diff options
Diffstat (limited to 'arch/powerpc/platforms/cell/spufs/context.c')
| -rw-r--r-- | arch/powerpc/platforms/cell/spufs/context.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/cell/spufs/context.c b/arch/powerpc/platforms/cell/spufs/context.c new file mode 100644 index 0000000000000..336f238102fd3 --- /dev/null +++ b/arch/powerpc/platforms/cell/spufs/context.c @@ -0,0 +1,167 @@ +/* + * 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 address_space *local_store) +{ + struct spu_context *ctx; + ctx = kmalloc(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); + kref_init(&ctx->kref); + init_rwsem(&ctx->state_sema); + init_MUTEX(&ctx->run_sema); + init_waitqueue_head(&ctx->ibox_wq); + init_waitqueue_head(&ctx->wbox_wq); + init_waitqueue_head(&ctx->stop_wq); + ctx->ibox_fasync = NULL; + ctx->wbox_fasync = NULL; + ctx->state = SPU_STATE_SAVED; + ctx->local_store = local_store; + ctx->spu = NULL; + ctx->ops = &spu_backing_ops; + ctx->owner = get_task_mm(current); + 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); + down_write(&ctx->state_sema); + spu_deactivate(ctx); + ctx->ibox_fasync = NULL; + ctx->wbox_fasync = NULL; + up_write(&ctx->state_sema); + spu_fini_csa(&ctx->csa); + 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_acquire(struct spu_context *ctx) +{ + down_read(&ctx->state_sema); +} + +void spu_release(struct spu_context *ctx) +{ + up_read(&ctx->state_sema); +} + +void spu_unmap_mappings(struct spu_context *ctx) +{ + unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1); +} + +int spu_acquire_runnable(struct spu_context *ctx) +{ + int ret = 0; + + down_read(&ctx->state_sema); + if (ctx->state == SPU_STATE_RUNNABLE) { + ctx->spu->prio = current->prio; + return 0; + } + up_read(&ctx->state_sema); + + down_write(&ctx->state_sema); + /* ctx is about to be freed, can't acquire any more */ + if (!ctx->owner) { + ret = -EINVAL; + goto out; + } + + if (ctx->state == SPU_STATE_SAVED) { + ret = spu_activate(ctx, 0); + if (ret) + goto out; + ctx->state = SPU_STATE_RUNNABLE; + } + + downgrade_write(&ctx->state_sema); + /* On success, we return holding the lock */ + + return ret; +out: + /* Release here, to simplify calling code. */ + up_write(&ctx->state_sema); + + return ret; +} + +void spu_acquire_saved(struct spu_context *ctx) +{ + down_read(&ctx->state_sema); + + if (ctx->state == SPU_STATE_SAVED) + return; + + up_read(&ctx->state_sema); + down_write(&ctx->state_sema); + + if (ctx->state == SPU_STATE_RUNNABLE) { + spu_deactivate(ctx); + ctx->state = SPU_STATE_SAVED; + } + + downgrade_write(&ctx->state_sema); +} |