LXR linux/drivers/infiniband/sw/rdmavt/mmap.c

   1/*
   2 * Copyright(c) 2016 Intel Corporation.
   3 *
   4 * This file is provided under a dual BSD/GPLv2 license.  When using or
   5 * redistributing this file, you may do so under either license.
   6 *
   7 * GPL LICENSE SUMMARY
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of version 2 of the GNU General Public License as
  11 * published by the Free Software Foundation.
  12 *
  13 * This program is distributed in the hope that it will be useful, but
  14 * WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 * General Public License for more details.
  17 *
  18 * BSD LICENSE
  19 *
  20 * Redistribution and use in source and binary forms, with or without
  21 * modification, are permitted provided that the following conditions
  22 * are met:
  23 *
  24 *  - Redistributions of source code must retain the above copyright
  25 *    notice, this list of conditions and the following disclaimer.
  26 *  - Redistributions in binary form must reproduce the above copyright
  27 *    notice, this list of conditions and the following disclaimer in
  28 *    the documentation and/or other materials provided with the
  29 *    distribution.
  30 *  - Neither the name of Intel Corporation nor the names of its
  31 *    contributors may be used to endorse or promote products derived
  32 *    from this software without specific prior written permission.
  33 *
  34 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  35 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  36 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  37 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  38 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  39 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  40 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  41 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  42 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  43 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  45 *
  46 */
  47
  48#include <linux/slab.h>
  49#include <linux/vmalloc.h>
  50#include <linux/mm.h>
  51#include <asm/pgtable.h>
  52#include <rdma/uverbs_ioctl.h>
  53#include "mmap.h"
  54
  55/**
  56 * rvt_mmap_init - init link list and lock for mem map
  57 * @rdi: rvt dev struct
  58 */
  59void rvt_mmap_init(struct rvt_dev_info *rdi)
  60{
  61        INIT_LIST_HEAD(&rdi->pending_mmaps);
  62        spin_lock_init(&rdi->pending_lock);
  63        rdi->mmap_offset = PAGE_SIZE;
  64        spin_lock_init(&rdi->mmap_offset_lock);
  65}
  66
  67/**
  68 * rvt_release_mmap_info - free mmap info structure
  69 * @ref: a pointer to the kref within struct rvt_mmap_info
  70 */
  71void rvt_release_mmap_info(struct kref *ref)
  72{
  73        struct rvt_mmap_info *ip =
  74                container_of(ref, struct rvt_mmap_info, ref);
  75        struct rvt_dev_info *rdi = ib_to_rvt(ip->context->device);
  76
  77        spin_lock_irq(&rdi->pending_lock);
  78        list_del(&ip->pending_mmaps);
  79        spin_unlock_irq(&rdi->pending_lock);
  80
  81        vfree(ip->obj);
  82        kfree(ip);
  83}
  84
  85static void rvt_vma_open(struct vm_area_struct *vma)
  86{
  87        struct rvt_mmap_info *ip = vma->vm_private_data;
  88
  89        kref_get(&ip->ref);
  90}
  91
  92static void rvt_vma_close(struct vm_area_struct *vma)
  93{
  94        struct rvt_mmap_info *ip = vma->vm_private_data;
  95
  96        kref_put(&ip->ref, rvt_release_mmap_info);
  97}
  98
  99static const struct vm_operations_struct rvt_vm_ops = {
 100        .open = rvt_vma_open,
 101        .close = rvt_vma_close,
 102};
 103
 104/**
 105 * rvt_mmap - create a new mmap region
 106 * @context: the IB user context of the process making the mmap() call
 107 * @vma: the VMA to be initialized
 108 *
 109 * Return: zero if the mmap is OK. Otherwise, return an errno.
 110 */
 111int rvt_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
 112{
 113        struct rvt_dev_info *rdi = ib_to_rvt(context->device);
 114        unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
 115        unsigned long size = vma->vm_end - vma->vm_start;
 116        struct rvt_mmap_info *ip, *pp;
 117        int ret = -EINVAL;
 118
 119        /*
 120         * Search the device's list of objects waiting for a mmap call.
 121         * Normally, this list is very short since a call to create a
 122         * CQ, QP, or SRQ is soon followed by a call to mmap().
 123         */
 124        spin_lock_irq(&rdi->pending_lock);
 125        list_for_each_entry_safe(ip, pp, &rdi->pending_mmaps,
 126                                 pending_mmaps) {
 127                /* Only the creator is allowed to mmap the object */
 128                if (context != ip->context || (__u64)offset != ip->offset)
 129                        continue;
 130                /* Don't allow a mmap larger than the object. */
 131                if (size > ip->size)
 132                        break;
 133
 134                list_del_init(&ip->pending_mmaps);
 135                spin_unlock_irq(&rdi->pending_lock);
 136
 137                ret = remap_vmalloc_range(vma, ip->obj, 0);
 138                if (ret)
 139                        goto done;
 140                vma->vm_ops = &rvt_vm_ops;
 141                vma->vm_private_data = ip;
 142                rvt_vma_open(vma);
 143                goto done;
 144        }
 145        spin_unlock_irq(&rdi->pending_lock);
 146done:
 147        return ret;
 148}
 149
 150/**
 151 * rvt_create_mmap_info - allocate information for hfi1_mmap
 152 * @rdi: rvt dev struct
 153 * @size: size in bytes to map
 154 * @udata: user data (must be valid!)
 155 * @obj: opaque pointer to a cq, wq etc
 156 *
 157 * Return: rvt_mmap struct on success
 158 */
 159struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size,
 160                                           struct ib_udata *udata, void *obj)
 161{
 162        struct rvt_mmap_info *ip;
 163
 164        if (!udata)
 165                return ERR_PTR(-EINVAL);
 166
 167        ip = kmalloc_node(sizeof(*ip), GFP_KERNEL, rdi->dparms.node);
 168        if (!ip)
 169                return ip;
 170
 171        size = PAGE_ALIGN(size);
 172
 173        spin_lock_irq(&rdi->mmap_offset_lock);
 174        if (rdi->mmap_offset == 0)
 175                rdi->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA);
 176        ip->offset = rdi->mmap_offset;
 177        rdi->mmap_offset += ALIGN(size, SHMLBA);
 178        spin_unlock_irq(&rdi->mmap_offset_lock);
 179
 180        INIT_LIST_HEAD(&ip->pending_mmaps);
 181        ip->size = size;
 182        ip->context =
 183                container_of(udata, struct uverbs_attr_bundle, driver_udata)
 184                        ->context;
 185        ip->obj = obj;
 186        kref_init(&ip->ref);
 187
 188        return ip;
 189}
 190
 191/**
 192 * rvt_update_mmap_info - update a mem map
 193 * @rdi: rvt dev struct
 194 * @ip: mmap info pointer
 195 * @size: size to grow by
 196 * @obj: opaque pointer to cq, wq, etc.
 197 */
 198void rvt_update_mmap_info(struct rvt_dev_info *rdi, struct rvt_mmap_info *ip,
 199                          u32 size, void *obj)
 200{
 201        size = PAGE_ALIGN(size);
 202
 203        spin_lock_irq(&rdi->mmap_offset_lock);
 204        if (rdi->mmap_offset == 0)
 205                rdi->mmap_offset = PAGE_SIZE;
 206        ip->offset = rdi->mmap_offset;
 207        rdi->mmap_offset += size;
 208        spin_unlock_irq(&rdi->mmap_offset_lock);
 209
 210        ip->size = size;
 211        ip->obj = obj;
 212}
 213