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(struct address_space *local_store)
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 = local_store;
58 ctx->ops = &spu_backing_ops;
59 ctx->owner = get_task_mm(current);
68 void destroy_spu_context(struct kref *kref)
70 struct spu_context *ctx;
71 ctx = container_of(kref, struct spu_context, kref);
72 down_write(&ctx->state_sema);
74 up_write(&ctx->state_sema);
75 spu_fini_csa(&ctx->csa);
79 struct spu_context * get_spu_context(struct spu_context *ctx)
85 int put_spu_context(struct spu_context *ctx)
87 return kref_put(&ctx->kref, &destroy_spu_context);
90 /* give up the mm reference when the context is about to be destroyed */
91 void spu_forget(struct spu_context *ctx)
94 spu_acquire_saved(ctx);
101 void spu_acquire(struct spu_context *ctx)
103 down_read(&ctx->state_sema);
106 void spu_release(struct spu_context *ctx)
108 up_read(&ctx->state_sema);
111 void spu_unmap_mappings(struct spu_context *ctx)
113 unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
116 int spu_acquire_runnable(struct spu_context *ctx)
120 down_read(&ctx->state_sema);
121 if (ctx->state == SPU_STATE_RUNNABLE) {
122 ctx->spu->prio = current->prio;
125 up_read(&ctx->state_sema);
127 down_write(&ctx->state_sema);
128 /* ctx is about to be freed, can't acquire any more */
134 if (ctx->state == SPU_STATE_SAVED) {
135 ret = spu_activate(ctx, 0);
138 ctx->state = SPU_STATE_RUNNABLE;
141 downgrade_write(&ctx->state_sema);
142 /* On success, we return holding the lock */
146 /* Release here, to simplify calling code. */
147 up_write(&ctx->state_sema);
152 void spu_acquire_saved(struct spu_context *ctx)
154 down_read(&ctx->state_sema);
156 if (ctx->state == SPU_STATE_SAVED)
159 up_read(&ctx->state_sema);
160 down_write(&ctx->state_sema);
162 if (ctx->state == SPU_STATE_RUNNABLE) {
164 ctx->state = SPU_STATE_SAVED;
167 downgrade_write(&ctx->state_sema);