mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-22 20:23:57 +08:00
1da177e4c3
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!
776 lines
19 KiB
C
776 lines
19 KiB
C
/*
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* dcssblk.c -- the S/390 block driver for dcss memory
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*
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* Authors: Carsten Otte, Stefan Weinhuber, Gerald Schaefer
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*/
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/ctype.h>
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <asm/extmem.h>
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#include <asm/io.h>
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#include <linux/completion.h>
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#include <linux/interrupt.h>
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#include <asm/ccwdev.h> // for s390_root_dev_(un)register()
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//#define DCSSBLK_DEBUG /* Debug messages on/off */
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#define DCSSBLK_NAME "dcssblk"
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#define DCSSBLK_MINORS_PER_DISK 1
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#define DCSSBLK_PARM_LEN 400
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#ifdef DCSSBLK_DEBUG
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#define PRINT_DEBUG(x...) printk(KERN_DEBUG DCSSBLK_NAME " debug: " x)
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#else
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#define PRINT_DEBUG(x...) do {} while (0)
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#endif
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#define PRINT_INFO(x...) printk(KERN_INFO DCSSBLK_NAME " info: " x)
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#define PRINT_WARN(x...) printk(KERN_WARNING DCSSBLK_NAME " warning: " x)
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#define PRINT_ERR(x...) printk(KERN_ERR DCSSBLK_NAME " error: " x)
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static int dcssblk_open(struct inode *inode, struct file *filp);
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static int dcssblk_release(struct inode *inode, struct file *filp);
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static int dcssblk_make_request(struct request_queue *q, struct bio *bio);
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static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
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static int dcssblk_major;
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static struct block_device_operations dcssblk_devops = {
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.owner = THIS_MODULE,
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.open = dcssblk_open,
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.release = dcssblk_release,
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};
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static ssize_t dcssblk_add_store(struct device * dev, const char * buf,
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size_t count);
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static ssize_t dcssblk_remove_store(struct device * dev, const char * buf,
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size_t count);
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static ssize_t dcssblk_save_store(struct device * dev, const char * buf,
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size_t count);
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static ssize_t dcssblk_save_show(struct device *dev, char *buf);
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static ssize_t dcssblk_shared_store(struct device * dev, const char * buf,
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size_t count);
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static ssize_t dcssblk_shared_show(struct device *dev, char *buf);
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static DEVICE_ATTR(add, S_IWUSR, NULL, dcssblk_add_store);
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static DEVICE_ATTR(remove, S_IWUSR, NULL, dcssblk_remove_store);
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static DEVICE_ATTR(save, S_IWUSR | S_IRUGO, dcssblk_save_show,
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dcssblk_save_store);
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static DEVICE_ATTR(shared, S_IWUSR | S_IRUGO, dcssblk_shared_show,
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dcssblk_shared_store);
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static struct device *dcssblk_root_dev;
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struct dcssblk_dev_info {
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struct list_head lh;
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struct device dev;
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char segment_name[BUS_ID_SIZE];
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atomic_t use_count;
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struct gendisk *gd;
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unsigned long start;
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unsigned long end;
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int segment_type;
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unsigned char save_pending;
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unsigned char is_shared;
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struct request_queue *dcssblk_queue;
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};
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static struct list_head dcssblk_devices = LIST_HEAD_INIT(dcssblk_devices);
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static struct rw_semaphore dcssblk_devices_sem;
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/*
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* release function for segment device.
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*/
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static void
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dcssblk_release_segment(struct device *dev)
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{
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PRINT_DEBUG("segment release fn called for %s\n", dev->bus_id);
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kfree(container_of(dev, struct dcssblk_dev_info, dev));
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module_put(THIS_MODULE);
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}
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/*
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* get a minor number. needs to be called with
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* down_write(&dcssblk_devices_sem) and the
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* device needs to be enqueued before the semaphore is
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* freed.
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*/
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static inline int
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dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info)
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{
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int minor, found;
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struct dcssblk_dev_info *entry;
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if (dev_info == NULL)
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return -EINVAL;
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for (minor = 0; minor < (1<<MINORBITS); minor++) {
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found = 0;
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// test if minor available
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list_for_each_entry(entry, &dcssblk_devices, lh)
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if (minor == entry->gd->first_minor)
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found++;
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if (!found) break; // got unused minor
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}
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if (found)
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return -EBUSY;
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dev_info->gd->first_minor = minor;
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return 0;
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}
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/*
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* get the struct dcssblk_dev_info from dcssblk_devices
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* for the given name.
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* down_read(&dcssblk_devices_sem) must be held.
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*/
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static struct dcssblk_dev_info *
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dcssblk_get_device_by_name(char *name)
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{
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struct dcssblk_dev_info *entry;
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list_for_each_entry(entry, &dcssblk_devices, lh) {
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if (!strcmp(name, entry->segment_name)) {
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return entry;
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}
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}
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return NULL;
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}
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/*
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* print appropriate error message for segment_load()/segment_type()
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* return code
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*/
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static void
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dcssblk_segment_warn(int rc, char* seg_name)
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{
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switch (rc) {
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case -ENOENT:
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PRINT_WARN("cannot load/query segment %s, does not exist\n",
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seg_name);
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break;
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case -ENOSYS:
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PRINT_WARN("cannot load/query segment %s, not running on VM\n",
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seg_name);
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break;
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case -EIO:
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PRINT_WARN("cannot load/query segment %s, hardware error\n",
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seg_name);
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break;
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case -ENOTSUPP:
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PRINT_WARN("cannot load/query segment %s, is a multi-part "
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"segment\n", seg_name);
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break;
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case -ENOSPC:
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PRINT_WARN("cannot load/query segment %s, overlaps with "
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"storage\n", seg_name);
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break;
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case -EBUSY:
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PRINT_WARN("cannot load/query segment %s, overlaps with "
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"already loaded dcss\n", seg_name);
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break;
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case -EPERM:
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PRINT_WARN("cannot load/query segment %s, already loaded in "
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"incompatible mode\n", seg_name);
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break;
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case -ENOMEM:
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PRINT_WARN("cannot load/query segment %s, out of memory\n",
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seg_name);
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break;
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case -ERANGE:
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PRINT_WARN("cannot load/query segment %s, exceeds kernel "
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"mapping range\n", seg_name);
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break;
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default:
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PRINT_WARN("cannot load/query segment %s, return value %i\n",
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seg_name, rc);
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break;
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}
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}
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/*
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* device attribute for switching shared/nonshared (exclusive)
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* operation (show + store)
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*/
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static ssize_t
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dcssblk_shared_show(struct device *dev, char *buf)
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{
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struct dcssblk_dev_info *dev_info;
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dev_info = container_of(dev, struct dcssblk_dev_info, dev);
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return sprintf(buf, dev_info->is_shared ? "1\n" : "0\n");
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}
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static ssize_t
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dcssblk_shared_store(struct device *dev, const char *inbuf, size_t count)
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{
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struct dcssblk_dev_info *dev_info;
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int rc;
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if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) {
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PRINT_WARN("Invalid value, must be 0 or 1\n");
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return -EINVAL;
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}
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down_write(&dcssblk_devices_sem);
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dev_info = container_of(dev, struct dcssblk_dev_info, dev);
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if (atomic_read(&dev_info->use_count)) {
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PRINT_ERR("share: segment %s is busy!\n",
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dev_info->segment_name);
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rc = -EBUSY;
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goto out;
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}
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if (inbuf[0] == '1') {
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// reload segment in shared mode
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rc = segment_modify_shared(dev_info->segment_name,
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SEGMENT_SHARED);
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if (rc < 0) {
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BUG_ON(rc == -EINVAL);
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if (rc == -EIO || rc == -ENOENT)
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goto removeseg;
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} else {
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dev_info->is_shared = 1;
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switch (dev_info->segment_type) {
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case SEG_TYPE_SR:
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case SEG_TYPE_ER:
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case SEG_TYPE_SC:
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set_disk_ro(dev_info->gd,1);
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}
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}
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} else if (inbuf[0] == '0') {
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// reload segment in exclusive mode
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if (dev_info->segment_type == SEG_TYPE_SC) {
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PRINT_ERR("Segment type SC (%s) cannot be loaded in "
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"non-shared mode\n", dev_info->segment_name);
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rc = -EINVAL;
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goto out;
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}
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rc = segment_modify_shared(dev_info->segment_name,
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SEGMENT_EXCLUSIVE);
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if (rc < 0) {
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BUG_ON(rc == -EINVAL);
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if (rc == -EIO || rc == -ENOENT)
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goto removeseg;
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} else {
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dev_info->is_shared = 0;
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set_disk_ro(dev_info->gd, 0);
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}
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} else {
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PRINT_WARN("Invalid value, must be 0 or 1\n");
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rc = -EINVAL;
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goto out;
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}
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rc = count;
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goto out;
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removeseg:
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PRINT_ERR("Could not reload segment %s, removing it now!\n",
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dev_info->segment_name);
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list_del(&dev_info->lh);
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del_gendisk(dev_info->gd);
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blk_put_queue(dev_info->dcssblk_queue);
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dev_info->gd->queue = NULL;
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put_disk(dev_info->gd);
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device_unregister(dev);
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put_device(dev);
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out:
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up_write(&dcssblk_devices_sem);
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return rc;
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}
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/*
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* device attribute for save operation on current copy
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* of the segment. If the segment is busy, saving will
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* become pending until it gets released, which can be
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* undone by storing a non-true value to this entry.
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* (show + store)
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*/
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static ssize_t
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dcssblk_save_show(struct device *dev, char *buf)
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{
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struct dcssblk_dev_info *dev_info;
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dev_info = container_of(dev, struct dcssblk_dev_info, dev);
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return sprintf(buf, dev_info->save_pending ? "1\n" : "0\n");
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}
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static ssize_t
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dcssblk_save_store(struct device *dev, const char *inbuf, size_t count)
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{
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struct dcssblk_dev_info *dev_info;
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if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) {
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PRINT_WARN("Invalid value, must be 0 or 1\n");
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return -EINVAL;
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}
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dev_info = container_of(dev, struct dcssblk_dev_info, dev);
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down_write(&dcssblk_devices_sem);
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if (inbuf[0] == '1') {
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if (atomic_read(&dev_info->use_count) == 0) {
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// device is idle => we save immediately
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PRINT_INFO("Saving segment %s\n",
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dev_info->segment_name);
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segment_save(dev_info->segment_name);
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} else {
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// device is busy => we save it when it becomes
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// idle in dcssblk_release
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PRINT_INFO("Segment %s is currently busy, it will "
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"be saved when it becomes idle...\n",
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dev_info->segment_name);
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dev_info->save_pending = 1;
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}
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} else if (inbuf[0] == '0') {
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if (dev_info->save_pending) {
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// device is busy & the user wants to undo his save
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// request
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dev_info->save_pending = 0;
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PRINT_INFO("Pending save for segment %s deactivated\n",
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dev_info->segment_name);
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}
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} else {
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up_write(&dcssblk_devices_sem);
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PRINT_WARN("Invalid value, must be 0 or 1\n");
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return -EINVAL;
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}
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up_write(&dcssblk_devices_sem);
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return count;
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}
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/*
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* device attribute for adding devices
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*/
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static ssize_t
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dcssblk_add_store(struct device *dev, const char *buf, size_t count)
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{
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int rc, i;
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struct dcssblk_dev_info *dev_info;
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char *local_buf;
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unsigned long seg_byte_size;
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dev_info = NULL;
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if (dev != dcssblk_root_dev) {
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rc = -EINVAL;
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goto out_nobuf;
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}
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local_buf = kmalloc(count + 1, GFP_KERNEL);
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if (local_buf == NULL) {
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rc = -ENOMEM;
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goto out_nobuf;
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}
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/*
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* parse input
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*/
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for (i = 0; ((buf[i] != '\0') && (buf[i] != '\n') && i < count); i++) {
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local_buf[i] = toupper(buf[i]);
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}
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local_buf[i] = '\0';
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if ((i == 0) || (i > 8)) {
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rc = -ENAMETOOLONG;
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goto out;
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}
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/*
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* already loaded?
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*/
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down_read(&dcssblk_devices_sem);
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dev_info = dcssblk_get_device_by_name(local_buf);
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up_read(&dcssblk_devices_sem);
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if (dev_info != NULL) {
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PRINT_WARN("Segment %s already loaded!\n", local_buf);
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rc = -EEXIST;
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goto out;
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}
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/*
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* get a struct dcssblk_dev_info
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*/
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dev_info = kmalloc(sizeof(struct dcssblk_dev_info), GFP_KERNEL);
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if (dev_info == NULL) {
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rc = -ENOMEM;
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goto out;
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}
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memset(dev_info, 0, sizeof(struct dcssblk_dev_info));
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strcpy(dev_info->segment_name, local_buf);
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strlcpy(dev_info->dev.bus_id, local_buf, BUS_ID_SIZE);
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dev_info->dev.release = dcssblk_release_segment;
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INIT_LIST_HEAD(&dev_info->lh);
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dev_info->gd = alloc_disk(DCSSBLK_MINORS_PER_DISK);
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if (dev_info->gd == NULL) {
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rc = -ENOMEM;
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goto free_dev_info;
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}
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dev_info->gd->major = dcssblk_major;
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dev_info->gd->fops = &dcssblk_devops;
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dev_info->dcssblk_queue = blk_alloc_queue(GFP_KERNEL);
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dev_info->gd->queue = dev_info->dcssblk_queue;
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dev_info->gd->private_data = dev_info;
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dev_info->gd->driverfs_dev = &dev_info->dev;
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/*
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* load the segment
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*/
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rc = segment_load(local_buf, SEGMENT_SHARED,
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&dev_info->start, &dev_info->end);
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if (rc < 0) {
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dcssblk_segment_warn(rc, dev_info->segment_name);
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goto dealloc_gendisk;
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}
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seg_byte_size = (dev_info->end - dev_info->start + 1);
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set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors
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PRINT_INFO("Loaded segment %s, size = %lu Byte, "
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"capacity = %lu (512 Byte) sectors\n", local_buf,
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seg_byte_size, seg_byte_size >> 9);
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dev_info->segment_type = rc;
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dev_info->save_pending = 0;
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dev_info->is_shared = 1;
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dev_info->dev.parent = dcssblk_root_dev;
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/*
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* get minor, add to list
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*/
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down_write(&dcssblk_devices_sem);
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rc = dcssblk_assign_free_minor(dev_info);
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if (rc) {
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up_write(&dcssblk_devices_sem);
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PRINT_ERR("No free minor number available! "
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"Unloading segment...\n");
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goto unload_seg;
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}
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sprintf(dev_info->gd->disk_name, "dcssblk%d",
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dev_info->gd->first_minor);
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list_add_tail(&dev_info->lh, &dcssblk_devices);
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if (!try_module_get(THIS_MODULE)) {
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rc = -ENODEV;
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goto list_del;
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}
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/*
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* register the device
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*/
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rc = device_register(&dev_info->dev);
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if (rc) {
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PRINT_ERR("Segment %s could not be registered RC=%d\n",
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local_buf, rc);
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module_put(THIS_MODULE);
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goto list_del;
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}
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get_device(&dev_info->dev);
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rc = device_create_file(&dev_info->dev, &dev_attr_shared);
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if (rc)
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goto unregister_dev;
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rc = device_create_file(&dev_info->dev, &dev_attr_save);
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if (rc)
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goto unregister_dev;
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add_disk(dev_info->gd);
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blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request);
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blk_queue_hardsect_size(dev_info->dcssblk_queue, 4096);
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switch (dev_info->segment_type) {
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case SEG_TYPE_SR:
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case SEG_TYPE_ER:
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case SEG_TYPE_SC:
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set_disk_ro(dev_info->gd,1);
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break;
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default:
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set_disk_ro(dev_info->gd,0);
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break;
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}
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PRINT_DEBUG("Segment %s loaded successfully\n", local_buf);
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up_write(&dcssblk_devices_sem);
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rc = count;
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goto out;
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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");
|