diff options
Diffstat (limited to 'samples/vfio-mdev/mbochs.c')
| -rw-r--r-- | samples/vfio-mdev/mbochs.c | 1471 |
1 files changed, 1471 insertions, 0 deletions
diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c new file mode 100644 index 000000000..117a8d799 --- /dev/null +++ b/samples/vfio-mdev/mbochs.c @@ -0,0 +1,1471 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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 a lot like "qemu -device + * secondary-vga". + * + * (c) Gerd Hoffmann <kraxel@redhat.com> + * + * based on mtty driver which is: + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. + * Author: Neo Jia <cjia@nvidia.com> + * Kirti Wankhede <kwankhede@nvidia.com> + * + * 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/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_property.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_EDID_REGION_INDEX VFIO_PCI_NUM_REGIONS +#define MBOCHS_NUM_REGIONS (MBOCHS_EDID_REGION_INDEX+1) + +#define MBOCHS_CONFIG_SPACE_SIZE 0xff +#define MBOCHS_MMIO_BAR_OFFSET PAGE_SIZE +#define MBOCHS_MMIO_BAR_SIZE PAGE_SIZE +#define MBOCHS_EDID_OFFSET (MBOCHS_MMIO_BAR_OFFSET + \ + MBOCHS_MMIO_BAR_SIZE) +#define MBOCHS_EDID_SIZE PAGE_SIZE +#define MBOCHS_MEMORY_BAR_OFFSET (MBOCHS_EDID_OFFSET + \ + MBOCHS_EDID_SIZE) + +#define MBOCHS_EDID_BLOB_OFFSET (MBOCHS_EDID_SIZE/2) + +#define STORE_LE16(addr, val) (*(u16 *)addr = val) +#define STORE_LE32(addr, val) (*(u32 *)addr = val) + + +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 struct mbochs_type { + struct mdev_type type; + u32 mbytes; + u32 max_x; + u32 max_y; +} mbochs_types[] = { + { + .type.sysfs_name = MBOCHS_TYPE_1, + .type.pretty_name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1, + .mbytes = 4, + .max_x = 800, + .max_y = 600, + }, { + .type.sysfs_name = MBOCHS_TYPE_2, + .type.pretty_name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2, + .mbytes = 16, + .max_x = 1920, + .max_y = 1440, + }, { + .type.sysfs_name = MBOCHS_TYPE_3, + .type.pretty_name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3, + .mbytes = 64, + .max_x = 0, + .max_y = 0, + }, +}; + +static struct mdev_type *mbochs_mdev_types[] = { + &mbochs_types[0].type, + &mbochs_types[1].type, + &mbochs_types[2].type, +}; + +static dev_t mbochs_devt; +static struct class *mbochs_class; +static struct cdev mbochs_cdev; +static struct device mbochs_dev; +static struct mdev_parent mbochs_parent; +static atomic_t mbochs_avail_mbytes; +static const struct vfio_device_ops mbochs_dev_ops; + +struct vfio_region_info_ext { + struct vfio_region_info base; + struct vfio_region_info_cap_type type; +}; + +struct mbochs_mode { + u32 drm_format; + u32 bytepp; + 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 { + struct vfio_device vdev; + u8 *vconfig; + u64 bar_mask[3]; + u32 memory_bar_mask; + struct mutex ops_lock; + struct mdev_device *mdev; + + const struct mbochs_type *type; + u16 vbe[VBE_DISPI_INDEX_COUNT]; + u64 memsize; + struct page **pages; + pgoff_t pagecount; + struct vfio_region_gfx_edid edid_regs; + u8 edid_blob[0x400]; + + struct list_head dmabufs; + u32 active_id; + 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 struct page *__mbochs_get_page(struct mdev_state *mdev_state, + pgoff_t pgoff); +static struct page *mbochs_get_page(struct mdev_state *mdev_state, + pgoff_t pgoff); + +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); + struct vfio_region_gfx_edid *edid; + u16 reg16 = 0; + int index; + + switch (offset) { + case 0x000 ... 0x3ff: /* edid block */ + edid = &mdev_state->edid_regs; + if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP || + offset >= edid->edid_size) { + memset(buf, 0, count); + break; + } + memcpy(buf, mdev_state->edid_blob + offset, count); + break; + case 0x500 ... 0x515: /* bochs dispi interface */ + if (count != 2) + goto unhandled; + 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 void handle_edid_regs(struct mdev_state *mdev_state, u16 offset, + char *buf, u32 count, bool is_write) +{ + char *regs = (void *)&mdev_state->edid_regs; + + if (offset + count > sizeof(mdev_state->edid_regs)) + return; + if (count != 4) + return; + if (offset % 4) + return; + + if (is_write) { + switch (offset) { + case offsetof(struct vfio_region_gfx_edid, link_state): + case offsetof(struct vfio_region_gfx_edid, edid_size): + memcpy(regs + offset, buf, count); + break; + default: + /* read-only regs */ + break; + } + } else { + memcpy(buf, regs + offset, count); + } +} + +static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset, + char *buf, u32 count, bool is_write) +{ + if (offset + count > mdev_state->edid_regs.edid_max_size) + return; + if (is_write) + memcpy(mdev_state->edid_blob + offset, buf, count); + else + memcpy(buf, mdev_state->edid_blob + offset, count); +} + +static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf, + size_t count, loff_t pos, bool is_write) +{ + struct page *pg; + loff_t poff; + char *map; + 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_MMIO_BAR_OFFSET + + MBOCHS_MMIO_BAR_SIZE)) { + pos -= MBOCHS_MMIO_BAR_OFFSET; + if (is_write) + handle_mmio_write(mdev_state, pos, buf, count); + else + handle_mmio_read(mdev_state, pos, buf, count); + + } else if (pos >= MBOCHS_EDID_OFFSET && + pos + count <= (MBOCHS_EDID_OFFSET + + MBOCHS_EDID_SIZE)) { + pos -= MBOCHS_EDID_OFFSET; + if (pos < MBOCHS_EDID_BLOB_OFFSET) { + handle_edid_regs(mdev_state, pos, buf, count, is_write); + } else { + pos -= MBOCHS_EDID_BLOB_OFFSET; + handle_edid_blob(mdev_state, pos, buf, count, is_write); + } + + } else if (pos >= MBOCHS_MEMORY_BAR_OFFSET && + pos + count <= + MBOCHS_MEMORY_BAR_OFFSET + mdev_state->memsize) { + pos -= MBOCHS_MMIO_BAR_OFFSET; + poff = pos & ~PAGE_MASK; + pg = __mbochs_get_page(mdev_state, pos >> PAGE_SHIFT); + map = kmap(pg); + if (is_write) + memcpy(map + poff, buf, count); + else + memcpy(buf, map + poff, count); + kunmap(pg); + put_page(pg); + + } else { + dev_dbg(mdev_state->vdev.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; +} + +static int mbochs_reset(struct mdev_state *mdev_state) +{ + 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; +} + +static int mbochs_init_dev(struct vfio_device *vdev) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + struct mdev_device *mdev = to_mdev_device(vdev->dev); + struct mbochs_type *type = + container_of(mdev->type, struct mbochs_type, type); + int avail_mbytes = atomic_read(&mbochs_avail_mbytes); + int ret = -ENOMEM; + + do { + if (avail_mbytes < type->mbytes) + return -ENOSPC; + } while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes, + avail_mbytes - type->mbytes)); + + mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL); + if (!mdev_state->vconfig) + goto err_avail; + + mdev_state->memsize = type->mbytes * 1024 * 1024; + mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT; + mdev_state->pages = kcalloc(mdev_state->pagecount, + sizeof(struct page *), + GFP_KERNEL); + if (!mdev_state->pages) + goto err_vconfig; + + mutex_init(&mdev_state->ops_lock); + mdev_state->mdev = mdev; + INIT_LIST_HEAD(&mdev_state->dmabufs); + mdev_state->next_id = 1; + + mdev_state->type = type; + mdev_state->edid_regs.max_xres = type->max_x; + mdev_state->edid_regs.max_yres = type->max_y; + mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET; + mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob); + mbochs_create_config_space(mdev_state); + mbochs_reset(mdev_state); + + dev_info(vdev->dev, "%s: %s, %d MB, %ld pages\n", __func__, + type->type.pretty_name, type->mbytes, mdev_state->pagecount); + return 0; + +err_vconfig: + kfree(mdev_state->vconfig); +err_avail: + atomic_add(type->mbytes, &mbochs_avail_mbytes); + return ret; +} + +static int mbochs_probe(struct mdev_device *mdev) +{ + struct mdev_state *mdev_state; + int ret = -ENOMEM; + + mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev, + &mbochs_dev_ops); + if (IS_ERR(mdev_state)) + return PTR_ERR(mdev_state); + + ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev); + if (ret) + goto err_put_vdev; + dev_set_drvdata(&mdev->dev, mdev_state); + return 0; + +err_put_vdev: + vfio_put_device(&mdev_state->vdev); + return ret; +} + +static void mbochs_release_dev(struct vfio_device *vdev) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + + atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes); + kfree(mdev_state->pages); + kfree(mdev_state->vconfig); + vfio_free_device(vdev); +} + +static void mbochs_remove(struct mdev_device *mdev) +{ + struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev); + + vfio_unregister_group_dev(&mdev_state->vdev); + vfio_put_device(&mdev_state->vdev); +} + +static ssize_t mbochs_read(struct vfio_device *vdev, char __user *buf, + size_t count, loff_t *ppos) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + unsigned int done = 0; + int ret; + + while (count) { + size_t filled; + + if (count >= 4 && !(*ppos % 4)) { + u32 val; + + ret = mdev_access(mdev_state, (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_state, (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_state, (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; +} + +static ssize_t mbochs_write(struct vfio_device *vdev, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + 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_state, (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_state, (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_state, (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; +} + +static 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]; +} + +static 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; +} + +static 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 vm_fault_t 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, +}; + +static int mbochs_mmap(struct vfio_device *vdev, struct vm_area_struct *vma) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + + 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 vm_fault_t 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_sgtable(at->dev, sg, direction, 0)) + 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); + + dma_unmap_sgtable(at->dev, sg, direction, 0); + 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 struct dma_buf_ops mbochs_dmabuf_ops = { + .map_dma_buf = mbochs_map_dmabuf, + .unmap_dma_buf = mbochs_unmap_dmabuf, + .release = mbochs_release_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 = kcalloc(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_state->vdev.dev; + 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; +} + +static int mbochs_get_region_info(struct mdev_state *mdev_state, + struct vfio_region_info_ext *ext) +{ + struct vfio_region_info *region_info = &ext->base; + + if (region_info->index >= MBOCHS_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; + case MBOCHS_EDID_REGION_INDEX: + ext->base.argsz = sizeof(*ext); + ext->base.offset = MBOCHS_EDID_OFFSET; + ext->base.size = MBOCHS_EDID_SIZE; + ext->base.flags = (VFIO_REGION_INFO_FLAG_READ | + VFIO_REGION_INFO_FLAG_WRITE | + VFIO_REGION_INFO_FLAG_CAPS); + ext->base.cap_offset = offsetof(typeof(*ext), type); + ext->type.header.id = VFIO_REGION_INFO_CAP_TYPE; + ext->type.header.version = 1; + ext->type.header.next = 0; + ext->type.type = VFIO_REGION_TYPE_GFX; + ext->type.subtype = VFIO_REGION_SUBTYPE_GFX_EDID; + break; + default: + region_info->size = 0; + region_info->offset = 0; + region_info->flags = 0; + } + + return 0; +} + +static int mbochs_get_irq_info(struct vfio_irq_info *irq_info) +{ + irq_info->count = 0; + return 0; +} + +static int mbochs_get_device_info(struct vfio_device_info *dev_info) +{ + dev_info->flags = VFIO_DEVICE_FLAGS_PCI; + dev_info->num_regions = MBOCHS_NUM_REGIONS; + dev_info->num_irqs = VFIO_PCI_NUM_IRQS; + return 0; +} + +static int mbochs_query_gfx_plane(struct mdev_state *mdev_state, + struct vfio_device_gfx_plane_info *plane) +{ + 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(mdev_state->vdev.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; +} + +static int mbochs_get_gfx_dmabuf(struct mdev_state *mdev_state, u32 id) +{ + 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 vfio_device *vdev, unsigned int cmd, + unsigned long arg) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + int ret = 0; + unsigned long minsz, outsz; + + 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(&info); + if (ret) + return ret; + + if (copy_to_user((void __user *)arg, &info, minsz)) + return -EFAULT; + + return 0; + } + case VFIO_DEVICE_GET_REGION_INFO: + { + struct vfio_region_info_ext info; + + minsz = offsetofend(typeof(info), base.offset); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + outsz = info.base.argsz; + if (outsz < minsz) + return -EINVAL; + if (outsz > sizeof(info)) + return -EINVAL; + + ret = mbochs_get_region_info(mdev_state, &info); + if (ret) + return ret; + + if (copy_to_user((void __user *)arg, &info, outsz)) + 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 >= VFIO_PCI_NUM_IRQS)) + return -EINVAL; + + ret = mbochs_get_irq_info(&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_state, &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_state, dmabuf_id); + } + + case VFIO_DEVICE_SET_IRQS: + return -EINVAL; + + case VFIO_DEVICE_RESET: + return mbochs_reset(mdev_state); + } + return -ENOTTY; +} + +static void mbochs_close_device(struct vfio_device *vdev) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + 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); +} + +static ssize_t +memory_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct mdev_state *mdev_state = dev_get_drvdata(dev); + + 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, +}; + +static const struct attribute_group *mdev_dev_groups[] = { + &mdev_dev_group, + NULL, +}; + +static ssize_t mbochs_show_description(struct mdev_type *mtype, char *buf) +{ + struct mbochs_type *type = + container_of(mtype, struct mbochs_type, type); + + return sprintf(buf, "virtual display, %d MB video memory\n", + type ? type->mbytes : 0); +} + +static unsigned int mbochs_get_available(struct mdev_type *mtype) +{ + struct mbochs_type *type = + container_of(mtype, struct mbochs_type, type); + + return atomic_read(&mbochs_avail_mbytes) / type->mbytes; +} + +static const struct vfio_device_ops mbochs_dev_ops = { + .close_device = mbochs_close_device, + .init = mbochs_init_dev, + .release = mbochs_release_dev, + .read = mbochs_read, + .write = mbochs_write, + .ioctl = mbochs_ioctl, + .mmap = mbochs_mmap, +}; + +static struct mdev_driver mbochs_driver = { + .device_api = VFIO_DEVICE_API_PCI_STRING, + .driver = { + .name = "mbochs", + .owner = THIS_MODULE, + .mod_name = KBUILD_MODNAME, + .dev_groups = mdev_dev_groups, + }, + .probe = mbochs_probe, + .remove = mbochs_remove, + .get_available = mbochs_get_available, + .show_description = mbochs_show_description, +}; + +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; + + atomic_set(&mbochs_avail_mbytes, max_mbytes); + + ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK + 1, 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 + 1); + pr_info("%s: major %d\n", __func__, MAJOR(mbochs_devt)); + + ret = mdev_register_driver(&mbochs_driver); + if (ret) + goto err_cdev; + + 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 err_driver; + } + 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 err_class; + + ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver, + mbochs_mdev_types, + ARRAY_SIZE(mbochs_mdev_types)); + if (ret) + goto err_device; + + return 0; + +err_device: + device_unregister(&mbochs_dev); +err_class: + class_destroy(mbochs_class); +err_driver: + mdev_unregister_driver(&mbochs_driver); +err_cdev: + cdev_del(&mbochs_cdev); + unregister_chrdev_region(mbochs_devt, MINORMASK + 1); + return ret; +} + +static void __exit mbochs_dev_exit(void) +{ + mbochs_dev.bus = NULL; + mdev_unregister_parent(&mbochs_parent); + + device_unregister(&mbochs_dev); + mdev_unregister_driver(&mbochs_driver); + cdev_del(&mbochs_cdev); + unregister_chrdev_region(mbochs_devt, MINORMASK + 1); + class_destroy(mbochs_class); + mbochs_class = NULL; +} + +MODULE_IMPORT_NS(DMA_BUF); +module_init(mbochs_dev_init) +module_exit(mbochs_dev_exit) |