2 * SPU file system -- SPU context management
4 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
6 * Author: Arnd Bergmann <arndb@de.ibm.com>
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)
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.
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.
25 #include <linux/slab.h>
27 #include <asm/spu_csa.h>
30 struct spu_context *alloc_spu_context(void)
32 struct spu_context *ctx;
33 ctx = kmalloc(sizeof *ctx, GFP_KERNEL);
36 /* Binding to physical processor deferred
37 * until spu_activate().
39 spu_init_csa(&ctx->csa);
40 if (!ctx->csa.lscsa) {
43 spin_lock_init(&ctx->mmio_lock);
44 kref_init(&ctx->kref);
45 init_rwsem(&ctx->state_sema);
46 init_MUTEX(&ctx->run_sema);
47 init_waitqueue_head(&ctx->ibox_wq);
48 init_waitqueue_head(&ctx->wbox_wq);
49 init_waitqueue_head(&ctx->stop_wq);
50 init_waitqueue_head(&ctx->mfc_wq);
51 ctx->ibox_fasync = NULL;
52 ctx->wbox_fasync = NULL;
53 ctx->mfc_fasync = NULL;
55 ctx->state = SPU_STATE_SAVED;
56 ctx->local_store = NULL;
61 ctx->ops = &spu_backing_ops;
62 ctx->owner = get_task_mm(current);
71 void destroy_spu_context(struct kref *kref)
73 struct spu_context *ctx;
74 ctx = container_of(kref, struct spu_context, kref);
75 down_write(&ctx->state_sema);
77 up_write(&ctx->state_sema);
78 spu_fini_csa(&ctx->csa);
82 struct spu_context * get_spu_context(struct spu_context *ctx)
88 int put_spu_context(struct spu_context *ctx)
90 return kref_put(&ctx->kref, &destroy_spu_context);
93 /* give up the mm reference when the context is about to be destroyed */
94 void spu_forget(struct spu_context *ctx)
97 spu_acquire_saved(ctx);
104 void spu_acquire(struct spu_context *ctx)
106 down_read(&ctx->state_sema);
109 void spu_release(struct spu_context *ctx)
111 up_read(&ctx->state_sema);
114 void spu_unmap_mappings(struct spu_context *ctx)
116 if (ctx->local_store)
117 unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
119 unmap_mapping_range(ctx->mfc, 0, 0x4000, 1);
121 unmap_mapping_range(ctx->cntl, 0, 0x4000, 1);
123 unmap_mapping_range(ctx->signal1, 0, 0x4000, 1);
125 unmap_mapping_range(ctx->signal2, 0, 0x4000, 1);
128 int spu_acquire_runnable(struct spu_context *ctx)
132 down_read(&ctx->state_sema);
133 if (ctx->state == SPU_STATE_RUNNABLE) {
134 ctx->spu->prio = current->prio;
137 up_read(&ctx->state_sema);
139 down_write(&ctx->state_sema);
140 /* ctx is about to be freed, can't acquire any more */
146 if (ctx->state == SPU_STATE_SAVED) {
147 ret = spu_activate(ctx, 0);
150 ctx->state = SPU_STATE_RUNNABLE;
153 downgrade_write(&ctx->state_sema);
154 /* On success, we return holding the lock */
158 /* Release here, to simplify calling code. */
159 up_write(&ctx->state_sema);
164 void spu_acquire_saved(struct spu_context *ctx)
166 down_read(&ctx->state_sema);
168 if (ctx->state == SPU_STATE_SAVED)
171 up_read(&ctx->state_sema);
172 down_write(&ctx->state_sema);
174 if (ctx->state == SPU_STATE_RUNNABLE) {
176 ctx->state = SPU_STATE_SAVED;
179 downgrade_write(&ctx->state_sema);