mmap routines
Signed-off-by: Kamal Heib <kam...@mellanox.com>
Signed-off-by: Amir Vadai <am...@mellanox.com>
Reviewed-by: Haggai Eran <hagg...@mellanox.com>
---
drivers/staging/rdma/rxe/rxe_mmap.c | 173 ++++++++++++++++++++++++++++++++++++
1 file changed, 173 insertions(+)
create mode 100644 drivers/staging/rdma/rxe/rxe_mmap.c
diff --git a/drivers/staging/rdma/rxe/rxe_mmap.c
b/drivers/staging/rdma/rxe/rxe_mmap.c
new file mode 100644
index 0000000..fbe3e1d
--- /dev/null
+++ b/drivers/staging/rdma/rxe/rxe_mmap.c
@@ -0,0 +1,173 @@
+/*
+ * Copyright (c) 2015 Mellanox Technologies Ltd. All rights reserved.
+ * Copyright (c) 2015 System Fabric Works, 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 "rxe.h"
+#include "rxe_loc.h"
+#include "rxe_queue.h"
+
+void rxe_mmap_release(struct kref *ref)
+{
+ struct rxe_mmap_info *ip = container_of(ref,
+ struct rxe_mmap_info, ref);
+ struct rxe_dev *rxe = to_rdev(ip->context->device);
+
+ spin_lock_bh(&rxe->pending_lock);
+
+ if (!list_empty(&ip->pending_mmaps))
+ list_del(&ip->pending_mmaps);
+
+ spin_unlock_bh(&rxe->pending_lock);
+
+ vfree(ip->obj); /* buf */
+ kfree(ip);
+}
+
+/*
+ * open and close keep track of how many times the memory region is mapped,
+ * to avoid releasing it.
+ */
+static void rxe_vma_open(struct vm_area_struct *vma)
+{
+ struct rxe_mmap_info *ip = vma->vm_private_data;
+
+ kref_get(&ip->ref);
+}
+
+static void rxe_vma_close(struct vm_area_struct *vma)
+{
+ struct rxe_mmap_info *ip = vma->vm_private_data;
+
+ kref_put(&ip->ref, rxe_mmap_release);
+}
+
+static struct vm_operations_struct rxe_vm_ops = {
+ .open = rxe_vma_open,
+ .close = rxe_vma_close,
+};
+
+/**
+ * rxe_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 rxe_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
+{
+ struct rxe_dev *rxe = to_rdev(context->device);
+ unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+ unsigned long size = vma->vm_end - vma->vm_start;
+ struct rxe_mmap_info *ip, *pp;
+ int ret;
+
+ /*
+ * 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_bh(&rxe->pending_lock);
+ list_for_each_entry_safe(ip, pp, &rxe->pending_mmaps, pending_mmaps) {
+ if (context != ip->context || (__u64)offset != ip->info.offset)
+ continue;
+
+ /* Don't allow a mmap larger than the object. */
+ if (size > ip->info.size) {
+ pr_err("mmap region is larger than the object!\n");
+ spin_unlock_bh(&rxe->pending_lock);
+ ret = -EINVAL;
+ goto done;
+ }
+
+ goto found_it;
+ }
+ pr_warn("unable to find pending mmap info\n");
+ spin_unlock_bh(&rxe->pending_lock);
+ ret = -EINVAL;
+ goto done;
+
+found_it:
+ list_del_init(&ip->pending_mmaps);
+ spin_unlock_bh(&rxe->pending_lock);
+
+ ret = remap_vmalloc_range(vma, ip->obj, 0);
+ if (ret) {
+ pr_err("rxe: err %d from remap_vmalloc_range\n", ret);
+ goto done;
+ }
+
+ vma->vm_ops = &rxe_vm_ops;
+ vma->vm_private_data = ip;
+ rxe_vma_open(vma);
+done:
+ return ret;
+}
+
+/*
+ * Allocate information for rxe_mmap
+ */
+struct rxe_mmap_info *rxe_create_mmap_info(struct rxe_dev *rxe,
+ u32 size,
+ struct ib_ucontext *context,
+ void *obj)
+{
+ struct rxe_mmap_info *ip;
+
+ ip = kmalloc(sizeof(*ip), GFP_KERNEL);
+ if (!ip)
+ return NULL;
+
+ size = PAGE_ALIGN(size);
+
+ spin_lock_bh(&rxe->mmap_offset_lock);
+
+ if (rxe->mmap_offset == 0)
+ rxe->mmap_offset = PAGE_SIZE;
+
+ ip->info.offset = rxe->mmap_offset;
+ rxe->mmap_offset += size;
+
+ spin_unlock_bh(&rxe->mmap_offset_lock);
+
+ INIT_LIST_HEAD(&ip->pending_mmaps);
+ ip->info.size = size;
+ ip->context = context;
+ ip->obj = obj;
+ kref_init(&ip->ref);
+
+ return ip;
+}
--
1.8.3.1
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