/*
* Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
* Author: Joerg Roedel <joerg.roedel@amd.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/bug.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/iommu.h>
static ssize_t show_iommu_group(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned int groupid;
if (iommu_device_group(dev, &groupid))
return 0;
return sprintf(buf, "%u", groupid);
}
static DEVICE_ATTR(iommu_group, S_IRUGO, show_iommu_group, NULL);
static int add_iommu_group(struct device *dev, void *data)
{
unsigned int groupid;
if (iommu_device_group(dev, &groupid) == 0)
return device_create_file(dev, &dev_attr_iommu_group);
return 0;
}
static int remove_iommu_group(struct device *dev)
{
unsigned int groupid;
if (iommu_device_group(dev, &groupid) == 0)
device_remove_file(dev, &dev_attr_iommu_group);
return 0;
}
static int iommu_device_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
if (action == BUS_NOTIFY_ADD_DEVICE)
return add_iommu_group(dev, NULL);
else if (action == BUS_NOTIFY_DEL_DEVICE)
return remove_iommu_group(dev);
return 0;
}
static struct notifier_block iommu_device_nb = {
.notifier_call = iommu_device_notifier,
};
static void iommu_bus_init(struct bus_type *bus, struct iommu_ops *ops)
{
bus_register_notifier(bus, &iommu_device_nb);
bus_for_each_dev(bus, NULL, NULL, add_iommu_group);
}
/**
* bus_set_iommu - set iommu-callbacks for the bus
* @bus: bus.
* @ops: the callbacks provided by the iommu-driver
*
* This function is called by an iommu driver to set the iommu methods
* used for a particular bus. Drivers for devices on that bus can use
* the iommu-api after these ops are registered.
* This special function is needed because IOMMUs are usually devices on
* the bus itself, so the iommu drivers are not initialized when the bus
* is set up. With this function the iommu-driver can set the iommu-ops
* afterwards.
*/
int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops)
{
if (bus->iommu_ops != NULL)
return -EBUSY;
bus->iommu_ops = ops;
/* Do IOMMU specific setup for this bus-type */
iommu_bus_init(bus, ops);
return 0;
}
EXPORT_SYMBOL_GPL(bus_set_iommu);
bool iommu_present(struct bus_type *bus)
{
return bus->iommu_ops != NULL;
}
EXPORT_SYMBOL_GPL(iommu_present);
/**
* iommu_set_fault_handler() - set a fault handler for an iommu domain
* @domain: iommu domain
* @handler: fault handler
*
* This function should be used by IOMMU users which want to be notified
* whenever an IOMMU fault happens.
*
* The fault handler itself should return 0 on success, and an appropriate
* error code otherwise.
*/
void iommu_set_fault_handler(struct iommu_domain *domain,
iommu_fault_handler_t handler)
{
BUG_ON(!domain);
domain->handler = handler;
}
EXPORT_SYMBOL_GPL(iommu_set_fault_handler);
struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
{
struct iommu_domain *domain;
int ret;
if (bus == NULL || bus->iommu_ops == NULL)
return NULL;
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!domain)
return NULL;
domain->ops = bus->iommu_ops;
ret = domain->ops->domain_init(domain);
if (ret)
goto out_free;
return domain;
out_free:
kfree(domain);
return NULL;
}
EXPORT_SYMBOL_GPL(iommu_domain_alloc);
void iommu_domain_free(struct iommu_domain *domain)
{
if (likely(domain->ops->domain_destroy != NULL))
domain->ops->domain_destroy(domain);
kfree(domain);
}
EXPORT_SYMBOL_GPL(iommu_domain_free);
int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
{
if (unlikely(domain->ops->attach_dev == NULL))
return -ENODEV;
return domain->ops->attach_dev(domain, dev);
}
EXPORT_SYMBOL_GPL(iommu_attach_device);
void iommu_detach_device(struct iommu_domain *domain, struct device *dev)
{
if (unlikely(domain->ops->detach_dev == NULL))
return;
domain->ops->detach_dev(domain, dev);
}
EXPORT_SYMBOL_GPL(iommu_detach_device);
phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
unsigned long iova)
{
if (unlikely(domain->ops->iova_to_phys == NULL))
return 0;
return domain->ops->iova_to_phys(domain, iova);
}
EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
int iommu_domain_has_cap(struct iommu_domain *domain,
unsigned long cap)
{
if (unlikely(domain->ops->domain_has_cap == NULL))
return 0;
return domain->ops->domain_has_cap(domain, cap);
}
EXPORT_SYMBOL_GPL(iommu_domain_has_cap);
int iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
unsigned long orig_iova = iova;
unsigned int min_pagesz;
size_t orig_size = size;
int ret = 0;
if (unlikely(domain->ops->map == NULL))
return -ENODEV;
/* find out the minimum page size supported */
min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
/*
* both the virtual address and the physical one, as well as
* the size of the mapping, must be aligned (at least) to the
* size of the smallest page supported by the hardware
*/
if (!IS_ALIGNED(iova | paddr | size, min_pagesz)) {
pr_err("unaligned: iova 0x%lx pa 0x%lx size 0x%lx min_pagesz "
"0x%x\n", iova, (unsigned long)paddr,
(unsigned long)size, min_pagesz);
return -EINVAL;
}
pr_debug("map: iova 0x%lx pa 0x%lx size 0x%lx\n", iova,
(unsigned long)paddr, (unsigned long)size);
while (size) {
unsigned long pgsize, addr_merge = iova | paddr;
unsigned int pgsize_idx;
/* Max page size that still fits into 'size' */
pgsize_idx = __fls(size);
/* need to consider alignment requirements ? */
if (likely(addr_merge)) {
/* Max page size allowed by both iova and paddr */
unsigned int align_pgsize_idx = __ffs(addr_merge);
pgsize_idx = min(pgsize_idx, align_pgsize_idx);
}
/* build a mask of acceptable page sizes */
pgsize = (1UL << (pgsize_idx + 1)) - 1;
/* throw away page sizes not supported by the hardware */
pgsize &= domain->ops->pgsize_bitmap;
/* make sure we're still sane */
BUG_ON(!pgsize);
/* pick the biggest page */
pgsize_idx = __fls(pgsize);
pgsize = 1UL << pgsize_idx;
pr_debug("mapping: iova 0x%lx pa 0x%lx pgsize %lu\n", iova,
(unsigned long)paddr, pgsize);
ret = domain->ops->map(domain, iova, paddr, pgsize, prot);
if (ret)
break;
iova += pgsize;
paddr += pgsize;
size -= pgsize;
}
/* unroll mapping in case something went wrong */
if (ret)
iommu_unmap(domain, orig_iova, orig_size - size);
return ret;
}
EXPORT_SYMBOL_GPL(iommu_map);
size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size)
{
size_t unmapped_page, unmapped = 0;
unsigned int min_pagesz;
if (unlikely(domain->ops->unmap == NULL))
return -ENODEV;
/* find out the minimum page size supported */
min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
/*
* The virtual address, as well as the size of the mapping, must be
* aligned (at least) to the size of the smallest page supported
* by the hardware
*/
if (!IS_ALIGNED(iova | size, min_pagesz)) {
pr_err("unaligned: iova 0x%lx size 0x%lx min_pagesz 0x%x\n",
iova, (unsigned long)size, min_pagesz);
return -EINVAL;
}
pr_debug("unmap this: iova 0x%lx size 0x%lx\n", iova,
(unsigned long)size);
/*
* Keep iterating until we either unmap 'size' bytes (or more)
* or we hit an area that isn't mapped.
*/
while (unmapped < size) {
size_t left = size - unmapped;
unmapped_page = domain->ops->unmap(domain, iova, left);
if (!unmapped_page)
break;
pr_debug("unmapped: iova 0x%lx size %lx\n", iova,
(unsigned long)unmapped_page);
iova += unmapped_page;
unmapped += unmapped_page;
}
return unmapped;
}
EXPORT_SYMBOL_GPL(iommu_unmap);
int iommu_device_group(struct device *dev, unsigned int *groupid)
{
if (iommu_present(dev->bus) && dev->bus->iommu_ops->device_group)
return dev->bus->iommu_ops->device_group(dev, groupid);
return -ENODEV;
}
EXPORT_SYMBOL_GPL(iommu_device_group);
