| /* |
| * linux/fs/affs/namei.c |
| * |
| * (c) 1996 Hans-Joachim Widmaier - Rewritten |
| * |
| * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem. |
| * |
| * (C) 1991 Linus Torvalds - minix filesystem |
| */ |
| |
| #include "affs.h" |
| |
| typedef int (*toupper_t)(int); |
| |
| static int affs_toupper(int ch); |
| static int affs_hash_dentry(const struct dentry *, struct qstr *); |
| static int affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry, |
| unsigned int len, const char *str, const struct qstr *name); |
| static int affs_intl_toupper(int ch); |
| static int affs_intl_hash_dentry(const struct dentry *, struct qstr *); |
| static int affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry, |
| unsigned int len, const char *str, const struct qstr *name); |
| |
| const struct dentry_operations affs_dentry_operations = { |
| .d_hash = affs_hash_dentry, |
| .d_compare = affs_compare_dentry, |
| }; |
| |
| const struct dentry_operations affs_intl_dentry_operations = { |
| .d_hash = affs_intl_hash_dentry, |
| .d_compare = affs_intl_compare_dentry, |
| }; |
| |
| |
| /* Simple toupper() for DOS\1 */ |
| |
| static int |
| affs_toupper(int ch) |
| { |
| return ch >= 'a' && ch <= 'z' ? ch -= ('a' - 'A') : ch; |
| } |
| |
| /* International toupper() for DOS\3 ("international") */ |
| |
| static int |
| affs_intl_toupper(int ch) |
| { |
| return (ch >= 'a' && ch <= 'z') || (ch >= 0xE0 |
| && ch <= 0xFE && ch != 0xF7) ? |
| ch - ('a' - 'A') : ch; |
| } |
| |
| static inline toupper_t |
| affs_get_toupper(struct super_block *sb) |
| { |
| return affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL) ? |
| affs_intl_toupper : affs_toupper; |
| } |
| |
| /* |
| * Note: the dentry argument is the parent dentry. |
| */ |
| static inline int |
| __affs_hash_dentry(struct qstr *qstr, toupper_t toupper, bool notruncate) |
| { |
| const u8 *name = qstr->name; |
| unsigned long hash; |
| int retval; |
| u32 len; |
| |
| retval = affs_check_name(qstr->name, qstr->len, notruncate); |
| if (retval) |
| return retval; |
| |
| hash = init_name_hash(); |
| len = min(qstr->len, AFFSNAMEMAX); |
| for (; len > 0; name++, len--) |
| hash = partial_name_hash(toupper(*name), hash); |
| qstr->hash = end_name_hash(hash); |
| |
| return 0; |
| } |
| |
| static int |
| affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr) |
| { |
| return __affs_hash_dentry(qstr, affs_toupper, |
| affs_nofilenametruncate(dentry)); |
| |
| } |
| |
| static int |
| affs_intl_hash_dentry(const struct dentry *dentry, struct qstr *qstr) |
| { |
| return __affs_hash_dentry(qstr, affs_intl_toupper, |
| affs_nofilenametruncate(dentry)); |
| |
| } |
| |
| static inline int __affs_compare_dentry(unsigned int len, |
| const char *str, const struct qstr *name, toupper_t toupper, |
| bool notruncate) |
| { |
| const u8 *aname = str; |
| const u8 *bname = name->name; |
| |
| /* |
| * 'str' is the name of an already existing dentry, so the name |
| * must be valid. 'name' must be validated first. |
| */ |
| |
| if (affs_check_name(name->name, name->len, notruncate)) |
| return 1; |
| |
| /* |
| * If the names are longer than the allowed 30 chars, |
| * the excess is ignored, so their length may differ. |
| */ |
| if (len >= AFFSNAMEMAX) { |
| if (name->len < AFFSNAMEMAX) |
| return 1; |
| len = AFFSNAMEMAX; |
| } else if (len != name->len) |
| return 1; |
| |
| for (; len > 0; len--) |
| if (toupper(*aname++) != toupper(*bname++)) |
| return 1; |
| |
| return 0; |
| } |
| |
| static int |
| affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry, |
| unsigned int len, const char *str, const struct qstr *name) |
| { |
| |
| return __affs_compare_dentry(len, str, name, affs_toupper, |
| affs_nofilenametruncate(parent)); |
| } |
| |
| static int |
| affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry, |
| unsigned int len, const char *str, const struct qstr *name) |
| { |
| return __affs_compare_dentry(len, str, name, affs_intl_toupper, |
| affs_nofilenametruncate(parent)); |
| |
| } |
| |
| /* |
| * NOTE! unlike strncmp, affs_match returns 1 for success, 0 for failure. |
| */ |
| |
| static inline int |
| affs_match(struct dentry *dentry, const u8 *name2, toupper_t toupper) |
| { |
| const u8 *name = dentry->d_name.name; |
| int len = dentry->d_name.len; |
| |
| if (len >= AFFSNAMEMAX) { |
| if (*name2 < AFFSNAMEMAX) |
| return 0; |
| len = AFFSNAMEMAX; |
| } else if (len != *name2) |
| return 0; |
| |
| for (name2++; len > 0; len--) |
| if (toupper(*name++) != toupper(*name2++)) |
| return 0; |
| return 1; |
| } |
| |
| int |
| affs_hash_name(struct super_block *sb, const u8 *name, unsigned int len) |
| { |
| toupper_t toupper = affs_get_toupper(sb); |
| u32 hash; |
| |
| hash = len = min(len, AFFSNAMEMAX); |
| for (; len > 0; len--) |
| hash = (hash * 13 + toupper(*name++)) & 0x7ff; |
| |
| return hash % AFFS_SB(sb)->s_hashsize; |
| } |
| |
| static struct buffer_head * |
| affs_find_entry(struct inode *dir, struct dentry *dentry) |
| { |
| struct super_block *sb = dir->i_sb; |
| struct buffer_head *bh; |
| toupper_t toupper = affs_get_toupper(sb); |
| u32 key; |
| |
| pr_debug("%s(\"%pd\")\n", __func__, dentry); |
| |
| bh = affs_bread(sb, dir->i_ino); |
| if (!bh) |
| return ERR_PTR(-EIO); |
| |
| key = be32_to_cpu(AFFS_HEAD(bh)->table[affs_hash_name(sb, dentry->d_name.name, dentry->d_name.len)]); |
| |
| for (;;) { |
| affs_brelse(bh); |
| if (key == 0) |
| return NULL; |
| bh = affs_bread(sb, key); |
| if (!bh) |
| return ERR_PTR(-EIO); |
| if (affs_match(dentry, AFFS_TAIL(sb, bh)->name, toupper)) |
| return bh; |
| key = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain); |
| } |
| } |
| |
| struct dentry * |
| affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) |
| { |
| struct super_block *sb = dir->i_sb; |
| struct buffer_head *bh; |
| struct inode *inode = NULL; |
| |
| pr_debug("%s(\"%pd\")\n", __func__, dentry); |
| |
| affs_lock_dir(dir); |
| bh = affs_find_entry(dir, dentry); |
| affs_unlock_dir(dir); |
| if (IS_ERR(bh)) |
| return ERR_CAST(bh); |
| if (bh) { |
| u32 ino = bh->b_blocknr; |
| |
| /* store the real header ino in d_fsdata for faster lookups */ |
| dentry->d_fsdata = (void *)(long)ino; |
| switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) { |
| //link to dirs disabled |
| //case ST_LINKDIR: |
| case ST_LINKFILE: |
| ino = be32_to_cpu(AFFS_TAIL(sb, bh)->original); |
| } |
| affs_brelse(bh); |
| inode = affs_iget(sb, ino); |
| if (IS_ERR(inode)) |
| return ERR_CAST(inode); |
| } |
| d_add(dentry, inode); |
| return NULL; |
| } |
| |
| int |
| affs_unlink(struct inode *dir, struct dentry *dentry) |
| { |
| pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino, |
| dentry->d_inode->i_ino, dentry); |
| |
| return affs_remove_header(dentry); |
| } |
| |
| int |
| affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) |
| { |
| struct super_block *sb = dir->i_sb; |
| struct inode *inode; |
| int error; |
| |
| pr_debug("%s(%lu,\"%pd\",0%ho)\n", |
| __func__, dir->i_ino, dentry, mode); |
| |
| inode = affs_new_inode(dir); |
| if (!inode) |
| return -ENOSPC; |
| |
| inode->i_mode = mode; |
| mode_to_prot(inode); |
| mark_inode_dirty(inode); |
| |
| inode->i_op = &affs_file_inode_operations; |
| inode->i_fop = &affs_file_operations; |
| inode->i_mapping->a_ops = affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS) ? |
| &affs_aops_ofs : &affs_aops; |
| error = affs_add_entry(dir, inode, dentry, ST_FILE); |
| if (error) { |
| clear_nlink(inode); |
| iput(inode); |
| return error; |
| } |
| return 0; |
| } |
| |
| int |
| affs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
| { |
| struct inode *inode; |
| int error; |
| |
| pr_debug("%s(%lu,\"%pd\",0%ho)\n", |
| __func__, dir->i_ino, dentry, mode); |
| |
| inode = affs_new_inode(dir); |
| if (!inode) |
| return -ENOSPC; |
| |
| inode->i_mode = S_IFDIR | mode; |
| mode_to_prot(inode); |
| |
| inode->i_op = &affs_dir_inode_operations; |
| inode->i_fop = &affs_dir_operations; |
| |
| error = affs_add_entry(dir, inode, dentry, ST_USERDIR); |
| if (error) { |
| clear_nlink(inode); |
| mark_inode_dirty(inode); |
| iput(inode); |
| return error; |
| } |
| return 0; |
| } |
| |
| int |
| affs_rmdir(struct inode *dir, struct dentry *dentry) |
| { |
| pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino, |
| dentry->d_inode->i_ino, dentry); |
| |
| return affs_remove_header(dentry); |
| } |
| |
| int |
| affs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) |
| { |
| struct super_block *sb = dir->i_sb; |
| struct buffer_head *bh; |
| struct inode *inode; |
| char *p; |
| int i, maxlen, error; |
| char c, lc; |
| |
| pr_debug("%s(%lu,\"%pd\" -> \"%s\")\n", |
| __func__, dir->i_ino, dentry, symname); |
| |
| maxlen = AFFS_SB(sb)->s_hashsize * sizeof(u32) - 1; |
| inode = affs_new_inode(dir); |
| if (!inode) |
| return -ENOSPC; |
| |
| inode->i_op = &affs_symlink_inode_operations; |
| inode->i_data.a_ops = &affs_symlink_aops; |
| inode->i_mode = S_IFLNK | 0777; |
| mode_to_prot(inode); |
| |
| error = -EIO; |
| bh = affs_bread(sb, inode->i_ino); |
| if (!bh) |
| goto err; |
| i = 0; |
| p = (char *)AFFS_HEAD(bh)->table; |
| lc = '/'; |
| if (*symname == '/') { |
| struct affs_sb_info *sbi = AFFS_SB(sb); |
| while (*symname == '/') |
| symname++; |
| spin_lock(&sbi->symlink_lock); |
| while (sbi->s_volume[i]) /* Cannot overflow */ |
| *p++ = sbi->s_volume[i++]; |
| spin_unlock(&sbi->symlink_lock); |
| } |
| while (i < maxlen && (c = *symname++)) { |
| if (c == '.' && lc == '/' && *symname == '.' && symname[1] == '/') { |
| *p++ = '/'; |
| i++; |
| symname += 2; |
| lc = '/'; |
| } else if (c == '.' && lc == '/' && *symname == '/') { |
| symname++; |
| lc = '/'; |
| } else { |
| *p++ = c; |
| lc = c; |
| i++; |
| } |
| if (lc == '/') |
| while (*symname == '/') |
| symname++; |
| } |
| *p = 0; |
| mark_buffer_dirty_inode(bh, inode); |
| affs_brelse(bh); |
| mark_inode_dirty(inode); |
| |
| error = affs_add_entry(dir, inode, dentry, ST_SOFTLINK); |
| if (error) |
| goto err; |
| |
| return 0; |
| |
| err: |
| clear_nlink(inode); |
| mark_inode_dirty(inode); |
| iput(inode); |
| return error; |
| } |
| |
| int |
| affs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) |
| { |
| struct inode *inode = old_dentry->d_inode; |
| |
| pr_debug("%s(%lu, %lu, \"%pd\")\n", __func__, inode->i_ino, dir->i_ino, |
| dentry); |
| |
| return affs_add_entry(dir, inode, dentry, ST_LINKFILE); |
| } |
| |
| int |
| affs_rename(struct inode *old_dir, struct dentry *old_dentry, |
| struct inode *new_dir, struct dentry *new_dentry) |
| { |
| struct super_block *sb = old_dir->i_sb; |
| struct buffer_head *bh = NULL; |
| int retval; |
| |
| pr_debug("%s(old=%lu,\"%pd\" to new=%lu,\"%pd\")\n", __func__, |
| old_dir->i_ino, old_dentry, new_dir->i_ino, new_dentry); |
| |
| retval = affs_check_name(new_dentry->d_name.name, |
| new_dentry->d_name.len, |
| affs_nofilenametruncate(old_dentry)); |
| |
| if (retval) |
| return retval; |
| |
| /* Unlink destination if it already exists */ |
| if (new_dentry->d_inode) { |
| retval = affs_remove_header(new_dentry); |
| if (retval) |
| return retval; |
| } |
| |
| bh = affs_bread(sb, old_dentry->d_inode->i_ino); |
| if (!bh) |
| return -EIO; |
| |
| /* Remove header from its parent directory. */ |
| affs_lock_dir(old_dir); |
| retval = affs_remove_hash(old_dir, bh); |
| affs_unlock_dir(old_dir); |
| if (retval) |
| goto done; |
| |
| /* And insert it into the new directory with the new name. */ |
| affs_copy_name(AFFS_TAIL(sb, bh)->name, new_dentry); |
| affs_fix_checksum(sb, bh); |
| affs_lock_dir(new_dir); |
| retval = affs_insert_hash(new_dir, bh); |
| affs_unlock_dir(new_dir); |
| /* TODO: move it back to old_dir, if error? */ |
| |
| done: |
| mark_buffer_dirty_inode(bh, retval ? old_dir : new_dir); |
| affs_brelse(bh); |
| return retval; |
| } |