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698f99ed5e
linux/samples/vfio-mdev/mbochs.c
Dan Carpenter 698f99ed5e vfio/mdev: remove unnecessary NULL check in mbochs_create() 
Originally "type" could be NULL and these checks were required, but we
recently changed how "type" is assigned and that's no longer the case.
Now "type" points to an element in the middle of a non-NULL array.

Removing the checks does not affect runtime at all, but it makes the
code a little bit simpler to read.

Fixes: 3d3a360e57 ("vfio/mbochs: Use mdev_get_type_group_id()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <20210429095327.GY1981@kadam>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-05-04 09:56:02 -06:00

1481 lines
36 KiB
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// 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/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/cdev.h>
#include <linux/vfio.h>
#include <linux/iommu.h>
#include <linux/sysfs.h>
#include <linux/mdev.h>
#include <linux/pci.h>
#include <linux/dma-buf.h>
#include <linux/highmem.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_rect.h>
#include <drm/drm_modeset_lock.h>
#include <drm/drm_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 const struct mbochs_type {
const char *name;
u32 mbytes;
u32 max_x;
u32 max_y;
} mbochs_types[] = {
{
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
.mbytes = 4,
.max_x = 800,
.max_y = 600,
}, {
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
.mbytes = 16,
.max_x = 1920,
.max_y = 1440,
}, {
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
.mbytes = 64,
.max_x = 0,
.max_y = 0,
},
};
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 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 {
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_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);
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(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_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;
}
static int mbochs_create(struct mdev_device *mdev)
{
const struct mbochs_type *type =
&mbochs_types[mdev_get_type_group_id(mdev)];
struct device *dev = mdev_dev(mdev);
struct mdev_state *mdev_state;
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 = kcalloc(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__,
type->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;
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);
mbochs_used_mbytes += type->mbytes;
return 0;
err_mem:
kfree(mdev_state->vconfig);
kfree(mdev_state);
return -ENOMEM;
}
static 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;
}
static 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;
}
static 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;
}
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 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 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_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;
}
static int mbochs_get_region_info(struct mdev_device *mdev,
struct vfio_region_info_ext *ext)
{
struct vfio_region_info *region_info = &ext->base;
struct mdev_state *mdev_state;
mdev_state = mdev_get_drvdata(mdev);
if (!mdev_state)
return -EINVAL;
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 mdev_device *mdev,
struct vfio_irq_info *irq_info)
{
irq_info->count = 0;
return 0;
}
static 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 = MBOCHS_NUM_REGIONS;
dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
return 0;
}
static 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;
}
static 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, 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(mdev, &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, &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(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;
}
static int mbochs_open(struct mdev_device *mdev)
{
if (!try_module_get(THIS_MODULE))
return -ENODEV;
return 0;
}
static 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,
};
static const struct attribute_group *mdev_dev_groups[] = {
&mdev_dev_group,
NULL,
};
static ssize_t name_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
const struct mbochs_type *type =
&mbochs_types[mtype_get_type_group_id(mtype)];
return sprintf(buf, "%s\n", type->name);
}
static MDEV_TYPE_ATTR_RO(name);
static ssize_t description_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
const struct mbochs_type *type =
&mbochs_types[mtype_get_type_group_id(mtype)];
return sprintf(buf, "virtual display, %d MB video memory\n",
type ? type->mbytes : 0);
}
static MDEV_TYPE_ATTR_RO(description);
static ssize_t available_instances_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr,
char *buf)
{
const struct mbochs_type *type =
&mbochs_types[mtype_get_type_group_id(mtype)];
int count = (max_mbytes - mbochs_used_mbytes) / type->mbytes;
return sprintf(buf, "%d\n", count);
}
static MDEV_TYPE_ATTR_RO(available_instances);
static ssize_t device_api_show(struct mdev_type *mtype,
struct mdev_type_attribute *attr, char *buf)
{
return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
}
static 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 + 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));
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 + 1);
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 + 1);
class_destroy(mbochs_class);
mbochs_class = NULL;
}
module_init(mbochs_dev_init)
module_exit(mbochs_dev_exit)
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