/* * 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/config.h> #include <linux/errno.h> #include <linux/fs.h> #include <linux/adfs_fs.h> #include <linux/time.h> #include <linux/stat.h> #include <linux/spinlock.h> #include <linux/smp_lock.h> #include <linux/buffer_head.h> /* for file_fsync() */ #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_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 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); 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; } struct file_operations adfs_dir_operations = { .read = generic_read_dir, .readdir = adfs_readdir, .fsync = file_fsync, }; static int adfs_hash(struct dentry *parent, 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(struct dentry *parent, struct qstr *entry, struct qstr *name) { int i; if (entry->len != name->len) return 1; for (i = 0; i < name->len; i++) { char a, b; a = entry->name[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; } 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... */ struct inode_operations adfs_dir_inode_operations = { .lookup = adfs_lookup, .setattr = adfs_notify_change, };