123 lines
3.5 KiB
C
123 lines
3.5 KiB
C
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/* -*- C -*-
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* scullv.h -- definitions for the scullv char module
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*
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* Copyright (C) 2001 Alessandro Rubini and Jonathan Corbet
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* Copyright (C) 2001 O'Reilly & Associates
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*
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* The source code in this file can be freely used, adapted,
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* and redistributed in source or binary form, so long as an
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* acknowledgment appears in derived source files. The citation
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* should list that the code comes from the book "Linux Device
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* Drivers" by Alessandro Rubini and Jonathan Corbet, published
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* by O'Reilly & Associates. No warranty is attached;
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* we cannot take responsibility for errors or fitness for use.
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*/
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#include <linux/ioctl.h>
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#include <linux/cdev.h>
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/*
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* Macros to help debugging
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*/
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#undef PDEBUG /* undef it, just in case */
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#ifdef SCULLV_DEBUG
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# ifdef __KERNEL__
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/* This one if debugging is on, and kernel space */
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# define PDEBUG(fmt, args...) printk( KERN_DEBUG "scullv: " fmt, ## args)
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# else
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/* This one for user space */
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# define PDEBUG(fmt, args...) fprintf(stderr, fmt, ## args)
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# endif
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#else
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# define PDEBUG(fmt, args...) /* not debugging: nothing */
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#endif
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#undef PDEBUGG
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#define PDEBUGG(fmt, args...) /* nothing: it's a placeholder */
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#define SCULLV_MAJOR 0 /* dynamic major by default */
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#define SCULLV_DEVS 4 /* scullv0 through scullv3 */
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/*
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* The bare device is a variable-length region of memory.
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* Use a linked list of indirect blocks.
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*
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* "scullv_dev->data" points to an array of pointers, each
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* pointer refers to a memory page.
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*
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* The array (quantum-set) is SCULLV_QSET long.
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*/
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#define SCULLV_ORDER 4 /* 16 pages at a time */
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#define SCULLV_QSET 500
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struct scullv_dev {
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void **data;
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struct scullv_dev *next; /* next listitem */
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int vmas; /* active mappings */
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int order; /* the current allocation order */
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int qset; /* the current array size */
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size_t size; /* 32-bit will suffice */
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struct semaphore sem; /* Mutual exclusion */
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struct cdev cdev;
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};
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extern struct scullv_dev *scullv_devices;
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extern struct file_operations scullv_fops;
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/*
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* The different configurable parameters
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*/
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extern int scullv_major; /* main.c */
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extern int scullv_devs;
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extern int scullv_order;
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extern int scullv_qset;
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/*
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* Prototypes for shared functions
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*/
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int scullv_trim(struct scullv_dev *dev);
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struct scullv_dev *scullv_follow(struct scullv_dev *dev, int n);
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#ifdef SCULLV_DEBUG
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# define SCULLV_USE_PROC
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#endif
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/*
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* Ioctl definitions
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*/
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/* Use 'K' as magic number */
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#define SCULLV_IOC_MAGIC 'K'
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#define SCULLV_IOCRESET _IO(SCULLV_IOC_MAGIC, 0)
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/*
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* S means "Set" through a ptr,
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* T means "Tell" directly
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* G means "Get" (to a pointed var)
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* Q means "Query", response is on the return value
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* X means "eXchange": G and S atomically
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* H means "sHift": T and Q atomically
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*/
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#define SCULLV_IOCSORDER _IOW(SCULLV_IOC_MAGIC, 1, int)
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#define SCULLV_IOCTORDER _IO(SCULLV_IOC_MAGIC, 2)
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#define SCULLV_IOCGORDER _IOR(SCULLV_IOC_MAGIC, 3, int)
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#define SCULLV_IOCQORDER _IO(SCULLV_IOC_MAGIC, 4)
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#define SCULLV_IOCXORDER _IOWR(SCULLV_IOC_MAGIC, 5, int)
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#define SCULLV_IOCHORDER _IO(SCULLV_IOC_MAGIC, 6)
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#define SCULLV_IOCSQSET _IOW(SCULLV_IOC_MAGIC, 7, int)
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#define SCULLV_IOCTQSET _IO(SCULLV_IOC_MAGIC, 8)
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#define SCULLV_IOCGQSET _IOR(SCULLV_IOC_MAGIC, 9, int)
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#define SCULLV_IOCQQSET _IO(SCULLV_IOC_MAGIC, 10)
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#define SCULLV_IOCXQSET _IOWR(SCULLV_IOC_MAGIC,11, int)
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#define SCULLV_IOCHQSET _IO(SCULLV_IOC_MAGIC, 12)
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#define SCULLV_IOC_MAXNR 12
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