/*
* Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. 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/slab.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <asm/pgtable.h>
#include "qib_verbs.h"
/**
* qib_release_mmap_info - free mmap info structure
* @ref: a pointer to the kref within struct qib_mmap_info
*/
void qib_release_mmap_info(struct kref *ref)
{
struct qib_mmap_info *ip =
container_of(ref, struct qib_mmap_info, ref);
struct qib_ibdev *dev = to_idev(ip->context->device);
spin_lock_irq(&dev->pending_lock);
list_del(&ip->pending_mmaps);
spin_unlock_irq(&dev->pending_lock);
vfree(ip->obj);
kfree(ip);
}
/*
* open and close keep track of how many times the CQ is mapped,
* to avoid releasing it.
*/
static void qib_vma_open(struct vm_area_struct *vma)
{
struct qib_mmap_info *ip = vma->vm_private_data;
kref_get(&ip->ref);
}
static void qib_vma_close(struct vm_area_struct *vma)
{
struct qib_mmap_info *ip = vma->vm_private_data;
kref_put(&ip->ref, qib_release_mmap_info);
}
static struct vm_operations_struct qib_vm_ops = {
.open = qib_vma_open,
.close = qib_vma_close,
};
/**
* qib_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 qib_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
{
struct qib_ibdev *dev = to_idev(context->device);
unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
unsigned long size = vma->vm_end - vma->vm_start;
struct qib_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);
list_for_each_entry_safe(ip, pp, &dev->pending_mmaps,
pending_mmaps) {
/* Only the creator is allowed to mmap the object */
if (context != ip->context || (__u64) offset != ip->offset)
continue;
/* Don't allow a mmap larger than the object. */
if (size > ip->size)
break;
list_del_init(&ip->pending_mmaps);
spin_unlock_irq(&dev->pending_lock);
ret = remap_vmalloc_range(vma, ip->obj, 0);
if (ret)
goto done;
vma->vm_ops = &qib_vm_ops;
vma->vm_private_data = ip;
qib_vma_open(vma);
goto done;
}
spin_unlock_irq(&dev->pending_lock);
done:
return ret;
}
/*
* Allocate information for qib_mmap
*/
struct qib_mmap_info *qib_create_mmap_info(struct qib_ibdev *dev,
u32 size,
struct ib_ucontext *context,
void *obj) {
struct qib_mmap_info *ip;
ip = kmalloc(sizeof *ip, GFP_KERNEL);
if (!ip)
goto bail;
size = PAGE_ALIGN(size);
spin_lock_irq(&dev->mmap_offset_lock);
if (dev->mmap_offset == 0)
dev->mmap_offset = PAGE_SIZE;
ip->offset = dev->mmap_offset;
dev->mmap_offset += size;
spin_unlock_irq(&dev->mmap_offset_lock);
INIT_LIST_HEAD(&ip->pending_mmaps);
ip->size = size;
ip->context = context;
ip->obj = obj;
kref_init(&ip->ref);
bail:
return ip;
}
void qib_update_mmap_info(struct qib_ibdev *dev, struct qib_mmap_info *ip,
u32 size, void *obj)
{
size = PAGE_ALIGN(size);
spin_lock_irq(&dev->mmap_offset_lock);
if (dev->mmap_offset == 0)
dev->mmap_offset = PAGE_SIZE;
ip->offset = dev->mmap_offset;
dev->mmap_offset += size;
spin_unlock_irq(&dev->mmap_offset_lock);
ip->size = size;
ip->obj = obj;
}
