1 /* $NetBSD: linux_file64.c,v 1.51 2010/06/24 13:03:07 hannken Exp $ */ 2 3 /*- 4 * Copyright (c) 1995, 1998, 2000, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Frank van der Linden and Eric Haszlakiewicz. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Linux 64bit filesystem calls. Used on 32bit archs, not used on 64bit ones. 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: linux_file64.c,v 1.51 2010/06/24 13:03:07 hannken Exp $"); 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/namei.h> 42 #include <sys/proc.h> 43 #include <sys/dirent.h> 44 #include <sys/file.h> 45 #include <sys/stat.h> 46 #include <sys/filedesc.h> 47 #include <sys/ioctl.h> 48 #include <sys/kernel.h> 49 #include <sys/mount.h> 50 #include <sys/malloc.h> 51 #include <sys/namei.h> 52 #include <sys/vfs_syscalls.h> 53 #include <sys/vnode.h> 54 #include <sys/tty.h> 55 #include <sys/conf.h> 56 57 #include <sys/syscallargs.h> 58 59 #include <compat/linux/common/linux_types.h> 60 #include <compat/linux/common/linux_signal.h> 61 #include <compat/linux/common/linux_fcntl.h> 62 #include <compat/linux/common/linux_util.h> 63 #include <compat/linux/common/linux_machdep.h> 64 #include <compat/linux/common/linux_dirent.h> 65 #include <compat/linux/common/linux_ipc.h> 66 #include <compat/linux/common/linux_sem.h> 67 68 #include <compat/linux/linux_syscallargs.h> 69 70 #ifndef alpha 71 72 static void bsd_to_linux_stat(struct stat *, struct linux_stat64 *); 73 74 /* 75 * Convert a NetBSD stat structure to a Linux stat structure. 76 * Only the order of the fields and the padding in the structure 77 * is different. linux_fakedev is a machine-dependent function 78 * which optionally converts device driver major/minor numbers 79 * (XXX horrible, but what can you do against code that compares 80 * things against constant major device numbers? sigh) 81 */ 82 static void 83 bsd_to_linux_stat(struct stat *bsp, struct linux_stat64 *lsp) 84 { 85 lsp->lst_dev = linux_fakedev(bsp->st_dev, 0); 86 lsp->lst_ino = bsp->st_ino; 87 lsp->lst_mode = (linux_mode_t)bsp->st_mode; 88 if (bsp->st_nlink >= (1 << 15)) 89 lsp->lst_nlink = (1 << 15) - 1; 90 else 91 lsp->lst_nlink = (linux_nlink_t)bsp->st_nlink; 92 lsp->lst_uid = bsp->st_uid; 93 lsp->lst_gid = bsp->st_gid; 94 lsp->lst_rdev = linux_fakedev(bsp->st_rdev, 1); 95 lsp->lst_size = bsp->st_size; 96 lsp->lst_blksize = bsp->st_blksize; 97 lsp->lst_blocks = bsp->st_blocks; 98 lsp->lst_atime = bsp->st_atime; 99 lsp->lst_mtime = bsp->st_mtime; 100 lsp->lst_ctime = bsp->st_ctime; 101 # ifdef LINUX_STAT64_HAS_NSEC 102 lsp->lst_atime_nsec = bsp->st_atimensec; 103 lsp->lst_mtime_nsec = bsp->st_mtimensec; 104 lsp->lst_ctime_nsec = bsp->st_ctimensec; 105 # endif 106 # if LINUX_STAT64_HAS_BROKEN_ST_INO 107 lsp->__lst_ino = (linux_ino_t) bsp->st_ino; 108 # endif 109 } 110 111 /* 112 * The stat functions below are plain sailing. stat and lstat are handled 113 * by one function to avoid code duplication. 114 */ 115 int 116 linux_sys_fstat64(struct lwp *l, const struct linux_sys_fstat64_args *uap, register_t *retval) 117 { 118 /* { 119 syscallarg(int) fd; 120 syscallarg(struct linux_stat64 *) sp; 121 } */ 122 struct linux_stat64 tmplst; 123 struct stat tmpst; 124 int error; 125 126 error = do_sys_fstat(SCARG(uap, fd), &tmpst); 127 if (error != 0) 128 return error; 129 130 bsd_to_linux_stat(&tmpst, &tmplst); 131 132 return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst); 133 } 134 135 static int 136 linux_do_stat64(struct lwp *l, const struct linux_sys_stat64_args *uap, register_t *retval, int flags) 137 { 138 struct linux_stat64 tmplst; 139 struct stat tmpst; 140 int error; 141 142 error = do_sys_stat(SCARG(uap, path), flags, &tmpst); 143 if (error != 0) 144 return error; 145 146 bsd_to_linux_stat(&tmpst, &tmplst); 147 148 return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst); 149 } 150 151 int 152 linux_sys_stat64(struct lwp *l, const struct linux_sys_stat64_args *uap, register_t *retval) 153 { 154 /* { 155 syscallarg(const char *) path; 156 syscallarg(struct linux_stat64 *) sp; 157 } */ 158 159 return linux_do_stat64(l, uap, retval, FOLLOW); 160 } 161 162 int 163 linux_sys_lstat64(struct lwp *l, const struct linux_sys_lstat64_args *uap, register_t *retval) 164 { 165 /* { 166 syscallarg(const char *) path; 167 syscallarg(struct linux_stat64 *) sp; 168 } */ 169 170 return linux_do_stat64(l, (const void *)uap, retval, NOFOLLOW); 171 } 172 173 int 174 linux_sys_truncate64(struct lwp *l, const struct linux_sys_truncate64_args *uap, register_t *retval) 175 { 176 /* { 177 syscallarg(const char *) path; 178 syscallarg(off_t) length; 179 } */ 180 struct sys_truncate_args ta; 181 182 /* Linux doesn't have the 'pad' pseudo-parameter */ 183 SCARG(&ta, path) = SCARG(uap, path); 184 SCARG(&ta, PAD) = 0; 185 SCARG(&ta, length) = SCARG(uap, length); 186 187 return sys_truncate(l, &ta, retval); 188 } 189 190 int 191 linux_sys_ftruncate64(struct lwp *l, const struct linux_sys_ftruncate64_args *uap, register_t *retval) 192 { 193 /* { 194 syscallarg(unsigned int) fd; 195 syscallarg(off_t) length; 196 } */ 197 struct sys_ftruncate_args ta; 198 199 /* Linux doesn't have the 'pad' pseudo-parameter */ 200 SCARG(&ta, fd) = SCARG(uap, fd); 201 SCARG(&ta, PAD) = 0; 202 SCARG(&ta, length) = SCARG(uap, length); 203 204 return sys_ftruncate(l, &ta, retval); 205 } 206 #endif /* !alpha */ 207 208 /* 209 * Linux 'readdir' call. This code is mostly taken from the 210 * SunOS getdents call (see compat/sunos/sunos_misc.c), though 211 * an attempt has been made to keep it a little cleaner. 212 * 213 * The d_off field contains the offset of the next valid entry, 214 * unless the older Linux getdents(2), which used to have it set 215 * to the offset of the entry itself. This function also doesn't 216 * need to deal with the old count == 1 glibc problem. 217 * 218 * Read in BSD-style entries, convert them, and copy them out. 219 * 220 * Note that this doesn't handle union-mounted filesystems. 221 */ 222 int 223 linux_sys_getdents64(struct lwp *l, const struct linux_sys_getdents64_args *uap, register_t *retval) 224 { 225 /* { 226 syscallarg(int) fd; 227 syscallarg(struct linux_dirent64 *) dent; 228 syscallarg(unsigned int) count; 229 } */ 230 struct dirent *bdp; 231 struct vnode *vp; 232 char *inp, *tbuf; /* BSD-format */ 233 int len, reclen; /* BSD-format */ 234 char *outp; /* Linux-format */ 235 int resid, linux_reclen = 0; /* Linux-format */ 236 file_t *fp; 237 struct uio auio; 238 struct iovec aiov; 239 struct linux_dirent64 idb; 240 off_t off; /* true file offset */ 241 int buflen, error, eofflag, nbytes; 242 struct vattr va; 243 off_t *cookiebuf = NULL, *cookie; 244 int ncookies; 245 246 /* fd_getvnode() will use the descriptor for us */ 247 if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0) 248 return (error); 249 250 if ((fp->f_flag & FREAD) == 0) { 251 error = EBADF; 252 goto out1; 253 } 254 255 vp = (struct vnode *)fp->f_data; 256 if (vp->v_type != VDIR) { 257 error = EINVAL; 258 goto out1; 259 } 260 261 if ((error = VOP_GETATTR(vp, &va, l->l_cred))) 262 goto out1; 263 264 nbytes = SCARG(uap, count); 265 buflen = min(MAXBSIZE, nbytes); 266 if (buflen < va.va_blocksize) 267 buflen = va.va_blocksize; 268 tbuf = malloc(buflen, M_TEMP, M_WAITOK); 269 270 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 271 off = fp->f_offset; 272 again: 273 aiov.iov_base = tbuf; 274 aiov.iov_len = buflen; 275 auio.uio_iov = &aiov; 276 auio.uio_iovcnt = 1; 277 auio.uio_rw = UIO_READ; 278 auio.uio_resid = buflen; 279 auio.uio_offset = off; 280 UIO_SETUP_SYSSPACE(&auio); 281 /* 282 * First we read into the malloc'ed buffer, then 283 * we massage it into user space, one record at a time. 284 */ 285 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf, 286 &ncookies); 287 if (error) 288 goto out; 289 290 inp = tbuf; 291 outp = (void *)SCARG(uap, dent); 292 resid = nbytes; 293 if ((len = buflen - auio.uio_resid) == 0) 294 goto eof; 295 296 for (cookie = cookiebuf; len > 0; len -= reclen) { 297 bdp = (struct dirent *)inp; 298 reclen = bdp->d_reclen; 299 if (reclen & 3) 300 panic("linux_readdir"); 301 if (bdp->d_fileno == 0) { 302 inp += reclen; /* it is a hole; squish it out */ 303 if (cookie) 304 off = *cookie++; 305 else 306 off += reclen; 307 continue; 308 } 309 linux_reclen = LINUX_RECLEN(&idb, bdp->d_namlen); 310 if (reclen > len || resid < linux_reclen) { 311 /* entry too big for buffer, so just stop */ 312 outp++; 313 break; 314 } 315 if (cookie) 316 off = *cookie++; /* each entry points to next */ 317 else 318 off += reclen; 319 /* 320 * Massage in place to make a Linux-shaped dirent (otherwise 321 * we have to worry about touching user memory outside of 322 * the copyout() call). 323 */ 324 idb.d_ino = bdp->d_fileno; 325 idb.d_type = bdp->d_type; 326 idb.d_off = off; 327 idb.d_reclen = (u_short)linux_reclen; 328 strcpy(idb.d_name, bdp->d_name); 329 if ((error = copyout((void *)&idb, outp, linux_reclen))) 330 goto out; 331 /* advance past this real entry */ 332 inp += reclen; 333 /* advance output past Linux-shaped entry */ 334 outp += linux_reclen; 335 resid -= linux_reclen; 336 } 337 338 /* if we squished out the whole block, try again */ 339 if (outp == (void *)SCARG(uap, dent)) { 340 if (cookiebuf) 341 free(cookiebuf, M_TEMP); 342 cookiebuf = NULL; 343 goto again; 344 } 345 fp->f_offset = off; /* update the vnode offset */ 346 347 eof: 348 *retval = nbytes - resid; 349 out: 350 VOP_UNLOCK(vp); 351 if (cookiebuf) 352 free(cookiebuf, M_TEMP); 353 free(tbuf, M_TEMP); 354 out1: 355 fd_putfile(SCARG(uap, fd)); 356 return error; 357 } 358