1 // SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause 2 /* 3 * Copyright(c) 2016 Intel Corporation. 4 */ 5 6 #include <linux/slab.h> 7 #include <linux/vmalloc.h> 8 #include <linux/mm.h> 9 #include <rdma/uverbs_ioctl.h> 10 #include "mmap.h" 11 12 /** 13 * rvt_mmap_init - init link list and lock for mem map 14 * @rdi: rvt dev struct 15 */ 16 void rvt_mmap_init(struct rvt_dev_info *rdi) 17 { 18 INIT_LIST_HEAD(&rdi->pending_mmaps); 19 spin_lock_init(&rdi->pending_lock); 20 rdi->mmap_offset = PAGE_SIZE; 21 spin_lock_init(&rdi->mmap_offset_lock); 22 } 23 24 /** 25 * rvt_release_mmap_info - free mmap info structure 26 * @ref: a pointer to the kref within struct rvt_mmap_info 27 */ 28 void rvt_release_mmap_info(struct kref *ref) 29 { 30 struct rvt_mmap_info *ip = 31 container_of(ref, struct rvt_mmap_info, ref); 32 struct rvt_dev_info *rdi = ib_to_rvt(ip->context->device); 33 34 spin_lock_irq(&rdi->pending_lock); 35 list_del(&ip->pending_mmaps); 36 spin_unlock_irq(&rdi->pending_lock); 37 38 vfree(ip->obj); 39 kfree(ip); 40 } 41 42 static void rvt_vma_open(struct vm_area_struct *vma) 43 { 44 struct rvt_mmap_info *ip = vma->vm_private_data; 45 46 kref_get(&ip->ref); 47 } 48 49 static void rvt_vma_close(struct vm_area_struct *vma) 50 { 51 struct rvt_mmap_info *ip = vma->vm_private_data; 52 53 kref_put(&ip->ref, rvt_release_mmap_info); 54 } 55 56 static const struct vm_operations_struct rvt_vm_ops = { 57 .open = rvt_vma_open, 58 .close = rvt_vma_close, 59 }; 60 61 /** 62 * rvt_mmap - create a new mmap region 63 * @context: the IB user context of the process making the mmap() call 64 * @vma: the VMA to be initialized 65 * 66 * Return: zero if the mmap is OK. Otherwise, return an errno. 67 */ 68 int rvt_mmap(struct ib_ucontext *context, struct vm_area_struct *vma) 69 { 70 struct rvt_dev_info *rdi = ib_to_rvt(context->device); 71 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; 72 unsigned long size = vma->vm_end - vma->vm_start; 73 struct rvt_mmap_info *ip, *pp; 74 int ret = -EINVAL; 75 76 /* 77 * Search the device's list of objects waiting for a mmap call. 78 * Normally, this list is very short since a call to create a 79 * CQ, QP, or SRQ is soon followed by a call to mmap(). 80 */ 81 spin_lock_irq(&rdi->pending_lock); 82 list_for_each_entry_safe(ip, pp, &rdi->pending_mmaps, 83 pending_mmaps) { 84 /* Only the creator is allowed to mmap the object */ 85 if (context != ip->context || (__u64)offset != ip->offset) 86 continue; 87 /* Don't allow a mmap larger than the object. */ 88 if (size > ip->size) 89 break; 90 91 list_del_init(&ip->pending_mmaps); 92 spin_unlock_irq(&rdi->pending_lock); 93 94 ret = remap_vmalloc_range(vma, ip->obj, 0); 95 if (ret) 96 goto done; 97 vma->vm_ops = &rvt_vm_ops; 98 vma->vm_private_data = ip; 99 rvt_vma_open(vma); 100 goto done; 101 } 102 spin_unlock_irq(&rdi->pending_lock); 103 done: 104 return ret; 105 } 106 107 /** 108 * rvt_create_mmap_info - allocate information for hfi1_mmap 109 * @rdi: rvt dev struct 110 * @size: size in bytes to map 111 * @udata: user data (must be valid!) 112 * @obj: opaque pointer to a cq, wq etc 113 * 114 * Return: rvt_mmap struct on success, ERR_PTR on failure 115 */ 116 struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size, 117 struct ib_udata *udata, void *obj) 118 { 119 struct rvt_mmap_info *ip; 120 121 if (!udata) 122 return ERR_PTR(-EINVAL); 123 124 ip = kmalloc_node(sizeof(*ip), GFP_KERNEL, rdi->dparms.node); 125 if (!ip) 126 return ERR_PTR(-ENOMEM); 127 128 size = PAGE_ALIGN(size); 129 130 spin_lock_irq(&rdi->mmap_offset_lock); 131 if (rdi->mmap_offset == 0) 132 rdi->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA); 133 ip->offset = rdi->mmap_offset; 134 rdi->mmap_offset += ALIGN(size, SHMLBA); 135 spin_unlock_irq(&rdi->mmap_offset_lock); 136 137 INIT_LIST_HEAD(&ip->pending_mmaps); 138 ip->size = size; 139 ip->context = 140 container_of(udata, struct uverbs_attr_bundle, driver_udata) 141 ->context; 142 ip->obj = obj; 143 kref_init(&ip->ref); 144 145 return ip; 146 } 147 148 /** 149 * rvt_update_mmap_info - update a mem map 150 * @rdi: rvt dev struct 151 * @ip: mmap info pointer 152 * @size: size to grow by 153 * @obj: opaque pointer to cq, wq, etc. 154 */ 155 void rvt_update_mmap_info(struct rvt_dev_info *rdi, struct rvt_mmap_info *ip, 156 u32 size, void *obj) 157 { 158 size = PAGE_ALIGN(size); 159 160 spin_lock_irq(&rdi->mmap_offset_lock); 161 if (rdi->mmap_offset == 0) 162 rdi->mmap_offset = PAGE_SIZE; 163 ip->offset = rdi->mmap_offset; 164 rdi->mmap_offset += size; 165 spin_unlock_irq(&rdi->mmap_offset_lock); 166 167 ip->size = size; 168 ip->obj = obj; 169 } 170