From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932822AbeDXDFm (ORCPT ); Mon, 23 Apr 2018 23:05:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59366 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932753AbeDXDFg (ORCPT ); Mon, 23 Apr 2018 23:05:36 -0400 Date: Mon, 23 Apr 2018 21:05:31 -0600 From: Alex Williamson To: Gerd Hoffmann Cc: kvm@vger.kernel.org, kwankhede@nvidia.com, linux-kernel@vger.kernel.org (open list) Subject: Re: [PATCH 3/3] sample: vfio bochs vbe display (host device for bochs-drm) Message-ID: <20180423210531.43f9cce1@w520.home> In-Reply-To: <20180409103513.8020-4-kraxel@redhat.com> References: <20180409103513.8020-1-kraxel@redhat.com> <20180409103513.8020-4-kraxel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 9 Apr 2018 12:35:13 +0200 Gerd Hoffmann 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 > --- > 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 > + * > + * based on mtty driver which is: > + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. > + * Author: Neo Jia > + * Kirti Wankhede > + * > + * 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 > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > + > +#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