On Mon, 9 Apr 2018 12:35:13 +0200
Gerd Hoffmann <kraxel@xxxxxxxxxx> wrote:
> 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
A bit more checkpatch error heavy on this one, I won't point out each
one, but please try to resolve them where appropriate.
> 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
I like that you're using region offsets other than the algorithm
vfio-pci uses, helps to weed out users that assume a region number to
offset mapping rather than consuming the offset field of region info.
> +#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);
As with the region version, BAR0 doesn't actually seem to support
read(2)/write(2).
Nice set of drivers, thanks for providing these as samples! Thanks,
Alex
> + 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
