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diff --git a/usr/src/man/man5/loader.5 b/usr/src/man/man5/loader.5 new file mode 100644 index 0000000000..ef651b02a1 --- /dev/null +++ b/usr/src/man/man5/loader.5 @@ -0,0 +1,785 @@ +.\" Copyright (c) 1999 Daniel C. Sobral +.\" All rights reserved. +.\" +.\" 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. +.\" 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. +.\" +.Dd Apr 20, 2017 +.Dt LOADER 5 +.Os +.Sh NAME +.Nm loader +.Nd kernel bootstrapping final stage +.Sh DESCRIPTION +The +.Nm +is the final stage of +.Nm illumos Ns 's +kernel bootstrapping process. The actual name for the stage depends on +the platform. On IA32 (i386) architectures with BIOS firmware, it is a +.Pa BTX +client and named +.Nm zfsloader . +It is linked statically to libstand and usually located in the directory +.Pa /boot . +.Pp +.Nm +supports booting from +.Cm ZFS , +.Cm UFS , +.Cm PCFS , +.Cm HSFS +and +.Cm NFS +file systems. Additionally, +.Nm +can load files from the +.Cm TFTP +file service. The NFS and TFTP based boot is enabled via +.Xr pxeboot 5 . +The +.Nm +also does support uncompressing gzip files while reading. The uncompression +will happen automatically if the compressed file is stored without .gz +suffix or if the file is accessed by leaving out the .gz suffix from the name. +If the file is referred by full name, including .gz suffix, then the file +content is read as is and the uncompression is not performed. +.Pp +.Nm +provides a scripting language that can be used to +automate tasks, do pre-configuration or assist in recovery +procedures. +This scripting language is roughly divided in +two main components. +The smaller one is a set of commands +designed for direct use by the casual user, called "builtin +commands" for historical reasons. +The main drive behind these commands is user-friendliness. +The bigger component is an +.Tn ANS +Forth compatible Forth interpreter based on FICL, by +.An John Sadler . +.Pp +During initialization, +.Nm +will probe for a console and set the +.Va console +variable, or set it to serial console +.Pq Do Li ttya Dc - Dq Li ttyd +if the previous boot stage used that. +If multiple consoles are selected, they will be listed separated by commas. +Then, devices are probed, +.Va currdev +and +.Va loaddev +are set, and +.Va COLUMNS , +.Va LINES , +and +.Va ISADIR +are set. +Next, +.Tn FICL +is initialized, the builtin words are added to its vocabulary. +The inner interpreter +.Nm +will use with +.Tn FICL +is then set to +.Ic interpret , +which is +.Tn FICL Ns 's +default. +After that, +.Pa /boot/loader.rc +is processed if available. +These files are processed through the +.Ic include +command, which reads all of them into memory before processing them, +making disk changes possible. +.Pp +At this point, if an +.Ic autoboot +has not been tried, and if +.Va autoboot_delay +is not set to +.Dq Li NO +(not case sensitive), then an +.Ic autoboot +will be tried. +If the system gets past this point, +.Va prompt +will be set and +.Nm +will engage interactive mode. +Please note that historically even when +.Va autoboot_delay +is set to +.Dq Li 0 +user will be able to interrupt autoboot process by pressing some key +on the console while kernel and modules are being loaded. +In some +cases such behaviour may be undesirable, to prevent it set +.Va autoboot_delay +to +.Dq Li -1 , +in this case +.Nm +will engage interactive mode only if +.Ic autoboot +has failed. +.Ss Builtin Commands +In +.Nm , +builtin commands take parameters from the command line. +If an error condition occurs, an exception will be generated, +which can be intercepted using +.Tn ANS +Forth exception handling +words. +If not intercepted, an error message will be displayed and +the interpreter's state will be reset, emptying the stack and restoring +interpreting mode. +.Pp +The builtin commands available are: +.Pp +.Bl -tag -width Ds -compact +.It Ic autoboot Op Ar seconds Op Ar prompt +Proceeds to bootstrap the system after a number of seconds, if not +interrupted by the user. +Displays a countdown prompt +warning the user the system is about to be booted, +unless interrupted by a key press. +The kernel will be loaded first if necessary. +Defaults to 10 seconds. +.Pp +.It Ic bcachestat +Displays statistics about disk cache usage. +For debugging only. +.Pp +.It Ic boot +.It Ic boot Ar kernelname Op Cm ... +.It Ic boot Fl flag Cm ... +Immediately proceeds to bootstrap the system, loading the kernel +if necessary. +Any flags or arguments are passed to the kernel, but they +must precede the kernel name, if a kernel name is provided. +.Pp +.Em WARNING : +The behavior of this builtin is changed if +.Xr loader.4th 5 +is loaded. +.Pp +.It Ic chain Ar device +Chain load another boot loader from the specified device. Device can be either +disk name or partition. +.Pp +.It Ic echo Xo +.Op Fl n +.Op Aq message +.Xc +Displays text on the screen. +A new line will be printed unless +.Fl n +is specified. +.Pp +.It Ic heap +Displays memory usage statistics. +For debugging purposes only. +.Pp +.It Ic help Op topic Op subtopic +Shows help messages read from +.Pa /boot/loader.help . +The special topic +.Em index +will list the topics available. +.Pp +.It Ic include Ar file Op Ar +Process script files. +Each file, in turn, is completely read into memory, +and then each of its lines is passed to the command line interpreter. +If any error is returned by the interpreter, the include +command aborts immediately, without reading any other files, and +returns an error itself (see +.Sx ERRORS ) . +.Pp +.It Ic load Xo +.Op Fl t Ar type +.Ar file Cm ... +.Xc +Loads a kernel or file of opaque contents tagged as being of the type +.Ar type . +Kernel and modules can be either in a.out or ELF format. +Any arguments passed after the name of the file to be loaded +will be passed as arguments to that file. +.Pp +.It Ic ls Xo +.Op Fl l +.Op Ar path +.Xc +Displays a listing of files in the directory +.Ar path , +or the root directory if +.Ar path +is not specified. +If +.Fl l +is specified, file sizes will be shown too. +.Pp +.It Ic lsdev Op Fl v +Lists all of the devices from which it may be possible to load modules. +If +.Fl v +is specified, more details are printed. +.Pp +.It Ic lsmod Op Fl v +Displays loaded modules. +If +.Fl v +is specified, more details are shown. +.Pp +.It Ic more Ar file Op Ar +Display the files specified, with a pause at each +.Va LINES +displayed. +.Pp +.It Ic read Xo +.Op Fl t Ar seconds +.Op Fl p Ar prompt +.Op Va variable +.Xc +Reads a line of input from the terminal, storing it in +.Va variable +if specified. +A timeout can be specified with +.Fl t , +though it will be canceled at the first key pressed. +A prompt may also be displayed through the +.Fl p +flag. +.Pp +.It Ic reboot +Immediately reboots the system. +.Pp +.It Ic set Ar variable +.It Ic set Ar variable Ns = Ns Ar value +Set loader's environment variables. +.Pp +.It Ic show Op Va variable +Displays the specified variable's value, or all variables and their +values if +.Va variable +is not specified. +.Pp +.It Ic unload +Remove all modules from memory. +.Pp +.It Ic unset Va variable +Removes +.Va variable +from the environment. +.Pp +.It Ic \&? +Lists available commands. +.El +.Ss Builtin Environment Variables +The +.Nm +has actually two different kinds of +.Sq environment +variables. +There are ANS Forth's +.Em environmental queries , +and a separate space of environment variables used by builtins, which +are not directly available to Forth words. +It is the latter type that this section covers. +.Pp +Environment variables can be set and unset through the +.Ic set +and +.Ic unset +builtins, and can have their values interactively examined through the +use of the +.Ic show +builtin. +Their values can also be accessed as described in +.Sx BUILTIN PARSER . +.Pp +Notice that these environment variables are not inherited by any shell +after the system has been booted. +.Pp +A few variables are set automatically by +.Nm . +Others can affect the behavior of either +.Nm +or the kernel at boot. +Some options may require a value, +while others define behavior just by being set. +Both types of builtin variables are described below. +.Bl -tag -width bootfile +.It Va autoboot_delay +Number of seconds +.Ic autoboot +will wait before booting. +If this variable is not defined, +.Ic autoboot +will default to 10 seconds. +.Pp +If set to +.Dq Li NO , +no +.Ic autoboot +will be automatically attempted after processing +.Pa /boot/loader.rc , +though explicit +.Ic autoboot Ns 's +will be processed normally, defaulting to 10 seconds delay. +.Pp +If set to +.Dq Li 0 , +no delay will be inserted, but user still will be able to interrupt +.Ic autoboot +process and escape into the interactive mode by pressing some key +on the console while kernel and +modules are being loaded. +.Pp +If set to +.Dq Li -1 , +no delay will be inserted and +.Nm +will engage interactive mode only if +.Ic autoboot +has failed for some reason. +.It Va boot_ask +Will set +.Xr kernel 1M +.Fl a +option. +.It Va boot_debug +Will set +.Xr kernel 1M +.Fl d +option. +.It Va boot_kmdb +Will set +.Xr kernel 1M +.Fl k +option. +.It Va boot_reconfigure +Will set +.Xr kernel 1M +.Fl r +option. +.It Va boot_single +Will set +.Xr kernel 1M +.Fl s +option. +.It Va boot_verbose +Will set +.Xr kernel 1M +.Fl v +option. +.It Va boot-args +Will set custom arguments for the kernel. If set in +.Nm +configuration, the +.Nm +startup will parse the +.Va boot-args +value to set boot prefixed variables listed above, any unrecognized options +are added to kernel command line verbatim. +.It Va bootfile +The name of the kernel. +.It Va console +Defines the current console or consoles. +Multiple consoles may be specified. +In that case, the first listed console will become the default console for +the +.Xr kernel 1M . +.It Va currdev +Selects the default device. +Syntax for devices is odd. +.It Va interpret +Has the value +.Dq Li ok +if the Forth's current state is interpreting. +.It Va LINES +Define the number of lines on the screen, to be used by the pager. +.It Va module_path +Sets the list of directories which will be searched for modules +named in a load command or implicitly required by a dependency. +The default value for this variable is +.Dq Li /platform/i86pc/${ISADIR} +.It Va prompt +Value of +.Nm Ns 's +prompt. +Defaults to +.Dq Li "${interpret}" . +If variable +.Va prompt +is unset, the default prompt is +.Ql > . +.It Va os_console +If set, the value is used to set +.Xr kernel 1M +.Va console +property. +.El +.Pp +Other variables are used for loader or to set kernel properties or for +informational purposes. +.Ss Builtin Parser +When a builtin command is executed, the rest of the line is taken +by it as arguments, and it is processed by a special parser which +is not used for regular Forth commands. +.Pp +This special parser applies the following rules to the parsed text: +.Bl -enum +.It +All backslash characters are preprocessed. +.Bl -bullet +.It +\eb , \ef , \er , \en and \et are processed as in C. +.It +\es is converted to a space. +.It +\ev is converted to +.Tn ASCII +11. +.It +\ez is just skipped. +Useful for things like +.Dq \e0xf\ez\e0xf . +.It +\e0xN and \e0xNN are replaced by the hex N or NN. +.It +\eNNN is replaced by the octal NNN +.Tn ASCII +character. +.It +\e" , \e' and \e$ will escape these characters, preventing them from +receiving special treatment in Step 2, described below. +.It +\e\e will be replaced with a single \e . +.It +In any other occurrence, backslash will just be removed. +.El +.It +Every string between non-escaped quotes or double-quotes will be treated +as a single word for the purposes of the remaining steps. +.It +Replace any +.Li $VARIABLE +or +.Li ${VARIABLE} +with the value of the environment variable +.Va VARIABLE . +.It +Space-delimited arguments are passed to the called builtin command. +Spaces can also be escaped through the use of \e\e . +.El +.Pp +An exception to this parsing rule exists, and is described in +.Sx Builtins And FORTH . +.Ss Builtins And FORTH +All builtin words are state-smart, immediate words. +If interpreted, they behave exactly as described previously. +If they are compiled, though, +they extract their arguments from the stack instead of the command line. +.Pp +If compiled, the builtin words expect to find, at execution time, the +following parameters on the stack: +.D1 Ar addrN lenN ... addr2 len2 addr1 len1 N +where +.Ar addrX lenX +are strings which will compose the command line that will be parsed +into the builtin's arguments. +Internally, these strings are concatenated in from 1 to N, +with a space put between each one. +.Pp +If no arguments are passed, a 0 +.Em must +be passed, even if the builtin accepts no arguments. +.Pp +While this behavior has benefits, it has its trade-offs. +If the execution token of a builtin is acquired (through +.Ic ' +or +.Ic ['] ) , +and then passed to +.Ic catch +or +.Ic execute , +the builtin behavior will depend on the system state +.Bf Em +at the time +.Ic catch +or +.Ic execute +is processed! +.Ef +This is particularly annoying for programs that want or need to +handle exceptions. +In this case, the use of a proxy is recommended. +For example: +.Dl : (boot) boot ; +.Ss FICL +.Tn FICL +is a Forth interpreter written in C, in the form of a forth +virtual machine library that can be called by C functions and vice +versa. +.Pp +In +.Nm , +each line read interactively is then fed to +.Tn FICL , +which may call +.Nm +back to execute the builtin words. +The builtin +.Ic include +will also feed +.Tn FICL , +one line at a time. +.Pp +The words available to +.Tn FICL +can be classified into four groups. +The +.Tn ANS +Forth standard words, extra +.Tn FICL +words, extra +.Fx +words, and the builtin commands; +the latter were already described. +The +.Tn ANS +Forth standard words are listed in the +.Sx STANDARDS +section. +The words falling in the two other groups are described in the +following subsections. +.Ss FICL Extra Words +.Bl -tag -width wid-set-super +.It Ic .env +.It Ic .ver +.It Ic -roll +.It Ic 2constant +.It Ic >name +.It Ic body> +.It Ic compare +This is the STRING word set's +.Ic compare . +.It Ic compile-only +.It Ic endif +.It Ic forget-wid +.It Ic parse-word +.It Ic sliteral +This is the STRING word set's +.Ic sliteral . +.It Ic wid-set-super +.It Ic w@ +.It Ic w! +.It Ic x. +.It Ic empty +.It Ic cell- +.It Ic -rot +.El +.Ss Loader Extra Words +.Bl -tag -width XXXXXXXX +.It Ic \&$ Pq -- +Evaluates the remainder of the input buffer, after having printed it first. +.It Ic \&% Pq -- +Evaluates the remainder of the input buffer under a +.Ic catch +exception guard. +.It Ic .# +Works like +.Ic "." +but without outputting a trailing space. +.It Ic fclose Pq Ar fd -- +Closes a file. +.It Ic fkey Pq Ar fd -- char +Reads a single character from a file. +.It Ic fload Pq Ar fd -- +Processes a file +.Em fd . +.It Ic fopen Pq Ar addr len mode Li -- Ar fd +Opens a file. +Returns a file descriptor, or \-1 in case of failure. +The +.Ar mode +parameter selects whether the file is to be opened for read access, write +access, or both. +The constants +.Dv O_RDONLY , O_WRONLY , +and +.Dv O_RDWR +are defined in +.Pa /boot/forth/support.4th , +indicating read only, write only, and read-write access, respectively. +.It Xo +.Ic fread +.Pq Ar fd addr len -- len' +.Xc +Tries to read +.Em len +bytes from file +.Em fd +into buffer +.Em addr . +Returns the actual number of bytes read, or -1 in case of error or end of +file. +.It Ic heap? Pq -- Ar cells +Return the space remaining in the dictionary heap, in cells. +This is not related to the heap used by dynamic memory allocation words. +.It Ic inb Pq Ar port -- char +Reads a byte from a port. +.It Ic key Pq -- Ar char +Reads a single character from the console. +.It Ic key? Pq -- Ar flag +Returns +.Ic true +if there is a character available to be read from the console. +.It Ic ms Pq Ar u -- +Waits +.Em u +microseconds. +.It Ic outb Pq Ar port char -- +Writes a byte to a port. +.It Ic seconds Pq -- Ar u +Returns the number of seconds since midnight. +.It Ic tib> Pq -- Ar addr len +Returns the remainder of the input buffer as a string on the stack. +.El +.Ss Loader Defined Environmental Queries +.Bl -tag -width Ds +.It arch-i386 +.Ic TRUE +if the architecture is IA32. +.It loader_version +.Nm +version. +.El +.Ss Errors +The following values are thrown by +.Nm : +.Bl -tag -width XXXXX -offset indent +.It 100 +Any type of error in the processing of a builtin. +.It -1 +.Ic Abort +executed. +.It -2 +.Ic Abort" +executed. +.It -56 +.Ic Quit +executed. +.It -256 +Out of interpreting text. +.It -257 +Need more text to succeed -- will finish on next run. +.It -258 +.Ic Bye +executed. +.It -259 +Unspecified error. +.El +.Sh FILES +.Bl -tag -width /boot/defaults/loader.conf -compact +.It Pa /boot/defaults/loader.conf +.It Pa /boot/conf.d/* +.It Pa /boot/loader.conf +.It Pa /boot/loader.conf.local +.Nm +configuration files, as described in +.Xr loader.conf 5 . +.It Pa /boot/loader.help +Loaded by +.Ic help . +Contains the help messages. +.It Pa /boot/loader.rc +.Nm +bootstrapping script. +.It Pa /boot/forth/loader.4th +Extra builtin-like words. +.It Pa /boot/forth/support.4th +.Pa loader.conf +processing words. +.It Pa /boot/zfsloader +.Nm +itself. +.El +.Sh EXAMPLES +Boot in single user mode: +.Pp +.Dl boot -s +.Pp +Load the kernel, a boot_archive, and then autoboot in five seconds. +Notice that a kernel must be loaded before any other +.Ic load +command is attempted. +.Bd -literal -offset indent +load /platform/i86pc/kernel/amd64/unix +load -t rootfs /platform/i86pc/amd64/boot_archive +autoboot 5 +.Ed +.Sh SEE ALSO +.Xr boot 1M , +.Xr btxld 1onbld , +.Xr loader.conf 5 +.Sh STANDARDS +For the purposes of ANS Forth compliance, loader is an +.Bf Em +ANS Forth System with Environmental Restrictions, Providing +.Ef +.Bf Li +.No .( , +.No :noname , +.No ?do , +parse, pick, roll, refill, to, value, \e, false, true, +.No <> , +.No 0<> , +compile\&, , erase, nip, tuck +.Ef +.Em and +.Li marker +.Bf Em +from the Core Extensions word set, Providing the Exception Extensions +word set, Providing the Locals Extensions word set, Providing the +Memory-Allocation Extensions word set, Providing +.Ef +.Bf Li +\&.s, +bye, forget, see, words, +\&[if], +\&[else] +.Ef +.Em and +.Li [then] +.Bf Em +from the Programming-Tools extension word set, Providing the +Search-Order extensions word set. +.Ef |