16:43:05 +00:00
parent dfe34cea0f
commit 52379d36a9
7 changed files with 251 additions and 60 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
stand/libsa/Makefile
View File

@ -37,6 +37,10 @@ SRCS+= bcmp.c bcopy.c bzero.c ffs.c fls.c \
.PATH: ${LIBC_SRC}/stdlib
SRCS+= abs.c strtol.c strtoll.c strtoul.c strtoull.c
# common boot code
.PATH: ${SYSDIR}/kern
SRCS+= subr_boot.c
.if ${MACHINE_CPUARCH} == "arm"
.PATH: ${LIBC_SRC}/arm/gen

36
sys/arm/arm/machdep_boot.c
View File

@ -68,6 +68,8 @@ __FBSDID("$FreeBSD$");
#define debugf(fmt, args...)
#endif
static char static_kenv[4096];
extern int *end;
static uint32_t board_revision;
@ -146,9 +148,8 @@ arm_print_kenv(void)
static void
cmdline_set_env(char *cmdline, const char *guard)
{
char *cmdline_next, *env;
char *cmdline_next;
size_t size, guard_len;
int i;
size = strlen(cmdline);
/* Skip leading spaces. */
@ -164,37 +165,27 @@ cmdline_set_env(char *cmdline, const char *guard)
size -= guard_len;
}
/* Skip leading spaces. */
for (; isspace(*cmdline) && (size > 0); cmdline++)
size--;
/* Replace ',' with '\0'. */
/* TODO: implement escaping for ',' character. */
cmdline_next = cmdline;
while(strsep(&cmdline_next, ",") != NULL)
;
init_static_kenv(cmdline, 0);
/* Parse boothowto. */
for (i = 0; howto_names[i].ev != NULL; i++) {
env = kern_getenv(howto_names[i].ev);
if (env != NULL) {
if (strtoul(env, NULL, 10) != 0)
boothowto |= howto_names[i].mask;
freeenv(env);
}
}
boothowto |= boot_parse_cmdline();
}
/*
* Called for armv6 and newer.
*/
void arm_parse_fdt_bootargs(void)
{
#ifdef FDT
if (loader_envp == NULL && fdt_get_chosen_bootargs(linux_command_line,
LBABI_MAX_COMMAND_LINE) == 0)
LBABI_MAX_COMMAND_LINE) == 0) {
init_static_kenv(static_kenv, sizeof(static_kenv));
cmdline_set_env(linux_command_line, CMDLINE_GUARD);
}
#endif
}
/*
* Called for armv[45].
*/
static vm_offset_t
linux_parse_boot_param(struct arm_boot_params *abp)
{
@ -271,6 +262,7 @@ linux_parse_boot_param(struct arm_boot_params *abp)
(char *)walker - (char *)atag_list + ATAG_SIZE(walker));
lastaddr = fake_preload_metadata(abp, NULL, 0);
init_static_kenv(static_kenv, sizeof(static_kenv));
cmdline_set_env(linux_command_line, CMDLINE_GUARD);
return lastaddr;
}

1
sys/conf/files
View File

@ -3868,6 +3868,7 @@ kern/subr_acl_nfs4.c optional ufs_acl | zfs
kern/subr_acl_posix1e.c optional ufs_acl
kern/subr_autoconf.c standard
kern/subr_blist.c standard
kern/subr_boot.c standard
kern/subr_bus.c standard
kern/subr_bus_dma.c standard
kern/subr_bufring.c standard

223
sys/kern/subr_boot.c Normal file
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@ -0,0 +1,223 @@
/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* All Rights Reserved.
* Copyright (c) 1998 Robert Nordier
* All Rights Reserved.
* Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@FreeBSD.org>
* All rights reserved.
* Copyright (c) 2014 Roger Pau Monné <roger.pau@citrix.com>
* All Rights Reserved.
* Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
* Copyright (c) 2018 Netflix
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/* Note: This is compiled in both the kernel and boot loader contexts */
#include <sys/param.h>
#ifdef _KERNEL
#include <sys/systm.h>
#else
#include <stand.h>
#endif
#include <sys/reboot.h>
#include <sys/boot.h>
#ifdef _KERNEL
#define SETENV(k, v) kern_setenv(k, v)
#define GETENV(k) kern_getenv(k)
#define FREE(v) freeenv(v)
#else /* Boot loader */
#define SETENV(k, v) setenv(k, v, 1)
#define GETENV(k) getenv(k)
#define FREE(v)
#endif
static struct
{
const char *ev;
int mask;
} howto_names[] = {
{ "boot_askname", RB_ASKNAME},
{ "boot_cdrom", RB_CDROM},
{ "boot_ddb", RB_KDB},
{ "boot_dfltroot", RB_DFLTROOT},
{ "boot_gdb", RB_GDB},
{ "boot_multicons", RB_MULTIPLE},
{ "boot_mute", RB_MUTE},
{ "boot_pause", RB_PAUSE},
{ "boot_serial", RB_SERIAL},
{ "boot_single", RB_SINGLE},
{ "boot_verbose", RB_VERBOSE},
{ NULL, 0}
};
/*
* In the boot environment, we often parse a command line and have to throw away
* its contents. As we do so, we set environment variables that correspond to
* the flags we encounter. Later, to get a howto mask, we grovel through these
* to reconstruct it. This also allows users in their loader.conf to set them
* and have the kernel see them.
*/
/**
* @brief convert the env vars in howto_names into a howto mask
*/
int
boot_env_to_howto(void)
{
int i, howto;
char *val;
for (howto = 0, i = 0; howto_names[i].ev != NULL; i++) {
val = GETENV(howto_names[i].ev);
if (val != NULL && strcasecmp(val, "no") != 0)
howto |= howto_names[i].mask;
FREE(val);
}
return (howto);
}
/**
* @brief Set env vars from howto_names based on howto passed in
*/
void
boot_howto_to_env(int howto)
{
int i;
for (i = 0; howto_names[i].ev != NULL; i++)
if (howto & howto_names[i].mask)
SETENV(howto_names[i].ev, "YES");
}
/**
* @brief Helper routine to parse a single arg and return its mask
*
* Parse all the - options to create a mask (or a serial speed in the
* case of -S). If the arg doesn't start with '-' assume it's an env
* variable and set that instead.
*/
int
boot_parse_arg(char *v)
{
char *n;
int howto;
#if 0
/* Need to see if this is better or worse than the meat of the #else */
static const char howto_switches[] = "aCdrgDmphsv";
static int howto_masks[] = {
RB_ASKNAME, RB_CDROM, RB_KDB, RB_DFLTROOT, RB_GDB, RB_MULTIPLE,
RB_MUTE, RB_PAUSE, RB_SERIAL, RB_SINGLE, RB_VERBOSE
};
opts = strchr(kargs, '-');
while (opts != NULL) {
while (*(++opts) != '\0') {
sw = strchr(howto_switches, *opts);
if (sw == NULL)
break;
howto |= howto_masks[sw - howto_switches];
}
opts = strchr(opts, '-');
}
#else
howto = 0;
if (*v == '-') {
while (*v != '\0') {
v++;
switch (*v) {
case 'a': howto |= RB_ASKNAME; break;
case 'C': howto |= RB_CDROM; break;
case 'd': howto |= RB_KDB; break;
case 'D': howto |= RB_MULTIPLE; break;
case 'm': howto |= RB_MUTE; break;
case 'g': howto |= RB_GDB; break;
case 'h': howto |= RB_SERIAL; break;
case 'p': howto |= RB_PAUSE; break;
case 'P': howto |= RB_PROBE; break;
case 'r': howto |= RB_DFLTROOT; break;
case 's': howto |= RB_SINGLE; break;
case 'S': SETENV("comconsole_speed", v + 1); v += strlen(v); break;
case 'v': howto |= RB_VERBOSE; break;
}
}
} else {
n = strsep(&v, "=");
if (v == NULL)
SETENV(n, "1");
else
SETENV(n, v);
}
#endif
return (howto);
}
/**
* @brief breakup the command line into args, and pass to boot_parse_arg
*/
int
boot_parse_cmdline_delim(char *cmdline, const char *delim)
{
char *v;
int howto;
howto = 0;
while ((v = strsep(&cmdline, delim)) != NULL) {
if (*v == '\0')
continue;
howto |= boot_parse_arg(v);
}
return (howto);
}
/**
* @brief Simplified interface for common 'space separated' args
*/
int
boot_parse_cmdline(char *cmdline)
{
return (boot_parse_cmdline_delim(cmdline, " \n"));
}
/**
* @brief Pass a vector of strings to boot_parse_arg
*/
int
boot_parse_args(int argc, char *argv[])
{
int i, howto;
howto = 0;
for (i = 1; i < argc; i++)
howto |= boot_parse_arg(argv[i]);
return (howto);
}

29
sys/sys/boot.h
View File

@ -1,6 +1,7 @@
/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2018 Netflix
* Copyright (c) 2014 Roger Pau Monné <roger.pau@citrix.com>
* All rights reserved.
*
@ -31,27 +32,11 @@
#ifndef _SYS_BOOT_H_
#define _SYS_BOOT_H_
/*
* Return a 'boothowto' value corresponding to the kernel arguments in
* (kargs) and any relevant environment variables.
*/
static struct
{
const char *ev;
int mask;
} howto_names[] = {
{ "boot_askname", RB_ASKNAME},
{ "boot_cdrom", RB_CDROM},
{ "boot_ddb", RB_KDB},
{ "boot_dfltroot", RB_DFLTROOT},
{ "boot_gdb", RB_GDB},
{ "boot_multicons", RB_MULTIPLE},
{ "boot_mute", RB_MUTE},
{ "boot_pause", RB_PAUSE},
{ "boot_serial", RB_SERIAL},
{ "boot_single", RB_SINGLE},
{ "boot_verbose", RB_VERBOSE},
{ NULL, 0}
};
int boot_env_to_howto(void);
void boot_howto_to_env(int howto);
int boot_parse_arg(char *v);
int boot_parse_cmdline_delim(char *cmdline, const char *delim);
int boot_parse_cmdline(char *cmdline);
int boot_parse_args(int argc, char *argv[]);
#endif /* !_SYS_BOOT_H_ */

1
sys/sys/reboot.h
View File

@ -63,6 +63,7 @@
#define RB_PAUSE 0x100000 /* pause after each output line during probe */
#define RB_REROOT 0x200000 /* unmount the rootfs and mount it again */
#define RB_POWERCYCLE 0x400000 /* Power cycle if possible */
#define RB_PROBE 0x10000000 /* Probe multiple consoles */
#define RB_MULTIPLE 0x20000000 /* use multiple consoles */
#define RB_BOOTINFO 0x80000000 /* have `struct bootinfo *' arg */

17
sys/x86/xen/pv.c
View File

@ -305,21 +305,6 @@ xen_pv_set_env(void)
init_static_kenv(cmd_line, 0);
}
static void
xen_pv_set_boothowto(void)
{
int i;
char *env;
/* get equivalents from the environment */
for (i = 0; howto_names[i].ev != NULL; i++) {
if ((env = kern_getenv(howto_names[i].ev)) != NULL) {
boothowto |= howto_names[i].mask;
freeenv(env);
}
}
}
#ifdef DDB
/*
* The way Xen loads the symtab is different from the native boot loader,
@ -418,7 +403,7 @@ xen_pv_parse_preload_data(u_int64_t modulep)
} else {
/* Parse the extra boot information given by Xen */
xen_pv_set_env();
xen_pv_set_boothowto();
boothowto |= boot_env_to_howto();
kmdp = NULL;
}