/*
 * Copyright (c) 2009 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Alex Hornung <ahornung@gmail.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name of The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
#ifndef _SYS_DEVFS_H_
#define _SYS_DEVFS_H_

#if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)

#ifndef _SYS_TYPES_H_
#include <sys/types.h>
#endif
#ifndef _SYS_QUEUE_H_
#include <sys/queue.h>
#endif
#ifdef _KERNEL
#ifndef _SYS_LOCK_H_
#include <sys/lock.h>
#endif
#ifndef _SYS_CONF_H_
#include <sys/conf.h>
#endif
#ifndef _SYS_MSGPORT_H_
#include <sys/msgport.h>
#endif
#endif  /* _KERNEL */
#ifndef _SYS_DIRENT_H_
#include <sys/dirent.h>
#endif
#ifndef _SYS_DEVICE_H_
#include <sys/device.h>
#endif
#ifdef _KERNEL
#ifndef _SYS_UCRED_H_
#include <sys/ucred.h>
#endif
#endif  /* _KERNEL */


typedef enum {
        Nroot,          /* the filesystem root */
        Nlink,
        Nreg,
        Ndir,
        Ndev
} devfs_nodetype;

struct devfs_dirent {
        ino_t           d_ino;          /* file number of entry */
        uint16_t        d_namlen;       /* strlen(d_name) */
        uint8_t         d_type;         /* file type */
        char            *d_name;
};

struct devfs_fid {
        uint16_t        fid_len;        /* Length of structure. */
        uint16_t        fid_pad;        /* Force 32-bit alignment. */
        uint32_t        fid_gen;
        ino_t           fid_ino;        /* File number (ino). */
};

struct devfs_node {
        cdev_t          d_dev;          /* device associated with this node */

        struct mount    *mp;            /* mount point of this node */
        struct devfs_dirent d_dir;      /* dirent data (name, inode, ...) */
        struct vnode    *v_node;        /* associated vnode */
        struct devfs_node *parent;      /* parent of this node */
        devfs_nodetype  node_type;      /* devfs node type */

        u_int64_t       refs;           /* currently unused */
        size_t          nchildren;      /* number of children of a parent */
        u_int64_t       cookie_jar;     /* cookie pool for children */
        u_int64_t       cookie;         /* directory entry cookie for readdir */

        struct devfs_node *link_target; /* target of this autolink-type node */
        size_t          nlinks;         /* hard links */

        char            *symlink_name;  /* symlink name for readlink */
        size_t          symlink_namelen; /* symlink name length for readlink */

        u_short         mode;           /* files access mode and type */
        uid_t           uid;            /* owner user id */
        gid_t           gid;            /* owner group id */
        u_long          flags;

        struct timespec atime;          /* time of last access */
        struct timespec mtime;          /* time of last modification */
        struct timespec ctime;          /* time file changed */

        TAILQ_ENTRY(devfs_node) link;
        TAILQ_HEAD(, devfs_node) list;  /* linked list of children */
};

#ifdef _KERNEL
struct devfs_orphan {
        struct devfs_node *node;
        TAILQ_ENTRY(devfs_orphan) link;
};

struct devfs_mnt_data {
        TAILQ_HEAD(, devfs_orphan) orphan_list;
        TAILQ_ENTRY(devfs_mnt_data) link;

        struct devfs_node *root_node;
        struct mount    *mp;
        uint32_t        mnt_type;
        long            leak_count;
        long            file_count;
        int             jailed;
        size_t          mntonnamelen;
};

struct devfs_clone_handler {
        char            *name;
        u_char          namlen;
        d_clone_t       *nhandler;
        TAILQ_ENTRY(devfs_clone_handler) link;
};


struct devfs_alias {
        char            *name;
        size_t          namlen;
        cdev_t          dev_target;
        TAILQ_ENTRY(devfs_alias) link;
};

struct devfs_dev_ops {
        struct dev_ops *ops;
        int     ref_count;
        int id;
        TAILQ_ENTRY(devfs_dev_ops) link;
};

typedef struct devfs_msg {
        struct lwkt_msg hdr;

        union {
                struct {
                        cdev_t  dev;
                        uid_t   uid;
                        gid_t   gid;
                        int     perms;
                } __m_dev;
                struct {
                        struct devfs_mnt_data *mnt;
                } __m_mnt;
                struct {
                        const char      *name;
                        d_clone_t       *nhandler;
                } __m_chandler;
                struct {
                        void *load;
                        void *load2;
                } __m_gen;
                struct {
                        void *resp;
                } __m_resp;
                struct {
                        dev_t   udev;
                } __m_udev;
                struct {
                        cdev_t  cdev;
                } __m_cdev;
                struct {
                        char    *name;
                } __m_name;
                struct {
                        char    *basename;
                        u_char  unit;
                        struct vnode *vp;
                } __m_clone;
                struct {
                        struct devfs_node *node;
                } __m_node;
                struct {
                        char    *name;
                        char    *target;
                        struct mount *mp;
                } __m_link;
                struct {
                        struct dev_ops *ops;
                        int     minor;
                } __m_ops;
                struct {
                        cdev_t          dev;
                        uint32_t        flag;
                } __m_flags;
                struct {
                        ino_t   ino;
                        struct vnode *vp;
                        struct mount *mp;
                } __m_ino;
        } __m_u;
} *devfs_msg_t;

#define mdv_chandler    __m_u.__m_chandler
#define mdv_mnt         __m_u.__m_mnt.mnt
#define mdv_load        __m_u.__m_gen.load
#define mdv_load2       __m_u.__m_gen.load2
#define mdv_response    __m_u.__m_resp.resp
#define mdv_dev         __m_u.__m_dev
#define mdv_link        __m_u.__m_link
#define mdv_udev        __m_u.__m_udev.udev
#define mdv_cdev        __m_u.__m_cdev.cdev
#define mdv_name        __m_u.__m_name.name
#define mdv_clone       __m_u.__m_clone
#define mdv_node        __m_u.__m_node.node
#define mdv_ops         __m_u.__m_ops
#define mdv_flags       __m_u.__m_flags
#define mdv_ino         __m_u.__m_ino


typedef struct devfs_core_args {
        thread_t     td;
} *devfs_core_args_t;

TAILQ_HEAD(devfs_node_head, devfs_node);
TAILQ_HEAD(devfs_dev_head, cdev);
TAILQ_HEAD(devfs_mnt_head, devfs_mnt_data);
TAILQ_HEAD(devfs_chandler_head, devfs_clone_handler);
TAILQ_HEAD(devfs_alias_head, devfs_alias);
TAILQ_HEAD(devfs_dev_ops_head, devfs_dev_ops);

typedef void (devfs_scan_t)(char *, cdev_t, bool, void *);
typedef void* (devfs_iterate_callback_t)(struct devfs_node *, void *);

#define DEVFS_NODE(x)           ((struct devfs_node *)((x)->v_data))
#define DEVFS_MNTDATA(x)        ((struct devfs_mnt_data *)((x)->mnt_data))
#define DEVFS_ORPHANLIST(x)     (&(DEVFS_MNTDATA(x)->orphan_list))
#define DEVFS_DENODE_HEAD(x)    (&((x)->list))
#if 0
#define DEVFS_ISDIGIT(x)        ((x >= '0') && (x <= '9'))
#endif

/*
 * -rwxr-xr-x
 */
#define DEVFS_DEFAULT_MODE      ((VREAD|VWRITE|VEXEC) | ((VREAD|VEXEC)>>3) | \
                                 ((VREAD|VEXEC)>>6));

#define DEVFS_DEFAULT_UID       0       /* root */
#define DEVFS_DEFAULT_GID       0       /* wheel */

/*
 * debug levels
 */
#define DEVFS_DEBUG_SHOW        0x00
#define DEVFS_DEBUG_WARNING     0x01
#define DEVFS_DEBUG_INFO        0x02
#define DEVFS_DEBUG_DEBUG       0x03

/*
 * Message ids
 */
#define DEVFS_TERMINATE_CORE            0x01
#define DEVFS_DEVICE_CREATE             0x02
#define DEVFS_DEVICE_DESTROY            0x03
#define DEVFS_MOUNT_ADD                 0x04
#define DEVFS_MOUNT_DEL                 0x05
#define DEVFS_CREATE_ALL_DEV            0x06
#define DEVFS_DESTROY_RELATED           0x07
#define DEVFS_DESTROY_DEV_BY_OPS        0x08
#define DEVFS_CHANDLER_ADD              0x09
#define DEVFS_CHANDLER_DEL              0x0A
#define DEVFS_FIND_DEVICE_BY_DEVID      0x0B
#define DEVFS_FIND_DEVICE_BY_NAME       0x0C
#define DEVFS_MAKE_ALIAS                0x0D
#define DEVFS_DESTROY_ALIAS             0x0E
#define DEVFS_APPLY_RULES               0x0F
#define DEVFS_RESET_RULES               0x10
#define DEVFS_SCAN_CALLBACK             0x11
#define DEVFS_CLR_RELATED_FLAG          0x12
#define DEVFS_DESTROY_RELATED_WO_FLAG   0x13
#define DEVFS_INODE_TO_VNODE            0x14
#define DEVFS_SYNC                      0x99

/*
 * Node flags
 *
 * HIDDEN       Makes node inaccessible, apart from already allocated vnodes
 * INVISIBLE    Makes node invisible in a readdir()
 */
#define DEVFS_NODE_LINKED               0x001   /* Linked into topology */
#define DEVFS_USER_CREATED              0x002   /* Node was user-created */
#define DEVFS_ORPHANED                  0x004   /* on orphan list */
#define DEVFS_CLONED                    0x008   /* Created by cloning code */
#define DEVFS_HIDDEN                    0x010   /* Makes node inaccessible */
#define DEVFS_INVISIBLE                 0x020   /* Makes node invisible */
#define DEVFS_PTY                       0x040   /* PTY device */
#define DEVFS_DESTROYED                 0x080   /* Destroy attempt */
#define DEVFS_RULE_CREATED              0x100   /* Node was rule-created */
#define DEVFS_RULE_HIDDEN               0x200   /* Node was hidden by a rule */
#define DEVFS_NLINKSWAIT                0x400   /* NLinks final */

/*
 * Clone helper stuff
 */
#define DEVFS_BITMAP_INITIAL_SIZE       1
#define DEVFS_CLONE_BITMAP(name)        devfs_ ## name ## _clone_bitmap
#define DEVFS_DEFINE_CLONE_BITMAP(name) \
                        struct devfs_bitmap DEVFS_CLONE_BITMAP(name)
#define DEVFS_DECLARE_CLONE_BITMAP(name) \
                        extern struct devfs_bitmap DEVFS_CLONE_BITMAP(name)

struct devfs_bitmap {
        int             chunks;
        unsigned long   *bitmap;
};
#endif /* _KERNEL */

#if 0
struct devfs_unit_hash {
        struct devfs_unit_hash *next;
        int             unit_no;
        cdev_t          dev;
};
#endif

#ifdef _KERNEL
void devfs_clone_bitmap_init(struct devfs_bitmap *);
void devfs_clone_bitmap_uninit(struct devfs_bitmap *);
int devfs_clone_bitmap_set(struct devfs_bitmap *, int);
int devfs_clone_bitmap_get(struct devfs_bitmap *, int);
int devfs_clone_bitmap_chk(struct devfs_bitmap *, int);
void devfs_clone_bitmap_put(struct devfs_bitmap *, int);

/*
 * Prototypes
 */
int devfs_debug(int level, char *fmt, ...) __printflike(2, 3);
int devfs_allocv(struct vnode **, struct devfs_node *);
struct devfs_node *devfs_allocp(devfs_nodetype, char *, struct devfs_node *,
                                struct mount *, cdev_t);
int devfs_allocvp(struct mount *, struct vnode **, devfs_nodetype, char *,
                                struct devfs_node *, cdev_t);

void devfs_freep(struct devfs_node *);
void devfs_unlinkp(struct devfs_node *);

void devfs_tracer_add_orphan(struct devfs_node *);
void devfs_tracer_del_orphan(struct devfs_node *);
size_t devfs_tracer_orphan_count(struct mount *, int);

int devfs_set_perms(struct devfs_node *, uid_t, gid_t, u_short, u_long);
int devfs_gc(struct devfs_node *);

int devfs_create_dev(cdev_t, uid_t, gid_t, int);
int devfs_destroy_dev(cdev_t);

int  devfs_msg_send_sync(uint32_t, devfs_msg_t);
void devfs_msg_send(uint32_t, devfs_msg_t);
void devfs_msg_send_dev(uint32_t, cdev_t dev, uid_t, gid_t, int);
void devfs_msg_send_mount(uint32_t, struct devfs_mnt_data *);
void devfs_msg_send_ops(uint32_t, struct dev_ops *, int);
void devfs_msg_send_chandler(uint32_t, char *, d_clone_t);
void devfs_msg_send_generic(uint32_t, void *);
void devfs_msg_send_name(uint32_t, char *);
void devfs_msg_send_link(uint32_t, char *, char *, struct mount *);

devfs_msg_t devfs_msg_get(void);
int devfs_msg_put(devfs_msg_t);

int devfs_mount_add(struct devfs_mnt_data *);
int devfs_mount_del(struct devfs_mnt_data *);

int devfs_create_all_dev(struct devfs_node *);

struct devfs_node *devfs_resolve_or_create_path(
                                struct devfs_node *, char *, int);
int devfs_resolve_name_path(char *, char *, char **, char **);
struct devfs_node *devfs_create_device_node(struct devfs_node *, cdev_t, int *,
                      char *, char *, ...) __printf0like(5, 6);

int devfs_destroy_device_node(struct devfs_node *, cdev_t);
int devfs_destroy_node(struct devfs_node *, char *);
int devfs_destroy_related(cdev_t);
int devfs_destroy_dev_by_ops(struct dev_ops *, int);
struct devfs_node *devfs_find_device_node_by_name(struct devfs_node *, char *);

cdev_t devfs_new_cdev(struct dev_ops *, int, struct dev_ops *);
void devfs_assume_knotes(cdev_t dev, struct kqinfo *kqi);

cdev_t devfs_find_device_by_name(const char *, ...) __printf0like(1, 2);
cdev_t devfs_find_device_by_devid(dev_t);

struct vnode *devfs_inode_to_vnode(struct mount *, ino_t);

int devfs_clone_handler_add(const char *, d_clone_t *);
int devfs_clone_handler_del(const char *);
cdev_t devfs_clone(cdev_t, const char *, size_t, int, struct ucred *);

int devfs_link_dev(cdev_t);

int devfs_make_alias(const char *, cdev_t);
int devfs_destroy_alias(const char *, cdev_t);

int devfs_alias_create(char *, struct devfs_node *, int);

int devfs_apply_rules(char *);
int devfs_reset_rules(char *);

int devfs_scan_callback(devfs_scan_t *, void *);

int devfs_clr_related_flag(cdev_t, uint32_t);
int devfs_destroy_related_without_flag(cdev_t, uint32_t);
int devfs_node_is_accessible(struct devfs_node *);

void devfs_config(void);

void *devfs_iterate_topology(struct devfs_node *node,
                devfs_iterate_callback_t *callback, void *arg1);

void *devfs_find_device_node_callback(struct devfs_node *, cdev_t);

typedef void d_priv_dtor_t(void *data);
int devfs_get_cdevpriv(struct file *fp, void **datap);
int devfs_set_cdevpriv(struct file *fp, void *priv, d_priv_dtor_t *dtr);
void devfs_clear_cdevpriv(struct file *fp);

int devfs_WildCmp(const char *w, const char *s);
int devfs_WildCaseCmp(const char *w, const char *s);
#endif  /* _KERNEL */

#endif /* KERNEL || _KERNEL_STRUCTURES */

#define DEVFS_MNT_RULESET       0x01
#define DEVFS_MNT_JAIL          0x02

struct devfs_mount_info {
        int flags;
};

#endif /* _SYS_DEVFS_H_ */