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

[linux-2.6.git] / drivers / infiniband / hw / ipath / ipath_mmap.c

diff --git a/drivers/infiniband/hw/ipath/ipath_mmap.c b/drivers/infiniband/hw/ipath/ipath_mmap.c
new file mode 100644 (file)
index 0000000..a82157d
--- /dev/null
+++ b/drivers/infiniband/hw/ipath/ipath_mmap.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2006 QLogic, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <asm/pgtable.h>
+
+#include "ipath_verbs.h"
+
+/**
+ * ipath_release_mmap_info - free mmap info structure
+ * @ref: a pointer to the kref within struct ipath_mmap_info
+ */
+void ipath_release_mmap_info(struct kref *ref)
+{
+       struct ipath_mmap_info *ip =
+               container_of(ref, struct ipath_mmap_info, ref);
+
+       vfree(ip->obj);
+       kfree(ip);
+}
+
+/*
+ * open and close keep track of how many times the CQ is mapped,
+ * to avoid releasing it.
+ */
+static void ipath_vma_open(struct vm_area_struct *vma)
+{
+       struct ipath_mmap_info *ip = vma->vm_private_data;
+
+       kref_get(&ip->ref);
+       ip->mmap_cnt++;
+}
+
+static void ipath_vma_close(struct vm_area_struct *vma)
+{
+       struct ipath_mmap_info *ip = vma->vm_private_data;
+
+       ip->mmap_cnt--;
+       kref_put(&ip->ref, ipath_release_mmap_info);
+}
+
+static struct vm_operations_struct ipath_vm_ops = {
+       .open =     ipath_vma_open,
+       .close =    ipath_vma_close,
+};
+
+/**
+ * ipath_mmap - create a new mmap region
+ * @context: the IB user context of the process making the mmap() call
+ * @vma: the VMA to be initialized
+ * Return zero if the mmap is OK. Otherwise, return an errno.
+ */
+int ipath_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
+{
+       struct ipath_ibdev *dev = to_idev(context->device);
+       unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+       unsigned long size = vma->vm_end - vma->vm_start;
+       struct ipath_mmap_info *ip, **pp;
+       int ret = -EINVAL;
+
+       /*
+        * Search the device's list of objects waiting for a mmap call.
+        * Normally, this list is very short since a call to create a
+        * CQ, QP, or SRQ is soon followed by a call to mmap().
+        */
+       spin_lock_irq(&dev->pending_lock);
+       for (pp = &dev->pending_mmaps; (ip = *pp); pp = &ip->next) {
+               /* Only the creator is allowed to mmap the object */
+               if (context != ip->context || (void *) offset != ip->obj)
+                       continue;
+               /* Don't allow a mmap larger than the object. */
+               if (size > ip->size)
+                       break;
+
+               *pp = ip->next;
+               spin_unlock_irq(&dev->pending_lock);
+
+               ret = remap_vmalloc_range(vma, ip->obj, 0);
+               if (ret)
+                       goto done;
+               vma->vm_ops = &ipath_vm_ops;
+               vma->vm_private_data = ip;
+               ipath_vma_open(vma);
+               goto done;
+       }
+       spin_unlock_irq(&dev->pending_lock);
+done:
+       return ret;
+}