| /* |
| * linux/fs/adfs/dir.c |
| * |
| * Copyright (C) 1999-2000 Russell King |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * Common directory handling for ADFS |
| */ |
| #include <linux/smp_lock.h> |
| #include "adfs.h" |
| |
| /* |
| * For future. This should probably be per-directory. |
| */ |
| static DEFINE_RWLOCK(adfs_dir_lock); |
| |
| static int |
| adfs_readdir(struct file *filp, void *dirent, filldir_t filldir) |
| { |
| struct inode *inode = filp->f_path.dentry->d_inode; |
| struct super_block *sb = inode->i_sb; |
| struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; |
| struct object_info obj; |
| struct adfs_dir dir; |
| int ret = 0; |
| |
| lock_kernel(); |
| |
| if (filp->f_pos >> 32) |
| goto out; |
| |
| ret = ops->read(sb, inode->i_ino, inode->i_size, &dir); |
| if (ret) |
| goto out; |
| |
| switch ((unsigned long)filp->f_pos) { |
| case 0: |
| if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) |
| goto free_out; |
| filp->f_pos += 1; |
| |
| case 1: |
| if (filldir(dirent, "..", 2, 1, dir.parent_id, DT_DIR) < 0) |
| goto free_out; |
| filp->f_pos += 1; |
| |
| default: |
| break; |
| } |
| |
| read_lock(&adfs_dir_lock); |
| |
| ret = ops->setpos(&dir, filp->f_pos - 2); |
| if (ret) |
| goto unlock_out; |
| while (ops->getnext(&dir, &obj) == 0) { |
| if (filldir(dirent, obj.name, obj.name_len, |
| filp->f_pos, obj.file_id, DT_UNKNOWN) < 0) |
| goto unlock_out; |
| filp->f_pos += 1; |
| } |
| |
| unlock_out: |
| read_unlock(&adfs_dir_lock); |
| |
| free_out: |
| ops->free(&dir); |
| |
| out: |
| unlock_kernel(); |
| return ret; |
| } |
| |
| int |
| adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait) |
| { |
| int ret = -EINVAL; |
| #ifdef CONFIG_ADFS_FS_RW |
| struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; |
| struct adfs_dir dir; |
| |
| printk(KERN_INFO "adfs_dir_update: object %06X in dir %06X\n", |
| obj->file_id, obj->parent_id); |
| |
| if (!ops->update) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| ret = ops->read(sb, obj->parent_id, 0, &dir); |
| if (ret) |
| goto out; |
| |
| write_lock(&adfs_dir_lock); |
| ret = ops->update(&dir, obj); |
| write_unlock(&adfs_dir_lock); |
| |
| if (wait) { |
| int err = ops->sync(&dir); |
| if (!ret) |
| ret = err; |
| } |
| |
| ops->free(&dir); |
| out: |
| #endif |
| return ret; |
| } |
| |
| static int |
| adfs_match(struct qstr *name, struct object_info *obj) |
| { |
| int i; |
| |
| if (name->len != obj->name_len) |
| return 0; |
| |
| for (i = 0; i < name->len; i++) { |
| char c1, c2; |
| |
| c1 = name->name[i]; |
| c2 = obj->name[i]; |
| |
| if (c1 >= 'A' && c1 <= 'Z') |
| c1 += 'a' - 'A'; |
| if (c2 >= 'A' && c2 <= 'Z') |
| c2 += 'a' - 'A'; |
| |
| if (c1 != c2) |
| return 0; |
| } |
| return 1; |
| } |
| |
| static int |
| adfs_dir_lookup_byname(struct inode *inode, struct qstr *name, struct object_info *obj) |
| { |
| struct super_block *sb = inode->i_sb; |
| struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir; |
| struct adfs_dir dir; |
| int ret; |
| |
| ret = ops->read(sb, inode->i_ino, inode->i_size, &dir); |
| if (ret) |
| goto out; |
| |
| if (ADFS_I(inode)->parent_id != dir.parent_id) { |
| adfs_error(sb, "parent directory changed under me! (%lx but got %lx)\n", |
| ADFS_I(inode)->parent_id, dir.parent_id); |
| ret = -EIO; |
| goto free_out; |
| } |
| |
| obj->parent_id = inode->i_ino; |
| |
| /* |
| * '.' is handled by reserved_lookup() in fs/namei.c |
| */ |
| if (name->len == 2 && name->name[0] == '.' && name->name[1] == '.') { |
| /* |
| * Currently unable to fill in the rest of 'obj', |
| * but this is better than nothing. We need to |
| * ascend one level to find it's parent. |
| */ |
| obj->name_len = 0; |
| obj->file_id = obj->parent_id; |
| goto free_out; |
| } |
| |
| read_lock(&adfs_dir_lock); |
| |
| ret = ops->setpos(&dir, 0); |
| if (ret) |
| goto unlock_out; |
| |
| ret = -ENOENT; |
| while (ops->getnext(&dir, obj) == 0) { |
| if (adfs_match(name, obj)) { |
| ret = 0; |
| break; |
| } |
| } |
| |
| unlock_out: |
| read_unlock(&adfs_dir_lock); |
| |
| free_out: |
| ops->free(&dir); |
| out: |
| return ret; |
| } |
| |
| const struct file_operations adfs_dir_operations = { |
| .read = generic_read_dir, |
| .llseek = generic_file_llseek, |
| .readdir = adfs_readdir, |
| .fsync = generic_file_fsync, |
| }; |
| |
| static int |
| adfs_hash(const struct dentry *parent, const struct inode *inode, |
| struct qstr *qstr) |
| { |
| const unsigned int name_len = ADFS_SB(parent->d_sb)->s_namelen; |
| const unsigned char *name; |
| unsigned long hash; |
| int i; |
| |
| if (qstr->len < name_len) |
| return 0; |
| |
| /* |
| * Truncate the name in place, avoids |
| * having to define a compare function. |
| */ |
| qstr->len = i = name_len; |
| name = qstr->name; |
| hash = init_name_hash(); |
| while (i--) { |
| char c; |
| |
| c = *name++; |
| if (c >= 'A' && c <= 'Z') |
| c += 'a' - 'A'; |
| |
| hash = partial_name_hash(c, hash); |
| } |
| qstr->hash = end_name_hash(hash); |
| |
| return 0; |
| } |
| |
| /* |
| * Compare two names, taking note of the name length |
| * requirements of the underlying filesystem. |
| */ |
| static int |
| adfs_compare(const struct dentry *parent, const struct inode *pinode, |
| const struct dentry *dentry, const struct inode *inode, |
| unsigned int len, const char *str, const struct qstr *name) |
| { |
| int i; |
| |
| if (len != name->len) |
| return 1; |
| |
| for (i = 0; i < name->len; i++) { |
| char a, b; |
| |
| a = str[i]; |
| b = name->name[i]; |
| |
| if (a >= 'A' && a <= 'Z') |
| a += 'a' - 'A'; |
| if (b >= 'A' && b <= 'Z') |
| b += 'a' - 'A'; |
| |
| if (a != b) |
| return 1; |
| } |
| return 0; |
| } |
| |
| const struct dentry_operations adfs_dentry_operations = { |
| .d_hash = adfs_hash, |
| .d_compare = adfs_compare, |
| }; |
| |
| static struct dentry * |
| adfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) |
| { |
| struct inode *inode = NULL; |
| struct object_info obj; |
| int error; |
| |
| dentry->d_op = &adfs_dentry_operations; |
| lock_kernel(); |
| error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj); |
| if (error == 0) { |
| error = -EACCES; |
| /* |
| * This only returns NULL if get_empty_inode |
| * fails. |
| */ |
| inode = adfs_iget(dir->i_sb, &obj); |
| if (inode) |
| error = 0; |
| } |
| unlock_kernel(); |
| d_add(dentry, inode); |
| return ERR_PTR(error); |
| } |
| |
| /* |
| * directories can handle most operations... |
| */ |
| const struct inode_operations adfs_dir_inode_operations = { |
| .lookup = adfs_lookup, |
| .setattr = adfs_notify_change, |
| }; |