freebsd-dev/sys/sys/file.h
Poul-Henning Kamp e4643c730a "nfiles" is a bad name for a global variable. Call it "openfiles" instead
as this is more correct and matches the sysctl variable.
2004-12-01 09:22:26 +00:00

304 lines
8.5 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. 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.
* 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.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)file.h 8.3 (Berkeley) 1/9/95
* $FreeBSD$
*/
#ifndef _SYS_FILE_H_
#define _SYS_FILE_H_
#ifndef _KERNEL
#include <sys/types.h> /* XXX */
#include <sys/fcntl.h>
#include <sys/unistd.h>
#else
#include <sys/queue.h>
#include <sys/_lock.h>
#include <sys/_mutex.h>
struct stat;
struct thread;
struct uio;
struct knote;
struct vnode;
struct socket;
#endif /* _KERNEL */
#define DTYPE_VNODE 1 /* file */
#define DTYPE_SOCKET 2 /* communications endpoint */
#define DTYPE_PIPE 3 /* pipe */
#define DTYPE_FIFO 4 /* fifo (named pipe) */
#define DTYPE_KQUEUE 5 /* event queue */
#define DTYPE_CRYPTO 6 /* crypto */
#ifdef _KERNEL
struct file;
struct ucred;
typedef int fo_rdwr_t(struct file *fp, struct uio *uio,
struct ucred *active_cred, int flags,
struct thread *td);
#define FOF_OFFSET 1 /* Use the offset in uio argument */
typedef int fo_ioctl_t(struct file *fp, u_long com, void *data,
struct ucred *active_cred, struct thread *td);
typedef int fo_poll_t(struct file *fp, int events,
struct ucred *active_cred, struct thread *td);
typedef int fo_kqfilter_t(struct file *fp, struct knote *kn);
typedef int fo_stat_t(struct file *fp, struct stat *sb,
struct ucred *active_cred, struct thread *td);
typedef int fo_close_t(struct file *fp, struct thread *td);
typedef int fo_flags_t;
struct fileops {
fo_rdwr_t *fo_read;
fo_rdwr_t *fo_write;
fo_ioctl_t *fo_ioctl;
fo_poll_t *fo_poll;
fo_kqfilter_t *fo_kqfilter;
fo_stat_t *fo_stat;
fo_close_t *fo_close;
fo_flags_t fo_flags; /* DFLAG_* below */
};
#define DFLAG_PASSABLE 0x01 /* may be passed via unix sockets. */
#define DFLAG_SEEKABLE 0x02 /* seekable / nonsequential */
/*
* Kernel descriptor table.
* One entry for each open kernel vnode and socket.
*
* Below is the list of locks that protects members in struct file.
*
* (fl) filelist_lock
* (f) f_mtx in struct file
* none not locked
*/
struct file {
LIST_ENTRY(file) f_list;/* (fl) list of active files */
short f_type; /* descriptor type */
void *f_data; /* file descriptor specific data */
u_int f_flag; /* see fcntl.h */
struct mtx *f_mtxp; /* mutex to protect data */
struct fileops *f_ops; /* File operations */
struct ucred *f_cred; /* credentials associated with descriptor */
int f_count; /* (f) reference count */
struct vnode *f_vnode; /* NULL or applicable vnode */
/* DFLAG_SEEKABLE specific fields */
off_t f_offset;
/* DTYPE_SOCKET specific fields */
short f_gcflag; /* used by thread doing fd garbage collection */
#define FMARK 0x1 /* mark during gc() */
#define FDEFER 0x2 /* defer for next gc pass */
int f_msgcount; /* (f) references from message queue */
/* DTYPE_VNODE specific fields */
int f_seqcount; /*
* count of sequential accesses -- cleared
* by most seek operations.
*/
off_t f_nextoff; /*
* offset of next expected read or write
*/
};
#endif /* _KERNEL */
/*
* Userland version of struct file, for sysctl
*/
struct xfile {
size_t xf_size; /* size of struct xfile */
pid_t xf_pid; /* owning process */
uid_t xf_uid; /* effective uid of owning process */
int xf_fd; /* descriptor number */
void *xf_file; /* address of struct file */
short xf_type; /* descriptor type */
int xf_count; /* reference count */
int xf_msgcount; /* references from message queue */
off_t xf_offset; /* file offset */
void *xf_data; /* file descriptor specific data */
void *xf_vnode; /* vnode pointer */
u_int xf_flag; /* flags (see fcntl.h) */
};
#ifdef _KERNEL
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_FILE);
#endif
LIST_HEAD(filelist, file);
extern struct filelist filehead; /* (fl) head of list of open files */
extern struct fileops vnops;
extern struct fileops badfileops;
extern struct fileops socketops;
extern int maxfiles; /* kernel limit on number of open files */
extern int maxfilesperproc; /* per process limit on number of open files */
extern int openfiles; /* (fl) actual number of open files */
extern struct sx filelist_lock; /* sx to protect filelist and openfiles */
int fget(struct thread *td, int fd, struct file **fpp);
int fget_read(struct thread *td, int fd, struct file **fpp);
int fget_write(struct thread *td, int fd, struct file **fpp);
int fdrop(struct file *fp, struct thread *td);
int fdrop_locked(struct file *fp, struct thread *td);
/*
* The socket operations are used a couple of places.
* XXX: This is wrong, they should go through the operations vector for
* XXX: sockets instead of going directly for the individual functions. /phk
*/
fo_rdwr_t soo_read;
fo_rdwr_t soo_write;
fo_ioctl_t soo_ioctl;
fo_poll_t soo_poll;
fo_kqfilter_t soo_kqfilter;
fo_stat_t soo_stat;
fo_close_t soo_close;
/* Lock a file. */
#define FILE_LOCK(f) mtx_lock((f)->f_mtxp)
#define FILE_UNLOCK(f) mtx_unlock((f)->f_mtxp)
#define FILE_LOCKED(f) mtx_owned((f)->f_mtxp)
#define FILE_LOCK_ASSERT(f, type) mtx_assert((f)->f_mtxp, (type))
int fgetvp(struct thread *td, int fd, struct vnode **vpp);
int fgetvp_read(struct thread *td, int fd, struct vnode **vpp);
int fgetvp_write(struct thread *td, int fd, struct vnode **vpp);
int fgetsock(struct thread *td, int fd, struct socket **spp, u_int *fflagp);
void fputsock(struct socket *sp);
#define fhold_locked(fp) \
do { \
FILE_LOCK_ASSERT(fp, MA_OWNED); \
(fp)->f_count++; \
} while (0)
#define fhold(fp) \
do { \
FILE_LOCK(fp); \
(fp)->f_count++; \
FILE_UNLOCK(fp); \
} while (0)
static __inline fo_rdwr_t fo_read;
static __inline fo_rdwr_t fo_write;
static __inline fo_ioctl_t fo_ioctl;
static __inline fo_poll_t fo_poll;
static __inline fo_kqfilter_t fo_kqfilter;
static __inline fo_stat_t fo_stat;
static __inline fo_close_t fo_close;
static __inline int
fo_read(fp, uio, active_cred, flags, td)
struct file *fp;
struct uio *uio;
struct ucred *active_cred;
int flags;
struct thread *td;
{
return ((*fp->f_ops->fo_read)(fp, uio, active_cred, flags, td));
}
static __inline int
fo_write(fp, uio, active_cred, flags, td)
struct file *fp;
struct uio *uio;
struct ucred *active_cred;
int flags;
struct thread *td;
{
return ((*fp->f_ops->fo_write)(fp, uio, active_cred, flags, td));
}
static __inline int
fo_ioctl(fp, com, data, active_cred, td)
struct file *fp;
u_long com;
void *data;
struct ucred *active_cred;
struct thread *td;
{
return ((*fp->f_ops->fo_ioctl)(fp, com, data, active_cred, td));
}
static __inline int
fo_poll(fp, events, active_cred, td)
struct file *fp;
int events;
struct ucred *active_cred;
struct thread *td;
{
return ((*fp->f_ops->fo_poll)(fp, events, active_cred, td));
}
static __inline int
fo_stat(fp, sb, active_cred, td)
struct file *fp;
struct stat *sb;
struct ucred *active_cred;
struct thread *td;
{
return ((*fp->f_ops->fo_stat)(fp, sb, active_cred, td));
}
static __inline int
fo_close(fp, td)
struct file *fp;
struct thread *td;
{
return ((*fp->f_ops->fo_close)(fp, td));
}
static __inline int
fo_kqfilter(fp, kn)
struct file *fp;
struct knote *kn;
{
return ((*fp->f_ops->fo_kqfilter)(fp, kn));
}
#endif /* _KERNEL */
#endif /* !SYS_FILE_H */