diff options
Diffstat (limited to 'drivers/iommu/amd/iommu_v2.c')
| -rw-r--r-- | drivers/iommu/amd/iommu_v2.c | 981 |
1 files changed, 981 insertions, 0 deletions
diff --git a/drivers/iommu/amd/iommu_v2.c b/drivers/iommu/amd/iommu_v2.c new file mode 100644 index 000000000000..e4b025c5637c --- /dev/null +++ b/drivers/iommu/amd/iommu_v2.c @@ -0,0 +1,981 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2010-2012 Advanced Micro Devices, Inc. + * Author: Joerg Roedel <jroedel@suse.de> + */ + +#define pr_fmt(fmt) "AMD-Vi: " fmt + +#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/sched/mm.h> +#include <linux/wait.h> +#include <linux/pci.h> +#include <linux/gfp.h> + +#include "amd_iommu.h" + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Joerg Roedel <jroedel@suse.de>"); + +#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 */ + unsigned mmu_notifier_count; /* Counting nested mmu_notifier + calls */ + struct mm_struct *mm; /* mm_struct for the faults */ + struct mmu_notifier mn; /* mmu_notifier 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 */ + bool invalid; /* Used during setup and + teardown of the pasid */ + spinlock_t lock; /* Protect pri_queues and + mmu_notifer_count */ + wait_queue_head_t wq; /* To wait for count == 0 */ +}; + +struct device_state { + struct list_head list; + u16 devid; + 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; +}; + +static LIST_HEAD(state_list); +static spinlock_t state_lock; + +static struct workqueue_struct *iommu_wq; + +static void free_pasid_states(struct device_state *dev_state); + +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; + + list_for_each_entry(dev_state, &state_list, list) { + if (dev_state->devid == devid) + return dev_state; + } + + return NULL; +} + +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 = __get_device_state(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) +{ + struct iommu_group *group; + + /* + * First detach device from domain - No more PRI requests will arrive + * from that device after it is unbound from the IOMMUv2 domain. + */ + group = iommu_group_get(&dev_state->pdev->dev); + if (WARN_ON(!group)) + return; + + iommu_detach_group(dev_state->domain, group); + + iommu_group_put(group); + + /* 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); +} + +/* Must be called under dev_state->lock */ +static struct pasid_state **__get_pasid_state_ptr(struct device_state *dev_state, + int pasid, bool alloc) +{ + struct pasid_state **root, **ptr; + int level, index; + + level = dev_state->pasid_levels; + root = dev_state->states; + + while (true) { + + index = (pasid >> (9 * level)) & 0x1ff; + ptr = &root[index]; + + if (level == 0) + break; + + if (*ptr == NULL) { + if (!alloc) + return NULL; + + *ptr = (void *)get_zeroed_page(GFP_ATOMIC); + if (*ptr == NULL) + return NULL; + } + + root = (struct pasid_state **)*ptr; + level -= 1; + } + + return ptr; +} + +static int set_pasid_state(struct device_state *dev_state, + struct pasid_state *pasid_state, + int pasid) +{ + struct pasid_state **ptr; + unsigned long flags; + int ret; + + spin_lock_irqsave(&dev_state->lock, flags); + ptr = __get_pasid_state_ptr(dev_state, pasid, true); + + ret = -ENOMEM; + if (ptr == NULL) + goto out_unlock; + + ret = -ENOMEM; + if (*ptr != NULL) + goto out_unlock; + + *ptr = pasid_state; + + ret = 0; + +out_unlock: + spin_unlock_irqrestore(&dev_state->lock, flags); + + return ret; +} + +static void clear_pasid_state(struct device_state *dev_state, int pasid) +{ + struct pasid_state **ptr; + unsigned long flags; + + spin_lock_irqsave(&dev_state->lock, flags); + ptr = __get_pasid_state_ptr(dev_state, pasid, true); + + if (ptr == NULL) + goto out_unlock; + + *ptr = NULL; + +out_unlock: + spin_unlock_irqrestore(&dev_state->lock, flags); +} + +static struct pasid_state *get_pasid_state(struct device_state *dev_state, + int pasid) +{ + struct pasid_state **ptr, *ret = NULL; + unsigned long flags; + + spin_lock_irqsave(&dev_state->lock, flags); + ptr = __get_pasid_state_ptr(dev_state, pasid, false); + + if (ptr == NULL) + goto out_unlock; + + ret = *ptr; + if (ret) + atomic_inc(&ret->count); + +out_unlock: + spin_unlock_irqrestore(&dev_state->lock, flags); + + return ret; +} + +static void free_pasid_state(struct pasid_state *pasid_state) +{ + kfree(pasid_state); +} + +static void put_pasid_state(struct pasid_state *pasid_state) +{ + if (atomic_dec_and_test(&pasid_state->count)) + wake_up(&pasid_state->wq); +} + +static void put_pasid_state_wait(struct pasid_state *pasid_state) +{ + atomic_dec(&pasid_state->count); + wait_event(pasid_state->wq, !atomic_read(&pasid_state->count)); + free_pasid_state(pasid_state); +} + +static void unbind_pasid(struct pasid_state *pasid_state) +{ + struct iommu_domain *domain; + + domain = pasid_state->device_state->domain; + + /* + * Mark pasid_state as invalid, no more faults will we added to the + * work queue after this is visible everywhere. + */ + pasid_state->invalid = true; + + /* Make sure this is visible */ + smp_wmb(); + + /* After this the device/pasid can't access the mm anymore */ + amd_iommu_domain_clear_gcr3(domain, pasid_state->pasid); + + /* Make sure no more pending faults are in the queue */ + flush_workqueue(iommu_wq); +} + +static void free_pasid_states_level1(struct pasid_state **tbl) +{ + int i; + + for (i = 0; i < 512; ++i) { + if (tbl[i] == NULL) + continue; + + free_page((unsigned long)tbl[i]); + } +} + +static void free_pasid_states_level2(struct pasid_state **tbl) +{ + struct pasid_state **ptr; + int i; + + for (i = 0; i < 512; ++i) { + if (tbl[i] == NULL) + continue; + + ptr = (struct pasid_state **)tbl[i]; + free_pasid_states_level1(ptr); + } +} + +static void free_pasid_states(struct device_state *dev_state) +{ + struct pasid_state *pasid_state; + int i; + + for (i = 0; i < dev_state->max_pasids; ++i) { + pasid_state = get_pasid_state(dev_state, i); + if (pasid_state == NULL) + continue; + + put_pasid_state(pasid_state); + + /* + * This will call the mn_release function and + * unbind the PASID + */ + mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm); + + put_pasid_state_wait(pasid_state); /* Reference taken in + amd_iommu_bind_pasid */ + + /* Drop reference taken in amd_iommu_bind_pasid */ + put_device_state(dev_state); + } + + if (dev_state->pasid_levels == 2) + free_pasid_states_level2(dev_state->states); + else if (dev_state->pasid_levels == 1) + free_pasid_states_level1(dev_state->states); + else + BUG_ON(dev_state->pasid_levels != 0); + + free_page((unsigned long)dev_state->states); +} + +static struct pasid_state *mn_to_state(struct mmu_notifier *mn) +{ + return container_of(mn, struct pasid_state, mn); +} + +static void mn_invalidate_range(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + struct pasid_state *pasid_state; + struct device_state *dev_state; + + pasid_state = mn_to_state(mn); + dev_state = pasid_state->device_state; + + if ((start ^ (end - 1)) < PAGE_SIZE) + amd_iommu_flush_page(dev_state->domain, pasid_state->pasid, + start); + else + amd_iommu_flush_tlb(dev_state->domain, pasid_state->pasid); +} + +static void mn_release(struct mmu_notifier *mn, struct mm_struct *mm) +{ + struct pasid_state *pasid_state; + struct device_state *dev_state; + bool run_inv_ctx_cb; + + might_sleep(); + + pasid_state = mn_to_state(mn); + dev_state = pasid_state->device_state; + run_inv_ctx_cb = !pasid_state->invalid; + + if (run_inv_ctx_cb && dev_state->inv_ctx_cb) + dev_state->inv_ctx_cb(dev_state->pdev, pasid_state->pasid); + + unbind_pasid(pasid_state); +} + +static const struct mmu_notifier_ops iommu_mn = { + .release = mn_release, + .invalidate_range = mn_invalidate_range, +}; + +static void set_pri_tag_status(struct pasid_state *pasid_state, + u16 tag, int status) +{ + unsigned long flags; + + spin_lock_irqsave(&pasid_state->lock, flags); + pasid_state->pri[tag].status = status; + spin_unlock_irqrestore(&pasid_state->lock, flags); +} + +static void finish_pri_tag(struct device_state *dev_state, + struct pasid_state *pasid_state, + u16 tag) +{ + unsigned long flags; + + spin_lock_irqsave(&pasid_state->lock, flags); + if (atomic_dec_and_test(&pasid_state->pri[tag].inflight) && + pasid_state->pri[tag].finish) { + amd_iommu_complete_ppr(dev_state->pdev, pasid_state->pasid, + pasid_state->pri[tag].status, tag); + pasid_state->pri[tag].finish = false; + pasid_state->pri[tag].status = PPR_SUCCESS; + } + spin_unlock_irqrestore(&pasid_state->lock, flags); +} + +static void handle_fault_error(struct fault *fault) +{ + int status; + + if (!fault->dev_state->inv_ppr_cb) { + set_pri_tag_status(fault->state, fault->tag, PPR_INVALID); + return; + } + + status = fault->dev_state->inv_ppr_cb(fault->dev_state->pdev, + fault->pasid, + fault->address, + fault->flags); + switch (status) { + case AMD_IOMMU_INV_PRI_RSP_SUCCESS: + set_pri_tag_status(fault->state, fault->tag, PPR_SUCCESS); + break; + case AMD_IOMMU_INV_PRI_RSP_INVALID: + set_pri_tag_status(fault->state, fault->tag, PPR_INVALID); + break; + case AMD_IOMMU_INV_PRI_RSP_FAIL: + set_pri_tag_status(fault->state, fault->tag, PPR_FAILURE); + break; + default: + BUG(); + } +} + +static bool access_error(struct vm_area_struct *vma, struct fault *fault) +{ + unsigned long requested = 0; + + if (fault->flags & PPR_FAULT_EXEC) + requested |= VM_EXEC; + + if (fault->flags & PPR_FAULT_READ) + requested |= VM_READ; + + if (fault->flags & PPR_FAULT_WRITE) + requested |= VM_WRITE; + + return (requested & ~vma->vm_flags) != 0; +} + +static void do_fault(struct work_struct *work) +{ + struct fault *fault = container_of(work, struct fault, work); + struct vm_area_struct *vma; + vm_fault_t ret = VM_FAULT_ERROR; + unsigned int flags = 0; + struct mm_struct *mm; + u64 address; + + mm = fault->state->mm; + address = fault->address; + + if (fault->flags & PPR_FAULT_USER) + flags |= FAULT_FLAG_USER; + if (fault->flags & PPR_FAULT_WRITE) + flags |= FAULT_FLAG_WRITE; + flags |= FAULT_FLAG_REMOTE; + + mmap_read_lock(mm); + vma = find_extend_vma(mm, address); + if (!vma || address < vma->vm_start) + /* failed to get a vma in the right range */ + goto out; + + /* Check if we have the right permissions on the vma */ + if (access_error(vma, fault)) + goto out; + + ret = handle_mm_fault(vma, address, flags); +out: + mmap_read_unlock(mm); + + if (ret & VM_FAULT_ERROR) + /* failed to service fault */ + handle_fault_error(fault); + + finish_pri_tag(fault->dev_state, fault->state, fault->tag); + + put_pasid_state(fault->state); + + kfree(fault); +} + +static int ppr_notifier(struct notifier_block *nb, unsigned long e, void *data) +{ + struct amd_iommu_fault *iommu_fault; + struct pasid_state *pasid_state; + struct device_state *dev_state; + struct pci_dev *pdev = NULL; + unsigned long flags; + struct fault *fault; + bool finish; + u16 tag, devid; + int ret; + + iommu_fault = data; + tag = iommu_fault->tag & 0x1ff; + finish = (iommu_fault->tag >> 9) & 1; + + devid = iommu_fault->device_id; + pdev = pci_get_domain_bus_and_slot(0, PCI_BUS_NUM(devid), + devid & 0xff); + if (!pdev) + return -ENODEV; + + ret = NOTIFY_DONE; + + /* In kdump kernel pci dev is not initialized yet -> send INVALID */ + if (amd_iommu_is_attach_deferred(NULL, &pdev->dev)) { + amd_iommu_complete_ppr(pdev, iommu_fault->pasid, + PPR_INVALID, tag); + goto out; + } + + dev_state = get_device_state(iommu_fault->device_id); + if (dev_state == NULL) + goto out; + + pasid_state = get_pasid_state(dev_state, iommu_fault->pasid); + if (pasid_state == NULL || pasid_state->invalid) { + /* We know the device but not the PASID -> send INVALID */ + amd_iommu_complete_ppr(dev_state->pdev, iommu_fault->pasid, + PPR_INVALID, tag); + goto out_drop_state; + } + + spin_lock_irqsave(&pasid_state->lock, flags); + atomic_inc(&pasid_state->pri[tag].inflight); + if (finish) + pasid_state->pri[tag].finish = true; + spin_unlock_irqrestore(&pasid_state->lock, flags); + + fault = kzalloc(sizeof(*fault), GFP_ATOMIC); + if (fault == NULL) { + /* We are OOM - send success and let the device re-fault */ + finish_pri_tag(dev_state, pasid_state, tag); + goto out_drop_state; + } + + fault->dev_state = dev_state; + fault->address = iommu_fault->address; + fault->state = pasid_state; + fault->tag = tag; + fault->finish = finish; + fault->pasid = iommu_fault->pasid; + fault->flags = iommu_fault->flags; + INIT_WORK(&fault->work, do_fault); + + queue_work(iommu_wq, &fault->work); + + ret = NOTIFY_OK; + +out_drop_state: + + if (ret != NOTIFY_OK && pasid_state) + put_pasid_state(pasid_state); + + put_device_state(dev_state); + +out: + return ret; +} + +static struct notifier_block ppr_nb = { + .notifier_call = ppr_notifier, +}; + +int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid, + struct task_struct *task) +{ + struct pasid_state *pasid_state; + struct device_state *dev_state; + struct mm_struct *mm; + u16 devid; + int ret; + + might_sleep(); + + if (!amd_iommu_v2_supported()) + return -ENODEV; + + devid = device_id(pdev); + dev_state = get_device_state(devid); + + if (dev_state == NULL) + return -EINVAL; + + ret = -EINVAL; + if (pasid < 0 || pasid >= dev_state->max_pasids) + goto out; + + ret = -ENOMEM; + pasid_state = kzalloc(sizeof(*pasid_state), GFP_KERNEL); + if (pasid_state == NULL) + goto out; + + + atomic_set(&pasid_state->count, 1); + init_waitqueue_head(&pasid_state->wq); + spin_lock_init(&pasid_state->lock); + + mm = get_task_mm(task); + pasid_state->mm = mm; + pasid_state->device_state = dev_state; + pasid_state->pasid = pasid; + pasid_state->invalid = true; /* Mark as valid only if we are + done with setting up the pasid */ + pasid_state->mn.ops = &iommu_mn; + + if (pasid_state->mm == NULL) + goto out_free; + + mmu_notifier_register(&pasid_state->mn, mm); + + ret = set_pasid_state(dev_state, pasid_state, pasid); + if (ret) + goto out_unregister; + + ret = amd_iommu_domain_set_gcr3(dev_state->domain, pasid, + __pa(pasid_state->mm->pgd)); + if (ret) + goto out_clear_state; + + /* Now we are ready to handle faults */ + pasid_state->invalid = false; + + /* + * Drop the reference to the mm_struct here. We rely on the + * mmu_notifier release call-back to inform us when the mm + * is going away. + */ + mmput(mm); + + return 0; + +out_clear_state: + clear_pasid_state(dev_state, pasid); + +out_unregister: + mmu_notifier_unregister(&pasid_state->mn, mm); + mmput(mm); + +out_free: + free_pasid_state(pasid_state); + +out: + put_device_state(dev_state); + + return ret; +} +EXPORT_SYMBOL(amd_iommu_bind_pasid); + +void amd_iommu_unbind_pasid(struct pci_dev *pdev, int pasid) +{ + struct pasid_state *pasid_state; + struct device_state *dev_state; + u16 devid; + + might_sleep(); + + if (!amd_iommu_v2_supported()) + return; + + devid = device_id(pdev); + dev_state = get_device_state(devid); + if (dev_state == NULL) + return; + + if (pasid < 0 || pasid >= dev_state->max_pasids) + goto out; + + pasid_state = get_pasid_state(dev_state, pasid); + if (pasid_state == NULL) + goto out; + /* + * Drop reference taken here. We are safe because we still hold + * the reference taken in the amd_iommu_bind_pasid function. + */ + put_pasid_state(pasid_state); + + /* Clear the pasid state so that the pasid can be re-used */ + clear_pasid_state(dev_state, pasid_state->pasid); + + /* + * Call mmu_notifier_unregister to drop our reference + * to pasid_state->mm + */ + mmu_notifier_unregister(&pasid_state->mn, pasid_state->mm); + + put_pasid_state_wait(pasid_state); /* Reference taken in + amd_iommu_bind_pasid */ +out: + /* Drop reference taken in this function */ + put_device_state(dev_state); + + /* Drop reference taken in amd_iommu_bind_pasid */ + put_device_state(dev_state); +} +EXPORT_SYMBOL(amd_iommu_unbind_pasid); + +int amd_iommu_init_device(struct pci_dev *pdev, int pasids) +{ + struct device_state *dev_state; + struct iommu_group *group; + unsigned long flags; + int ret, tmp; + u16 devid; + + might_sleep(); + + if (!amd_iommu_v2_supported()) + return -ENODEV; + + if (pasids <= 0 || pasids > (PASID_MASK + 1)) + return -EINVAL; + + devid = device_id(pdev); + + dev_state = kzalloc(sizeof(*dev_state), GFP_KERNEL); + if (dev_state == NULL) + return -ENOMEM; + + spin_lock_init(&dev_state->lock); + init_waitqueue_head(&dev_state->wq); + dev_state->pdev = pdev; + dev_state->devid = devid; + + tmp = pasids; + for (dev_state->pasid_levels = 0; (tmp - 1) & ~0x1ff; tmp >>= 9) + dev_state->pasid_levels += 1; + + atomic_set(&dev_state->count, 1); + dev_state->max_pasids = pasids; + + ret = -ENOMEM; + dev_state->states = (void *)get_zeroed_page(GFP_KERNEL); + if (dev_state->states == NULL) + goto out_free_dev_state; + + dev_state->domain = iommu_domain_alloc(&pci_bus_type); + if (dev_state->domain == NULL) + goto out_free_states; + + amd_iommu_domain_direct_map(dev_state->domain); + + ret = amd_iommu_domain_enable_v2(dev_state->domain, pasids); + if (ret) + goto out_free_domain; + + group = iommu_group_get(&pdev->dev); + if (!group) { + ret = -EINVAL; + goto out_free_domain; + } + + ret = iommu_attach_group(dev_state->domain, group); + if (ret != 0) + goto out_drop_group; + + iommu_group_put(group); + + spin_lock_irqsave(&state_lock, flags); + + if (__get_device_state(devid) != NULL) { + spin_unlock_irqrestore(&state_lock, flags); + ret = -EBUSY; + goto out_free_domain; + } + + list_add_tail(&dev_state->list, &state_list); + + spin_unlock_irqrestore(&state_lock, flags); + + return 0; + +out_drop_group: + iommu_group_put(group); + +out_free_domain: + iommu_domain_free(dev_state->domain); + +out_free_states: + free_page((unsigned long)dev_state->states); + +out_free_dev_state: + kfree(dev_state); + + return ret; +} +EXPORT_SYMBOL(amd_iommu_init_device); + +void amd_iommu_free_device(struct pci_dev *pdev) +{ + struct device_state *dev_state; + unsigned long flags; + u16 devid; + + if (!amd_iommu_v2_supported()) + return; + + devid = device_id(pdev); + + spin_lock_irqsave(&state_lock, flags); + + dev_state = __get_device_state(devid); + if (dev_state == NULL) { + spin_unlock_irqrestore(&state_lock, flags); + return; + } + + list_del(&dev_state->list); + + spin_unlock_irqrestore(&state_lock, flags); + + /* Get rid of any remaining pasid states */ + free_pasid_states(dev_state); + + put_device_state(dev_state); + /* + * Wait until the last reference is dropped before freeing + * the device state. + */ + wait_event(dev_state->wq, !atomic_read(&dev_state->count)); + free_device_state(dev_state); +} +EXPORT_SYMBOL(amd_iommu_free_device); + +int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev, + amd_iommu_invalid_ppr_cb cb) +{ + struct device_state *dev_state; + unsigned long flags; + u16 devid; + int ret; + + if (!amd_iommu_v2_supported()) + return -ENODEV; + + devid = device_id(pdev); + + spin_lock_irqsave(&state_lock, flags); + + ret = -EINVAL; + dev_state = __get_device_state(devid); + if (dev_state == NULL) + goto out_unlock; + + dev_state->inv_ppr_cb = cb; + + ret = 0; + +out_unlock: + spin_unlock_irqrestore(&state_lock, flags); + + return ret; +} +EXPORT_SYMBOL(amd_iommu_set_invalid_ppr_cb); + +int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev, + amd_iommu_invalidate_ctx cb) +{ + struct device_state *dev_state; + unsigned long flags; + u16 devid; + int ret; + + if (!amd_iommu_v2_supported()) + return -ENODEV; + + devid = device_id(pdev); + + spin_lock_irqsave(&state_lock, flags); + + ret = -EINVAL; + dev_state = __get_device_state(devid); + if (dev_state == NULL) + goto out_unlock; + + dev_state->inv_ctx_cb = cb; + + ret = 0; + +out_unlock: + spin_unlock_irqrestore(&state_lock, flags); + + return ret; +} +EXPORT_SYMBOL(amd_iommu_set_invalidate_ctx_cb); + +static int __init amd_iommu_v2_init(void) +{ + int ret; + + pr_info("AMD IOMMUv2 driver by Joerg Roedel <jroedel@suse.de>\n"); + + if (!amd_iommu_v2_supported()) { + pr_info("AMD IOMMUv2 functionality not available on this system\n"); + /* + * Load anyway to provide the symbols to other modules + * which may use AMD IOMMUv2 optionally. + */ + return 0; + } + + spin_lock_init(&state_lock); + + ret = -ENOMEM; + iommu_wq = alloc_workqueue("amd_iommu_v2", WQ_MEM_RECLAIM, 0); + if (iommu_wq == NULL) + goto out; + + amd_iommu_register_ppr_notifier(&ppr_nb); + + return 0; + +out: + return ret; +} + +static void __exit amd_iommu_v2_exit(void) +{ + struct device_state *dev_state; + int i; + + if (!amd_iommu_v2_supported()) + return; + + amd_iommu_unregister_ppr_notifier(&ppr_nb); + + flush_workqueue(iommu_wq); + + /* + * The loop below might call flush_workqueue(), so call + * destroy_workqueue() after it + */ + for (i = 0; i < MAX_DEVICES; ++i) { + dev_state = get_device_state(i); + + if (dev_state == NULL) + continue; + + WARN_ON_ONCE(1); + + put_device_state(dev_state); + amd_iommu_free_device(dev_state->pdev); + } + + destroy_workqueue(iommu_wq); +} + +module_init(amd_iommu_v2_init); +module_exit(amd_iommu_v2_exit); |