Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/drivers/s390/block/xpram.c b/drivers/s390/block/xpram.c
new file mode 100644
index 0000000..d428c90
--- /dev/null
+++ b/drivers/s390/block/xpram.c
@@ -0,0 +1,539 @@
+/*
+ * 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 <linux/devfs_fs_kernel.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)
+
+
+static struct sysdev_class xpram_sysclass = {
+	set_kset_name("xpram"),
+};
+
+static struct sys_device xpram_sys_device = {
+	.id	= 0,
+	.cls	= &xpram_sysclass,
+}; 
+
+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 unsigned int xpram_pages;
+static int xpram_devs;
+
+/*
+ * Parameter parsing functions.
+ */
+static int devs = XPRAM_DEVS;
+static unsigned int sizes[XPRAM_MAX_DEVS];
+
+module_param(devs, int, 0);
+module_param_array(sizes, int, 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");
+
+#ifndef MODULE
+/*
+ * Parses the kernel parameters given in the kernel parameter line.
+ * The expected format is
+ *           <number_of_partitions>[","<partition_size>]*
+ * where
+ *           devices is a positive integer that initializes xpram_devs
+ *           each size is a non-negative integer possibly followed by a
+ *           magnitude (k,K,m,M,g,G), the list of sizes initialises
+ *           xpram_sizes
+ *
+ * Arguments
+ *           str: substring of kernel parameter line that contains xprams
+ *                kernel parameters.
+ *
+ * Result    0 on success, -EINVAL else -- only for Version > 2.3
+ *
+ * Side effects
+ *           the global variabls devs is set to the value of
+ *           <number_of_partitions> and sizes[i] is set to the i-th
+ *           partition size (if provided). A parsing error of a value
+ *           results in this value being set to -EINVAL.
+ */
+static int __init xpram_setup (char *str)
+{
+	char *cp;
+	int i;
+
+	devs = simple_strtoul(str, &cp, 10);
+	if (cp <= str || devs > XPRAM_MAX_DEVS)
+		return 0;
+	for (i = 0; (i < devs) && (*cp++ == ','); i++) {
+		sizes[i] = simple_strtoul(cp, &cp, 10);
+		if (*cp == 'g' || *cp == 'G') {
+			sizes[i] <<= 20;
+			cp++;
+		} else if (*cp == 'm' || *cp == 'M') {
+			sizes[i] <<= 10;
+			cp++;
+		} else if (*cp == 'k' || *cp == 'K')
+			cp++;
+		while (isspace(*cp)) cp++;
+	}
+	if (*cp == ',' && i >= devs)
+		PRINT_WARN("partition sizes list has too many entries.\n");
+	else if (*cp != 0)
+		PRINT_WARN("ignored '%s' at end of parameter string.\n", cp);
+	return 1;
+}
+
+__setup("xpram_parts=", xpram_setup);
+#endif
+
+/*
+ * 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;
+
+	__asm__ __volatile__ (
+		"   lhi   %0,2\n"  /* return unused cc 2 if pgin traps */
+		"   .insn rre,0xb22e0000,%1,%2\n"  /* pgin %1,%2 */
+                "0: ipm   %0\n"
+		"   srl   %0,28\n"
+		"1:\n"
+#ifndef CONFIG_ARCH_S390X
+		".section __ex_table,\"a\"\n"
+		"   .align 4\n"
+		"   .long  0b,1b\n"
+		".previous"
+#else
+                ".section __ex_table,\"a\"\n"
+                "   .align 8\n"
+                "   .quad 0b,1b\n"
+                ".previous"
+#endif
+		: "=&d" (cc) 
+		: "a" (__pa(page_addr)), "a" (xpage_index) 
+		: "cc" );
+	if (cc == 3)
+		return -ENXIO;
+	if (cc == 2) {
+		PRINT_ERR("expanded storage lost!\n");
+		return -ENXIO;
+	}
+	if (cc == 1) {
+		PRINT_ERR("page in failed for page index %u.\n",
+			  xpage_index);
+		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;
+
+	__asm__ __volatile__ (
+		"   lhi   %0,2\n"  /* return unused cc 2 if pgout traps */
+		"   .insn rre,0xb22f0000,%1,%2\n"  /* pgout %1,%2 */
+                "0: ipm   %0\n"
+		"   srl   %0,28\n"
+		"1:\n"
+#ifndef CONFIG_ARCH_S390X
+		".section __ex_table,\"a\"\n"
+		"   .align 4\n"
+		"   .long  0b,1b\n"
+		".previous"
+#else
+                ".section __ex_table,\"a\"\n"
+                "   .align 8\n"
+                "   .quad 0b,1b\n"
+                ".previous"
+#endif
+		: "=&d" (cc) 
+		: "a" (__pa(page_addr)), "a" (xpage_index) 
+		: "cc" );
+	if (cc == 3)
+		return -ENXIO;
+	if (cc == 2) {
+		PRINT_ERR("expanded storage lost!\n");
+		return -ENXIO;
+	}
+	if (cc == 1) {
+		PRINT_ERR("page out failed for page index %u.\n",
+			  xpage_index);
+		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(request_queue_t *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);
+	bytes = bio->bi_size;
+	bio->bi_size = 0;
+	bio->bi_end_io(bio, bytes, 0);
+	return 0;
+fail:
+	bio_io_error(bio, bio->bi_size);
+	return 0;
+}
+
+static int xpram_ioctl (struct inode *inode, struct file *filp,
+		 unsigned int cmd, unsigned long arg)
+{
+	struct hd_geometry __user *geo;
+	unsigned long size;
+	if (cmd != HDIO_GETGEO)
+		return -EINVAL;
+	/*
+	 * 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.
+	 */
+	geo = (struct hd_geometry __user *) arg;
+	size = (xpram_pages * 8) & ~0x3f;
+	put_user(size >> 6, &geo->cylinders);
+	put_user(4, &geo->heads);
+	put_user(16, &geo->sectors);
+	put_user(4, &geo->start);
+	return 0;
+}
+
+static struct block_device_operations xpram_devops =
+{
+	.owner	= THIS_MODULE,
+	.ioctl	= xpram_ioctl,
+};
+
+/*
+ * Setup xpram_sizes array.
+ */
+static int __init xpram_setup_sizes(unsigned long pages)
+{
+	unsigned long mem_needed;
+	unsigned long mem_auto;
+	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++) {
+		xpram_sizes[i] = (sizes[i] + 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 struct request_queue *xpram_queue;
+
+static int __init xpram_setup_blkdev(void)
+{
+	unsigned long offset;
+	int i, rc = -ENOMEM;
+
+	for (i = 0; i < xpram_devs; i++) {
+		struct gendisk *disk = alloc_disk(1);
+		if (!disk)
+			goto out;
+		xpram_disks[i] = disk;
+	}
+
+	/*
+	 * Register xpram major.
+	 */
+	rc = register_blkdev(XPRAM_MAJOR, XPRAM_NAME);
+	if (rc < 0)
+		goto out;
+
+	devfs_mk_dir("slram");
+
+	/*
+	 * Assign the other needed values: make request function, sizes and
+	 * hardsect size. All the minor devices feature the same value.
+	 */
+	xpram_queue = blk_alloc_queue(GFP_KERNEL);
+	if (!xpram_queue) {
+		rc = -ENOMEM;
+		goto out_unreg;
+	}
+	blk_queue_make_request(xpram_queue, xpram_make_request);
+	blk_queue_hardsect_size(xpram_queue, 4096);
+
+	/*
+	 * 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_queue;
+		sprintf(disk->disk_name, "slram%d", i);
+		sprintf(disk->devfs_name, "slram/%d", i);
+		set_capacity(disk, xpram_sizes[i] << 1);
+		add_disk(disk);
+	}
+
+	return 0;
+out_unreg:
+	devfs_remove("slram");
+	unregister_blkdev(XPRAM_MAJOR, XPRAM_NAME);
+out:
+	while (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]);
+		put_disk(xpram_disks[i]);
+	}
+	unregister_blkdev(XPRAM_MAJOR, XPRAM_NAME);
+	devfs_remove("slram");
+	blk_cleanup_queue(xpram_queue);
+	sysdev_unregister(&xpram_sys_device);
+	sysdev_class_unregister(&xpram_sysclass);
+}
+
+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();
+	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;
+	rc = sysdev_class_register(&xpram_sysclass);
+	if (rc)
+		return rc;
+
+	rc = sysdev_register(&xpram_sys_device);
+	if (rc) {
+		sysdev_class_unregister(&xpram_sysclass);
+		return rc;
+	}
+	rc = xpram_setup_blkdev();
+	if (rc)
+		sysdev_unregister(&xpram_sys_device);
+	return rc;
+}
+
+module_init(xpram_init);
+module_exit(xpram_exit);