xref: /linux/arch/powerpc/platforms/cell/spufs/context.c (revision 643d1f7fe3aa12c8bdea6fa5b4ba874ff6dd601d)
1 /*
2  * SPU file system -- SPU context management
3  *
4  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
5  *
6  * Author: Arnd Bergmann <arndb@de.ibm.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2, or (at your option)
11  * any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/fs.h>
24 #include <linux/mm.h>
25 #include <linux/module.h>
26 #include <linux/slab.h>
27 #include <asm/atomic.h>
28 #include <asm/spu.h>
29 #include <asm/spu_csa.h>
30 #include "spufs.h"
31 
32 
33 atomic_t nr_spu_contexts = ATOMIC_INIT(0);
34 
35 struct spu_context *alloc_spu_context(struct spu_gang *gang)
36 {
37 	struct spu_context *ctx;
38 	ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
39 	if (!ctx)
40 		goto out;
41 	/* Binding to physical processor deferred
42 	 * until spu_activate().
43 	 */
44 	if (spu_init_csa(&ctx->csa))
45 		goto out_free;
46 	spin_lock_init(&ctx->mmio_lock);
47 	mutex_init(&ctx->mapping_lock);
48 	kref_init(&ctx->kref);
49 	mutex_init(&ctx->state_mutex);
50 	mutex_init(&ctx->run_mutex);
51 	init_waitqueue_head(&ctx->ibox_wq);
52 	init_waitqueue_head(&ctx->wbox_wq);
53 	init_waitqueue_head(&ctx->stop_wq);
54 	init_waitqueue_head(&ctx->mfc_wq);
55 	init_waitqueue_head(&ctx->run_wq);
56 	ctx->state = SPU_STATE_SAVED;
57 	ctx->ops = &spu_backing_ops;
58 	ctx->owner = get_task_mm(current);
59 	INIT_LIST_HEAD(&ctx->rq);
60 	INIT_LIST_HEAD(&ctx->aff_list);
61 	if (gang)
62 		spu_gang_add_ctx(gang, ctx);
63 
64 	__spu_update_sched_info(ctx);
65 	spu_set_timeslice(ctx);
66 	ctx->stats.util_state = SPU_UTIL_IDLE_LOADED;
67 
68 	atomic_inc(&nr_spu_contexts);
69 	goto out;
70 out_free:
71 	kfree(ctx);
72 	ctx = NULL;
73 out:
74 	return ctx;
75 }
76 
77 void destroy_spu_context(struct kref *kref)
78 {
79 	struct spu_context *ctx;
80 	ctx = container_of(kref, struct spu_context, kref);
81 	mutex_lock(&ctx->state_mutex);
82 	spu_deactivate(ctx);
83 	mutex_unlock(&ctx->state_mutex);
84 	spu_fini_csa(&ctx->csa);
85 	if (ctx->gang)
86 		spu_gang_remove_ctx(ctx->gang, ctx);
87 	if (ctx->prof_priv_kref)
88 		kref_put(ctx->prof_priv_kref, ctx->prof_priv_release);
89 	BUG_ON(!list_empty(&ctx->rq));
90 	atomic_dec(&nr_spu_contexts);
91 	kfree(ctx);
92 }
93 
94 struct spu_context * get_spu_context(struct spu_context *ctx)
95 {
96 	kref_get(&ctx->kref);
97 	return ctx;
98 }
99 
100 int put_spu_context(struct spu_context *ctx)
101 {
102 	return kref_put(&ctx->kref, &destroy_spu_context);
103 }
104 
105 /* give up the mm reference when the context is about to be destroyed */
106 void spu_forget(struct spu_context *ctx)
107 {
108 	struct mm_struct *mm;
109 
110 	/*
111 	 * This is basically an open-coded spu_acquire_saved, except that
112 	 * we don't acquire the state mutex interruptible.
113 	 */
114 	mutex_lock(&ctx->state_mutex);
115 	if (ctx->state != SPU_STATE_SAVED) {
116 		set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
117 		spu_deactivate(ctx);
118 	}
119 
120 	mm = ctx->owner;
121 	ctx->owner = NULL;
122 	mmput(mm);
123 	spu_release(ctx);
124 }
125 
126 void spu_unmap_mappings(struct spu_context *ctx)
127 {
128 	mutex_lock(&ctx->mapping_lock);
129 	if (ctx->local_store)
130 		unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
131 	if (ctx->mfc)
132 		unmap_mapping_range(ctx->mfc, 0, 0x1000, 1);
133 	if (ctx->cntl)
134 		unmap_mapping_range(ctx->cntl, 0, 0x1000, 1);
135 	if (ctx->signal1)
136 		unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1);
137 	if (ctx->signal2)
138 		unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1);
139 	if (ctx->mss)
140 		unmap_mapping_range(ctx->mss, 0, 0x1000, 1);
141 	if (ctx->psmap)
142 		unmap_mapping_range(ctx->psmap, 0, 0x20000, 1);
143 	mutex_unlock(&ctx->mapping_lock);
144 }
145 
146 /**
147  * spu_acquire_saved - lock spu contex and make sure it is in saved state
148  * @ctx:	spu contex to lock
149  */
150 int spu_acquire_saved(struct spu_context *ctx)
151 {
152 	int ret;
153 
154 	ret = spu_acquire(ctx);
155 	if (ret)
156 		return ret;
157 
158 	if (ctx->state != SPU_STATE_SAVED) {
159 		set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
160 		spu_deactivate(ctx);
161 	}
162 
163 	return 0;
164 }
165 
166 /**
167  * spu_release_saved - unlock spu context and return it to the runqueue
168  * @ctx:	context to unlock
169  */
170 void spu_release_saved(struct spu_context *ctx)
171 {
172 	BUG_ON(ctx->state != SPU_STATE_SAVED);
173 
174 	if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags))
175 		spu_activate(ctx, 0);
176 
177 	spu_release(ctx);
178 }
179 
180