[PATCH v7 07/23] vfio: VFIO_IOMMU_ATTACH/DETACH_PASID_TABLE

Eric Auger
2019-04-08T12:20:23Z

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>

---
v6 -> v7:
- add a comment related to VFIO_IOMMU_DETACH_PASID_TABLE

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 | 22 ++++++++++++++
2 files changed, 75 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..06db3247702f 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 +760,27 @@ 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)
+
+/**
+ * VFIO_IOMMU_DETACH_PASID_TABLE - - _IOWR(VFIO_TYPE, VFIO_BASE + 23)
+ * Detaches the PASID table
+ */
+#define VFIO_IOMMU_DETACH_PASID_TABLE _IO(VFIO_TYPE, VFIO_BASE + 23)
+
/* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */

/*