+/*
+ * Copyright (c) 2004-2005 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License"). You may not use this file except in compliance with the
+ * License. Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
+ *
+ * This 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 OR NON-INFRINGEMENT. Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * @APPLE_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 $
+ */
+
+#ifndef _SYS_PIPE_H_
+#define _SYS_PIPE_H_
+
+#ifdef KERNEL
+#include <libkern/locks.h>
+#endif
+#include <sys/queue.h> /* for TAILQ macros */
+#include <sys/ev.h>
+#include <sys/cdefs.h>
+
+/*
+ * Pipe buffer size, keep moderate in value, pipes take kva space.
+ */
+#ifndef PIPE_SIZE
+#define PIPE_SIZE 16384
+#endif
+
+#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 */
+ caddr_t buffer; /* kva of buffer */
+};
+
+
+#ifdef PIPE_DIRECT
+/*
+ * Information to support direct transfers between processes for pipes.
+ */
+/* LP64todo - not 64bit safe */
+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. */
+#define 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. */
+#define PIPE_KNOTE 0x1000 /* Pipe has kernel events activated */
+
+#ifdef KERNEL
+/*
+ * 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 */
+#ifdef MAC
+ struct label *pipe_label; /* pipe MAC label - shared */
+#endif
+ TAILQ_HEAD(,eventqelt) pipe_evlist;
+ lck_mtx_t *pipe_mtxp; /* shared mutex between both pipes */
+};
+
+#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 *, struct stat *);
+__END_DECLS
+
+#endif /* KERNEL */
+
+#endif /* !_SYS_PIPE_H_ */
projects / apple / xnu.git / blobdiff