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1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB2/*3 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.4 * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.5 */6 7#include <linux/vmalloc.h>8#include <linux/mm.h>9#include <linux/errno.h>10#include <rdma/uverbs_ioctl.h>11 12#include "rxe.h"13#include "rxe_loc.h"14#include "rxe_queue.h"15 16void rxe_mmap_release(struct kref *ref)17{18 struct rxe_mmap_info *ip = container_of(ref,19 struct rxe_mmap_info, ref);20 struct rxe_dev *rxe = to_rdev(ip->context->device);21 22 spin_lock_bh(&rxe->pending_lock);23 24 if (!list_empty(&ip->pending_mmaps))25 list_del(&ip->pending_mmaps);26 27 spin_unlock_bh(&rxe->pending_lock);28 29 vfree(ip->obj); /* buf */30 kfree(ip);31}32 33/*34 * open and close keep track of how many times the memory region is mapped,35 * to avoid releasing it.36 */37static void rxe_vma_open(struct vm_area_struct *vma)38{39 struct rxe_mmap_info *ip = vma->vm_private_data;40 41 kref_get(&ip->ref);42}43 44static void rxe_vma_close(struct vm_area_struct *vma)45{46 struct rxe_mmap_info *ip = vma->vm_private_data;47 48 kref_put(&ip->ref, rxe_mmap_release);49}50 51static const struct vm_operations_struct rxe_vm_ops = {52 .open = rxe_vma_open,53 .close = rxe_vma_close,54};55 56/**57 * rxe_mmap - create a new mmap region58 * @context: the IB user context of the process making the mmap() call59 * @vma: the VMA to be initialized60 * Return zero if the mmap is OK. Otherwise, return an errno.61 */62int rxe_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)63{64 struct rxe_dev *rxe = to_rdev(context->device);65 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;66 unsigned long size = vma->vm_end - vma->vm_start;67 struct rxe_mmap_info *ip, *pp;68 int ret;69 70 /*71 * Search the device's list of objects waiting for a mmap call.72 * Normally, this list is very short since a call to create a73 * CQ, QP, or SRQ is soon followed by a call to mmap().74 */75 spin_lock_bh(&rxe->pending_lock);76 list_for_each_entry_safe(ip, pp, &rxe->pending_mmaps, pending_mmaps) {77 if (context != ip->context || (__u64)offset != ip->info.offset)78 continue;79 80 /* Don't allow a mmap larger than the object. */81 if (size > ip->info.size) {82 rxe_dbg_dev(rxe, "mmap region is larger than the object!\n");83 spin_unlock_bh(&rxe->pending_lock);84 ret = -EINVAL;85 goto done;86 }87 88 goto found_it;89 }90 rxe_dbg_dev(rxe, "unable to find pending mmap info\n");91 spin_unlock_bh(&rxe->pending_lock);92 ret = -EINVAL;93 goto done;94 95found_it:96 list_del_init(&ip->pending_mmaps);97 spin_unlock_bh(&rxe->pending_lock);98 99 ret = remap_vmalloc_range(vma, ip->obj, 0);100 if (ret) {101 rxe_dbg_dev(rxe, "err %d from remap_vmalloc_range\n", ret);102 goto done;103 }104 105 vma->vm_ops = &rxe_vm_ops;106 vma->vm_private_data = ip;107 rxe_vma_open(vma);108done:109 return ret;110}111 112/*113 * Allocate information for rxe_mmap114 */115struct rxe_mmap_info *rxe_create_mmap_info(struct rxe_dev *rxe, u32 size,116 struct ib_udata *udata, void *obj)117{118 struct rxe_mmap_info *ip;119 120 if (!udata)121 return ERR_PTR(-EINVAL);122 123 ip = kmalloc(sizeof(*ip), GFP_KERNEL);124 if (!ip)125 return ERR_PTR(-ENOMEM);126 127 size = PAGE_ALIGN(size);128 129 spin_lock_bh(&rxe->mmap_offset_lock);130 131 if (rxe->mmap_offset == 0)132 rxe->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA);133 134 ip->info.offset = rxe->mmap_offset;135 rxe->mmap_offset += ALIGN(size, SHMLBA);136 137 spin_unlock_bh(&rxe->mmap_offset_lock);138 139 INIT_LIST_HEAD(&ip->pending_mmaps);140 ip->info.size = size;141 ip->context =142 container_of(udata, struct uverbs_attr_bundle, driver_udata)143 ->context;144 ip->obj = obj;145 kref_init(&ip->ref);146 147 return ip;148}149