iommu/virtio: Update to most recent specification

Following specification review a few things were changed in v8 of the
virtio-iommu series [1], but have been omitted when merging the base
driver. Add them now:

* Remove the EXEC flag.
* Add feature bit for the MMIO flag.
* Change domain_bits to domain_range.
* Add NOMEM status flag.

[1] https://lore.kernel.org/linux-iommu/20190530170929.19366-1-jean-philippe.brucker@arm.com/

Fixes: edcd69ab9a32 ("iommu: Add virtio-iommu driver")
Reported-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 433f4d2..80a740d 100644 (file)
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -2,7 +2,7 @@
 /*
  * Virtio driver for the paravirtualized IOMMU
  *
- * Copyright (C) 2018 Arm Limited
+ * Copyright (C) 2019 Arm Limited
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -47,7 +47,10 @@ struct viommu_dev {
        /* Device configuration */
        struct iommu_domain_geometry    geometry;
        u64                             pgsize_bitmap;
-       u8                              domain_bits;
+       u32                             first_domain;
+       u32                             last_domain;
+       /* Supported MAP flags */
+       u32                             map_flags;
        u32                             probe_size;
 };
 
@@ -62,6 +65,7 @@ struct viommu_domain {
        struct viommu_dev               *viommu;
        struct mutex                    mutex; /* protects viommu pointer */
        unsigned int                    id;
+       u32                             map_flags;
 
        spinlock_t                      mappings_lock;
        struct rb_root_cached           mappings;
@@ -113,6 +117,8 @@ static int viommu_get_req_errno(void *buf, size_t len)
                return -ENOENT;
        case VIRTIO_IOMMU_S_FAULT:
                return -EFAULT;
+       case VIRTIO_IOMMU_S_NOMEM:
+               return -ENOMEM;
        case VIRTIO_IOMMU_S_IOERR:
        case VIRTIO_IOMMU_S_DEVERR:
        default:
@@ -607,15 +613,15 @@ static int viommu_domain_finalise(struct viommu_dev *viommu,
 {
        int ret;
        struct viommu_domain *vdomain = to_viommu_domain(domain);
-       unsigned int max_domain = viommu->domain_bits > 31 ? ~0 :
-                                 (1U << viommu->domain_bits) - 1;
 
        vdomain->viommu         = viommu;
+       vdomain->map_flags      = viommu->map_flags;
 
        domain->pgsize_bitmap   = viommu->pgsize_bitmap;
        domain->geometry        = viommu->geometry;
 
-       ret = ida_alloc_max(&viommu->domain_ids, max_domain, GFP_KERNEL);
+       ret = ida_alloc_range(&viommu->domain_ids, viommu->first_domain,
+                             viommu->last_domain, GFP_KERNEL);
        if (ret >= 0)
                vdomain->id = (unsigned int)ret;
 
@@ -710,7 +716,7 @@ static int viommu_map(struct iommu_domain *domain, unsigned long iova,
                      phys_addr_t paddr, size_t size, int prot)
 {
        int ret;
-       int flags;
+       u32 flags;
        struct virtio_iommu_req_map map;
        struct viommu_domain *vdomain = to_viommu_domain(domain);
 
@@ -718,6 +724,9 @@ static int viommu_map(struct iommu_domain *domain, unsigned long iova,
                (prot & IOMMU_WRITE ? VIRTIO_IOMMU_MAP_F_WRITE : 0) |
                (prot & IOMMU_MMIO ? VIRTIO_IOMMU_MAP_F_MMIO : 0);
 
+       if (flags & ~vdomain->map_flags)
+               return -EINVAL;
+
        ret = viommu_add_mapping(vdomain, iova, paddr, size, flags);
        if (ret)
                return ret;
@@ -1027,7 +1036,8 @@ static int viommu_probe(struct virtio_device *vdev)
                goto err_free_vqs;
        }
 
-       viommu->domain_bits = 32;
+       viommu->map_flags = VIRTIO_IOMMU_MAP_F_READ | VIRTIO_IOMMU_MAP_F_WRITE;
+       viommu->last_domain = ~0U;
 
        /* Optional features */
        virtio_cread_feature(vdev, VIRTIO_IOMMU_F_INPUT_RANGE,
@@ -1038,9 +1048,13 @@ static int viommu_probe(struct virtio_device *vdev)
                             struct virtio_iommu_config, input_range.end,
                             &input_end);
 
-       virtio_cread_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_BITS,
-                            struct virtio_iommu_config, domain_bits,
-                            &viommu->domain_bits);
+       virtio_cread_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_RANGE,
+                            struct virtio_iommu_config, domain_range.start,
+                            &viommu->first_domain);
+
+       virtio_cread_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_RANGE,
+                            struct virtio_iommu_config, domain_range.end,
+                            &viommu->last_domain);
 
        virtio_cread_feature(vdev, VIRTIO_IOMMU_F_PROBE,
                             struct virtio_iommu_config, probe_size,
@@ -1052,6 +1066,9 @@ static int viommu_probe(struct virtio_device *vdev)
                .force_aperture = true,
        };
 
+       if (virtio_has_feature(vdev, VIRTIO_IOMMU_F_MMIO))
+               viommu->map_flags |= VIRTIO_IOMMU_MAP_F_MMIO;
+
        viommu_ops.pgsize_bitmap = viommu->pgsize_bitmap;
 
        virtio_device_ready(vdev);
@@ -1130,9 +1147,10 @@ static void viommu_config_changed(struct virtio_device *vdev)
 
 static unsigned int features[] = {
        VIRTIO_IOMMU_F_MAP_UNMAP,
-       VIRTIO_IOMMU_F_DOMAIN_BITS,
        VIRTIO_IOMMU_F_INPUT_RANGE,
+       VIRTIO_IOMMU_F_DOMAIN_RANGE,
        VIRTIO_IOMMU_F_PROBE,
+       VIRTIO_IOMMU_F_MMIO,
 };
 
 static struct virtio_device_id id_table[] = {

diff --git a/include/uapi/linux/virtio_iommu.h b/include/uapi/linux/virtio_iommu.h
index ba1b460..237e36a 100644 (file)
--- a/include/uapi/linux/virtio_iommu.h
+++ b/include/uapi/linux/virtio_iommu.h
@@ -1,8 +1,8 @@
 /* SPDX-License-Identifier: BSD-3-Clause */
 /*
- * Virtio-iommu definition v0.9
+ * Virtio-iommu definition v0.12
  *
- * Copyright (C) 2018 Arm Ltd.
+ * Copyright (C) 2019 Arm Ltd.
  */
 #ifndef _UAPI_LINUX_VIRTIO_IOMMU_H
 #define _UAPI_LINUX_VIRTIO_IOMMU_H
@@ -11,26 +11,31 @@
 
 /* Feature bits */
 #define VIRTIO_IOMMU_F_INPUT_RANGE             0
-#define VIRTIO_IOMMU_F_DOMAIN_BITS             1
+#define VIRTIO_IOMMU_F_DOMAIN_RANGE            1
 #define VIRTIO_IOMMU_F_MAP_UNMAP               2
 #define VIRTIO_IOMMU_F_BYPASS                  3
 #define VIRTIO_IOMMU_F_PROBE                   4
+#define VIRTIO_IOMMU_F_MMIO                    5
 
-struct virtio_iommu_range {
-       __u64                                   start;
-       __u64                                   end;
+struct virtio_iommu_range_64 {
+       __le64                                  start;
+       __le64                                  end;
+};
+
+struct virtio_iommu_range_32 {
+       __le32                                  start;
+       __le32                                  end;
 };
 
 struct virtio_iommu_config {
        /* Supported page sizes */
-       __u64                                   page_size_mask;
+       __le64                                  page_size_mask;
        /* Supported IOVA range */
-       struct virtio_iommu_range               input_range;
+       struct virtio_iommu_range_64            input_range;
        /* Max domain ID size */
-       __u8                                    domain_bits;
-       __u8                                    padding[3];
+       struct virtio_iommu_range_32            domain_range;
        /* Probe buffer size */
-       __u32                                   probe_size;
+       __le32                                  probe_size;
 };
 
 /* Request types */
@@ -49,6 +54,7 @@ struct virtio_iommu_config {
 #define VIRTIO_IOMMU_S_RANGE                   0x05
 #define VIRTIO_IOMMU_S_NOENT                   0x06
 #define VIRTIO_IOMMU_S_FAULT                   0x07
+#define VIRTIO_IOMMU_S_NOMEM                   0x08
 
 struct virtio_iommu_req_head {
        __u8                                    type;
@@ -78,12 +84,10 @@ struct virtio_iommu_req_detach {
 
 #define VIRTIO_IOMMU_MAP_F_READ                        (1 << 0)
 #define VIRTIO_IOMMU_MAP_F_WRITE               (1 << 1)
-#define VIRTIO_IOMMU_MAP_F_EXEC                        (1 << 2)
-#define VIRTIO_IOMMU_MAP_F_MMIO                        (1 << 3)
+#define VIRTIO_IOMMU_MAP_F_MMIO                        (1 << 2)
 
 #define VIRTIO_IOMMU_MAP_F_MASK                        (VIRTIO_IOMMU_MAP_F_READ |      \
                                                 VIRTIO_IOMMU_MAP_F_WRITE |     \
-                                                VIRTIO_IOMMU_MAP_F_EXEC |      \
                                                 VIRTIO_IOMMU_MAP_F_MMIO)
 
 struct virtio_iommu_req_map {