From owner-freebsd-bugs Thu Jan 7 13:10:10 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id NAA07907 for freebsd-bugs-outgoing; Thu, 7 Jan 1999 13:10:10 -0800 (PST) (envelope-from owner-freebsd-bugs@FreeBSD.ORG) Received: from freefall.freebsd.org (freefall.FreeBSD.ORG [204.216.27.21]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id NAA07895 for ; Thu, 7 Jan 1999 13:10:07 -0800 (PST) (envelope-from gnats@FreeBSD.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.8.8/8.8.5) id NAA17484; Thu, 7 Jan 1999 13:10:01 -0800 (PST) Date: Thu, 7 Jan 1999 13:10:01 -0800 (PST) Message-Id: <199901072110.NAA17484@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.ORG From: Assar Westerlund Subject: Re: kern/9359: implement support for adding syscalls in KLD modules Reply-To: Assar Westerlund Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org The following reply was made to PR kern/9359; it has been noted by GNATS. From: Assar Westerlund To: Doug Rabson Cc: FreeBSD-gnats-submit@freebsd.org Subject: Re: kern/9359: implement support for adding syscalls in KLD modules Date: 07 Jan 1999 22:08:09 +0100 Doug Rabson writes: > This looks good on first reading. Could you update the syscall kld > example in share/examples/kld to use your new mechanism. Sure, or rather, I added a new one in share/examples/kld/syscall and removed the misc one. I also made a little modifications to my previous patches to be able to retrieve the allocated syscall number. I think some more general way of communicating the results of dynamically allocating device major numbers and system calls number to user-land is needed. I'm not sure how it should look like, but the `-p' option to modload was at least a beginning. /assar ---------------------------------------------------------------------- Index: share/examples/kld/Makefile =================================================================== RCS file: /src/fbsd-repository/src/share/examples/kld/Makefile,v retrieving revision 1.1 diff -u -w -r1.1 Makefile --- Makefile 1998/12/11 10:44:30 1.1 +++ Makefile 1999/01/07 19:33:33 @@ -65,6 +65,6 @@ # SUCH DAMAGE. # -SUBDIR= cdev misc +SUBDIR= cdev syscall .include --- /dev/null Thu Jan 7 21:47:47 1999 +++ share/examples/kld/syscall/Makefile Thu Jan 7 20:34:25 1999 @@ -0,0 +1,9 @@ +# Makefile for sample syscall module + +SUBDIR= module test + +load: _SUBDIRUSE + +unload: _SUBDIRUSE + +.include --- /dev/null Thu Jan 7 21:47:47 1999 +++ share/examples/kld/syscall/module/Makefile Thu Jan 7 21:49:41 1999 @@ -0,0 +1,17 @@ +# Makefile for building the sample syscall module + +SRCS = syscall.c +KMOD = syscall +KO = ${KMOD}.ko +KLDMOD = t + +KLDLOAD = /sbin/kldload +KLDUNLOAD = /sbin/kldunload + +load: ${KO} + ${KLDLOAD} -v ./${KO} + +unload: ${KO} + ${KLDUNLOAD} -v -n ${KO} + +.include --- /dev/null Thu Jan 7 21:47:47 1999 +++ share/examples/kld/syscall/module/syscall.c Thu Jan 7 21:51:07 1999 @@ -0,0 +1,86 @@ +/*- + * Copyright (c) 1999 Assar Westerlund + * 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. + * + * $Id$ + */ + +#include +#include +#include +#include +#include +#include +#include + +/* + * The function for implementing the syscall. + */ + +static int +hello (struct proc *p, void *arg) +{ + printf ("hello kernel\n"); + return 0; +} + +/* + * The `sysent' for the new syscall + */ + +static struct sysent hello_sysent = { + 0, /* sy_narg */ + hello /* sy_call */ +}; + +/* + * The offset in sysent where the syscall is allocated. + */ + +static int offset = NO_SYSCALL; + +/* + * The function called at load/unload. + */ + +static int +load (struct module *module, int cmd, void *arg) +{ + int error = 0; + + switch (cmd) { + case MOD_LOAD : + printf ("syscall loaded at %d\n", offset); + break; + case MOD_UNLOAD : + printf ("syscall unloaded from %d\n", offset); + break; + default : + error = EINVAL; + break; + } + return error; +} + +SYSCALL_MODULE(syscall, &offset, &hello_sysent, load, NULL); --- /dev/null Thu Jan 7 21:47:47 1999 +++ share/examples/kld/syscall/test/call.c Thu Jan 7 21:58:01 1999 @@ -0,0 +1,53 @@ +/*- + * Copyright (c) 1999 Assar Westerlund + * 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. + * + * $Id$ + */ + +#include +#include + +static void usage (void); + +static void +usage (void) +{ + fprintf (stderr, "call syscall-number\n"); + exit (1); +} + +int +main(int argc, char **argv) +{ + char *endptr; + int syscall_num; + + if (argc != 2) + usage (); + syscall_num = strtol (argv[1], &endptr, 0); + if (syscall_num == 0 && argv[1] == endptr) + errx (1, "Bad number `%s'", argv[1]); + return syscall (syscall_num); +} --- /dev/null Thu Jan 7 21:47:47 1999 +++ share/examples/kld/syscall/test/Makefile Thu Jan 7 21:57:42 1999 @@ -0,0 +1,6 @@ +# Makefile for simple caller of syscall + +PROG = call +NOMAN = noman + +.include Index: sys/sys/sysent.h =================================================================== RCS file: /src/fbsd-repository/src/sys/sys/sysent.h,v retrieving revision 1.19 diff -u -w -u -w -r1.19 sysent.h --- sysent.h 1998/09/14 05:36:51 1.19 +++ sysent.h 1999/01/07 20:37:28 @@ -76,6 +76,36 @@ #ifdef KERNEL extern struct sysentvec aout_sysvec; extern struct sysent sysent[]; -#endif + +#define NO_SYSCALL (-1) + +struct module; + +struct syscall_module_data { + int (*chainevh)(struct module *, int, void *); /* next handler */ + void *chainarg; /* arg for next event handler */ + int *offset; /* offset into sysent */ + struct sysent *new_sysent; /* new sysent */ + struct sysent old_sysent; /* old sysent */ +}; + +#define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ +static struct syscall_module_data name##_syscall_mod = { \ + evh, arg, offset, new_sysent \ +}; \ + \ +static moduledata_t name##_mod = { \ + #name, \ + syscall_module_handler, \ + &name##_syscall_mod \ +}; \ +DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE) + +int syscall_register __P((int *offset, struct sysent *new_sysent, + struct sysent *old_sysent)); +int syscall_deregister __P((int *offset, struct sysent *old_sysent)); +int syscall_module_handler __P((struct module *mod, int what, void *arg)); + +#endif /* KERNEL */ #endif /* !_SYS_SYSENT_H_ */ Index: sys/conf/files =================================================================== RCS file: /src/fbsd-repository/src/sys/conf/files,v retrieving revision 1.185 diff -u -w -u -w -r1.185 files --- files 1998/12/28 16:31:26 1.185 +++ files 1999/01/07 19:39:39 @@ -289,6 +289,7 @@ kern/kern_sig.c standard kern/kern_subr.c standard kern/kern_synch.c standard +kern/kern_syscalls.c standard kern/kern_sysctl.c standard kern/kern_time.c standard kern/kern_timeout.c standard --- /dev/null Thu Jan 7 21:47:47 1999 +++ sys/kern/kern_syscalls.c Thu Jan 7 21:37:53 1999 @@ -0,0 +1,94 @@ +/*- + * Copyright (c) 1999 Assar Westerlund + * 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_syscalls.c,v 1.1 1999/01/03 06:00:55 root Exp root $ + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +int +syscall_register(int *offset, struct sysent *new_sysent, + struct sysent *old_sysent) +{ + if (*offset == NO_SYSCALL) { + int i; + + for (i = 1; i < SYS_MAXSYSCALL; ++i) + if (sysent[i].sy_call == (sy_call_t *)lkmnosys) + break; + if (i == SYS_MAXSYSCALL) + return ENFILE; + *offset = i; + } else if (*offset < 0 || *offset >= SYS_MAXSYSCALL) + return EINVAL; + else if (sysent[*offset].sy_call != (sy_call_t *)lkmnosys) + return EEXIST; + + *old_sysent = sysent[*offset]; + sysent[*offset] = *new_sysent; + return 0; +} + +int +syscall_deregister(int *offset, struct sysent *old_sysent) +{ + if (*offset) + sysent[*offset] = *old_sysent; + return 0; +} + +int +syscall_module_handler(struct module *mod, int what, void *arg) +{ + struct syscall_module_data *data = (struct syscall_module_data*)arg; + int error; + + switch (what) { + case MOD_LOAD : + error = syscall_register(data->offset, data->new_sysent, + &data->old_sysent); + if (error) + return error; + break; + case MOD_UNLOAD : + error = syscall_deregister(data->offset, &data->old_sysent); + if (error) + return error; + break; + } + if (data->chainevh) + return data->chainevh(mod, what, data->chainarg); + else + return 0; +} To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message