gems-kernel/source/THIRDPARTY/xnu/bsd/sys/pipe.h
2024-06-03 11:29:39 -05:00

187 lines
6.7 KiB
C

/*
* Copyright (c) 2004-2020 Apple Computer, Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* Copyright (c) 1996 John S. Dyson
* 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 immediately at the beginning of the file, without modification,
* 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. Absolutely no warranty of function or purpose is made by the author
* John S. Dyson.
* 4. This work was done expressly for inclusion into FreeBSD. Other use
* is allowed if this notation is included.
* 5. Modifications may be freely made to this file if the above conditions
* are met.
*
* $FreeBSD: src/sys/sys/pipe.h,v 1.24 2003/08/13 20:01:38 alc Exp $
*/
/*
* NOTICE: This file was modified by SPARTA, Inc. in 2006 to introduce
* support for mandatory and extensible security protections. This notice
* is included in support of clause 2.2 (b) of the Apple Public License,
* Version 2.0.
*/
#ifndef _SYS_PIPE_H_
#define _SYS_PIPE_H_
#ifdef KERNEL
#include <libkern/locks.h>
#include <os/base.h>
#endif
#include <sys/queue.h> /* for TAILQ macros */
#include <sys/ev.h>
#include <sys/cdefs.h>
#include <sys/_types/_caddr_t.h>
#include <sys/_types/_u_int.h>
/*
* Pipe buffer size, keep moderate in value, pipes take kva space.
*/
#ifndef PIPE_SIZE
#define PIPE_SIZE 16384
#endif
#define PIPE_KVAMAX (1024 * 1024 * 16)
#ifndef BIG_PIPE_SIZE
#define BIG_PIPE_SIZE (64*1024)
#endif
#ifndef SMALL_PIPE_SIZE
#define SMALL_PIPE_SIZE PAGE_SIZE
#endif
/*
* PIPE_MINDIRECT MUST be smaller than PIPE_SIZE and MUST be bigger
* than PIPE_BUF.
*/
#ifndef PIPE_MINDIRECT
#define PIPE_MINDIRECT 8192
#endif
#define PIPENPAGES (BIG_PIPE_SIZE / PAGE_SIZE + 1)
/*
* Pipe buffer information.
* Separate in, out, cnt are used to simplify calculations.
* Buffered write is active when the buffer.cnt field is set.
*/
struct pipebuf {
u_int cnt; /* number of chars currently in buffer */
u_int in; /* in pointer */
u_int out; /* out pointer */
u_int size; /* size of buffer */
#if KERNEL
caddr_t OS_PTRAUTH_SIGNED_PTR("pipe.buffer") buffer; /* kva of buffer */
#else
caddr_t buffer; /* kva of buffer */
#endif /* KERNEL */
};
#ifdef PIPE_DIRECT
/*
* Information to support direct transfers between processes for pipes.
*/
struct pipemapping {
vm_offset_t kva; /* kernel virtual address */
vm_size_t cnt; /* number of chars in buffer */
vm_size_t pos; /* current position of transfer */
int npages; /* number of pages */
vm_page_t ms[PIPENPAGES]; /* pages in source process */
};
#endif
/*
* Bits in pipe_state.
*/
#define PIPE_ASYNC 0x004 /* Async? I/O. */
#define PIPE_WANTR 0x008 /* Reader wants some characters. */
#define PIPE_WANTW 0x010 /* Writer wants space to put characters. */
#define PIPE_WANT 0x020 /* Pipe is wanted to be run-down. */
// was PIPE_SEL 0x040 /* Pipe has a select active. */
#define PIPE_EOF 0x080 /* Pipe is in EOF condition. */
#define PIPE_LOCKFL 0x100 /* Process has exclusive access to pointers/data. */
#define PIPE_LWANT 0x200 /* Process wants exclusive access to pointers/data. */
#define PIPE_DIRECTW 0x400 /* Pipe direct write active. */
#define PIPE_DIRECTOK 0x800 /* Direct mode ok. */
// was PIPE_KNOTE 0x1000
#define PIPE_DRAIN 0x2000 /* Waiting for I/O to drop for a close. Treated like EOF;
* only separate for easier debugging. */
#define PIPE_WSELECT 0x4000 /* Some thread has done an FWRITE select on the pipe */
#define PIPE_DEAD 0x8000 /* Pipe is dead and needs garbage collection */
#ifdef KERNEL
struct label;
/*
* Per-pipe data structure.
* Two of these are linked together to produce bi-directional pipes.
*/
struct pipe {
struct pipebuf pipe_buffer; /* data storage */
#ifdef PIPE_DIRECT
struct pipemapping pipe_map; /* pipe mapping for direct I/O */
#endif
struct selinfo pipe_sel; /* for compat with select */
pid_t pipe_pgid; /* information for async I/O */
struct pipe *pipe_peer; /* link with other direction */
u_int pipe_state; /* pipe status info */
int pipe_busy; /* busy flag, mostly to handle rundown sanely */
lck_mtx_t *pipe_mtxp; /* shared mutex between both pipes */
struct timespec st_atimespec; /* time of last access */
struct timespec st_mtimespec; /* time of last data modification */
struct timespec st_ctimespec; /* time of last status change */
struct label *pipe_label; /* pipe MAC label - shared */
};
#define PIPE_MTX(pipe) ((pipe)->pipe_mtxp)
#define PIPE_LOCK(pipe) lck_mtx_lock(PIPE_MTX(pipe))
#define PIPE_UNLOCK(pipe) lck_mtx_unlock(PIPE_MTX(pipe))
#define PIPE_LOCK_ASSERT(pipe, type) LCK_MTX_ASSERT(PIPE_MTX(pipe), (type))
__BEGIN_DECLS
extern int pipe_stat(struct pipe *, void *, int);
#ifdef BSD_KERNEL_PRIVATE
extern uint64_t pipe_id(struct pipe *);
#endif
__END_DECLS
#endif /* KERNEL */
#endif /* !_SYS_PIPE_H_ */