diff options
Diffstat (limited to 'man2/query_module.2')
| -rw-r--r-- | man2/query_module.2 | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/man2/query_module.2 b/man2/query_module.2 new file mode 100644 index 0000000..519650a --- /dev/null +++ b/man2/query_module.2 @@ -0,0 +1,194 @@ +.\" Copyright (C) 1996 Free Software Foundation, Inc. +.\" +.\" SPDX-License-Identifier: GPL-1.0-or-later +.\" +.\" 2006-02-09, some reformatting by Luc Van Oostenryck; some +.\" reformatting and rewordings by mtk +.\" +.TH query_module 2 2023-03-30 "Linux man-pages 6.05.01" +.SH NAME +query_module \- query the kernel for various bits pertaining to modules +.SH SYNOPSIS +.nf +.B #include <linux/module.h> +.PP +.BI "[[deprecated]] int query_module(const char *" name ", int " which , +.BI " void " buf [. bufsize "], \ +size_t " bufsize , +.BI " size_t *" ret ); +.fi +.SH DESCRIPTION +.IR Note : +This system call is present only before Linux 2.6. +.PP +.BR query_module () +requests information from the kernel about loadable modules. +The returned information is placed in the buffer pointed to by +.IR buf . +The caller must specify the size of +.I buf +in +.IR bufsize . +The precise nature and format of the returned information +depend on the operation specified by +.IR which . +Some operations require +.I name +to identify a currently loaded module, some allow +.I name +to be NULL, indicating the kernel proper. +.PP +The following values can be specified for +.IR which : +.TP +.B 0 +Returns success, if the kernel supports +.BR query_module (). +Used to probe for availability of the system call. +.TP +.B QM_MODULES +Returns the names of all loaded modules. +The returned buffer consists of a sequence of null-terminated strings; +.I ret +is set to the number of +modules. +.\" ret is set on ENOSPC +.TP +.B QM_DEPS +Returns the names of all modules used by the indicated module. +The returned buffer consists of a sequence of null-terminated strings; +.I ret +is set to the number of modules. +.\" ret is set on ENOSPC +.TP +.B QM_REFS +Returns the names of all modules using the indicated module. +This is the inverse of +.BR QM_DEPS . +The returned buffer consists of a sequence of null-terminated strings; +.I ret +is set to the number of modules. +.\" ret is set on ENOSPC +.TP +.B QM_SYMBOLS +Returns the symbols and values exported by the kernel or the indicated +module. +The returned buffer is an array of structures of the following form +.\" ret is set on ENOSPC +.IP +.in +4n +.EX +struct module_symbol { + unsigned long value; + unsigned long name; +}; +.EE +.in +.IP +followed by null-terminated strings. +The value of +.I name +is the character offset of the string relative to the start of +.IR buf ; +.I ret +is set to the number of symbols. +.TP +.B QM_INFO +Returns miscellaneous information about the indicated module. +The output buffer format is: +.IP +.in +4n +.EX +struct module_info { + unsigned long address; + unsigned long size; + unsigned long flags; +}; +.EE +.in +.IP +where +.I address +is the kernel address at which the module resides, +.I size +is the size of the module in bytes, and +.I flags +is a mask of +.BR MOD_RUNNING , +.BR MOD_AUTOCLEAN , +and so on, that indicates the current status of the module +(see the Linux kernel source file +.IR include/linux/module.h ). +.I ret +is set to the size of the +.I module_info +structure. +.SH RETURN VALUE +On success, zero is returned. +On error, \-1 is returned and +.I errno +is set to indicate the error. +.SH ERRORS +.TP +.B EFAULT +At least one of +.IR name , +.IR buf , +or +.I ret +was outside the program's accessible address space. +.TP +.B EINVAL +Invalid +.IR which ; +or +.I name +is NULL (indicating "the kernel"), +but this is not permitted with the specified value of +.IR which . +.\" Not permitted with QM_DEPS, QM_REFS, or QM_INFO. +.TP +.B ENOENT +No module by that +.I name +exists. +.TP +.B ENOSPC +The buffer size provided was too small. +.I ret +is set to the minimum size needed. +.TP +.B ENOSYS +.BR query_module () +is not supported in this version of the kernel +(e.g., Linux 2.6 or later). +.SH STANDARDS +Linux. +.SH VERSIONS +Removed in Linux 2.6. +.\" Removed in Linux 2.5.48 +.PP +Some of the information that was formerly available via +.BR query_module () +can be obtained from +.IR /proc/modules , +.IR /proc/kallsyms , +and the files under the directory +.IR /sys/module . +.PP +The +.BR query_module () +system call is not supported by glibc. +No declaration is provided in glibc headers, but, +through a quirk of history, glibc does export an ABI for this system call. +Therefore, in order to employ this system call, +it is sufficient to manually declare the interface in your code; +alternatively, you can invoke the system call using +.BR syscall (2). +.SH SEE ALSO +.BR create_module (2), +.BR delete_module (2), +.BR get_kernel_syms (2), +.BR init_module (2), +.BR lsmod (8), +.BR modinfo (8) |