blob: 4d2238f3f3c8f62a6c80c726c582e41f0457003b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
/*
* Copyright(c) 2016 Intel Corporation.
*/
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <rdma/uverbs_ioctl.h>
#include "mmap.h"
/**
* rvt_mmap_init - init link list and lock for mem map
* @rdi: rvt dev struct
*/
void rvt_mmap_init(struct rvt_dev_info *rdi)
{
INIT_LIST_HEAD(&rdi->pending_mmaps);
spin_lock_init(&rdi->pending_lock);
rdi->mmap_offset = PAGE_SIZE;
spin_lock_init(&rdi->mmap_offset_lock);
}
/**
* rvt_release_mmap_info - free mmap info structure
* @ref: a pointer to the kref within struct rvt_mmap_info
*/
void rvt_release_mmap_info(struct kref *ref)
{
struct rvt_mmap_info *ip =
container_of(ref, struct rvt_mmap_info, ref);
struct rvt_dev_info *rdi = ib_to_rvt(ip->context->device);
spin_lock_irq(&rdi->pending_lock);
list_del(&ip->pending_mmaps);
spin_unlock_irq(&rdi->pending_lock);
vfree(ip->obj);
kfree(ip);
}
static void rvt_vma_open(struct vm_area_struct *vma)
{
struct rvt_mmap_info *ip = vma->vm_private_data;
kref_get(&ip->ref);
}
static void rvt_vma_close(struct vm_area_struct *vma)
{
struct rvt_mmap_info *ip = vma->vm_private_data;
kref_put(&ip->ref, rvt_release_mmap_info);
}
static const struct vm_operations_struct rvt_vm_ops = {
.open = rvt_vma_open,
.close = rvt_vma_close,
};
/**
* rvt_mmap - create a new mmap region
* @context: the IB user context of the process making the mmap() call
* @vma: the VMA to be initialized
*
* Return: zero if the mmap is OK. Otherwise, return an errno.
*/
int rvt_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
{
struct rvt_dev_info *rdi = ib_to_rvt(context->device);
unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
unsigned long size = vma->vm_end - vma->vm_start;
struct rvt_mmap_info *ip, *pp;
int ret = -EINVAL;
/*
* Search the device's list of objects waiting for a mmap call.
* Normally, this list is very short since a call to create a
* CQ, QP, or SRQ is soon followed by a call to mmap().
*/
spin_lock_irq(&rdi->pending_lock);
list_for_each_entry_safe(ip, pp, &rdi->pending_mmaps,
pending_mmaps) {
/* Only the creator is allowed to mmap the object */
if (context != ip->context || (__u64)offset != ip->offset)
continue;
/* Don't allow a mmap larger than the object. */
if (size > ip->size)
break;
list_del_init(&ip->pending_mmaps);
spin_unlock_irq(&rdi->pending_lock);
ret = remap_vmalloc_range(vma, ip->obj, 0);
if (ret)
goto done;
vma->vm_ops = &rvt_vm_ops;
vma->vm_private_data = ip;
rvt_vma_open(vma);
goto done;
}
spin_unlock_irq(&rdi->pending_lock);
done:
return ret;
}
/**
* rvt_create_mmap_info - allocate information for hfi1_mmap
* @rdi: rvt dev struct
* @size: size in bytes to map
* @udata: user data (must be valid!)
* @obj: opaque pointer to a cq, wq etc
*
* Return: rvt_mmap struct on success, ERR_PTR on failure
*/
struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size,
struct ib_udata *udata, void *obj)
{
struct rvt_mmap_info *ip;
if (!udata)
return ERR_PTR(-EINVAL);
ip = kmalloc_node(sizeof(*ip), GFP_KERNEL, rdi->dparms.node);
if (!ip)
return ERR_PTR(-ENOMEM);
size = PAGE_ALIGN(size);
spin_lock_irq(&rdi->mmap_offset_lock);
if (rdi->mmap_offset == 0)
rdi->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA);
ip->offset = rdi->mmap_offset;
rdi->mmap_offset += ALIGN(size, SHMLBA);
spin_unlock_irq(&rdi->mmap_offset_lock);
INIT_LIST_HEAD(&ip->pending_mmaps);
ip->size = size;
ip->context =
container_of(udata, struct uverbs_attr_bundle, driver_udata)
->context;
ip->obj = obj;
kref_init(&ip->ref);
return ip;
}
/**
* rvt_update_mmap_info - update a mem map
* @rdi: rvt dev struct
* @ip: mmap info pointer
* @size: size to grow by
* @obj: opaque pointer to cq, wq, etc.
*/
void rvt_update_mmap_info(struct rvt_dev_info *rdi, struct rvt_mmap_info *ip,
u32 size, void *obj)
{
size = PAGE_ALIGN(size);
spin_lock_irq(&rdi->mmap_offset_lock);
if (rdi->mmap_offset == 0)
rdi->mmap_offset = PAGE_SIZE;
ip->offset = rdi->mmap_offset;
rdi->mmap_offset += size;
spin_unlock_irq(&rdi->mmap_offset_lock);
ip->size = size;
ip->obj = obj;
}