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-rw-r--r--fs/openpromfs/inode.c471
1 files changed, 471 insertions, 0 deletions
diff --git a/fs/openpromfs/inode.c b/fs/openpromfs/inode.c
new file mode 100644
index 000000000..15e4500cd
--- /dev/null
+++ b/fs/openpromfs/inode.c
@@ -0,0 +1,471 @@
+/* inode.c: /proc/openprom handling routines
+ *
+ * Copyright (C) 1996-1999 Jakub Jelinek (jakub@redhat.com)
+ * Copyright (C) 1998 Eddie C. Dost (ecd@skynet.be)
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/magic.h>
+
+#include <asm/openprom.h>
+#include <asm/oplib.h>
+#include <asm/prom.h>
+#include <asm/uaccess.h>
+
+static DEFINE_MUTEX(op_mutex);
+
+#define OPENPROM_ROOT_INO 0
+
+enum op_inode_type {
+ op_inode_node,
+ op_inode_prop,
+};
+
+union op_inode_data {
+ struct device_node *node;
+ struct property *prop;
+};
+
+struct op_inode_info {
+ struct inode vfs_inode;
+ enum op_inode_type type;
+ union op_inode_data u;
+};
+
+static struct inode *openprom_iget(struct super_block *sb, ino_t ino);
+
+static inline struct op_inode_info *OP_I(struct inode *inode)
+{
+ return container_of(inode, struct op_inode_info, vfs_inode);
+}
+
+static int is_string(unsigned char *p, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++) {
+ unsigned char val = p[i];
+
+ if ((i && !val) ||
+ (val >= ' ' && val <= '~'))
+ continue;
+
+ return 0;
+ }
+
+ return 1;
+}
+
+static int property_show(struct seq_file *f, void *v)
+{
+ struct property *prop = f->private;
+ void *pval;
+ int len;
+
+ len = prop->length;
+ pval = prop->value;
+
+ if (is_string(pval, len)) {
+ while (len > 0) {
+ int n = strlen(pval);
+
+ seq_printf(f, "%s", (char *) pval);
+
+ /* Skip over the NULL byte too. */
+ pval += n + 1;
+ len -= n + 1;
+
+ if (len > 0)
+ seq_printf(f, " + ");
+ }
+ } else {
+ if (len & 3) {
+ while (len) {
+ len--;
+ if (len)
+ seq_printf(f, "%02x.",
+ *(unsigned char *) pval);
+ else
+ seq_printf(f, "%02x",
+ *(unsigned char *) pval);
+ pval++;
+ }
+ } else {
+ while (len >= 4) {
+ len -= 4;
+
+ if (len)
+ seq_printf(f, "%08x.",
+ *(unsigned int *) pval);
+ else
+ seq_printf(f, "%08x",
+ *(unsigned int *) pval);
+ pval += 4;
+ }
+ }
+ }
+ seq_printf(f, "\n");
+
+ return 0;
+}
+
+static void *property_start(struct seq_file *f, loff_t *pos)
+{
+ if (*pos == 0)
+ return pos;
+ return NULL;
+}
+
+static void *property_next(struct seq_file *f, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return NULL;
+}
+
+static void property_stop(struct seq_file *f, void *v)
+{
+ /* Nothing to do */
+}
+
+static const struct seq_operations property_op = {
+ .start = property_start,
+ .next = property_next,
+ .stop = property_stop,
+ .show = property_show
+};
+
+static int property_open(struct inode *inode, struct file *file)
+{
+ struct op_inode_info *oi = OP_I(inode);
+ int ret;
+
+ BUG_ON(oi->type != op_inode_prop);
+
+ ret = seq_open(file, &property_op);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = oi->u.prop;
+ }
+ return ret;
+}
+
+static const struct file_operations openpromfs_prop_ops = {
+ .open = property_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int openpromfs_readdir(struct file *, struct dir_context *);
+
+static const struct file_operations openprom_operations = {
+ .read = generic_read_dir,
+ .iterate = openpromfs_readdir,
+ .llseek = generic_file_llseek,
+};
+
+static struct dentry *openpromfs_lookup(struct inode *, struct dentry *, unsigned int);
+
+static const struct inode_operations openprom_inode_operations = {
+ .lookup = openpromfs_lookup,
+};
+
+static struct dentry *openpromfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+ struct op_inode_info *ent_oi, *oi = OP_I(dir);
+ struct device_node *dp, *child;
+ struct property *prop;
+ enum op_inode_type ent_type;
+ union op_inode_data ent_data;
+ const char *name;
+ struct inode *inode;
+ unsigned int ino;
+ int len;
+
+ BUG_ON(oi->type != op_inode_node);
+
+ dp = oi->u.node;
+
+ name = dentry->d_name.name;
+ len = dentry->d_name.len;
+
+ mutex_lock(&op_mutex);
+
+ child = dp->child;
+ while (child) {
+ int n = strlen(child->path_component_name);
+
+ if (len == n &&
+ !strncmp(child->path_component_name, name, len)) {
+ ent_type = op_inode_node;
+ ent_data.node = child;
+ ino = child->unique_id;
+ goto found;
+ }
+ child = child->sibling;
+ }
+
+ prop = dp->properties;
+ while (prop) {
+ int n = strlen(prop->name);
+
+ if (len == n && !strncmp(prop->name, name, len)) {
+ ent_type = op_inode_prop;
+ ent_data.prop = prop;
+ ino = prop->unique_id;
+ goto found;
+ }
+
+ prop = prop->next;
+ }
+
+ mutex_unlock(&op_mutex);
+ return ERR_PTR(-ENOENT);
+
+found:
+ inode = openprom_iget(dir->i_sb, ino);
+ mutex_unlock(&op_mutex);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ ent_oi = OP_I(inode);
+ ent_oi->type = ent_type;
+ ent_oi->u = ent_data;
+
+ switch (ent_type) {
+ case op_inode_node:
+ inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
+ inode->i_op = &openprom_inode_operations;
+ inode->i_fop = &openprom_operations;
+ set_nlink(inode, 2);
+ break;
+ case op_inode_prop:
+ if (!strcmp(dp->name, "options") && (len == 17) &&
+ !strncmp (name, "security-password", 17))
+ inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
+ else
+ inode->i_mode = S_IFREG | S_IRUGO;
+ inode->i_fop = &openpromfs_prop_ops;
+ set_nlink(inode, 1);
+ inode->i_size = ent_oi->u.prop->length;
+ break;
+ }
+
+ d_add(dentry, inode);
+ return NULL;
+}
+
+static int openpromfs_readdir(struct file *file, struct dir_context *ctx)
+{
+ struct inode *inode = file_inode(file);
+ struct op_inode_info *oi = OP_I(inode);
+ struct device_node *dp = oi->u.node;
+ struct device_node *child;
+ struct property *prop;
+ int i;
+
+ mutex_lock(&op_mutex);
+
+ if (ctx->pos == 0) {
+ if (!dir_emit(ctx, ".", 1, inode->i_ino, DT_DIR))
+ goto out;
+ ctx->pos = 1;
+ }
+ if (ctx->pos == 1) {
+ if (!dir_emit(ctx, "..", 2,
+ (dp->parent == NULL ?
+ OPENPROM_ROOT_INO :
+ dp->parent->unique_id), DT_DIR))
+ goto out;
+ ctx->pos = 2;
+ }
+ i = ctx->pos - 2;
+
+ /* First, the children nodes as directories. */
+ child = dp->child;
+ while (i && child) {
+ child = child->sibling;
+ i--;
+ }
+ while (child) {
+ if (!dir_emit(ctx,
+ child->path_component_name,
+ strlen(child->path_component_name),
+ child->unique_id, DT_DIR))
+ goto out;
+
+ ctx->pos++;
+ child = child->sibling;
+ }
+
+ /* Next, the properties as files. */
+ prop = dp->properties;
+ while (i && prop) {
+ prop = prop->next;
+ i--;
+ }
+ while (prop) {
+ if (!dir_emit(ctx, prop->name, strlen(prop->name),
+ prop->unique_id, DT_REG))
+ goto out;
+
+ ctx->pos++;
+ prop = prop->next;
+ }
+
+out:
+ mutex_unlock(&op_mutex);
+ return 0;
+}
+
+static struct kmem_cache *op_inode_cachep;
+
+static struct inode *openprom_alloc_inode(struct super_block *sb)
+{
+ struct op_inode_info *oi;
+
+ oi = kmem_cache_alloc(op_inode_cachep, GFP_KERNEL);
+ if (!oi)
+ return NULL;
+
+ return &oi->vfs_inode;
+}
+
+static void openprom_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ kmem_cache_free(op_inode_cachep, OP_I(inode));
+}
+
+static void openprom_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, openprom_i_callback);
+}
+
+static struct inode *openprom_iget(struct super_block *sb, ino_t ino)
+{
+ struct inode *inode;
+
+ inode = iget_locked(sb, ino);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ if (inode->i_state & I_NEW) {
+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+ if (inode->i_ino == OPENPROM_ROOT_INO) {
+ inode->i_op = &openprom_inode_operations;
+ inode->i_fop = &openprom_operations;
+ inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
+ }
+ unlock_new_inode(inode);
+ }
+ return inode;
+}
+
+static int openprom_remount(struct super_block *sb, int *flags, char *data)
+{
+ sync_filesystem(sb);
+ *flags |= MS_NOATIME;
+ return 0;
+}
+
+static const struct super_operations openprom_sops = {
+ .alloc_inode = openprom_alloc_inode,
+ .destroy_inode = openprom_destroy_inode,
+ .statfs = simple_statfs,
+ .remount_fs = openprom_remount,
+};
+
+static int openprom_fill_super(struct super_block *s, void *data, int silent)
+{
+ struct inode *root_inode;
+ struct op_inode_info *oi;
+ int ret;
+
+ s->s_flags |= MS_NOATIME;
+ s->s_blocksize = 1024;
+ s->s_blocksize_bits = 10;
+ s->s_magic = OPENPROM_SUPER_MAGIC;
+ s->s_op = &openprom_sops;
+ s->s_time_gran = 1;
+ root_inode = openprom_iget(s, OPENPROM_ROOT_INO);
+ if (IS_ERR(root_inode)) {
+ ret = PTR_ERR(root_inode);
+ goto out_no_root;
+ }
+
+ oi = OP_I(root_inode);
+ oi->type = op_inode_node;
+ oi->u.node = of_find_node_by_path("/");
+
+ s->s_root = d_make_root(root_inode);
+ if (!s->s_root)
+ goto out_no_root_dentry;
+ return 0;
+
+out_no_root_dentry:
+ ret = -ENOMEM;
+out_no_root:
+ printk("openprom_fill_super: get root inode failed\n");
+ return ret;
+}
+
+static struct dentry *openprom_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return mount_single(fs_type, flags, data, openprom_fill_super);
+}
+
+static struct file_system_type openprom_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "openpromfs",
+ .mount = openprom_mount,
+ .kill_sb = kill_anon_super,
+};
+MODULE_ALIAS_FS("openpromfs");
+
+static void op_inode_init_once(void *data)
+{
+ struct op_inode_info *oi = (struct op_inode_info *) data;
+
+ inode_init_once(&oi->vfs_inode);
+}
+
+static int __init init_openprom_fs(void)
+{
+ int err;
+
+ op_inode_cachep = kmem_cache_create("op_inode_cache",
+ sizeof(struct op_inode_info),
+ 0,
+ (SLAB_RECLAIM_ACCOUNT |
+ SLAB_MEM_SPREAD),
+ op_inode_init_once);
+ if (!op_inode_cachep)
+ return -ENOMEM;
+
+ err = register_filesystem(&openprom_fs_type);
+ if (err)
+ kmem_cache_destroy(op_inode_cachep);
+
+ return err;
+}
+
+static void __exit exit_openprom_fs(void)
+{
+ unregister_filesystem(&openprom_fs_type);
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(op_inode_cachep);
+}
+
+module_init(init_openprom_fs)
+module_exit(exit_openprom_fs)
+MODULE_LICENSE("GPL");