diff options
Diffstat (limited to 'drivers/iommu/intel-pasid.c')
| -rw-r--r-- | drivers/iommu/intel-pasid.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c new file mode 100644 index 000000000000..fe95c9bd4d33 --- /dev/null +++ b/drivers/iommu/intel-pasid.c @@ -0,0 +1,239 @@ +// 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); +} |