path: root/arch/s390/pci/pci.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright IBM Corp. 2012
 *
 * Author(s):
 *   Jan Glauber <jang@linux.vnet.ibm.com>
 *
 * The System z PCI code is a rewrite from a prototype by
 * the following people (Kudoz!):
 *   Alexander Schmidt
 *   Christoph Raisch
 *   Hannes Hering
 *   Hoang-Nam Nguyen
 *   Jan-Bernd Themann
 *   Stefan Roscher
 *   Thomas Klein
 */

#define pr_fmt(fmt) "zpci: " fmt

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <linux/seq_file.h>
#include <linux/jump_label.h>
#include <linux/pci.h>
#include <linux/printk.h>
#include <linux/lockdep.h>
#include <linux/list_sort.h>

#include <asm/machine.h>
#include <asm/isc.h>
#include <asm/airq.h>
#include <asm/facility.h>
#include <asm/pci_insn.h>
#include <asm/pci_clp.h>
#include <asm/pci_dma.h>

#include "pci_bus.h"
#include "pci_iov.h"

/* list of all detected zpci devices */
static LIST_HEAD(zpci_list);
static DEFINE_SPINLOCK(zpci_list_lock);
static DEFINE_MUTEX(zpci_add_remove_lock);

static DECLARE_BITMAP(zpci_domain, ZPCI_DOMAIN_BITMAP_SIZE);
static DEFINE_SPINLOCK(zpci_domain_lock);

#define ZPCI_IOMAP_ENTRIES						\
	min(((unsigned long) ZPCI_NR_DEVICES * PCI_STD_NUM_BARS / 2),	\
	    ZPCI_IOMAP_MAX_ENTRIES)

unsigned int s390_pci_no_rid;

static DEFINE_SPINLOCK(zpci_iomap_lock);
static unsigned long *zpci_iomap_bitmap;
struct zpci_iomap_entry *zpci_iomap_start;
EXPORT_SYMBOL_GPL(zpci_iomap_start);

DEFINE_STATIC_KEY_FALSE(have_mio);

static struct kmem_cache *zdev_fmb_cache;

/* AEN structures that must be preserved over KVM module re-insertion */
union zpci_sic_iib *zpci_aipb;
EXPORT_SYMBOL_GPL(zpci_aipb);
struct airq_iv *zpci_aif_sbv;
EXPORT_SYMBOL_GPL(zpci_aif_sbv);

void zpci_zdev_put(struct zpci_dev *zdev)
{
	if (!zdev)
		return;
	mutex_lock(&zpci_add_remove_lock);
	kref_put_lock(&zdev->kref, zpci_release_device, &zpci_list_lock);
	mutex_unlock(&zpci_add_remove_lock);
}

struct zpci_dev *get_zdev_by_fid(u32 fid)
{
	struct zpci_dev *tmp, *zdev = NULL;

	spin_lock(&zpci_list_lock);
	list_for_each_entry(tmp, &zpci_list, entry) {
		if (tmp->fid == fid) {
			zdev = tmp;
			zpci_zdev_get(zdev);
			break;
		}
	}
	spin_unlock(&zpci_list_lock);
	return zdev;
}

void zpci_remove_reserved_devices(void)
{
	struct zpci_dev *tmp, *zdev;
	enum zpci_state state;
	LIST_HEAD(remove);

	spin_lock(&zpci_list_lock);
	list_for_each_entry_safe(zdev, tmp, &zpci_list, entry) {
		if (zdev->state == ZPCI_FN_STATE_STANDBY &&
		    !clp_get_state(zdev->fid, &state) &&
		    state == ZPCI_FN_STATE_RESERVED)
			list_move_tail(&zdev->entry, &remove);
	}
	spin_unlock(&zpci_list_lock);

	list_for_each_entry_safe(zdev, tmp, &remove, entry)
		zpci_device_reserved(zdev);
}

int pci_domain_nr(struct pci_bus *