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Diffstat (limited to 'scullc/scullc.h')
| -rw-r--r-- | scullc/scullc.h | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/scullc/scullc.h b/scullc/scullc.h new file mode 100644 index 0000000..86d5090 --- /dev/null +++ b/scullc/scullc.h @@ -0,0 +1,122 @@ +/* -*- C -*- + * scullc.h -- definitions for the scullc 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> + +/* + * Macros to help debugging + */ + +#undef PDEBUG /* undef it, just in case */ +#ifdef SCULLC_DEBUG +# ifdef __KERNEL__ + /* This one if debugging is on, and kernel space */ +# define PDEBUG(fmt, args...) printk( KERN_DEBUG "scullc: " 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 SCULLC_MAJOR 0 /* dynamic major by default */ + +#define SCULLC_DEVS 4 /* scullc0 through scullc3 */ + +/* + * The bare device is a variable-length region of memory. + * Use a linked list of indirect blocks. + * + * "scullc_dev->data" points to an array of pointers, each + * pointer refers to a memory page. + * + * The array (quantum-set) is SCULLC_QSET long. + */ +#define SCULLC_QUANTUM 4000 /* use a quantum size like scull */ +#define SCULLC_QSET 500 + +struct scullc_dev { + void **data; + struct scullc_dev *next; /* next listitem */ + int vmas; /* active mappings */ + int quantum; /* the current allocation size */ + int qset; /* the current array size */ + size_t size; /* 32-bit will suffice */ + struct semaphore sem; /* Mutual exclusion */ + struct cdev cdev; +}; + +extern struct scullc_dev *scullc_devices; + +extern struct file_operations scullc_fops; + +/* + * The different configurable parameters + */ +extern int scullc_major; /* main.c */ +extern int scullc_devs; +extern int scullc_order; +extern int scullc_qset; + +/* + * Prototypes for shared functions + */ +int scullc_trim(struct scullc_dev *dev); +struct scullc_dev *scullc_follow(struct scullc_dev *dev, int n); + + +#ifdef SCULLC_DEBUG +# define SCULLC_USE_PROC +#endif + +/* + * Ioctl definitions + */ + +/* Use 'K' as magic number */ +#define SCULLC_IOC_MAGIC 'K' + +#define SCULLC_IOCRESET _IO(SCULLC_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 SCULLC_IOCSQUANTUM _IOW(SCULLC_IOC_MAGIC, 1, int) +#define SCULLC_IOCTQUANTUM _IO(SCULLC_IOC_MAGIC, 2) +#define SCULLC_IOCGQUANTUM _IOR(SCULLC_IOC_MAGIC, 3, int) +#define SCULLC_IOCQQUANTUM _IO(SCULLC_IOC_MAGIC, 4) +#define SCULLC_IOCXQUANTUM _IOWR(SCULLC_IOC_MAGIC, 5, int) +#define SCULLC_IOCHQUANTUM _IO(SCULLC_IOC_MAGIC, 6) +#define SCULLC_IOCSQSET _IOW(SCULLC_IOC_MAGIC, 7, int) +#define SCULLC_IOCTQSET _IO(SCULLC_IOC_MAGIC, 8) +#define SCULLC_IOCGQSET _IOR(SCULLC_IOC_MAGIC, 9, int) +#define SCULLC_IOCQQSET _IO(SCULLC_IOC_MAGIC, 10) +#define SCULLC_IOCXQSET _IOWR(SCULLC_IOC_MAGIC,11, int) +#define SCULLC_IOCHQSET _IO(SCULLC_IOC_MAGIC, 12) + +#define SCULLC_IOC_MAXNR 12 + + + |