kernel_samsung_a34x-permissive/drivers/iommu/intel-pasid.c

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// SPDX-License-Identifier: GPL-2.0
/**
* intel-pasid.c - PASID idr, table and entry manipulation
*
* Copyright (C) 2018 Intel Corporation
*
* Author: Lu Baolu <baolu.lu@linux.intel.com>
*/
#define pr_fmt(fmt) "DMAR: " fmt
#include <linux/dmar.h>
#include <linux/intel-iommu.h>
#include <linux/iommu.h>
#include <linux/memory.h>
#include <linux/pci.h>
#include <linux/pci-ats.h>
#include <linux/spinlock.h>
#include "intel-pasid.h"
/*
* Intel IOMMU system wide PASID name space:
*/
static DEFINE_SPINLOCK(pasid_lock);
u32 intel_pasid_max_id = PASID_MAX;
static DEFINE_IDR(pasid_idr);
int intel_pasid_alloc_id(void *ptr, int start, int end, gfp_t gfp)
{
int ret, min, max;
min = max_t(int, start, PASID_MIN);
max = min_t(int, end, intel_pasid_max_id);
WARN_ON(in_interrupt());
idr_preload(gfp);
spin_lock(&pasid_lock);
ret = idr_alloc(&pasid_idr, ptr, min, max, GFP_ATOMIC);
spin_unlock(&pasid_lock);
idr_preload_end();
return ret;
}
void intel_pasid_free_id(int pasid)
{
spin_lock(&pasid_lock);
idr_remove(&pasid_idr, pasid);
spin_unlock(&pasid_lock);
}
void *intel_pasid_lookup_id(int pasid)
{
void *p;
spin_lock(&pasid_lock);
p = idr_find(&pasid_idr, pasid);
spin_unlock(&pasid_lock);
return p;
}
/*
* Per device pasid table management:
*/
static inline void
device_attach_pasid_table(struct device_domain_info *info,
struct pasid_table *pasid_table)
{
info->pasid_table = pasid_table;
list_add(&info->table, &pasid_table->dev);
}
static inline void
device_detach_pasid_table(struct device_domain_info *info,
struct pasid_table *pasid_table)
{
info->pasid_table = NULL;
list_del(&info->table);
}
struct pasid_table_opaque {
struct pasid_table **pasid_table;
int segment;
int bus;
int devfn;
};
static int search_pasid_table(struct device_domain_info *info, void *opaque)
{
struct pasid_table_opaque *data = opaque;
if (info->iommu->segment == data->segment &&
info->bus == data->bus &&
info->devfn == data->devfn &&
info->pasid_table) {
*data->pasid_table = info->pasid_table;
return 1;
}
return 0;
}
static int get_alias_pasid_table(struct pci_dev *pdev, u16 alias, void *opaque)
{
struct pasid_table_opaque *data = opaque;
data->segment = pci_domain_nr(pdev->bus);
data->bus = PCI_BUS_NUM(alias);
data->devfn = alias & 0xff;
return for_each_device_domain(&search_pasid_table, data);
}
/*
* Allocate a pasid table for @dev. It should be called in a
* single-thread context.
*/
int intel_pasid_alloc_table(struct device *dev)
{
struct device_domain_info *info;
struct pasid_table *pasid_table;
struct pasid_table_opaque data;
struct page *pages;
size_t size, count;
int ret, order;
info = dev->archdata.iommu;
if (WARN_ON(!info || !dev_is_pci(dev) ||
!info->pasid_supported || info->pasid_table))
return -EINVAL;
/* DMA alias device already has a pasid table, use it: */
data.pasid_table = &pasid_table;
ret = pci_for_each_dma_alias(to_pci_dev(dev),
&get_alias_pasid_table, &data);
if (ret)
goto attach_out;
pasid_table = kzalloc(sizeof(*pasid_table), GFP_ATOMIC);
if (!pasid_table)
return -ENOMEM;
INIT_LIST_HEAD(&pasid_table->dev);
size = sizeof(struct pasid_entry);
count = min_t(int, pci_max_pasids(to_pci_dev(dev)), intel_pasid_max_id);
order = get_order(size * count);
pages = alloc_pages_node(info->iommu->node,
GFP_ATOMIC | __GFP_ZERO,
order);
if (!pages)
return -ENOMEM;
pasid_table->table = page_address(pages);
pasid_table->order = order;
pasid_table->max_pasid = count;
attach_out:
device_attach_pasid_table(info, pasid_table);
return 0;
}
void intel_pasid_free_table(struct device *dev)
{
struct device_domain_info *info;
struct pasid_table *pasid_table;
info = dev->archdata.iommu;
if (!info || !dev_is_pci(dev) ||
!info->pasid_supported || !info->pasid_table)
return;
pasid_table = info->pasid_table;
device_detach_pasid_table(info, pasid_table);
if (!list_empty(&pasid_table->dev))
return;
free_pages((unsigned long)pasid_table->table, pasid_table->order);
kfree(pasid_table);
}
struct pasid_table *intel_pasid_get_table(struct device *dev)
{
struct device_domain_info *info;
info = dev->archdata.iommu;
if (!info)
return NULL;
return info->pasid_table;
}
int intel_pasid_get_dev_max_id(struct device *dev)
{
struct device_domain_info *info;
info = dev->archdata.iommu;
if (!info || !info->pasid_table)
return 0;
return info->pasid_table->max_pasid;
}
struct pasid_entry *intel_pasid_get_entry(struct device *dev, int pasid)
{
struct pasid_table *pasid_table;
struct pasid_entry *entries;
pasid_table = intel_pasid_get_table(dev);
if (WARN_ON(!pasid_table || pasid < 0 ||
pasid >= intel_pasid_get_dev_max_id(dev)))
return NULL;
entries = pasid_table->table;
return &entries[pasid];
}
/*
* Interfaces for PASID table entry manipulation:
*/
static inline void pasid_clear_entry(struct pasid_entry *pe)
{
WRITE_ONCE(pe->val, 0);
}
void intel_pasid_clear_entry(struct device *dev, int pasid)
{
struct pasid_entry *pe;
pe = intel_pasid_get_entry(dev, pasid);
if (WARN_ON(!pe))
return;
pasid_clear_entry(pe);
}