1/* 2 * Copyright (c) 2006 QLogic, Inc. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 */ 32 33#include <linux/module.h> 34#include <linux/vmalloc.h> 35#include <linux/mm.h> 36#include <linux/errno.h> 37#include <asm/pgtable.h> 38 39#include "ipath_verbs.h" 40 41/** 42 * ipath_release_mmap_info - free mmap info structure 43 * @ref: a pointer to the kref within struct ipath_mmap_info 44 */ 45void ipath_release_mmap_info(struct kref *ref) 46{ 47 struct ipath_mmap_info *ip = 48 container_of(ref, struct ipath_mmap_info, ref); 49 struct ipath_ibdev *dev = to_idev(ip->context->device); 50 51 spin_lock_irq(&dev->pending_lock); 52 list_del(&ip->pending_mmaps); 53 spin_unlock_irq(&dev->pending_lock); 54 55 vfree(ip->obj); 56 kfree(ip); 57} 58 59/* 60 * open and close keep track of how many times the CQ is mapped, 61 * to avoid releasing it. 62 */ 63static void ipath_vma_open(struct vm_area_struct *vma) 64{ 65 struct ipath_mmap_info *ip = vma->vm_private_data; 66 67 kref_get(&ip->ref); 68} 69 70static void ipath_vma_close(struct vm_area_struct *vma) 71{ 72 struct ipath_mmap_info *ip = vma->vm_private_data; 73 74 kref_put(&ip->ref, ipath_release_mmap_info); 75} 76 77static struct vm_operations_struct ipath_vm_ops = { 78 .open = ipath_vma_open, 79 .close = ipath_vma_close, 80}; 81 82/** 83 * ipath_mmap - create a new mmap region 84 * @context: the IB user context of the process making the mmap() call 85 * @vma: the VMA to be initialized 86 * Return zero if the mmap is OK. Otherwise, return an errno. 87 */ 88int ipath_mmap(struct ib_ucontext *context, struct vm_area_struct *vma) 89{ 90 struct ipath_ibdev *dev = to_idev(context->device); 91 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; 92 unsigned long size = vma->vm_end - vma->vm_start; 93 struct ipath_mmap_info *ip, *pp; 94 int ret = -EINVAL; 95 96 /* 97 * Search the device's list of objects waiting for a mmap call. 98 * Normally, this list is very short since a call to create a 99 * CQ, QP, or SRQ is soon followed by a call to mmap(). 100 */ 101 spin_lock_irq(&dev->pending_lock); 102 list_for_each_entry_safe(ip, pp, &dev->pending_mmaps, 103 pending_mmaps) { 104 /* Only the creator is allowed to mmap the object */ 105 if (context != ip->context || (__u64) offset != ip->offset) 106 continue; 107 /* Don't allow a mmap larger than the object. */ 108 if (size > ip->size) 109 break; 110 111 list_del_init(&ip->pending_mmaps); 112 spin_unlock_irq(&dev->pending_lock); 113 114 ret = remap_vmalloc_range(vma, ip->obj, 0); 115 if (ret) 116 goto done; 117 vma->vm_ops = &ipath_vm_ops; 118 vma->vm_private_data = ip; 119 ipath_vma_open(vma); 120 goto done; 121 } 122 spin_unlock_irq(&dev->pending_lock); 123done: 124 return ret; 125} 126 127/* 128 * Allocate information for ipath_mmap 129 */ 130struct ipath_mmap_info *ipath_create_mmap_info(struct ipath_ibdev *dev, 131 u32 size, 132 struct ib_ucontext *context, 133 void *obj) { 134 struct ipath_mmap_info *ip; 135 136 ip = kmalloc(sizeof *ip, GFP_KERNEL); 137 if (!ip) 138 goto bail; 139 140 size = PAGE_ALIGN(size); 141 142 spin_lock_irq(&dev->mmap_offset_lock); 143 if (dev->mmap_offset == 0) 144 dev->mmap_offset = PAGE_SIZE; 145 ip->offset = dev->mmap_offset; 146 dev->mmap_offset += size; 147 spin_unlock_irq(&dev->mmap_offset_lock); 148 149 INIT_LIST_HEAD(&ip->pending_mmaps); 150 ip->size = size; 151 ip->context = context; 152 ip->obj = obj; 153 kref_init(&ip->ref); 154 155bail: 156 return ip; 157} 158 159void ipath_update_mmap_info(struct ipath_ibdev *dev, 160 struct ipath_mmap_info *ip, 161 u32 size, void *obj) { 162 size = PAGE_ALIGN(size); 163 164 spin_lock_irq(&dev->mmap_offset_lock); 165 if (dev->mmap_offset == 0) 166 dev->mmap_offset = PAGE_SIZE; 167 ip->offset = dev->mmap_offset; 168 dev->mmap_offset += size; 169 spin_unlock_irq(&dev->mmap_offset_lock); 170 171 ip->size = size; 172 ip->obj = obj; 173} 174