[PATCH] 2.5.22: new xpram driver.

seems someone else was faster fixing the hardsects problem in the xpram
driver.  We continued with my new version of the xpram driver.  Arnd
Bergmann found some bugs and added support for the driverfs.

drivers/s390/block/xpram.h

-
-/*
- * xpram.h -- definitions for the char module
- *
- *********/
-
-
-#include <linux/ioctl.h>
-#include <asm/atomic.h>
-#include <linux/major.h>
-
-/* version dependencies have been confined to a separate file */
-
-/*
- * Macros to help debugging
- */
-
-#define XPRAM_NAME "xpram"  /* name of device/module */
-#define XPRAM_DEVICE_NAME_PREFIX "slram" /* Prefix device name for major 35 */
-#define XPRAM_DEVS 1        /* one partition */
-#define XPRAM_RAHEAD 8      /* no real read ahead */
-#define XPRAM_PGSIZE 4096   /* page size of (expanded) mememory pages
-                             * according to S/390 architecture
-                             */
-#define XPRAM_BLKSIZE XPRAM_PGSIZE  /* must be equalt to page size ! */
-#define XPRAM_HARDSECT XPRAM_PGSIZE /* FIXME -- we have to deal with both
-                                     * this hard sect size and in some cases
-                                     * hard coded 512 bytes which I call
-                                     * soft sects:
-                                     */
-#define XPRAM_SOFTSECT 512
-#define XPRAM_MAX_DEVS 32   /* maximal number of devices (partitions) */
-#define XPRAM_MAX_DEVS1 33  /* maximal number of devices (partitions) +1 */
-
-/* The following macros depend on the sizes above */
-
-#define XPRAM_KB_IN_PG 4                     /* 4 kBs per page */
-#define XPRAM_KB_IN_PG_ORDER 2               /* 2^? kBs per page */
-
-/* Eventhough XPRAM_HARDSECT is set to 4k some data structures use hard
- * coded 512 byte sa sector size
- */
-#define XPRAM_SEC2KB(x) ((x >> 1) + (x & 1)) /* modifier used to compute size 
-                                                in kB from number of sectors */
-#define XPRAM_SEC_IN_PG 8                    /* 8 sectors per page */
-#define XPRAM_SEC_IN_PG_ORDER 3              /* 2^? sectors per page */
-
-#define XPRAM_UNUSED 40                     /* unused space between devices, 
-                                             * in kB, i.e.
-                                             * must be a multiple of 4
-                                             */
-/*
- * The xpram device is removable: if it is left closed for more than
- * half a minute, it is removed. Thus use a usage count and a
- * kernel timer
- */
-
-typedef struct Xpram_Dev {
-   int            size;   /* size in KB not in Byte - RB - */
-   atomic_t       usage;
-   char *         device_name;   /* device name prefix in devfs */
-   devfs_handle_t devfs_entry;   /* handle needed to unregister dev from devfs */
-   u8 *data;
-}              Xpram_Dev;
-
-/* 2.2: void xpram_setup (char *, int *); */
-/* begin 2.3 */
-int xpram_setup (char *);
-/* end 2.3 */
-int xpram_init(void);