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_waitqueue_head(&ctx
->ibox_wq
);
47 init_waitqueue_head(&ctx
->wbox_wq
);
48 init_waitqueue_head(&ctx
->stop_wq
);
49 ctx
->ibox_fasync
= NULL
;
50 ctx
->wbox_fasync
= NULL
;
51 ctx
->state
= SPU_STATE_SAVED
;
52 ctx
->local_store
= local_store
;
54 ctx
->ops
= &spu_backing_ops
;
55 ctx
->owner
= get_task_mm(current
);
64 void destroy_spu_context(struct kref
*kref
)
66 struct spu_context
*ctx
;
67 ctx
= container_of(kref
, struct spu_context
, kref
);
68 down_write(&ctx
->state_sema
);
70 ctx
->ibox_fasync
= NULL
;
71 ctx
->wbox_fasync
= NULL
;
72 up_write(&ctx
->state_sema
);
73 spu_fini_csa(&ctx
->csa
);
77 struct spu_context
* get_spu_context(struct spu_context
*ctx
)
83 int put_spu_context(struct spu_context
*ctx
)
85 return kref_put(&ctx
->kref
, &destroy_spu_context
);
88 /* give up the mm reference when the context is about to be destroyed */
89 void spu_forget(struct spu_context
*ctx
)
92 spu_acquire_saved(ctx
);
99 void spu_acquire(struct spu_context
*ctx
)
101 down_read(&ctx
->state_sema
);
104 void spu_release(struct spu_context
*ctx
)
106 up_read(&ctx
->state_sema
);
109 void spu_unmap_mappings(struct spu_context
*ctx
)
111 unmap_mapping_range(ctx
->local_store
, 0, LS_SIZE
, 1);
114 int spu_acquire_runnable(struct spu_context
*ctx
)
118 down_read(&ctx
->state_sema
);
119 if (ctx
->state
== SPU_STATE_RUNNABLE
) {
120 ctx
->spu
->prio
= current
->prio
;
123 up_read(&ctx
->state_sema
);
125 down_write(&ctx
->state_sema
);
126 /* ctx is about to be freed, can't acquire any more */
132 if (ctx
->state
== SPU_STATE_SAVED
) {
133 ret
= spu_activate(ctx
, 0);
134 ctx
->state
= SPU_STATE_RUNNABLE
;
139 downgrade_write(&ctx
->state_sema
);
140 /* On success, we return holding the lock */
144 /* Release here, to simplify calling code. */
145 up_write(&ctx
->state_sema
);
150 void spu_acquire_saved(struct spu_context
*ctx
)
152 down_read(&ctx
->state_sema
);
154 if (ctx
->state
== SPU_STATE_SAVED
)
157 up_read(&ctx
->state_sema
);
158 down_write(&ctx
->state_sema
);
160 if (ctx
->state
== SPU_STATE_RUNNABLE
) {
162 ctx
->state
= SPU_STATE_SAVED
;
165 downgrade_write(&ctx
->state_sema
);