linux-imx

// 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/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>

​

struct pci_p2pdma {

    struct percpu_ref devmap_ref;

    struct completion devmap_ref_done;

    struct gen_pool *pool;

    bool p2pmem_published;

};

​

static ssize_t size_show(struct device *dev, struct device_attribute *attr,

             char *buf)

{

    struct pci_dev *pdev = to_pci_dev(dev);

    size_t size = 0;

​

    if (pdev->p2pdma->pool)

        size = gen_pool_size(pdev->p2pdma->pool);

​

    return snprintf(buf, PAGE_SIZE, "%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);

    size_t avail = 0;

​

    if (pdev->p2pdma->pool)

        avail = gen_pool_avail(pdev->p2pdma->pool);

​

    return snprintf(buf, PAGE_SIZE, "%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);

​

    return snprintf(buf, PAGE_SIZE, "%d\n",

            pdev->p2pdma->p2pmem_published);

}

static DEVICE_ATTR_RO(published);