/**
* spu_acquire_exclusive - lock spu contex and protect against userspace access
* @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_exclusive(struct spu_context *ctx)
{
int ret = -EINVAL;
spu_acquire(ctx);
/*
* Context is about to be freed, so we can't acquire it anymore.
*/
if (!ctx->owner)
goto out_unlock;
if (ctx->state == SPU_STATE_SAVED) {
ret = spu_activate(ctx, 0);
if (ret)
goto out_unlock;
} else {
/*
* We need to exclude userspace access to the context.
*
* To protect against memory access we invalidate all ptes
* and make sure the pagefault handlers block on the mutex.
*/
spu_unmap_mappings(ctx);
}
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
*/
int spu_acquire_saved(struct spu_context *ctx)
{
int ret;
spu_context_nospu_trace(spu_acquire_saved__enter, ctx);
ret = spu_acquire(ctx);
if (ret)
return ret;
if (ctx->state != SPU_STATE_SAVED) {
set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
spu_deactivate(ctx);
}
return 0;
}
/**
* 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);
}
