diff options
Diffstat (limited to 'fs/openpromfs/inode.c')
| -rw-r--r-- | fs/openpromfs/inode.c | 471 |
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"); |