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1// SPDX-License-Identifier: GPL-2.02/*3 * linux/fs/ufs/namei.c4 *5 * Migration to usage of "page cache" on May 2006 by6 * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base.7 *8 * Copyright (C) 19989 * Daniel Pirkl <daniel.pirkl@email.cz>10 * Charles University, Faculty of Mathematics and Physics11 *12 * from13 *14 * linux/fs/ext2/namei.c15 *16 * Copyright (C) 1992, 1993, 1994, 199517 * Remy Card (card@masi.ibp.fr)18 * Laboratoire MASI - Institut Blaise Pascal19 * Universite Pierre et Marie Curie (Paris VI)20 *21 * from22 *23 * linux/fs/minix/namei.c24 *25 * Copyright (C) 1991, 1992 Linus Torvalds26 *27 * Big-endian to little-endian byte-swapping/bitmaps by28 * David S. Miller (davem@caip.rutgers.edu), 199529 */30 31#include <linux/time.h>32#include <linux/fs.h>33 34#include "ufs_fs.h"35#include "ufs.h"36#include "util.h"37 38static inline int ufs_add_nondir(struct dentry *dentry, struct inode *inode)39{40 int err = ufs_add_link(dentry, inode);41 if (!err) {42 d_instantiate_new(dentry, inode);43 return 0;44 }45 inode_dec_link_count(inode);46 discard_new_inode(inode);47 return err;48}49 50static struct dentry *ufs_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)51{52 struct inode * inode = NULL;53 ino_t ino;54 55 if (dentry->d_name.len > UFS_MAXNAMLEN)56 return ERR_PTR(-ENAMETOOLONG);57 58 ino = ufs_inode_by_name(dir, &dentry->d_name);59 if (ino)60 inode = ufs_iget(dir->i_sb, ino);61 return d_splice_alias(inode, dentry);62}63 64/*65 * By the time this is called, we already have created66 * the directory cache entry for the new file, but it67 * is so far negative - it has no inode.68 *69 * If the create succeeds, we fill in the inode information70 * with d_instantiate(). 71 */72static int ufs_create (struct mnt_idmap * idmap,73 struct inode * dir, struct dentry * dentry, umode_t mode,74 bool excl)75{76 struct inode *inode;77 78 inode = ufs_new_inode(dir, mode);79 if (IS_ERR(inode))80 return PTR_ERR(inode);81 82 inode->i_op = &ufs_file_inode_operations;83 inode->i_fop = &ufs_file_operations;84 inode->i_mapping->a_ops = &ufs_aops;85 mark_inode_dirty(inode);86 return ufs_add_nondir(dentry, inode);87}88 89static int ufs_mknod(struct mnt_idmap *idmap, struct inode *dir,90 struct dentry *dentry, umode_t mode, dev_t rdev)91{92 struct inode *inode;93 int err;94 95 if (!old_valid_dev(rdev))96 return -EINVAL;97 98 inode = ufs_new_inode(dir, mode);99 err = PTR_ERR(inode);100 if (!IS_ERR(inode)) {101 init_special_inode(inode, mode, rdev);102 ufs_set_inode_dev(inode->i_sb, UFS_I(inode), rdev);103 mark_inode_dirty(inode);104 err = ufs_add_nondir(dentry, inode);105 }106 return err;107}108 109static int ufs_symlink (struct mnt_idmap * idmap, struct inode * dir,110 struct dentry * dentry, const char * symname)111{112 struct super_block * sb = dir->i_sb;113 int err;114 unsigned l = strlen(symname)+1;115 struct inode * inode;116 117 if (l > sb->s_blocksize)118 return -ENAMETOOLONG;119 120 inode = ufs_new_inode(dir, S_IFLNK | S_IRWXUGO);121 err = PTR_ERR(inode);122 if (IS_ERR(inode))123 return err;124 125 if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) {126 /* slow symlink */127 inode->i_op = &page_symlink_inode_operations;128 inode_nohighmem(inode);129 inode->i_mapping->a_ops = &ufs_aops;130 err = page_symlink(inode, symname, l);131 if (err)132 goto out_fail;133 } else {134 /* fast symlink */135 inode->i_op = &simple_symlink_inode_operations;136 inode->i_link = (char *)UFS_I(inode)->i_u1.i_symlink;137 memcpy(inode->i_link, symname, l);138 inode->i_size = l-1;139 }140 mark_inode_dirty(inode);141 142 return ufs_add_nondir(dentry, inode);143 144out_fail:145 inode_dec_link_count(inode);146 discard_new_inode(inode);147 return err;148}149 150static int ufs_link (struct dentry * old_dentry, struct inode * dir,151 struct dentry *dentry)152{153 struct inode *inode = d_inode(old_dentry);154 int error;155 156 inode_set_ctime_current(inode);157 inode_inc_link_count(inode);158 ihold(inode);159 160 error = ufs_add_link(dentry, inode);161 if (error) {162 inode_dec_link_count(inode);163 iput(inode);164 } else165 d_instantiate(dentry, inode);166 return error;167}168 169static int ufs_mkdir(struct mnt_idmap * idmap, struct inode * dir,170 struct dentry * dentry, umode_t mode)171{172 struct inode * inode;173 int err;174 175 inode_inc_link_count(dir);176 177 inode = ufs_new_inode(dir, S_IFDIR|mode);178 err = PTR_ERR(inode);179 if (IS_ERR(inode))180 goto out_dir;181 182 inode->i_op = &ufs_dir_inode_operations;183 inode->i_fop = &ufs_dir_operations;184 inode->i_mapping->a_ops = &ufs_aops;185 186 inode_inc_link_count(inode);187 188 err = ufs_make_empty(inode, dir);189 if (err)190 goto out_fail;191 192 err = ufs_add_link(dentry, inode);193 if (err)194 goto out_fail;195 196 d_instantiate_new(dentry, inode);197 return 0;198 199out_fail:200 inode_dec_link_count(inode);201 inode_dec_link_count(inode);202 discard_new_inode(inode);203out_dir:204 inode_dec_link_count(dir);205 return err;206}207 208static int ufs_unlink(struct inode *dir, struct dentry *dentry)209{210 struct inode * inode = d_inode(dentry);211 struct ufs_dir_entry *de;212 struct folio *folio;213 int err = -ENOENT;214 215 de = ufs_find_entry(dir, &dentry->d_name, &folio);216 if (!de)217 goto out;218 219 err = ufs_delete_entry(dir, de, folio);220 if (err)221 goto out;222 223 inode_set_ctime_to_ts(inode, inode_get_ctime(dir));224 inode_dec_link_count(inode);225 err = 0;226out:227 return err;228}229 230static int ufs_rmdir (struct inode * dir, struct dentry *dentry)231{232 struct inode * inode = d_inode(dentry);233 int err= -ENOTEMPTY;234 235 if (ufs_empty_dir (inode)) {236 err = ufs_unlink(dir, dentry);237 if (!err) {238 inode->i_size = 0;239 inode_dec_link_count(inode);240 inode_dec_link_count(dir);241 }242 }243 return err;244}245 246static int ufs_rename(struct mnt_idmap *idmap, struct inode *old_dir,247 struct dentry *old_dentry, struct inode *new_dir,248 struct dentry *new_dentry, unsigned int flags)249{250 struct inode *old_inode = d_inode(old_dentry);251 struct inode *new_inode = d_inode(new_dentry);252 struct folio *dir_folio = NULL;253 struct ufs_dir_entry * dir_de = NULL;254 struct folio *old_folio;255 struct ufs_dir_entry *old_de;256 int err = -ENOENT;257 258 if (flags & ~RENAME_NOREPLACE)259 return -EINVAL;260 261 old_de = ufs_find_entry(old_dir, &old_dentry->d_name, &old_folio);262 if (!old_de)263 goto out;264 265 if (S_ISDIR(old_inode->i_mode)) {266 err = -EIO;267 dir_de = ufs_dotdot(old_inode, &dir_folio);268 if (!dir_de)269 goto out_old;270 }271 272 if (new_inode) {273 struct folio *new_folio;274 struct ufs_dir_entry *new_de;275 276 err = -ENOTEMPTY;277 if (dir_de && !ufs_empty_dir(new_inode))278 goto out_dir;279 280 err = -ENOENT;281 new_de = ufs_find_entry(new_dir, &new_dentry->d_name, &new_folio);282 if (!new_de)283 goto out_dir;284 ufs_set_link(new_dir, new_de, new_folio, old_inode, 1);285 inode_set_ctime_current(new_inode);286 if (dir_de)287 drop_nlink(new_inode);288 inode_dec_link_count(new_inode);289 } else {290 err = ufs_add_link(new_dentry, old_inode);291 if (err)292 goto out_dir;293 if (dir_de)294 inode_inc_link_count(new_dir);295 }296 297 /*298 * Like most other Unix systems, set the ctime for inodes on a299 * rename.300 */301 inode_set_ctime_current(old_inode);302 303 ufs_delete_entry(old_dir, old_de, old_folio);304 mark_inode_dirty(old_inode);305 306 if (dir_de) {307 if (old_dir != new_dir)308 ufs_set_link(old_inode, dir_de, dir_folio, new_dir, 0);309 else310 folio_release_kmap(dir_folio, dir_de);311 inode_dec_link_count(old_dir);312 }313 return 0;314 315 316out_dir:317 if (dir_de)318 folio_release_kmap(dir_folio, dir_de);319out_old:320 folio_release_kmap(old_folio, old_de);321out:322 return err;323}324 325const struct inode_operations ufs_dir_inode_operations = {326 .create = ufs_create,327 .lookup = ufs_lookup,328 .link = ufs_link,329 .unlink = ufs_unlink,330 .symlink = ufs_symlink,331 .mkdir = ufs_mkdir,332 .rmdir = ufs_rmdir,333 .mknod = ufs_mknod,334 .rename = ufs_rename,335};336