// SPDX-License-Identifier: GPL-2.0
/*
* PCI Peer 2 Peer DMA support.
*
* Copyright (c) 2016-2018, Logan Gunthorpe
* Copyright (c) 2016-2017, Microsemi Corporation
* Copyright (c) 2017, Christoph Hellwig
* Copyright (c) 2018, Eideticom Inc.
*/
#define pr_fmt(fmt) "pci-p2pdma: " fmt
#include <linux/ctype.h>
#include <linux/dma-map-ops.h>
#include <linux/pci-p2pdma.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/genalloc.h>
#include <linux/memremap.h>
#include <linux/percpu-refcount.h>
#include <linux/random.h>
#include <linux/seq_buf.h>
#include <linux/xarray.h>
struct pci_p2pdma {
struct gen_pool *pool;
bool p2pmem_published;
struct xarray map_types;
struct p2pdma_provider mem[PCI_STD_NUM_BARS];
};
struct pci_p2pdma_pagemap {
struct dev_pagemap pgmap;
struct p2pdma_provider *mem;
};
static struct pci_p2pdma_pagemap *to_p2p_pgmap(struct dev_pagemap *pgmap)
{
return container_of(pgmap, struct pci_p2pdma_pagemap, pgmap);
}
static ssize_t size_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct pci_p2pdma *p2pdma;
size_t size = 0;
rcu_read_lock();
p2pdma = rcu_dereference(pdev->p2pdma);
if (p2pdma && p2pdma->pool)
size = gen_pool_size(p2pdma->pool);
rcu_read_unlock();
return sysfs_emit(buf, "%zd\n", size);
}
static DEVICE_ATTR_RO(size);
static ssize_t available_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct pci_p2pdma *p2pdma;
size_t avail = 0;
rcu_read_lock();
p2pdma = rcu_dereference(pdev->p2pdma);
if (p2pdma && p2pdma->pool)
avail = gen_pool_avail(p2pdma->pool);
rcu_read_unlock();
return sysfs_emit(buf, "%zd\n", avail);
}
static DEVICE_ATTR_RO(available);
static ssize_t published_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct pci_p2pdma *p2pdma;
bool published = false;
rcu_read_lock();
p2pdma = rcu_dereference(pdev->p2pdma);
if (p2pdma)
published = p2pdma->p2pmem_published;
rcu_read_unlock();
return sysfs_emit(buf, "%d\n", published);
}
static DEVICE_ATTR_RO(published);
static int p2pmem_alloc_mmap(struct file *filp, struct kobject *kobj,
const struct bin_attribute *attr, struct vm_area_struct *vma)
{
struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
size_t len =