--- /dev/null
+/*
+ * 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 "adfs.h"
+
+/*
+ * For future. This should probably be per-directory.
+ */
+static DEFINE_RWLOCK(adfs_dir_lock);
+
+static int
+adfs_readdir(struct file *file, struct dir_context *ctx)
+{
+ struct inode *inode = file_inode(file);
+ 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;
+
+ if (ctx->pos >> 32)
+ return 0;
+
+ ret = ops->read(sb, inode->i_ino, inode->i_size, &dir);
+ if (ret)
+ return ret;
+
+ if (ctx->pos == 0) {
+ if (!dir_emit_dot(file, ctx))
+ goto free_out;
+ ctx->pos = 1;
+ }
+ if (ctx->pos == 1) {
+ if (!dir_emit(ctx, "..", 2, dir.parent_id, DT_DIR))
+ goto free_out;
+ ctx->pos = 2;
+ }
+
+ read_lock(&adfs_dir_lock);
+
+ ret = ops->setpos(&dir, ctx->pos - 2);
+ if (ret)
+ goto unlock_out;
+ while (ops->getnext(&dir, &obj) == 0) {
+ if (!dir_emit(ctx, obj.name, obj.name_len,
+ obj.file_id, DT_UNKNOWN))
+ break;
+ ctx->pos++;
+ }
+
+unlock_out:
+ read_unlock(&adfs_dir_lock);
+
+free_out:
+ ops->free(&dir);
+ 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 %x)\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,
+ .iterate = adfs_readdir,
+ .fsync = generic_file_fsync,
+};
+
+static int
+adfs_hash(const 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(const struct dentry *parent, const struct dentry *dentry,
+ 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, unsigned int flags)
+{
+ struct inode *inode = NULL;
+ struct object_info obj;
+ int error;
+
+ 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;
+ }
+ 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,
+};
Code Review / kvmfornfv.git / blobdiff