xref: /titanic_44/usr/src/uts/common/sys/strsubr.h (revision 5ebc22727c394636ca1111875be60eb4705d818f)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 
26 /*
27  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #ifndef _SYS_STRSUBR_H
32 #define	_SYS_STRSUBR_H
33 
34 #pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SVr4.0 1.17 */
35 
36 /*
37  * WARNING:
38  * Everything in this file is private, belonging to the
39  * STREAMS subsystem.  The only guarantee made about the
40  * contents of this file is that if you include it, your
41  * code will not port to the next release.
42  */
43 #include <sys/stream.h>
44 #include <sys/stropts.h>
45 #include <sys/kstat.h>
46 #include <sys/uio.h>
47 #include <sys/proc.h>
48 
49 #ifdef	__cplusplus
50 extern "C" {
51 #endif
52 
53 /*
54  * In general, the STREAMS locks are disjoint; they are only held
55  * locally, and not simultaneously by a thread.  However, module
56  * code, including at the stream head, requires some locks to be
57  * acquired in order for its safety.
58  *	1. Stream level claim.  This prevents the value of q_next
59  *		from changing while module code is executing.
60  *	2. Queue level claim.  This prevents the value of q_ptr
61  *		from changing while put or service code is executing.
62  *		In addition, it provides for queue single-threading
63  *		for QPAIR and PERQ MT-safe modules.
64  *	3. Stream head lock.  May be held by the stream head module
65  *		to implement a read/write/open/close monitor.
66  *	   Note: that the only types of twisted stream supported are
67  *	   the pipe and transports which have read and write service
68  *	   procedures on both sides of the twist.
69  *	4. Queue lock.  May be acquired by utility routines on
70  *		behalf of a module.
71  */
72 
73 /*
74  * In general, sd_lock protects the consistency of the stdata
75  * structure.  Additionally, it is used with sd_monitor
76  * to implement an open/close monitor.  In particular, it protects
77  * the following fields:
78  *	sd_iocblk
79  *	sd_flag
80  *	sd_copyflag
81  *	sd_iocid
82  *	sd_iocwait
83  *	sd_sidp
84  *	sd_pgidp
85  *	sd_wroff
86  *	sd_rerror
87  *	sd_werror
88  *	sd_pushcnt
89  *	sd_sigflags
90  *	sd_siglist
91  *	sd_pollist
92  *	sd_mark
93  *	sd_closetime
94  *	sd_wakeq
95  *	sd_uiordq
96  *	sd_uiowrq
97  *	sd_maxblk
98  *
99  * The following fields are modified only by the allocator, which
100  * has exclusive access to them at that time:
101  *	sd_wrq
102  *	sd_strtab
103  *
104  * The following field is protected by the overlying file system
105  * code, guaranteeing single-threading of opens:
106  *	sd_vnode
107  *
108  * Stream-level locks should be acquired before any queue-level locks
109  *	are acquired.
110  *
111  * The stream head write queue lock(sd_wrq) is used to protect the
112  * fields qn_maxpsz and qn_minpsz because freezestr() which is
113  * necessary for strqset() only gets the queue lock.
114  */
115 
116 /*
117  * Function types for the parameterized stream head.
118  * The msgfunc_t takes the parameters:
119  * 	msgfunc(vnode_t *vp, mblk_t *mp, strwakeup_t *wakeups,
120  *		strsigset_t *firstmsgsigs, strsigset_t *allmsgsigs,
121  *		strpollset_t *pollwakeups);
122  * It returns an optional message to be processed by the stream head.
123  *
124  * The parameters for errfunc_t are:
125  *	errfunc(vnode *vp, int ispeek, int *clearerr);
126  * It returns an errno and zero if there was no pending error.
127  */
128 typedef uint_t	strwakeup_t;
129 typedef uint_t	strsigset_t;
130 typedef short	strpollset_t;
131 typedef uintptr_t callbparams_id_t;
132 typedef	mblk_t	*(*msgfunc_t)(vnode_t *, mblk_t *, strwakeup_t *,
133 			strsigset_t *, strsigset_t *, strpollset_t *);
134 typedef int 	(*errfunc_t)(vnode_t *, int, int *);
135 
136 /*
137  * Per stream sd_lock in putnext may be replaced by per cpu stream_putlocks
138  * each living in a separate cache line. putnext/canputnext grabs only one of
139  * stream_putlocks while strlock() (called on behalf of insertq()/removeq())
140  * acquires all stream_putlocks. Normally stream_putlocks are only employed
141  * for highly contended streams that have SQ_CIPUT queues in the critical path
142  * (e.g. NFS/UDP stream).
143  *
144  * stream_putlocks are dynamically assigned to stdata structure through
145  * sd_ciputctrl pointer possibly when a stream is already in use. Since
146  * strlock() uses stream_putlocks only under sd_lock acquiring sd_lock when
147  * assigning stream_putlocks to the stream ensures synchronization with
148  * strlock().
149  *
150  * For lock ordering purposes stream_putlocks are treated as the extension of
151  * sd_lock and are always grabbed right after grabbing sd_lock and released
152  * right before releasing sd_lock except putnext/canputnext where only one of
153  * stream_putlocks locks is used and where it is the first lock to grab.
154  */
155 
156 typedef struct ciputctrl_str {
157 	union _ciput_un {
158 		uchar_t	pad[64];
159 		struct _ciput_str {
160 			kmutex_t	ciput_lck;
161 			ushort_t	ciput_cnt;
162 		} ciput_str;
163 	} ciput_un;
164 } ciputctrl_t;
165 
166 #define	ciputctrl_lock	ciput_un.ciput_str.ciput_lck
167 #define	ciputctrl_count	ciput_un.ciput_str.ciput_cnt
168 
169 /*
170  * Header for a stream: interface to rest of system.
171  */
172 typedef struct stdata {
173 	struct queue	*sd_wrq;	/* write queue */
174 	struct msgb	*sd_iocblk;	/* return block for ioctl */
175 	struct vnode	*sd_vnode;	/* pointer to associated vnode */
176 	struct streamtab *sd_strtab;	/* pointer to streamtab for stream */
177 	uint_t		sd_flag;	/* state/flags */
178 	uint_t		sd_iocid;	/* ioctl id */
179 	struct pid	*sd_sidp;	/* controlling session info */
180 	struct pid	*sd_pgidp;	/* controlling process group info */
181 	ushort_t	sd_unused;	/* UNUSED, retained for binary */
182 					/* compatibility */
183 	ushort_t	sd_wroff;	/* write offset */
184 	int		sd_rerror;	/* error to return on read ops */
185 	int		sd_werror;	/* error to return on write ops */
186 	int		sd_pushcnt;	/* number of pushes done on stream */
187 	int		sd_sigflags;	/* logical OR of all siglist events */
188 	struct strsig	*sd_siglist;	/* pid linked list to rcv SIGPOLL sig */
189 	struct pollhead sd_pollist;	/* list of all pollers to wake up */
190 	struct msgb	*sd_mark;	/* "marked" message on read queue */
191 	clock_t		sd_closetime;	/* time to wait to drain q in close */
192 	kmutex_t	sd_lock;	/* protect head consistency */
193 	kcondvar_t	sd_monitor;	/* open/close/push/pop monitor */
194 	kcondvar_t	sd_iocmonitor;	/* ioctl single-threading */
195 	kcondvar_t	sd_refmonitor;	/* sd_refcnt monitor */
196 	ssize_t		sd_qn_minpsz;	/* These two fields are a performance */
197 	ssize_t		sd_qn_maxpsz;	/* enhancements, cache the values in */
198 					/* the stream head so we don't have */
199 					/* to ask the module below the stream */
200 					/* head to get this information. */
201 	struct stdata	*sd_mate;	/* pointer to twisted stream mate */
202 	kthread_id_t	sd_freezer;	/* thread that froze stream */
203 	kmutex_t	sd_reflock;	/* Protects sd_refcnt */
204 	int		sd_refcnt;	/* number of claimstr */
205 	uint_t		sd_wakeq;	/* strwakeq()'s copy of sd_flag */
206 	struct queue	*sd_struiordq;	/* sync barrier struio() read queue */
207 	struct queue	*sd_struiowrq;	/* sync barrier struio() write queue */
208 	char		sd_struiodnak;	/* defer NAK of M_IOCTL by rput() */
209 	struct msgb	*sd_struionak;	/* pointer M_IOCTL mblk(s) to NAK */
210 	caddr_t		sd_t_audit_data; /* For audit purposes only */
211 	ssize_t		sd_maxblk;	/* maximum message block size */
212 	uint_t		sd_rput_opt;	/* options/flags for strrput */
213 	uint_t		sd_wput_opt;	/* options/flags for write/putmsg */
214 	uint_t		sd_read_opt;	/* options/flags for strread */
215 	msgfunc_t	sd_rprotofunc;	/* rput M_*PROTO routine */
216 	msgfunc_t	sd_rmiscfunc;	/* rput routine (non-data/proto) */
217 	errfunc_t	sd_rderrfunc;	/* read side error callback */
218 	errfunc_t	sd_wrerrfunc;	/* write side error callback */
219 	/*
220 	 * support for low contention concurrent putnext.
221 	 */
222 	ciputctrl_t	*sd_ciputctrl;
223 	uint_t		sd_nciputctrl;
224 
225 	int		sd_anchor;	/* position of anchor in stream */
226 	/*
227 	 * Service scheduling at the stream head.
228 	 */
229 	kmutex_t	sd_qlock;
230 	struct queue	*sd_qhead;	/* Head of queues to be serviced. */
231 	struct queue	*sd_qtail;	/* Tail of queues to be serviced. */
232 	void		*sd_servid;	/* Service ID for bckgrnd schedule */
233 	ushort_t	sd_svcflags;	/* Servicing flags */
234 	short		sd_nqueues;	/* Number of queues in the list */
235 	kcondvar_t	sd_qcv;		/* Waiters for qhead to become empty */
236 	kcondvar_t	sd_zcopy_wait;
237 	uint_t		sd_copyflag;	/* copy-related flags */
238 } stdata_t;
239 
240 /*
241  * stdata servicing flags.
242  */
243 #define	STRS_WILLSERVICE	0x01
244 #define	STRS_SCHEDULED		0x02
245 
246 #define	STREAM_NEEDSERVICE(stp)	((stp)->sd_qhead != NULL)
247 
248 /*
249  * stdata flag field defines
250  */
251 #define	IOCWAIT		0x00000001	/* Someone is doing an ioctl */
252 #define	RSLEEP		0x00000002	/* Someone wants to read/recv msg */
253 #define	WSLEEP		0x00000004	/* Someone wants to write */
254 #define	STRPRI		0x00000008	/* An M_PCPROTO is at stream head */
255 #define	STRHUP		0x00000010	/* Device has vanished */
256 #define	STWOPEN		0x00000020	/* waiting for 1st open */
257 #define	STPLEX		0x00000040	/* stream is being multiplexed */
258 #define	STRISTTY	0x00000080	/* stream is a terminal */
259 #define	STRGETINPROG	0x00000100	/* (k)strgetmsg is running */
260 #define	IOCWAITNE	0x00000200	/* STR_NOERROR ioctl running */
261 #define	STRDERR		0x00000400	/* fatal read error from M_ERROR */
262 #define	STWRERR		0x00000800	/* fatal write error from M_ERROR */
263 #define	STRDERRNONPERSIST 0x00001000	/* nonpersistent read errors */
264 #define	STWRERRNONPERSIST 0x00002000	/* nonpersistent write errors */
265 #define	STRCLOSE	0x00004000	/* wait for a close to complete */
266 #define	SNDMREAD	0x00008000	/* used for read notification */
267 #define	OLDNDELAY	0x00010000	/* use old TTY semantics for */
268 					/* NDELAY reads and writes */
269 	/*		0x00020000	   unused */
270 	/*		0x00040000	   unused */
271 #define	STRTOSTOP	0x00080000	/* block background writes */
272 	/*		0x00100000	   unused */
273 	/*		0x00200000	   unused */
274 #define	STRMOUNT	0x00400000	/* stream is mounted */
275 #define	STRNOTATMARK	0x00800000	/* Not at mark (when empty read q) */
276 #define	STRDELIM	0x01000000	/* generate delimited messages */
277 #define	STRATMARK	0x02000000	/* At mark (due to MSGMARKNEXT) */
278 #define	STZCNOTIFY	0x04000000	/* wait for zerocopy mblk to be acked */
279 #define	STRPLUMB	0x08000000	/* push/pop pending */
280 #define	STREOF		0x10000000	/* End-of-file indication */
281 #define	STREOPENFAIL	0x20000000	/* indicates if re-open has failed */
282 #define	STRMATE		0x40000000	/* this stream is a mate */
283 #define	STRHASLINKS	0x80000000	/* I_LINKs under this stream */
284 
285 /*
286  * Copy-related flags (sd_copyflag), set by SO_COPYOPT.
287  */
288 #define	STZCVMSAFE	0x00000001	/* safe to borrow file (segmapped) */
289 					/* pages instead of bcopy */
290 #define	STZCVMUNSAFE	0x00000002	/* unsafe to borrow file pages */
291 #define	STRCOPYCACHED	0x00000004	/* copy should NOT bypass cache */
292 
293 /*
294  * Options and flags for strrput (sd_rput_opt)
295  */
296 #define	SR_POLLIN	0x00000001	/* pollwakeup needed for band0 data */
297 #define	SR_SIGALLDATA	0x00000002	/* Send SIGPOLL for all M_DATA */
298 #define	SR_CONSOL_DATA	0x00000004	/* Consolidate M_DATA onto q_last */
299 #define	SR_IGN_ZEROLEN	0x00000008	/* Ignore zero-length M_DATA */
300 
301 /*
302  * Options and flags for strwrite/strputmsg (sd_wput_opt)
303  */
304 #define	SW_SIGPIPE	0x00000001	/* Send SIGPIPE for write error */
305 #define	SW_RECHECK_ERR	0x00000002	/* Recheck errors in strwrite loop */
306 #define	SW_SNDZERO	0x00000004	/* send 0-length msg down pipe/FIFO */
307 
308 /*
309  * Options and flags for strread (sd_read_opt)
310  */
311 #define	RD_MSGDIS	0x00000001	/* read msg discard */
312 #define	RD_MSGNODIS	0x00000002	/* read msg no discard */
313 #define	RD_PROTDAT	0x00000004	/* read M_[PC]PROTO contents as data */
314 #define	RD_PROTDIS	0x00000008	/* discard M_[PC]PROTO blocks and */
315 					/* retain data blocks */
316 /*
317  * Flags parameter for strsetrputhooks() and strsetwputhooks().
318  * These flags define the interface for setting the above internal
319  * flags in sd_rput_opt and sd_wput_opt.
320  */
321 #define	SH_CONSOL_DATA	0x00000001	/* Consolidate M_DATA onto q_last */
322 #define	SH_SIGALLDATA	0x00000002	/* Send SIGPOLL for all M_DATA */
323 #define	SH_IGN_ZEROLEN	0x00000004	/* Drop zero-length M_DATA */
324 
325 #define	SH_SIGPIPE	0x00000100	/* Send SIGPIPE for write error */
326 #define	SH_RECHECK_ERR	0x00000200	/* Recheck errors in strwrite loop */
327 
328 /*
329  * Each queue points to a sync queue (the inner perimeter) which keeps
330  * track of the number of threads that are inside a given queue (sq_count)
331  * and also is used to implement the asynchronous putnext
332  * (by queuing messages if the queue can not be entered.)
333  *
334  * Messages are queued on sq_head/sq_tail including deferred qwriter(INNER)
335  * messages. The sq_head/sq_tail list is a singly-linked list with
336  * b_queue recording the queue and b_prev recording the function to
337  * be called (either the put procedure or a qwriter callback function.)
338  *
339  * The sq_count counter tracks the number of threads that are
340  * executing inside the perimeter or (in the case of outer perimeters)
341  * have some work queued for them relating to the perimeter. The sq_rmqcount
342  * counter tracks the subset which are in removeq() (usually invoked from
343  * qprocsoff(9F)).
344  *
345  * In addition a module writer can declare that the module has an outer
346  * perimeter (by setting D_MTOUTPERIM) in which case all inner perimeter
347  * syncq's for the module point (through sq_outer) to an outer perimeter
348  * syncq. The outer perimeter consists of the doubly linked list (sq_onext and
349  * sq_oprev) linking all the inner perimeter syncq's with out outer perimeter
350  * syncq. This is used to implement qwriter(OUTER) (an asynchronous way of
351  * getting exclusive access at the outer perimeter) and outer_enter/exit
352  * which are used by the framework to acquire exclusive access to the outer
353  * perimeter during open and close of modules that have set D_MTOUTPERIM.
354  *
355  * In the inner perimeter case sq_save is available for use by machine
356  * dependent code. sq_head/sq_tail are used to queue deferred messages on
357  * the inner perimeter syncqs and to queue become_writer requests on the
358  * outer perimeter syncqs.
359  *
360  * Note: machine dependent optimized versions of putnext may depend
361  * on the order of sq_flags and sq_count (so that they can e.g.
362  * read these two fields in a single load instruction.)
363  *
364  * Per perimeter SQLOCK/sq_count in putnext/put may be replaced by per cpu
365  * sq_putlocks/sq_putcounts each living in a separate cache line. Obviously
366  * sq_putlock[x] protects sq_putcount[x]. putnext/put routine will grab only 1
367  * of sq_putlocks and update only 1 of sq_putcounts. strlock() and many
368  * other routines in strsubr.c and ddi.c will grab all sq_putlocks (as well as
369  * SQLOCK) and figure out the count value as the sum of sq_count and all of
370  * sq_putcounts. The idea is to make critical fast path -- putnext -- much
371  * faster at the expense of much less often used slower path like
372  * strlock(). One known case where entersq/strlock is executed pretty often is
373  * SpecWeb but since IP is SQ_CIOC and socket TCP/IP stream is nextless
374  * there's no need to grab multiple sq_putlocks and look at sq_putcounts. See
375  * strsubr.c for more comments.
376  *
377  * Note regular SQLOCK and sq_count are still used in many routines
378  * (e.g. entersq(), rwnext()) in the same way as before sq_putlocks were
379  * introduced.
380  *
381  * To understand when all sq_putlocks need to be held and all sq_putcounts
382  * need to be added up one needs to look closely at putnext code. Basically if
383  * a routine like e.g. wait_syncq() needs to be sure that perimeter is empty
384  * all sq_putlocks/sq_putcounts need to be held/added up. On the other hand
385  * there's no need to hold all sq_putlocks and count all sq_putcounts in
386  * routines like leavesq()/dropsq() and etc. since the are usually exit
387  * counterparts of entersq/outer_enter() and etc. which have already either
388  * prevented put entry poins from executing or did not care about put
389  * entrypoints. entersq() doesn't need to care about sq_putlocks/sq_putcounts
390  * if the entry point has a shared access since put has the highest degree of
391  * concurrency and such entersq() does not intend to block out put
392  * entrypoints.
393  *
394  * Before sq_putcounts were introduced the standard way to wait for perimeter
395  * to become empty was:
396  *
397  *	mutex_enter(SQLOCK(sq));
398  *	while (sq->sq_count > 0) {
399  *		sq->sq_flags |= SQ_WANTWAKEUP;
400  *		cv_wait(&sq->sq_wait, SQLOCK(sq));
401  *	}
402  *	mutex_exit(SQLOCK(sq));
403  *
404  * The new way is:
405  *
406  * 	mutex_enter(SQLOCK(sq));
407  *	count = sq->sq_count;
408  *	SQ_PUTLOCKS_ENTER(sq);
409  *	SUM_SQ_PUTCOUNTS(sq, count);
410  *	while (count != 0) {
411  *		sq->sq_flags |= SQ_WANTWAKEUP;
412  *		SQ_PUTLOCKS_EXIT(sq);
413  *		cv_wait(&sq->sq_wait, SQLOCK(sq));
414  *		count = sq->sq_count;
415  *		SQ_PUTLOCKS_ENTER(sq);
416  *		SUM_SQ_PUTCOUNTS(sq, count);
417  *	}
418  *	SQ_PUTLOCKS_EXIT(sq);
419  *	mutex_exit(SQLOCK(sq));
420  *
421  * Note that SQ_WANTWAKEUP is set before dropping SQ_PUTLOCKS. This makes sure
422  * putnext won't skip a wakeup.
423  *
424  * sq_putlocks are treated as the extension of SQLOCK for lock ordering
425  * purposes and are always grabbed right after grabbing SQLOCK and released
426  * right before releasing SQLOCK. This also allows dynamic creation of
427  * sq_putlocks while holding SQLOCK (by making sq_ciputctrl non null even when
428  * the stream is already in use). Only in putnext one of sq_putlocks
429  * is grabbed instead of SQLOCK. putnext return path remembers what counter it
430  * incremented and decrements the right counter on its way out.
431  */
432 
433 struct syncq {
434 	kmutex_t	sq_lock;	/* atomic access to syncq */
435 	uint16_t	sq_count;	/* # threads inside */
436 	uint16_t	sq_flags;	/* state and some type info */
437 	/*
438 	 * Distributed syncq scheduling
439 	 *  The list of queue's is handled by sq_head and
440 	 *  sq_tail fields.
441 	 *
442 	 *  The list of events is handled by the sq_evhead and sq_evtail
443 	 *  fields.
444 	 */
445 	queue_t		*sq_head;	/* queue of deferred messages */
446 	queue_t		*sq_tail;	/* queue of deferred messages */
447 	mblk_t		*sq_evhead;	/* Event message on the syncq */
448 	mblk_t		*sq_evtail;
449 	uint_t		sq_nqueues;	/* # of queues on this sq */
450 	/*
451 	 * Concurrency and condition variables
452 	 */
453 	uint16_t	sq_type;	/* type (concurrency) of syncq */
454 	uint16_t	sq_rmqcount;	/* # threads inside removeq() */
455 	kcondvar_t 	sq_wait;	/* block on this sync queue */
456 	kcondvar_t 	sq_exitwait;	/* waiting for thread to leave the */
457 					/* inner perimeter */
458 	/*
459 	 * Handling synchronous callbacks such as qtimeout and qbufcall
460 	 */
461 	ushort_t	sq_callbflags;	/* flags for callback synchronization */
462 	callbparams_id_t sq_cancelid;	/* id of callback being cancelled */
463 	struct callbparams *sq_callbpend;	/* Pending callbacks */
464 
465 	/*
466 	 * Links forming an outer perimeter from one outer syncq and
467 	 * a set of inner sync queues.
468 	 */
469 	struct syncq	*sq_outer;	/* Pointer to outer perimeter */
470 	struct syncq	*sq_onext;	/* Linked list of syncq's making */
471 	struct syncq	*sq_oprev;	/* up the outer perimeter. */
472 	/*
473 	 * support for low contention concurrent putnext.
474 	 */
475 	ciputctrl_t	*sq_ciputctrl;
476 	uint_t		sq_nciputctrl;
477 	/*
478 	 * Counter for the number of threads wanting to become exclusive.
479 	 */
480 	uint_t		sq_needexcl;
481 	/*
482 	 * These two fields are used for scheduling a syncq for
483 	 * background processing. The sq_svcflag is protected by
484 	 * SQLOCK lock.
485 	 */
486 	struct syncq	*sq_next;	/* for syncq scheduling */
487 	void *		sq_servid;
488 	uint_t		sq_servcount;	/* # pending background threads */
489 	uint_t		sq_svcflags;	/* Scheduling flags	*/
490 	clock_t		sq_tstamp;	/* Time when was enabled */
491 	/*
492 	 * Maximum priority of the queues on this syncq.
493 	 */
494 	pri_t		sq_pri;
495 };
496 typedef struct syncq syncq_t;
497 
498 /*
499  * sync queue scheduling flags (for sq_svcflags).
500  */
501 #define	SQ_SERVICE	0x1		/* being serviced */
502 #define	SQ_BGTHREAD	0x2		/* awaiting service by bg thread */
503 #define	SQ_DISABLED	0x4		/* don't put syncq in service list */
504 
505 /*
506  * FASTPUT bit in sd_count/putcount.
507  */
508 #define	SQ_FASTPUT	0x8000
509 #define	SQ_FASTMASK	0x7FFF
510 
511 /*
512  * sync queue state flags
513  */
514 #define	SQ_EXCL		0x0001		/* exclusive access to inner */
515 					/*	perimeter */
516 #define	SQ_BLOCKED	0x0002		/* qprocsoff */
517 #define	SQ_FROZEN	0x0004		/* freezestr */
518 #define	SQ_WRITER	0x0008		/* qwriter(OUTER) pending or running */
519 #define	SQ_MESSAGES	0x0010		/* messages on syncq */
520 #define	SQ_WANTWAKEUP	0x0020		/* do cv_broadcast on sq_wait */
521 #define	SQ_WANTEXWAKEUP	0x0040		/* do cv_broadcast on sq_exitwait */
522 #define	SQ_EVENTS	0x0080		/* Events pending */
523 #define	SQ_QUEUED	(SQ_MESSAGES | SQ_EVENTS)
524 #define	SQ_FLAGMASK	0x00FF
525 
526 /*
527  * Test a queue to see if inner perimeter is exclusive.
528  */
529 #define	PERIM_EXCL(q)	((q)->q_syncq->sq_flags & SQ_EXCL)
530 
531 /*
532  * If any of these flags are set it is not possible for a thread to
533  * enter a put or service procedure. Instead it must either block
534  * or put the message on the syncq.
535  */
536 #define	SQ_GOAWAY	(SQ_EXCL|SQ_BLOCKED|SQ_FROZEN|SQ_WRITER|\
537 			SQ_QUEUED)
538 /*
539  * If any of these flags are set it not possible to drain the syncq
540  */
541 #define	SQ_STAYAWAY	(SQ_BLOCKED|SQ_FROZEN|SQ_WRITER)
542 
543 /*
544  * Flags to trigger syncq tail processing.
545  */
546 #define	SQ_TAIL		(SQ_QUEUED|SQ_WANTWAKEUP|SQ_WANTEXWAKEUP)
547 
548 /*
549  * Syncq types (stored in sq_type)
550  * The SQ_TYPES_IN_FLAGS (ciput) are also stored in sq_flags
551  * for performance reasons. Thus these type values have to be in the low
552  * 16 bits and not conflict with the sq_flags values above.
553  *
554  * Notes:
555  *  - putnext() and put() assume that the put procedures have the highest
556  *    degree of concurrency. Thus if any of the SQ_CI* are set then SQ_CIPUT
557  *    has to be set. This restriction can be lifted by adding code to putnext
558  *    and put that check that sq_count == 0 like entersq does.
559  *  - putnext() and put() does currently not handle !SQ_COPUT
560  *  - In order to implement !SQ_COCB outer_enter has to be fixed so that
561  *    the callback can be cancelled while cv_waiting in outer_enter.
562  *  - If SQ_CISVC needs to be implemented, qprocsoff() needs to wait
563  *    for the currently running services to stop (wait for QINSERVICE
564  *    to go off). disable_svc called from qprcosoff disables only
565  *    services that will be run in future.
566  *
567  * All the SQ_CO flags are set when there is no outer perimeter.
568  */
569 #define	SQ_CIPUT	0x0100		/* Concurrent inner put proc */
570 #define	SQ_CISVC	0x0200		/* Concurrent inner svc proc */
571 #define	SQ_CIOC		0x0400		/* Concurrent inner open/close */
572 #define	SQ_CICB		0x0800		/* Concurrent inner callback */
573 #define	SQ_COPUT	0x1000		/* Concurrent outer put proc */
574 #define	SQ_COSVC	0x2000		/* Concurrent outer svc proc */
575 #define	SQ_COOC		0x4000		/* Concurrent outer open/close */
576 #define	SQ_COCB		0x8000		/* Concurrent outer callback */
577 
578 /* Types also kept in sq_flags for performance */
579 #define	SQ_TYPES_IN_FLAGS	(SQ_CIPUT)
580 
581 #define	SQ_CI		(SQ_CIPUT|SQ_CISVC|SQ_CIOC|SQ_CICB)
582 #define	SQ_CO		(SQ_COPUT|SQ_COSVC|SQ_COOC|SQ_COCB)
583 #define	SQ_TYPEMASK	(SQ_CI|SQ_CO)
584 
585 /*
586  * Flag combinations passed to entersq and leavesq to specify the type
587  * of entry point.
588  */
589 #define	SQ_PUT		(SQ_CIPUT|SQ_COPUT)
590 #define	SQ_SVC		(SQ_CISVC|SQ_COSVC)
591 #define	SQ_OPENCLOSE	(SQ_CIOC|SQ_COOC)
592 #define	SQ_CALLBACK	(SQ_CICB|SQ_COCB)
593 
594 /*
595  * Other syncq types which are not copied into flags.
596  */
597 #define	SQ_PERMOD	0x01		/* Syncq is PERMOD */
598 
599 /*
600  * Asynchronous callback qun*** flag.
601  * The mechanism these flags are used in is one where callbacks enter
602  * the perimeter thanks to framework support. To use this mechanism
603  * the q* and qun* flavors of the callback routines must be used.
604  * e.g. qtimeout and quntimeout. The synchronization provided by the flags
605  * avoids deadlocks between blocking qun* routines and the perimeter
606  * lock.
607  */
608 #define	SQ_CALLB_BYPASSED	0x01		/* bypassed callback fn */
609 
610 /*
611  * Cancel callback mask.
612  * The mask expands as the number of cancelable callback types grows
613  * Note - separate callback flag because different callbacks have
614  * overlapping id space.
615  */
616 #define	SQ_CALLB_CANCEL_MASK	(SQ_CANCEL_TOUT|SQ_CANCEL_BUFCALL)
617 
618 #define	SQ_CANCEL_TOUT		0x02		/* cancel timeout request */
619 #define	SQ_CANCEL_BUFCALL	0x04		/* cancel bufcall request */
620 
621 typedef struct callbparams {
622 	syncq_t		*cbp_sq;
623 	void		(*cbp_func)(void *);
624 	void		*cbp_arg;
625 	callbparams_id_t cbp_id;
626 	uint_t		cbp_flags;
627 	struct callbparams *cbp_next;
628 	size_t		cbp_size;
629 } callbparams_t;
630 
631 typedef struct strbufcall {
632 	void		(*bc_func)(void *);
633 	void		*bc_arg;
634 	size_t		bc_size;
635 	bufcall_id_t	bc_id;
636 	struct strbufcall *bc_next;
637 	kthread_id_t	bc_executor;
638 } strbufcall_t;
639 
640 /*
641  * Structure of list of processes to be sent SIGPOLL/SIGURG signal
642  * on request.  The valid S_* events are defined in stropts.h.
643  */
644 typedef struct strsig {
645 	struct pid	*ss_pidp;	/* pid/pgrp pointer */
646 	pid_t		ss_pid;		/* positive pid, negative pgrp */
647 	int		ss_events;	/* S_* events */
648 	struct strsig	*ss_next;
649 } strsig_t;
650 
651 /*
652  * bufcall list
653  */
654 struct bclist {
655 	strbufcall_t	*bc_head;
656 	strbufcall_t	*bc_tail;
657 };
658 
659 /*
660  * Structure used to track mux links and unlinks.
661  */
662 struct mux_node {
663 	major_t		 mn_imaj;	/* internal major device number */
664 	uint16_t	 mn_indegree;	/* number of incoming edges */
665 	struct mux_node *mn_originp;	/* where we came from during search */
666 	struct mux_edge *mn_startp;	/* where search left off in mn_outp */
667 	struct mux_edge *mn_outp;	/* list of outgoing edges */
668 	uint_t		 mn_flags;	/* see below */
669 };
670 
671 /*
672  * Flags for mux_nodes.
673  */
674 #define	VISITED	1
675 
676 /*
677  * Edge structure - a list of these is hung off the
678  * mux_node to represent the outgoing edges.
679  */
680 struct mux_edge {
681 	struct mux_node	*me_nodep;	/* edge leads to this node */
682 	struct mux_edge	*me_nextp;	/* next edge */
683 	int		 me_muxid;	/* id of link */
684 };
685 
686 /*
687  * Queue info
688  *
689  * The syncq is included here to reduce memory fragmentation
690  * for kernel memory allocators that only allocate in sizes that are
691  * powers of two. If the kernel memory allocator changes this should
692  * be revisited.
693  */
694 typedef struct queinfo {
695 	struct queue	qu_rqueue;	/* read queue - must be first */
696 	struct queue	qu_wqueue;	/* write queue - must be second */
697 	struct syncq	qu_syncq;	/* syncq - must be third */
698 } queinfo_t;
699 
700 /*
701  * Multiplexed streams info
702  */
703 typedef struct linkinfo {
704 	struct linkblk	li_lblk;	/* must be first */
705 	struct file	*li_fpdown;	/* file pointer for lower stream */
706 	struct linkinfo	*li_next;	/* next in list */
707 	struct linkinfo *li_prev;	/* previous in list */
708 } linkinfo_t;
709 
710 /*
711  * List of syncq's used by freeezestr/unfreezestr
712  */
713 typedef struct syncql {
714 	struct syncql	*sql_next;
715 	syncq_t		*sql_sq;
716 } syncql_t;
717 
718 typedef struct sqlist {
719 	syncql_t	*sqlist_head;
720 	size_t		sqlist_size;		/* structure size in bytes */
721 	size_t		sqlist_index;		/* next free entry in array */
722 	syncql_t	sqlist_array[4];	/* 4 or more entries */
723 } sqlist_t;
724 
725 typedef struct perdm {
726 	struct perdm		*dm_next;
727 	syncq_t			*dm_sq;
728 	struct streamtab	*dm_str;
729 	uint_t			dm_ref;
730 } perdm_t;
731 
732 #define	NEED_DM(dmp, qflag) \
733 	(dmp == NULL && (qflag & (QPERMOD | QMTOUTPERIM)))
734 
735 /*
736  * fmodsw_impl_t is used within the kernel. fmodsw is used by
737  * the modules/drivers. The information is copied from fmodsw
738  * defined in the module/driver into the fmodsw_impl_t structure
739  * during the module/driver initialization.
740  */
741 typedef struct fmodsw_impl	fmodsw_impl_t;
742 
743 struct fmodsw_impl {
744 	fmodsw_impl_t		*f_next;
745 	char			f_name[FMNAMESZ + 1];
746 	struct streamtab	*f_str;
747 	uint32_t		f_qflag;
748 	uint32_t		f_sqtype;
749 	perdm_t			*f_dmp;
750 	uint32_t		f_ref;
751 	uint32_t		f_hits;
752 };
753 
754 typedef enum {
755 	FMODSW_HOLD =	0x00000001,
756 	FMODSW_LOAD =	0x00000002
757 } fmodsw_flags_t;
758 
759 typedef struct cdevsw_impl {
760 	struct streamtab	*d_str;
761 	uint32_t		d_qflag;
762 	uint32_t		d_sqtype;
763 	perdm_t			*d_dmp;
764 } cdevsw_impl_t;
765 
766 /*
767  * Enumeration of the types of access that can be requested for a
768  * controlling terminal under job control.
769  */
770 enum jcaccess {
771 	JCREAD,			/* read data on a ctty */
772 	JCWRITE,		/* write data to a ctty */
773 	JCSETP,			/* set ctty parameters */
774 	JCGETP			/* get ctty parameters */
775 };
776 
777 /*
778  * Finding related queues
779  */
780 #define	STREAM(q)	((q)->q_stream)
781 #define	SQ(rq)		((syncq_t *)((rq) + 2))
782 
783 /*
784  * Locking macros
785  */
786 #define	QLOCK(q)	(&(q)->q_lock)
787 #define	SQLOCK(sq)	(&(sq)->sq_lock)
788 
789 #define	STREAM_PUTLOCKS_ENTER(stp) {					       \
790 		ASSERT(MUTEX_HELD(&(stp)->sd_lock));			       \
791 		if ((stp)->sd_ciputctrl != NULL) {			       \
792 			int i;						       \
793 			int nlocks = (stp)->sd_nciputctrl;		       \
794 			ciputctrl_t *cip = (stp)->sd_ciputctrl;		       \
795 			for (i = 0; i <= nlocks; i++) {			       \
796 				mutex_enter(&cip[i].ciputctrl_lock);	       \
797 			}						       \
798 		}							       \
799 	}
800 
801 #define	STREAM_PUTLOCKS_EXIT(stp) {					       \
802 		ASSERT(MUTEX_HELD(&(stp)->sd_lock));			       \
803 		if ((stp)->sd_ciputctrl != NULL) {			       \
804 			int i;						       \
805 			int nlocks = (stp)->sd_nciputctrl;		       \
806 			ciputctrl_t *cip = (stp)->sd_ciputctrl;		       \
807 			for (i = 0; i <= nlocks; i++) {			       \
808 				mutex_exit(&cip[i].ciputctrl_lock);	       \
809 			}						       \
810 		}							       \
811 	}
812 
813 #define	SQ_PUTLOCKS_ENTER(sq) {						       \
814 		ASSERT(MUTEX_HELD(SQLOCK(sq)));				       \
815 		if ((sq)->sq_ciputctrl != NULL) {			       \
816 			int i;						       \
817 			int nlocks = (sq)->sq_nciputctrl;		       \
818 			ciputctrl_t *cip = (sq)->sq_ciputctrl;		       \
819 			ASSERT((sq)->sq_type & SQ_CIPUT);		       \
820 			for (i = 0; i <= nlocks; i++) {			       \
821 				mutex_enter(&cip[i].ciputctrl_lock);	       \
822 			}						       \
823 		}							       \
824 	}
825 
826 #define	SQ_PUTLOCKS_EXIT(sq) {						       \
827 		ASSERT(MUTEX_HELD(SQLOCK(sq)));				       \
828 		if ((sq)->sq_ciputctrl != NULL) {			       \
829 			int i;						       \
830 			int nlocks = (sq)->sq_nciputctrl;		       \
831 			ciputctrl_t *cip = (sq)->sq_ciputctrl;		       \
832 			ASSERT((sq)->sq_type & SQ_CIPUT);		       \
833 			for (i = 0; i <= nlocks; i++) {			       \
834 				mutex_exit(&cip[i].ciputctrl_lock);	       \
835 			}						       \
836 		}							       \
837 	}
838 
839 #define	SQ_PUTCOUNT_SETFAST(sq) {					\
840 		ASSERT(MUTEX_HELD(SQLOCK(sq)));				\
841 		if ((sq)->sq_ciputctrl != NULL) {			\
842 			int i;						\
843 			int nlocks = (sq)->sq_nciputctrl;		\
844 			ciputctrl_t *cip = (sq)->sq_ciputctrl;		\
845 			ASSERT((sq)->sq_type & SQ_CIPUT);		\
846 			for (i = 0; i <= nlocks; i++) {			\
847 				mutex_enter(&cip[i].ciputctrl_lock);	\
848 				cip[i].ciputctrl_count |= SQ_FASTPUT;	\
849 				mutex_exit(&cip[i].ciputctrl_lock);	\
850 			}						\
851 		}							\
852 	}
853 
854 #define	SQ_PUTCOUNT_CLRFAST(sq) {					\
855 		ASSERT(MUTEX_HELD(SQLOCK(sq)));				\
856 		if ((sq)->sq_ciputctrl != NULL) {			\
857 			int i;						\
858 			int nlocks = (sq)->sq_nciputctrl;		\
859 			ciputctrl_t *cip = (sq)->sq_ciputctrl;		\
860 			ASSERT((sq)->sq_type & SQ_CIPUT);		\
861 			for (i = 0; i <= nlocks; i++) {			\
862 				mutex_enter(&cip[i].ciputctrl_lock);	\
863 				cip[i].ciputctrl_count &= ~SQ_FASTPUT;	\
864 				mutex_exit(&cip[i].ciputctrl_lock);	\
865 			}						\
866 		}							\
867 	}
868 
869 
870 #ifdef	DEBUG
871 
872 #define	SQ_PUTLOCKS_HELD(sq) {						       \
873 		ASSERT(MUTEX_HELD(SQLOCK(sq)));				       \
874 		if ((sq)->sq_ciputctrl != NULL) {			       \
875 			int i;						       \
876 			int nlocks = (sq)->sq_nciputctrl;		       \
877 			ciputctrl_t *cip = (sq)->sq_ciputctrl;		       \
878 			ASSERT((sq)->sq_type & SQ_CIPUT);		       \
879 			for (i = 0; i <= nlocks; i++) {			       \
880 				ASSERT(MUTEX_HELD(&cip[i].ciputctrl_lock));    \
881 			}						       \
882 		}							       \
883 	}
884 
885 #define	SUMCHECK_SQ_PUTCOUNTS(sq, countcheck) {				       \
886 		if ((sq)->sq_ciputctrl != NULL) {			       \
887 			int i;						       \
888 			uint_t count = 0;				       \
889 			int ncounts = (sq)->sq_nciputctrl;		       \
890 			ASSERT((sq)->sq_type & SQ_CIPUT);		       \
891 			for (i = 0; i <= ncounts; i++) {		       \
892 				count +=				       \
893 				    (((sq)->sq_ciputctrl[i].ciputctrl_count) & \
894 				    SQ_FASTMASK);			       \
895 			}						       \
896 			ASSERT(count == (countcheck));			       \
897 		}							       \
898 	}
899 
900 #define	SUMCHECK_CIPUTCTRL_COUNTS(ciput, nciput, countcheck) {		       \
901 		int i;							       \
902 		uint_t count = 0;					       \
903 		ASSERT((ciput) != NULL);				       \
904 		for (i = 0; i <= (nciput); i++) {			       \
905 			count += (((ciput)[i].ciputctrl_count) &	       \
906 			    SQ_FASTMASK);				       \
907 		}							       \
908 		ASSERT(count == (countcheck));				       \
909 	}
910 
911 #else	/* DEBUG */
912 
913 #define	SQ_PUTLOCKS_HELD(sq)
914 #define	SUMCHECK_SQ_PUTCOUNTS(sq, countcheck)
915 #define	SUMCHECK_CIPUTCTRL_COUNTS(sq, nciput, countcheck)
916 
917 #endif	/* DEBUG */
918 
919 #define	SUM_SQ_PUTCOUNTS(sq, count) {					       \
920 		if ((sq)->sq_ciputctrl != NULL) {			       \
921 			int i;						       \
922 			int ncounts = (sq)->sq_nciputctrl;		       \
923 			ciputctrl_t *cip = (sq)->sq_ciputctrl;		       \
924 			ASSERT((sq)->sq_type & SQ_CIPUT);		       \
925 			for (i = 0; i <= ncounts; i++) {		       \
926 				(count) += ((cip[i].ciputctrl_count) &	       \
927 				    SQ_FASTMASK);			       \
928 			}						       \
929 		}							       \
930 	}
931 
932 #define	CLAIM_QNEXT_LOCK(stp)	mutex_enter(&(stp)->sd_lock)
933 #define	RELEASE_QNEXT_LOCK(stp)	mutex_exit(&(stp)->sd_lock)
934 
935 /*
936  * syncq message manipulation macros.
937  */
938 /*
939  * Put a message on the queue syncq.
940  * Assumes QLOCK held.
941  */
942 #define	SQPUT_MP(qp, mp)						\
943 	{								\
944 		qp->q_syncqmsgs++;					\
945 		if (qp->q_sqhead == NULL) {				\
946 			qp->q_sqhead = qp->q_sqtail = mp;		\
947 		} else {						\
948 			qp->q_sqtail->b_next = mp;			\
949 			qp->q_sqtail = mp;				\
950 		}							\
951 	}
952 
953 /*
954  * Miscellaneous parameters and flags.
955  */
956 
957 /*
958  * Default timeout in milliseconds for ioctls and close
959  */
960 #define	STRTIMOUT 15000
961 
962 /*
963  * Flag values for stream io
964  */
965 #define	WRITEWAIT	0x1	/* waiting for write event */
966 #define	READWAIT	0x2	/* waiting for read event */
967 #define	NOINTR		0x4	/* error is not to be set for signal */
968 #define	GETWAIT		0x8	/* waiting for getmsg event */
969 
970 /*
971  * These flags need to be unique for stream io name space
972  * and copy modes name space.  These flags allow strwaitq
973  * and strdoioctl to proceed as if signals or errors on the stream
974  * head have not occurred; i.e. they will be detected by some other
975  * means.
976  * STR_NOSIG does not allow signals to interrupt the call
977  * STR_NOERROR does not allow stream head read, write or hup errors to
978  * affect the call.  When used with strdoioctl(), if a previous ioctl
979  * is pending and times out, STR_NOERROR will cause strdoioctl() to not
980  * return ETIME. If, however, the requested ioctl times out, ETIME
981  * will be returned (use ic_timout instead)
982  * STR_PEEK is used to inform strwaitq that the reader is peeking at data
983  * and that a non-persistent error should not be cleared.
984  * STR_DELAYERR is used to inform strwaitq that it should not check errors
985  * after being awoken since, in addition to an error, there might also be
986  * data queued on the stream head read queue.
987  */
988 #define	STR_NOSIG	0x10	/* Ignore signals during strdoioctl/strwaitq */
989 #define	STR_NOERROR	0x20	/* Ignore errors during strdoioctl/strwaitq */
990 #define	STR_PEEK	0x40	/* Peeking behavior on non-persistent errors */
991 #define	STR_DELAYERR	0x80	/* Do not check errors on return */
992 
993 /*
994  * Copy modes for tty and I_STR ioctls
995  */
996 #define	U_TO_K 	01			/* User to Kernel */
997 #define	K_TO_K  02			/* Kernel to Kernel */
998 
999 /*
1000  * Mux defines.
1001  */
1002 #define	LINKNORMAL	0x01		/* normal mux link */
1003 #define	LINKPERSIST	0x02		/* persistent mux link */
1004 #define	LINKTYPEMASK	0x03		/* bitmask of all link types */
1005 #define	LINKCLOSE	0x04		/* unlink from strclose */
1006 
1007 /*
1008  * Definitions of Streams macros and function interfaces.
1009  */
1010 
1011 /*
1012  * Obsolete queue scheduling macros. They are not used anymore, but still kept
1013  * here for 3-d party modules and drivers who might still use them.
1014  */
1015 #define	setqsched()
1016 #define	qready()	1
1017 
1018 #ifdef _KERNEL
1019 #define	runqueues()
1020 #define	queuerun()
1021 #endif
1022 
1023 /* compatibility module for style 2 drivers with DR race condition */
1024 #define	DRMODNAME	"drcompat"
1025 
1026 /*
1027  * Macros dealing with mux_nodes.
1028  */
1029 #define	MUX_VISIT(X)	((X)->mn_flags |= VISITED)
1030 #define	MUX_CLEAR(X)	((X)->mn_flags &= (~VISITED)); \
1031 			((X)->mn_originp = NULL)
1032 #define	MUX_DIDVISIT(X)	((X)->mn_flags & VISITED)
1033 
1034 
1035 /*
1036  * Twisted stream macros
1037  */
1038 #define	STRMATED(X)	((X)->sd_flag & STRMATE)
1039 #define	STRLOCKMATES(X)	if (&((X)->sd_lock) > &(((X)->sd_mate)->sd_lock)) { \
1040 				mutex_enter(&((X)->sd_lock)); \
1041 				mutex_enter(&(((X)->sd_mate)->sd_lock));  \
1042 			} else {  \
1043 				mutex_enter(&(((X)->sd_mate)->sd_lock)); \
1044 				mutex_enter(&((X)->sd_lock)); \
1045 			}
1046 #define	STRUNLOCKMATES(X)	mutex_exit(&((X)->sd_lock)); \
1047 			mutex_exit(&(((X)->sd_mate)->sd_lock))
1048 
1049 #ifdef _KERNEL
1050 
1051 extern void strinit(void);
1052 extern int strdoioctl(struct stdata *, struct strioctl *, int, int,
1053     cred_t *, int *);
1054 extern void strsendsig(struct strsig *, int, uchar_t, int);
1055 extern void str_sendsig(vnode_t *, int, uchar_t, int);
1056 extern void strhup(struct stdata *);
1057 extern int qattach(queue_t *, dev_t *, int, cred_t *, fmodsw_impl_t *,
1058     boolean_t);
1059 extern int qreopen(queue_t *, dev_t *, int, cred_t *);
1060 extern void qdetach(queue_t *, int, int, cred_t *, boolean_t);
1061 extern void enterq(queue_t *);
1062 extern void leaveq(queue_t *);
1063 extern int putiocd(mblk_t *, caddr_t, int, cred_t *);
1064 extern int getiocd(mblk_t *, caddr_t, int);
1065 extern struct linkinfo *alloclink(queue_t *, queue_t *, struct file *);
1066 extern void lbfree(struct linkinfo *);
1067 extern int linkcycle(stdata_t *, stdata_t *);
1068 extern struct linkinfo *findlinks(stdata_t *, int, int);
1069 extern queue_t *getendq(queue_t *);
1070 extern int mlink(vnode_t *, int, int, cred_t *, int *, int);
1071 extern int mlink_file(vnode_t *, int, struct file *, cred_t *, int *, int);
1072 extern int munlink(struct stdata *, struct linkinfo *, int, cred_t *, int *);
1073 extern int munlinkall(struct stdata *, int, cred_t *, int *);
1074 extern void mux_addedge(stdata_t *, stdata_t *, int);
1075 extern void mux_rmvedge(stdata_t *, int);
1076 extern int devflg_to_qflag(struct streamtab *, uint32_t, uint32_t *,
1077     uint32_t *);
1078 extern void setq(queue_t *, struct qinit *, struct qinit *, perdm_t *,
1079     uint32_t, uint32_t, boolean_t);
1080 extern perdm_t *hold_dm(struct streamtab *, uint32_t, uint32_t);
1081 extern void rele_dm(perdm_t *);
1082 extern int strmakectl(struct strbuf *, int32_t, int32_t, mblk_t **);
1083 extern int strmakedata(ssize_t *, struct uio *, stdata_t *, int32_t, mblk_t **);
1084 extern int strmakemsg(struct strbuf *, ssize_t *, struct uio *,
1085     struct stdata *, int32_t, mblk_t **);
1086 extern int strgetmsg(vnode_t *, struct strbuf *, struct strbuf *, uchar_t *,
1087     int *, int, rval_t *);
1088 extern int strputmsg(vnode_t *, struct strbuf *, struct strbuf *, uchar_t,
1089     int flag, int fmode);
1090 extern int strstartplumb(struct stdata *, int, int);
1091 extern void strendplumb(struct stdata *);
1092 extern int stropen(struct vnode *, dev_t *, int, cred_t *);
1093 extern int strclose(struct vnode *, int, cred_t *);
1094 extern int strpoll(register struct stdata *, short, int, short *,
1095     struct pollhead **);
1096 extern void strclean(struct vnode *);
1097 extern void str_cn_clean();	/* XXX hook for consoles signal cleanup */
1098 extern int strwrite(struct vnode *, struct uio *, cred_t *);
1099 extern int strread(struct vnode *, struct uio *, cred_t *);
1100 extern int strioctl(struct vnode *, int, intptr_t, int, int, cred_t *, int *);
1101 extern int strrput(queue_t *, mblk_t *);
1102 extern int strrput_nondata(queue_t *, mblk_t *);
1103 extern mblk_t *strrput_proto(vnode_t *, mblk_t *,
1104     strwakeup_t *, strsigset_t *, strsigset_t *, strpollset_t *);
1105 extern mblk_t *strrput_misc(vnode_t *, mblk_t *,
1106     strwakeup_t *, strsigset_t *, strsigset_t *, strpollset_t *);
1107 extern int getiocseqno(void);
1108 extern int strwaitbuf(size_t, int);
1109 extern int strwaitq(stdata_t *, int, ssize_t, int, clock_t, int *);
1110 extern void stralloctty(struct stdata *);
1111 extern void strfreectty(struct stdata *);
1112 extern struct stdata *shalloc(queue_t *);
1113 extern void shfree(struct stdata *s);
1114 extern queue_t *allocq(void);
1115 extern void freeq(queue_t *);
1116 extern qband_t *allocband(void);
1117 extern void freeband(qband_t *);
1118 extern void freebs_enqueue(mblk_t *, dblk_t *);
1119 extern void setqback(queue_t *, unsigned char);
1120 extern int strcopyin(void *, void *, size_t, int);
1121 extern int strcopyout(void *, void *, size_t, int);
1122 extern void strsignal(struct stdata *, int, int32_t);
1123 extern clock_t str_cv_wait(kcondvar_t *, kmutex_t *, clock_t, int);
1124 extern void disable_svc(queue_t *);
1125 extern void remove_runlist(queue_t *);
1126 extern void wait_svc(queue_t *);
1127 extern void backenable(queue_t *, uchar_t);
1128 extern void set_qend(queue_t *);
1129 extern int strgeterr(stdata_t *, int32_t, int);
1130 extern void qenable_locked(queue_t *);
1131 extern mblk_t *getq_noenab(queue_t *);
1132 extern void rmvq_noenab(queue_t *, mblk_t *);
1133 extern void qbackenable(queue_t *, uchar_t);
1134 
1135 extern void strblock(queue_t *);
1136 extern void strunblock(queue_t *);
1137 extern int qclaimed(queue_t *);
1138 extern int straccess(struct stdata *, enum jcaccess);
1139 
1140 extern void entersq(syncq_t *, int);
1141 extern void leavesq(syncq_t *, int);
1142 extern void claimq(queue_t *);
1143 extern void releaseq(queue_t *);
1144 extern void claimstr(queue_t *);
1145 extern void releasestr(queue_t *);
1146 extern void removeq(queue_t *);
1147 extern void insertq(struct stdata *, queue_t *);
1148 extern void drain_syncq(syncq_t *);
1149 extern void qfill_syncq(syncq_t *, queue_t *, mblk_t *);
1150 extern void qdrain_syncq(syncq_t *, queue_t *);
1151 extern int flush_syncq(syncq_t *, queue_t *);
1152 extern void wait_sq_svc(syncq_t *);
1153 
1154 extern void outer_enter(syncq_t *, uint16_t);
1155 extern void outer_exit(syncq_t *);
1156 extern void qwriter_inner(queue_t *, mblk_t *, void (*)());
1157 extern void qwriter_outer(queue_t *, mblk_t *, void (*)());
1158 
1159 extern callbparams_t *callbparams_alloc(syncq_t *, void (*)(void *),
1160     void *, int);
1161 extern void callbparams_free(syncq_t *, callbparams_t *);
1162 extern void callbparams_free_id(syncq_t *, callbparams_id_t, int32_t);
1163 extern void qcallbwrapper(void *);
1164 
1165 extern mblk_t *esballoc_wait(unsigned char *, size_t, uint_t, frtn_t *);
1166 extern mblk_t *esballoca(unsigned char *, size_t, uint_t, frtn_t *);
1167 extern mblk_t *desballoca(unsigned char *, size_t, uint_t, frtn_t *);
1168 extern int do_sendfp(struct stdata *, struct file *, struct cred *);
1169 extern int frozenstr(queue_t *);
1170 extern size_t xmsgsize(mblk_t *);
1171 
1172 extern void putnext_tail(syncq_t *, queue_t *, uint32_t);
1173 extern void stream_willservice(stdata_t *);
1174 extern void stream_runservice(stdata_t *);
1175 
1176 extern void strmate(vnode_t *, vnode_t *);
1177 extern queue_t *strvp2wq(vnode_t *);
1178 extern vnode_t *strq2vp(queue_t *);
1179 extern mblk_t *allocb_wait(size_t, uint_t, uint_t, int *);
1180 extern mblk_t *allocb_cred(size_t, cred_t *);
1181 extern mblk_t *allocb_cred_wait(size_t, uint_t, int *, cred_t *);
1182 extern mblk_t *allocb_tmpl(size_t, const mblk_t *);
1183 extern void mblk_setcred(mblk_t *, cred_t *);
1184 extern void strpollwakeup(vnode_t *, short);
1185 extern int putnextctl_wait(queue_t *, int);
1186 
1187 extern int kstrputmsg(struct vnode *, mblk_t *, struct uio *, ssize_t,
1188     unsigned char, int, int);
1189 extern int kstrgetmsg(struct vnode *, mblk_t **, struct uio *,
1190     unsigned char *, int *, clock_t, rval_t *);
1191 extern int kstrwritemp(struct vnode *, mblk_t *, ushort_t);
1192 
1193 extern void strsetrerror(vnode_t *, int, int, errfunc_t);
1194 extern void strsetwerror(vnode_t *, int, int, errfunc_t);
1195 extern void strseteof(vnode_t *, int);
1196 extern void strflushrq(vnode_t *, int);
1197 extern void strsetrputhooks(vnode_t *, uint_t, msgfunc_t, msgfunc_t);
1198 extern void strsetwputhooks(vnode_t *, uint_t, clock_t);
1199 extern int strwaitmark(vnode_t *);
1200 extern void strsignal_nolock(stdata_t *, int, int32_t);
1201 
1202 struct multidata_s;
1203 struct pdesc_s;
1204 extern int hcksum_assoc(mblk_t *, struct multidata_s *, struct pdesc_s  *,
1205     uint32_t, uint32_t, uint32_t, uint32_t, uint32_t, int);
1206 extern void hcksum_retrieve(mblk_t *, struct multidata_s *, struct pdesc_s *,
1207     uint32_t *, uint32_t *, uint32_t *, uint32_t *, uint32_t *);
1208 extern unsigned int bcksum(uchar_t *, int, unsigned int);
1209 extern boolean_t is_vmloaned_mblk(mblk_t *, struct multidata_s *,
1210     struct pdesc_s *);
1211 
1212 extern int fmodsw_register(const char *, struct streamtab *, int);
1213 extern int fmodsw_unregister(const char *);
1214 extern fmodsw_impl_t *fmodsw_find(const char *, fmodsw_flags_t);
1215 extern void fmodsw_rele(fmodsw_impl_t *);
1216 
1217 extern void freemsgchain(mblk_t *);
1218 extern mblk_t *copymsgchain(mblk_t *);
1219 
1220 /*
1221  * shared or externally configured data structures
1222  */
1223 extern ssize_t strmsgsz;		/* maximum stream message size */
1224 extern ssize_t strctlsz;		/* maximum size of ctl message */
1225 extern int nstrpush;			/* maximum number of pushes allowed */
1226 
1227 /*
1228  * Bufcalls related variables.
1229  */
1230 extern struct bclist strbcalls;		/* List of bufcalls */
1231 extern kmutex_t	strbcall_lock;		/* Protects the list of bufcalls */
1232 extern kcondvar_t strbcall_cv;		/* Signaling when a bufcall is added */
1233 extern kcondvar_t bcall_cv;	/* wait of executing bufcall completes */
1234 
1235 extern frtn_t frnop;
1236 
1237 extern struct kmem_cache *ciputctrl_cache;
1238 extern int n_ciputctrl;
1239 extern int max_n_ciputctrl;
1240 extern int min_n_ciputctrl;
1241 
1242 extern cdevsw_impl_t *devimpl;
1243 #endif	/* _KERNEL */
1244 
1245 /*
1246  * Note: Use of these macros are restricted to kernel/unix and
1247  * intended for the STREAMS framework.
1248  * All modules/drivers should include sys/ddi.h.
1249  *
1250  * Finding related queues
1251  */
1252 #define		_OTHERQ(q)	((q)->q_flag&QREADR? (q)+1: (q)-1)
1253 #define		_WR(q)		((q)->q_flag&QREADR? (q)+1: (q))
1254 #define		_RD(q)		((q)->q_flag&QREADR? (q): (q)-1)
1255 #define		_SAMESTR(q)	(!((q)->q_flag & QEND))
1256 
1257 /*
1258  * These are also declared here for modules/drivers that erroneously
1259  * include strsubr.h after ddi.h or fail to include ddi.h at all.
1260  */
1261 extern struct queue *OTHERQ(queue_t *); /* stream.h */
1262 extern struct queue *RD(queue_t *);
1263 extern struct queue *WR(queue_t *);
1264 extern int SAMESTR(queue_t *);
1265 
1266 #ifdef	__cplusplus
1267 }
1268 #endif
1269 
1270 
1271 #endif	/* _SYS_STRSUBR_H */
1272