[mirror_ubuntu-kernels.git] / drivers / s390 / block / xpram.c

/*
 * Xpram.c -- the S/390 expanded memory RAM-disk
 *           
 * significant parts of this code are based on
 * the sbull device driver presented in
 * A. Rubini: Linux Device Drivers
 *
 * Author of XPRAM specific coding: Reinhard Buendgen
 *                                  buendgen@de.ibm.com
 * Rewrite for 2.5: Martin Schwidefsky <schwidefsky@de.ibm.com>
 *
 * External interfaces:
 *   Interfaces to linux kernel
 *        xpram_setup: read kernel parameters
 *   Device specific file operations
 *        xpram_iotcl
 *        xpram_open
 *
 * "ad-hoc" partitioning:
 *    the expanded memory can be partitioned among several devices 
 *    (with different minors). The partitioning set up can be
 *    set by kernel or module parameters (int devs & int sizes[])
 *
 * Potential future improvements:
 *   generic hard disk support to replace ad-hoc partitioning
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/ctype.h>  /* isdigit, isxdigit */
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/blkpg.h>
#include <linux/hdreg.h>  /* HDIO_GETGEO */
#include <linux/sysdev.h>
#include <linux/bio.h>
#include <asm/uaccess.h>

#define XPRAM_NAME	"xpram"
#define XPRAM_DEVS	1	/* one partition */
#define XPRAM_MAX_DEVS	32	/* maximal number of devices (partitions) */

#define PRINT_DEBUG(x...)	printk(KERN_DEBUG XPRAM_NAME " debug:" x)
#define PRINT_INFO(x...)	printk(KERN_INFO XPRAM_NAME " info:" x)
#define PRINT_WARN(x...)	printk(KERN_WARNING XPRAM_NAME " warning:" x)
#define PRINT_ERR(x...)		printk(KERN_ERR XPRAM_NAME " error:" x)


typedef struct {
	unsigned int	size;		/* size of xpram segment in pages */
	unsigned int	offset;		/* start page of xpram segment */
} xpram_device_t;

static xpram_device_t xpram_devices[XPRAM_MAX_DEVS];
static unsigned int xpram_sizes[XPRAM_MAX_DEVS];
static struct gendisk *xpram_disks[XPRAM_MAX_DEVS];
static struct request_queue *xpram_queues[XPRAM_MAX_DEVS];
static unsigned int xpram_pages;
static int xpram_devs;

/*
 * Parameter parsing functions.
 */
static int __initdata devs = XPRAM_DEVS;
static char __initdata *sizes[XPRAM_MAX_DEVS];

module_param(devs, int, 0);
module_param_array(sizes, charp, NULL, 0);

MODULE_PARM_DESC(devs, "number of devices (\"partitions\"), " \
		 "the default is " __MODULE_STRING(XPRAM_DEVS) "\n");
MODULE_PARM_DESC(sizes, "list of device (partition) sizes " \
		 "the defaults are 0s \n" \
		 "All devices with size 0 equally partition the "
		 "remaining space on the expanded strorage not "
		 "claimed by explicit sizes\n");
MODULE_LICENSE("GPL");

/*
 * Copy expanded memory page (4kB) into main memory                  
 * Arguments                                                         
 *           page_addr:    address of target page                    
 *           xpage_index:  index of expandeded memory page           
 * Return value                                                      
 *           0:            if operation succeeds
 *           -EIO:         if pgin failed
 *           -ENXIO:       if xpram has vanished
 */
static int xpram_page_in (unsigned long page_addr, unsigned int xpage_index)
{
	int cc = 2;	/* return unused cc 2 if pgin traps */

	asm volatile(
		"	.insn	rre,0xb22e0000,%1,%2\n"  /* pgin %1,%2 */
		"0:	ipm	%0\n"
		"	srl	%0,28\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "+d" (cc) : "a" (__pa(page_addr)), "d" (xpage_index) : "cc");
	if (cc == 3)
		return -ENXIO;
	if (cc == 2)
		return -ENXIO;
	if (cc == 1)
		return -EIO;
	return 0;
}

/*
 * Copy a 4kB page of main memory to an expanded memory page          
 * Arguments                                                          
 *           page_addr:    address of source page                     
 *           xpage_index:  index of expandeded memory page            
 * Return value                                                       
 *           0:            if operation succeeds
 *           -EIO:         if pgout failed
 *           -ENXIO:       if xpram has vanished
 */
static long xpram_page_out (unsigned long page_addr, unsigned int xpage_index)
{
	int cc = 2;	/* return unused cc 2 if pgin traps */

	asm volatile(
		"	.insn	rre,0xb22f0000,%1,%2\n"  /* pgout %1,%2 */
		"0:	ipm	%0\n"
		"	srl	%0,28\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "+d" (cc) : "a" (__pa(page_addr)), "d" (xpage_index) : "cc");
	if (cc == 3)
		return -ENXIO;
	if (cc == 2)
		return -ENXIO;
	if (cc == 1)
		return -EIO;
	return 0;
}

/*
 * Check if xpram is available.
 */
static int __init xpram_present(void)
{
	unsigned long mem_page;
	int rc;

	mem_page = (unsigned long) __get_free_page(GFP_KERNEL);
	if (!mem_page)
		return -ENOMEM;
	rc = xpram_page_in(mem_page, 0);
	free_page(mem_page);
	return rc ? -ENXIO : 0;
}

/*
 * Return index of the last available xpram page.
 */
static unsigned long __init xpram_highest_page_index(void)
{
	unsigned int page_index, add_bit;
	unsigned long mem_page;

	mem_page = (unsigned long) __get_free_page(GFP_KERNEL);
	if (!mem_page)
		return 0;

	page_index = 0;
	add_bit = 1ULL << (sizeof(unsigned int)*8 - 1);
	while (add_bit > 0) {
		if (xpram_page_in(mem_page, page_index | add_bit) == 0)
			page_index |= add_bit;
		add_bit >>= 1;
	}

	free_page (mem_page);

	return page_index;
}

/*
 * Block device make request function.
 */
static int xpram_make_request(struct request_queue *q, struct bio *bio)
{
	xpram_device_t *xdev = bio->bi_bdev->bd_disk->private_data;
	struct bio_vec *bvec;
	unsigned int index;
	unsigned long page_addr;
	unsigned long bytes;
	int i;

	if ((bio->bi_sector & 7) != 0 || (bio->bi_size & 4095) != 0)
		/* Request is not page-aligned. */
		goto fail;
	if ((bio->bi_size >> 12) > xdev->size)
		/* Request size is no page-aligned. */
		goto fail;
	if ((bio->bi_sector >> 3) > 0xffffffffU - xdev->offset)
		goto fail;
	index = (bio->bi_sector >> 3) + xdev->offset;
	bio_for_each_segment(bvec, bio, i) {
		page_addr = (unsigned long)
			kmap(bvec->bv_page) + bvec->bv_offset;
		bytes = bvec->bv_len;
		if ((page_addr & 4095) != 0 || (bytes & 4095) != 0)
			/* More paranoia. */
			goto fail;
		while (bytes > 0) {
			if (bio_data_dir(bio) == READ) {
				if (xpram_page_in(page_addr, index) != 0)
					goto fail;
			} else {
				if (xpram_page_out(page_addr, index) != 0)
					goto fail;
			}
			page_addr += 4096;
			bytes -= 4096;
			index++;
		}
	}
	set_bit(BIO_UPTODATE, &bio->bi_flags);
	bio_endio(bio, 0);
	return 0;
fail:
	bio_io_error(bio);
	return 0;
}

static int xpram_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
	unsigned long size;

	/*
	 * get geometry: we have to fake one...  trim the size to a
	 * multiple of 64 (32k): tell we have 16 sectors, 4 heads,
	 * whatever cylinders. Tell also that data starts at sector. 4.
	 */
	size = (xpram_pages * 8) & ~0x3f;
	geo->cylinders = size >> 6;
	geo->heads = 4;
	geo->sectors = 16;
	geo->start = 4;
	return 0;
}

static struct block_device_operations xpram_devops =
{
	.owner	= THIS_MODULE,
	.getgeo	= xpram_getgeo,
};

/*
 * Setup xpram_sizes array.
 */
static int __init xpram_setup_sizes(unsigned long pages)
{
	unsigned long mem_needed;
	unsigned long mem_auto;
	unsigned long long size;
	int mem_auto_no;
	int i;

	/* Check number of devices. */
	if (devs <= 0 || devs > XPRAM_MAX_DEVS) {
		PRINT_ERR("invalid number %d of devices\n",devs);
		return -EINVAL;
	}
	xpram_devs = devs;

	/*
	 * Copy sizes array to xpram_sizes and align partition
	 * sizes to page boundary.
	 */
	mem_needed = 0;
	mem_auto_no = 0;
	for (i = 0; i < xpram_devs; i++) {
		if (sizes[i]) {
			size = simple_strtoull(sizes[i], &sizes[i], 0);
			switch (sizes[i][0]) {
			case 'g':
			case 'G':
				size <<= 20;
				break;
			case 'm':
			case 'M':
				size <<= 10;
			}
			xpram_sizes[i] = (size + 3) & -4UL;
		}
		if (xpram_sizes[i])
			mem_needed += xpram_sizes[i];
		else
			mem_auto_no++;
	}
	
	PRINT_INFO("  number of devices (partitions): %d \n", xpram_devs);
	for (i = 0; i < xpram_devs; i++) {
		if (xpram_sizes[i])
			PRINT_INFO("  size of partition %d: %u kB\n",
				   i, xpram_sizes[i]);
		else
			PRINT_INFO("  size of partition %d to be set "
				   "automatically\n",i);
	}
	PRINT_DEBUG("  memory needed (for sized partitions): %lu kB\n",
		    mem_needed);
	PRINT_DEBUG("  partitions to be sized automatically: %d\n",
		    mem_auto_no);

	if (mem_needed > pages * 4) {
		PRINT_ERR("Not enough expanded memory available\n");
		return -EINVAL;
	}

	/*
	 * partitioning:
	 * xpram_sizes[i] != 0; partition i has size xpram_sizes[i] kB
	 * else:             ; all partitions with zero xpram_sizes[i]
	 *                     partition equally the remaining space
	 */
	if (mem_auto_no) {
		mem_auto = ((pages - mem_needed / 4) / mem_auto_no) * 4;
		PRINT_INFO("  automatically determined "
			   "partition size: %lu kB\n", mem_auto);
		for (i = 0; i < xpram_devs; i++)
			if (xpram_sizes[i] == 0)
				xpram_sizes[i] = mem_auto;
	}
	return 0;
}

static int __init xpram_setup_blkdev(void)
{
	unsigned long offset;
	int i, rc = -ENOMEM;

	for (i = 0; i < xpram_devs; i++) {
		xpram_disks[i] = alloc_disk(1);
		if (!xpram_disks[i])
			goto out;
		xpram_queues[i] = blk_alloc_queue(GFP_KERNEL);
		if (!xpram_queues[i]) {
			put_disk(xpram_disks[i]);
			goto out;
		}
		blk_queue_make_request(xpram_queues[i], xpram_make_request);
		blk_queue_hardsect_size(xpram_queues[i], 4096);
	}

	/*
	 * Register xpram major.
	 */
	rc = register_blkdev(XPRAM_MAJOR, XPRAM_NAME);
	if (rc < 0)
		goto out;

	/*
	 * Setup device structures.
	 */
	offset = 0;
	for (i = 0; i < xpram_devs; i++) {
		struct gendisk *disk = xpram_disks[i];

		xpram_devices[i].size = xpram_sizes[i] / 4;
		xpram_devices[i].offset = offset;
		offset += xpram_devices[i].size;
		disk->major = XPRAM_MAJOR;
		disk->first_minor = i;
		disk->fops = &xpram_devops;
		disk->private_data = &xpram_devices[i];
		disk->queue = xpram_queues[i];
		sprintf(disk->disk_name, "slram%d", i);
		set_capacity(disk, xpram_sizes[i] << 1);
		add_disk(disk);
	}

	return 0;
out:
	while (i--) {
		blk_cleanup_queue(xpram_queues[i]);
		put_disk(xpram_disks[i]);
	}
	return rc;
}

/*
 * Finally, the init/exit functions.
 */
static void __exit xpram_exit(void)
{
	int i;
	for (i = 0; i < xpram_devs; i++) {
		del_gendisk(xpram_disks[i]);
		blk_cleanup_queue(xpram_queues[i]);
		put_disk(xpram_disks[i]);
	}
	unregister_blkdev(XPRAM_MAJOR, XPRAM_NAME);
}

static int __init xpram_init(void)
{
	int rc;

	/* Find out size of expanded memory. */
	if (xpram_present() != 0) {
		PRINT_WARN("No expanded memory available\n");
		return -ENODEV;
	}
	xpram_pages = xpram_highest_page_index() + 1;
	PRINT_INFO("  %u pages expanded memory found (%lu KB).\n",
		   xpram_pages, (unsigned long) xpram_pages*4);
	rc = xpram_setup_sizes(xpram_pages);
	if (rc)
		return rc;
	return xpram_setup_blkdev();
}

module_init(xpram_init);
module_exit(xpram_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Xpram.c -- the S/390 expanded memory RAM-disk
	3	*
	4	* significant parts of this code are based on
	5	* the sbull device driver presented in
	6	* A. Rubini: Linux Device Drivers
	7	*
	8	* Author of XPRAM specific coding: Reinhard Buendgen
	9	* buendgen@de.ibm.com
	10	* Rewrite for 2.5: Martin Schwidefsky <schwidefsky@de.ibm.com>
	11	*
	12	* External interfaces:
	13	* Interfaces to linux kernel
	14	* xpram_setup: read kernel parameters
	15	* Device specific file operations
	16	* xpram_iotcl
	17	* xpram_open
	18	*
	19	* "ad-hoc" partitioning:
	20	* the expanded memory can be partitioned among several devices
	21	* (with different minors). The partitioning set up can be
	22	* set by kernel or module parameters (int devs & int sizes[])
	23	*
	24	* Potential future improvements:
	25	* generic hard disk support to replace ad-hoc partitioning
	26	*/
	27
	28	#include <linux/module.h>
	29	#include <linux/moduleparam.h>
	30	#include <linux/ctype.h> /* isdigit, isxdigit */
	31	#include <linux/errno.h>
	32	#include <linux/init.h>
	33	#include <linux/slab.h>
	34	#include <linux/blkdev.h>
	35	#include <linux/blkpg.h>
	36	#include <linux/hdreg.h> /* HDIO_GETGEO */
	37	#include <linux/sysdev.h>
	38	#include <linux/bio.h>
1da177e4 LT	39	#include <asm/uaccess.h>
	40
	41	#define XPRAM_NAME "xpram"
	42	#define XPRAM_DEVS 1 /* one partition */
	43	#define XPRAM_MAX_DEVS 32 /* maximal number of devices (partitions) */
	44
	45	#define PRINT_DEBUG(x...) printk(KERN_DEBUG XPRAM_NAME " debug:" x)
	46	#define PRINT_INFO(x...) printk(KERN_INFO XPRAM_NAME " info:" x)
	47	#define PRINT_WARN(x...) printk(KERN_WARNING XPRAM_NAME " warning:" x)
	48	#define PRINT_ERR(x...) printk(KERN_ERR XPRAM_NAME " error:" x)
	49
	50
1da177e4 LT	51	typedef struct {
	52	unsigned int size; /* size of xpram segment in pages */
	53	unsigned int offset; /* start page of xpram segment */
	54	} xpram_device_t;
	55
	56	static xpram_device_t xpram_devices[XPRAM_MAX_DEVS];
	57	static unsigned int xpram_sizes[XPRAM_MAX_DEVS];
	58	static struct gendisk *xpram_disks[XPRAM_MAX_DEVS];
3ce66093	59	static struct request_queue *xpram_queues[XPRAM_MAX_DEVS];
1da177e4 LT	60	static unsigned int xpram_pages;
	61	static int xpram_devs;
	62
	63	/*
	64	* Parameter parsing functions.
	65	*/
5c898ba9 HC	66	static int __initdata devs = XPRAM_DEVS;
5c898ba9 HC	67	static char __initdata *sizes[XPRAM_MAX_DEVS];
1da177e4 LT	68
1da177e4 LT	69	module_param(devs, int, 0);
5c898ba9	70	module_param_array(sizes, charp, NULL, 0);
1da177e4 LT	71
	72	MODULE_PARM_DESC(devs, "number of devices (\"partitions\"), " \
	73	"the default is " __MODULE_STRING(XPRAM_DEVS) "\n");
	74	MODULE_PARM_DESC(sizes, "list of device (partition) sizes " \
	75	"the defaults are 0s \n" \
	76	"All devices with size 0 equally partition the "
	77	"remaining space on the expanded strorage not "
	78	"claimed by explicit sizes\n");
	79	MODULE_LICENSE("GPL");
	80
1da177e4 LT	81	/*
	82	* Copy expanded memory page (4kB) into main memory
	83	* Arguments
	84	* page_addr: address of target page
	85	* xpage_index: index of expandeded memory page
	86	* Return value
	87	* 0: if operation succeeds
	88	* -EIO: if pgin failed
	89	* -ENXIO: if xpram has vanished
	90	*/
	91	static int xpram_page_in (unsigned long page_addr, unsigned int xpage_index)
	92	{
94c12cc7	93	int cc = 2; /* return unused cc 2 if pgin traps */
1da177e4	94
94c12cc7 MS	95	asm volatile(
	96	" .insn rre,0xb22e0000,%1,%2\n" /* pgin %1,%2 */
	97	"0: ipm %0\n"
	98	" srl %0,28\n"
1da177e4	99	"1:\n"
94c12cc7 MS	100	EX_TABLE(0b,1b)
94c12cc7 MS	101	: "+d" (cc) : "a" (__pa(page_addr)), "d" (xpage_index) : "cc");
1da177e4 LT	102	if (cc == 3)
1da177e4 LT	103	return -ENXIO;
8df22b4b	104	if (cc == 2)
1da177e4	105	return -ENXIO;
8df22b4b	106	if (cc == 1)
1da177e4	107	return -EIO;
1da177e4 LT	108	return 0;
	109	}
	110
	111	/*
	112	* Copy a 4kB page of main memory to an expanded memory page
	113	* Arguments
	114	* page_addr: address of source page
	115	* xpage_index: index of expandeded memory page
	116	* Return value
	117	* 0: if operation succeeds
	118	* -EIO: if pgout failed
	119	* -ENXIO: if xpram has vanished
	120	*/
	121	static long xpram_page_out (unsigned long page_addr, unsigned int xpage_index)
	122	{
94c12cc7	123	int cc = 2; /* return unused cc 2 if pgin traps */
1da177e4	124
94c12cc7 MS	125	asm volatile(
	126	" .insn rre,0xb22f0000,%1,%2\n" /* pgout %1,%2 */
	127	"0: ipm %0\n"
	128	" srl %0,28\n"
1da177e4	129	"1:\n"
94c12cc7 MS	130	EX_TABLE(0b,1b)
94c12cc7 MS	131	: "+d" (cc) : "a" (__pa(page_addr)), "d" (xpage_index) : "cc");
1da177e4 LT	132	if (cc == 3)
1da177e4 LT	133	return -ENXIO;
8df22b4b	134	if (cc == 2)
1da177e4	135	return -ENXIO;
8df22b4b	136	if (cc == 1)
1da177e4	137	return -EIO;
1da177e4 LT	138	return 0;
	139	}
	140
	141	/*
	142	* Check if xpram is available.
	143	*/
	144	static int __init xpram_present(void)
	145	{
	146	unsigned long mem_page;
	147	int rc;
	148
	149	mem_page = (unsigned long) __get_free_page(GFP_KERNEL);
	150	if (!mem_page)
	151	return -ENOMEM;
	152	rc = xpram_page_in(mem_page, 0);
	153	free_page(mem_page);
	154	return rc ? -ENXIO : 0;
	155	}
	156
	157	/*
	158	* Return index of the last available xpram page.
	159	*/
	160	static unsigned long __init xpram_highest_page_index(void)
	161	{
	162	unsigned int page_index, add_bit;
	163	unsigned long mem_page;
	164
	165	mem_page = (unsigned long) __get_free_page(GFP_KERNEL);
	166	if (!mem_page)
	167	return 0;
	168
	169	page_index = 0;
	170	add_bit = 1ULL << (sizeof(unsigned int)*8 - 1);
	171	while (add_bit > 0) {
	172	if (xpram_page_in(mem_page, page_index \| add_bit) == 0)
	173	page_index \|= add_bit;
	174	add_bit >>= 1;
	175	}
	176
	177	free_page (mem_page);
	178
	179	return page_index;
	180	}
	181
	182	/*
	183	* Block device make request function.
	184	*/
165125e1	185	static int xpram_make_request(struct request_queue q, struct bio bio)
1da177e4 LT	186	{
	187	xpram_device_t *xdev = bio->bi_bdev->bd_disk->private_data;
	188	struct bio_vec *bvec;
	189	unsigned int index;
	190	unsigned long page_addr;
	191	unsigned long bytes;
	192	int i;
	193
	194	if ((bio->bi_sector & 7) != 0 \|\| (bio->bi_size & 4095) != 0)
	195	/* Request is not page-aligned. */
	196	goto fail;
	197	if ((bio->bi_size >> 12) > xdev->size)
	198	/* Request size is no page-aligned. */
	199	goto fail;
	200	if ((bio->bi_sector >> 3) > 0xffffffffU - xdev->offset)
	201	goto fail;
	202	index = (bio->bi_sector >> 3) + xdev->offset;
	203	bio_for_each_segment(bvec, bio, i) {
	204	page_addr = (unsigned long)
	205	kmap(bvec->bv_page) + bvec->bv_offset;
	206	bytes = bvec->bv_len;
	207	if ((page_addr & 4095) != 0 \|\| (bytes & 4095) != 0)
	208	/* More paranoia. */
	209	goto fail;
	210	while (bytes > 0) {
	211	if (bio_data_dir(bio) == READ) {
	212	if (xpram_page_in(page_addr, index) != 0)
	213	goto fail;
	214	} else {
	215	if (xpram_page_out(page_addr, index) != 0)
	216	goto fail;
	217	}
	218	page_addr += 4096;
	219	bytes -= 4096;
	220	index++;
	221	}
	222	}
	223	set_bit(BIO_UPTODATE, &bio->bi_flags);
1462222b	224	bio_endio(bio, 0);
1da177e4 LT	225	return 0;
1da177e4 LT	226	fail:
6712ecf8	227	bio_io_error(bio);
1da177e4 LT	228	return 0;
	229	}
	230
a885c8c4	231	static int xpram_getgeo(struct block_device bdev, struct hd_geometry geo)
1da177e4	232	{
1da177e4	233	unsigned long size;
a885c8c4	234
1da177e4 LT	235	/*
	236	* get geometry: we have to fake one... trim the size to a
	237	* multiple of 64 (32k): tell we have 16 sectors, 4 heads,
	238	* whatever cylinders. Tell also that data starts at sector. 4.
	239	*/
1da177e4	240	size = (xpram_pages * 8) & ~0x3f;
a885c8c4 CH	241	geo->cylinders = size >> 6;
	242	geo->heads = 4;
	243	geo->sectors = 16;
	244	geo->start = 4;
1da177e4 LT	245	return 0;
	246	}
	247
	248	static struct block_device_operations xpram_devops =
	249	{
	250	.owner = THIS_MODULE,
a885c8c4	251	.getgeo = xpram_getgeo,
1da177e4 LT	252	};
	253
	254	/*
	255	* Setup xpram_sizes array.
	256	*/
	257	static int __init xpram_setup_sizes(unsigned long pages)
	258	{
	259	unsigned long mem_needed;
	260	unsigned long mem_auto;
f257b063	261	unsigned long long size;
1da177e4 LT	262	int mem_auto_no;
	263	int i;
	264
	265	/* Check number of devices. */
	266	if (devs <= 0 \|\| devs > XPRAM_MAX_DEVS) {
	267	PRINT_ERR("invalid number %d of devices\n",devs);
	268	return -EINVAL;
	269	}
	270	xpram_devs = devs;
	271
	272	/*
	273	* Copy sizes array to xpram_sizes and align partition
	274	* sizes to page boundary.
	275	*/
	276	mem_needed = 0;
	277	mem_auto_no = 0;
	278	for (i = 0; i < xpram_devs; i++) {
f257b063 HC	279	if (sizes[i]) {
	280	size = simple_strtoull(sizes[i], &sizes[i], 0);
	281	switch (sizes[i][0]) {
	282	case 'g':
	283	case 'G':
	284	size <<= 20;
	285	break;
	286	case 'm':
	287	case 'M':
	288	size <<= 10;
	289	}
	290	xpram_sizes[i] = (size + 3) & -4UL;
	291	}
1da177e4 LT	292	if (xpram_sizes[i])
	293	mem_needed += xpram_sizes[i];
	294	else
	295	mem_auto_no++;
	296	}
	297
	298	PRINT_INFO(" number of devices (partitions): %d \n", xpram_devs);
	299	for (i = 0; i < xpram_devs; i++) {
	300	if (xpram_sizes[i])
	301	PRINT_INFO(" size of partition %d: %u kB\n",
	302	i, xpram_sizes[i]);
	303	else
	304	PRINT_INFO(" size of partition %d to be set "
	305	"automatically\n",i);
	306	}
	307	PRINT_DEBUG(" memory needed (for sized partitions): %lu kB\n",
	308	mem_needed);
	309	PRINT_DEBUG(" partitions to be sized automatically: %d\n",
	310	mem_auto_no);
	311
	312	if (mem_needed > pages * 4) {
	313	PRINT_ERR("Not enough expanded memory available\n");
	314	return -EINVAL;
	315	}
	316
	317	/*
	318	* partitioning:
	319	* xpram_sizes[i] != 0; partition i has size xpram_sizes[i] kB
	320	* else: ; all partitions with zero xpram_sizes[i]
	321	* partition equally the remaining space
	322	*/
	323	if (mem_auto_no) {
	324	mem_auto = ((pages - mem_needed / 4) / mem_auto_no) * 4;
	325	PRINT_INFO(" automatically determined "
	326	"partition size: %lu kB\n", mem_auto);
	327	for (i = 0; i < xpram_devs; i++)
	328	if (xpram_sizes[i] == 0)
	329	xpram_sizes[i] = mem_auto;
	330	}
	331	return 0;
	332	}
	333
1da177e4 LT	334	static int __init xpram_setup_blkdev(void)
	335	{
	336	unsigned long offset;
	337	int i, rc = -ENOMEM;
	338
	339	for (i = 0; i < xpram_devs; i++) {
3ce66093 MS	340	xpram_disks[i] = alloc_disk(1);
	341	if (!xpram_disks[i])
	342	goto out;
	343	xpram_queues[i] = blk_alloc_queue(GFP_KERNEL);
	344	if (!xpram_queues[i]) {
	345	put_disk(xpram_disks[i]);
1da177e4	346	goto out;
3ce66093 MS	347	}
	348	blk_queue_make_request(xpram_queues[i], xpram_make_request);
	349	blk_queue_hardsect_size(xpram_queues[i], 4096);
1da177e4 LT	350	}
	351
	352	/*
	353	* Register xpram major.
	354	*/
	355	rc = register_blkdev(XPRAM_MAJOR, XPRAM_NAME);
	356	if (rc < 0)
	357	goto out;
	358
1da177e4 LT	359	/*
	360	* Setup device structures.
	361	*/
	362	offset = 0;
	363	for (i = 0; i < xpram_devs; i++) {
	364	struct gendisk *disk = xpram_disks[i];
	365
	366	xpram_devices[i].size = xpram_sizes[i] / 4;
	367	xpram_devices[i].offset = offset;
	368	offset += xpram_devices[i].size;
	369	disk->major = XPRAM_MAJOR;
	370	disk->first_minor = i;
	371	disk->fops = &xpram_devops;
	372	disk->private_data = &xpram_devices[i];
3ce66093	373	disk->queue = xpram_queues[i];
1da177e4	374	sprintf(disk->disk_name, "slram%d", i);
1da177e4 LT	375	set_capacity(disk, xpram_sizes[i] << 1);
	376	add_disk(disk);
	377	}
	378
	379	return 0;
1da177e4	380	out:
3ce66093 MS	381	while (i--) {
3ce66093 MS	382	blk_cleanup_queue(xpram_queues[i]);
1da177e4	383	put_disk(xpram_disks[i]);
3ce66093	384	}
1da177e4 LT	385	return rc;
	386	}
	387
	388	/*
	389	* Finally, the init/exit functions.
	390	*/
	391	static void __exit xpram_exit(void)
	392	{
	393	int i;
	394	for (i = 0; i < xpram_devs; i++) {
	395	del_gendisk(xpram_disks[i]);
3ce66093	396	blk_cleanup_queue(xpram_queues[i]);
1da177e4 LT	397	put_disk(xpram_disks[i]);
	398	}
	399	unregister_blkdev(XPRAM_MAJOR, XPRAM_NAME);
1da177e4 LT	400	}
	401
	402	static int __init xpram_init(void)
	403	{
	404	int rc;
	405
	406	/* Find out size of expanded memory. */
	407	if (xpram_present() != 0) {
	408	PRINT_WARN("No expanded memory available\n");
	409	return -ENODEV;
	410	}
e620c494	411	xpram_pages = xpram_highest_page_index() + 1;
1da177e4 LT	412	PRINT_INFO(" %u pages expanded memory found (%lu KB).\n",
	413	xpram_pages, (unsigned long) xpram_pages*4);
	414	rc = xpram_setup_sizes(xpram_pages);
	415	if (rc)
	416	return rc;
37ab46a3	417	return xpram_setup_blkdev();
1da177e4 LT	418	}
	419
	420	module_init(xpram_init);
	421	module_exit(xpram_exit);