[PATCH v6 07/22] vfio: VFIO_IOMMU_ATTACH/DETACH_PASID_TABLE

From: Eric Auger <eric.auger@redhat.com>
To: eric.auger.pro@gmail.com, eric.auger@redhat.com,
	iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu,
	joro@8bytes.org, alex.williamson@redhat.com,
	jacob.jun.pan@linux.intel.com, yi.l.liu@linux.intel.com,
	jean-philippe.brucker@arm.com, will.deacon@arm.com,
	robin.murphy@arm.com
Cc: kevin.tian@intel.com, ashok.raj@intel.com, marc.zyngier@arm.com,
	christoffer.dall@arm.com, peter.maydell@linaro.org,
	vincent.stehle@arm.com
Subject: [PATCH v6 07/22] vfio: VFIO_IOMMU_ATTACH/DETACH_PASID_TABLE
Date: Sun, 17 Mar 2019 18:22:17 +0100	[thread overview]
Message-ID: <20190317172232.1068-8-eric.auger@redhat.com> (raw)
In-Reply-To: <20190317172232.1068-1-eric.auger@redhat.com>

From: "Liu, Yi L" <yi.l.liu@linux.intel.com>

This patch adds VFIO_IOMMU_ATTACH/DETACH_PASID_TABLE ioctl
which aims to pass/withdraw the virtual iommu guest configuration
to/from the VFIO driver downto to the iommu subsystem.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Liu, Yi L <yi.l.liu@linux.intel.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>

---
v3 -> v4:
- restore ATTACH/DETACH
- add unwind on failure

v2 -> v3:
- s/BIND_PASID_TABLE/SET_PASID_TABLE

v1 -> v2:
- s/BIND_GUEST_STAGE/BIND_PASID_TABLE
- remove the struct device arg
---
 drivers/vfio/vfio_iommu_type1.c | 53 +++++++++++++++++++++++++++++++++
 include/uapi/linux/vfio.h       | 17 +++++++++++
 2 files changed, 70 insertions(+)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 73652e21efec..222e9199edbf 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -1644,6 +1644,43 @@ static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu)
 	return ret;
 }
 
+static void
+vfio_detach_pasid_table(struct vfio_iommu *iommu)
+{
+	struct vfio_domain *d;
+
+	mutex_lock(&iommu->lock);
+
+	list_for_each_entry(d, &iommu->domain_list, next) {
+		iommu_detach_pasid_table(d->domain);
+	}
+	mutex_unlock(&iommu->lock);
+}
+
+static int
+vfio_attach_pasid_table(struct vfio_iommu *iommu,
+			struct vfio_iommu_type1_attach_pasid_table *ustruct)
+{
+	struct vfio_domain *d;
+	int ret = 0;
+
+	mutex_lock(&iommu->lock);
+
+	list_for_each_entry(d, &iommu->domain_list, next) {
+		ret = iommu_attach_pasid_table(d->domain, &ustruct->config);
+		if (ret)
+			goto unwind;
+	}
+	goto unlock;
+unwind:
+	list_for_each_entry_continue_reverse(d, &iommu->domain_list, next) {
+		iommu_detach_pasid_table(d->domain);
+	}
+unlock:
+	mutex_unlock(&iommu->lock);
+	return ret;
+}
+
 static long vfio_iommu_type1_ioctl(void *iommu_data,
 				   unsigned int cmd, unsigned long arg)
 {
@@ -1714,6 +1751,22 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
 
 		return copy_to_user((void __user *)arg, &unmap, minsz) ?
 			-EFAULT : 0;
+	} else if (cmd == VFIO_IOMMU_ATTACH_PASID_TABLE) {
+		struct vfio_iommu_type1_attach_pasid_table ustruct;
+
+		minsz = offsetofend(struct vfio_iommu_type1_attach_pasid_table,
+				    config);
+
+		if (copy_from_user(&ustruct, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (ustruct.argsz < minsz || ustruct.flags)
+			return -EINVAL;
+
+		return vfio_attach_pasid_table(iommu, &ustruct);
+	} else if (cmd == VFIO_IOMMU_DETACH_PASID_TABLE) {
+		vfio_detach_pasid_table(iommu);
+		return 0;
 	}
 
 	return -ENOTTY;
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 02bb7ad6e986..329d378565d9 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -14,6 +14,7 @@
 
 #include <linux/types.h>
 #include <linux/ioctl.h>
+#include <linux/iommu.h>
 
 #define VFIO_API_VERSION	0
 
@@ -759,6 +760,22 @@ struct vfio_iommu_type1_dma_unmap {
 #define VFIO_IOMMU_ENABLE	_IO(VFIO_TYPE, VFIO_BASE + 15)
 #define VFIO_IOMMU_DISABLE	_IO(VFIO_TYPE, VFIO_BASE + 16)
 
+/**
+ * VFIO_IOMMU_ATTACH_PASID_TABLE - _IOWR(VFIO_TYPE, VFIO_BASE + 22,
+ *			struct vfio_iommu_type1_attach_pasid_table)
+ *
+ * Passes the PASID table to the host. Calling ATTACH_PASID_TABLE
+ * while a table is already installed is allowed: it replaces the old
+ * table. DETACH does a comprehensive tear down of the nested mode.
+ */
+struct vfio_iommu_type1_attach_pasid_table {
+	__u32	argsz;
+	__u32	flags;
+	struct iommu_pasid_table_config config;
+};
+#define VFIO_IOMMU_ATTACH_PASID_TABLE	_IO(VFIO_TYPE, VFIO_BASE + 22)
+#define VFIO_IOMMU_DETACH_PASID_TABLE	_IO(VFIO_TYPE, VFIO_BASE + 23)
+
 /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */
 
 /*
-- 
2.20.1

