linux/drivers/video/fbdev/core/fb_chrdev.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/compat.h>
#include <linux/console.h>
#include <linux/fb.h>
#include <linux/fbcon.h>
#include <linux/major.h>

#include "fb_internal.h"

/*
 * We hold a reference to the fb_info in file->private_data,
 * but if the current registered fb has changed, we don't
 * actually want to use it.
 *
 * So look up the fb_info using the inode minor number,
 * and just verify it against the reference we have.
 */
static struct fb_info *file_fb_info(struct file *file)
{ … }

static ssize_t fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{ … }

static ssize_t fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{ … }

static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
			unsigned long arg)
{ … }

static long fb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{ … }

#ifdef CONFIG_COMPAT
struct fb_fix_screeninfo32 { … };

struct fb_cmap32 { … };

static int fb_getput_cmap(struct fb_info *info, unsigned int cmd,
			  unsigned long arg)
{ … }

static int do_fscreeninfo_to_user(struct fb_fix_screeninfo *fix,
				  struct fb_fix_screeninfo32 __user *fix32)
{ … }

static int fb_get_fscreeninfo(struct fb_info *info, unsigned int cmd,
			      unsigned long arg)
{ … }

static long fb_compat_ioctl(struct file *file, unsigned int cmd,
			    unsigned long arg)
{ … }
#endif

static int fb_mmap(struct file *file, struct vm_area_struct *vma)
{ … }

static int fb_open(struct inode *inode, struct file *file)
__acquires(&info->lock)
__releases(&info->lock)
{ … }

static int fb_release(struct inode *inode, struct file *file)
__acquires(&info->lock)
__releases(&info->lock)
{ … }

#if defined(CONFIG_FB_PROVIDE_GET_FB_UNMAPPED_AREA) && !defined(CONFIG_MMU)
static unsigned long get_fb_unmapped_area(struct file *filp,
				   unsigned long addr, unsigned long len,
				   unsigned long pgoff, unsigned long flags)
{
	struct fb_info * const info = filp->private_data;
	unsigned long fb_size = PAGE_ALIGN(info->fix.smem_len);

	if (pgoff > fb_size || len > fb_size - pgoff)
		return -EINVAL;

	return (unsigned long)info->screen_base + pgoff;
}
#endif

static const struct file_operations fb_fops = …;

int fb_register_chrdev(void)
{ … }

void fb_unregister_chrdev(void)
{ … }