aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/platforms/cell/spufs/context.c
blob: ce17a2847184018992c0fb79fd79476ac842c541 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
/*
 * SPU file system -- SPU context management
 *
 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
 *
 * Author: Arnd Bergmann <arndb@de.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <asm/spu.h>
#include <asm/spu_csa.h>
#include "spufs.h"

struct spu_context *alloc_spu_context(struct spu_gang *gang)
{
	struct spu_context *ctx;
	ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
	if (!ctx)
		goto out;
	/* Binding to physical processor deferred
	 * until spu_activate().
	 */
	spu_init_csa(&ctx->csa);
	if (!ctx->csa.lscsa) {
		goto out_free;
	}
	spin_lock_init(&ctx->mmio_lock);
	spin_lock_init(&ctx->mapping_lock);
	kref_init(&ctx->kref);
	mutex_init(&ctx->state_mutex);
	init_MUTEX(&ctx->run_sema);
	init_waitqueue_head(&ctx->ibox_wq);
	init_waitqueue_head(&ctx->wbox_wq);
	init_waitqueue_head(&ctx->stop_wq);
	init_waitqueue_head(&ctx->mfc_wq);
	ctx->state = SPU_STATE_SAVED;
	ctx->ops = &spu_backing_ops;
	ctx->owner = get_task_mm(current);
	INIT_LIST_HEAD(&ctx->rq);
	if (gang)
		spu_gang_add_ctx(gang, ctx);
	ctx->rt_priority = current->rt_priority;
	ctx->policy = current->policy;
	ctx->prio = current->prio;
	INIT_DELAYED_WORK(&ctx->sched_work, spu_sched_tick);
	goto out;
out_free:
	kfree(ctx);
	ctx = NULL;
out:
	return ctx;
}

void destroy_spu_context(struct kref *kref)
{
	struct spu_context *ctx;
	ctx = container_of(kref, struct spu_context, kref);
	mutex_lock(&ctx->state_mutex);
	spu_deactivate(ctx);
	mutex_unlock(&ctx->state_mutex);
	spu_fini_csa(&ctx->csa);
	if (ctx->gang)
		spu_gang_remove_ctx(ctx->gang, ctx);
	BUG_ON(!list_empty(&ctx->rq));
	kfree(ctx);
}

struct spu_context * get_spu_context(struct spu_context *ctx)
{
	kref_get(&ctx->kref);
	return ctx;
}

int put_spu_context(struct spu_context *ctx)
{
	return kref_put(&ctx->kref, &destroy_spu_context);
}

/* give up the mm reference when the context is about to be destroyed */
void spu_forget(struct spu_context *ctx)
{
	struct mm_struct *mm;
	spu_acquire_saved(ctx);
	mm = ctx->owner;
	ctx->owner = NULL;
	mmput(mm);
	spu_release(ctx);
}

void spu_unmap_mappings(struct spu_context *ctx)
{
	if (ctx->local_store)
		unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
	if (ctx->mfc)
		unmap_mapping_range(ctx->mfc, 0, 0x1000, 1);
	if (ctx->cntl)
		unmap_mapping_range(ctx->cntl, 0, 0x1000, 1);
	if (ctx->signal1)
		unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1);
	if (ctx->signal2)
		unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1);
	if (ctx->mss)
		unmap_mapping_range(ctx->mss, 0, 0x1000, 1);
	if (ctx->psmap)
		unmap_mapping_range(ctx->psmap, 0, 0x20000, 1);
}

/**
 * spu_acquire_runnable - lock spu contex and make sure it is in runnable state
 * @ctx:	spu contex to lock
 *
 * Note:
 *	Returns 0 and with the context locked on success
 *	Returns negative error and with the context _unlocked_ on failure.
 */
int spu_acquire_runnable(struct spu_context *ctx, unsigned long flags)
{
	int ret = -EINVAL;

	spu_acquire(ctx);
	if (ctx->state == SPU_STATE_SAVED) {
		/*
		 * Context is about to be freed, so we can't acquire it anymore.
		 */
		if (!ctx->owner)
			goto out_unlock;
		ret = spu_activate(ctx, flags);
		if (ret)
			goto out_unlock;
	}

	return 0;

 out_unlock:
	spu_release(ctx);
	return ret;
}

/**
 * spu_acquire_saved - lock spu contex and make sure it is in saved state
 * @ctx:	spu contex to lock
 */
void spu_acquire_saved(struct spu_context *ctx)
{
	spu_acquire(ctx);
	if (ctx->state != SPU_STATE_SAVED)
		spu_deactivate(ctx);
}