xref: /openbmc/linux/arch/powerpc/platforms/cell/spufs/context.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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 	ctx->state = SPU_STATE_SAVED;
56 	ctx->ops = &spu_backing_ops;
57 	ctx->owner = get_task_mm(current);
58 	INIT_LIST_HEAD(&ctx->rq);
59 	INIT_LIST_HEAD(&ctx->aff_list);
60 	if (gang)
61 		spu_gang_add_ctx(gang, ctx);
62 
63 	__spu_update_sched_info(ctx);
64 	spu_set_timeslice(ctx);
65 	ctx->stats.util_state = SPU_UTIL_IDLE_LOADED;
66 
67 	atomic_inc(&nr_spu_contexts);
68 	goto out;
69 out_free:
70 	kfree(ctx);
71 	ctx = NULL;
72 out:
73 	return ctx;
74 }
75 
76 void destroy_spu_context(struct kref *kref)
77 {
78 	struct spu_context *ctx;
79 	ctx = container_of(kref, struct spu_context, kref);
80 	mutex_lock(&ctx->state_mutex);
81 	spu_deactivate(ctx);
82 	mutex_unlock(&ctx->state_mutex);
83 	spu_fini_csa(&ctx->csa);
84 	if (ctx->gang)
85 		spu_gang_remove_ctx(ctx->gang, ctx);
86 	if (ctx->prof_priv_kref)
87 		kref_put(ctx->prof_priv_kref, ctx->prof_priv_release);
88 	BUG_ON(!list_empty(&ctx->rq));
89 	atomic_dec(&nr_spu_contexts);
90 	kfree(ctx);
91 }
92 
93 struct spu_context * get_spu_context(struct spu_context *ctx)
94 {
95 	kref_get(&ctx->kref);
96 	return ctx;
97 }
98 
99 int put_spu_context(struct spu_context *ctx)
100 {
101 	return kref_put(&ctx->kref, &destroy_spu_context);
102 }
103 
104 /* give up the mm reference when the context is about to be destroyed */
105 void spu_forget(struct spu_context *ctx)
106 {
107 	struct mm_struct *mm;
108 	spu_acquire_saved(ctx);
109 	mm = ctx->owner;
110 	ctx->owner = NULL;
111 	mmput(mm);
112 	spu_release(ctx);
113 }
114 
115 void spu_unmap_mappings(struct spu_context *ctx)
116 {
117 	mutex_lock(&ctx->mapping_lock);
118 	if (ctx->local_store)
119 		unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
120 	if (ctx->mfc)
121 		unmap_mapping_range(ctx->mfc, 0, 0x1000, 1);
122 	if (ctx->cntl)
123 		unmap_mapping_range(ctx->cntl, 0, 0x1000, 1);
124 	if (ctx->signal1)
125 		unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1);
126 	if (ctx->signal2)
127 		unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1);
128 	if (ctx->mss)
129 		unmap_mapping_range(ctx->mss, 0, 0x1000, 1);
130 	if (ctx->psmap)
131 		unmap_mapping_range(ctx->psmap, 0, 0x20000, 1);
132 	mutex_unlock(&ctx->mapping_lock);
133 }
134 
135 /**
136  * spu_acquire_runnable - lock spu contex and make sure it is in runnable state
137  * @ctx:	spu contex to lock
138  *
139  * Note:
140  *	Returns 0 and with the context locked on success
141  *	Returns negative error and with the context _unlocked_ on failure.
142  */
143 int spu_acquire_runnable(struct spu_context *ctx, unsigned long flags)
144 {
145 	int ret = -EINVAL;
146 
147 	spu_acquire(ctx);
148 	if (ctx->state == SPU_STATE_SAVED) {
149 		/*
150 		 * Context is about to be freed, so we can't acquire it anymore.
151 		 */
152 		if (!ctx->owner)
153 			goto out_unlock;
154 		ret = spu_activate(ctx, flags);
155 		if (ret)
156 			goto out_unlock;
157 	}
158 
159 	return 0;
160 
161  out_unlock:
162 	spu_release(ctx);
163 	return ret;
164 }
165 
166 /**
167  * spu_acquire_saved - lock spu contex and make sure it is in saved state
168  * @ctx:	spu contex to lock
169  */
170 void spu_acquire_saved(struct spu_context *ctx)
171 {
172 	spu_acquire(ctx);
173 	if (ctx->state != SPU_STATE_SAVED) {
174 		set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
175 		spu_deactivate(ctx);
176 	}
177 }
178 
179 /**
180  * spu_release_saved - unlock spu context and return it to the runqueue
181  * @ctx:	context to unlock
182  */
183 void spu_release_saved(struct spu_context *ctx)
184 {
185 	BUG_ON(ctx->state != SPU_STATE_SAVED);
186 
187 	if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags))
188 		spu_activate(ctx, 0);
189 
190 	spu_release(ctx);
191 }
192 
193 void spu_set_profile_private_kref(struct spu_context *ctx,
194 				  struct kref *prof_info_kref,
195 				  void ( * prof_info_release) (struct kref *kref))
196 {
197 	ctx->prof_priv_kref = prof_info_kref;
198 	ctx->prof_priv_release = prof_info_release;
199 }
200 EXPORT_SYMBOL_GPL(spu_set_profile_private_kref);
201 
202 void *spu_get_profile_private_kref(struct spu_context *ctx)
203 {
204 	return ctx->prof_priv_kref;
205 }
206 EXPORT_SYMBOL_GPL(spu_get_profile_private_kref);
207 
208 
209