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  */
  59 void 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  */
  71 void 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
  85 static 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
  92 static 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
  99 static 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  */
 111 int 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);
 146 done:
 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  */
 159 struct 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  */
 198 void 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 }