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freebsd/sys/kern/kern_linker.c
Julian Elischer b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00

1705 lines
42 KiB
C

/*-
* Copyright (c) 1997-2000 Doug Rabson
* 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.
*
* $FreeBSD$
*/
#include "opt_ddb.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/sysproto.h>
#include <sys/sysent.h>
#include <sys/proc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/module.h>
#include <sys/linker.h>
#include <sys/fcntl.h>
#include <sys/libkern.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/sysctl.h>
#include "linker_if.h"
#ifdef KLD_DEBUG
int kld_debug = 0;
#endif
/*static char *linker_search_path(const char *name, struct mod_depend *verinfo);*/
static const char *linker_basename(const char* path);
static int linker_load_module(const char *kldname, const char *modname,
struct linker_file *parent, struct mod_depend *verinfo,
struct linker_file **lfpp);
/* Metadata from the static kernel */
SET_DECLARE(modmetadata_set, struct mod_metadata);
MALLOC_DEFINE(M_LINKER, "linker", "kernel linker");
linker_file_t linker_kernel_file;
static struct lock lock; /* lock for the file list */
static linker_class_list_t classes;
static linker_file_list_t linker_files;
static int next_file_id = 1;
/* XXX wrong name; we're looking at version provision tags here, not modules */
typedef TAILQ_HEAD(, modlist) modlisthead_t;
struct modlist {
TAILQ_ENTRY(modlist) link; /* chain together all modules */
linker_file_t container;
const char *name;
int version;
};
typedef struct modlist *modlist_t;
static modlisthead_t found_modules;
static char *
linker_strdup(const char *str)
{
char *result;
if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL)
strcpy(result, str);
return(result);
}
static void
linker_init(void* arg)
{
lockinit(&lock, PVM, "klink", 0, 0);
TAILQ_INIT(&classes);
TAILQ_INIT(&linker_files);
}
SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0);
int
linker_add_class(linker_class_t lc)
{
kobj_class_compile((kobj_class_t) lc);
TAILQ_INSERT_TAIL(&classes, lc, link);
return 0;
}
static void
linker_file_sysinit(linker_file_t lf)
{
struct sysinit** start, ** stop;
struct sysinit** sipp;
struct sysinit** xipp;
struct sysinit* save;
KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n",
lf->filename));
if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0)
return;
/*
* Perform a bubble sort of the system initialization objects by
* their subsystem (primary key) and order (secondary key).
*
* Since some things care about execution order, this is the
* operation which ensures continued function.
*/
for (sipp = start; sipp < stop; sipp++) {
for (xipp = sipp + 1; xipp < stop; xipp++) {
if ((*sipp)->subsystem < (*xipp)->subsystem ||
((*sipp)->subsystem == (*xipp)->subsystem &&
(*sipp)->order <= (*xipp)->order))
continue; /* skip*/
save = *sipp;
*sipp = *xipp;
*xipp = save;
}
}
/*
* Traverse the (now) ordered list of system initialization tasks.
* Perform each task, and continue on to the next task.
*/
for (sipp = start; sipp < stop; sipp++) {
if ((*sipp)->subsystem == SI_SUB_DUMMY)
continue; /* skip dummy task(s)*/
/* Call function */
(*((*sipp)->func))((*sipp)->udata);
}
}
static void
linker_file_sysuninit(linker_file_t lf)
{
struct sysinit** start, ** stop;
struct sysinit** sipp;
struct sysinit** xipp;
struct sysinit* save;
KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n",
lf->filename));
if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, NULL) != 0)
return;
/*
* Perform a reverse bubble sort of the system initialization objects
* by their subsystem (primary key) and order (secondary key).
*
* Since some things care about execution order, this is the
* operation which ensures continued function.
*/
for (sipp = start; sipp < stop; sipp++) {
for (xipp = sipp + 1; xipp < stop; xipp++) {
if ((*sipp)->subsystem > (*xipp)->subsystem ||
((*sipp)->subsystem == (*xipp)->subsystem &&
(*sipp)->order >= (*xipp)->order))
continue; /* skip*/
save = *sipp;
*sipp = *xipp;
*xipp = save;
}
}
/*
* Traverse the (now) ordered list of system initialization tasks.
* Perform each task, and continue on to the next task.
*/
for (sipp = start; sipp < stop; sipp++) {
if ((*sipp)->subsystem == SI_SUB_DUMMY)
continue; /* skip dummy task(s)*/
/* Call function */
(*((*sipp)->func))((*sipp)->udata);
}
}
static void
linker_file_register_sysctls(linker_file_t lf)
{
struct sysctl_oid **start, **stop, **oidp;
KLD_DPF(FILE, ("linker_file_register_sysctls: registering SYSCTLs for %s\n",
lf->filename));
if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
return;
for (oidp = start; oidp < stop; oidp++)
sysctl_register_oid(*oidp);
}
static void
linker_file_unregister_sysctls(linker_file_t lf)
{
struct sysctl_oid **start, **stop, **oidp;
KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs for %s\n",
lf->filename));
if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
return;
for (oidp = start; oidp < stop; oidp++)
sysctl_unregister_oid(*oidp);
}
static int
linker_file_register_modules(linker_file_t lf)
{
int error;
struct mod_metadata **start, **stop;
struct mod_metadata **mdp;
const moduledata_t *moddata;
KLD_DPF(FILE, ("linker_file_register_modules: registering modules in %s\n",
lf->filename));
if (linker_file_lookup_set(lf, "modmetadata_set", &start, &stop, 0) != 0) {
/*
* This fallback should be unnecessary, but if we get booted from
* boot2 instead of loader and we are missing our metadata then
* we have to try the best we can.
*/
if (lf == linker_kernel_file) {
start = SET_BEGIN(modmetadata_set);
stop = SET_LIMIT(modmetadata_set);
} else {
return 0;
}
}
for (mdp = start; mdp < stop; mdp++) {
if ((*mdp)->md_type != MDT_MODULE)
continue;
moddata = (*mdp)->md_data;
KLD_DPF(FILE, ("Registering module %s in %s\n",
moddata->name, lf->filename));
if (module_lookupbyname(moddata->name) != NULL) {
printf("Warning: module %s already exists\n", moddata->name);
continue; /* or return a error ? */
}
error = module_register(moddata, lf);
if (error)
printf("Module %s failed to register: %d\n", moddata->name, error);
}
return 0;
}
static void
linker_init_kernel_modules(void)
{
linker_file_register_modules(linker_kernel_file);
}
SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0);
int
linker_load_file(const char* filename, linker_file_t* result)
{
linker_class_t lc;
linker_file_t lf;
int foundfile, error = 0;
/* Refuse to load modules if securelevel raised */
if (securelevel > 0)
return EPERM;
lf = linker_find_file_by_name(filename);
if (lf) {
KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename));
*result = lf;
lf->refs++;
goto out;
}
lf = NULL;
foundfile = 0;
TAILQ_FOREACH(lc, &classes, link) {
KLD_DPF(FILE, ("linker_load_file: trying to load %s\n",
filename));
error = LINKER_LOAD_FILE(lc, filename, &lf);
/*
* If we got something other than ENOENT, then it exists but we cannot
* load it for some other reason.
*/
if (error != ENOENT)
foundfile = 1;
if (lf) {
linker_file_register_modules(lf);
linker_file_register_sysctls(lf);
linker_file_sysinit(lf);
lf->flags |= LINKER_FILE_LINKED;
*result = lf;
error = 0;
goto out;
}
}
/*
* Less than ideal, but tells the user whether it failed to load or
* the module was not found.
*/
if (foundfile)
error = ENOEXEC; /* Format not recognised (or unloadable) */
else
error = ENOENT; /* Nothing found */
out:
return error;
}
/* XXX: function parameters are incomplete */
int
linker_reference_module(const char *modname, linker_file_t *result)
{
return linker_load_module(NULL, modname, NULL, NULL, result);
}
linker_file_t
linker_find_file_by_name(const char* filename)
{
linker_file_t lf = 0;
char *koname;
koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK);
if (koname == NULL)
goto out;
sprintf(koname, "%s.ko", filename);
lockmgr(&lock, LK_SHARED, 0, curthread);
TAILQ_FOREACH(lf, &linker_files, link) {
if (!strcmp(lf->filename, koname))
break;
if (!strcmp(lf->filename, filename))
break;
}
lockmgr(&lock, LK_RELEASE, 0, curthread);
out:
if (koname)
free(koname, M_LINKER);
return lf;
}
linker_file_t
linker_find_file_by_id(int fileid)
{
linker_file_t lf = 0;
lockmgr(&lock, LK_SHARED, 0, curthread);
TAILQ_FOREACH(lf, &linker_files, link)
if (lf->id == fileid)
break;
lockmgr(&lock, LK_RELEASE, 0, curthread);
return lf;
}
linker_file_t
linker_make_file(const char* pathname, linker_class_t lc)
{
linker_file_t lf = 0;
const char *filename;
filename = linker_basename(pathname);
KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename));
lockmgr(&lock, LK_EXCLUSIVE, 0, curthread);
lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK);
if (!lf)
goto out;
lf->refs = 1;
lf->userrefs = 0;
lf->flags = 0;
lf->filename = linker_strdup(filename);
lf->id = next_file_id++;
lf->ndeps = 0;
lf->deps = NULL;
STAILQ_INIT(&lf->common);
TAILQ_INIT(&lf->modules);
TAILQ_INSERT_TAIL(&linker_files, lf, link);
out:
lockmgr(&lock, LK_RELEASE, 0, curthread);
return lf;
}
int
linker_file_unload(linker_file_t file)
{
module_t mod, next;
modlist_t ml, nextml;
struct common_symbol* cp;
int error = 0;
int i;
/* Refuse to unload modules if securelevel raised */
if (securelevel > 0)
return EPERM;
KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs));
lockmgr(&lock, LK_EXCLUSIVE, 0, curthread);
if (file->refs == 1) {
KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n"));
/*
* Inform any modules associated with this file.
*/
for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {
next = module_getfnext(mod);
/*
* Give the module a chance to veto the unload.
*/
if ((error = module_unload(mod)) != 0) {
KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n",
mod));
lockmgr(&lock, LK_RELEASE, 0, curthread);
goto out;
}
module_release(mod);
}
}
file->refs--;
if (file->refs > 0) {
lockmgr(&lock, LK_RELEASE, 0, curthread);
goto out;
}
for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) {
nextml = TAILQ_NEXT(ml, link);
if (ml->container == file) {
TAILQ_REMOVE(&found_modules, ml, link);
}
}
/* Don't try to run SYSUNINITs if we are unloaded due to a link error */
if (file->flags & LINKER_FILE_LINKED) {
linker_file_sysuninit(file);
linker_file_unregister_sysctls(file);
}
TAILQ_REMOVE(&linker_files, file, link);
lockmgr(&lock, LK_RELEASE, 0, curthread);
if (file->deps) {
for (i = 0; i < file->ndeps; i++)
linker_file_unload(file->deps[i]);
free(file->deps, M_LINKER);
file->deps = NULL;
}
for (cp = STAILQ_FIRST(&file->common); cp;
cp = STAILQ_FIRST(&file->common)) {
STAILQ_REMOVE(&file->common, cp, common_symbol, link);
free(cp, M_LINKER);
}
LINKER_UNLOAD(file);
if (file->filename) {
free(file->filename, M_LINKER);
file->filename = NULL;
}
kobj_delete((kobj_t) file, M_LINKER);
out:
return error;
}
int
linker_file_add_dependancy(linker_file_t file, linker_file_t dep)
{
linker_file_t* newdeps;
newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*),
M_LINKER, M_WAITOK | M_ZERO);
if (newdeps == NULL)
return ENOMEM;
if (file->deps) {
bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*));
free(file->deps, M_LINKER);
}
file->deps = newdeps;
file->deps[file->ndeps] = dep;
file->ndeps++;
return 0;
}
/*
* Locate a linker set and its contents.
* This is a helper function to avoid linker_if.h exposure elsewhere.
* Note: firstp and lastp are really void ***
*/
int
linker_file_lookup_set(linker_file_t file, const char *name,
void *firstp, void *lastp, int *countp)
{
return LINKER_LOOKUP_SET(file, name, firstp, lastp, countp);
}
caddr_t
linker_file_lookup_symbol(linker_file_t file, const char* name, int deps)
{
c_linker_sym_t sym;
linker_symval_t symval;
caddr_t address;
size_t common_size = 0;
int i;
KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n",
file, name, deps));
if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) {
LINKER_SYMBOL_VALUES(file, sym, &symval);
if (symval.value == 0)
/*
* For commons, first look them up in the dependancies and
* only allocate space if not found there.
*/
common_size = symval.size;
else {
KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value));
return symval.value;
}
}
if (deps) {
for (i = 0; i < file->ndeps; i++) {
address = linker_file_lookup_symbol(file->deps[i], name, 0);
if (address) {
KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address));
return address;
}
}
}
if (common_size > 0) {
/*
* This is a common symbol which was not found in the
* dependancies. We maintain a simple common symbol table in
* the file object.
*/
struct common_symbol* cp;
STAILQ_FOREACH(cp, &file->common, link)
if (!strcmp(cp->name, name)) {
KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address));
return cp->address;
}
/*
* Round the symbol size up to align.
*/
common_size = (common_size + sizeof(int) - 1) & -sizeof(int);
cp = malloc(sizeof(struct common_symbol)
+ common_size
+ strlen(name) + 1,
M_LINKER, M_WAITOK | M_ZERO);
if (!cp) {
KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n"));
return 0;
}
cp->address = (caddr_t) (cp + 1);
cp->name = cp->address + common_size;
strcpy(cp->name, name);
bzero(cp->address, common_size);
STAILQ_INSERT_TAIL(&file->common, cp, link);
KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address));
return cp->address;
}
KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n"));
return 0;
}
#ifdef DDB
/*
* DDB Helpers. DDB has to look across multiple files with their own
* symbol tables and string tables.
*
* Note that we do not obey list locking protocols here. We really don't
* need DDB to hang because somebody's got the lock held. We'll take the
* chance that the files list is inconsistant instead.
*/
int
linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym)
{
linker_file_t lf;
TAILQ_FOREACH(lf, &linker_files, link) {
if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0)
return 0;
}
return ENOENT;
}
int
linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
{
linker_file_t lf;
u_long off = (uintptr_t)value;
u_long diff, bestdiff;
c_linker_sym_t best;
c_linker_sym_t es;
best = 0;
bestdiff = off;
TAILQ_FOREACH(lf, &linker_files, link) {
if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0)
continue;
if (es != 0 && diff < bestdiff) {
best = es;
bestdiff = diff;
}
if (bestdiff == 0)
break;
}
if (best) {
*sym = best;
*diffp = bestdiff;
return 0;
} else {
*sym = 0;
*diffp = off;
return ENOENT;
}
}
int
linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
{
linker_file_t lf;
TAILQ_FOREACH(lf, &linker_files, link) {
if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0)
return 0;
}
return ENOENT;
}
#endif
/*
* Syscalls.
*/
/*
* MPSAFE
*/
int
kldload(struct thread* td, struct kldload_args* uap)
{
char *kldname, *modname;
char *pathname = NULL;
linker_file_t lf;
int error = 0;
td->td_retval[0] = -1;
if (securelevel > 0) /* redundant, but that's OK */
return EPERM;
mtx_lock(&Giant);
if ((error = suser_td(td)) != 0)
goto out;
pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0)
goto out;
/*
* If path do not contain qualified name or any dot in it (kldname.ko, or
* kldname.ver.ko) treat it as interface name.
*/
if (index(pathname, '/') || index(pathname, '.')) {
kldname = pathname;
modname = NULL;
} else {
kldname = NULL;
modname = pathname;
}
error = linker_load_module(kldname, modname, NULL, NULL, &lf);
if (error)
goto out;
lf->userrefs++;
td->td_retval[0] = lf->id;
out:
if (pathname)
free(pathname, M_TEMP);
mtx_unlock(&Giant);
return (error);
}
/*
* MPSAFE
*/
int
kldunload(struct thread* td, struct kldunload_args* uap)
{
linker_file_t lf;
int error = 0;
if (securelevel > 0) /* redundant, but that's OK */
return EPERM;
mtx_lock(&Giant);
if ((error = suser_td(td)) != 0)
goto out;
lf = linker_find_file_by_id(SCARG(uap, fileid));
if (lf) {
KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
if (lf->userrefs == 0) {
printf("kldunload: attempt to unload file that was loaded by the kernel\n");
error = EBUSY;
goto out;
}
lf->userrefs--;
error = linker_file_unload(lf);
if (error)
lf->userrefs++;
} else {
error = ENOENT;
}
out:
mtx_unlock(&Giant);
return (error);
}
/*
* MPSAFE
*/
int
kldfind(struct thread* td, struct kldfind_args* uap)
{
char* pathname;
const char *filename;
linker_file_t lf;
int error = 0;
mtx_lock(&Giant);
td->td_retval[0] = -1;
pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0)
goto out;
filename = linker_basename(pathname);
lf = linker_find_file_by_name(filename);
if (lf)
td->td_retval[0] = lf->id;
else
error = ENOENT;
out:
if (pathname)
free(pathname, M_TEMP);
mtx_unlock(&Giant);
return (error);
}
/*
* MPSAFE
*/
int
kldnext(struct thread* td, struct kldnext_args* uap)
{
linker_file_t lf;
int error = 0;
mtx_lock(&Giant);
if (SCARG(uap, fileid) == 0) {
if (TAILQ_FIRST(&linker_files))
td->td_retval[0] = TAILQ_FIRST(&linker_files)->id;
else
td->td_retval[0] = 0;
goto out;
}
lf = linker_find_file_by_id(SCARG(uap, fileid));
if (lf) {
if (TAILQ_NEXT(lf, link))
td->td_retval[0] = TAILQ_NEXT(lf, link)->id;
else
td->td_retval[0] = 0;
} else {
error = ENOENT;
}
out:
mtx_unlock(&Giant);
return (error);
}
/*
* MPSAFE
*/
int
kldstat(struct thread* td, struct kldstat_args* uap)
{
linker_file_t lf;
int error = 0;
int version;
struct kld_file_stat* stat;
int namelen;
mtx_lock(&Giant);
lf = linker_find_file_by_id(SCARG(uap, fileid));
if (!lf) {
error = ENOENT;
goto out;
}
stat = SCARG(uap, stat);
/*
* Check the version of the user's structure.
*/
if ((error = copyin(&stat->version, &version, sizeof(version))) != 0)
goto out;
if (version != sizeof(struct kld_file_stat)) {
error = EINVAL;
goto out;
}
namelen = strlen(lf->filename) + 1;
if (namelen > MAXPATHLEN)
namelen = MAXPATHLEN;
if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0)
goto out;
if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0)
goto out;
if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0)
goto out;
if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0)
goto out;
if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0)
goto out;
td->td_retval[0] = 0;
out:
mtx_unlock(&Giant);
return (error);
}
/*
* MPSAFE
*/
int
kldfirstmod(struct thread* td, struct kldfirstmod_args* uap)
{
linker_file_t lf;
int error = 0;
mtx_lock(&Giant);
lf = linker_find_file_by_id(SCARG(uap, fileid));
if (lf) {
if (TAILQ_FIRST(&lf->modules))
td->td_retval[0] = module_getid(TAILQ_FIRST(&lf->modules));
else
td->td_retval[0] = 0;
} else {
error = ENOENT;
}
mtx_unlock(&Giant);
return (error);
}
/*
* MPSAFE
*/
int
kldsym(struct thread *td, struct kldsym_args *uap)
{
char *symstr = NULL;
c_linker_sym_t sym;
linker_symval_t symval;
linker_file_t lf;
struct kld_sym_lookup lookup;
int error = 0;
mtx_lock(&Giant);
if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0)
goto out;
if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) {
error = EINVAL;
goto out;
}
symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0)
goto out;
if (SCARG(uap, fileid) != 0) {
lf = linker_find_file_by_id(SCARG(uap, fileid));
if (lf == NULL) {
error = ENOENT;
goto out;
}
if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
lookup.symvalue = (uintptr_t)symval.value;
lookup.symsize = symval.size;
error = copyout(&lookup, SCARG(uap, data), sizeof(lookup));
} else
error = ENOENT;
} else {
TAILQ_FOREACH(lf, &linker_files, link) {
if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
lookup.symvalue = (uintptr_t)symval.value;
lookup.symsize = symval.size;
error = copyout(&lookup, SCARG(uap, data), sizeof(lookup));
break;
}
}
if (!lf)
error = ENOENT;
}
out:
if (symstr)
free(symstr, M_TEMP);
mtx_unlock(&Giant);
return (error);
}
/*
* Preloaded module support
*/
static modlist_t
modlist_lookup(const char *name, int ver)
{
modlist_t mod;
TAILQ_FOREACH(mod, &found_modules, link) {
if (strcmp(mod->name, name) == 0 && (ver == 0 || mod->version == ver))
return mod;
}
return NULL;
}
static modlist_t
modlist_lookup2(const char *name, struct mod_depend *verinfo)
{
modlist_t mod, bestmod;
int ver;
if (verinfo == NULL)
return modlist_lookup(name, 0);
bestmod = NULL;
for (mod = TAILQ_FIRST(&found_modules); mod; mod = TAILQ_NEXT(mod, link)) {
if (strcmp(mod->name, name) != 0)
continue;
ver = mod->version;
if (ver == verinfo->md_ver_preferred)
return mod;
if (ver >= verinfo->md_ver_minimum &&
ver <= verinfo->md_ver_maximum &&
ver > bestmod->version)
bestmod = mod;
}
return bestmod;
}
static modlist_t
modlist_newmodule(const char *modname, int version, linker_file_t container)
{
modlist_t mod;
mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT);
if (mod == NULL)
panic("no memory for module list");
bzero(mod, sizeof(*mod));
mod->container = container;
mod->name = modname;
mod->version = version;
TAILQ_INSERT_TAIL(&found_modules, mod, link);
return mod;
}
/*
* This routine is cheap and nasty but will work for data pointers.
*/
static void *
linker_reloc_ptr(linker_file_t lf, const void *offset)
{
return lf->address + (uintptr_t)offset;
}
/*
* Dereference MDT_VERSION metadata into module name and version
*/
static void
linker_mdt_version(linker_file_t lf, struct mod_metadata *mp,
const char **modname, int *version)
{
struct mod_version *mvp;
if (modname)
*modname = linker_reloc_ptr(lf, mp->md_cval);
if (version) {
mvp = linker_reloc_ptr(lf, mp->md_data);
*version = mvp->mv_version;
}
}
/*
* Dereference MDT_DEPEND metadata into module name and mod_depend structure
*/
static void
linker_mdt_depend(linker_file_t lf, struct mod_metadata *mp,
const char **modname, struct mod_depend **verinfo)
{
if (modname)
*modname = linker_reloc_ptr(lf, mp->md_cval);
if (verinfo)
*verinfo = linker_reloc_ptr(lf, mp->md_data);
}
static void
linker_addmodules(linker_file_t lf, struct mod_metadata **start,
struct mod_metadata **stop, int preload)
{
struct mod_metadata *mp, **mdp;
const char *modname;
int ver;
for (mdp = start; mdp < stop; mdp++) {
if (preload)
mp = *mdp;
else
mp = linker_reloc_ptr(lf, *mdp);
if (mp->md_type != MDT_VERSION)
continue;
if (preload) {
modname = mp->md_cval;
ver = ((struct mod_version*)mp->md_data)->mv_version;
} else
linker_mdt_version(lf, mp, &modname, &ver);
if (modlist_lookup(modname, ver) != NULL) {
printf("module %s already present!\n", modname);
/* XXX what can we do? this is a build error. :-( */
continue;
}
modlist_newmodule(modname, ver, lf);
}
}
static void
linker_preload(void* arg)
{
caddr_t modptr;
const char *modname, *nmodname;
char *modtype;
linker_file_t lf;
linker_class_t lc;
int error;
linker_file_list_t loaded_files;
linker_file_list_t depended_files;
struct mod_metadata *mp, *nmp;
struct mod_metadata **start, **stop, **mdp, **nmdp;
struct mod_depend *verinfo;
int nver;
int resolves;
modlist_t mod;
struct sysinit **si_start, **si_stop;
TAILQ_INIT(&loaded_files);
TAILQ_INIT(&depended_files);
TAILQ_INIT(&found_modules);
error = 0;
modptr = NULL;
while ((modptr = preload_search_next_name(modptr)) != NULL) {
modname = (char *)preload_search_info(modptr, MODINFO_NAME);
modtype = (char *)preload_search_info(modptr, MODINFO_TYPE);
if (modname == NULL) {
printf("Preloaded module at %p does not have a name!\n", modptr);
continue;
}
if (modtype == NULL) {
printf("Preloaded module at %p does not have a type!\n", modptr);
continue;
}
printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr);
lf = NULL;
TAILQ_FOREACH(lc, &classes, link) {
error = LINKER_LINK_PRELOAD(lc, modname, &lf);
if (error) {
lf = NULL;
break;
}
}
if (lf)
TAILQ_INSERT_TAIL(&loaded_files, lf, loaded);
}
/*
* First get a list of stuff in the kernel.
*/
if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, &stop,
NULL) == 0)
linker_addmodules(linker_kernel_file, start, stop, 1);
/*
* this is a once-off kinky bubble sort
* resolve relocation dependency requirements
*/
restart:
TAILQ_FOREACH(lf, &loaded_files, loaded) {
error = linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL);
/*
* First, look to see if we would successfully link with this stuff.
*/
resolves = 1; /* unless we know otherwise */
if (!error) {
for (mdp = start; mdp < stop; mdp++) {
mp = linker_reloc_ptr(lf, *mdp);
if (mp->md_type != MDT_DEPEND)
continue;
linker_mdt_depend(lf, mp, &modname, &verinfo);
for (nmdp = start; nmdp < stop; nmdp++) {
nmp = linker_reloc_ptr(lf, *nmdp);
if (nmp->md_type != MDT_VERSION)
continue;
linker_mdt_version(lf, nmp, &nmodname, NULL);
nmodname = linker_reloc_ptr(lf, nmp->md_cval);
if (strcmp(modname, nmodname) == 0)
break;
}
if (nmdp < stop) /* it's a self reference */
continue;
if (modlist_lookup2(modname, verinfo) == NULL) {
/* ok, the module isn't here yet, we are not finished */
resolves = 0;
}
}
}
/*
* OK, if we found our modules, we can link. So, "provide" the
* modules inside and add it to the end of the link order list.
*/
if (resolves) {
if (!error) {
for (mdp = start; mdp < stop; mdp++) {
mp = linker_reloc_ptr(lf, *mdp);
if (mp->md_type != MDT_VERSION)
continue;
linker_mdt_version(lf, mp, &modname, &nver);
if (modlist_lookup(modname, nver) != NULL) {
printf("module %s already present!\n", modname);
linker_file_unload(lf);
TAILQ_REMOVE(&loaded_files, lf, loaded);
goto restart; /* we changed the tailq next ptr */
}
modlist_newmodule(modname, nver, lf);
}
}
TAILQ_REMOVE(&loaded_files, lf, loaded);
TAILQ_INSERT_TAIL(&depended_files, lf, loaded);
/*
* Since we provided modules, we need to restart the sort so
* that the previous files that depend on us have a chance.
* Also, we've busted the tailq next pointer with the REMOVE.
*/
goto restart;
}
}
/*
* At this point, we check to see what could not be resolved..
*/
TAILQ_FOREACH(lf, &loaded_files, loaded) {
printf("KLD file %s is missing dependencies\n", lf->filename);
linker_file_unload(lf);
TAILQ_REMOVE(&loaded_files, lf, loaded);
}
/*
* We made it. Finish off the linking in the order we determined.
*/
TAILQ_FOREACH(lf, &depended_files, loaded) {
if (linker_kernel_file) {
linker_kernel_file->refs++;
error = linker_file_add_dependancy(lf, linker_kernel_file);
if (error)
panic("cannot add dependency");
}
lf->userrefs++; /* so we can (try to) kldunload it */
error = linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL);
if (!error) {
for (mdp = start; mdp < stop; mdp++) {
mp = linker_reloc_ptr(lf, *mdp);
if (mp->md_type != MDT_DEPEND)
continue;
linker_mdt_depend(lf, mp, &modname, &verinfo);
mod = modlist_lookup2(modname, verinfo);
mod->container->refs++;
error = linker_file_add_dependancy(lf, mod->container);
if (error)
panic("cannot add dependency");
}
}
/*
* Now do relocation etc using the symbol search paths established by
* the dependencies
*/
error = LINKER_LINK_PRELOAD_FINISH(lf);
if (error) {
printf("KLD file %s - could not finalize loading\n", lf->filename);
linker_file_unload(lf);
continue;
}
linker_file_register_modules(lf);
if (linker_file_lookup_set(lf, "sysinit_set", &si_start, &si_stop, NULL) == 0)
sysinit_add(si_start, si_stop);
linker_file_register_sysctls(lf);
lf->flags |= LINKER_FILE_LINKED;
}
/* woohoo! we made it! */
}
SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0);
/*
* Search for a not-loaded module by name.
*
* Modules may be found in the following locations:
*
* - preloaded (result is just the module name)
* - on disk (result is full path to module)
*
* If the module name is qualified in any way (contains path, etc.)
* the we simply return a copy of it.
*
* The search path can be manipulated via sysctl. Note that we use the ';'
* character as a separator to be consistent with the bootloader.
*/
static char linker_hintfile[] = "linker.hints";
static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules;/modules";
SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path,
sizeof(linker_path), "module load search path");
TUNABLE_STR("module_path", linker_path, sizeof(linker_path));
static char *linker_ext_list[] = {
"",
".ko",
NULL
};
/*
* Check if file actually exists either with or without extension listed
* in the linker_ext_list.
* (probably should be generic for the rest of the kernel)
*/
static char *
linker_lookup_file(const char *path, int pathlen,
const char *name, int namelen, struct vattr *vap)
{
struct nameidata nd;
struct thread *td = curthread; /* XXX */
char *result, **cpp, *sep;
int error, len, extlen, reclen, flags;
enum vtype type;
extlen = 0;
for (cpp = linker_ext_list; *cpp; cpp++) {
len = strlen(*cpp);
if (len > extlen)
extlen = len;
}
extlen++; /* trailing '\0' */
sep = (path[pathlen - 1] != '/') ? "/" : "";
reclen = pathlen + strlen(sep) + namelen + extlen + 1;
result = malloc(reclen, M_LINKER, M_WAITOK);
for (cpp = linker_ext_list; *cpp; cpp++) {
snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep,
namelen, name, *cpp);
/*
* Attempt to open the file, and return the path if we succeed
* and it's a regular file.
*/
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td);
flags = FREAD;
error = vn_open(&nd, &flags, 0);
if (error == 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
type = nd.ni_vp->v_type;
if (vap)
VOP_GETATTR(nd.ni_vp, vap, td->td_proc->p_ucred, td);
VOP_UNLOCK(nd.ni_vp, 0, td);
vn_close(nd.ni_vp, FREAD, td->td_proc->p_ucred, td);
if (type == VREG)
return(result);
}
}
free(result, M_LINKER);
return(NULL);
}
#define INT_ALIGN(base, ptr) ptr = \
(base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1))
/*
* Lookup KLD which contains requested module in the "linker.hints" file.
* If version specification is available, then try to find the best KLD.
* Otherwise just find the latest one.
*/
static char *
linker_hints_lookup(const char *path, int pathlen,
const char *modname, int modnamelen,
struct mod_depend *verinfo)
{
struct thread *td = curthread; /* XXX */
struct ucred *cred = td ? td->td_proc->p_ucred : NULL;
struct nameidata nd;
struct vattr vattr, mattr;
u_char *hints = NULL;
u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep;
int error, ival, bestver, *intp, reclen, found, flags, clen, blen;
result = NULL;
bestver = found = 0;
sep = (path[pathlen - 1] != '/') ? "/" : "";
reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen +
strlen(sep) + 1;
pathbuf = malloc(reclen, M_LINKER, M_WAITOK);
snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, linker_hintfile);
NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td);
flags = FREAD;
error = vn_open(&nd, &flags, 0);
if (error)
goto bad;
NDFREE(&nd, NDF_ONLY_PNBUF);
VOP_UNLOCK(nd.ni_vp, 0, td);
if (nd.ni_vp->v_type != VREG)
goto bad;
best = cp = NULL;
error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td);
if (error)
goto bad;
/*
* XXX: we need to limit this number to some reasonable value
*/
if (vattr.va_size > 100 * 1024) {
printf("hints file too large %ld\n", (long)vattr.va_size);
goto bad;
}
hints = malloc(vattr.va_size, M_TEMP, M_WAITOK);
if (hints == NULL)
goto bad;
error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0,
UIO_SYSSPACE, IO_NODELOCKED, cred, &reclen, td);
if (error)
goto bad;
vn_close(nd.ni_vp, FREAD, cred, td);
nd.ni_vp = NULL;
if (reclen != 0) {
printf("can't read %d\n", reclen);
goto bad;
}
intp = (int*)hints;
ival = *intp++;
if (ival != LINKER_HINTS_VERSION) {
printf("hints file version mismatch %d\n", ival);
goto bad;
}
bufend = hints + vattr.va_size;
recptr = (u_char*)intp;
clen = blen = 0;
while (recptr < bufend && !found) {
intp = (int*)recptr;
reclen = *intp++;
ival = *intp++;
cp = (char*)intp;
switch (ival) {
case MDT_VERSION:
clen = *cp++;
if (clen != modnamelen || bcmp(cp, modname, clen) != 0)
break;
cp += clen;
INT_ALIGN(hints, cp);
ival = *(int*)cp;
cp += sizeof(int);
clen = *cp++;
if (verinfo == NULL || ival == verinfo->md_ver_preferred) {
found = 1;
break;
}
if (ival >= verinfo->md_ver_minimum &&
ival <= verinfo->md_ver_maximum &&
ival > bestver) {
bestver = ival;
best = cp;
blen = clen;
}
break;
default:
break;
}
recptr += reclen + sizeof(int);
}
/*
* Finally check if KLD is in the place
*/
if (found)
result = linker_lookup_file(path, pathlen, cp, clen, &mattr);
else if (best)
result = linker_lookup_file(path, pathlen, best, blen, &mattr);
if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) {
/*
* KLD is newer than hints file. What we should do now ?
*/
printf("warning: KLD '%s' is newer than the linker.hints file\n",
result);
}
bad:
if (hints)
free(hints, M_TEMP);
if (nd.ni_vp != NULL)
vn_close(nd.ni_vp, FREAD, cred, td);
/*
* If nothing found or hints is absent - fallback to the old way
* by using "kldname[.ko]" as module name.
*/
if (!found && !bestver && result == NULL)
result = linker_lookup_file(path, pathlen, modname, modnamelen, NULL);
return result;
}
/*
* Lookup KLD which contains requested module in the all directories.
*/
static char *
linker_search_module(const char *modname, int modnamelen,
struct mod_depend *verinfo)
{
char *cp, *ep, *result;
/*
* traverse the linker path
*/
for (cp = linker_path; *cp; cp = ep + 1) {
/* find the end of this component */
for (ep = cp; (*ep != 0) && (*ep != ';'); ep++)
;
result = linker_hints_lookup(cp, ep - cp, modname, modnamelen, verinfo);
if (result != NULL)
return(result);
if (*ep == 0)
break;
}
return (NULL);
}
/*
* Search for module in all directories listed in the linker_path.
*/
static char *
linker_search_kld(const char *name)
{
char *cp, *ep, *result, **cpp;
int extlen, len;
/* qualified at all? */
if (index(name, '/'))
return(linker_strdup(name));
extlen = 0;
for (cpp = linker_ext_list; *cpp; cpp++) {
len = strlen(*cpp);
if (len > extlen)
extlen = len;
}
extlen++; /* trailing '\0' */
/* traverse the linker path */
len = strlen(name);
for (ep = linker_path; *ep; ep++) {
cp = ep;
/* find the end of this component */
for (; *ep != 0 && *ep != ';'; ep++)
;
result = linker_lookup_file(cp, ep - cp, name, len, NULL);
if (result != NULL)
return(result);
}
return(NULL);
}
static const char *
linker_basename(const char* path)
{
const char *filename;
filename = rindex(path, '/');
if (filename == NULL)
return path;
if (filename[1])
filename++;
return filename;
}
/*
* Find a file which contains given module and load it,
* if "parent" is not NULL, register a reference to it.
*/
static int
linker_load_module(const char *kldname, const char *modname,
struct linker_file *parent, struct mod_depend *verinfo,
struct linker_file **lfpp)
{
linker_file_t lfdep;
const char *filename;
char *pathname;
int error;
if (modname == NULL) {
/*
* We have to load KLD
*/
KASSERT(verinfo == NULL, ("linker_load_module: verinfo is not NULL"));
pathname = linker_search_kld(kldname);
} else {
if (modlist_lookup2(modname, verinfo) != NULL)
return (EEXIST);
if (kldname == NULL) {
/*
* Need to find a KLD with required module
*/
pathname = linker_search_module(modname, strlen(modname), verinfo);
} else
pathname = linker_strdup(kldname);
}
if (pathname == NULL)
return (ENOENT);
/*
* Can't load more than one file with the same basename
* XXX: Actually it should be possible to have multiple KLDs
* with the same basename but different path because they can provide
* different versions of the same modules.
*/
filename = linker_basename(pathname);
if (linker_find_file_by_name(filename)) {
error = EEXIST;
goto out;
}
do {
error = linker_load_file(pathname, &lfdep);
if (error)
break;
if (modname && verinfo && modlist_lookup2(modname, verinfo) == NULL) {
linker_file_unload(lfdep);
error = ENOENT;
break;
}
if (parent) {
error = linker_file_add_dependancy(parent, lfdep);
if (error)
break;
}
if (lfpp)
*lfpp = lfdep;
} while(0);
out:
if (pathname)
free(pathname, M_LINKER);
return error;
}
/*
* This routine is responsible for finding dependencies of userland
* initiated kldload(2)'s of files.
*/
int
linker_load_dependancies(linker_file_t lf)
{
linker_file_t lfdep;
struct mod_metadata **start, **stop, **mdp, **nmdp;
struct mod_metadata *mp, *nmp;
struct mod_depend *verinfo;
modlist_t mod;
const char *modname, *nmodname;
int ver, error = 0, count;
/*
* All files are dependant on /kernel.
*/
if (linker_kernel_file) {
linker_kernel_file->refs++;
error = linker_file_add_dependancy(lf, linker_kernel_file);
if (error)
return error;
}
if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, &count) != 0)
return 0;
for (mdp = start; mdp < stop; mdp++) {
mp = linker_reloc_ptr(lf, *mdp);
if (mp->md_type != MDT_VERSION)
continue;
linker_mdt_version(lf, mp, &modname, &ver);
mod = modlist_lookup(modname, ver);
if (mod != NULL) {
printf("interface %s.%d already present in the KLD '%s'!\n",
modname, ver, mod->container->filename);
return EEXIST;
}
}
for (mdp = start; mdp < stop; mdp++) {
mp = linker_reloc_ptr(lf, *mdp);
if (mp->md_type != MDT_DEPEND)
continue;
linker_mdt_depend(lf, mp, &modname, &verinfo);
nmodname = NULL;
for (nmdp = start; nmdp < stop; nmdp++) {
nmp = linker_reloc_ptr(lf, *nmdp);
if (nmp->md_type != MDT_VERSION)
continue;
nmodname = linker_reloc_ptr(lf, nmp->md_cval);
if (strcmp(modname, nmodname) == 0)
break;
}
if (nmdp < stop) /* early exit, it's a self reference */
continue;
mod = modlist_lookup2(modname, verinfo);
if (mod) { /* woohoo, it's loaded already */
lfdep = mod->container;
lfdep->refs++;
error = linker_file_add_dependancy(lf, lfdep);
if (error)
break;
continue;
}
error = linker_load_module(NULL, modname, lf, verinfo, NULL);
if (error) {
printf("KLD %s: depends on %s - not available\n",
lf->filename, modname);
break;
}
}
if (error)
return error;
linker_addmodules(lf, start, stop, 0);
return error;
}