diff options
Diffstat (limited to 'sys/sys/file.h')
| -rw-r--r-- | sys/sys/file.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/sys/sys/file.h b/sys/sys/file.h new file mode 100644 index 0000000..f638c15 --- /dev/null +++ b/sys/sys/file.h @@ -0,0 +1,136 @@ +/* $OpenBSD: file.h,v 1.61 2020/03/13 10:07:01 anton Exp $ */ +/* $NetBSD: file.h,v 1.11 1995/03/26 20:24:13 jtc Exp $ */ + +/* + * 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. + * 3. 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 8.2 (Berkeley) 8/20/94 + */ + +#ifndef _KERNEL +#include <sys/fcntl.h> + +#else /* _KERNEL */ +#include <sys/queue.h> +#include <sys/mutex.h> + +struct proc; +struct uio; +struct knote; +struct stat; +struct file; +struct ucred; + +/** + * File operations. + * The following entries could be called without KERNEL_LOCK hold: + * - fo_read + * - fo_write + * - fo_close + */ +struct fileops { + int (*fo_read)(struct file *, struct uio *, int); + int (*fo_write)(struct file *, struct uio *, int); + int (*fo_ioctl)(struct file *, u_long, caddr_t, struct proc *); + int (*fo_poll)(struct file *, int, struct proc *); + int (*fo_kqfilter)(struct file *, struct knote *); + int (*fo_stat)(struct file *, struct stat *, struct proc *); + int (*fo_close)(struct file *, struct proc *); + int (*fo_seek)(struct file *, off_t *, int, struct proc *); +}; +#define FO_POSITION 0x00000001 /* positioned read/write */ + +/* + * Kernel descriptor table. + * One entry for each open kernel vnode and socket. + * + * Locks used to protect struct members in this file: + * I immutable after creation + * F global `fhdlk' mutex + * a atomic operations + * f per file `f_mtx' + * v vnode lock + */ +struct file { + LIST_ENTRY(file) f_list;/* [F] list of active files */ + struct mutex f_mtx; + u_int f_flag; /* [a] see fcntl.h */ +#define DTYPE_VNODE 1 /* file */ +#define DTYPE_SOCKET 2 /* communications endpoint */ +#define DTYPE_PIPE 3 /* pipe */ +#define DTYPE_KQUEUE 4 /* event queue */ +#define DTYPE_DMABUF 5 /* DMA buffer (for DRM) */ + u_int f_iflags; /* [a] internal flags */ + int f_type; /* [I] descriptor type */ + u_int f_count; /* [a] reference count */ + struct ucred *f_cred; /* [I] credentials associated with descriptor */ + const struct fileops *f_ops; /* [I] file operation pointers */ + off_t f_offset; /* [f,v] offset */ + void *f_data; /* [I] private data */ + uint64_t f_rxfer; /* [f] total number of read transfers */ + uint64_t f_wxfer; /* [f] total number of write transfers */ + uint64_t f_seek; /* [f] total independent seek operations */ + uint64_t f_rbytes; /* [f] total bytes read */ + uint64_t f_wbytes; /* [f] total bytes written */ +}; + +#define FIF_HASLOCK 0x01 /* descriptor holds advisory lock */ +#define FIF_INSERTED 0x80 /* present in `filehead' */ + +#define FREF(fp) \ + do { \ + extern void vfs_stall_barrier(void); \ + vfs_stall_barrier(); \ + atomic_inc_int(&(fp)->f_count); \ + } while (0) + +#define FRELE(fp,p) \ + (atomic_dec_int_nv(&fp->f_count) == 0 ? fdrop(fp, p) : 0) + +#define FDUP_MAX_COUNT (UINT_MAX - 2 * MAXCPUS) + +int fdrop(struct file *, struct proc *); + +static inline off_t +foffset(struct file *fp) +{ + off_t offset; + + mtx_enter(&fp->f_mtx); + offset = fp->f_offset; + mtx_leave(&fp->f_mtx); + return (offset); +} + +LIST_HEAD(filelist, file); +extern int maxfiles; /* kernel limit on number of open files */ +extern int numfiles; /* actual number of open files */ +extern const struct fileops socketops; /* socket operations for files */ +extern const struct fileops vnops; /* vnode operations for files */ + +#endif /* _KERNEL */ |