1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/hpfs/dir.c 4 * 5 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 6 * 7 * directory VFS functions 8 */ 9 10 #include <linux/slab.h> 11 #include "hpfs_fn.h" 12 13 static int hpfs_dir_release(struct inode *inode, struct file *filp) 14 { 15 hpfs_lock(inode->i_sb); 16 hpfs_del_pos(inode, &filp->f_pos); 17 /*hpfs_write_if_changed(inode);*/ 18 hpfs_unlock(inode->i_sb); 19 return 0; 20 } 21 22 /* This is slow, but it's not used often */ 23 24 static loff_t hpfs_dir_lseek(struct file *filp, loff_t off, int whence) 25 { 26 loff_t new_off = off + (whence == 1 ? filp->f_pos : 0); 27 loff_t pos; 28 struct quad_buffer_head qbh; 29 struct inode *i = file_inode(filp); 30 struct hpfs_inode_info *hpfs_inode = hpfs_i(i); 31 struct super_block *s = i->i_sb; 32 33 /* Somebody else will have to figure out what to do here */ 34 if (whence == SEEK_DATA || whence == SEEK_HOLE) 35 return -EINVAL; 36 37 inode_lock(i); 38 hpfs_lock(s); 39 40 /*pr_info("dir lseek\n");*/ 41 if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok; 42 pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1; 43 while (pos != new_off) { 44 if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh); 45 else goto fail; 46 if (pos == 12) goto fail; 47 } 48 if (unlikely(hpfs_add_pos(i, &filp->f_pos) < 0)) { 49 hpfs_unlock(s); 50 inode_unlock(i); 51 return -ENOMEM; 52 } 53 ok: 54 filp->f_pos = new_off; 55 hpfs_unlock(s); 56 inode_unlock(i); 57 return new_off; 58 fail: 59 /*pr_warn("illegal lseek: %016llx\n", new_off);*/ 60 hpfs_unlock(s); 61 inode_unlock(i); 62 return -ESPIPE; 63 } 64 65 static int hpfs_readdir(struct file *file, struct dir_context *ctx) 66 { 67 struct inode *inode = file_inode(file); 68 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode); 69 struct quad_buffer_head qbh; 70 struct hpfs_dirent *de; 71 int lc; 72 loff_t next_pos; 73 unsigned char *tempname; 74 int c1, c2 = 0; 75 int ret = 0; 76 77 hpfs_lock(inode->i_sb); 78 79 if (hpfs_sb(inode->i_sb)->sb_chk) { 80 if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) { 81 ret = -EFSERROR; 82 goto out; 83 } 84 if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) { 85 ret = -EFSERROR; 86 goto out; 87 } 88 } 89 if (hpfs_sb(inode->i_sb)->sb_chk >= 2) { 90 struct buffer_head *bh; 91 struct fnode *fno; 92 int e = 0; 93 if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) { 94 ret = -EIOERROR; 95 goto out; 96 } 97 if (!fnode_is_dir(fno)) { 98 e = 1; 99 hpfs_error(inode->i_sb, "not a directory, fnode %08lx", 100 (unsigned long)inode->i_ino); 101 } 102 if (hpfs_inode->i_dno != le32_to_cpu(fno->u.external[0].disk_secno)) { 103 e = 1; 104 hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, le32_to_cpu(fno->u.external[0].disk_secno)); 105 } 106 brelse(bh); 107 if (e) { 108 ret = -EFSERROR; 109 goto out; 110 } 111 } 112 lc = hpfs_sb(inode->i_sb)->sb_lowercase; 113 if (ctx->pos == 12) { /* diff -r requires this (note, that diff -r */ 114 ctx->pos = 13; /* also fails on msdos filesystem in 2.0) */ 115 goto out; 116 } 117 if (ctx->pos == 13) { 118 ret = -ENOENT; 119 goto out; 120 } 121 122 while (1) { 123 again: 124 /* This won't work when cycle is longer than number of dirents 125 accepted by filldir, but what can I do? 126 maybe killall -9 ls helps */ 127 if (hpfs_sb(inode->i_sb)->sb_chk) 128 if (hpfs_stop_cycles(inode->i_sb, ctx->pos, &c1, &c2, "hpfs_readdir")) { 129 ret = -EFSERROR; 130 goto out; 131 } 132 if (ctx->pos == 12) 133 goto out; 134 if (ctx->pos == 3 || ctx->pos == 4 || ctx->pos == 5) { 135 pr_err("pos==%d\n", (int)ctx->pos); 136 goto out; 137 } 138 if (ctx->pos == 0) { 139 if (!dir_emit_dot(file, ctx)) 140 goto out; 141 ctx->pos = 11; 142 } 143 if (ctx->pos == 11) { 144 if (!dir_emit(ctx, "..", 2, hpfs_inode->i_parent_dir, DT_DIR)) 145 goto out; 146 ctx->pos = 1; 147 } 148 if (ctx->pos == 1) { 149 ret = hpfs_add_pos(inode, &file->f_pos); 150 if (unlikely(ret < 0)) 151 goto out; 152 ctx->pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1; 153 } 154 next_pos = ctx->pos; 155 if (!(de = map_pos_dirent(inode, &next_pos, &qbh))) { 156 ctx->pos = next_pos; 157 ret = -EIOERROR; 158 goto out; 159 } 160 if (de->first || de->last) { 161 if (hpfs_sb(inode->i_sb)->sb_chk) { 162 if (de->first && !de->last && (de->namelen != 2 163 || de ->name[0] != 1 || de->name[1] != 1)) 164 hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", (unsigned long)ctx->pos); 165 if (de->last && (de->namelen != 1 || de ->name[0] != 255)) 166 hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", (unsigned long)ctx->pos); 167 } 168 hpfs_brelse4(&qbh); 169 ctx->pos = next_pos; 170 goto again; 171 } 172 tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3); 173 if (!dir_emit(ctx, tempname, de->namelen, le32_to_cpu(de->fnode), DT_UNKNOWN)) { 174 if (tempname != de->name) kfree(tempname); 175 hpfs_brelse4(&qbh); 176 goto out; 177 } 178 ctx->pos = next_pos; 179 if (tempname != de->name) kfree(tempname); 180 hpfs_brelse4(&qbh); 181 } 182 out: 183 hpfs_unlock(inode->i_sb); 184 return ret; 185 } 186 187 /* 188 * lookup. Search the specified directory for the specified name, set 189 * *result to the corresponding inode. 190 * 191 * lookup uses the inode number to tell read_inode whether it is reading 192 * the inode of a directory or a file -- file ino's are odd, directory 193 * ino's are even. read_inode avoids i/o for file inodes; everything 194 * needed is up here in the directory. (And file fnodes are out in 195 * the boondocks.) 196 * 197 * - M.P.: this is over, sometimes we've got to read file's fnode for eas 198 * inode numbers are just fnode sector numbers; iget lock is used 199 * to tell read_inode to read fnode or not. 200 */ 201 202 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 203 { 204 const unsigned char *name = dentry->d_name.name; 205 unsigned len = dentry->d_name.len; 206 struct quad_buffer_head qbh; 207 struct hpfs_dirent *de; 208 ino_t ino; 209 int err; 210 struct inode *result = NULL; 211 struct hpfs_inode_info *hpfs_result; 212 213 hpfs_lock(dir->i_sb); 214 if ((err = hpfs_chk_name(name, &len))) { 215 if (err == -ENAMETOOLONG) { 216 hpfs_unlock(dir->i_sb); 217 return ERR_PTR(-ENAMETOOLONG); 218 } 219 goto end_add; 220 } 221 222 /* 223 * '.' and '..' will never be passed here. 224 */ 225 226 de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh); 227 228 /* 229 * This is not really a bailout, just means file not found. 230 */ 231 232 if (!de) goto end; 233 234 /* 235 * Get inode number, what we're after. 236 */ 237 238 ino = le32_to_cpu(de->fnode); 239 240 /* 241 * Go find or make an inode. 242 */ 243 244 result = iget_locked(dir->i_sb, ino); 245 if (!result) { 246 hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode"); 247 result = ERR_PTR(-ENOMEM); 248 goto bail1; 249 } 250 if (result->i_state & I_NEW) { 251 hpfs_init_inode(result); 252 if (de->directory) 253 hpfs_read_inode(result); 254 else if (le32_to_cpu(de->ea_size) && hpfs_sb(dir->i_sb)->sb_eas) 255 hpfs_read_inode(result); 256 else { 257 result->i_mode |= S_IFREG; 258 result->i_mode &= ~0111; 259 result->i_op = &hpfs_file_iops; 260 result->i_fop = &hpfs_file_ops; 261 set_nlink(result, 1); 262 } 263 unlock_new_inode(result); 264 } 265 hpfs_result = hpfs_i(result); 266 if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino; 267 268 if (de->has_acl || de->has_xtd_perm) if (!sb_rdonly(dir->i_sb)) { 269 hpfs_error(result->i_sb, "ACLs or XPERM found. This is probably HPFS386. This driver doesn't support it now. Send me some info on these structures"); 270 iput(result); 271 result = ERR_PTR(-EINVAL); 272 goto bail1; 273 } 274 275 /* 276 * Fill in the info from the directory if this is a newly created 277 * inode. 278 */ 279 280 if (!inode_get_ctime_sec(result)) { 281 time64_t csec = local_to_gmt(dir->i_sb, le32_to_cpu(de->creation_date)); 282 283 inode_set_ctime(result, csec ? csec : 1, 0); 284 inode_set_mtime(result, 285 local_to_gmt(dir->i_sb, le32_to_cpu(de->write_date)), 286 0); 287 inode_set_atime(result, 288 local_to_gmt(dir->i_sb, le32_to_cpu(de->read_date)), 289 0); 290 hpfs_result->i_ea_size = le32_to_cpu(de->ea_size); 291 if (!hpfs_result->i_ea_mode && de->read_only) 292 result->i_mode &= ~0222; 293 if (!de->directory) { 294 if (result->i_size == -1) { 295 result->i_size = le32_to_cpu(de->file_size); 296 result->i_data.a_ops = &hpfs_aops; 297 hpfs_i(result)->mmu_private = result->i_size; 298 /* 299 * i_blocks should count the fnode and any anodes. 300 * We count 1 for the fnode and don't bother about 301 * anodes -- the disk heads are on the directory band 302 * and we want them to stay there. 303 */ 304 result->i_blocks = 1 + ((result->i_size + 511) >> 9); 305 } 306 } 307 } 308 309 bail1: 310 hpfs_brelse4(&qbh); 311 312 /* 313 * Made it. 314 */ 315 316 end: 317 end_add: 318 hpfs_unlock(dir->i_sb); 319 return d_splice_alias(result, dentry); 320 } 321 322 const struct file_operations hpfs_dir_ops = 323 { 324 .llseek = hpfs_dir_lseek, 325 .read = generic_read_dir, 326 .iterate_shared = hpfs_readdir, 327 .release = hpfs_dir_release, 328 .fsync = hpfs_file_fsync, 329 .unlocked_ioctl = hpfs_ioctl, 330 .compat_ioctl = compat_ptr_ioctl, 331 }; 332