x86, AMD IOMMU: add functions to find IOMMU device resources
This patch adds functions necessary to find the IOMMU resources for a specific
device.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: Sebastian.Biemueller@amd.com
Cc: robert.richter@amd.com
Cc: joro@8bytes.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index c43d15d..47e80b5 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -461,3 +461,78 @@
return NULL;
}
+static struct protection_domain *domain_for_device(u16 devid)
+{
+ struct protection_domain *dom;
+ unsigned long flags;
+
+ read_lock_irqsave(&amd_iommu_devtable_lock, flags);
+ dom = amd_iommu_pd_table[devid];
+ read_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
+
+ return dom;
+}
+
+static void set_device_domain(struct amd_iommu *iommu,
+ struct protection_domain *domain,
+ u16 devid)
+{
+ unsigned long flags;
+
+ u64 pte_root = virt_to_phys(domain->pt_root);
+
+ pte_root |= (domain->mode & 0x07) << 9;
+ pte_root |= IOMMU_PTE_IR | IOMMU_PTE_IW | IOMMU_PTE_P | 2;
+
+ write_lock_irqsave(&amd_iommu_devtable_lock, flags);
+ amd_iommu_dev_table[devid].data[0] = pte_root;
+ amd_iommu_dev_table[devid].data[1] = pte_root >> 32;
+ amd_iommu_dev_table[devid].data[2] = domain->id;
+
+ amd_iommu_pd_table[devid] = domain;
+ write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
+
+ iommu_queue_inv_dev_entry(iommu, devid);
+
+ iommu->need_sync = 1;
+}
+
+static int get_device_resources(struct device *dev,
+ struct amd_iommu **iommu,
+ struct protection_domain **domain,
+ u16 *bdf)
+{
+ struct dma_ops_domain *dma_dom;
+ struct pci_dev *pcidev;
+ u16 _bdf;
+
+ BUG_ON(!dev || dev->bus != &pci_bus_type || !dev->dma_mask);
+
+ pcidev = to_pci_dev(dev);
+ _bdf = (pcidev->bus->number << 8) | pcidev->devfn;
+
+ if (_bdf >= amd_iommu_last_bdf) {
+ *iommu = NULL;
+ *domain = NULL;
+ *bdf = 0xffff;
+ return 0;
+ }
+
+ *bdf = amd_iommu_alias_table[_bdf];
+
+ *iommu = amd_iommu_rlookup_table[*bdf];
+ if (*iommu == NULL)
+ return 0;
+ dma_dom = (*iommu)->default_dom;
+ *domain = domain_for_device(*bdf);
+ if (*domain == NULL) {
+ *domain = &dma_dom->domain;
+ set_device_domain(*iommu, *domain, *bdf);
+ printk(KERN_INFO "AMD IOMMU: Using protection domain %d for "
+ "device ", (*domain)->id);
+ print_devid(_bdf, 1);
+ }
+
+ return 1;
+}
+