/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2001 Dag-Erling Coïdan Smørgrav
* All rights reserved.
*
* 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
* in this position and unchanged.
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
* $FreeBSD$
*/
#ifndef _PSEUDOFS_H_INCLUDED
#define _PSEUDOFS_H_INCLUDED
#include <sys/jail.h>
/*
* Opaque structures
*/
struct mntarg;
struct mount;
struct nameidata;
struct proc;
struct sbuf;
struct statfs;
struct thread;
struct uio;
struct vfsconf;
struct vnode;
/*
* Limits and constants
*/
#define PFS_NAMELEN 128
#define PFS_FSNAMELEN 16 /* equal to MFSNAMELEN */
#ifndef __rtems__
#define PFS_DELEN (offsetof(struct dirent, d_name) + PFS_NAMELEN)
#else /* __rtems__ */
#define PFS_DELEN (offsetof(struct dirent, d_name) + PFS_NAMELEN + 2)
#endif /* __rtems__ */
typedef enum {
pfstype_none = 0,
pfstype_root,
pfstype_dir,
pfstype_this,
pfstype_parent,
pfstype_file,
pfstype_symlink,
pfstype_procdir
} pfs_type_t;
/*
* Flags
*/
#define PFS_RD 0x0001 /* readable */
#define PFS_WR 0x0002 /* writeable */
#define PFS_RDWR (PFS_RD|PFS_WR)
#define PFS_RAWRD 0x0004 /* raw reader */
#define PFS_RAWWR 0x0008 /* raw writer */
#define PFS_RAW (PFS_RAWRD|PFS_RAWWR)
#define PFS_PROCDEP 0x0010 /* process-dependent */
#define PFS_NOWAIT 0x0020 /* allow malloc to fail */
/*
* Data structures
*/
struct pfs_info;
struct pfs_node;
/*
* Init / uninit callback
*/
#define PFS_INIT_ARGS \
struct pfs_info *pi, struct vfsconf *vfc
#define PFS_INIT_ARGNAMES \
pi, vfc
#define PFS_INIT_PROTO(name) \
int name(PFS_INIT_ARGS);
typedef int (*pfs_init_t)(PFS_INIT_ARGS);
/*
* Filler callback
* Called with proc held but unlocked
*/
#define PFS_FILL_ARGS \
struct thread *td, struct proc *p, struct pfs_node *pn, \
struct sbuf *sb, struct uio *uio
#define PFS_FILL_ARGNAMES \
td, p, pn, sb, uio
#define PFS_FILL_PROTO(name) \
int name(PFS_FILL_ARGS);
typedef int (*pfs_fill_t)(PFS_FILL_ARGS);
/*
* Attribute callback
* Called with proc locked
*/
struct vattr;
#define PFS_ATTR_ARGS \
struct thread *td, struct proc *p, struct pfs_node *pn, \
struct vattr *vap
#define PFS_ATTR_ARGNAMES \
td, p, pn, vap
#define PFS_ATTR_PROTO(name) \
int name(PFS_ATTR_ARGS);
typedef int (*pfs_attr_t)(PFS_ATTR_ARGS);
/*
* Visibility callback
* Called with proc locked
*/
#define PFS_VIS_ARGS \
struct thread *td, struct proc *p, struct pfs_node *pn
#define PFS_VIS_ARGNAMES \
td, p, pn
#define PFS_VIS_PROTO(name) \
int name(PFS_VIS_ARGS);
typedef int (*pfs_vis_t)(PFS_VIS_ARGS);
/*
* Ioctl callback
* Called with proc locked
*/
#define PFS_IOCTL_ARGS \
struct thread *td, struct proc *p, struct pfs_node *pn, \
unsigned long cmd, void *data
#define PFS_IOCTL_ARGNAMES \
td, p, pn, cmd, data
#define PFS_IOCTL_PROTO(name) \
int name(PFS_IOCTL_ARGS);
typedef int (*pfs_ioctl_t)(PFS_IOCTL_ARGS);
/*
* Getextattr callback
* Called with proc locked
*/
#define PFS_GETEXTATTR_ARGS \
struct thread *td, struct proc *p, struct pfs_node *pn, \
int attrnamespace, const char *name, struct uio *uio, \
size_t *size, struct ucred *cred
#define PFS_GETEXTATTR_ARGNAMES \
td, p, pn, attrnamespace, name, uio, size, cred
#define PFS_GETEXTATTR_PROTO(name) \
int name(PFS_GETEXTATTR_ARGS);
struct ucred;
typedef int (*pfs_getextattr_t)(PFS_GETEXTATTR_ARGS);
/*
* Last-close callback
* Called with proc locked
*/
#define PFS_CLOSE_ARGS \
struct thread *td, struct proc *p, struct pfs_node *pn
#define PFS_CLOSE_ARGNAMES \
td, p, pn
#define PFS_CLOSE_PROTO(name) \
int name(PFS_CLOSE_ARGS);
typedef int (*pfs_close_t)(PFS_CLOSE_ARGS);
/*
* Destroy callback
*/
#define PFS_DESTROY_ARGS \
struct pfs_node *pn
#define PFS_DESTROY_ARGNAMES \
pn
#define PFS_DESTROY_PROTO(name) \
int name(PFS_DESTROY_ARGS);
typedef int (*pfs_destroy_t)(PFS_DESTROY_ARGS);
/*
* pfs_info: describes a pseudofs instance
*
* The pi_mutex is only used to avoid using the global subr_unit lock
* for unrhdr. The rest of struct pfs_info is only modified during
* vfs_init() and vfs_uninit() of the consumer filesystem.
*/
struct pfs_info {
char pi_name[PFS_FSNAMELEN];
pfs_init_t pi_init;
pfs_init_t pi_uninit;
/* members below this line are initialized at run time */
struct pfs_node *pi_root;
struct mtx pi_mutex;
struct unrhdr *pi_unrhdr;
};
/*
* pfs_node: describes a node (file or directory) within a pseudofs
*
* - Fields marked (o) are protected by the node's own mutex.
* - Fields marked (p) are protected by the node's parent's mutex.
* - Remaining fields are not protected by any lock and are assumed to be
* immutable once the node has been created.
*
* To prevent deadlocks, if a node's mutex is to be held at the same time
* as its parent's (e.g. when adding or removing nodes to a directory),
* the parent's mutex must always be acquired first. Unfortunately, this
* is not enforcable by WITNESS.
*/
struct pfs_node {
char pn_name[PFS_NAMELEN];
pfs_type_t pn_type;
int pn_flags;
struct mtx pn_mutex;
void *pn_data; /* (o) */
pfs_fill_t pn_fill;
pfs_ioctl_t pn_ioctl;
pfs_close_t pn_close;
pfs_attr_t pn_attr;
pfs_vis_t pn_vis;
pfs_getextattr_t pn_getextattr;
pfs_destroy_t pn_destroy;
struct pfs_info *pn_info;
u_int32_t pn_fileno; /* (o) */
struct pfs_node *pn_parent; /* (o) */
struct pfs_node *pn_nodes; /* (o) */
struct pfs_node *pn_next; /* (p) */
};
/*
* VFS interface
*/
int pfs_mount (struct pfs_info *pi, struct mount *mp);
int pfs_cmount (struct mntarg *ma, void *data, uint64_t flags);
int pfs_unmount (struct mount *mp, int mntflags);
int pfs_root (struct mount *mp, int flags,
struct vnode **vpp);
int pfs_statfs (struct mount *mp, struct statfs *sbp);
int pfs_init (struct pfs_info *pi, struct vfsconf *vfc);
int pfs_uninit (struct pfs_info *pi, struct vfsconf *vfc);
/*
* Directory structure construction and manipulation
*/
struct pfs_node *pfs_create_dir (struct pfs_node *parent, const char *name,
pfs_attr_t attr, pfs_vis_t vis,
pfs_destroy_t destroy, int flags);
struct pfs_node *pfs_create_file(struct pfs_node *parent, const char *name,
pfs_fill_t fill, pfs_attr_t attr,
pfs_vis_t vis, pfs_destroy_t destroy,
int flags);
struct pfs_node *pfs_create_link(struct pfs_node *parent, const char *name,
pfs_fill_t fill, pfs_attr_t attr,
pfs_vis_t vis, pfs_destroy_t destroy,
int flags);
struct pfs_node *pfs_find_node (struct pfs_node *parent, const char *name);
void pfs_purge (struct pfs_node *pn);
int pfs_destroy (struct pfs_node *pn);
/*
* Now for some initialization magic...
*/
#define PSEUDOFS(name, version, flags) \
\
static struct pfs_info name##_info = { \
#name, \
name##_init, \
name##_uninit, \
}; \
\
static int \
_##name##_mount(struct mount *mp) { \
return (pfs_mount(&name##_info, mp)); \
} \
\
static int \
_##name##_init(struct vfsconf *vfc) { \
return (pfs_init(&name##_info, vfc)); \
} \
\
static int \
_##name##_uninit(struct vfsconf *vfc) { \
return (pfs_uninit(&name##_info, vfc)); \
} \
\
static struct vfsops name##_vfsops = { \
.vfs_cmount = pfs_cmount, \
.vfs_init = _##name##_init, \
.vfs_mount = _##name##_mount, \
.vfs_root = pfs_root, \
.vfs_statfs = pfs_statfs, \
.vfs_uninit = _##name##_uninit, \
.vfs_unmount = pfs_unmount, \
}; \
VFS_SET(name##_vfsops, name, VFCF_SYNTHETIC | flags); \
MODULE_VERSION(name, version); \
MODULE_DEPEND(name, pseudofs, 1, 1, 1);
#endif
