diff options
Diffstat (limited to 'drivers/iommu/intel/iommu.c')
-rw-r--r-- | drivers/iommu/intel/iommu.c | 88 |
1 files changed, 86 insertions, 2 deletions
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index fc52fcd786aa..025d7385cf58 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -97,6 +97,81 @@ static phys_addr_t root_entry_uctp(struct root_entry *re) return re->hi & VTD_PAGE_MASK; } +static int device_rid_cmp_key(const void *key, const struct rb_node *node) +{ + struct device_domain_info *info = + rb_entry(node, struct device_domain_info, node); + const u16 *rid_lhs = key; + + if (*rid_lhs < PCI_DEVID(info->bus, info->devfn)) + return -1; + + if (*rid_lhs > PCI_DEVID(info->bus, info->devfn)) + return 1; + + return 0; +} + +static int device_rid_cmp(struct rb_node *lhs, const struct rb_node *rhs) +{ + struct device_domain_info *info = + rb_entry(lhs, struct device_domain_info, node); + u16 key = PCI_DEVID(info->bus, info->devfn); + + return device_rid_cmp_key(&key, rhs); +} + +/* + * Looks up an IOMMU-probed device using its source ID. + * + * Returns the pointer to the device if there is a match. Otherwise, + * returns NULL. + * + * Note that this helper doesn't guarantee that the device won't be + * released by the iommu subsystem after being returned. The caller + * should use its own synchronization mechanism to avoid the device + * being released during its use if its possibly the case. + */ +struct device *device_rbtree_find(struct intel_iommu *iommu, u16 rid) +{ + struct device_domain_info *info = NULL; + struct rb_node *node; + unsigned long flags; + + spin_lock_irqsave(&iommu->device_rbtree_lock, flags); + node = rb_find(&rid, &iommu->device_rbtree, device_rid_cmp_key); + if (node) + info = rb_entry(node, struct device_domain_info, node); + spin_unlock_irqrestore(&iommu->device_rbtree_lock, flags); + + return info ? info->dev : NULL; +} + +static int device_rbtree_insert(struct intel_iommu *iommu, + struct device_domain_info *info) +{ + struct rb_node *curr; + unsigned long flags; + + spin_lock_irqsave(&iommu->device_rbtree_lock, flags); + curr = rb_find_add(&info->node, &iommu->device_rbtree, device_rid_cmp); + spin_unlock_irqrestore(&iommu->device_rbtree_lock, flags); + if (WARN_ON(curr)) + return -EEXIST; + + return 0; +} + +static void device_rbtree_remove(struct device_domain_info *info) +{ + struct intel_iommu *iommu = info->iommu; + unsigned long flags; + + spin_lock_irqsave(&iommu->device_rbtree_lock, flags); + rb_erase(&info->node, &iommu->device_rbtree); + spin_unlock_irqrestore(&iommu->device_rbtree_lock, flags); +} + /* * This domain is a statically identity mapping domain. * 1. This domain creats a static 1:1 mapping to all usable memory. @@ -4261,25 +4336,34 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev) } dev_iommu_priv_set(dev, info); + ret = device_rbtree_insert(iommu, info); + if (ret) + goto free; if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev)) { ret = intel_pasid_alloc_table(dev); if (ret) { dev_err(dev, "PASID table allocation failed\n"); - kfree(info); - return ERR_PTR(ret); + goto clear_rbtree; } } intel_iommu_debugfs_create_dev(info); return &iommu->iommu; +clear_rbtree: + device_rbtree_remove(info); +free: + kfree(info); + + return ERR_PTR(ret); } static void intel_iommu_release_device(struct device *dev) { struct device_domain_info *info = dev_iommu_priv_get(dev); + device_rbtree_remove(info); dmar_remove_one_dev_info(dev); intel_pasid_free_table(dev); intel_iommu_debugfs_remove_dev(info); |