1 // SPDX-License-Identifier: GPL-2.0
3  * Xpram.c -- the S/390 expanded memory RAM-disk
14  *   Interfaces to linux kernel
20  * "ad-hoc" partitioning:
26  *   generic hard disk support to replace ad-hoc partitioning
42 #include <linux/suspend.h>
88  *           -EIO:         if pgin failed
89  *           -ENXIO:       if xpram has vanished
103 		return -ENXIO;  in xpram_page_in()
105 		return -ENXIO;  in xpram_page_in()
107 		return -EIO;  in xpram_page_in()
112  * Copy a 4kB page of main memory to an expanded memory page          
118  *           -EIO:         if pgout failed
119  *           -ENXIO:       if xpram has vanished
133 		return -ENXIO;  in xpram_page_out()
135 		return -ENXIO;  in xpram_page_out()
137 		return -EIO;  in xpram_page_out()
151 		return -ENOMEM;  in xpram_present()
154 	return rc ? -ENXIO : 0;  in xpram_present()
170 	add_bit = 1ULL << (sizeof(unsigned int)*8 - 1);  in xpram_highest_page_index()
187 	xpram_device_t *xdev = bio->bi_disk->private_data;  in xpram_submit_bio()
196 	if ((bio->bi_iter.bi_sector & 7) != 0 ||  in xpram_submit_bio()
197 	    (bio->bi_iter.bi_size & 4095) != 0)  in xpram_submit_bio()
198 		/* Request is not page-aligned. */  in xpram_submit_bio()
200 	if ((bio->bi_iter.bi_size >> 12) > xdev->size)  in xpram_submit_bio()
201 		/* Request size is no page-aligned. */  in xpram_submit_bio()
203 	if ((bio->bi_iter.bi_sector >> 3) > 0xffffffffU - xdev->offset)  in xpram_submit_bio()
205 	index = (bio->bi_iter.bi_sector >> 3) + xdev->offset;  in xpram_submit_bio()
222 			bytes -= 4096;  in xpram_submit_bio()
238 	 * get geometry: we have to fake one...  trim the size to a  in xpram_getgeo()
243 	geo->cylinders = size >> 6;  in xpram_getgeo()
244 	geo->heads = 4;  in xpram_getgeo()
245 	geo->sectors = 16;  in xpram_getgeo()
246 	geo->start = 4;  in xpram_getgeo()
272 		return -EINVAL;  in xpram_setup_sizes()
277 	 * Copy sizes array to xpram_sizes and align partition  in xpram_setup_sizes()
278 	 * sizes to page boundary.  in xpram_setup_sizes()
294 			xpram_sizes[i] = (size + 3) & -4UL;  in xpram_setup_sizes()
308 			pr_info("  size of partition %d to be set "  in xpram_setup_sizes()
313 	pr_info("  partitions to be sized automatically: %d\n",  in xpram_setup_sizes()
318 		return -EINVAL;  in xpram_setup_sizes()
328 		mem_auto = ((pages - mem_needed / 4) / mem_auto_no) * 4;  in xpram_setup_sizes()
341 	int i, rc = -ENOMEM;  in xpram_setup_blkdev()
369 		struct gendisk *disk = xpram_disks[i];  in xpram_setup_blkdev()  local
374 		disk->major = XPRAM_MAJOR;  in xpram_setup_blkdev()
375 		disk->first_minor = i;  in xpram_setup_blkdev()
376 		disk->fops = &xpram_devops;  in xpram_setup_blkdev()
377 		disk->private_data = &xpram_devices[i];  in xpram_setup_blkdev()
378 		disk->queue = xpram_queues[i];  in xpram_setup_blkdev()
379 		sprintf(disk->disk_name, "slram%d", i);  in xpram_setup_blkdev()
380 		set_capacity(disk, xpram_sizes[i] << 1);  in xpram_setup_blkdev()
381 		add_disk(disk);  in xpram_setup_blkdev()
386 	while (i--) {  in xpram_setup_blkdev()
403  * Check if xpram setup changed between suspend and resume.
452 		return -ENODEV;  in xpram_init()
463 	xpram_pdev = platform_device_register_simple(XPRAM_NAME, -1, NULL, 0);  in xpram_init()