This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / arch / powerpc / platforms / cell / spufs / context.c

diff --git a/arch/powerpc/platforms/cell/spufs/context.c b/arch/powerpc/platforms/cell/spufs/context.c
new file mode 100644 (file)
index 0000000..8bb33ab
--- /dev/null
+++ b/arch/powerpc/platforms/cell/spufs/context.c
@@ -0,0 +1,181 @@
+/*
+ * 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(void)
+{
+       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);
+       init_waitqueue_head(&ctx->mfc_wq);
+       ctx->ibox_fasync = NULL;
+       ctx->wbox_fasync = NULL;
+       ctx->mfc_fasync = NULL;
+       ctx->mfc = NULL;
+       ctx->tagwait = 0;
+       ctx->state = SPU_STATE_SAVED;
+       ctx->local_store = NULL;
+       ctx->cntl = NULL;
+       ctx->signal1 = NULL;
+       ctx->signal2 = NULL;
+       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);
+       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)
+{
+       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);
+       if (ctx->cntl)
+               unmap_mapping_range(ctx->cntl, 0, 0x4000, 1);
+       if (ctx->signal1)
+               unmap_mapping_range(ctx->signal1, 0, 0x4000, 1);
+       if (ctx->signal2)
+               unmap_mapping_range(ctx->signal2, 0, 0x4000, 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);
+}