diff options
Diffstat (limited to 'sys/kern/kern_linker.c')
| -rw-r--r-- | sys/kern/kern_linker.c | 1016 |
1 files changed, 1016 insertions, 0 deletions
diff --git a/sys/kern/kern_linker.c b/sys/kern/kern_linker.c new file mode 100644 index 0000000..97def9f --- /dev/null +++ b/sys/kern/kern_linker.c @@ -0,0 +1,1016 @@ +/*- + * Copyright (c) 1997 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. + * + * $Id: kern_linker.c,v 1.20 1999/01/19 16:26:32 peter Exp $ + */ + +#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 <machine/cpu.h> +#include <machine/bootinfo.h> +#include <sys/module.h> +#include <sys/linker.h> +#include <sys/unistd.h> +#include <sys/fcntl.h> +#include <sys/libkern.h> +#include <sys/namei.h> +#include <sys/vnode.h> +#include <sys/sysctl.h> + +#ifdef KLD_DEBUG +int kld_debug = 0; +#endif + +MALLOC_DEFINE(M_LINKER, "kld", "kernel linker"); +linker_file_t linker_current_file; +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 files; +static int next_file_id = 1; + +static void +linker_init(void* arg) +{ + lockinit(&lock, PVM, "klink", 0, 0); + TAILQ_INIT(&classes); + TAILQ_INIT(&files); +} + +SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); + +int +linker_add_class(const char* desc, void* priv, + struct linker_class_ops* ops) +{ + linker_class_t lc; + + lc = malloc(sizeof(struct linker_class), M_LINKER, M_NOWAIT); + if (!lc) + return ENOMEM; + bzero(lc, sizeof(*lc)); + + lc->desc = desc; + lc->priv = priv; + lc->ops = ops; + TAILQ_INSERT_HEAD(&classes, lc, link); + + return 0; +} + +static void +linker_file_sysinit(linker_file_t lf) +{ + struct linker_set* sysinits; + struct sysinit** sipp; + struct sysinit** xipp; + struct sysinit* save; + moduledata_t *moddata; + + KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", + lf->filename)); + + sysinits = (struct linker_set*) + linker_file_lookup_symbol(lf, "sysinit_set", 0); + + KLD_DPF(FILE, ("linker_file_sysinit: SYSINITs %p\n", sysinits)); + if (!sysinits) + return; + + /* HACK ALERT! */ + for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { + if ((*sipp)->func == module_register_init) { + moddata = (*sipp)->udata; + moddata->_file = lf; + } + } + + /* + * 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 = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { + for (xipp = sipp + 1; *xipp; 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 = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { + if ((*sipp)->subsystem == SI_SUB_DUMMY) + continue; /* skip dummy task(s)*/ + + switch ((*sipp)->type) { + case SI_TYPE_DEFAULT: + /* no special processing*/ + (*((*sipp)->func))((*sipp)->udata); + break; + + case SI_TYPE_KTHREAD: +#if !defined(SMP) + /* kernel thread*/ + if (fork1(&proc0, RFFDG|RFPROC|RFMEM)) + panic("fork kernel thread"); + cpu_set_fork_handler(pfind(proc0.p_retval[0]), + (*sipp)->func, (*sipp)->udata); + break; +#endif + + case SI_TYPE_KPROCESS: + /* kernel thread*/ + if (fork1(&proc0, RFFDG|RFPROC)) + panic("fork kernel process"); + cpu_set_fork_handler(pfind(proc0.p_retval[0]), + (*sipp)->func, (*sipp)->udata); + break; + + default: + panic ("linker_file_sysinit: unrecognized init type"); + } + } +} + +static void +linker_file_sysuninit(linker_file_t lf) +{ + struct linker_set* sysuninits; + struct sysinit** sipp; + struct sysinit** xipp; + struct sysinit* save; + + KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", + lf->filename)); + + sysuninits = (struct linker_set*) + linker_file_lookup_symbol(lf, "sysuninit_set", 0); + + KLD_DPF(FILE, ("linker_file_sysuninit: SYSUNINITs %p\n", sysuninits)); + if (!sysuninits) + 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 = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { + for (xipp = sipp + 1; *xipp; 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 = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { + if ((*sipp)->subsystem == SI_SUB_DUMMY) + continue; /* skip dummy task(s)*/ + + switch ((*sipp)->type) { + case SI_TYPE_DEFAULT: + /* no special processing*/ + (*((*sipp)->func))((*sipp)->udata); + break; + + default: + panic("linker_file_sysuninit: unrecognized uninit type"); + } + } +} + +int +linker_load_file(const char* filename, linker_file_t* result) +{ + linker_class_t lc; + linker_file_t lf; + int foundfile, error = 0; + char *koname = NULL; + + 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; + } + + koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); + if (koname == NULL) { + error = ENOMEM; + goto out; + } + sprintf(koname, "%s.ko", filename); + lf = NULL; + foundfile = 0; + for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { + KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", + filename, lc->desc)); + + error = lc->ops->load_file(koname, &lf); /* First with .ko */ + if (lf == NULL && error == ENOENT) + error = lc->ops->load_file(filename, &lf); /* Then try without */ + /* + * 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_sysinit(lf); + + *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: + if (koname) + free(koname, M_LINKER); + return error; +} + +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, curproc); + for (lf = TAILQ_FIRST(&files); lf; lf = TAILQ_NEXT(lf, link)) { + if (!strcmp(lf->filename, koname)) + break; + if (!strcmp(lf->filename, filename)) + break; + } + lockmgr(&lock, LK_RELEASE, 0, curproc); + +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, curproc); + for (lf = TAILQ_FIRST(&files); lf; lf = TAILQ_NEXT(lf, link)) + if (lf->id == fileid) + break; + lockmgr(&lock, LK_RELEASE, 0, curproc); + + return lf; +} + +linker_file_t +linker_make_file(const char* pathname, void* priv, struct linker_file_ops* ops) +{ + linker_file_t lf = 0; + int namelen; + const char *filename; + + filename = rindex(pathname, '/'); + if (filename && filename[1]) + filename++; + else + filename = pathname; + + KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); + lockmgr(&lock, LK_EXCLUSIVE|LK_RETRY, 0, curproc); + namelen = strlen(filename) + 1; + lf = malloc(sizeof(struct linker_file) + namelen, M_LINKER, M_WAITOK); + if (!lf) + goto out; + bzero(lf, sizeof(*lf)); + + lf->refs = 1; + lf->userrefs = 0; + lf->filename = (char*) (lf + 1); + strcpy(lf->filename, filename); + lf->id = next_file_id++; + lf->ndeps = 0; + lf->deps = NULL; + STAILQ_INIT(&lf->common); + TAILQ_INIT(&lf->modules); + + lf->priv = priv; + lf->ops = ops; + TAILQ_INSERT_TAIL(&files, lf, link); + +out: + lockmgr(&lock, LK_RELEASE, 0, curproc); + return lf; +} + +int +linker_file_unload(linker_file_t file) +{ + module_t mod, next; + struct common_symbol* cp; + int error = 0; + int i; + + KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); + lockmgr(&lock, LK_EXCLUSIVE|LK_RETRY, 0, curproc); + 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)) { + KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", + mod)); + lockmgr(&lock, LK_RELEASE, 0, curproc); + goto out; + } + + module_release(mod); + } + } + + file->refs--; + if (file->refs > 0) { + lockmgr(&lock, LK_RELEASE, 0, curproc); + goto out; + } + + linker_file_sysuninit(file); + + TAILQ_REMOVE(&files, file, link); + lockmgr(&lock, LK_RELEASE, 0, curproc); + + for (i = 0; i < file->ndeps; i++) + linker_file_unload(file->deps[i]); + free(file->deps, M_LINKER); + + for (cp = STAILQ_FIRST(&file->common); cp; + cp = STAILQ_FIRST(&file->common)) { + STAILQ_REMOVE(&file->common, cp, common_symbol, link); + free(cp, M_LINKER); + } + + file->ops->unload(file); + free(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); + if (newdeps == NULL) + return ENOMEM; + bzero(newdeps, (file->ndeps + 1) * sizeof(linker_file_t*)); + + 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; +} + +caddr_t +linker_file_lookup_symbol(linker_file_t file, const char* name, int deps) +{ + linker_sym_t sym; + linker_symval_t symval; + linker_file_t lf; + 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 (file->ops->lookup_symbol(file, name, &sym) == 0) { + file->ops->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 we have not found it in the dependencies, search globally */ + for (lf = TAILQ_FIRST(&files); lf; lf = TAILQ_NEXT(lf, link)) { + /* But skip the current file if it's on the list */ + if (lf == file) + continue; + /* And skip the files we searched above */ + for (i = 0; i < file->ndeps; i++) + if (lf == file->deps[i]) + break; + if (i < file->ndeps) + continue; + address = linker_file_lookup_symbol(lf, name, 0); + if (address) { + KLD_DPF(SYM, ("linker_file_lookup_symbol: global 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; + + for (cp = STAILQ_FIRST(&file->common); cp; + cp = STAILQ_NEXT(cp, 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); + if (!cp) { + KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); + return 0; + } + bzero(cp, sizeof(struct common_symbol) + common_size + strlen(name)+ 1); + + 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(char *symstr, linker_sym_t *sym) +{ + linker_file_t lf; + + for (lf = TAILQ_FIRST(&files); lf; lf = TAILQ_NEXT(lf, link)) { + if (lf->ops->lookup_symbol(lf, symstr, sym) == 0) + return 0; + } + return ENOENT; +} + +int +linker_ddb_search_symbol(caddr_t value, linker_sym_t *sym, long *diffp) +{ + linker_file_t lf; + u_long off = (u_long)value; + u_long diff, bestdiff; + linker_sym_t best; + linker_sym_t es; + + best = 0; + bestdiff = off; + for (lf = TAILQ_FIRST(&files); lf; lf = TAILQ_NEXT(lf, link)) { + if (lf->ops->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(linker_sym_t sym, linker_symval_t *symval) +{ + linker_file_t lf; + + for (lf = TAILQ_FIRST(&files); lf; lf = TAILQ_NEXT(lf, link)) { + if (lf->ops->symbol_values(lf, sym, symval) == 0) + return 0; + } + return ENOENT; +} + +#endif + +/* + * Syscalls. + */ + +int +kldload(struct proc* p, struct kldload_args* uap) +{ + char* filename = NULL, *modulename; + linker_file_t lf; + int error = 0; + + p->p_retval[0] = -1; + + if (securelevel > 0) + return EPERM; + + if (error = suser(p->p_ucred, &p->p_acflag)) + return error; + + filename = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); + if (error = copyinstr(SCARG(uap, file), filename, MAXPATHLEN, NULL)) + goto out; + + /* Can't load more than one module with the same name */ + modulename = rindex(filename, '/'); + if (modulename == NULL) + modulename = filename; + if (linker_find_file_by_name(modulename)) { + error = EEXIST; + goto out; + } + + if (error = linker_load_file(filename, &lf)) + goto out; + + lf->userrefs++; + p->p_retval[0] = lf->id; + +out: + if (filename) + free(filename, M_TEMP); + return error; +} + +int +kldunload(struct proc* p, struct kldunload_args* uap) +{ + linker_file_t lf; + int error = 0; + + if (securelevel > 0) + return EPERM; + + if (error = suser(p->p_ucred, &p->p_acflag)) + return error; + + 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("linkerunload: attempt to unload file which was not loaded by user\n"); + error = EBUSY; + goto out; + } + error = linker_file_unload(lf); + if (error) + goto out; + lf->userrefs--; + } else + error = ENOENT; + +out: + return error; +} + +int +kldfind(struct proc* p, struct kldfind_args* uap) +{ + char* filename = NULL, *modulename; + linker_file_t lf; + int error = 0; + + p->p_retval[0] = -1; + + filename = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); + if (error = copyinstr(SCARG(uap, file), filename, MAXPATHLEN, NULL)) + goto out; + + modulename = rindex(filename, '/'); + if (modulename == NULL) + modulename = filename; + + lf = linker_find_file_by_name(modulename); + if (lf) + p->p_retval[0] = lf->id; + else + error = ENOENT; + +out: + if (filename) + free(filename, M_TEMP); + return error; +} + +int +kldnext(struct proc* p, struct kldnext_args* uap) +{ + linker_file_t lf; + int error = 0; + + if (SCARG(uap, fileid) == 0) { + if (TAILQ_FIRST(&files)) + p->p_retval[0] = TAILQ_FIRST(&files)->id; + else + p->p_retval[0] = 0; + return 0; + } + + lf = linker_find_file_by_id(SCARG(uap, fileid)); + if (lf) { + if (TAILQ_NEXT(lf, link)) + p->p_retval[0] = TAILQ_NEXT(lf, link)->id; + else + p->p_retval[0] = 0; + } else + error = ENOENT; + + return error; +} + +int +kldstat(struct proc* p, struct kldstat_args* uap) +{ + linker_file_t lf; + int error = 0; + int version; + struct kld_file_stat* stat; + int namelen; + + 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))) + 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)) + goto out; + if (error = copyout(&lf->refs, &stat->refs, sizeof(int))) + goto out; + if (error = copyout(&lf->id, &stat->id, sizeof(int))) + goto out; + if (error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) + goto out; + if (error = copyout(&lf->size, &stat->size, sizeof(size_t))) + goto out; + + p->p_retval[0] = 0; + +out: + return error; +} + +int +kldfirstmod(struct proc* p, struct kldfirstmod_args* uap) +{ + linker_file_t lf; + int error = 0; + + lf = linker_find_file_by_id(SCARG(uap, fileid)); + if (lf) { + if (TAILQ_FIRST(&lf->modules)) + p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules)); + else + p->p_retval[0] = 0; + } else + error = ENOENT; + + return error; +} + +int +kldsym(struct proc *p, struct kldsym_args *uap) +{ + char *symstr = NULL; + linker_sym_t sym; + linker_symval_t symval; + linker_file_t lf; + struct kld_sym_lookup lookup; + int error = 0; + + if (error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) + 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)) + goto out; + + if (SCARG(uap, fileid) != 0) { + lf = linker_find_file_by_id(SCARG(uap, fileid)); + if (lf == NULL) { + error = ENOENT; + goto out; + } + if (lf->ops->lookup_symbol(lf, symstr, &sym) == 0 && + lf->ops->symbol_values(lf, sym, &symval) == 0) { + lookup.symvalue = (u_long)symval.value; + lookup.symsize = symval.size; + error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); + } else + error = ENOENT; + } else { + for (lf = TAILQ_FIRST(&files); lf; lf = TAILQ_NEXT(lf, link)) { + if (lf->ops->lookup_symbol(lf, symstr, &sym) == 0 && + lf->ops->symbol_values(lf, sym, &symval) == 0) { + lookup.symvalue = (u_long)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); + return error; +} + +/* + * Preloaded module support + */ + +static void +linker_preload(void* arg) +{ + caddr_t modptr; + char *modname; + char *modtype; + linker_file_t lf; + linker_class_t lc; + int error; + struct linker_set *sysinits; + struct sysinit **sipp; + moduledata_t *moddata; + + 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 = linker_find_file_by_name(modname); + if (lf) { + lf->userrefs++; + continue; + } + lf = NULL; + for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { + error = lc->ops->load_file(modname, &lf); + if (error) { + lf = NULL; + break; + } + } + if (lf) { + lf->userrefs++; + + sysinits = (struct linker_set*) + linker_file_lookup_symbol(lf, "sysinit_set", 0); + if (sysinits) { + /* HACK ALERT! + * This is to set the sysinit moduledata so that the module + * can attach itself to the correct containing file. + * The sysinit could be run at *any* time. + */ + for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { + if ((*sipp)->func == module_register_init) { + moddata = (*sipp)->udata; + moddata->_file = lf; + } + } + sysinit_add((struct sysinit **)sysinits->ls_items); + } + } + } +} + +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_path[MAXPATHLEN + 1] = "/;/boot/;/modules/"; + +SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, + sizeof(linker_path), "module load search path"); + +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); +} + +char * +linker_search_path(const char *name) +{ + struct nameidata nd; + struct proc *p = curproc; /* XXX */ + char *cp, *ep, *result; + int error; + enum vtype type; + + /* qualified at all? */ + if (index(name, '/')) + return(linker_strdup(name)); + + /* traverse the linker path */ + cp = linker_path; + for (;;) { + + /* find the end of this component */ + for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) + ; + result = malloc((strlen(name) + (ep - cp) + 1), M_LINKER, M_WAITOK); + if (result == NULL) /* actually ENOMEM */ + return(NULL); + + strncpy(result, cp, ep - cp); + strcpy(result + (ep - cp), name); + + /* + * 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, p); + error = vn_open(&nd, FREAD, 0); + if (error == 0) { + type = nd.ni_vp->v_type; + VOP_UNLOCK(nd.ni_vp, 0, p); + vn_close(nd.ni_vp, FREAD, p->p_ucred, p); + if (type == VREG) + return(result); + } + free(result, M_LINKER); + + if (*ep == 0) + break; + cp = ep + 1; + } + return(NULL); +} |
