NetBSD-5.0.2/sys/kern/kern_lkm.c
/* $NetBSD: kern_lkm.c,v 1.98 2007/12/20 23:03:08 dsl Exp $ */
/*
* Copyright (c) 1994 Christopher G. Demetriou
* Copyright (c) 1992 Terrence R. Lambert.
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Terrence R. Lambert.
* 4. The name Terrence R. Lambert may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``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 TERRENCE R. LAMBERT 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.
*/
/*
* XXX it's not really safe to unload *any* of the types which are
* currently loadable; e.g. you could unload a syscall which was being
* blocked in, etc. In the long term, a solution should be come up
* with, but "not right now." -- cgd
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_lkm.c,v 1.98 2007/12/20 23:03:08 dsl Exp $");
#include "opt_ddb.h"
#include "opt_malloclog.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/file.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/exec.h>
#include <sys/syscallargs.h>
#include <sys/conf.h>
#include <sys/ksyms.h>
#include <sys/device.h>
#include <sys/once.h>
#include <sys/kauth.h>
#include <sys/lkm.h>
#include <sys/syscall.h>
#ifdef DDB
#include <machine/db_machdep.h>
#include <ddb/db_sym.h>
#endif
#include <uvm/uvm_extern.h>
struct vm_map *lkm_map;
#define LKM_SPACE_ALLOC(size, exec) \
uvm_km_alloc(lkm_map, (size), 0, \
UVM_KMF_WIRED | ((exec) ? UVM_KMF_EXEC : 0))
#define LKM_SPACE_FREE(addr, size) \
uvm_km_free(lkm_map, (addr), (size), UVM_KMF_WIRED)
#if !defined(DEBUG) && defined(LKMDEBUG)
# define DEBUG
#endif
#ifdef DEBUG
# define LKMDB_INFO 0x01
# define LKMDB_LOAD 0x02
int lkmdebug = 0;
#endif
#define LKM_ALLOC 0x01
#define LKMS_IDLE 0x00
#define LKMS_RESERVED 0x01
#define LKMS_LOADING 0x02
#define LKMS_UNLOADING 0x08
static int lkm_v = 0;
static int lkm_state = LKMS_IDLE;
static TAILQ_HEAD(lkms_head, lkm_table) lkmods = /* table of loaded modules */
TAILQ_HEAD_INITIALIZER(lkmods);
static struct lkm_table *curp; /* global for in-progress ops */
static struct lkm_table *lkmlookup(int, char *, int, int *);
static struct lkm_table *lkmalloc(void);
static void lkmfree(void);
static void lkmunreserve(int);
static int _lkm_syscall(struct lkm_table *, int);
static int _lkm_vfs(struct lkm_table *, int);
static int _lkm_dev(struct lkm_table *, int);
#ifdef STREAMS
static int _lkm_strmod(struct lkm_table *, int);
#endif
static int _lkm_exec(struct lkm_table *, int);
static int _lkm_compat(struct lkm_table *, int);
static int _lkm_drv(struct lkm_table *, int);
static int _lkm_checkver(struct lkm_table *);
dev_type_open(lkmopen);
dev_type_close(lkmclose);
dev_type_ioctl(lkmioctl);
const struct cdevsw lkm_cdevsw = {
lkmopen, lkmclose, noread, nowrite, lkmioctl,
nostop, notty, nopoll, nommap, nokqfilter, D_OTHER,
};
static ONCE_DECL(lkm_init_once);
static int
lkm_init(void)
{
/*
* If machine-dependent code hasn't initialized the lkm_map
* then just use kernel_map.
*/
if (lkm_map == NULL)
lkm_map = kernel_map;
return 0;
}
/*ARGSUSED*/
int
lkmopen(dev_t dev, int flag, int devtype, struct lwp *l)
{
int error;
RUN_ONCE(&lkm_init_once, lkm_init);
if (minor(dev) != 0)
return (ENXIO); /* bad minor # */
/*
* Use of the loadable kernel module device must be exclusive; we
* may try to remove this restriction later, but it's really no
* hardship.
*/
while (lkm_v & LKM_ALLOC) {
if (flag & FNONBLOCK) /* don't hang */
return (EBUSY);
/*
* Sleep pending unlock; we use tsleep() to allow
* an alarm out of the open.
*/
error = tsleep((void *)&lkm_v, TTIPRI|PCATCH, "lkmopn", 0);
if (error)
return (error);
}
lkm_v |= LKM_ALLOC;
return (0); /* pseudo-device open */
}
/*
* Look up for a LKM in the list.
*/
static struct lkm_table *
lkmlookup(int i, char *name, int need_copyin, int *error)
{
struct lkm_table *p;
char istr[MAXLKMNAME];
/*
* p being NULL here implies the list is empty, so any lookup is
* invalid (name based or otherwise). Since the list of modules is
* kept sorted by id, lowest to highest, the id of the last entry
* will be the highest in use.
*/
p = TAILQ_LAST(&lkmods, lkms_head);
if (p == NULL || i > p->id) {
*error = EINVAL;
return (NULL);
}
if (i < 0) { /* unload by name */
/*
* Copy name and lookup id from all loaded
* modules. May fail.
*/
if (need_copyin) {
*error = copyinstr(name, istr, MAXLKMNAME - 1, NULL);
if (*error)
return (NULL);
} else
strncpy(istr, name, MAXLKMNAME - 1);
istr[MAXLKMNAME - 1] = '\0';
TAILQ_FOREACH(p, &lkmods, link) {
if (strcmp(istr, p->private.lkm_any->lkm_name) == 0)
break;
}
} else
TAILQ_FOREACH(p, &lkmods, link)
if (i == p->id)
break;
if (p == NULL)
*error = ENOENT;
return (p);
}
/*
* Allocates memory for a new LKM table entry and inserts in the list.
* Returns NULL on failure.
*/
static struct lkm_table *
lkmalloc(void)
{
struct lkm_table *p, *ret;
int id = 0;
ret = malloc(sizeof(struct lkm_table), M_DEVBUF, M_NOWAIT);
if (ret == NULL)
return (NULL);
ret->refcnt = 0;
ret->forced = 0;
/* find the first unused id */
TAILQ_FOREACH(p, &lkmods, link) {
if (id != p->id)
break;
id++;
}
ret->id = id;
if (p == NULL)
TAILQ_INSERT_TAIL(&lkmods, ret, link);
else
TAILQ_INSERT_BEFORE(p, ret, link);
return (ret);
}
/*
* Frees the current LKM table entry.
*/
static void
lkmfree(void)
{
TAILQ_REMOVE(&lkmods, curp, link);
free(curp, M_DEVBUF);
curp = NULL;
}
/*
* Unreserve the memory associated with the current loaded module; done on
* a coerced close of the lkm device (close on premature exit of modload)
* or explicitly by modload as a result of a link failure.
*/
static void
lkmunreserve(int delsymtab)
{
if (lkm_state == LKMS_IDLE)
return;
if (curp && curp->syms) {
if (delsymtab)
ksyms_delsymtab(curp->private.lkm_any->lkm_name);
LKM_SPACE_FREE(curp->syms, curp->sym_size);
curp->syms = 0;
}
/*
* Actually unreserve the memory
*/
if (curp && curp->area) {
LKM_SPACE_FREE(curp->area, curp->size);
curp->area = 0;
}
if (curp && curp->forced)
curp->forced = 0;
lkm_state = LKMS_IDLE;
}
int
lkmclose(dev_t dev, int flag, int mode, struct lwp *l)
{
if (!(lkm_v & LKM_ALLOC)) {
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO)
printf("LKM: close before open!\n");
#endif /* DEBUG */
return (EBADF);
}
/* do this before waking the herd... */
if (curp != NULL && curp->refcnt == 0) {
/*
* If we close before setting used, we have aborted
* by way of error or by way of close-on-exit from
* a premature exit of "modload".
*/
lkmunreserve(1); /* coerce state to LKM_IDLE */
lkmfree();
}
lkm_v &= ~LKM_ALLOC;
wakeup((void *)&lkm_v); /* thundering herd "problem" here */
return (0); /* pseudo-device closed */
}
/*ARGSUSED*/
int
lkmioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
{
int i, error = 0;
struct lmc_resrv *resrvp;
struct lmc_loadbuf *loadbufp;
struct lmc_unload *unloadp;
struct lmc_stat *statp;
switch(cmd) {
case LMRESERV: /* reserve pages for a module */
if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_LKM,
0, (void *)cmd, NULL, NULL))
return EPERM;
if ((flag & FWRITE) == 0) /* only allow this if writing */
return EPERM;
resrvp = (struct lmc_resrv *)data;
curp = lkmalloc();
if (curp == NULL) {
error = ENOMEM;
break;
}
resrvp->slot = curp->id; /* return slot */
/*
* Get memory for module
*/
curp->size = resrvp->size;
curp->area = LKM_SPACE_ALLOC(curp->size, 1);
curp->offset = 0; /* load offset */
resrvp->addr = curp->area; /* ret kernel addr */
if (resrvp->sym_size) {
curp->sym_size = resrvp->sym_size;
curp->sym_symsize = resrvp->sym_symsize;
curp->syms = (u_long)LKM_SPACE_ALLOC(curp->sym_size, 0);
curp->sym_offset = 0;
resrvp->sym_addr = curp->syms; /* ret symbol addr */
} else {
curp->sym_size = 0;
curp->syms = 0;
curp->sym_offset = 0;
resrvp->sym_addr = 0;
}
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO) {
printf("LKM: LMRESERV (actual = 0x%08lx)\n",
curp->area);
printf("LKM: LMRESERV (syms = 0x%08lx)\n",
curp->syms);
printf("LKM: LMRESERV (adjusted = 0x%08lx)\n",
trunc_page(curp->area));
}
#endif /* DEBUG */
lkm_state = LKMS_RESERVED;
break;
case LMLOADBUF: /* Copy in; stateful, follows LMRESERV */
if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_LKM,
0, (void *)cmd, NULL, NULL))
return EPERM;
if ((flag & FWRITE) == 0) /* only allow this if writing */
return EPERM;
loadbufp = (struct lmc_loadbuf *)data;
i = loadbufp->cnt;
if ((lkm_state != LKMS_RESERVED && lkm_state != LKMS_LOADING)
|| i < 0
|| i > MODIOBUF
|| i > curp->size - curp->offset) {
error = ENOMEM;
break;
}
/* copy in buffer full of data */
error = copyin(loadbufp->data,
(char *)curp->area + curp->offset, i);
if (error)
break;
#ifdef PMAP_NEED_PROCWR
pmap_procwr(&proc0, curp->area + curp->offset, i);
#endif
if ((curp->offset + i) < curp->size) {
lkm_state = LKMS_LOADING;
#ifdef DEBUG
if (lkmdebug & LKMDB_LOAD)
printf("LKM: LMLOADBUF (loading @ %ld of %ld, i = %d)\n",
curp->offset, curp->size, i);
#endif /* DEBUG */
}
curp->offset += i;
break;
case LMLOADSYMS: /* Copy in; stateful, follows LMRESERV*/
if ((flag & FWRITE) == 0) /* only allow this if writing */
return EPERM;
loadbufp = (struct lmc_loadbuf *)data;
i = loadbufp->cnt;
if ((lkm_state != LKMS_LOADING)
|| i < 0
|| i > MODIOBUF
|| i > curp->sym_size - curp->sym_offset) {
error = ENOMEM;
break;
}
/* copy in buffer full of data*/
if ((error = copyin(loadbufp->data,
(char *)(curp->syms) + curp->sym_offset,
i)) != 0)
break;
if ((curp->sym_offset + i) < curp->sym_size) {
lkm_state = LKMS_LOADING;
#ifdef DEBUG
if (lkmdebug & LKMDB_LOAD)
printf( "LKM: LMLOADSYMS (loading @ %ld of %ld, i = %d)\n",
curp->sym_offset, curp->sym_size, i);
#endif /* DEBUG*/
}
curp->sym_offset += i;
break;
case LMUNRESRV: /* discard reserved pages for a module */
if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_LKM,
0, (void *)cmd, NULL, NULL))
return EPERM;
if ((flag & FWRITE) == 0) /* only allow this if writing */
return EPERM;
lkmunreserve(0); /* coerce state to LKM_IDLE */
if (curp != NULL)
lkmfree();
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO)
printf("LKM: LMUNRESERV\n");
#endif /* DEBUG */
break;
case LMREADY: /* module loaded: call entry */
if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_LKM,
0, (void *)cmd, NULL, NULL))
return EPERM;
if ((flag & FWRITE) == 0) /* only allow this if writing */
return EPERM;
if (lkm_state != LKMS_LOADING) {
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO)
printf("lkm_state is %02x\n", lkm_state);
#endif /* DEBUG */
return ENXIO;
}
if (curp->size - curp->offset > 0) {
/* The remainder must be bss, so we clear it */
memset((char *)curp->area + curp->offset, 0,
curp->size - curp->offset);
}
#ifdef DDB
/*
* Temporarily load the symbol table before the entry
* routine is called, so that the symbols are available
* for DDB backtrace and breakpoints.
*/
if (curp->syms && curp->sym_offset >= curp->sym_size) {
error = ksyms_addsymtab("/lkmtemp/",
(char *)curp->syms, curp->sym_symsize,
(char *)curp->syms + curp->sym_symsize,
curp->sym_size - curp->sym_symsize);
if (error)
goto rdyfail;
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO)
printf( "DDB symbols added!\n" );
#endif
}
#endif /* DDB */
curp->entry = (int (*)(struct lkm_table *, int, int))
(*((long *) (data)));
/* call entry(load)... (assigns "private" portion) */
error = (*(curp->entry))(curp, LKM_E_LOAD, LKM_VERSION);
if (curp->syms && curp->sym_offset >= curp->sym_size) {
#ifdef DDB
ksyms_delsymtab("/lkmtemp/");
#endif
if (!error) {
error = ksyms_addsymtab(curp->private.lkm_any->lkm_name,
(char *)curp->syms, curp->sym_symsize,
(char *)curp->syms + curp->sym_symsize,
curp->sym_size - curp->sym_symsize);
}
}
if (error) {
#ifdef DDB
rdyfail:
#endif
/*
* Module may refuse loading or may have a
* version mismatch...
*/
lkm_state = LKMS_UNLOADING; /* for lkmunreserve */
lkmunreserve(0); /* free memory */
lkmfree(); /* free slot */
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO)
printf("lkm entry point failed with error %d\n",
error);
#endif /* DEBUG */
break;
}
curp->refcnt++;
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO)
printf("LKM: LMREADY\n");
#endif /* DEBUG */
lkm_state = LKMS_IDLE;
break;
case LMUNLOAD: /* unload a module */
if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_LKM,
0, (void *)cmd, NULL, NULL))
return EPERM;
if ((flag & FWRITE) == 0) /* only allow this if writing */
return EPERM;
unloadp = (struct lmc_unload *)data;
curp = lkmlookup(unloadp->id, unloadp->name, 1, &error);
if (curp == NULL)
break;
/* call entry(unload) */
if ((*(curp->entry))(curp, LKM_E_UNLOAD, LKM_VERSION)) {
error = EBUSY;
break;
}
lkm_state = LKMS_UNLOADING; /* non-idle for lkmunreserve */
lkmunreserve(1); /* free memory */
lkmfree(); /* free slot */
break;
case LMSTAT: /* stat a module by id/name */
/* allow readers and writers to stat */
statp = (struct lmc_stat *)data;
if ((curp = lkmlookup(statp->id, statp->name, 0, &error)) == NULL)
break;
if ((error = (*curp->entry)(curp, LKM_E_STAT, LKM_VERSION)))
break;
/*
* Copy out stat information for this module...
*/
statp->id = curp->id;
statp->offset = curp->private.lkm_any->lkm_offset;
statp->type = curp->private.lkm_any->lkm_type;
statp->area = curp->area;
statp->size = curp->size / 1024;
statp->private = (unsigned long)curp->private.lkm_any;
statp->ver = LKM_VERSION;
copystr(curp->private.lkm_any->lkm_name,
statp->name,
MAXLKMNAME - 2,
(size_t *)0);
break;
#ifdef LMFORCE
case LMFORCE: /* stateful, optionally follows LMRESERV */
if (kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_LKM,
0, (void *)cmd, NULL, NULL))
return EPERM;
if ((flag & FWRITE) == 0) /* only allow this if writing */
return EPERM;
if (lkm_state != LKMS_RESERVED) {
error = EPERM;
break;
}
curp->forced = (*(u_long *)data != 0);
break;
#endif /* LMFORCE */
default: /* bad ioctl()... */
error = ENOTTY;
break;
}
return (error);
}
/*
* Acts like "nosys" but can be identified in sysent for dynamic call
* number assignment for a limited number of calls.
*
* Place holder for system call slots reserved for loadable modules.
*/
int
sys_lkmnosys(struct lwp *l, const void *v, register_t *retval)
{
return (sys_nosys(l, v, retval));
}
/*
* A placeholder function for load/unload/stat calls; simply returns zero.
* Used where people don't want to specify a special function.
*/
int
lkm_nofunc(struct lkm_table *lkmtp, int cmd)
{
return (0);
}
int
lkmexists(struct lkm_table *lkmtp)
{
struct lkm_table *p;
/* see if name exists... */
TAILQ_FOREACH(p, &lkmods, link) {
if (strcmp(lkmtp->private.lkm_any->lkm_name,
p->private.lkm_any->lkm_name) == 0 && (p->refcnt != 0))
return (1); /* already loaded... */
}
return (0); /* module not loaded... */
}
/*
* For the loadable system call described by the structure pointed to
* by lkmtp, load/unload/stat it depending on the cmd requested.
*/
static int
_lkm_syscall(struct lkm_table *lkmtp, int cmd)
{
struct lkm_syscall *args = lkmtp->private.lkm_syscall;
int i;
int error = 0;
switch(cmd) {
case LKM_E_LOAD:
/* don't load twice! */
if (lkmexists(lkmtp))
return (EEXIST);
if ((i = args->mod.lkm_offset) == -1) { /* auto */
/*
* Search the table looking for a slot...
*/
for (i = 0; i < SYS_MAXSYSCALL; i++)
if (sysent[i].sy_call == sys_lkmnosys)
break; /* found it! */
/* out of allocable slots? */
if (i == SYS_MAXSYSCALL) {
error = ENFILE;
break;
}
} else { /* assign */
if (i < 0 || i >= SYS_MAXSYSCALL) {
error = EINVAL;
break;
}
}
/* save old */
memcpy(&args->lkm_oldent, &sysent[i], sizeof(struct sysent));
/* replace with new */
memcpy(&sysent[i], args->lkm_sysent, sizeof(struct sysent));
/* done! */
args->mod.lkm_offset = i; /* slot in sysent[] */
break;
case LKM_E_UNLOAD:
/* current slot... */
i = args->mod.lkm_offset;
/* replace current slot contents with old contents */
memcpy(&sysent[i], &args->lkm_oldent, sizeof(struct sysent));
break;
case LKM_E_STAT: /* no special handling... */
break;
}
return (error);
}
/*
* For the loadable virtual file system described by the structure pointed
* to by lkmtp, load/unload/stat it depending on the cmd requested.
*/
static int
_lkm_vfs(struct lkm_table *lkmtp, int cmd)
{
struct lkm_vfs *args = lkmtp->private.lkm_vfs;
int error = 0;
switch(cmd) {
case LKM_E_LOAD:
/* don't load twice! */
if (lkmexists(lkmtp))
return (EEXIST);
/* Establish the file system. */
if ((error = vfs_attach(args->lkm_vfsops)) != 0)
return (error);
/* done! */
break;
case LKM_E_UNLOAD:
/* Disestablish the file system. */
if ((error = vfs_detach(args->lkm_vfsops)) != 0)
return (error);
break;
case LKM_E_STAT: /* no special handling... */
break;
}
return (error);
}
/*
* For the loadable device driver described by the structure pointed to
* by lkmtp, load/unload/stat it depending on the cmd requested.
*/
static int
_lkm_dev(struct lkm_table *lkmtp, int cmd)
{
struct lkm_dev *args = lkmtp->private.lkm_dev;
int error;
switch(cmd) {
case LKM_E_LOAD:
/* don't load twice! */
if (lkmexists(lkmtp))
return (EEXIST);
error = devsw_attach(args->lkm_devname,
args->lkm_bdev, &args->lkm_bdevmaj,
args->lkm_cdev, &args->lkm_cdevmaj);
if (error != 0)
return (error);
args->mod.lkm_offset =
LKM_MAKEMAJOR(args->lkm_bdevmaj, args->lkm_cdevmaj);
break;
case LKM_E_UNLOAD:
devsw_detach(args->lkm_bdev, args->lkm_cdev);
args->lkm_bdevmaj = -1;
args->lkm_cdevmaj = -1;
break;
case LKM_E_STAT: /* no special handling... */
break;
}
return (0);
}
#ifdef STREAMS
/*
* For the loadable streams module described by the structure pointed to
* by lkmtp, load/unload/stat it depending on the cmd requested.
*/
static int
_lkm_strmod(struct lkm_table *lkmtp, int cmd)
{
struct lkm_strmod *args = lkmtp->private.lkm_strmod;
int i;
int error = 0;
switch(cmd) {
case LKM_E_LOAD:
/* don't load twice! */
if (lkmexists(lkmtp))
return (EEXIST);
break;
case LKM_E_UNLOAD:
break;
case LKM_E_STAT: /* no special handling... */
break;
}
return (error);
}
#endif /* STREAMS */
/*
* For the loadable execution class described by the structure pointed to
* by lkmtp, load/unload/stat it depending on the cmd requested.
*/
static int
_lkm_exec(struct lkm_table *lkmtp, int cmd)
{
struct lkm_exec *args = lkmtp->private.lkm_exec;
int error = 0;
switch(cmd) {
case LKM_E_LOAD:
/* don't load twice! */
if (lkmexists(lkmtp))
return (EEXIST);
/* this would also fill in the emulation pointer in
* args->lkm_execsw */
error = exec_add(args->lkm_execsw, args->lkm_emul);
break;
case LKM_E_UNLOAD:
error = exec_remove(args->lkm_execsw);
break;
case LKM_E_STAT: /* no special handling... */
break;
}
return (error);
}
/*
* For the loadable compat/emulation class described by the structure pointed to
* by lkmtp, load/unload/stat it depending on the cmd requested.
*/
static int
_lkm_compat(struct lkm_table *lkmtp, int cmd)
{
struct lkm_compat *args = lkmtp->private.lkm_compat;
int error = 0;
switch(cmd) {
case LKM_E_LOAD:
/* don't load twice! */
if (lkmexists(lkmtp))
return (EEXIST);
error = emul_register(args->lkm_compat, 0);
break;
case LKM_E_UNLOAD:
error = emul_unregister(args->lkm_compat->e_name);
break;
case LKM_E_STAT: /* no special handling... */
break;
}
return (error);
}
static int
drvlkm_load(struct cfdriver **cd, const struct cfattachlkminit *cai,
struct cfdata *cf)
{
const struct cfattachlkminit *cfai;
int i, error, j;
for (i = 0; cd[i]; i++) {
error = config_cfdriver_attach(cd[i]);
if (!error)
continue;
if (error != EEXIST) {
printf("%s: unable to register driver\n",
cd[i]->cd_name);
/* XXX roll back previous attachments */
goto out;
}
printf("driver %s already present\n", cd[i]->cd_name);
/*
* get existing drivers out of the list so we won't try
* to detach them
*/
for (j = i; cd[j]; j++)
cd[j] = cd[j + 1];
i--; /* continue at same index */
}
for (cfai = cai; cfai->cfai_name; cfai++) {
for (i = 0; cfai->cfai_list[i]; i++) {
error = config_cfattach_attach(cfai->cfai_name,
cfai->cfai_list[i]);
if (!error)
continue;
if (error != EEXIST) {
printf("%s: unable to register cfattach\n",
cfai->cfai_list[i]->ca_name);
/* XXX roll back previous attachments */
goto out;
}
printf("driver attachment %s for %s already present\n",
cfai->cfai_list[i]->ca_name, cfai->cfai_name);
/*
* get existing attachments out of the list so we
* won't try to detach them
*/
for (j = i; cfai->cfai_list[j]; j++)
cfai->cfai_list[j] = cfai->cfai_list[j + 1];
i--; /* continue at same index */
}
}
error = config_cfdata_attach(cf, 1);
/* XXX roll back cfdriver / cfattach attachments in error case */
out:
return (error);
}
static int
drvlkm_unload(struct cfdriver **cd, const struct cfattachlkminit *cai,
struct cfdata *cf)
{
const struct cfattachlkminit *cfai;
int i, error;
error = config_cfdata_detach(cf);
if (error)
return (error);
for (cfai = cai; cfai->cfai_name; cfai++) {
for (i = 0; cfai->cfai_list[i]; i++) {
error = config_cfattach_detach(cfai->cfai_name,
cfai->cfai_list[i]);
if (error) {
printf("%s: unable to deregister cfattach\n",
cfai->cfai_list[i]->ca_name);
return (error);
}
}
}
for (i = 0; cd[i]; i++) {
error = config_cfdriver_detach(cd[i]);
if (error) {
printf("%s: unable to deregister cfdriver\n",
cd[i]->cd_name);
return (error);
}
}
return (0);
}
static int
_lkm_drv(struct lkm_table *lkmtp, int cmd)
{
struct lkm_drv *args = lkmtp->private.lkm_drv;
int error = 0;
switch(cmd) {
case LKM_E_LOAD:
/* don't load twice! */
if (lkmexists(lkmtp))
return (EEXIST);
error = drvlkm_load(args->lkm_cd,
args->lkm_cai,
args->lkm_cf);
break;
case LKM_E_UNLOAD:
error = drvlkm_unload(args->lkm_cd,
args->lkm_cai,
args->lkm_cf);
break;
case LKM_E_STAT: /* no special handling... */
break;
}
return (error);
}
/*
* This code handles the per-module type "wiring-in" of loadable modules
* into existing kernel tables. For "LM_MISC" modules, wiring and unwiring
* is assumed to be done in their entry routines internal to the module
* itself.
*/
int
lkmdispatch(struct lkm_table *lkmtp, int cmd)
{
int error = 0; /* default = success */
#ifdef DEBUG
if (lkmdebug & LKMDB_INFO)
printf( "lkmdispatch: %p %d\n", lkmtp, cmd );
#endif
/* If loading, check the LKM is compatible */
if (cmd == LKM_E_LOAD) {
if (_lkm_checkver(lkmtp))
return (EPROGMISMATCH);
}
switch(lkmtp->private.lkm_any->lkm_type) {
case LM_SYSCALL:
error = _lkm_syscall(lkmtp, cmd);
break;
case LM_VFS:
error = _lkm_vfs(lkmtp, cmd);
break;
case LM_DEV:
error = _lkm_dev(lkmtp, cmd);
break;
#ifdef STREAMS
case LM_STRMOD:
{
struct lkm_strmod *args = lkmtp->private.lkm_strmod;
}
break;
#endif /* STREAMS */
case LM_EXEC:
error = _lkm_exec(lkmtp, cmd);
break;
case LM_COMPAT:
error = _lkm_compat(lkmtp, cmd);
break;
case LM_MISC: /* ignore content -- no "misc-specific" procedure */
break;
case LM_DRV:
error = _lkm_drv(lkmtp, cmd);
break;
default:
error = ENXIO; /* unknown type */
break;
}
return (error);
}
/*
* Check LKM version against current kernel.
*/
static int
_lkm_checkver(struct lkm_table *lkmtp)
{
struct lkm_any *mod = lkmtp->private.lkm_any;
if (mod->lkm_modver != LKM_VERSION) {
printf("LKM '%s': LKM version mismatch - LKM %d, kernel %d\n",
mod->lkm_name, mod->lkm_modver, LKM_VERSION);
return (1);
}
if (lkmtp->forced) {
printf("LKM '%s': forced load, skipping compatibility checks\n",
mod->lkm_name);
return (0);
}
if (mod->lkm_sysver != __NetBSD_Version__) {
printf("LKM '%s': kernel version mismatch - LKM %d, kernel %d\n",
mod->lkm_name, mod->lkm_sysver, __NetBSD_Version__);
return (2);
}
/*
* Following might eventually be changed to take into account envdep,
* if it's non-NULL.
*/
if (strcmp(mod->lkm_envver, _LKM_ENV_VERSION) != 0) {
const char *kenv = _LKM_ENV_VERSION;
const char *envver = mod->lkm_envver;
if (kenv[0] == ',')
kenv++;
if (envver[0] == ',')
envver++;
printf("LKM '%s': environment compile options mismatch - LKM '%s', kernel '%s'\n",
mod->lkm_name, envver, kenv);
return (3);
}
/*
* Basic parameters match, LKM is hopefully compatible.
* Cross fingers and approve.
*/
return (0);
}