/*
* Copyright (C) 2010-2012 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
*/
#include <linux/mmu_notifier.h>
#include <linux/amd-iommu.h>
#include <linux/mm_types.h>
#include <linux/profile.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/iommu.h>
#include <linux/wait.h>
#include <linux/pci.h>
#include <linux/gfp.h>
#include "amd_iommu_types.h"
#include "amd_iommu_proto.h"
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Joerg Roedel <joerg.roedel@amd.com>");
#define MAX_DEVICES 0x10000
#define PRI_QUEUE_SIZE 512
struct pri_queue {
atomic_t inflight;
bool finish;
int status;
};
struct pasid_state {
struct list_head list; /* For global state-list */
atomic_t count; /* Reference count */
struct task_struct *task; /* Task bound to this PASID */
struct mm_struct *mm; /* mm_struct for the faults */
struct mmu_notifier mn; /* mmu_otifier handle */
struct pri_queue pri[PRI_QUEUE_SIZE]; /* PRI tag states */
struct device_state *device_state; /* Link to our device_state */
int pasid; /* PASID index */
spinlock_t lock; /* Protect pri_queues */
wait_queue_head_t wq; /* To wait for count == 0 */
};
struct device_state {
atomic_t count;
struct pci_dev *pdev;
struct pasid_state **states;
struct iommu_domain *domain;
int pasid_levels;
int max_pasids;
amd_iommu_invalid_ppr_cb inv_ppr_cb;
amd_iommu_invalidate_ctx inv_ctx_cb;
spinlock_t lock;
wait_queue_head_t wq;
};
struct fault {
struct work_struct work;
struct device_state *dev_state;
struct pasid_state *state;
struct mm_struct *mm;
u64 address;
u16 devid;
u16 pasid;
u16 tag;
u16 finish;
u16 flags;
};
struct device_state **state_table;
static spinlock_t state_lock;
/* List and lock for all pasid_states */
static LIST_HEAD(pasid_state_list);
static DEFINE_SPINLOCK(ps_lock);
static struct workqueue_struct *iommu_wq;
/*
* Empty page table - Used between
* mmu_notifier_invalidate_range_start and
* mmu_notifier_invalidate_range_end
*/
static u64 *empty_page_table;
static void free_pasid_states(struct device_state *dev_state);
static void unbind_pasid(struct device_state *dev_state, int pasid);
static int task_exit(struct notifier_block *nb, unsigned long e, void *data);
static u16 device_id(struct pci_dev *pdev)
{
u16 devid;
devid = pdev->bus->number;
devid = (devid << 8) | pdev->devfn;
return devid;
}
static struct device_state *get_device_state(u16 devid)
{
struct device_state *dev_state;
unsigned long flags;
spin_lock_irqsave(&state_lock, flags);
dev_state = state_table[devid];
if (dev_state != NULL)
atomic_inc(&dev_state->count);
spin_unlock_irqrestore(&state_lock, flags);
return dev_state;
}
static void free_device_state(struct device_state *dev_state)
{
/*
* First detach device from domain - No more PRI requests will arrive
* from that device after it is unbound from the IOMMUv2 domain.
*/
iommu_detach_device(dev_state->domain, &dev_state->pdev->dev);
/* Everything is down now, free the IOMMUv2 domain */
iommu_domain_free(dev_state->domain);
/* Finally get rid of the device-state */
kfree(dev_state);
}
static void put_device_state(struct device_state *dev_state)
{
if (atomic_dec_and_test(&dev_state->count))
wake_up(&dev_state->wq);
}
static void put_device_state_wait(struct device_state *dev_state)
{
DEFINE_WAIT(wait);
prepare_to_wait(&dev_state->wq, &wait, TASK_UNINTERRUPTIBLE);
if (!atomic_dec_and_test(&dev_state->count))
schedule();
finish_wait(&dev_state->wq, &wait);
free_device_state(dev_state);
}
static struct notifier_block profile_nb = {
.notifier_call = task_exit,
};
static void link_pasid_state(struct pasid_state *pasid_state)
{
spin_lock(&ps_lock);
list_add_tail(&pasid_state->list, &pasid_state_list);
spin_unlock(&ps_lock);
}
static void __unlink_pasid_state(