iommu/amd: Implement device aquisition code for IOMMUv2
This patch adds the amd_iommu_init_device() and
amd_iommu_free_device() functions which make a device and
the IOMMU ready for IOMMUv2 usage.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index a19e07d..bfceed2 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -16,20 +16,230 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+#include <linux/amd-iommu.h>
+#include <linux/mm_types.h>
#include <linux/module.h>
+#include <linux/iommu.h>
+#include <linux/pci.h>
+#include <linux/gfp.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;
+};
+
+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 pri_queue pri[PRI_QUEUE_SIZE]; /* PRI tag states */
+ struct device_state *device_state; /* Link to our device_state */
+ int pasid; /* PASID index */
+};
+
+struct device_state {
+ atomic_t count;
+ struct pci_dev *pdev;
+ struct pasid_state **states;
+ struct iommu_domain *domain;
+ int pasid_levels;
+ int max_pasids;
+ spinlock_t lock;
+};
+
+struct device_state **state_table;
+static spinlock_t state_lock;
+
+/* List and lock for all pasid_states */
+static LIST_HEAD(pasid_state_list);
+
+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)
+{
+ iommu_detach_device(dev_state->domain, &dev_state->pdev->dev);
+ iommu_domain_free(dev_state->domain);
+ kfree(dev_state);
+}
+
+static void put_device_state(struct device_state *dev_state)
+{
+ if (atomic_dec_and_test(&dev_state->count))
+ free_device_state(dev_state);
+}
+
+int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
+{
+ struct device_state *dev_state;
+ 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);
+ dev_state->pdev = pdev;
+
+ 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;
+
+ ret = iommu_attach_device(dev_state->domain, &pdev->dev);
+ if (ret != 0)
+ goto out_free_domain;
+
+ spin_lock_irqsave(&state_lock, flags);
+
+ if (state_table[devid] != NULL) {
+ spin_unlock_irqrestore(&state_lock, flags);
+ ret = -EBUSY;
+ goto out_free_domain;
+ }
+
+ state_table[devid] = dev_state;
+
+ spin_unlock_irqrestore(&state_lock, flags);
+
+ return 0;
+
+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 = state_table[devid];
+ if (dev_state == NULL) {
+ spin_unlock_irqrestore(&state_lock, flags);
+ return;
+ }
+
+ state_table[devid] = NULL;
+
+ spin_unlock_irqrestore(&state_lock, flags);
+
+ put_device_state(dev_state);
+}
+EXPORT_SYMBOL(amd_iommu_free_device);
+
static int __init amd_iommu_v2_init(void)
{
+ size_t state_table_size;
+
pr_info("AMD IOMMUv2 driver by Joerg Roedel <joerg.roedel@amd.com>");
+ spin_lock_init(&state_lock);
+
+ state_table_size = MAX_DEVICES * sizeof(struct device_state *);
+ state_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(state_table_size));
+ if (state_table == NULL)
+ return -ENOMEM;
+
return 0;
}
static void __exit amd_iommu_v2_exit(void)
{
+ struct device_state *dev_state;
+ size_t state_table_size;
+ int i;
+
+ for (i = 0; i < MAX_DEVICES; ++i) {
+ dev_state = get_device_state(i);
+
+ if (dev_state == NULL)
+ continue;
+
+ WARN_ON_ONCE(1);
+
+ amd_iommu_free_device(dev_state->pdev);
+ put_device_state(dev_state);
+ }
+
+ state_table_size = MAX_DEVICES * sizeof(struct device_state *);
+ free_pages((unsigned long)state_table, get_order(state_table_size));
}
module_init(amd_iommu_v2_init);
diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h
index 4152c30..e8c7a2e 100644
--- a/include/linux/amd-iommu.h
+++ b/include/linux/amd-iommu.h
@@ -20,10 +20,12 @@
#ifndef _ASM_X86_AMD_IOMMU_H
#define _ASM_X86_AMD_IOMMU_H
-#include <linux/irqreturn.h>
+#include <linux/types.h>
#ifdef CONFIG_AMD_IOMMU
+struct pci_dev;
+
extern int amd_iommu_detect(void);
@@ -33,6 +35,7 @@
* @pdev: The PCI device the workaround is necessary for
* @erratum: The erratum workaround to enable
*
+ * The function needs to be called before amd_iommu_init_device().
* Possible values for the erratum number are for now:
* - AMD_PRI_DEV_ERRATUM_ENABLE_RESET - Reset PRI capability when PRI
* is enabled
@@ -44,6 +47,24 @@
extern void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum);
+/**
+ * amd_iommu_init_device() - Init device for use with IOMMUv2 driver
+ * @pdev: The PCI device to initialize
+ * @pasids: Number of PASIDs to support for this device
+ *
+ * This function does all setup for the device pdev so that it can be
+ * used with IOMMUv2.
+ * Returns 0 on success or negative value on error.
+ */
+extern int amd_iommu_init_device(struct pci_dev *pdev, int pasids);
+
+/**
+ * amd_iommu_free_device() - Free all IOMMUv2 related device resources
+ * and disable IOMMUv2 usage for this device
+ * @pdev: The PCI device to disable IOMMUv2 usage for'
+ */
+extern void amd_iommu_free_device(struct pci_dev *pdev);
+
#else
static inline int amd_iommu_detect(void) { return -ENODEV; }