From 562831747f6299abd481b5b00bd4fa19d5c8a259 Mon Sep 17 00:00:00 2001
From: Lu Baolu <baolu.lu@linux.intel.com>
Date: Sat, 14 Jul 2018 15:46:54 +0800
Subject: iommu/vt-d: Global PASID name space

This adds the system wide PASID name space for the PASID
allocation. Currently we are using per IOMMU PASID name
spaces which are not suitable for some use cases. For an
example, one application (associated with a PASID) might
talk to two physical devices simultaneously while the two
devices could reside behind two different IOMMU units.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/intel-pasid.c | 60 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 drivers/iommu/intel-pasid.c

(limited to 'drivers/iommu/intel-pasid.c')

diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c
new file mode 100644
index 000000000000..e918fe01ce7f
--- /dev/null
+++ b/drivers/iommu/intel-pasid.c
@@ -0,0 +1,60 @@
+// 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/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;
+}
-- 
cgit