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linux_llseek.c revision 1.3
      1 /*	$NetBSD: linux_llseek.c,v 1.3 1995/04/04 04:21:30 mycroft Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1995 Frank van der Linden
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *      This product includes software developed for the NetBSD Project
     18  *      by Frank van der Linden
     19  * 4. The name of the author may not be used to endorse or promote products
     20  *    derived from this software without specific prior written permission
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     32  */
     33 
     34 #include <sys/param.h>
     35 #include <sys/systm.h>
     36 #include <sys/namei.h>
     37 #include <sys/proc.h>
     38 #include <sys/file.h>
     39 #include <sys/stat.h>
     40 #include <sys/filedesc.h>
     41 #include <sys/ioctl.h>
     42 #include <sys/kernel.h>
     43 #include <sys/mount.h>
     44 #include <sys/malloc.h>
     45 
     46 #include <sys/syscallargs.h>
     47 
     48 #include <compat/linux/linux_types.h>
     49 #include <compat/linux/linux_syscallargs.h>
     50 #include <compat/linux/linux_fcntl.h>
     51 #include <compat/linux/linux_util.h>
     52 
     53 /*
     54  * Some file-related calls are handled here. The usual flag conversion
     55  * an structure conversion is done, and alternate emul path searching.
     56  */
     57 
     58 /*
     59  * The next two functions convert between the Linux and NetBSD values
     60  * of the flags used in open(2) and fcntl(2).
     61  */
     62 static int
     63 linux_to_bsd_ioflags(int lflags)
     64 {
     65 	int res = 0;
     66 
     67 	res |= cvtto_bsd_mask(lflags, LINUX_O_WRONLY, O_WRONLY);
     68 	res |= cvtto_bsd_mask(lflags, LINUX_O_RDONLY, O_RDONLY);
     69 	res |= cvtto_bsd_mask(lflags, LINUX_O_RDWR, O_RDWR);
     70 	res |= cvtto_bsd_mask(lflags, LINUX_O_CREAT, O_CREAT);
     71 	res |= cvtto_bsd_mask(lflags, LINUX_O_EXCL, O_EXCL);
     72 	res |= cvtto_bsd_mask(lflags, LINUX_O_NOCTTY, O_NOCTTY);
     73 	res |= cvtto_bsd_mask(lflags, LINUX_O_TRUNC, O_TRUNC);
     74 	res |= cvtto_bsd_mask(lflags, LINUX_O_NDELAY, O_NDELAY);
     75 	res |= cvtto_bsd_mask(lflags, LINUX_O_SYNC, O_FSYNC);
     76 	res |= cvtto_bsd_mask(lflags, LINUX_FASYNC, O_ASYNC);
     77 	res |= cvtto_bsd_mask(lflags, LINUX_O_APPEND, O_APPEND);
     78 
     79 	return res;
     80 }
     81 
     82 static int
     83 bsd_to_linux_ioflags(int bflags)
     84 {
     85 	int res = 0;
     86 
     87 	res |= cvtto_linux_mask(bflags, O_WRONLY, LINUX_O_WRONLY);
     88 	res |= cvtto_linux_mask(bflags, O_RDONLY, LINUX_O_RDONLY);
     89 	res |= cvtto_linux_mask(bflags, O_RDWR, LINUX_O_RDWR);
     90 	res |= cvtto_linux_mask(bflags, O_CREAT, LINUX_O_CREAT);
     91 	res |= cvtto_linux_mask(bflags, O_EXCL, LINUX_O_EXCL);
     92 	res |= cvtto_linux_mask(bflags, O_NOCTTY, LINUX_O_NOCTTY);
     93 	res |= cvtto_linux_mask(bflags, O_TRUNC, LINUX_O_TRUNC);
     94 	res |= cvtto_linux_mask(bflags, O_NDELAY, LINUX_O_NDELAY);
     95 	res |= cvtto_linux_mask(bflags, O_FSYNC, LINUX_O_SYNC);
     96 	res |= cvtto_linux_mask(bflags, O_ASYNC, LINUX_FASYNC);
     97 	res |= cvtto_linux_mask(bflags, O_APPEND, LINUX_O_APPEND);
     98 
     99 	return res;
    100 }
    101 
    102 /*
    103  * creat(2) is an obsolete function, but it's present as a Linux
    104  * system call, so let's deal with it.
    105  *
    106  * Just call open(2) with the TRUNC, CREAT and WRONLY flags.
    107  */
    108 int
    109 linux_creat(p, uap, retval)
    110 	struct proc *p;
    111 	struct linux_creat_args /* {
    112 		syscallarg(char *) path;
    113 		syscallarg(int) mode;
    114 	} */ *uap;
    115 	register_t *retval;
    116 {
    117 	struct open_args oa;
    118 	caddr_t sg;
    119 
    120 	sg = stackgap_init();
    121 	CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
    122 
    123 	SCARG(&oa, path) = SCARG(uap, path);
    124 	SCARG(&oa, flags) = O_CREAT | O_TRUNC | O_WRONLY;
    125 	SCARG(&oa, mode) = SCARG(uap, mode);
    126 	return open(p, &oa, retval);
    127 }
    128 
    129 /*
    130  * open(2). Take care of the different flag values, and let the
    131  * NetBSD syscall do the real work. See if this operation
    132  * gives the current process a controlling terminal.
    133  * (XXX is this necessary?)
    134  */
    135 int
    136 linux_open(p, uap, retval)
    137 	struct proc *p;
    138 	struct linux_open_args /* {
    139 		syscallarg(char *) path;
    140 		syscallarg(int) flags;
    141 		syscallarg(int) mode;
    142 	} */ *uap;
    143 	register_t *retval;
    144 {
    145 	int error, fl;
    146 	struct open_args boa;
    147 	caddr_t sg;
    148 
    149 	sg = stackgap_init();
    150 
    151 	fl = linux_to_bsd_ioflags(SCARG(uap, flags));
    152 
    153 	if (fl & O_CREAT)
    154 		CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
    155 	else
    156 		CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    157 
    158 	SCARG(&boa, path) = SCARG(uap, path);
    159 	SCARG(&boa, flags) = fl;
    160 	SCARG(&boa, mode) = SCARG(uap, mode);
    161 
    162 	if ((error = open(p, &boa, retval)))
    163 		return error;
    164 
    165 	/*
    166 	 * this bit from sunos_misc.c (and svr4_fcntl.c).
    167 	 * If we are a session leader, and we don't have a controlling
    168 	 * terminal yet, and the O_NOCTTY flag is not set, try to make
    169 	 * this the controlling terminal.
    170 	 */
    171         if (!(fl & O_NOCTTY) && SESS_LEADER(p) && !(p->p_flag & P_CONTROLT)) {
    172                 struct filedesc *fdp = p->p_fd;
    173                 struct file     *fp = fdp->fd_ofiles[*retval];
    174 
    175                 /* ignore any error, just give it a try */
    176                 if (fp->f_type == DTYPE_VNODE)
    177                         (fp->f_ops->fo_ioctl) (fp, TIOCSCTTY, (caddr_t) 0, p);
    178         }
    179 	return 0;
    180 }
    181 
    182 /*
    183  * This appears to be part of a Linux attempt to switch to 64 bits file sizes.
    184  */
    185 int
    186 linux_llseek(p, uap, retval)
    187 	struct proc *p;
    188 	struct linux_llseek_args /* {
    189 		syscallarg(int) fd;
    190 		syscallarg(uint32_t) ohigh;
    191 		syscallarg(uint32_t) olow;
    192 		syscallarg(caddr_t) res;
    193 		syscallarg(int) whence;
    194 	} */ *uap;
    195 	register_t *retval;
    196 {
    197 	struct lseek_args bla;
    198 	int error;
    199 	off_t off;
    200 
    201 	off = SCARG(uap, olow) | (((off_t) SCARG(uap, ohigh)) << 32);
    202 
    203 	SCARG(&bla, fd) = SCARG(uap, fd);
    204 	SCARG(&bla, offset) = off;
    205 	SCARG(&bla, whence) = SCARG(uap, whence);
    206 
    207 	if ((error = lseek(p, &bla, retval)))
    208 		return error;
    209 
    210 	if ((error = copyout(retval, SCARG(uap, res), sizeof (off_t))))
    211 		return error;
    212 
    213 	retval[0] = 0;
    214 	return 0;
    215 }
    216 
    217 /*
    218  * The next two functions take care of converting the flock
    219  * structure back and forth between Linux and NetBSD format.
    220  * The only difference in the structures is the order of
    221  * the fields, and the 'whence' value.
    222  */
    223 static void
    224 bsd_to_linux_flock(bfp, lfp)
    225 	struct flock *bfp;
    226 	struct linux_flock *lfp;
    227 {
    228 	lfp->l_start = bfp->l_start;
    229 	lfp->l_len = bfp->l_len;
    230 	lfp->l_pid = bfp->l_pid;
    231 	lfp->l_whence = bfp->l_whence;
    232 	switch (bfp->l_type) {
    233 	case F_RDLCK:
    234 		lfp->l_type = LINUX_F_RDLCK;
    235 		break;
    236 	case F_UNLCK:
    237 		lfp->l_type = LINUX_F_UNLCK;
    238 		break;
    239 	case F_WRLCK:
    240 		lfp->l_type = LINUX_F_WRLCK;
    241 		break;
    242 	}
    243 }
    244 
    245 static void
    246 linux_to_bsd_flock(lfp, bfp)
    247 	struct linux_flock *lfp;
    248 	struct flock *bfp;
    249 {
    250 	bfp->l_start = lfp->l_start;
    251 	bfp->l_len = lfp->l_len;
    252 	bfp->l_pid = lfp->l_pid;
    253 	bfp->l_whence = lfp->l_whence;
    254 	switch (lfp->l_type) {
    255 	case LINUX_F_RDLCK:
    256 		bfp->l_type = F_RDLCK;
    257 		break;
    258 	case LINUX_F_UNLCK:
    259 		bfp->l_type = F_UNLCK;
    260 		break;
    261 	case LINUX_F_WRLCK:
    262 		bfp->l_type = F_WRLCK;
    263 		break;
    264 	}
    265 }
    266 
    267 /*
    268  * Most actions in the fcntl() call are straightforward; simply
    269  * pass control to the NetBSD system call. A few commands need
    270  * conversions after the actual system call has done its work,
    271  * because the flag values and lock structure are different.
    272  */
    273 int
    274 linux_fcntl(p, uap, retval)
    275 	struct proc *p;
    276 	struct linux_fcntl_args /* {
    277 		syscallarg(int) fd;
    278 		syscallarg(int) cmd;
    279 		syscallarg(void *) arg;
    280 	} */ *uap;
    281 	register_t *retval;
    282 {
    283 	int fd, cmd, error, *tval,val;
    284 	caddr_t arg, sg;
    285 	struct linux_flock lfl;
    286 	struct flock *bfp, bfl;
    287 	struct fcntl_args fca;
    288 
    289 	fd = SCARG(uap, fd);
    290 	cmd = SCARG(uap, cmd);
    291 	arg = (caddr_t) SCARG(uap, arg);
    292 
    293 	switch (cmd) {
    294 	case LINUX_F_DUPFD:
    295 		cmd = F_DUPFD;
    296 		break;
    297 	case LINUX_F_GETFD:
    298 		cmd = F_GETFD;
    299 		break;
    300 	case LINUX_F_SETFD:
    301 		cmd = F_SETFD;
    302 		break;
    303 	case LINUX_F_GETFL:
    304 		SCARG(&fca, fd) = fd;
    305 		SCARG(&fca, cmd) = F_GETFL;
    306 		SCARG(&fca, arg) = arg;
    307 		if ((error = fcntl(p, &fca, retval)))
    308 			return error;
    309 		retval[0] = bsd_to_linux_ioflags(retval[0]);
    310 		return 0;
    311 	case LINUX_F_SETFL:
    312 		if ((error = copyin(SCARG(uap, arg), &val, sizeof (int))))
    313 			return error;
    314 		val = linux_to_bsd_ioflags(val);
    315 		sg = stackgap_init();
    316 		tval = (int *) stackgap_alloc(&sg, sizeof (int));
    317 		if ((error = copyout(&val, tval, sizeof (int))))
    318 			return error;
    319 		SCARG(&fca, fd) = fd;
    320 		SCARG(&fca, cmd) = F_SETFL;
    321 		SCARG(&fca, arg) = tval;
    322 		return fcntl(p, &fca, retval);
    323 	case LINUX_F_GETLK:
    324 		sg = stackgap_init();
    325 		bfp = (struct flock *) stackgap_alloc(&sg, sizeof *bfp);
    326 		SCARG(&fca, fd) = fd;
    327 		SCARG(&fca, cmd) = F_GETLK;
    328 		SCARG(&fca, arg) = bfp;
    329 		if ((error = fcntl(p, &fca, retval)))
    330 			return error;
    331 		if ((error = copyin(bfp, &bfl, sizeof bfl)))
    332 			return error;
    333 		bsd_to_linux_flock(&bfl, &lfl);
    334 		return copyout(&lfl, arg, sizeof lfl);
    335 		break;
    336 	case LINUX_F_SETLK:
    337 	case LINUX_F_SETLKW:
    338 		cmd = (cmd == LINUX_F_SETLK ? F_SETLK : F_SETLKW);
    339 		if ((error = copyin(arg, &lfl, sizeof lfl)))
    340 			return error;
    341 		linux_to_bsd_flock(&lfl, &bfl);
    342 		sg = stackgap_init();
    343 		bfp = (struct flock *) stackgap_alloc(&sg, sizeof *bfp);
    344 		if ((error = copyout(&bfl, bfp, sizeof bfl)))
    345 			return error;
    346 		SCARG(&fca, fd) = fd;
    347 		SCARG(&fca, cmd) = cmd;
    348 		SCARG(&fca, arg) = bfp;
    349 		return fcntl(p, &fca, retval);
    350 		break;
    351 	case LINUX_F_SETOWN:
    352 		cmd = F_SETOWN;
    353 		break;
    354 	case LINUX_F_GETOWN:
    355 		cmd = F_GETOWN;
    356 		break;
    357 	default:
    358 		return EOPNOTSUPP;
    359 	}
    360 
    361 	SCARG(&fca, fd) = fd;
    362 	SCARG(&fca, cmd) = cmd;
    363 	SCARG(&fca, arg) = arg;
    364 	return fcntl(p, uap, retval);
    365 }
    366 
    367 /*
    368  * Convert a NetBSD stat structure to a Linux stat structure.
    369  * Only the order of the fields and the padding in the structure
    370  * is different.
    371  */
    372 static void
    373 bsd_to_linux_stat(bsp, lsp)
    374 	struct stat *bsp;
    375 	struct linux_stat *lsp;
    376 {
    377 	lsp->lst_dev     = bsp->st_dev;
    378 	lsp->lst_ino     = bsp->st_ino;
    379 	lsp->lst_mode    = bsp->st_mode;
    380 	lsp->lst_nlink   = bsp->st_nlink;
    381 	lsp->lst_uid     = bsp->st_uid;
    382 	lsp->lst_gid     = bsp->st_gid;
    383 	lsp->lst_rdev    = bsp->st_rdev;
    384 	lsp->lst_size    = bsp->st_size;
    385 	lsp->lst_blksize = bsp->st_blksize;
    386 	lsp->lst_blocks  = bsp->st_blocks;
    387 	lsp->lst_atime   = bsp->st_atime;
    388 	lsp->lst_mtime   = bsp->st_mtime;
    389 	lsp->lst_ctime   = bsp->st_ctime;
    390 }
    391 
    392 /*
    393  * The stat functions below are plain sailing. stat and lstat are handled
    394  * by one function to avoid code duplication.
    395  */
    396 int
    397 linux_fstat(p, uap, retval)
    398 	struct proc *p;
    399 	struct linux_fstat_args /* {
    400 		syscallarg(int) fd;
    401 		syscallarg(linux_stat *) sp;
    402 	} */ *uap;
    403 	register_t *retval;
    404 {
    405 	struct fstat_args fsa;
    406 	struct linux_stat tmplst;
    407 	struct stat *st,tmpst;
    408 	caddr_t sg;
    409 	int error;
    410 
    411 	sg = stackgap_init();
    412 
    413 	st = stackgap_alloc(&sg, sizeof (struct stat));
    414 
    415 	SCARG(&fsa, fd) = SCARG(uap, fd);
    416 	SCARG(&fsa, sb) = st;
    417 
    418 	if ((error = fstat(p, &fsa, retval)))
    419 		return error;
    420 
    421 	if ((error = copyin(st, &tmpst, sizeof tmpst)))
    422 		return error;
    423 
    424 	bsd_to_linux_stat(&tmpst, &tmplst);
    425 
    426 	if ((error = copyout(&tmplst, SCARG(uap, sp), sizeof tmplst)))
    427 		return error;
    428 
    429 	return 0;
    430 }
    431 
    432 static int
    433 linux_stat1(p, uap, retval, dolstat)
    434 	struct proc *p;
    435 	struct linux_stat_args *uap;
    436 	register_t *retval;
    437 	int dolstat;
    438 {
    439 	struct stat_args sa;
    440 	struct linux_stat tmplst;
    441 	struct stat *st, tmpst;
    442 	caddr_t sg;
    443 	int error;
    444 
    445 	sg = stackgap_init();
    446 
    447 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    448 
    449 	st = stackgap_alloc(&sg, sizeof (struct stat));
    450 	SCARG(&sa, ub) = st;
    451 	SCARG(&sa, path) = SCARG(uap, path);
    452 
    453 	if ((error = (dolstat ? lstat(p, &sa, retval) : stat(p, &sa, retval))))
    454 		return error;
    455 
    456 	if ((error = copyin(st, &tmpst, sizeof tmpst)))
    457 		return error;
    458 
    459 	bsd_to_linux_stat(&tmpst, &tmplst);
    460 
    461 	if ((error = copyout(&tmplst, SCARG(uap, sp), sizeof tmplst)))
    462 		return error;
    463 
    464 	return 0;
    465 }
    466 
    467 int
    468 linux_stat(p, uap, retval)
    469 	struct proc *p;
    470 	struct linux_stat_args /* {
    471 		syscallarg(char *) path;
    472 		syscallarg(struct linux_stat *) sp;
    473 	} */ *uap;
    474 	register_t *retval;
    475 {
    476 	return linux_stat1(p, uap, retval, 0);
    477 }
    478 
    479 int
    480 linux_lstat(p, uap, retval)
    481 	struct proc *p;
    482 	struct linux_lstat_args /* {
    483 		syscallarg(char *) path;
    484 		syscallarg(struct linux_stat *) sp;
    485 	} */ *uap;
    486 	register_t *retval;
    487 {
    488 	return linux_stat1(p, uap, retval, 1);
    489 }
    490 
    491 /*
    492  * The following syscalls are only here because of the alternate path check.
    493  */
    494 int
    495 linux_access(p, uap, retval)
    496 	struct proc *p;
    497 	struct linux_access_args /* {
    498 		syscallarg(char *) path;
    499 		syscallarg(int) flags;
    500 	} */ *uap;
    501 	register_t *retval;
    502 {
    503 	caddr_t sg = stackgap_init();
    504 
    505 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    506 
    507 	return access(p, uap, retval);
    508 }
    509 
    510 int
    511 linux_unlink(p, uap, retval)
    512 	struct proc *p;
    513 	struct linux_unlink_args /* {
    514 		syscallarg(char *) path;
    515 	} */ *uap;
    516 	register_t *retval;
    517 
    518 {
    519 	caddr_t sg = stackgap_init();
    520 
    521 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    522 
    523 	return unlink(p, uap, retval);
    524 }
    525 
    526 int linux_chdir(p, uap, retval)
    527 	struct proc *p;
    528 	struct linux_chdir_args /* {
    529 		syscallarg(char *) path;
    530 	} */ *uap;
    531 	register_t *retval;
    532 {
    533 	caddr_t sg = stackgap_init();
    534 
    535 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    536 
    537 	return chdir(p, uap, retval);
    538 }
    539 
    540 int
    541 linux_mknod(p, uap, retval)
    542 	struct proc *p;
    543 	struct linux_mknod_args /* {
    544 		syscallarg(char *) path;
    545 		syscallarg(int) mode;
    546 		syscallarg(int) dev;
    547 	} */ *uap;
    548 	register_t *retval;
    549 {
    550 	caddr_t sg = stackgap_init();
    551 
    552 	CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
    553 
    554 	return mknod(p, uap, retval);
    555 }
    556 
    557 int
    558 linux_chmod(p, uap, retval)
    559 	struct proc *p;
    560 	struct linux_chmod_args /* {
    561 		syscallarg(char *) path;
    562 		syscallarg(int) mode;
    563 	} */ *uap;
    564 	register_t *retval;
    565 {
    566 	caddr_t sg = stackgap_init();
    567 
    568 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    569 
    570 	return chmod(p, uap, retval);
    571 }
    572 
    573 int
    574 linux_chown(p, uap, retval)
    575 	struct proc *p;
    576 	struct linux_chown_args /* {
    577 		syscallarg(char *) path;
    578 		syscallarg(int) uid;
    579 		syscallarg(int) gid;
    580 	} */ *uap;
    581 	register_t *retval;
    582 {
    583 	caddr_t sg = stackgap_init();
    584 
    585 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    586 
    587 	return chmod(p, uap, retval);
    588 }
    589 
    590 int
    591 linux_rename(p, uap, retval)
    592 	struct proc *p;
    593 	struct linux_rename_args /* {
    594 		syscallarg(char *) from;
    595 		syscallarg(char *) to;
    596 	} */ *uap;
    597 	register_t *retval;
    598 {
    599 	caddr_t sg = stackgap_init();
    600 
    601 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, from));
    602 	CHECK_ALT_CREAT(p, &sg, SCARG(uap, to));
    603 
    604 	return rename(p, uap, retval);
    605 }
    606 
    607 int
    608 linux_mkdir(p, uap, retval)
    609 	struct proc *p;
    610 	struct linux_mkdir_args /* {
    611 		syscallarg(char *) path;
    612 	} */ *uap;
    613 	register_t *retval;
    614 {
    615 	caddr_t sg = stackgap_init();
    616 
    617 	CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
    618 	return mkdir(p, uap, retval);
    619 }
    620 
    621 int
    622 linux_rmdir(p, uap, retval)
    623 	struct proc *p;
    624 	struct linux_rmdir_args /* {
    625 		syscallarg(char *) path;
    626 	} */ *uap;
    627 	register_t *retval;
    628 {
    629 	caddr_t sg = stackgap_init();
    630 
    631 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    632 	return rmdir(p, uap, retval);
    633 }
    634 
    635 int
    636 linux_symlink(p, uap, retval)
    637 	struct proc *p;
    638 	struct linux_symlink_args /* {
    639 		syscallarg(char *) path;
    640 		syscallarg(char *) to;
    641 	} */ *uap;
    642 	register_t *retval;
    643 {
    644 	caddr_t sg = stackgap_init();
    645 
    646 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    647 	CHECK_ALT_CREAT(p, &sg, SCARG(uap, to));
    648 
    649 	return symlink(p, uap, retval);
    650 }
    651 
    652 int
    653 linux_readlink(p, uap, retval)
    654 	struct proc *p;
    655 	struct linux_readlink_args /* {
    656 		syscallarg(char *) name;
    657 		syscallarg(char *) buf;
    658 		syscallarg(int) count;
    659 	} */ *uap;
    660 {
    661 	caddr_t sg = stackgap_init();
    662 
    663 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, name));
    664 	return readlink(p, uap, retval);
    665 }
    666 
    667 int
    668 linux_truncate(p, uap, retval)
    669 	struct proc *p;
    670 	struct linux_truncate_args /* {
    671 		syscallarg(char *) path;
    672 		syscallarg(long) length;
    673 	} */ *uap;
    674 {
    675 	caddr_t sg = stackgap_init();
    676 
    677 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
    678 	return compat_43_truncate(p, uap, retval);
    679 }
    680