1 files changed, 68 insertions, 69 deletions

diff --git a/arch/powerpc/platforms/cell/spufs/context.c b/arch/powerpc/platforms/cell/spufs/context.c
index 0870009f56db..04ad2e364e97 100644
--- a/arch/powerpc/platforms/cell/spufs/context.c
+++ b/arch/powerpc/platforms/cell/spufs/context.c
@@ -42,7 +42,7 @@ struct spu_context *alloc_spu_context(struct spu_gang *gang)
         }
         spin_lock_init(&ctx->mmio_lock);
         kref_init(&ctx->kref);
-        init_rwsem(&ctx->state_sema);
+        mutex_init(&ctx->state_mutex);
         init_MUTEX(&ctx->run_sema);
         init_waitqueue_head(&ctx->ibox_wq);
         init_waitqueue_head(&ctx->wbox_wq);
@@ -53,6 +53,10 @@ struct spu_context *alloc_spu_context(struct spu_gang *gang)
         ctx->owner = get_task_mm(current);
         if (gang)
                 spu_gang_add_ctx(gang, ctx);
+        ctx->rt_priority = current->rt_priority;
+        ctx->policy = current->policy;
+        ctx->prio = current->prio;
+        INIT_DELAYED_WORK(&ctx->sched_work, spu_sched_tick);
         goto out;
 out_free:
         kfree(ctx);
@@ -65,9 +69,9 @@ void destroy_spu_context(struct kref *kref)
 {
         struct spu_context *ctx;
         ctx = container_of(kref, struct spu_context, kref);
-        down_write(&ctx->state_sema);
+        mutex_lock(&ctx->state_mutex);
         spu_deactivate(ctx);
-        up_write(&ctx->state_sema);
+        mutex_unlock(&ctx->state_mutex);
         spu_fini_csa(&ctx->csa);
         if (ctx->gang)
                 spu_gang_remove_ctx(ctx->gang, ctx);
@@ -96,107 +100,102 @@ void spu_forget(struct spu_context *ctx)
         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)
 {
         if (ctx->local_store)
                 unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
         if (ctx->mfc)
-                unmap_mapping_range(ctx->mfc, 0, 0x4000, 1);
+                unmap_mapping_range(ctx->mfc, 0, 0x1000, 1);
         if (ctx->cntl)
-                unmap_mapping_range(ctx->cntl, 0, 0x4000, 1);
+                unmap_mapping_range(ctx->cntl, 0, 0x1000, 1);
         if (ctx->signal1)
-                unmap_mapping_range(ctx->signal1, 0, 0x4000, 1);
+                unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1);
         if (ctx->signal2)
-                unmap_mapping_range(ctx->signal2, 0, 0x4000, 1);
+                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);
 }
 
+/**
+ * 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 = 0;
+        int ret = -EINVAL;
 
-        down_write(&ctx->state_sema);
-        /* ctx is about to be freed, can't acquire any more */
-        if (!ctx->owner) {
-                ret = -EINVAL;
-                goto out;
-        }
+        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;
-                ctx->state = SPU_STATE_RUNNABLE;
+                        goto out_unlock;
         } else {
-                /* We need to exclude userspace access to the context. */
+                /*
+                 * 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);
         }
 
-out:
-        if (ret)
-                up_write(&ctx->state_sema);
+        return 0;
+
+ out_unlock:
+        spu_release(ctx);
         return ret;
 }
 
-int spu_acquire_runnable(struct spu_context *ctx)
+/**
+ * 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 = 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;
-        }
+        int ret = -EINVAL;
 
+        spu_acquire(ctx);
         if (ctx->state == SPU_STATE_SAVED) {
-                ret = spu_activate(ctx, 0);
+                /*
+                 * 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;
-                ctx->state = SPU_STATE_RUNNABLE;
+                        goto out_unlock;
         }
 
-        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 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)
 {
-        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_acquire(ctx);
+        if (ctx->state != SPU_STATE_SAVED)
                 spu_deactivate(ctx);
-                ctx->state = SPU_STATE_SAVED;
-        }
-
-        downgrade_write(&ctx->state_sema);
 }