1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate * CDDL HEADER START
3*7c478bd9Sstevel@tonic-gate *
4*7c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*7c478bd9Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*7c478bd9Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*7c478bd9Sstevel@tonic-gate * with the License.
8*7c478bd9Sstevel@tonic-gate *
9*7c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*7c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*7c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions
12*7c478bd9Sstevel@tonic-gate * and limitations under the License.
13*7c478bd9Sstevel@tonic-gate *
14*7c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*7c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*7c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*7c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*7c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*7c478bd9Sstevel@tonic-gate *
20*7c478bd9Sstevel@tonic-gate * CDDL HEADER END
21*7c478bd9Sstevel@tonic-gate */
22*7c478bd9Sstevel@tonic-gate /*
23*7c478bd9Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
24*7c478bd9Sstevel@tonic-gate * Use is subject to license terms.
25*7c478bd9Sstevel@tonic-gate */
26*7c478bd9Sstevel@tonic-gate
27*7c478bd9Sstevel@tonic-gate #include <sys/types.h>
28*7c478bd9Sstevel@tonic-gate #include <sys/kmem.h>
29*7c478bd9Sstevel@tonic-gate #include <sys/bitmap.h>
30*7c478bd9Sstevel@tonic-gate #include <sys/stream.h>
31*7c478bd9Sstevel@tonic-gate #include <sys/strsubr.h>
32*7c478bd9Sstevel@tonic-gate #define _SUN_TPI_VERSION 2
33*7c478bd9Sstevel@tonic-gate #include <sys/tihdr.h>
34*7c478bd9Sstevel@tonic-gate #include <sys/suntpi.h>
35*7c478bd9Sstevel@tonic-gate
36*7c478bd9Sstevel@tonic-gate /*
37*7c478bd9Sstevel@tonic-gate * Hash table parameters for tpi_provinfo_table.
38*7c478bd9Sstevel@tonic-gate */
39*7c478bd9Sstevel@tonic-gate #define TPI_HASH_BITS 4
40*7c478bd9Sstevel@tonic-gate #define TPI_NHASH (1 << TPI_HASH_BITS)
41*7c478bd9Sstevel@tonic-gate
42*7c478bd9Sstevel@tonic-gate /*
43*7c478bd9Sstevel@tonic-gate * Use the first element in the key for the hash.
44*7c478bd9Sstevel@tonic-gate */
45*7c478bd9Sstevel@tonic-gate #define TPI_HASH(p) ((((uintptr_t *)p)[0] >> tpi_hashshift) % TPI_NHASH)
46*7c478bd9Sstevel@tonic-gate /*
47*7c478bd9Sstevel@tonic-gate * SAMESTR is a very confusing name. LAST_QUEUE is introduced for readability.
48*7c478bd9Sstevel@tonic-gate */
49*7c478bd9Sstevel@tonic-gate #define LAST_QUEUE(q) (!SAMESTR(q))
50*7c478bd9Sstevel@tonic-gate
51*7c478bd9Sstevel@tonic-gate static tpi_provinfo_t *tpi_provinfo_table[TPI_NHASH];
52*7c478bd9Sstevel@tonic-gate static kmutex_t tpi_provinfo_lock;
53*7c478bd9Sstevel@tonic-gate static int tpi_hashshift;
54*7c478bd9Sstevel@tonic-gate
55*7c478bd9Sstevel@tonic-gate /*
56*7c478bd9Sstevel@tonic-gate * In most cases there is some transport provider (like tcp or udp) below
57*7c478bd9Sstevel@tonic-gate * transport user (like timod or sockets). However, it is possible to construct
58*7c478bd9Sstevel@tonic-gate * stream without transport provider (e.g. by pushing timod into FIFO). It is
59*7c478bd9Sstevel@tonic-gate * hardly of any use, but this condition was observed with sparcv9 abi tests.
60*7c478bd9Sstevel@tonic-gate * To count for such special case, a special tpi_nullprov static data is
61*7c478bd9Sstevel@tonic-gate * provided to cache information about such degenerated null-transport case.
62*7c478bd9Sstevel@tonic-gate */
63*7c478bd9Sstevel@tonic-gate static tpi_provinfo_t tpi_nullprov; /* Placeholder for null transport */
64*7c478bd9Sstevel@tonic-gate
65*7c478bd9Sstevel@tonic-gate /*
66*7c478bd9Sstevel@tonic-gate * Initialise the TPI support routines. Called from strinit().
67*7c478bd9Sstevel@tonic-gate */
68*7c478bd9Sstevel@tonic-gate void
tpi_init()69*7c478bd9Sstevel@tonic-gate tpi_init()
70*7c478bd9Sstevel@tonic-gate {
71*7c478bd9Sstevel@tonic-gate mutex_init(&tpi_provinfo_lock, NULL, MUTEX_DEFAULT, NULL);
72*7c478bd9Sstevel@tonic-gate
73*7c478bd9Sstevel@tonic-gate /*
74*7c478bd9Sstevel@tonic-gate * Calculate the right shift for hashing a tpi_provinfo_t.
75*7c478bd9Sstevel@tonic-gate */
76*7c478bd9Sstevel@tonic-gate tpi_hashshift = highbit(sizeof (tpi_provinfo_t));
77*7c478bd9Sstevel@tonic-gate }
78*7c478bd9Sstevel@tonic-gate
79*7c478bd9Sstevel@tonic-gate /*
80*7c478bd9Sstevel@tonic-gate * Generate a downstream signature given the write-side queue. It
81*7c478bd9Sstevel@tonic-gate * passes back the size of the generated key in *keylenp. This routine
82*7c478bd9Sstevel@tonic-gate * cannot multithread as it returns a pointer to a static data item.
83*7c478bd9Sstevel@tonic-gate *
84*7c478bd9Sstevel@tonic-gate * There is no way (in the current module loading infrastructure) to
85*7c478bd9Sstevel@tonic-gate * _absolutely_ guarantee that the key below uniquely identifies an
86*7c478bd9Sstevel@tonic-gate * arrangement of modules and drivers. A module _might_ be unloaded and
87*7c478bd9Sstevel@tonic-gate * another module _might_ be loaded such that the qi_minfo is at _exactly_
88*7c478bd9Sstevel@tonic-gate * same kernel address, and then it _might_ be placed in a transport
89*7c478bd9Sstevel@tonic-gate * provider stream in exactly the same configuration (modules above and
90*7c478bd9Sstevel@tonic-gate * below all identical) - but it would take quite a few coincidences
91*7c478bd9Sstevel@tonic-gate * and modules loading and unloading does not usually happen n times a
92*7c478bd9Sstevel@tonic-gate * second...
93*7c478bd9Sstevel@tonic-gate */
94*7c478bd9Sstevel@tonic-gate static void *
tpi_makekey(queue_t * q,size_t * keylenp)95*7c478bd9Sstevel@tonic-gate tpi_makekey(queue_t *q, size_t *keylenp)
96*7c478bd9Sstevel@tonic-gate {
97*7c478bd9Sstevel@tonic-gate static uintptr_t *key = NULL;
98*7c478bd9Sstevel@tonic-gate int i;
99*7c478bd9Sstevel@tonic-gate
100*7c478bd9Sstevel@tonic-gate ASSERT(q != NULL);
101*7c478bd9Sstevel@tonic-gate ASSERT(MUTEX_HELD(&tpi_provinfo_lock));
102*7c478bd9Sstevel@tonic-gate
103*7c478bd9Sstevel@tonic-gate /* assert this queue is write queue and qprocson() is called before */
104*7c478bd9Sstevel@tonic-gate ASSERT((q->q_flag & QREADR) == 0);
105*7c478bd9Sstevel@tonic-gate ASSERT(q->q_next != NULL);
106*7c478bd9Sstevel@tonic-gate
107*7c478bd9Sstevel@tonic-gate /*
108*7c478bd9Sstevel@tonic-gate * This can be global because tpi_makekey is called with
109*7c478bd9Sstevel@tonic-gate * tpi_provinfo_lock.
110*7c478bd9Sstevel@tonic-gate */
111*7c478bd9Sstevel@tonic-gate if (key == NULL)
112*7c478bd9Sstevel@tonic-gate key = kmem_alloc((nstrpush + 1) * sizeof (uintptr_t), KM_SLEEP);
113*7c478bd9Sstevel@tonic-gate
114*7c478bd9Sstevel@tonic-gate ASSERT(key != NULL);
115*7c478bd9Sstevel@tonic-gate
116*7c478bd9Sstevel@tonic-gate /*
117*7c478bd9Sstevel@tonic-gate * Go down q_next to the driver, but no further. We use the qi_minfo
118*7c478bd9Sstevel@tonic-gate * because we can find in from the queue and it is a stable part of
119*7c478bd9Sstevel@tonic-gate * any driver/module infrastructure.
120*7c478bd9Sstevel@tonic-gate */
121*7c478bd9Sstevel@tonic-gate for (i = 0; !LAST_QUEUE(q) && (q = q->q_next) != NULL; ++i) {
122*7c478bd9Sstevel@tonic-gate ASSERT(i < nstrpush + 1);
123*7c478bd9Sstevel@tonic-gate key[i] = (uintptr_t)q->q_qinfo->qi_minfo;
124*7c478bd9Sstevel@tonic-gate }
125*7c478bd9Sstevel@tonic-gate
126*7c478bd9Sstevel@tonic-gate /*
127*7c478bd9Sstevel@tonic-gate * Allocate the actual key with the proper length, and pass it
128*7c478bd9Sstevel@tonic-gate * all back.
129*7c478bd9Sstevel@tonic-gate */
130*7c478bd9Sstevel@tonic-gate *keylenp = i * sizeof (uintptr_t);
131*7c478bd9Sstevel@tonic-gate return ((void *)key);
132*7c478bd9Sstevel@tonic-gate }
133*7c478bd9Sstevel@tonic-gate
134*7c478bd9Sstevel@tonic-gate /*
135*7c478bd9Sstevel@tonic-gate * Find an existing provider entry given a queue pointer, or allocate a
136*7c478bd9Sstevel@tonic-gate * new empty entry if not found. Because this routine calls kmem_alloc
137*7c478bd9Sstevel@tonic-gate * with KM_SLEEP, and because it traverses the q_next pointers of a stream
138*7c478bd9Sstevel@tonic-gate * it must be called with a proper user context and within a perimeter
139*7c478bd9Sstevel@tonic-gate * which protects the STREAM e.g. an open routine. This routine always
140*7c478bd9Sstevel@tonic-gate * returns a valid pointer.
141*7c478bd9Sstevel@tonic-gate */
142*7c478bd9Sstevel@tonic-gate tpi_provinfo_t *
tpi_findprov(queue_t * q)143*7c478bd9Sstevel@tonic-gate tpi_findprov(queue_t *q)
144*7c478bd9Sstevel@tonic-gate {
145*7c478bd9Sstevel@tonic-gate void *key;
146*7c478bd9Sstevel@tonic-gate size_t keylen;
147*7c478bd9Sstevel@tonic-gate tpi_provinfo_t **tpp;
148*7c478bd9Sstevel@tonic-gate
149*7c478bd9Sstevel@tonic-gate mutex_enter(&tpi_provinfo_lock);
150*7c478bd9Sstevel@tonic-gate
151*7c478bd9Sstevel@tonic-gate /*
152*7c478bd9Sstevel@tonic-gate * Must hold tpi_provinfo_lock since tpi_makekey() returns a pointer
153*7c478bd9Sstevel@tonic-gate * to static data.
154*7c478bd9Sstevel@tonic-gate */
155*7c478bd9Sstevel@tonic-gate key = tpi_makekey(WR(q), &keylen);
156*7c478bd9Sstevel@tonic-gate
157*7c478bd9Sstevel@tonic-gate if (keylen == 0) {
158*7c478bd9Sstevel@tonic-gate /* there is nothing below us, return special nullprov entry */
159*7c478bd9Sstevel@tonic-gate mutex_exit(&tpi_provinfo_lock);
160*7c478bd9Sstevel@tonic-gate return (&tpi_nullprov);
161*7c478bd9Sstevel@tonic-gate }
162*7c478bd9Sstevel@tonic-gate
163*7c478bd9Sstevel@tonic-gate /*
164*7c478bd9Sstevel@tonic-gate * Look for an existing entry, or the place to put a new one.
165*7c478bd9Sstevel@tonic-gate */
166*7c478bd9Sstevel@tonic-gate for (tpp = &tpi_provinfo_table[TPI_HASH(key)]; *tpp != NULL;
167*7c478bd9Sstevel@tonic-gate tpp = &(*tpp)->tpi_next) {
168*7c478bd9Sstevel@tonic-gate if ((*tpp)->tpi_keylen == keylen &&
169*7c478bd9Sstevel@tonic-gate bcmp((*tpp)->tpi_key, key, keylen) == 0) {
170*7c478bd9Sstevel@tonic-gate mutex_exit(&tpi_provinfo_lock);
171*7c478bd9Sstevel@tonic-gate return (*tpp);
172*7c478bd9Sstevel@tonic-gate }
173*7c478bd9Sstevel@tonic-gate }
174*7c478bd9Sstevel@tonic-gate
175*7c478bd9Sstevel@tonic-gate /*
176*7c478bd9Sstevel@tonic-gate * Allocate and fill in the new tpi_provinfo_t.
177*7c478bd9Sstevel@tonic-gate */
178*7c478bd9Sstevel@tonic-gate *tpp = kmem_zalloc(sizeof (tpi_provinfo_t), KM_SLEEP);
179*7c478bd9Sstevel@tonic-gate (*tpp)->tpi_key = kmem_alloc(keylen, KM_SLEEP);
180*7c478bd9Sstevel@tonic-gate bcopy(key, (*tpp)->tpi_key, keylen);
181*7c478bd9Sstevel@tonic-gate (*tpp)->tpi_keylen = keylen;
182*7c478bd9Sstevel@tonic-gate mutex_init(&(*tpp)->tpi_lock, NULL, MUTEX_DEFAULT, NULL);
183*7c478bd9Sstevel@tonic-gate
184*7c478bd9Sstevel@tonic-gate mutex_exit(&tpi_provinfo_lock);
185*7c478bd9Sstevel@tonic-gate return (*tpp);
186*7c478bd9Sstevel@tonic-gate }
187*7c478bd9Sstevel@tonic-gate
188*7c478bd9Sstevel@tonic-gate /*
189*7c478bd9Sstevel@tonic-gate * Allocate a TPI ACK reusing the old message if possible.
190*7c478bd9Sstevel@tonic-gate */
191*7c478bd9Sstevel@tonic-gate mblk_t *
tpi_ack_alloc(mblk_t * mp,size_t size,uchar_t db_type,t_scalar_t prim)192*7c478bd9Sstevel@tonic-gate tpi_ack_alloc(mblk_t *mp, size_t size, uchar_t db_type, t_scalar_t prim)
193*7c478bd9Sstevel@tonic-gate {
194*7c478bd9Sstevel@tonic-gate mblk_t *omp = mp;
195*7c478bd9Sstevel@tonic-gate
196*7c478bd9Sstevel@tonic-gate if ((mp = reallocb(mp, size, 0)) == NULL) {
197*7c478bd9Sstevel@tonic-gate freemsg(omp);
198*7c478bd9Sstevel@tonic-gate return (NULL);
199*7c478bd9Sstevel@tonic-gate }
200*7c478bd9Sstevel@tonic-gate if (mp->b_cont != NULL) {
201*7c478bd9Sstevel@tonic-gate freemsg(mp->b_cont);
202*7c478bd9Sstevel@tonic-gate mp->b_cont = NULL;
203*7c478bd9Sstevel@tonic-gate }
204*7c478bd9Sstevel@tonic-gate mp->b_datap->db_type = db_type;
205*7c478bd9Sstevel@tonic-gate mp->b_wptr = mp->b_rptr + size;
206*7c478bd9Sstevel@tonic-gate ((union T_primitives *)mp->b_rptr)->type = prim;
207*7c478bd9Sstevel@tonic-gate return (mp);
208*7c478bd9Sstevel@tonic-gate }
209