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/dcssblk.c b/drivers/s390/block/dcssblk.c
new file mode 100644
index 0000000..a66b17b6
--- /dev/null
+++ b/drivers/s390/block/dcssblk.c
@@ -0,0 +1,775 @@
+/*
+ * dcssblk.c -- the S/390 block driver for dcss memory
+ *
+ * Authors: Carsten Otte, Stefan Weinhuber, Gerald Schaefer
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include <asm/extmem.h>
+#include <asm/io.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <asm/ccwdev.h> // for s390_root_dev_(un)register()
+
+//#define DCSSBLK_DEBUG /* Debug messages on/off */
+#define DCSSBLK_NAME "dcssblk"
+#define DCSSBLK_MINORS_PER_DISK 1
+#define DCSSBLK_PARM_LEN 400
+
+#ifdef DCSSBLK_DEBUG
+#define PRINT_DEBUG(x...) printk(KERN_DEBUG DCSSBLK_NAME " debug: " x)
+#else
+#define PRINT_DEBUG(x...) do {} while (0)
+#endif
+#define PRINT_INFO(x...) printk(KERN_INFO DCSSBLK_NAME " info: " x)
+#define PRINT_WARN(x...) printk(KERN_WARNING DCSSBLK_NAME " warning: " x)
+#define PRINT_ERR(x...) printk(KERN_ERR DCSSBLK_NAME " error: " x)
+
+
+static int dcssblk_open(struct inode *inode, struct file *filp);
+static int dcssblk_release(struct inode *inode, struct file *filp);
+static int dcssblk_make_request(struct request_queue *q, struct bio *bio);
+
+static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
+
+static int dcssblk_major;
+static struct block_device_operations dcssblk_devops = {
+ .owner = THIS_MODULE,
+ .open = dcssblk_open,
+ .release = dcssblk_release,
+};
+
+static ssize_t dcssblk_add_store(struct device * dev, const char * buf,
+ size_t count);
+static ssize_t dcssblk_remove_store(struct device * dev, const char * buf,
+ size_t count);
+static ssize_t dcssblk_save_store(struct device * dev, const char * buf,
+ size_t count);
+static ssize_t dcssblk_save_show(struct device *dev, char *buf);
+static ssize_t dcssblk_shared_store(struct device * dev, const char * buf,
+ size_t count);
+static ssize_t dcssblk_shared_show(struct device *dev, char *buf);
+
+static DEVICE_ATTR(add, S_IWUSR, NULL, dcssblk_add_store);
+static DEVICE_ATTR(remove, S_IWUSR, NULL, dcssblk_remove_store);
+static DEVICE_ATTR(save, S_IWUSR | S_IRUGO, dcssblk_save_show,
+ dcssblk_save_store);
+static DEVICE_ATTR(shared, S_IWUSR | S_IRUGO, dcssblk_shared_show,
+ dcssblk_shared_store);
+
+static struct device *dcssblk_root_dev;
+
+struct dcssblk_dev_info {
+ struct list_head lh;
+ struct device dev;
+ char segment_name[BUS_ID_SIZE];
+ atomic_t use_count;
+ struct gendisk *gd;
+ unsigned long start;
+ unsigned long end;
+ int segment_type;
+ unsigned char save_pending;
+ unsigned char is_shared;
+ struct request_queue *dcssblk_queue;
+};
+
+static struct list_head dcssblk_devices = LIST_HEAD_INIT(dcssblk_devices);
+static struct rw_semaphore dcssblk_devices_sem;
+
+/*
+ * release function for segment device.
+ */
+static void
+dcssblk_release_segment(struct device *dev)
+{
+ PRINT_DEBUG("segment release fn called for %s\n", dev->bus_id);
+ kfree(container_of(dev, struct dcssblk_dev_info, dev));
+ module_put(THIS_MODULE);
+}
+
+/*
+ * get a minor number. needs to be called with
+ * down_write(&dcssblk_devices_sem) and the
+ * device needs to be enqueued before the semaphore is
+ * freed.
+ */
+static inline int
+dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info)
+{
+ int minor, found;
+ struct dcssblk_dev_info *entry;
+
+ if (dev_info == NULL)
+ return -EINVAL;
+ for (minor = 0; minor < (1<<MINORBITS); minor++) {
+ found = 0;
+ // test if minor available
+ list_for_each_entry(entry, &dcssblk_devices, lh)
+ if (minor == entry->gd->first_minor)
+ found++;
+ if (!found) break; // got unused minor
+ }
+ if (found)
+ return -EBUSY;
+ dev_info->gd->first_minor = minor;
+ return 0;
+}
+
+/*
+ * get the struct dcssblk_dev_info from dcssblk_devices
+ * for the given name.
+ * down_read(&dcssblk_devices_sem) must be held.
+ */
+static struct dcssblk_dev_info *
+dcssblk_get_device_by_name(char *name)
+{
+ struct dcssblk_dev_info *entry;
+
+ list_for_each_entry(entry, &dcssblk_devices, lh) {
+ if (!strcmp(name, entry->segment_name)) {
+ return entry;
+ }
+ }
+ return NULL;
+}
+
+/*
+ * print appropriate error message for segment_load()/segment_type()
+ * return code
+ */
+static void
+dcssblk_segment_warn(int rc, char* seg_name)
+{
+ switch (rc) {
+ case -ENOENT:
+ PRINT_WARN("cannot load/query segment %s, does not exist\n",
+ seg_name);
+ break;
+ case -ENOSYS:
+ PRINT_WARN("cannot load/query segment %s, not running on VM\n",
+ seg_name);
+ break;
+ case -EIO:
+ PRINT_WARN("cannot load/query segment %s, hardware error\n",
+ seg_name);
+ break;
+ case -ENOTSUPP:
+ PRINT_WARN("cannot load/query segment %s, is a multi-part "
+ "segment\n", seg_name);
+ break;
+ case -ENOSPC:
+ PRINT_WARN("cannot load/query segment %s, overlaps with "
+ "storage\n", seg_name);
+ break;
+ case -EBUSY:
+ PRINT_WARN("cannot load/query segment %s, overlaps with "
+ "already loaded dcss\n", seg_name);
+ break;
+ case -EPERM:
+ PRINT_WARN("cannot load/query segment %s, already loaded in "
+ "incompatible mode\n", seg_name);
+ break;
+ case -ENOMEM:
+ PRINT_WARN("cannot load/query segment %s, out of memory\n",
+ seg_name);
+ break;
+ case -ERANGE:
+ PRINT_WARN("cannot load/query segment %s, exceeds kernel "
+ "mapping range\n", seg_name);
+ break;
+ default:
+ PRINT_WARN("cannot load/query segment %s, return value %i\n",
+ seg_name, rc);
+ break;
+ }
+}
+
+/*
+ * device attribute for switching shared/nonshared (exclusive)
+ * operation (show + store)
+ */
+static ssize_t
+dcssblk_shared_show(struct device *dev, char *buf)
+{
+ struct dcssblk_dev_info *dev_info;
+
+ dev_info = container_of(dev, struct dcssblk_dev_info, dev);
+ return sprintf(buf, dev_info->is_shared ? "1\n" : "0\n");
+}
+
+static ssize_t
+dcssblk_shared_store(struct device *dev, const char *inbuf, size_t count)
+{
+ struct dcssblk_dev_info *dev_info;
+ int rc;
+
+ if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) {
+ PRINT_WARN("Invalid value, must be 0 or 1\n");
+ return -EINVAL;
+ }
+ down_write(&dcssblk_devices_sem);
+ dev_info = container_of(dev, struct dcssblk_dev_info, dev);
+ if (atomic_read(&dev_info->use_count)) {
+ PRINT_ERR("share: segment %s is busy!\n",
+ dev_info->segment_name);
+ rc = -EBUSY;
+ goto out;
+ }
+ if (inbuf[0] == '1') {
+ // reload segment in shared mode
+ rc = segment_modify_shared(dev_info->segment_name,
+ SEGMENT_SHARED);
+ if (rc < 0) {
+ BUG_ON(rc == -EINVAL);
+ if (rc == -EIO || rc == -ENOENT)
+ goto removeseg;
+ } else {
+ dev_info->is_shared = 1;
+ switch (dev_info->segment_type) {
+ case SEG_TYPE_SR:
+ case SEG_TYPE_ER:
+ case SEG_TYPE_SC:
+ set_disk_ro(dev_info->gd,1);
+ }
+ }
+ } else if (inbuf[0] == '0') {
+ // reload segment in exclusive mode
+ if (dev_info->segment_type == SEG_TYPE_SC) {
+ PRINT_ERR("Segment type SC (%s) cannot be loaded in "
+ "non-shared mode\n", dev_info->segment_name);
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = segment_modify_shared(dev_info->segment_name,
+ SEGMENT_EXCLUSIVE);
+ if (rc < 0) {
+ BUG_ON(rc == -EINVAL);
+ if (rc == -EIO || rc == -ENOENT)
+ goto removeseg;
+ } else {
+ dev_info->is_shared = 0;
+ set_disk_ro(dev_info->gd, 0);
+ }
+ } else {
+ PRINT_WARN("Invalid value, must be 0 or 1\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = count;
+ goto out;
+
+removeseg:
+ PRINT_ERR("Could not reload segment %s, removing it now!\n",
+ dev_info->segment_name);
+ list_del(&dev_info->lh);
+
+ del_gendisk(dev_info->gd);
+ blk_put_queue(dev_info->dcssblk_queue);
+ dev_info->gd->queue = NULL;
+ put_disk(dev_info->gd);
+ device_unregister(dev);
+ put_device(dev);
+out:
+ up_write(&dcssblk_devices_sem);
+ return rc;
+}
+
+/*
+ * device attribute for save operation on current copy
+ * of the segment. If the segment is busy, saving will
+ * become pending until it gets released, which can be
+ * undone by storing a non-true value to this entry.
+ * (show + store)
+ */
+static ssize_t
+dcssblk_save_show(struct device *dev, char *buf)
+{
+ struct dcssblk_dev_info *dev_info;
+
+ dev_info = container_of(dev, struct dcssblk_dev_info, dev);
+ return sprintf(buf, dev_info->save_pending ? "1\n" : "0\n");
+}
+
+static ssize_t
+dcssblk_save_store(struct device *dev, const char *inbuf, size_t count)
+{
+ struct dcssblk_dev_info *dev_info;
+
+ if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) {
+ PRINT_WARN("Invalid value, must be 0 or 1\n");
+ return -EINVAL;
+ }
+ dev_info = container_of(dev, struct dcssblk_dev_info, dev);
+
+ down_write(&dcssblk_devices_sem);
+ if (inbuf[0] == '1') {
+ if (atomic_read(&dev_info->use_count) == 0) {
+ // device is idle => we save immediately
+ PRINT_INFO("Saving segment %s\n",
+ dev_info->segment_name);
+ segment_save(dev_info->segment_name);
+ } else {
+ // device is busy => we save it when it becomes
+ // idle in dcssblk_release
+ PRINT_INFO("Segment %s is currently busy, it will "
+ "be saved when it becomes idle...\n",
+ dev_info->segment_name);
+ dev_info->save_pending = 1;
+ }
+ } else if (inbuf[0] == '0') {
+ if (dev_info->save_pending) {
+ // device is busy & the user wants to undo his save
+ // request
+ dev_info->save_pending = 0;
+ PRINT_INFO("Pending save for segment %s deactivated\n",
+ dev_info->segment_name);
+ }
+ } else {
+ up_write(&dcssblk_devices_sem);
+ PRINT_WARN("Invalid value, must be 0 or 1\n");
+ return -EINVAL;
+ }
+ up_write(&dcssblk_devices_sem);
+ return count;
+}
+
+/*
+ * device attribute for adding devices
+ */
+static ssize_t
+dcssblk_add_store(struct device *dev, const char *buf, size_t count)
+{
+ int rc, i;
+ struct dcssblk_dev_info *dev_info;
+ char *local_buf;
+ unsigned long seg_byte_size;
+
+ dev_info = NULL;
+ if (dev != dcssblk_root_dev) {
+ rc = -EINVAL;
+ goto out_nobuf;
+ }
+ local_buf = kmalloc(count + 1, GFP_KERNEL);
+ if (local_buf == NULL) {
+ rc = -ENOMEM;
+ goto out_nobuf;
+ }
+ /*
+ * parse input
+ */
+ for (i = 0; ((buf[i] != '\0') && (buf[i] != '\n') && i < count); i++) {
+ local_buf[i] = toupper(buf[i]);
+ }
+ local_buf[i] = '\0';
+ if ((i == 0) || (i > 8)) {
+ rc = -ENAMETOOLONG;
+ goto out;
+ }
+ /*
+ * already loaded?
+ */
+ down_read(&dcssblk_devices_sem);
+ dev_info = dcssblk_get_device_by_name(local_buf);
+ up_read(&dcssblk_devices_sem);
+ if (dev_info != NULL) {
+ PRINT_WARN("Segment %s already loaded!\n", local_buf);
+ rc = -EEXIST;
+ goto out;
+ }
+ /*
+ * get a struct dcssblk_dev_info
+ */
+ dev_info = kmalloc(sizeof(struct dcssblk_dev_info), GFP_KERNEL);
+ if (dev_info == NULL) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ memset(dev_info, 0, sizeof(struct dcssblk_dev_info));
+
+ strcpy(dev_info->segment_name, local_buf);
+ strlcpy(dev_info->dev.bus_id, local_buf, BUS_ID_SIZE);
+ dev_info->dev.release = dcssblk_release_segment;
+ INIT_LIST_HEAD(&dev_info->lh);
+
+ dev_info->gd = alloc_disk(DCSSBLK_MINORS_PER_DISK);
+ if (dev_info->gd == NULL) {
+ rc = -ENOMEM;
+ goto free_dev_info;
+ }
+ dev_info->gd->major = dcssblk_major;
+ dev_info->gd->fops = &dcssblk_devops;
+ dev_info->dcssblk_queue = blk_alloc_queue(GFP_KERNEL);
+ dev_info->gd->queue = dev_info->dcssblk_queue;
+ dev_info->gd->private_data = dev_info;
+ dev_info->gd->driverfs_dev = &dev_info->dev;
+ /*
+ * load the segment
+ */
+ rc = segment_load(local_buf, SEGMENT_SHARED,
+ &dev_info->start, &dev_info->end);
+ if (rc < 0) {
+ dcssblk_segment_warn(rc, dev_info->segment_name);
+ goto dealloc_gendisk;
+ }
+ seg_byte_size = (dev_info->end - dev_info->start + 1);
+ set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors
+ PRINT_INFO("Loaded segment %s, size = %lu Byte, "
+ "capacity = %lu (512 Byte) sectors\n", local_buf,
+ seg_byte_size, seg_byte_size >> 9);
+
+ dev_info->segment_type = rc;
+ dev_info->save_pending = 0;
+ dev_info->is_shared = 1;
+ dev_info->dev.parent = dcssblk_root_dev;
+
+ /*
+ * get minor, add to list
+ */
+ down_write(&dcssblk_devices_sem);
+ rc = dcssblk_assign_free_minor(dev_info);
+ if (rc) {
+ up_write(&dcssblk_devices_sem);
+ PRINT_ERR("No free minor number available! "
+ "Unloading segment...\n");
+ goto unload_seg;
+ }
+ sprintf(dev_info->gd->disk_name, "dcssblk%d",
+ dev_info->gd->first_minor);
+ list_add_tail(&dev_info->lh, &dcssblk_devices);
+
+ if (!try_module_get(THIS_MODULE)) {
+ rc = -ENODEV;
+ goto list_del;
+ }
+ /*
+ * register the device
+ */
+ rc = device_register(&dev_info->dev);
+ if (rc) {
+ PRINT_ERR("Segment %s could not be registered RC=%d\n",
+ local_buf, rc);
+ module_put(THIS_MODULE);
+ goto list_del;
+ }
+ get_device(&dev_info->dev);
+ rc = device_create_file(&dev_info->dev, &dev_attr_shared);
+ if (rc)
+ goto unregister_dev;
+ rc = device_create_file(&dev_info->dev, &dev_attr_save);
+ if (rc)
+ goto unregister_dev;
+
+ add_disk(dev_info->gd);
+
+ blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request);
+ blk_queue_hardsect_size(dev_info->dcssblk_queue, 4096);
+
+ switch (dev_info->segment_type) {
+ case SEG_TYPE_SR:
+ case SEG_TYPE_ER:
+ case SEG_TYPE_SC:
+ set_disk_ro(dev_info->gd,1);
+ break;
+ default:
+ set_disk_ro(dev_info->gd,0);
+ break;
+ }
+ PRINT_DEBUG("Segment %s loaded successfully\n", local_buf);
+ up_write(&dcssblk_devices_sem);
+ rc = count;
+ goto out;
+
+unregister_dev:
+ PRINT_ERR("device_create_file() failed!\n");
+ list_del(&dev_info->lh);
+ blk_put_queue(dev_info->dcssblk_queue);
+ dev_info->gd->queue = NULL;
+ put_disk(dev_info->gd);
+ device_unregister(&dev_info->dev);
+ segment_unload(dev_info->segment_name);
+ put_device(&dev_info->dev);
+ up_write(&dcssblk_devices_sem);
+ goto out;
+list_del:
+ list_del(&dev_info->lh);
+ up_write(&dcssblk_devices_sem);
+unload_seg:
+ segment_unload(local_buf);
+dealloc_gendisk:
+ blk_put_queue(dev_info->dcssblk_queue);
+ dev_info->gd->queue = NULL;
+ put_disk(dev_info->gd);
+free_dev_info:
+ kfree(dev_info);
+out:
+ kfree(local_buf);
+out_nobuf:
+ return rc;
+}
+
+/*
+ * device attribute for removing devices
+ */
+static ssize_t
+dcssblk_remove_store(struct device *dev, const char *buf, size_t count)
+{
+ struct dcssblk_dev_info *dev_info;
+ int rc, i;
+ char *local_buf;
+
+ if (dev != dcssblk_root_dev) {
+ return -EINVAL;
+ }
+ local_buf = kmalloc(count + 1, GFP_KERNEL);
+ if (local_buf == NULL) {
+ return -ENOMEM;
+ }
+ /*
+ * parse input
+ */
+ for (i = 0; ((*(buf+i)!='\0') && (*(buf+i)!='\n') && i < count); i++) {
+ local_buf[i] = toupper(buf[i]);
+ }
+ local_buf[i] = '\0';
+ if ((i == 0) || (i > 8)) {
+ rc = -ENAMETOOLONG;
+ goto out_buf;
+ }
+
+ down_write(&dcssblk_devices_sem);
+ dev_info = dcssblk_get_device_by_name(local_buf);
+ if (dev_info == NULL) {
+ up_write(&dcssblk_devices_sem);
+ PRINT_WARN("Segment %s is not loaded!\n", local_buf);
+ rc = -ENODEV;
+ goto out_buf;
+ }
+ if (atomic_read(&dev_info->use_count) != 0) {
+ up_write(&dcssblk_devices_sem);
+ PRINT_WARN("Segment %s is in use!\n", local_buf);
+ rc = -EBUSY;
+ goto out_buf;
+ }
+ list_del(&dev_info->lh);
+
+ del_gendisk(dev_info->gd);
+ blk_put_queue(dev_info->dcssblk_queue);
+ dev_info->gd->queue = NULL;
+ put_disk(dev_info->gd);
+ device_unregister(&dev_info->dev);
+ segment_unload(dev_info->segment_name);
+ PRINT_DEBUG("Segment %s unloaded successfully\n",
+ dev_info->segment_name);
+ put_device(&dev_info->dev);
+ up_write(&dcssblk_devices_sem);
+
+ rc = count;
+out_buf:
+ kfree(local_buf);
+ return rc;
+}
+
+static int
+dcssblk_open(struct inode *inode, struct file *filp)
+{
+ struct dcssblk_dev_info *dev_info;
+ int rc;
+
+ dev_info = inode->i_bdev->bd_disk->private_data;
+ if (NULL == dev_info) {
+ rc = -ENODEV;
+ goto out;
+ }
+ atomic_inc(&dev_info->use_count);
+ inode->i_bdev->bd_block_size = 4096;
+ rc = 0;
+out:
+ return rc;
+}
+
+static int
+dcssblk_release(struct inode *inode, struct file *filp)
+{
+ struct dcssblk_dev_info *dev_info;
+ int rc;
+
+ dev_info = inode->i_bdev->bd_disk->private_data;
+ if (NULL == dev_info) {
+ rc = -ENODEV;
+ goto out;
+ }
+ down_write(&dcssblk_devices_sem);
+ if (atomic_dec_and_test(&dev_info->use_count)
+ && (dev_info->save_pending)) {
+ PRINT_INFO("Segment %s became idle and is being saved now\n",
+ dev_info->segment_name);
+ segment_save(dev_info->segment_name);
+ dev_info->save_pending = 0;
+ }
+ up_write(&dcssblk_devices_sem);
+ rc = 0;
+out:
+ return rc;
+}
+
+static int
+dcssblk_make_request(request_queue_t *q, struct bio *bio)
+{
+ struct dcssblk_dev_info *dev_info;
+ struct bio_vec *bvec;
+ unsigned long index;
+ unsigned long page_addr;
+ unsigned long source_addr;
+ unsigned long bytes_done;
+ int i;
+
+ bytes_done = 0;
+ dev_info = bio->bi_bdev->bd_disk->private_data;
+ if (dev_info == NULL)
+ goto fail;
+ if ((bio->bi_sector & 7) != 0 || (bio->bi_size & 4095) != 0)
+ /* Request is not page-aligned. */
+ goto fail;
+ if (((bio->bi_size >> 9) + bio->bi_sector)
+ > get_capacity(bio->bi_bdev->bd_disk)) {
+ /* Request beyond end of DCSS segment. */
+ goto fail;
+ }
+ index = (bio->bi_sector >> 3);
+ bio_for_each_segment(bvec, bio, i) {
+ page_addr = (unsigned long)
+ page_address(bvec->bv_page) + bvec->bv_offset;
+ source_addr = dev_info->start + (index<<12) + bytes_done;
+ if (unlikely(page_addr & 4095) != 0 || (bvec->bv_len & 4095) != 0)
+ // More paranoia.
+ goto fail;
+ if (bio_data_dir(bio) == READ) {
+ memcpy((void*)page_addr, (void*)source_addr,
+ bvec->bv_len);
+ } else {
+ memcpy((void*)source_addr, (void*)page_addr,
+ bvec->bv_len);
+ }
+ bytes_done += bvec->bv_len;
+ }
+ bio_endio(bio, bytes_done, 0);
+ return 0;
+fail:
+ bio_io_error(bio, bytes_done);
+ return 0;
+}
+
+static void
+dcssblk_check_params(void)
+{
+ int rc, i, j, k;
+ char buf[9];
+ struct dcssblk_dev_info *dev_info;
+
+ for (i = 0; (i < DCSSBLK_PARM_LEN) && (dcssblk_segments[i] != '\0');
+ i++) {
+ for (j = i; (dcssblk_segments[j] != ',') &&
+ (dcssblk_segments[j] != '\0') &&
+ (dcssblk_segments[j] != '(') &&
+ (j - i) < 8; j++)
+ {
+ buf[j-i] = dcssblk_segments[j];
+ }
+ buf[j-i] = '\0';
+ rc = dcssblk_add_store(dcssblk_root_dev, buf, j-i);
+ if ((rc >= 0) && (dcssblk_segments[j] == '(')) {
+ for (k = 0; buf[k] != '\0'; k++)
+ buf[k] = toupper(buf[k]);
+ if (!strncmp(&dcssblk_segments[j], "(local)", 7)) {
+ down_read(&dcssblk_devices_sem);
+ dev_info = dcssblk_get_device_by_name(buf);
+ up_read(&dcssblk_devices_sem);
+ if (dev_info)
+ dcssblk_shared_store(&dev_info->dev,
+ "0\n", 2);
+ }
+ }
+ while ((dcssblk_segments[j] != ',') &&
+ (dcssblk_segments[j] != '\0'))
+ {
+ j++;
+ }
+ if (dcssblk_segments[j] == '\0')
+ break;
+ i = j;
+ }
+}
+
+/*
+ * The init/exit functions.
+ */
+static void __exit
+dcssblk_exit(void)
+{
+ int rc;
+
+ PRINT_DEBUG("DCSSBLOCK EXIT...\n");
+ s390_root_dev_unregister(dcssblk_root_dev);
+ rc = unregister_blkdev(dcssblk_major, DCSSBLK_NAME);
+ if (rc) {
+ PRINT_ERR("unregister_blkdev() failed!\n");
+ }
+ PRINT_DEBUG("...finished!\n");
+}
+
+static int __init
+dcssblk_init(void)
+{
+ int rc;
+
+ PRINT_DEBUG("DCSSBLOCK INIT...\n");
+ dcssblk_root_dev = s390_root_dev_register("dcssblk");
+ if (IS_ERR(dcssblk_root_dev)) {
+ PRINT_ERR("device_register() failed!\n");
+ return PTR_ERR(dcssblk_root_dev);
+ }
+ rc = device_create_file(dcssblk_root_dev, &dev_attr_add);
+ if (rc) {
+ PRINT_ERR("device_create_file(add) failed!\n");
+ s390_root_dev_unregister(dcssblk_root_dev);
+ return rc;
+ }
+ rc = device_create_file(dcssblk_root_dev, &dev_attr_remove);
+ if (rc) {
+ PRINT_ERR("device_create_file(remove) failed!\n");
+ s390_root_dev_unregister(dcssblk_root_dev);
+ return rc;
+ }
+ rc = register_blkdev(0, DCSSBLK_NAME);
+ if (rc < 0) {
+ PRINT_ERR("Can't get dynamic major!\n");
+ s390_root_dev_unregister(dcssblk_root_dev);
+ return rc;
+ }
+ dcssblk_major = rc;
+ init_rwsem(&dcssblk_devices_sem);
+
+ dcssblk_check_params();
+
+ PRINT_DEBUG("...finished!\n");
+ return 0;
+}
+
+module_init(dcssblk_init);
+module_exit(dcssblk_exit);
+
+module_param_string(segments, dcssblk_segments, DCSSBLK_PARM_LEN, 0444);
+MODULE_PARM_DESC(segments, "Name of DCSS segment(s) to be loaded, "
+ "comma-separated list, each name max. 8 chars.\n"
+ "Adding \"(local)\" to segment name equals echoing 0 to "
+ "/sys/devices/dcssblk/<segment name>/shared after loading "
+ "the segment - \n"
+ "e.g. segments=\"mydcss1,mydcss2,mydcss3(local)\"");
+
+MODULE_LICENSE("GPL");