5 files changed, 204 insertions, 23 deletions

diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
index c84333eb5eb5..9de5ed38da83 100644
--- a/drivers/vfio/Kconfig
+++ b/drivers/vfio/Kconfig
@@ -21,7 +21,7 @@ config VFIO_VIRQFD
 menuconfig VFIO
         tristate "VFIO Non-Privileged userspace driver framework"
         depends on IOMMU_API
-        select VFIO_IOMMU_TYPE1 if (X86 || S390 || ARM_SMMU || ARM_SMMU_V3)
+        select VFIO_IOMMU_TYPE1 if (X86 || S390 || ARM || ARM64)
         select ANON_INODES
         help
           VFIO provides a framework for secure userspace device drivers.
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index cddb453a1ba5..50cdedfca9fe 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -434,10 +434,14 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
 {
         if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
                 u8 pin;
+
+                if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) ||
+                    vdev->nointx || vdev->pdev->is_virtfn)
+                        return 0;
+
                 pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
-                if (IS_ENABLED(CONFIG_VFIO_PCI_INTX) && !vdev->nointx && pin)
-                        return 1;
 
+                return pin ? 1 : 0;
         } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
                 u8 pos;
                 u16 flags;
diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index 115a36f6f403..423ea1f98441 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -1180,8 +1180,10 @@ static int vfio_msi_cap_len(struct vfio_pci_device *vdev, u8 pos)
                 return -ENOMEM;
 
         ret = init_pci_cap_msi_perm(vdev->msi_perm, len, flags);
-        if (ret)
+        if (ret) {
+                kfree(vdev->msi_perm);
                 return ret;
+        }
 
         return len;
 }
@@ -1610,6 +1612,15 @@ static int vfio_ecap_init(struct vfio_pci_device *vdev)
 }
 
 /*
+ * Nag about hardware bugs, hopefully to have vendors fix them, but at least
+ * to collect a list of dependencies for the VF INTx pin quirk below.
+ */
+static const struct pci_device_id known_bogus_vf_intx_pin[] = {
+        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x270c) },
+        {}
+};
+
+/*
  * For each device we allocate a pci_config_map that indicates the
  * capability occupying each dword and thus the struct perm_bits we
  * use for read and write.  We also allocate a virtualized config
@@ -1674,6 +1685,24 @@ int vfio_config_init(struct vfio_pci_device *vdev)
         if (pdev->is_virtfn) {
                 *(__le16 *)&vconfig[PCI_VENDOR_ID] = cpu_to_le16(pdev->vendor);
                 *(__le16 *)&vconfig[PCI_DEVICE_ID] = cpu_to_le16(pdev->device);
+
+                /*
+                 * Per SR-IOV spec rev 1.1, 3.4.1.18 the interrupt pin register
+                 * does not apply to VFs and VFs must implement this register
+                 * as read-only with value zero.  Userspace is not readily able
+                 * to identify whether a device is a VF and thus that the pin
+                 * definition on the device is bogus should it violate this
+                 * requirement.  We already virtualize the pin register for
+                 * other purposes, so we simply need to replace the bogus value
+                 * and consider VFs when we determine INTx IRQ count.
+                 */
+                if (vconfig[PCI_INTERRUPT_PIN] &&
+                    !pci_match_id(known_bogus_vf_intx_pin, pdev))
+                        pci_warn(pdev,
+                                 "Hardware bug: VF reports bogus INTx pin %d\n",
+                                 vconfig[PCI_INTERRUPT_PIN]);
+
+                vconfig[PCI_INTERRUPT_PIN] = 0; /* Gratuitous for good VFs */
         }
 
         if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) || vdev->nointx)
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index f378b9802d8b..813102810f53 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -303,6 +303,56 @@ struct vfio_region_info_cap_type {
 #define VFIO_REGION_SUBTYPE_INTEL_IGD_HOST_CFG  (2)
 #define VFIO_REGION_SUBTYPE_INTEL_IGD_LPC_CFG   (3)
 
+#define VFIO_REGION_TYPE_GFX                    (1)
+#define VFIO_REGION_SUBTYPE_GFX_EDID            (1)
+
+/**
+ * struct vfio_region_gfx_edid - EDID region layout.
+ *
+ * Set display link state and EDID blob.
+ *
+ * The EDID blob has monitor information such as brand, name, serial
+ * number, physical size, supported video modes and more.
+ *
+ * This special region allows userspace (typically qemu) set a virtual
+ * EDID for the virtual monitor, which allows a flexible display
+ * configuration.
+ *
+ * For the edid blob spec look here:
+ *    https://en.wikipedia.org/wiki/Extended_Display_Identification_Data
+ *
+ * On linux systems you can find the EDID blob in sysfs:
+ *    /sys/class/drm/${card}/${connector}/edid
+ *
+ * You can use the edid-decode ulility (comes with xorg-x11-utils) to
+ * decode the EDID blob.
+ *
+ * @edid_offset: location of the edid blob, relative to the
+ *               start of the region (readonly).
+ * @edid_max_size: max size of the edid blob (readonly).
+ * @edid_size: actual edid size (read/write).
+ * @link_state: display link state (read/write).
+ * VFIO_DEVICE_GFX_LINK_STATE_UP: Monitor is turned on.
+ * VFIO_DEVICE_GFX_LINK_STATE_DOWN: Monitor is turned off.
+ * @max_xres: max display width (0 == no limitation, readonly).
+ * @max_yres: max display height (0 == no limitation, readonly).
+ *
+ * EDID update protocol:
+ *   (1) set link-state to down.
+ *   (2) update edid blob and size.
+ *   (3) set link-state to up.
+ */
+struct vfio_region_gfx_edid {
+        __u32 edid_offset;
+        __u32 edid_max_size;
+        __u32 edid_size;
+        __u32 max_xres;
+        __u32 max_yres;
+        __u32 link_state;
+#define VFIO_DEVICE_GFX_LINK_STATE_UP    1
+#define VFIO_DEVICE_GFX_LINK_STATE_DOWN  2
+};
+
 /*
  * The MSIX mappable capability informs that MSIX data of a BAR can be mmapped
  * which allows direct access to non-MSIX registers which happened to be within
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 2535c3677c7b..ca7960adf5a3 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -71,11 +71,19 @@
 #define MBOCHS_NAME               "mbochs"
 #define MBOCHS_CLASS_NAME         "mbochs"
 
+#define MBOCHS_EDID_REGION_INDEX  VFIO_PCI_NUM_REGIONS
+#define MBOCHS_NUM_REGIONS        (MBOCHS_EDID_REGION_INDEX+1)
+
 #define MBOCHS_CONFIG_SPACE_SIZE  0xff
 #define MBOCHS_MMIO_BAR_OFFSET    PAGE_SIZE
 #define MBOCHS_MMIO_BAR_SIZE      PAGE_SIZE
-#define MBOCHS_MEMORY_BAR_OFFSET  (MBOCHS_MMIO_BAR_OFFSET + \
+#define MBOCHS_EDID_OFFSET        (MBOCHS_MMIO_BAR_OFFSET +     \
                                    MBOCHS_MMIO_BAR_SIZE)
+#define MBOCHS_EDID_SIZE          PAGE_SIZE
+#define MBOCHS_MEMORY_BAR_OFFSET  (MBOCHS_EDID_OFFSET + \
+                                   MBOCHS_EDID_SIZE)
+
+#define MBOCHS_EDID_BLOB_OFFSET   (MBOCHS_EDID_SIZE/2)
 
 #define STORE_LE16(addr, val)   (*(u16 *)addr = val)
 #define STORE_LE32(addr, val)   (*(u32 *)addr = val)
@@ -95,16 +103,24 @@ MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
 static const struct mbochs_type {
         const char *name;
         u32 mbytes;
+        u32 max_x;
+        u32 max_y;
 } mbochs_types[] = {
         {
                 .name   = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
                 .mbytes = 4,
+                .max_x  = 800,
+                .max_y  = 600,
         }, {
                 .name   = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
                 .mbytes = 16,
+                .max_x  = 1920,
+                .max_y  = 1440,
         }, {
                 .name   = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
                 .mbytes = 64,
+                .max_x  = 0,
+                .max_y  = 0,
         },
 };
 
@@ -115,6 +131,11 @@ static struct cdev	mbochs_cdev;
 static struct device    mbochs_dev;
 static int              mbochs_used_mbytes;
 
+struct vfio_region_info_ext {
+        struct vfio_region_info          base;
+        struct vfio_region_info_cap_type type;
+};
+
 struct mbochs_mode {
         u32 drm_format;
         u32 bytepp;
@@ -144,13 +165,14 @@ struct mdev_state {
         u32 memory_bar_mask;
         struct mutex ops_lock;
         struct mdev_device *mdev;
-        struct vfio_device_info dev_info;
 
         const struct mbochs_type *type;
         u16 vbe[VBE_DISPI_INDEX_COUNT];
         u64 memsize;
         struct page **pages;
         pgoff_t pagecount;
+        struct vfio_region_gfx_edid edid_regs;
+        u8 edid_blob[0x400];
 
         struct list_head dmabufs;
         u32 active_id;
@@ -342,10 +364,20 @@ static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
                              char *buf, u32 count)
 {
         struct device *dev = mdev_dev(mdev_state->mdev);
+        struct vfio_region_gfx_edid *edid;
         u16 reg16 = 0;
         int index;
 
         switch (offset) {
+        case 0x000 ... 0x3ff: /* edid block */
+                edid = &mdev_state->edid_regs;
+                if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP ||
+                    offset >= edid->edid_size) {
+                        memset(buf, 0, count);
+                        break;
+                }
+                memcpy(buf, mdev_state->edid_blob + offset, count);
+                break;
         case 0x500 ... 0x515: /* bochs dispi interface */
                 if (count != 2)
                         goto unhandled;
@@ -365,6 +397,44 @@ unhandled:
         }
 }
 
+static void handle_edid_regs(struct mdev_state *mdev_state, u16 offset,
+                             char *buf, u32 count, bool is_write)
+{
+        char *regs = (void *)&mdev_state->edid_regs;
+
+        if (offset + count > sizeof(mdev_state->edid_regs))
+                return;
+        if (count != 4)
+                return;
+        if (offset % 4)
+                return;
+
+        if (is_write) {
+                switch (offset) {
+                case offsetof(struct vfio_region_gfx_edid, link_state):
+                case offsetof(struct vfio_region_gfx_edid, edid_size):
+                        memcpy(regs + offset, buf, count);
+                        break;
+                default:
+                        /* read-only regs */
+                        break;
+                }
+        } else {
+                memcpy(buf, regs + offset, count);
+        }
+}
+
+static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
+                             char *buf, u32 count, bool is_write)
+{
+        if (offset + count > mdev_state->edid_regs.edid_max_size)
+                return;
+        if (is_write)
+                memcpy(mdev_state->edid_blob + offset, buf, count);
+        else
+                memcpy(buf, mdev_state->edid_blob + offset, count);
+}
+
 static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
                            loff_t pos, bool is_write)
 {
@@ -384,13 +454,25 @@ static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
                         memcpy(buf, (mdev_state->vconfig + pos), count);
 
         } else if (pos >= MBOCHS_MMIO_BAR_OFFSET &&
-                   pos + count <= MBOCHS_MEMORY_BAR_OFFSET) {
+                   pos + count <= (MBOCHS_MMIO_BAR_OFFSET +
+                                   MBOCHS_MMIO_BAR_SIZE)) {
                 pos -= MBOCHS_MMIO_BAR_OFFSET;
                 if (is_write)
                         handle_mmio_write(mdev_state, pos, buf, count);
                 else
                         handle_mmio_read(mdev_state, pos, buf, count);
 
+        } else if (pos >= MBOCHS_EDID_OFFSET &&
+                   pos + count <= (MBOCHS_EDID_OFFSET +
+                                   MBOCHS_EDID_SIZE)) {
+                pos -= MBOCHS_EDID_OFFSET;
+                if (pos < MBOCHS_EDID_BLOB_OFFSET) {
+                        handle_edid_regs(mdev_state, pos, buf, count, is_write);
+                } else {
+                        pos -= MBOCHS_EDID_BLOB_OFFSET;
+                        handle_edid_blob(mdev_state, pos, buf, count, is_write);
+                }
+
         } else if (pos >= MBOCHS_MEMORY_BAR_OFFSET &&
                    pos + count <=
                    MBOCHS_MEMORY_BAR_OFFSET + mdev_state->memsize) {
@@ -471,6 +553,10 @@ static int mbochs_create(struct kobject *kobj, struct mdev_device *mdev)
         mdev_state->next_id = 1;
 
         mdev_state->type = type;
+        mdev_state->edid_regs.max_xres = type->max_x;
+        mdev_state->edid_regs.max_yres = type->max_y;
+        mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
+        mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
         mbochs_create_config_space(mdev_state);
         mbochs_reset(mdev);
 
@@ -932,16 +1018,16 @@ static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
 }
 
 static int mbochs_get_region_info(struct mdev_device *mdev,
-                                  struct vfio_region_info *region_info,
-                                  u16 *cap_type_id, void **cap_type)
+                                  struct vfio_region_info_ext *ext)
 {
+        struct vfio_region_info *region_info = &ext->base;
         struct mdev_state *mdev_state;
 
         mdev_state = mdev_get_drvdata(mdev);
         if (!mdev_state)
                 return -EINVAL;
 
-        if (region_info->index >= VFIO_PCI_NUM_REGIONS)
+        if (region_info->index >= MBOCHS_NUM_REGIONS)
                 return -EINVAL;
 
         switch (region_info->index) {
@@ -964,6 +1050,20 @@ static int mbochs_get_region_info(struct mdev_device *mdev,
                 region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
                                        VFIO_REGION_INFO_FLAG_WRITE);
                 break;
+        case MBOCHS_EDID_REGION_INDEX:
+                ext->base.argsz = sizeof(*ext);
+                ext->base.offset = MBOCHS_EDID_OFFSET;
+                ext->base.size = MBOCHS_EDID_SIZE;
+                ext->base.flags = (VFIO_REGION_INFO_FLAG_READ  |
+                                   VFIO_REGION_INFO_FLAG_WRITE |
+                                   VFIO_REGION_INFO_FLAG_CAPS);
+                ext->base.cap_offset = offsetof(typeof(*ext), type);
+                ext->type.header.id = VFIO_REGION_INFO_CAP_TYPE;
+                ext->type.header.version = 1;
+                ext->type.header.next = 0;
+                ext->type.type = VFIO_REGION_TYPE_GFX;
+                ext->type.subtype = VFIO_REGION_SUBTYPE_GFX_EDID;
+                break;
         default:
                 region_info->size   = 0;
                 region_info->offset = 0;
@@ -984,7 +1084,7 @@ static int mbochs_get_device_info(struct mdev_device *mdev,
                                   struct vfio_device_info *dev_info)
 {
         dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
-        dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
+        dev_info->num_regions = MBOCHS_NUM_REGIONS;
         dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
         return 0;
 }
@@ -1084,7 +1184,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                         unsigned long arg)
 {
         int ret = 0;
-        unsigned long minsz;
+        unsigned long minsz, outsz;
         struct mdev_state *mdev_state;
 
         mdev_state = mdev_get_drvdata(mdev);
@@ -1106,8 +1206,6 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                 if (ret)
                         return ret;
 
-                memcpy(&mdev_state->dev_info, &info, sizeof(info));
-
                 if (copy_to_user((void __user *)arg, &info, minsz))
                         return -EFAULT;
 
@@ -1115,24 +1213,24 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
         }
         case VFIO_DEVICE_GET_REGION_INFO:
         {
-                struct vfio_region_info info;
-                u16 cap_type_id = 0;
-                void *cap_type = NULL;
+                struct vfio_region_info_ext info;
 
-                minsz = offsetofend(struct vfio_region_info, offset);
+                minsz = offsetofend(typeof(info), base.offset);
 
                 if (copy_from_user(&info, (void __user *)arg, minsz))
                         return -EFAULT;
 
-                if (info.argsz < minsz)
+                outsz = info.base.argsz;
+                if (outsz < minsz)
+                        return -EINVAL;
+                if (outsz > sizeof(info))
                         return -EINVAL;
 
-                ret = mbochs_get_region_info(mdev, &info, &cap_type_id,
-                                           &cap_type);
+                ret = mbochs_get_region_info(mdev, &info);
                 if (ret)
                         return ret;
 
-                if (copy_to_user((void __user *)arg, &info, minsz))
+                if (copy_to_user((void __user *)arg, &info, outsz))
                         return -EFAULT;
 
                 return 0;
@@ -1148,7 +1246,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                         return -EFAULT;
 
                 if ((info.argsz < minsz) ||
-                    (info.index >= mdev_state->dev_info.num_irqs))
+                    (info.index >= VFIO_PCI_NUM_IRQS))
                         return -EINVAL;
 
                 ret = mbochs_get_irq_info(mdev, &info);