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1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause2/*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 map14 * @rdi: rvt dev struct15 */16void 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 structure26 * @ref: a pointer to the kref within struct rvt_mmap_info27 */28void 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 42static 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 49static 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 56static 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 region63 * @context: the IB user context of the process making the mmap() call64 * @vma: the VMA to be initialized65 *66 * Return: zero if the mmap is OK. Otherwise, return an errno.67 */68int 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 a79	 * 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);103done:104	return ret;105}106 107/**108 * rvt_create_mmap_info - allocate information for hfi1_mmap109 * @rdi: rvt dev struct110 * @size: size in bytes to map111 * @udata: user data (must be valid!)112 * @obj: opaque pointer to a cq, wq etc113 *114 * Return: rvt_mmap struct on success, ERR_PTR on failure115 */116struct 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 map150 * @rdi: rvt dev struct151 * @ip: mmap info pointer152 * @size: size to grow by153 * @obj: opaque pointer to cq, wq, etc.154 */155void 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