diff options
Diffstat (limited to 'samples/vfio-mdev/mdpy.c')
| -rw-r--r-- | samples/vfio-mdev/mdpy.c | 764 |
1 files changed, 764 insertions, 0 deletions
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c new file mode 100644 index 0000000000..064e1c0a7a --- /dev/null +++ b/samples/vfio-mdev/mdpy.c @@ -0,0 +1,764 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Mediated virtual PCI display host device driver + * + * See mdpy-defs.h for device specs + * + * (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 <drm/drm_fourcc.h> +#include "mdpy-defs.h" + +#define MDPY_NAME "mdpy" +#define MDPY_CLASS_NAME "mdpy" + +#define MDPY_CONFIG_SPACE_SIZE 0xff +#define MDPY_MEMORY_BAR_OFFSET PAGE_SIZE +#define MDPY_DISPLAY_REGION 16 + +#define STORE_LE16(addr, val) (*(u16 *)addr = val) +#define STORE_LE32(addr, val) (*(u32 *)addr = val) + + +MODULE_LICENSE("GPL v2"); + +#define MDPY_TYPE_1 "vga" +#define MDPY_TYPE_2 "xga" +#define MDPY_TYPE_3 "hd" + +static struct mdpy_type { + struct mdev_type type; + u32 format; + u32 bytepp; + u32 width; + u32 height; +} mdpy_types[] = { + { + .type.sysfs_name = MDPY_TYPE_1, + .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_1, + .format = DRM_FORMAT_XRGB8888, + .bytepp = 4, + .width = 640, + .height = 480, + }, { + .type.sysfs_name = MDPY_TYPE_2, + .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_2, + .format = DRM_FORMAT_XRGB8888, + .bytepp = 4, + .width = 1024, + .height = 768, + }, { + .type.sysfs_name = MDPY_TYPE_3, + .type.pretty_name = MDPY_CLASS_NAME "-" MDPY_TYPE_3, + .format = DRM_FORMAT_XRGB8888, + .bytepp = 4, + .width = 1920, + .height = 1080, + }, +}; + +static struct mdev_type *mdpy_mdev_types[] = { + &mdpy_types[0].type, + &mdpy_types[1].type, + &mdpy_types[2].type, +}; + +static dev_t mdpy_devt; +static struct class *mdpy_class; +static struct cdev mdpy_cdev; +static struct device mdpy_dev; +static struct mdev_parent mdpy_parent; +static const struct vfio_device_ops mdpy_dev_ops; + +/* State of each mdev device */ +struct mdev_state { + struct vfio_device vdev; + u8 *vconfig; + u32 bar_mask; + struct mutex ops_lock; + struct mdev_device *mdev; + struct vfio_device_info dev_info; + + const struct mdpy_type *type; + u32 memsize; + void *memblk; +}; + +static void mdpy_create_config_space(struct mdev_state *mdev_state) +{ + STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID], + MDPY_PCI_VENDOR_ID); + STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID], + MDPY_PCI_DEVICE_ID); + STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID], + MDPY_PCI_SUBVENDOR_ID); + STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID], + MDPY_PCI_SUBDEVICE_ID); + + STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND], + PCI_COMMAND_IO | PCI_COMMAND_MEMORY); + STORE_LE16((u16 *) &mdev_state->vconfig[PCI_STATUS], + PCI_STATUS_CAP_LIST); + 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 = ~(mdev_state->memsize) + 1; + + /* vendor specific capability for the config registers */ + mdev_state->vconfig[PCI_CAPABILITY_LIST] = MDPY_VENDORCAP_OFFSET; + mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 0] = 0x09; /* vendor cap */ + mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 1] = 0x00; /* next ptr */ + mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 2] = MDPY_VENDORCAP_SIZE; + STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_FORMAT_OFFSET], + mdev_state->type->format); + STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_WIDTH_OFFSET], + mdev_state->type->width); + STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_HEIGHT_OFFSET], + mdev_state->type->height); +} + +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); + u32 cfg_addr; + + switch (offset) { + case PCI_BASE_ADDRESS_0: + cfg_addr = *(u32 *)buf; + + if (cfg_addr == 0xffffffff) { + cfg_addr = (cfg_addr & mdev_state->bar_mask); + } else { + cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK; + if (cfg_addr) + dev_info(dev, "BAR0 @ 0x%x\n", cfg_addr); + } + + cfg_addr |= (mdev_state->vconfig[offset] & + ~PCI_BASE_ADDRESS_MEM_MASK); + STORE_LE32(&mdev_state->vconfig[offset], cfg_addr); + break; + } +} + +static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf, + size_t count, loff_t pos, bool is_write) +{ + int ret = 0; + + mutex_lock(&mdev_state->ops_lock); + + if (pos < MDPY_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 >= MDPY_MEMORY_BAR_OFFSET) && + (pos + count <= + MDPY_MEMORY_BAR_OFFSET + mdev_state->memsize)) { + pos -= MDPY_MEMORY_BAR_OFFSET; + if (is_write) + memcpy(mdev_state->memblk, buf, count); + else + memcpy(buf, mdev_state->memblk, count); + + } else { + dev_info(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 mdpy_reset(struct mdev_state *mdev_state) +{ + u32 stride, i; + + /* initialize with gray gradient */ + stride = mdev_state->type->width * mdev_state->type->bytepp; + for (i = 0; i < mdev_state->type->height; i++) + memset(mdev_state->memblk + i * stride, + i * 255 / mdev_state->type->height, + stride); + return 0; +} + +static int mdpy_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); + const struct mdpy_type *type = + container_of(mdev->type, struct mdpy_type, type); + u32 fbsize; + int ret = -ENOMEM; + + mdev_state->vconfig = kzalloc(MDPY_CONFIG_SPACE_SIZE, GFP_KERNEL); + if (!mdev_state->vconfig) + return ret; + + fbsize = roundup_pow_of_two(type->width * type->height * type->bytepp); + + mdev_state->memblk = vmalloc_user(fbsize); + if (!mdev_state->memblk) + goto out_vconfig; + + mutex_init(&mdev_state->ops_lock); + mdev_state->mdev = mdev; + mdev_state->type = type; + mdev_state->memsize = fbsize; + mdpy_create_config_space(mdev_state); + mdpy_reset(mdev_state); + + dev_info(vdev->dev, "%s: %s (%dx%d)\n", __func__, type->type.pretty_name, + type->width, type->height); + return 0; + +out_vconfig: + kfree(mdev_state->vconfig); + return ret; +} + +static int mdpy_probe(struct mdev_device *mdev) +{ + struct mdev_state *mdev_state; + int ret; + + mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev, + &mdpy_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 mdpy_release_dev(struct vfio_device *vdev) +{ + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + + vfree(mdev_state->memblk); + kfree(mdev_state->vconfig); +} + +static void mdpy_remove(struct mdev_device *mdev) +{ + struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev); + + dev_info(&mdev->dev, "%s\n", __func__); + + vfio_unregister_group_dev(&mdev_state->vdev); + vfio_put_device(&mdev_state->vdev); +} + +static ssize_t mdpy_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 mdpy_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 int mdpy_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 != MDPY_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; + + return remap_vmalloc_range(vma, mdev_state->memblk, 0); +} + +static int mdpy_get_region_info(struct mdev_state *mdev_state, + struct vfio_region_info *region_info, + u16 *cap_type_id, void **cap_type) +{ + if (region_info->index >= VFIO_PCI_NUM_REGIONS && + region_info->index != MDPY_DISPLAY_REGION) + return -EINVAL; + + switch (region_info->index) { + case VFIO_PCI_CONFIG_REGION_INDEX: + region_info->offset = 0; + region_info->size = MDPY_CONFIG_SPACE_SIZE; + region_info->flags = (VFIO_REGION_INFO_FLAG_READ | + VFIO_REGION_INFO_FLAG_WRITE); + break; + case VFIO_PCI_BAR0_REGION_INDEX: + case MDPY_DISPLAY_REGION: + region_info->offset = MDPY_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; + default: + region_info->size = 0; + region_info->offset = 0; + region_info->flags = 0; + } + + return 0; +} + +static int mdpy_get_irq_info(struct vfio_irq_info *irq_info) +{ + irq_info->count = 0; + return 0; +} + +static int mdpy_get_device_info(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; +} + +static int mdpy_query_gfx_plane(struct mdev_state *mdev_state, + struct vfio_device_gfx_plane_info *plane) +{ + if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) { + if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE | + VFIO_GFX_PLANE_TYPE_REGION)) + return 0; + return -EINVAL; + } + + if (plane->flags != VFIO_GFX_PLANE_TYPE_REGION) + return -EINVAL; + + plane->drm_format = mdev_state->type->format; + plane->width = mdev_state->type->width; + plane->height = mdev_state->type->height; + plane->stride = (mdev_state->type->width * + mdev_state->type->bytepp); + plane->size = mdev_state->memsize; + plane->region_index = MDPY_DISPLAY_REGION; + + /* unused */ + plane->drm_format_mod = 0; + plane->x_pos = 0; + plane->y_pos = 0; + plane->x_hot = 0; + plane->y_hot = 0; + + return 0; +} + +static long mdpy_ioctl(struct vfio_device *vdev, unsigned int cmd, + unsigned long arg) +{ + int ret = 0; + unsigned long minsz; + struct mdev_state *mdev_state = + container_of(vdev, struct mdev_state, vdev); + + 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 = mdpy_get_device_info(&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 = mdpy_get_region_info(mdev_state, &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 = mdpy_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 = mdpy_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_SET_IRQS: + return -EINVAL; + + case VFIO_DEVICE_RESET: + return mdpy_reset(mdev_state); + } + return -ENOTTY; +} + +static ssize_t +resolution_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct mdev_state *mdev_state = dev_get_drvdata(dev); + + return sprintf(buf, "%dx%d\n", + mdev_state->type->width, + mdev_state->type->height); +} +static DEVICE_ATTR_RO(resolution); + +static struct attribute *mdev_dev_attrs[] = { + &dev_attr_resolution.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 mdpy_show_description(struct mdev_type *mtype, char *buf) +{ + struct mdpy_type *type = container_of(mtype, struct mdpy_type, type); + + return sprintf(buf, "virtual display, %dx%d framebuffer\n", + type->width, type->height); +} + +static const struct vfio_device_ops mdpy_dev_ops = { + .init = mdpy_init_dev, + .release = mdpy_release_dev, + .read = mdpy_read, + .write = mdpy_write, + .ioctl = mdpy_ioctl, + .mmap = mdpy_mmap, + .bind_iommufd = vfio_iommufd_emulated_bind, + .unbind_iommufd = vfio_iommufd_emulated_unbind, + .attach_ioas = vfio_iommufd_emulated_attach_ioas, + .detach_ioas = vfio_iommufd_emulated_detach_ioas, +}; + +static struct mdev_driver mdpy_driver = { + .device_api = VFIO_DEVICE_API_PCI_STRING, + .max_instances = 4, + .driver = { + .name = "mdpy", + .owner = THIS_MODULE, + .mod_name = KBUILD_MODNAME, + .dev_groups = mdev_dev_groups, + }, + .probe = mdpy_probe, + .remove = mdpy_remove, + .show_description = mdpy_show_description, +}; + +static const struct file_operations vd_fops = { + .owner = THIS_MODULE, +}; + +static void mdpy_device_release(struct device *dev) +{ + /* nothing */ +} + +static int __init mdpy_dev_init(void) +{ + int ret = 0; + + ret = alloc_chrdev_region(&mdpy_devt, 0, MINORMASK + 1, MDPY_NAME); + if (ret < 0) { + pr_err("Error: failed to register mdpy_dev, err: %d\n", ret); + return ret; + } + cdev_init(&mdpy_cdev, &vd_fops); + cdev_add(&mdpy_cdev, mdpy_devt, MINORMASK + 1); + pr_info("%s: major %d\n", __func__, MAJOR(mdpy_devt)); + + ret = mdev_register_driver(&mdpy_driver); + if (ret) + goto err_cdev; + + mdpy_class = class_create(MDPY_CLASS_NAME); + if (IS_ERR(mdpy_class)) { + pr_err("Error: failed to register mdpy_dev class\n"); + ret = PTR_ERR(mdpy_class); + goto err_driver; + } + mdpy_dev.class = mdpy_class; + mdpy_dev.release = mdpy_device_release; + dev_set_name(&mdpy_dev, "%s", MDPY_NAME); + + ret = device_register(&mdpy_dev); + if (ret) + goto err_put; + + ret = mdev_register_parent(&mdpy_parent, &mdpy_dev, &mdpy_driver, + mdpy_mdev_types, + ARRAY_SIZE(mdpy_mdev_types)); + if (ret) + goto err_device; + + return 0; + +err_device: + device_del(&mdpy_dev); +err_put: + put_device(&mdpy_dev); + class_destroy(mdpy_class); +err_driver: + mdev_unregister_driver(&mdpy_driver); +err_cdev: + cdev_del(&mdpy_cdev); + unregister_chrdev_region(mdpy_devt, MINORMASK + 1); + return ret; +} + +static void __exit mdpy_dev_exit(void) +{ + mdpy_dev.bus = NULL; + mdev_unregister_parent(&mdpy_parent); + + device_unregister(&mdpy_dev); + mdev_unregister_driver(&mdpy_driver); + cdev_del(&mdpy_cdev); + unregister_chrdev_region(mdpy_devt, MINORMASK + 1); + class_destroy(mdpy_class); + mdpy_class = NULL; +} + +module_param_named(count, mdpy_driver.max_instances, int, 0444); +MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices"); + +module_init(mdpy_dev_init) +module_exit(mdpy_dev_exit) |