rc.conf: Add and document the missing root_rw_mount=YES

[dragonfly.git] / sys / sys / device.h

/*
 * Copyright (c) 2003,2004,2007 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.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_DEVICE_H_
#define _SYS_DEVICE_H_

#ifdef _KERNEL
#ifndef _SYS_TYPES_H_
#include <sys/types.h>
#endif
#ifndef _SYS_TREE_H_
#include <sys/tree.h>
#endif
#ifndef _SYS_SYSLINK_RPC_H_
#include <sys/syslink_rpc.h>
#endif

struct cdev;
struct ucred;
struct devfs_bitmap;
struct vm_page;
struct vm_map_backing;
struct vnode;

/*
 * This structure is at the base of every device args structure
 */
struct dev_generic_args {
        struct syslink_desc *a_desc;
        struct cdev *a_dev;
};

typedef struct dev_generic_args dev_default_args;

/*
 * int d_open(cdev_t dev, int oflags, int devtype, struct ucred *cred)
 */
struct dev_open_args {
        struct dev_generic_args a_head;
        int             a_oflags;
        int             a_devtype;
        struct ucred    *a_cred;
        struct file     **a_fpp;
};

/*
 * int d_close(cdev_t dev, int fflag, int devtype)
 */
struct dev_close_args {
        struct dev_generic_args a_head;
        int             a_fflag;
        int             a_devtype;
        struct file     *a_fp;
};

/*
 * int d_read(cdev_t dev, struct uio *uio, int ioflag)
 */
struct dev_read_args {
        struct dev_generic_args a_head;
        struct uio      *a_uio;
        int             a_ioflag;
        struct file     *a_fp;
};

/*
 * int d_write(cdev_t dev, struct uio *uio, int ioflag)
 */
struct dev_write_args {
        struct dev_generic_args a_head;
        struct uio      *a_uio;
        int             a_ioflag;
        struct file     *a_fp;
};

/*
 * int d_ioctl(cdev_t dev, u_long cmd, caddr_t data, int fflag,
 *             struct ucred *cred, struct sysmsg *msg)
 */
struct dev_ioctl_args {
        struct dev_generic_args a_head;
        u_long          a_cmd;
        caddr_t         a_data;
        int             a_fflag;
        struct ucred    *a_cred;
        struct sysmsg   *a_sysmsg;
        struct file     *a_fp;
};

/*
 * int d_mmap(cdev_t dev, vm_offset_t offset, int nprot)
 */
struct dev_mmap_args {
        struct dev_generic_args a_head;
        vm_offset_t     a_offset;
        int             a_nprot;
        int64_t         a_result;       /* page number */
        struct file     *a_fp;
};

/*
 * int d_mmap_single(cdev_t dev, vm_ooffset_t *offset, vm_size_t size,
 *                   struct vm_object **object, int nprot)
 */
struct dev_mmap_single_args {
        struct dev_generic_args a_head;
        vm_ooffset_t    *a_offset;
        vm_size_t               a_size;
        struct vm_object **a_object;
        int             a_nprot;
        struct file     *a_fp;
};

/*
 * void d_strategy(cdev_t dev, struct bio *bio)
 */
struct dev_strategy_args {
        struct dev_generic_args a_head;
        struct bio      *a_bio;
};

/*
 * void d_dump(cdev_t dev, void *virtual, vm_offset_t physical,
                off_t offset, size_t length)
 */
struct dev_dump_args {
        struct dev_generic_args a_head;
        u_int64_t       a_count;
        u_int64_t       a_blkno;
        u_int           a_secsize;
        void            *a_virtual;
        vm_offset_t     a_physical;
        off_t           a_offset;
        size_t          a_length;
};

/*
 * int d_psize(cdev_t dev)
 */
struct dev_psize_args {
        struct dev_generic_args a_head;
        int64_t         a_result;
};

/*
 * int d_kqfilter(cdev_t dev, struct knote *kn)
 */
struct dev_kqfilter_args {
        struct dev_generic_args a_head;
        struct knote    *a_kn;
        int             a_result;
        struct file     *a_fp;
};

/*
 * int d_clone(cdev_t dev);
 */
struct dev_clone_args {
        struct dev_generic_args a_head;

        struct cdev     *a_dev;
        const char      *a_name;
        size_t          a_namelen;
        struct ucred    *a_cred;
        int             a_mode;
};

/*
 * int d_revoke(cdev_t dev)
 */
struct dev_revoke_args {
        struct dev_generic_args a_head;
};

/*
 * Typedefs to help drivers declare the driver routines and such
 */
typedef int d_default_t (struct dev_generic_args *ap);
typedef int d_open_t (struct dev_open_args *ap);
typedef int d_close_t (struct dev_close_args *ap);
typedef int d_read_t (struct dev_read_args *ap);
typedef int d_write_t (struct dev_write_args *ap);
typedef int d_ioctl_t (struct dev_ioctl_args *ap);
typedef int d_mmap_t (struct dev_mmap_args *ap);
typedef int d_mmap_single_t (struct dev_mmap_single_args *ap);
typedef int d_strategy_t (struct dev_strategy_args *ap);
typedef int d_dump_t (struct dev_dump_args *ap);
typedef int d_psize_t (struct dev_psize_args *ap);
typedef int d_kqfilter_t (struct dev_kqfilter_args *ap);
typedef int d_clone_t (struct dev_clone_args *ap);
typedef int d_revoke_t (struct dev_revoke_args *ap);

/*
 * Character device switch table.
 *
 * NOTE: positions are hard coded for static structure initialization.
 */
struct dev_ops {
        struct {
                const char      *name;  /* base name, e.g. 'da' */
                int              maj;   /* major device number */
                u_int            flags; /* D_XXX flags */
                void            *data;  /* custom driver data */
                int              refs;  /* ref count */
                int              id;
        } head;

#define dev_ops_first_field     d_default
        d_default_t     *d_default;
        d_open_t        *d_open;
        d_close_t       *d_close;
        d_read_t        *d_read;
        d_write_t       *d_write;
        d_ioctl_t       *d_ioctl;
        d_mmap_t        *d_mmap;
        d_mmap_single_t *d_mmap_single;
        d_strategy_t    *d_strategy;
        d_dump_t        *d_dump;
        d_psize_t       *d_psize;
        d_kqfilter_t    *d_kqfilter;
        d_clone_t       *d_clone;       /* clone from base dev_ops */
        d_revoke_t      *d_revoke;
        int (*d_uksmap)(struct vm_map_backing *ba, int op,
                                struct cdev *dev, struct vm_page *fake);
#define dev_ops_last_field      d_uksmap
};
#endif /* _KERNEL */

/*
 * Types for d_flags.
 */
#define D_TAPE          0x0001
#define D_DISK          0x0002
#define D_TTY           0x0004
#define D_MEM           0x0008

#define D_TYPEMASK      0xffff
#define D_SEEKABLE      (D_TAPE | D_DISK | D_MEM)

/*
 * Flags for d_flags.
 *
 * D_NOEMERGPGR         Indicates complex layering, the emergency pager
 *                      should skip buffers related to such devices.
 */
#ifdef _KERNEL
#define D_MEMDISK       0x00010000      /* memory type disk */
#define D_UNUSED17      0x00020000      /* was: nagged about missing make_dev() */
#define D_CANFREE       0x00040000      /* can free blocks */
#define D_TRACKCLOSE    0x00080000      /* track all closes */
#define D_MASTER        0x00100000      /* used by pty/tty code */
#define D_NOEMERGPGR    0x00200000      /* too complex for emergency pager */
#define D_MPSAFE        0x00400000      /* all dev_d*() calls are MPSAFE */
#define D_KVABIO        0x00800000      /* device support KVABIO API */
#define D_QUICK         0x01000000      /* no fancy open/close support needed*/
#endif

/*
 * A union of all possible argument structures.
 */
#if 0
union dev_args_union {
        struct dev_generic_args du_head;
        struct dev_open_args    du_open;
        struct dev_close_args   du_close;
        struct dev_read_args    du_read;
        struct dev_write_args   du_write;
        struct dev_ioctl_args   du_ioctl;
        struct dev_mmap_args    du_mmap;
        struct dev_strategy_args du_strategy;
        struct dev_dump_args    du_dump;
        struct dev_psize_args   du_psize;
        struct dev_kqfilter_args du_kqfilter;
        struct dev_clone_args   du_clone;
};
#endif

#ifdef _KERNEL
/*
 * Linking structure for mask/match registration
 */
struct dev_ops_link {
        struct dev_ops_link *next;
        u_int           mask;
        u_int           match;
        struct dev_ops  *ops;
};

struct dev_ops_maj {
        RB_ENTRY(dev_ops_maj) rbnode; /* red-black tree of major nums */
        struct dev_ops_link *link;
        int             maj;
};

RB_HEAD(dev_ops_rb_tree, dev_ops_maj);
RB_PROTOTYPE2(dev_ops_rb_tree, dev_ops_maj, rbnode, rb_dev_ops_compare, int);
#endif /* _KERNEL */

#ifdef _KERNEL

extern struct dev_ops dead_dev_ops;

struct disk;
struct sysmsg;

int dev_dopen(cdev_t dev, int oflags, int devtype, struct ucred *cred,
    struct file **fpp, struct vnode *vp);
int dev_dclose(cdev_t dev, int fflag, int devtype, struct file *fp);
void dev_dstrategy(cdev_t dev, struct bio *bio);
void dev_dstrategy_chain(cdev_t dev, struct bio *bio);
int dev_dioctl(cdev_t dev, u_long cmd, caddr_t data,
                int fflag, struct ucred *cred, struct sysmsg *msg, struct file *fp);
int dev_ddump(cdev_t dev, void *virtual, vm_offset_t physical, off_t offset,
    size_t length);
int64_t dev_dpsize(cdev_t dev);
int dev_dread(cdev_t dev, struct uio *uio, int ioflag, struct file *fp);
int dev_dwrite(cdev_t dev, struct uio *uio, int ioflag, struct file *fp);
int dev_dkqfilter(cdev_t dev, struct knote *kn, struct file *fp);
int64_t dev_dmmap(cdev_t dev, vm_offset_t offset, int nprot, struct file *fp);
int dev_dmmap_single(cdev_t dev, vm_ooffset_t *offset, vm_size_t size,
                        struct vm_object **object, int nprot, struct file *fp);
int dev_dclone(cdev_t dev);
int dev_drevoke(cdev_t dev);

int dev_drefs(cdev_t dev);
const char *dev_dname(cdev_t dev);
int dev_dmaj(cdev_t dev);
int dev_dflags(cdev_t dev);
int dev_doperate(struct dev_generic_args *ap);
int dev_doperate_ops(struct dev_ops *, struct dev_generic_args *ap);

d_open_t        nullopen;
d_close_t       nullclose;

extern struct syslink_desc dev_default_desc;
extern struct syslink_desc dev_open_desc;
extern struct syslink_desc dev_close_desc;
extern struct syslink_desc dev_read_desc;
extern struct syslink_desc dev_write_desc;
extern struct syslink_desc dev_ioctl_desc;
extern struct syslink_desc dev_dump_desc;
extern struct syslink_desc dev_psize_desc;
extern struct syslink_desc dev_mmap_desc;
extern struct syslink_desc dev_mmap_single_desc;
extern struct syslink_desc dev_strategy_desc;
extern struct syslink_desc dev_kqfilter_desc;
extern struct syslink_desc dev_clone_desc;

void compile_dev_ops(struct dev_ops *);
int dev_ops_remove_all(struct dev_ops *ops);
int dev_ops_remove_minor(struct dev_ops *ops, int minor);
struct dev_ops *dev_ops_intercept(cdev_t, struct dev_ops *);
void dev_ops_restore(cdev_t, struct dev_ops *);

#define MAKEDEV_MINNBUF 14
char  *makedev_unit_b32(char *nbuf, uintmax_t num);
cdev_t make_dev(struct dev_ops *ops, int minor, uid_t uid, gid_t gid,
                int perms, const char *fmt, ...) __printflike(6, 7);
cdev_t make_dev_covering(struct dev_ops *ops,  struct dev_ops *bops, int minor,
            uid_t uid, gid_t gid, int perms, const char *fmt, ...) __printflike(7, 8);
cdev_t make_only_dev(struct dev_ops *ops, int minor, uid_t uid, gid_t gid,
                int perms, const char *fmt, ...) __printflike(6, 7);
cdev_t make_only_dev_covering(struct dev_ops *ops, struct dev_ops *bops, int minor,
    uid_t uid, gid_t gid, int perms, const char *fmt, ...) __printflike(7,8);
cdev_t make_only_devfs_dev(struct dev_ops *ops, int minor, uid_t uid, gid_t gid,
           int perms, const char *fmt, ...) __printflike(6, 7);
void destroy_only_dev(cdev_t dev);
int make_dev_alias(cdev_t target, const char *fmt, ...) __printflike(2, 3);
int destroy_dev_alias(cdev_t target, const char *fmt, ...) __printflike(2, 3);
cdev_t make_autoclone_dev(struct dev_ops *ops, struct devfs_bitmap *bitmap,
           d_clone_t *nhandler, uid_t uid, gid_t gid, int perms,
           const char *fmt, ...) __printflike(7, 8);
void destroy_autoclone_dev(cdev_t dev, struct devfs_bitmap *bitmap);
void sync_devs(void);

#endif

#endif