kmem(7) kmem(7)
NAME [Toc] [Back]
kmem - perform I/O on kernel memory based on symbol name.
SYNOPSIS [Toc] [Back]
#include <sys/ksym.h>
int ioctl(int kmemfd, int command, void *rks);
DESCRIPTION [Toc] [Back]
When used with a valid file descriptor for /dev/kmem (kmemfd), ioctl
can be used to manipulate kernel memory. The specifics of this
manipulation depend on the command given as follows:
MIOC_READKSYM Read mirk_buflen bytes of kernel memory starting
at the address for mirk_symname into mirk_buf.
rks is a pointer to a mioc_rksym structure,
defined below.
MIOC_IREADKSYM Indirect read. Read sizeof(void *) bytes of
kernel memory starting at the address for
mirk_symname and use that as the address from
which to read mirk_buflen bytes of kernel memory
into mirk_buf. rks is a pointer to a mioc_rksym
structure.
MIOC_WRITEKSYM Write mirk_buflen bytes from mirk_buf into
kernel memory starting at the address for
mirk_symname. rks is a pointer to a mioc_rksym
structure.
MIOC_IWRITEKSYM Indirect write. Read sizeof(void *) bytes of
kernel memory starting at the address for
mirk_symname and use that as the kernel memory
address into which mirk_buflen bytes from
mirk_buf are written. rks is a pointer to a
mioc_rksym structure.
MIOC_LOCKSYM Increase the hold count by one for the
dynamically loaded module whose name is given by
rks, a pointer to a character string, thereby
preventing its unloading.
MIOC_UNLOCKSYM [Toc] [Back]
Decrease the hold count by one for the dynamically loaded module
whose name is given by rks, a pointer to a character string. If
the count is thereby reduced to 0, the module becomes a candidate
for unloading.
The struct mioc_rksym definition is:
struct mioc_rksym {
char * mirk_modname; /* limit search for symname
Hewlett-Packard Company - 1 - HP-UX 11i Version 2: August 2003
kmem(7) kmem(7)
to module modname; if NULL
use standard search order */
char * mirk_symname; /* name of symbol whose address
is the basis for this
operation */
void * mirk_buf; /* buffer into/from which
read/write takes place */
size_t mirk_buflen; /* length (in bytes) of desired
operation */
};
RETURN VALUE [Toc] [Back]
ioctl returns 0 upon successful completion. If an error occurs, a
value of -1 is returned and errno is set to indicate the error.
ERRORS [Toc] [Back]
In addition to the errors described in ioctl(2), the kmem ioctl also
fails if one or more of the following are true:
[EINVAL] modname does not represent a currently loaded
module or this is an MIOC_UNLOCKSYM and the hold
count is already 0.
[ENXIO] kmemfd open on wrong minor device (i.e., not
/dev/kmem).
[EBADF] kmemfd open for reading and this is an
MIOC_WRITEKSYM.
[ENOMATCH] symname not found.
[ENAMETOOLONG] modname is greater than MODMAXNAMELEN characters
long, or symname is greater that MAXSYMNMLEN
characters long.
SEE ALSO [Toc] [Back]
getksym(2), ioctl(2), ioctl(5).
Hewlett-Packard Company - 2 - HP-UX 11i Version 2: August 2003 [ Back ] |
