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/* -*- C -*-
* scullp.h -- definitions for the scullp char module
*
* Copyright (C) 2001 Alessandro Rubini and Jonathan Corbet
* Copyright (C) 2001 O'Reilly & Associates
*
* The source code in this file can be freely used, adapted,
* and redistributed in source or binary form, so long as an
* acknowledgment appears in derived source files. The citation
* should list that the code comes from the book "Linux Device
* Drivers" by Alessandro Rubini and Jonathan Corbet, published
* by O'Reilly & Associates. No warranty is attached;
* we cannot take responsibility for errors or fitness for use.
*/
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/semaphore.h>
/*
* Macros to help debugging
*/
#undef PDEBUG /* undef it, just in case */
#ifdef SCULLP_DEBUG
# ifdef __KERNEL__
/* This one if debugging is on, and kernel space */
# define PDEBUG(fmt, args...) printk( KERN_DEBUG "scullp: " fmt, ## args)
# else
/* This one for user space */
# define PDEBUG(fmt, args...) fprintf(stderr, fmt, ## args)
# endif
#else
# define PDEBUG(fmt, args...) /* not debugging: nothing */
#endif
#undef PDEBUGG
#define PDEBUGG(fmt, args...) /* nothing: it's a placeholder */
#define SCULLP_MAJOR 0 /* dynamic major by default */
#define SCULLP_DEVS 4 /* scullp0 through scullp3 */
/*
* The bare device is a variable-length region of memory.
* Use a linked list of indirect blocks.
*
* "scullp_dev->data" points to an array of pointers, each
* pointer refers to a memory page.
*
* The array (quantum-set) is SCULLP_QSET long.
*/
#define SCULLP_ORDER 0 /* one page at a time */
#define SCULLP_QSET 500
struct scullp_dev {
void **data;
struct scullp_dev *next; /* next listitem */
int vmas; /* active mappings */
int order; /* the current allocation order */
int qset; /* the current array size */
size_t size; /* 32-bit will suffice */
struct semaphore sem; /* Mutual exclusion */
struct cdev cdev;
};
extern struct scullp_dev *scullp_devices;
extern struct file_operations scullp_fops;
/*
* The different configurable parameters
*/
extern int scullp_major; /* main.c */
extern int scullp_devs;
extern int scullp_order;
extern int scullp_qset;
/*
* Prototypes for shared functions
*/
int scullp_trim(struct scullp_dev *dev);
struct scullp_dev *scullp_follow(struct scullp_dev *dev, int n);
#ifdef SCULLP_DEBUG
# define SCULLP_USE_PROC
#endif
/*
* Ioctl definitions
*/
/* Use 'K' as magic number */
#define SCULLP_IOC_MAGIC 'K'
#define SCULLP_IOCRESET _IO(SCULLP_IOC_MAGIC, 0)
/*
* S means "Set" through a ptr,
* T means "Tell" directly
* G means "Get" (to a pointed var)
* Q means "Query", response is on the return value
* X means "eXchange": G and S atomically
* H means "sHift": T and Q atomically
*/
#define SCULLP_IOCSORDER _IOW(SCULLP_IOC_MAGIC, 1, int)
#define SCULLP_IOCTORDER _IO(SCULLP_IOC_MAGIC, 2)
#define SCULLP_IOCGORDER _IOR(SCULLP_IOC_MAGIC, 3, int)
#define SCULLP_IOCQORDER _IO(SCULLP_IOC_MAGIC, 4)
#define SCULLP_IOCXORDER _IOWR(SCULLP_IOC_MAGIC, 5, int)
#define SCULLP_IOCHORDER _IO(SCULLP_IOC_MAGIC, 6)
#define SCULLP_IOCSQSET _IOW(SCULLP_IOC_MAGIC, 7, int)
#define SCULLP_IOCTQSET _IO(SCULLP_IOC_MAGIC, 8)
#define SCULLP_IOCGQSET _IOR(SCULLP_IOC_MAGIC, 9, int)
#define SCULLP_IOCQQSET _IO(SCULLP_IOC_MAGIC, 10)
#define SCULLP_IOCXQSET _IOWR(SCULLP_IOC_MAGIC,11, int)
#define SCULLP_IOCHQSET _IO(SCULLP_IOC_MAGIC, 12)
#define SCULLP_IOC_MAXNR 12
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