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#include <linux/anon_inodes.h>
#include <linux/file.h>
#include <linux/fs.h>
#include "private_data.h"
#include "surface.h"
long surface_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
return -1;
}
ssize_t surface_read(struct file *filp, char __user *buf, size_t count,
loff_t *offset)
{
return -1;
}
loff_t surface_llseek(struct file *filp, loff_t offset, int origin)
{
return -1;
}
struct file_operations surface_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = surface_ioctl,
.compat_ioctl = surface_ioctl,
.llseek = surface_llseek,
.read = surface_read
};
int verify_params(struct doomdev_ioctl_create_surface *params)
{
if (params->width < 64) {
printk(KERN_DEBUG "Surface width too small\n");
return -EINVAL;
}
if (params->width > 2048) {
printk(KERN_DEBUG "Surface width too large\n");
return -EOVERFLOW;
}
if (params->width % 64 != 0) {
printk(KERN_DEBUG "Surface width not a multiple of 64\n");
return -EINVAL;
}
if (params->height < 1) {
printk(KERN_DEBUG "Surface height too small\n");
return -EINVAL;
}
if (params->height > 2048) {
printk(KERN_DEBUG "Surface height too large\n");
return -EOVERFLOW;
}
return 0;
}
int new_surface(struct doomdev_ioctl_create_surface *params)
{
int err;
int fd;
struct fd fd_s;
err = verify_params(params);
if (err < 0) {
return err;
}
fd = anon_inode_getfd("doom_surface", &surface_fops, NULL, 0);
fd_s = fdget(fd);
if (fd_s.file->f_op != &surface_fops) {
printk(KERN_DEBUG "fdget failed\n");
return -ENOENT;
}
fd_s.file->f_mode |= FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE;
return fd;
}
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