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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 | /* * linux/fs/stat.c * * Copyright (C) 1991, 1992 Linus Torvalds */ #include <linux/mm.h> #include <linux/errno.h> #include <linux/file.h> #include <linux/smp_lock.h> #include <linux/highuid.h> #include <asm/uaccess.h> /* * Revalidate the inode. This is required for proper NFS attribute caching. */ static __inline__ int do_revalidate(struct dentry *dentry) { struct inode * inode = dentry->d_inode; if (inode->i_op && inode->i_op->revalidate) return inode->i_op->revalidate(dentry); return 0; } #if !defined(__alpha__) && !defined(__sparc__) && !defined(__ia64__) /* * For backward compatibility? Maybe this should be moved * into arch/i386 instead? */ static int cp_old_stat(struct inode * inode, struct __old_kernel_stat * statbuf) { static int warncount = 5; struct __old_kernel_stat tmp; if (warncount) { warncount--; printk("VFS: Warning: %s using old stat() call. Recompile your binary.\n", current->comm); } tmp.st_dev = kdev_t_to_nr(inode->i_dev); tmp.st_ino = inode->i_ino; tmp.st_mode = inode->i_mode; tmp.st_nlink = inode->i_nlink; SET_OLDSTAT_UID(tmp, inode->i_uid); SET_OLDSTAT_GID(tmp, inode->i_gid); tmp.st_rdev = kdev_t_to_nr(inode->i_rdev); tmp.st_size = inode->i_size; tmp.st_atime = inode->i_atime; tmp.st_mtime = inode->i_mtime; tmp.st_ctime = inode->i_ctime; return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; } #endif static int cp_new_stat(struct inode * inode, struct stat * statbuf) { struct stat tmp; unsigned int blocks, indirect; memset(&tmp, 0, sizeof(tmp)); tmp.st_dev = kdev_t_to_nr(inode->i_dev); tmp.st_ino = inode->i_ino; tmp.st_mode = inode->i_mode; tmp.st_nlink = inode->i_nlink; SET_STAT_UID(tmp, inode->i_uid); SET_STAT_GID(tmp, inode->i_gid); tmp.st_rdev = kdev_t_to_nr(inode->i_rdev); tmp.st_size = inode->i_size; tmp.st_atime = inode->i_atime; tmp.st_mtime = inode->i_mtime; tmp.st_ctime = inode->i_ctime; /* * st_blocks and st_blksize are approximated with a simple algorithm if * they aren't supported directly by the filesystem. The minix and msdos * filesystems don't keep track of blocks, so they would either have to * be counted explicitly (by delving into the file itself), or by using * this simple algorithm to get a reasonable (although not 100% accurate) * value. */ /* * Use minix fs values for the number of direct and indirect blocks. The * count is now exact for the minix fs except that it counts zero blocks. * Everything is in units of BLOCK_SIZE until the assignment to * tmp.st_blksize. */ #define D_B 7 #define I_B (BLOCK_SIZE / sizeof(unsigned short)) if (!inode->i_blksize) { blocks = (tmp.st_size + BLOCK_SIZE - 1) / BLOCK_SIZE; if (blocks > D_B) { indirect = (blocks - D_B + I_B - 1) / I_B; blocks += indirect; if (indirect > 1) { indirect = (indirect - 1 + I_B - 1) / I_B; blocks += indirect; if (indirect > 1) blocks++; } } tmp.st_blocks = (BLOCK_SIZE / 512) * blocks; tmp.st_blksize = BLOCK_SIZE; } else { tmp.st_blocks = inode->i_blocks; tmp.st_blksize = inode->i_blksize; } return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; } #if !defined(__alpha__) && !defined(__sparc__) && !defined(__ia64__) /* * For backward compatibility? Maybe this should be moved * into arch/i386 instead? */ asmlinkage long sys_stat(char * filename, struct __old_kernel_stat * statbuf) { struct dentry * dentry; int error; lock_kernel(); dentry = namei(filename); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { error = do_revalidate(dentry); if (!error) error = cp_old_stat(dentry->d_inode, statbuf); dput(dentry); } unlock_kernel(); return error; } #endif asmlinkage long sys_newstat(char * filename, struct stat * statbuf) { struct dentry * dentry; int error; lock_kernel(); dentry = namei(filename); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { error = do_revalidate(dentry); if (!error) error = cp_new_stat(dentry->d_inode, statbuf); dput(dentry); } unlock_kernel(); return error; } #if !defined(__alpha__) && !defined(__sparc__) && !defined(__ia64__) /* * For backward compatibility? Maybe this should be moved * into arch/i386 instead? */ asmlinkage long sys_lstat(char * filename, struct __old_kernel_stat * statbuf) { struct dentry * dentry; int error; lock_kernel(); dentry = lnamei(filename); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { error = do_revalidate(dentry); if (!error) error = cp_old_stat(dentry->d_inode, statbuf); dput(dentry); } unlock_kernel(); return error; } #endif asmlinkage long sys_newlstat(char * filename, struct stat * statbuf) { struct dentry * dentry; int error; lock_kernel(); dentry = lnamei(filename); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { error = do_revalidate(dentry); if (!error) error = cp_new_stat(dentry->d_inode, statbuf); dput(dentry); } unlock_kernel(); return error; } #if !defined(__alpha__) && !defined(__sparc__) && !defined(__ia64__) /* * For backward compatibility? Maybe this should be moved * into arch/i386 instead? */ asmlinkage long sys_fstat(unsigned int fd, struct __old_kernel_stat * statbuf) { struct file * f; int err = -EBADF; lock_kernel(); f = fget(fd); if (f) { struct dentry * dentry = f->f_dentry; err = do_revalidate(dentry); if (!err) err = cp_old_stat(dentry->d_inode, statbuf); fput(f); } unlock_kernel(); return err; } #endif asmlinkage long sys_newfstat(unsigned int fd, struct stat * statbuf) { struct file * f; int err = -EBADF; lock_kernel(); f = fget(fd); if (f) { struct dentry * dentry = f->f_dentry; err = do_revalidate(dentry); if (!err) err = cp_new_stat(dentry->d_inode, statbuf); fput(f); } unlock_kernel(); return err; } asmlinkage long sys_readlink(const char * path, char * buf, int bufsiz) { struct dentry * dentry; int error; if (bufsiz <= 0) return -EINVAL; lock_kernel(); dentry = lnamei(path); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { struct inode * inode = dentry->d_inode; error = -EINVAL; if (inode->i_op && inode->i_op->readlink && !(error = do_revalidate(dentry))) { UPDATE_ATIME(inode); error = inode->i_op->readlink(dentry, buf, bufsiz); } dput(dentry); } unlock_kernel(); return error; } /* ---------- LFS-64 ----------- */ #if !defined(__alpha__) && !defined(__ia64__) static long cp_new_stat64(struct inode * inode, struct stat64 * statbuf) { struct stat64 tmp; unsigned int blocks, indirect; memset(&tmp, 0, sizeof(tmp)); tmp.st_dev = kdev_t_to_nr(inode->i_dev); tmp.st_ino = inode->i_ino; tmp.st_mode = inode->i_mode; tmp.st_nlink = inode->i_nlink; tmp.st_uid = inode->i_uid; tmp.st_gid = inode->i_gid; tmp.st_rdev = kdev_t_to_nr(inode->i_rdev); tmp.st_atime = inode->i_atime; tmp.st_mtime = inode->i_mtime; tmp.st_ctime = inode->i_ctime; tmp.st_size = inode->i_size; /* * st_blocks and st_blksize are approximated with a simple algorithm if * they aren't supported directly by the filesystem. The minix and msdos * filesystems don't keep track of blocks, so they would either have to * be counted explicitly (by delving into the file itself), or by using * this simple algorithm to get a reasonable (although not 100% accurate) * value. */ /* * Use minix fs values for the number of direct and indirect blocks. The * count is now exact for the minix fs except that it counts zero blocks. * Everything is in units of BLOCK_SIZE until the assignment to * tmp.st_blksize. */ #define D_B 7 #define I_B (BLOCK_SIZE / sizeof(unsigned short)) if (!inode->i_blksize) { blocks = (tmp.st_size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; if (blocks > D_B) { indirect = (blocks - D_B + I_B - 1) / I_B; blocks += indirect; if (indirect > 1) { indirect = (indirect - 1 + I_B - 1) / I_B; blocks += indirect; if (indirect > 1) blocks++; } } tmp.st_blocks = (BLOCK_SIZE / 512) * blocks; tmp.st_blksize = BLOCK_SIZE; } else { tmp.st_blocks = inode->i_blocks; tmp.st_blksize = inode->i_blksize; } return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0; } asmlinkage long sys_stat64(char * filename, struct stat64 * statbuf, long flags) { struct dentry * dentry; int error; lock_kernel(); dentry = namei(filename); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { error = do_revalidate(dentry); if (!error) error = cp_new_stat64(dentry->d_inode, statbuf); dput(dentry); } unlock_kernel(); return error; } asmlinkage long sys_lstat64(char * filename, struct stat64 * statbuf, long flags) { struct dentry * dentry; int error; lock_kernel(); dentry = lnamei(filename); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { error = do_revalidate(dentry); if (!error) error = cp_new_stat64(dentry->d_inode, statbuf); dput(dentry); } unlock_kernel(); return error; } asmlinkage long sys_fstat64(unsigned long fd, struct stat64 * statbuf, long flags) { struct file * f; int err = -EBADF; lock_kernel(); f = fget(fd); if (f) { struct dentry * dentry = f->f_dentry; err = do_revalidate(dentry); if (!err) err = cp_new_stat64(dentry->d_inode, statbuf); fput(f); } unlock_kernel(); return err; } #endif /* LFS-64 */ |