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/*
23 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29
30#include <sys/types.h>
31#include <sys/cmn_err.h>
32#include <sys/mman.h>
33#include <vm/hat_sfmmu.h>
34#include <vm/xhat.h>
35#include <vm/xhat_sfmmu.h>
36#include <vm/page.h>
37#include <vm/as.h>
38
39
40
41/*
42 * Allocates a block that includes both struct xhat and
43 * provider-specific data.
44 */
45struct xhat_hme_blk *
46xhat_alloc_xhatblk(struct xhat *xhat)
47{
48	struct xhat_hme_blk *xblk;
49	xblk_cache_t	*xblkcache = xhat->xhat_provider->xblkcache;
50
51
52
53	mutex_enter(&xblkcache->lock);
54	if (xblkcache->free_blks) {
55		xblk = (struct xhat_hme_blk *)
56		    sfmmu_hmetohblk(xblkcache->free_blks);
57
58		/*
59		 * Since we are always walking the list in the
60		 * forward direction, we don't update prev pointers
61		 */
62		xblkcache->free_blks = xblk->xblk_hme[0].hme_next;
63		mutex_exit(&xblkcache->lock);
64	} else {
65		mutex_exit(&xblkcache->lock);
66		xblk = kmem_cache_alloc(xblkcache->cache, KM_SLEEP);
67	}
68
69	return (xblk);
70}
71
72
73/*
74 * Return the block to free_blks pool. The memory will
75 * be freed in the reclaim routine.
76 */
77void
78xhat_free_xhatblk(struct xhat_hme_blk *xblk)
79{
80	xblk_cache_t	*xblkcache = xblk->xhat_hme_blk_hat->
81	    xhat_provider->xblkcache;
82
83
84	mutex_enter(&xblkcache->lock);
85	xblk->xblk_hme[0].hme_next = xblkcache->free_blks;
86	xblkcache->free_blks = &xblk->xblk_hme[0];
87	mutex_exit(&xblkcache->lock);
88}
89
90
91/*
92 * Ran by kmem reaper thread. Also called when
93 * provider unregisters
94 */
95void
96xhat_xblkcache_reclaim(void *arg)
97{
98	xhat_provider_t *provider = (xhat_provider_t *)arg;
99	struct sf_hment	*sfhme;
100	struct xhat_hme_blk	*xblk;
101	xblk_cache_t	*xblkcache;
102
103	if (provider == NULL)
104		cmn_err(CE_PANIC, "xhat_xblkcache_reclaim() is passed NULL");
105
106	xblkcache = provider->xblkcache;
107
108
109	while (xblkcache->free_blks != NULL) {
110
111		/*
112		 * Put free blocks on a separate list
113		 * and free free_blks pointer.
114		 */
115		mutex_enter(&xblkcache->lock);
116		sfhme = xblkcache->free_blks;
117		xblkcache->free_blks = NULL;
118		mutex_exit(&xblkcache->lock);
119
120		while (sfhme != NULL) {
121			xblk = (struct xhat_hme_blk *)sfmmu_hmetohblk(sfhme);
122			ASSERT(xblk->xhat_hme_blk_misc.xhat_bit == 1);
123			sfhme = sfhme->hme_next;
124			kmem_cache_free(xblkcache->cache, xblk);
125		}
126	}
127}
128
129
130
131
132/*
133 * Insert the xhat block (or, more precisely, the sf_hment)
134 * into page's p_mapping list.
135 */
136pfn_t
137xhat_insert_xhatblk(page_t *pp, struct xhat *xhat, void **blk)
138{
139	kmutex_t *pml;
140	pfn_t pfn;
141	struct xhat_hme_blk *xblk;
142
143
144
145	xblk = xhat_alloc_xhatblk(xhat);
146	if (xblk == NULL)
147		return (0);
148
149	/* Add a "user" to the XHAT */
150	xhat_hat_hold(xhat);
151
152	xblk->xhat_hme_blk_hat = xhat;
153	xblk->xhat_hme_blk_misc.xhat_bit = 1;
154
155	pml = sfmmu_mlist_enter(pp);
156
157
158	/* Insert at the head of p_mapping list */
159	xblk->xblk_hme[0].hme_prev = NULL;
160	xblk->xblk_hme[0].hme_next = pp->p_mapping;
161	xblk->xblk_hme[0].hme_page = pp;
162
163	/* Only one tte per xhat_hme_blk, at least for now */
164	xblk->xblk_hme[0].hme_tte.tte_hmenum = 0;
165
166	if (pp->p_mapping) {
167		((struct sf_hment *)(pp->p_mapping))->hme_prev =
168		    &(xblk->xblk_hme[0]);
169		ASSERT(pp->p_share > 0);
170	} else	{
171		/* EMPTY */
172		ASSERT(pp->p_share == 0);
173	}
174	pp->p_mapping = &(xblk->xblk_hme[0]);
175
176	/*
177	 * Update number of mappings.
178	 */
179	pp->p_share++;
180	pfn = pp->p_pagenum;
181
182	sfmmu_mlist_exit(pml);
183
184	*blk = XBLK2PROVBLK(xblk);
185
186	return (pfn);
187}
188
189
190/*
191 * mlist_locked indicates whether the mapping list
192 * is locked. If provider did not lock it himself, the
193 * only time it is locked in HAT layer is in
194 * hat_pageunload().
195 */
196int
197xhat_delete_xhatblk(void *blk, int mlist_locked)
198{
199	struct xhat_hme_blk *xblk = PROVBLK2XBLK(blk);
200	page_t *pp = xblk->xblk_hme[0].hme_page;
201	kmutex_t *pml;
202
203
204	ASSERT(pp != NULL);
205	ASSERT(pp->p_share > 0);
206
207	if (!mlist_locked)
208		pml = sfmmu_mlist_enter(pp);
209	else
210		ASSERT(sfmmu_mlist_held(pp));
211
212	pp->p_share--;
213
214	if (xblk->xblk_hme[0].hme_prev) {
215		ASSERT(pp->p_mapping != &(xblk->xblk_hme[0]));
216		ASSERT(xblk->xblk_hme[0].hme_prev->hme_page == pp);
217		xblk->xblk_hme[0].hme_prev->hme_next =
218		    xblk->xblk_hme[0].hme_next;
219	} else {
220		ASSERT(pp->p_mapping == &(xblk->xblk_hme[0]));
221		pp->p_mapping = xblk->xblk_hme[0].hme_next;
222		ASSERT((pp->p_mapping == NULL) ?
223			(pp->p_share == 0) : 1);
224	}
225
226	if (xblk->xblk_hme->hme_next) {
227		ASSERT(xblk->xblk_hme[0].hme_next->hme_page == pp);
228		xblk->xblk_hme[0].hme_next->hme_prev =
229		    xblk->xblk_hme[0].hme_prev;
230	}
231
232	if (!mlist_locked)
233		sfmmu_mlist_exit(pml);
234
235	xhat_hat_rele(xblk->xhat_hme_blk_hat);
236	xhat_free_xhatblk(xblk);
237
238
239	return (0);
240}
241