query_module()
requests information from the kernel about loadable modules.
The returned information is placed in the buffer pointed to by
buf.
The caller must specify the size of
buf
in
bufsize.
The precise nature and format of the returned information
depend on the operation specified by
which.
Some operations require
name
to identify a currently loaded module, some allow
name
to be NULL, indicating the kernel proper.
The following values can be specified for
which:
0
Returns success, if the kernel supports
query_module().
Used to probe for availability of the system call.
QM_MODULES
Returns the names of all loaded modules.
The returned buffer consists of a sequence of null-terminated strings;
ret
is set to the number of
modules.
QM_DEPS
Returns the names of all modules used by the indicated module.
The returned buffer consists of a sequence of null-terminated strings;
ret
is set to the number of modules.
QM_REFS
Returns the names of all modules using the indicated module.
This is the inverse of
QM_DEPS.
The returned buffer consists of a sequence of null-terminated strings;
ret
is set to the number of modules.
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
struct module_symbol {
unsigned long value;
unsigned long name;
};
followed by null-terminated strings.
The value of
name
is the character offset of the string relative to the start of
buf;
ret
is set to the number of symbols.
QM_INFO
Returns miscellaneous information about the indicated module.
The output buffer format is:
struct module_info {
unsigned long address;
unsigned long size;
unsigned long flags;
};
where
address
is the kernel address at which the module resides,
size
is the size of the module in bytes, and
flags
is a mask of
MOD_RUNNING,
MOD_AUTOCLEAN,
etc. that indicates the current status of the module
(see the kernel source file
include/linux/module.h).
ret
is set to the size of the
module_info
structure.
RETURN VALUE
On success, zero is returned.
On error, -1 is returned and
errno
is set appropriately.
ERRORS
EFAULT
At least one of
name,
buf,
or
ret
was outside the program's accessible address space.
EINVAL
Invalid
which;
or
name
is NULL (indicating "the kernel"),
but this is not permitted with the specified value of
which.
ENOENT
No module by that
name
exists.
ENOSPC
The buffer size provided was too small.
ret
is set to the minimum size needed.
ENOSYS
query_module()
is not supported in this version of the kernel.
CONFORMING TO
query_module()
is Linux-specific.
NOTES
This system call is only present on Linux up until kernel 2.4;
it was removed in Linux 2.6.
Some of the information that was available via
query_module()
can be obtained from
/proc/modules,
/proc/kallsyms,
and
/sys/modules.
This page is part of release 3.14 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
