Display device, demo-ing the vfio dmabuf display interface
(VFIO_GFX_PLANE_TYPE_DMABUF). Compatible enough to qemu stdvga
that bochs-drm.ko can be used as guest driver.
Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
---
samples/vfio-mdev/mbochs.c | 1379 ++++++++++++++++++++++++++++++++++++++++++++
samples/Kconfig | 13 +
samples/vfio-mdev/Makefile | 1 +
3 files changed, 1393 insertions(+)
create mode 100644 samples/vfio-mdev/mbochs.c
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
new file mode 100644
index 0000000000..fc91523190
--- /dev/null
+++ b/samples/vfio-mdev/mbochs.c
@@ -0,0 +1,1379 @@
+/*
+ * Mediated virtual PCI display host device driver
+ *
+ * Emulate enough of qemu stdvga to make bochs-drm.ko happy. That is
+ * basically the vram memory bar and the bochs dispi interface vbe
+ * registers in the mmio register bar. Specifically it does *not*
+ * include any legacy vga stuff. Device looks alot like "qemu -device
+ * secondary-vga".
+ *
+ * (c) Gerd Hoffmann <kraxel@xxxxxxxxxx>
+ *
+ * based on mtty driver which is:
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@xxxxxxxxxx>
+ * Kirti Wankhede <kwankhede@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/cdev.h>
+#include <linux/vfio.h>
+#include <linux/iommu.h>
+#include <linux/sysfs.h>
+#include <linux/mdev.h>
+#include <linux/pci.h>
+#include <linux/dma-buf.h>
+#include <linux/highmem.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_rect.h>
+#include <drm/drm_modeset_lock.h>
+#include <drm/drm_plane.h>
+
+
+#define VBE_DISPI_INDEX_ID 0x0
+#define VBE_DISPI_INDEX_XRES 0x1
+#define VBE_DISPI_INDEX_YRES 0x2
+#define VBE_DISPI_INDEX_BPP 0x3
+#define VBE_DISPI_INDEX_ENABLE 0x4
+#define VBE_DISPI_INDEX_BANK 0x5
+#define VBE_DISPI_INDEX_VIRT_WIDTH 0x6
+#define VBE_DISPI_INDEX_VIRT_HEIGHT 0x7
+#define VBE_DISPI_INDEX_X_OFFSET 0x8
+#define VBE_DISPI_INDEX_Y_OFFSET 0x9
+#define VBE_DISPI_INDEX_VIDEO_MEMORY_64K 0xa
+#define VBE_DISPI_INDEX_COUNT 0xb
+
+#define VBE_DISPI_ID0 0xB0C0
+#define VBE_DISPI_ID1 0xB0C1
+#define VBE_DISPI_ID2 0xB0C2
+#define VBE_DISPI_ID3 0xB0C3
+#define VBE_DISPI_ID4 0xB0C4
+#define VBE_DISPI_ID5 0xB0C5
+
+#define VBE_DISPI_DISABLED 0x00
+#define VBE_DISPI_ENABLED 0x01
+#define VBE_DISPI_GETCAPS 0x02
+#define VBE_DISPI_8BIT_DAC 0x20
+#define VBE_DISPI_LFB_ENABLED 0x40
+#define VBE_DISPI_NOCLEARMEM 0x80
+
+
+#define MBOCHS_NAME "mbochs"
+#define MBOCHS_CLASS_NAME "mbochs"
+
+#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 + MBOCHS_MMIO_BAR_SIZE)
+
+#define STORE_LE16(addr, val) (*(u16 *)addr = val)
+#define STORE_LE32(addr, val) (*(u32 *)addr = val)
+
+
+MODULE_LICENSE("GPL v2");
+
+static int max_mbytes = 256;
+module_param_named(count, max_mbytes, int, 0444);
+MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
+
+
+#define MBOCHS_TYPE_1 "small"
+#define MBOCHS_TYPE_2 "medium"
+#define MBOCHS_TYPE_3 "large"
+
+static const struct mbochs_type {
+ const char *name;
+ u32 mbytes;
+} mbochs_types[] = {
+ {
+ .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
+ .mbytes = 4,
+ },{
+ .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
+ .mbytes = 16,
+ },{
+ .name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
+ .mbytes = 64,
+ },
+};
+
+
+static dev_t mbochs_devt;
+static struct class *mbochs_class;
+static struct cdev mbochs_cdev;
+static struct device mbochs_dev;
+static int mbochs_used_mbytes;
+
+struct mbochs_mode {
+ u32 drm_format;
+ u32 bytepp;
+ u32 width;
+ u32 height;
+ u32 stride;
+ u32 __pad;
+ u64 offset;
+ u64 size;
+};
+
+struct mbochs_dmabuf {
+ struct mbochs_mode mode;
+ u32 id;
+ struct page **pages;
+ pgoff_t pagecount;
+ struct dma_buf *buf;
+ struct mdev_state *mdev_state;
+ struct list_head next;
+ bool unlinked;
+};
+
+/* State of each mdev device */
+struct mdev_state {
+ u8 *vconfig;
+ u64 bar_mask[3];
+ 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 list_head dmabufs;
+ u32 active_id;
+ u32 next_id;
+};
+
+static const char *vbe_name_list[VBE_DISPI_INDEX_COUNT] = {
+ [ VBE_DISPI_INDEX_ID ] = "id",
+ [ VBE_DISPI_INDEX_XRES ] = "xres",
+ [ VBE_DISPI_INDEX_YRES ] = "yres",
+ [ VBE_DISPI_INDEX_BPP ] = "bpp",
+ [ VBE_DISPI_INDEX_ENABLE ] = "enable",
+ [ VBE_DISPI_INDEX_BANK ] = "bank",
+ [ VBE_DISPI_INDEX_VIRT_WIDTH ] = "virt-width",
+ [ VBE_DISPI_INDEX_VIRT_HEIGHT ] = "virt-height",
+ [ VBE_DISPI_INDEX_X_OFFSET ] = "x-offset",
+ [ VBE_DISPI_INDEX_Y_OFFSET ] = "y-offset",
+ [ VBE_DISPI_INDEX_VIDEO_MEMORY_64K ] = "video-mem",
+};
+
+static const char *vbe_name(u32 index)
+{
+ if (index < ARRAY_SIZE(vbe_name_list))
+ return vbe_name_list[index];
+ return "(invalid)";
+}
+
+static const struct mbochs_type *mbochs_find_type(struct kobject *kobj)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(mbochs_types); i++)
+ if (strcmp(mbochs_types[i].name, kobj->name) == 0)
+ return mbochs_types + i;
+ return NULL;
+}
+
+static void mbochs_create_config_space(struct mdev_state *mdev_state)
+{
+ STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID],
+ 0x1234);
+ STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID],
+ 0x1111);
+ STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID],
+ PCI_SUBVENDOR_ID_REDHAT_QUMRANET);
+ STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID],
+ PCI_SUBDEVICE_ID_QEMU);
+
+ STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND],
+ PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
+ STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE],
+ PCI_CLASS_DISPLAY_OTHER);
+ mdev_state->vconfig[PCI_CLASS_REVISION] = 0x01;
+
+ STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0],
+ PCI_BASE_ADDRESS_SPACE_MEMORY |
+ PCI_BASE_ADDRESS_MEM_TYPE_32 |
+ PCI_BASE_ADDRESS_MEM_PREFETCH);
+ mdev_state->bar_mask[0] = ~(mdev_state->memsize) + 1;
+
+ STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_2],
+ PCI_BASE_ADDRESS_SPACE_MEMORY |
+ PCI_BASE_ADDRESS_MEM_TYPE_32);
+ mdev_state->bar_mask[2] = ~(MBOCHS_MMIO_BAR_SIZE) + 1;
+}
+
+static int mbochs_check_framebuffer(struct mdev_state *mdev_state,
+ struct mbochs_mode *mode)
+{
+ struct device *dev = mdev_dev(mdev_state->mdev);
+ u16 *vbe = mdev_state->vbe;
+ u32 virt_width;
+
+ WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
+
+ if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED))
+ goto nofb;
+
+ memset(mode, 0, sizeof(*mode));
+ switch (vbe[VBE_DISPI_INDEX_BPP]) {
+ case 32:
+ mode->drm_format = DRM_FORMAT_XRGB8888;
+ mode->bytepp = 4;
+ break;
+ default:
+ dev_info_ratelimited(dev, "%s: bpp %d not supported\n", __func__,
+ vbe[VBE_DISPI_INDEX_BPP]);
+ goto nofb;
+ }
+
+ mode->width = vbe[VBE_DISPI_INDEX_XRES];
+ mode->height = vbe[VBE_DISPI_INDEX_YRES];
+ virt_width = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
+ if (virt_width < mode->width)
+ virt_width = mode->width;
+ mode->stride = virt_width * mode->bytepp;
+ mode->size = (u64)mode->stride * mode->height;
+ mode->offset = ((u64)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
+ (u64)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
+
+ if (mode->width < 64 || mode->height < 64) {
+ dev_info_ratelimited(dev, "%s: invalid resolution %dx%d\n",
+ __func__, mode->width, mode->height);
+ goto nofb;
+ }
+ if (mode->offset + mode->size > mdev_state->memsize) {
+ dev_info_ratelimited(dev, "%s: framebuffer memory overflow\n",
+ __func__);
+ goto nofb;
+ }
+
+ return 0;
+
+nofb:
+ memset(mode, 0, sizeof(*mode));
+ return -EINVAL;
+}
+
+static bool mbochs_modes_equal(struct mbochs_mode *mode1,
+ struct mbochs_mode *mode2)
+{
+ return memcmp(mode1, mode2, sizeof(struct mbochs_mode)) == 0;
+}
+
+static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
+ char *buf, u32 count)
+{
+ struct device *dev = mdev_dev(mdev_state->mdev);
+ int index = (offset - PCI_BASE_ADDRESS_0) / 0x04;
+ u32 cfg_addr;
+
+ switch (offset) {
+ case PCI_BASE_ADDRESS_0:
+ case PCI_BASE_ADDRESS_2:
+ cfg_addr = *(u32 *)buf;
+
+ if (cfg_addr == 0xffffffff) {
+ cfg_addr = (cfg_addr & mdev_state->bar_mask[index]);
+ } else {
+ cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK;
+ if (cfg_addr)
+ dev_info(dev, "BAR #%d @ 0x%x\n",
+ index, cfg_addr);
+ }
+
+ cfg_addr |= (mdev_state->vconfig[offset] &
+ ~PCI_BASE_ADDRESS_MEM_MASK);
+ STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
+ break;
+ }
+}
+
+static void handle_mmio_write(struct mdev_state *mdev_state, u16 offset,
+ char *buf, u32 count)
+{
+ struct device *dev = mdev_dev(mdev_state->mdev);
+ int index;
+ u16 reg16;
+
+ switch (offset) {
+ case 0x400 ... 0x41f: /* vga ioports remapped */
+ goto unhandled;
+ case 0x500 ... 0x515: /* bochs dispi interface */
+ if (count != 2)
+ goto unhandled;
+ index = (offset - 0x500) / 2;
+ reg16 = *(u16*)buf;
+ if (index < ARRAY_SIZE(mdev_state->vbe))
+ mdev_state->vbe[index] = reg16;
+ dev_dbg(dev, "%s: vbe write %d = %d (%s)\n",
+ __func__, index, reg16, vbe_name(index));
+ break;
+ case 0x600 ... 0x607: /* qemu extended regs */
+ goto unhandled;
+ default:
+ unhandled:
+ dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
+ __func__, offset, count);
+ break;
+ }
+}
+
+static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
+ char *buf, u32 count)
+{
+ struct device *dev = mdev_dev(mdev_state->mdev);
+ u16 reg16 = 0;
+ int index;
+
+ switch (offset) {
+ case 0x500 ... 0x515: /* bochs dispi interface */
+ if (count != 2)
+ goto unhandled;
+ index = (offset - 0x500) / 2;
+ if (index < ARRAY_SIZE(mdev_state->vbe))
+ reg16 = mdev_state->vbe[index];
+ dev_dbg(dev, "%s: vbe read %d = %d (%s)\n",
+ __func__, index, reg16, vbe_name(index));
+ *(u16*)buf = reg16;
+ break;
+ default:
+ unhandled:
+ dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
+ __func__, offset, count);
+ memset(buf, 0, count);
+ break;
+ }
+}
+
+static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
+ loff_t pos, bool is_write)
+{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ struct device *dev = mdev_dev(mdev);
+ int ret = 0;
+
+ mutex_lock(&mdev_state->ops_lock);
+
+ if (pos < MBOCHS_CONFIG_SPACE_SIZE) {
+ if (is_write) {
+ handle_pci_cfg_write(mdev_state, pos, buf, count);
+ } else {
+ memcpy(buf, (mdev_state->vconfig + pos), count);
+ }
+
+ } else if (pos >= MBOCHS_MMIO_BAR_OFFSET &&
+ pos + count < MBOCHS_MEMORY_BAR_OFFSET) {
+ 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 {
+ dev_dbg(dev, "%s: %s @0x%llx (unhandled)\n",
+ __func__, is_write ? "WR" : "RD", pos);
+ ret = -1;
+ goto accessfailed;
+ }
+
+ ret = count;
+
+
+accessfailed:
+ mutex_unlock(&mdev_state->ops_lock);
+
+ return ret;
+}
+
+int mbochs_reset(struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ u32 size64k = mdev_state->memsize / (64 * 1024);
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(mdev_state->vbe); i++)
+ mdev_state->vbe[i] = 0;
+ mdev_state->vbe[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;
+ mdev_state->vbe[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = size64k;
+ return 0;
+}
+
+int mbochs_create(struct kobject *kobj, struct mdev_device *mdev)
+{
+ const struct mbochs_type *type = mbochs_find_type(kobj);
+ struct device *dev = mdev_dev(mdev);
+ struct mdev_state *mdev_state;
+
+ if (!type)
+ type = &mbochs_types[0];
+ if (type->mbytes + mbochs_used_mbytes > max_mbytes)
+ return -ENOMEM;
+
+ mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
+ if (mdev_state == NULL)
+ return -ENOMEM;
+
+ mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
+ if (mdev_state->vconfig == NULL)
+ goto err_mem;
+
+ mdev_state->memsize = type->mbytes * 1024 * 1024;
+ mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT;
+ mdev_state->pages = kzalloc(mdev_state->pagecount * sizeof(struct page*),
+ GFP_KERNEL);
+ if (!mdev_state->pages)
+ goto err_mem;
+
+ dev_info(dev, "%s: %s, %d MB, %ld pages\n", __func__,
+ kobj->name, type->mbytes, mdev_state->pagecount);
+
+ mutex_init(&mdev_state->ops_lock);
+ mdev_state->mdev = mdev;
+ mdev_set_drvdata(mdev, mdev_state);
+ INIT_LIST_HEAD(&mdev_state->dmabufs);
+ mdev_state->next_id = 1;
+
+ mdev_state->type = type;
+ mbochs_create_config_space(mdev_state);
+ mbochs_reset(mdev);
+
+ mbochs_used_mbytes += type->mbytes;
+ return 0;
+
+err_mem:
+ kfree(mdev_state->vconfig);
+ kfree(mdev_state);
+ return -ENOMEM;
+}
+
+int mbochs_remove(struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+
+ mbochs_used_mbytes -= mdev_state->type->mbytes;
+ mdev_set_drvdata(mdev, NULL);
+ kfree(mdev_state->pages);
+ kfree(mdev_state->vconfig);
+ kfree(mdev_state);
+ return 0;
+}
+
+ssize_t mbochs_read(struct mdev_device *mdev, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ unsigned int done = 0;
+ int ret;
+
+ while (count) {
+ size_t filled;
+
+ if (count >= 4 && !(*ppos % 4)) {
+ u32 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 4;
+ } else if (count >= 2 && !(*ppos % 2)) {
+ u16 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 2;
+ } else {
+ u8 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 1;
+ }
+
+ count -= filled;
+ done += filled;
+ *ppos += filled;
+ buf += filled;
+ }
+
+ return done;
+
+read_err:
+ return -EFAULT;
+}
+
+ssize_t mbochs_write(struct mdev_device *mdev, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ unsigned int done = 0;
+ int ret;
+
+ while (count) {
+ size_t filled;
+
+ if (count >= 4 && !(*ppos % 4)) {
+ u32 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 4;
+ } else if (count >= 2 && !(*ppos % 2)) {
+ u16 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 2;
+ } else {
+ u8 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 1;
+ }
+ count -= filled;
+ done += filled;
+ *ppos += filled;
+ buf += filled;
+ }
+
+ return done;
+write_err:
+ return -EFAULT;
+}
+
+struct page *__mbochs_get_page(struct mdev_state *mdev_state, pgoff_t pgoff)
+{
+ WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
+
+ if (!mdev_state->pages[pgoff]) {
+ mdev_state->pages[pgoff] =
+ alloc_pages(GFP_HIGHUSER | __GFP_ZERO, 0);
+ if (!mdev_state->pages[pgoff])
+ return NULL;
+ }
+
+ get_page(mdev_state->pages[pgoff]);
+ return mdev_state->pages[pgoff];
+}
+
+struct page *mbochs_get_page(struct mdev_state *mdev_state, pgoff_t pgoff)
+{
+ struct page *page;
+
+ if (WARN_ON(pgoff >= mdev_state->pagecount))
+ return NULL;
+
+ mutex_lock(&mdev_state->ops_lock);
+ page = __mbochs_get_page(mdev_state, pgoff);
+ mutex_unlock(&mdev_state->ops_lock);
+
+ return page;
+}
+
+void mbochs_put_pages(struct mdev_state *mdev_state)
+{
+ struct device *dev = mdev_dev(mdev_state->mdev);
+ int i, count = 0;
+
+ WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
+
+ for (i = 0; i < mdev_state->pagecount; i++) {
+ if (!mdev_state->pages[i])
+ continue;
+ put_page(mdev_state->pages[i]);
+ mdev_state->pages[i] = NULL;
+ count++;
+ }
+ dev_dbg(dev, "%s: %d pages released\n", __func__, count);
+}
+
+static int mbochs_region_vm_fault(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct mdev_state *mdev_state = vma->vm_private_data;
+ pgoff_t page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+
+ if (page_offset >= mdev_state->pagecount)
+ return VM_FAULT_SIGBUS;
+
+ vmf->page = mbochs_get_page(mdev_state, page_offset);
+ if (!vmf->page)
+ return VM_FAULT_SIGBUS;
+
+ return 0;
+}
+
+static const struct vm_operations_struct mbochs_region_vm_ops = {
+ .fault = mbochs_region_vm_fault,
+};
+
+int mbochs_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
+{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+
+ if (vma->vm_pgoff != MBOCHS_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
+ return -EINVAL;
+ if (vma->vm_end < vma->vm_start)
+ return -EINVAL;
+ if (vma->vm_end - vma->vm_start > mdev_state->memsize)
+ return -EINVAL;
+ if ((vma->vm_flags & VM_SHARED) == 0)
+ return -EINVAL;
+
+ vma->vm_ops = &mbochs_region_vm_ops;
+ vma->vm_private_data = mdev_state;
+ return 0;
+}
+
+static int mbochs_dmabuf_vm_fault(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct mbochs_dmabuf *dmabuf = vma->vm_private_data;
+
+ if (WARN_ON(vmf->pgoff >= dmabuf->pagecount))
+ return VM_FAULT_SIGBUS;
+
+ vmf->page = dmabuf->pages[vmf->pgoff];
+ get_page(vmf->page);
+ return 0;
+}
+
+static const struct vm_operations_struct mbochs_dmabuf_vm_ops = {
+ .fault = mbochs_dmabuf_vm_fault,
+};
+
+static int mbochs_mmap_dmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
+{
+ struct mbochs_dmabuf *dmabuf = buf->priv;
+ struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
+
+ dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
+
+ if ((vma->vm_flags & VM_SHARED) == 0)
+ return -EINVAL;
+
+ vma->vm_ops = &mbochs_dmabuf_vm_ops;
+ vma->vm_private_data = dmabuf;
+ return 0;
+}
+
+static void mbochs_print_dmabuf(struct mbochs_dmabuf *dmabuf,
+ const char *prefix)
+{
+ struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
+ u32 fourcc = dmabuf->mode.drm_format;
+
+ dev_dbg(dev, "%s/%d: %c%c%c%c, %dx%d, stride %d, off 0x%llx, size 0x%llx, pages %ld\n",
+ prefix, dmabuf->id,
+ fourcc ? ((fourcc >> 0) & 0xff) : '-',
+ fourcc ? ((fourcc >> 8) & 0xff) : '-',
+ fourcc ? ((fourcc >> 16) & 0xff) : '-',
+ fourcc ? ((fourcc >> 24) & 0xff) : '-',
+ dmabuf->mode.width, dmabuf->mode.height, dmabuf->mode.stride,
+ dmabuf->mode.offset, dmabuf->mode.size, dmabuf->pagecount);
+}
+
+static struct sg_table *mbochs_map_dmabuf(struct dma_buf_attachment *at,
+ enum dma_data_direction direction)
+{
+ struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
+ struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
+ struct sg_table *sg;
+
+ dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
+
+ sg = kzalloc(sizeof(*sg), GFP_KERNEL);
+ if (!sg)
+ goto err1;
+ if (sg_alloc_table_from_pages(sg, dmabuf->pages, dmabuf->pagecount,
+ 0, dmabuf->mode.size, GFP_KERNEL) < 0)
+ goto err2;
+ if (!dma_map_sg(at->dev, sg->sgl, sg->nents, direction))
+ goto err3;
+
+ return sg;
+
+err3:
+ sg_free_table(sg);
+err2:
+ kfree(sg);
+err1:
+ return ERR_PTR(-ENOMEM);
+}
+
+static void mbochs_unmap_dmabuf(struct dma_buf_attachment *at,
+ struct sg_table *sg,
+ enum dma_data_direction direction)
+{
+ struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
+ struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
+
+ dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
+
+ sg_free_table(sg);
+ kfree(sg);
+}
+
+static void mbochs_release_dmabuf(struct dma_buf *buf)
+{
+ struct mbochs_dmabuf *dmabuf = buf->priv;
+ struct mdev_state *mdev_state = dmabuf->mdev_state;
+ struct device *dev = mdev_dev(mdev_state->mdev);
+ pgoff_t pg;
+
+ dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
+
+ for (pg = 0; pg < dmabuf->pagecount; pg++)
+ put_page(dmabuf->pages[pg]);
+
+ mutex_lock(&mdev_state->ops_lock);
+ dmabuf->buf = NULL;
+ if (dmabuf->unlinked)
+ kfree(dmabuf);
+ mutex_unlock(&mdev_state->ops_lock);
+}
+
+static void *mbochs_kmap_atomic_dmabuf(struct dma_buf *buf, unsigned long page_num)
+{
+ struct mbochs_dmabuf *dmabuf = buf->priv;
+ struct page *page = dmabuf->pages[page_num];
+
+ return kmap_atomic(page);
+}
+
+static void *mbochs_kmap_dmabuf(struct dma_buf *buf, unsigned long page_num)
+{
+ struct mbochs_dmabuf *dmabuf = buf->priv;
+ struct page *page = dmabuf->pages[page_num];
+
+ return kmap(page);
+}
+
+static struct dma_buf_ops mbochs_dmabuf_ops = {
+ .map_dma_buf = mbochs_map_dmabuf,
+ .unmap_dma_buf = mbochs_unmap_dmabuf,
+ .release = mbochs_release_dmabuf,
+ .map_atomic = mbochs_kmap_atomic_dmabuf,
+ .map = mbochs_kmap_dmabuf,
+ .mmap = mbochs_mmap_dmabuf,
+};
+
+static struct mbochs_dmabuf *mbochs_dmabuf_alloc(struct mdev_state *mdev_state,
+ struct mbochs_mode *mode)
+{
+ struct mbochs_dmabuf *dmabuf;
+ pgoff_t page_offset, pg;
+
+ WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
+
+ dmabuf = kzalloc(sizeof(struct mbochs_dmabuf), GFP_KERNEL);
+ if (!dmabuf)
+ return NULL;
+
+ dmabuf->mode = *mode;
+ dmabuf->id = mdev_state->next_id++;
+ dmabuf->pagecount = DIV_ROUND_UP(mode->size, PAGE_SIZE);
+ dmabuf->pages = kzalloc(dmabuf->pagecount * sizeof(struct page*),
+ GFP_KERNEL);
+ if (!dmabuf->pages)
+ goto err_free_dmabuf;
+
+ page_offset = dmabuf->mode.offset >> PAGE_SHIFT;
+ for (pg = 0; pg < dmabuf->pagecount; pg++) {
+ dmabuf->pages[pg] = __mbochs_get_page(mdev_state, page_offset + pg);
+ if (!dmabuf->pages[pg])
+ goto err_free_pages;
+ }
+
+ dmabuf->mdev_state = mdev_state;
+ list_add(&dmabuf->next, &mdev_state->dmabufs);
+
+ mbochs_print_dmabuf(dmabuf, __func__);
+ return dmabuf;
+
+err_free_pages:
+ while (pg > 0)
+ put_page(dmabuf->pages[--pg]);
+ kfree(dmabuf->pages);
+err_free_dmabuf:
+ kfree(dmabuf);
+ return NULL;
+}
+
+static struct mbochs_dmabuf *
+mbochs_dmabuf_find_by_mode(struct mdev_state *mdev_state,
+ struct mbochs_mode *mode)
+{
+ struct mbochs_dmabuf *dmabuf;
+
+ WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
+
+ list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
+ if (mbochs_modes_equal(&dmabuf->mode, mode))
+ return dmabuf;
+
+ return NULL;
+}
+
+static struct mbochs_dmabuf *
+mbochs_dmabuf_find_by_id(struct mdev_state *mdev_state, u32 id)
+{
+ struct mbochs_dmabuf *dmabuf;
+
+ WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
+
+ list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
+ if (dmabuf->id == id)
+ return dmabuf;
+
+ return NULL;
+}
+
+static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
+{
+ struct mdev_state *mdev_state = dmabuf->mdev_state;
+ struct device *dev = mdev_dev(mdev_state->mdev);
+ DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+ struct dma_buf *buf;
+
+ WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
+
+ if (!IS_ALIGNED(dmabuf->mode.offset, PAGE_SIZE)) {
+ dev_info_ratelimited(dev, "%s: framebuffer not page-aligned\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ exp_info.ops = &mbochs_dmabuf_ops;
+ exp_info.size = dmabuf->mode.size;
+ exp_info.priv = dmabuf;
+
+ buf = dma_buf_export(&exp_info);
+ if (IS_ERR(buf)) {
+ dev_info_ratelimited(dev, "%s: dma_buf_export failed: %ld\n",
+ __func__, PTR_ERR(buf));
+ return PTR_ERR(buf);
+ }
+
+ dmabuf->buf = buf;
+ dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
+ return 0;
+}
+
+int mbochs_get_region_info(struct mdev_device *mdev,
+ struct vfio_region_info *region_info,
+ u16 *cap_type_id, void **cap_type)
+{
+ struct mdev_state *mdev_state;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -EINVAL;
+
+ if (region_info->index >= VFIO_PCI_NUM_REGIONS)
+ return -EINVAL;
+
+ switch (region_info->index) {
+ case VFIO_PCI_CONFIG_REGION_INDEX:
+ region_info->offset = 0;
+ region_info->size = MBOCHS_CONFIG_SPACE_SIZE;
+ region_info->flags = (VFIO_REGION_INFO_FLAG_READ |
+ VFIO_REGION_INFO_FLAG_WRITE);
+ break;
+ case VFIO_PCI_BAR0_REGION_INDEX:
+ region_info->offset = MBOCHS_MEMORY_BAR_OFFSET;
+ region_info->size = mdev_state->memsize;
+ region_info->flags = (VFIO_REGION_INFO_FLAG_READ |
+ VFIO_REGION_INFO_FLAG_WRITE |
+ VFIO_REGION_INFO_FLAG_MMAP);
+ break;
+ case VFIO_PCI_BAR2_REGION_INDEX:
+ region_info->offset = MBOCHS_MMIO_BAR_OFFSET;
+ region_info->size = MBOCHS_MMIO_BAR_SIZE;
+ region_info->flags = (VFIO_REGION_INFO_FLAG_READ |
+ VFIO_REGION_INFO_FLAG_WRITE);
+ break;
+ default:
+ region_info->size = 0;
+ region_info->offset = 0;
+ region_info->flags = 0;
+ }
+
+ return 0;
+}
+
+int mbochs_get_irq_info(struct mdev_device *mdev, struct vfio_irq_info *irq_info)
+{
+ irq_info->count = 0;
+ return 0;
+}
+
+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_irqs = VFIO_PCI_NUM_IRQS;
+ return 0;
+}
+
+int mbochs_query_gfx_plane(struct mdev_device *mdev,
+ struct vfio_device_gfx_plane_info *plane)
+{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ struct device *dev = mdev_dev(mdev);
+ struct mbochs_dmabuf *dmabuf;
+ struct mbochs_mode mode;
+ int ret;
+
+ if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) {
+ if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE |
+ VFIO_GFX_PLANE_TYPE_DMABUF))
+ return 0;
+ return -EINVAL;
+ }
+
+ if (plane->flags != VFIO_GFX_PLANE_TYPE_DMABUF)
+ return -EINVAL;
+
+ plane->drm_format_mod = 0;
+ plane->x_pos = 0;
+ plane->y_pos = 0;
+ plane->x_hot = 0;
+ plane->y_hot = 0;
+
+ mutex_lock(&mdev_state->ops_lock);
+
+ ret = -EINVAL;
+ if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY)
+ ret = mbochs_check_framebuffer(mdev_state, &mode);
+ if (ret < 0) {
+ plane->drm_format = 0;
+ plane->width = 0;
+ plane->height = 0;
+ plane->stride = 0;
+ plane->size = 0;
+ plane->dmabuf_id = 0;
+ goto done;
+ }
+
+ dmabuf = mbochs_dmabuf_find_by_mode(mdev_state, &mode);
+ if (!dmabuf)
+ mbochs_dmabuf_alloc(mdev_state, &mode);
+ if (!dmabuf) {
+ mutex_unlock(&mdev_state->ops_lock);
+ return -ENOMEM;
+ }
+
+ plane->drm_format = dmabuf->mode.drm_format;
+ plane->width = dmabuf->mode.width;
+ plane->height = dmabuf->mode.height;
+ plane->stride = dmabuf->mode.stride;
+ plane->size = dmabuf->mode.size;
+ plane->dmabuf_id = dmabuf->id;
+
+done:
+ if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY &&
+ mdev_state->active_id != plane->dmabuf_id) {
+ dev_dbg(dev, "%s: primary: %d => %d\n", __func__,
+ mdev_state->active_id, plane->dmabuf_id);
+ mdev_state->active_id = plane->dmabuf_id;
+ }
+ mutex_unlock(&mdev_state->ops_lock);
+ return 0;
+}
+
+int mbochs_get_gfx_dmabuf(struct mdev_device *mdev,
+ u32 id)
+{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ struct mbochs_dmabuf *dmabuf;
+
+ mutex_lock(&mdev_state->ops_lock);
+
+ dmabuf = mbochs_dmabuf_find_by_id(mdev_state, id);
+ if (!dmabuf) {
+ mutex_unlock(&mdev_state->ops_lock);
+ return -ENOENT;
+ }
+
+ if (!dmabuf->buf)
+ mbochs_dmabuf_export(dmabuf);
+
+ mutex_unlock(&mdev_state->ops_lock);
+
+ if (!dmabuf->buf)
+ return -EINVAL;
+
+ return dma_buf_fd(dmabuf->buf, 0);
+}
+
+static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret = 0;
+ unsigned long minsz;
+ struct mdev_state *mdev_state;
+
+ mdev_state = mdev_get_drvdata(mdev);
+
+ switch (cmd) {
+ case VFIO_DEVICE_GET_INFO:
+ {
+ struct vfio_device_info info;
+
+ minsz = offsetofend(struct vfio_device_info, num_irqs);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ ret = mbochs_get_device_info(mdev, &info);
+ if (ret)
+ return ret;
+
+ memcpy(&mdev_state->dev_info, &info, sizeof(info));
+
+ if (copy_to_user((void __user *)arg, &info, minsz))
+ return -EFAULT;
+
+ return 0;
+ }
+ case VFIO_DEVICE_GET_REGION_INFO:
+ {
+ struct vfio_region_info info;
+ u16 cap_type_id = 0;
+ void *cap_type = NULL;
+
+ minsz = offsetofend(struct vfio_region_info, offset);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ ret = mbochs_get_region_info(mdev, &info, &cap_type_id,
+ &cap_type);
+ if (ret)
+ return ret;
+
+ if (copy_to_user((void __user *)arg, &info, minsz))
+ return -EFAULT;
+
+ return 0;
+ }
+
+ case VFIO_DEVICE_GET_IRQ_INFO:
+ {
+ struct vfio_irq_info info;
+
+ minsz = offsetofend(struct vfio_irq_info, count);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if ((info.argsz < minsz) ||
+ (info.index >= mdev_state->dev_info.num_irqs))
+ return -EINVAL;
+
+ ret = mbochs_get_irq_info(mdev, &info);
+ if (ret)
+ return ret;
+
+ if (copy_to_user((void __user *)arg, &info, minsz))
+ return -EFAULT;
+
+ return 0;
+ }
+
+ case VFIO_DEVICE_QUERY_GFX_PLANE:
+ {
+ struct vfio_device_gfx_plane_info plane;
+
+ minsz = offsetofend(struct vfio_device_gfx_plane_info,
+ region_index);
+
+ if (copy_from_user(&plane, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (plane.argsz < minsz)
+ return -EINVAL;
+
+ ret = mbochs_query_gfx_plane(mdev, &plane);
+ if (ret)
+ return ret;
+
+ if (copy_to_user((void __user *)arg, &plane, minsz))
+ return -EFAULT;
+
+ return 0;
+ }
+
+ case VFIO_DEVICE_GET_GFX_DMABUF:
+ {
+ u32 dmabuf_id;
+
+ if (get_user(dmabuf_id, (__u32 __user *)arg))
+ return -EFAULT;
+
+ return mbochs_get_gfx_dmabuf(mdev, dmabuf_id);
+ }
+
+ case VFIO_DEVICE_SET_IRQS:
+ return -EINVAL;
+
+ case VFIO_DEVICE_RESET:
+ return mbochs_reset(mdev);
+ }
+ return -ENOTTY;
+}
+
+int mbochs_open(struct mdev_device *mdev)
+{
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ return 0;
+}
+
+void mbochs_close(struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ struct mbochs_dmabuf *dmabuf, *tmp;
+
+ mutex_lock(&mdev_state->ops_lock);
+
+ list_for_each_entry_safe(dmabuf, tmp, &mdev_state->dmabufs, next) {
+ list_del(&dmabuf->next);
+ if (dmabuf->buf) {
+ /* free in mbochs_release_dmabuf() */
+ dmabuf->unlinked = true;
+ } else {
+ kfree(dmabuf);
+ }
+ }
+ mbochs_put_pages(mdev_state);
+
+ mutex_unlock(&mdev_state->ops_lock);
+ module_put(THIS_MODULE);
+}
+
+static ssize_t
+memory_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct mdev_device *mdev = mdev_from_dev(dev);
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+
+ return sprintf(buf, "%d MB\n", mdev_state->type->mbytes);
+}
+static DEVICE_ATTR_RO(memory);
+
+static struct attribute *mdev_dev_attrs[] = {
+ &dev_attr_memory.attr,
+ NULL,
+};
+
+static const struct attribute_group mdev_dev_group = {
+ .name = "vendor",
+ .attrs = mdev_dev_attrs,
+};
+
+const struct attribute_group *mdev_dev_groups[] = {
+ &mdev_dev_group,
+ NULL,
+};
+
+static ssize_t
+name_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+ return sprintf(buf, "%s\n", kobj->name);
+}
+MDEV_TYPE_ATTR_RO(name);
+
+static ssize_t
+description_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+ const struct mbochs_type *type = mbochs_find_type(kobj);
+
+ return sprintf(buf, "virtual display, %d MB video memory\n",
+ type ? type->mbytes : 0);
+}
+MDEV_TYPE_ATTR_RO(description);
+
+static ssize_t
+available_instances_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+ const struct mbochs_type *type = mbochs_find_type(kobj);
+ int count = (max_mbytes - mbochs_used_mbytes) / type->mbytes;
+
+ return sprintf(buf, "%d\n", count);
+}
+MDEV_TYPE_ATTR_RO(available_instances);
+
+static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
+ char *buf)
+{
+ return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
+}
+MDEV_TYPE_ATTR_RO(device_api);
+
+static struct attribute *mdev_types_attrs[] = {
+ &mdev_type_attr_name.attr,
+ &mdev_type_attr_description.attr,
+ &mdev_type_attr_device_api.attr,
+ &mdev_type_attr_available_instances.attr,
+ NULL,
+};
+
+static struct attribute_group mdev_type_group1 = {
+ .name = MBOCHS_TYPE_1,
+ .attrs = mdev_types_attrs,
+};
+
+static struct attribute_group mdev_type_group2 = {
+ .name = MBOCHS_TYPE_2,
+ .attrs = mdev_types_attrs,
+};
+
+static struct attribute_group mdev_type_group3 = {
+ .name = MBOCHS_TYPE_3,
+ .attrs = mdev_types_attrs,
+};
+
+static struct attribute_group *mdev_type_groups[] = {
+ &mdev_type_group1,
+ &mdev_type_group2,
+ &mdev_type_group3,
+ NULL,
+};
+
+static const struct mdev_parent_ops mdev_fops = {
+ .owner = THIS_MODULE,
+ .mdev_attr_groups = mdev_dev_groups,
+ .supported_type_groups = mdev_type_groups,
+ .create = mbochs_create,
+ .remove = mbochs_remove,
+ .open = mbochs_open,
+ .release = mbochs_close,
+ .read = mbochs_read,
+ .write = mbochs_write,
+ .ioctl = mbochs_ioctl,
+ .mmap = mbochs_mmap,
+};
+
+static const struct file_operations vd_fops = {
+ .owner = THIS_MODULE,
+};
+
+static void mbochs_device_release(struct device *dev)
+{
+ /* nothing */
+}
+
+static int __init mbochs_dev_init(void)
+{
+ int ret = 0;
+
+ ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK, MBOCHS_NAME);
+ if (ret < 0) {
+ pr_err("Error: failed to register mbochs_dev, err: %d\n", ret);
+ return ret;
+ }
+ cdev_init(&mbochs_cdev, &vd_fops);
+ cdev_add(&mbochs_cdev, mbochs_devt, MINORMASK);
+ pr_info("%s: major %d\n", __func__, MAJOR(mbochs_devt));
+
+ mbochs_class = class_create(THIS_MODULE, MBOCHS_CLASS_NAME);
+ if (IS_ERR(mbochs_class)) {
+ pr_err("Error: failed to register mbochs_dev class\n");
+ ret = PTR_ERR(mbochs_class);
+ goto failed1;
+ }
+ mbochs_dev.class = mbochs_class;
+ mbochs_dev.release = mbochs_device_release;
+ dev_set_name(&mbochs_dev, "%s", MBOCHS_NAME);
+
+ ret = device_register(&mbochs_dev);
+ if (ret)
+ goto failed2;
+
+ ret = mdev_register_device(&mbochs_dev, &mdev_fops);
+ if (ret)
+ goto failed3;
+
+ return 0;
+
+failed3:
+ device_unregister(&mbochs_dev);
+failed2:
+ class_destroy(mbochs_class);
+failed1:
+ cdev_del(&mbochs_cdev);
+ unregister_chrdev_region(mbochs_devt, MINORMASK);
+ return ret;
+}
+
+static void __exit mbochs_dev_exit(void)
+{
+ mbochs_dev.bus = NULL;
+ mdev_unregister_device(&mbochs_dev);
+
+ device_unregister(&mbochs_dev);
+ cdev_del(&mbochs_cdev);
+ unregister_chrdev_region(mbochs_devt, MINORMASK);
+ class_destroy(mbochs_class);
+ mbochs_class = NULL;
+}
+
+module_init(mbochs_dev_init)
+module_exit(mbochs_dev_exit)
diff --git a/samples/Kconfig b/samples/Kconfig
index 755430c788..5de0674cdd 100644
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -128,6 +128,19 @@ config SAMPLE_VFIO_MDEV_MDPY_FB
help
Guest fbdev driver for the virtual display sample driver.
+config SAMPLE_VFIO_MDEV_MBOCHS
+ tristate "Build VFIO mdpy example mediated device sample code -- loadable modules only"
+ depends on VFIO_MDEV_DEVICE && m
+ help
+ Build a virtual display sample driver for use as a VFIO
+ mediated device. It supports the region display interface
+ (VFIO_GFX_PLANE_TYPE_DMABUF).
+ Emulate enough of qemu stdvga to make bochs-drm.ko happy.
+ That is basically the vram memory bar and the bochs dispi
+ interface vbe registers in the mmio register bar.
+ Specifically it does *not* include any legacy vga stuff.
+ Device looks alot like "qemu -device secondary-vga".
+
config SAMPLE_STATX
bool "Build example extended-stat using code"
depends on BROKEN
diff --git a/samples/vfio-mdev/Makefile b/samples/vfio-mdev/Makefile
index 7a5790aaec..7db889ca13 100644
--- a/samples/vfio-mdev/Makefile
+++ b/samples/vfio-mdev/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_SAMPLE_VFIO_MDEV_MTTY) += mtty.o
obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY) += mdpy.o
obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY_FB) += mdpy-fb.o
+obj-$(CONFIG_SAMPLE_VFIO_MDEV_MBOCHS) += mbochs.o
--
2.9.3
