| /* |
| * 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/atomic.h> |
| #include <asm/spu.h> |
| #include <asm/spu_csa.h> |
| #include "spufs.h" |
| |
| |
| atomic_t nr_spu_contexts = ATOMIC_INIT(0); |
| |
| struct spu_context *alloc_spu_context(struct spu_gang *gang) |
| { |
| struct spu_context *ctx; |
| ctx = kzalloc(sizeof *ctx, GFP_KERNEL); |
| if (!ctx) |
| goto out; |
| /* Binding to physical processor deferred |
| * until spu_activate(). |
| */ |
| if (spu_init_csa(&ctx->csa)) |
| goto out_free; |
| spin_lock_init(&ctx->mmio_lock); |
| mutex_init(&ctx->mapping_lock); |
| kref_init(&ctx->kref); |
| mutex_init(&ctx->state_mutex); |
| mutex_init(&ctx->run_mutex); |
| init_waitqueue_head(&ctx->ibox_wq); |
| init_waitqueue_head(&ctx->wbox_wq); |
| init_waitqueue_head(&ctx->stop_wq); |
| init_waitqueue_head(&ctx->mfc_wq); |
| ctx->state = SPU_STATE_SAVED; |
| ctx->ops = &spu_backing_ops; |
| ctx->owner = get_task_mm(current); |
| INIT_LIST_HEAD(&ctx->rq); |
| if (gang) |
| spu_gang_add_ctx(gang, ctx); |
| ctx->cpus_allowed = current->cpus_allowed; |
| spu_set_timeslice(ctx); |
| ctx->stats.util_state = SPU_UTIL_IDLE_LOADED; |
| |
| atomic_inc(&nr_spu_contexts); |
| 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); |
| mutex_lock(&ctx->state_mutex); |
| spu_deactivate(ctx); |
| mutex_unlock(&ctx->state_mutex); |
| spu_fini_csa(&ctx->csa); |
| if (ctx->gang) |
| spu_gang_remove_ctx(ctx->gang, ctx); |
| BUG_ON(!list_empty(&ctx->rq)); |
| atomic_dec(&nr_spu_contexts); |
| 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_unmap_mappings(struct spu_context *ctx) |
| { |
| mutex_lock(&ctx->mapping_lock); |
| if (ctx->local_store) |
| unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1); |
| if (ctx->mfc) |
| unmap_mapping_range(ctx->mfc, 0, 0x1000, 1); |
| if (ctx->cntl) |
| unmap_mapping_range(ctx->cntl, 0, 0x1000, 1); |
| if (ctx->signal1) |
| unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1); |
| if (ctx->signal2) |
| unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1); |
| if (ctx->mss) |
| unmap_mapping_range(ctx->mss, 0, 0x1000, 1); |
| if (ctx->psmap) |
| unmap_mapping_range(ctx->psmap, 0, 0x20000, 1); |
| mutex_unlock(&ctx->mapping_lock); |
| } |
| |
| /** |
| * 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) { |
| set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags); |
| spu_deactivate(ctx); |
| } |
| } |
| |
| /** |
| * spu_release_saved - unlock spu context and return it to the runqueue |
| * @ctx: context to unlock |
| */ |
| void spu_release_saved(struct spu_context *ctx) |
| { |
| BUG_ON(ctx->state != SPU_STATE_SAVED); |
| |
| if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags)) |
| spu_activate(ctx, 0); |
| |
| spu_release(ctx); |
| } |