v4.19.13 snapshot.
diff --git a/drivers/s390/char/vmlogrdr.c b/drivers/s390/char/vmlogrdr.c
new file mode 100644
index 0000000..069b9ef
--- /dev/null
+++ b/drivers/s390/char/vmlogrdr.c
@@ -0,0 +1,902 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * character device driver for reading z/VM system service records
+ *
+ *
+ * Copyright IBM Corp. 2004, 2009
+ * character device driver for reading z/VM system service records,
+ * Version 1.0
+ * Author(s): Xenia Tkatschow <xenia@us.ibm.com>
+ * Stefan Weinhuber <wein@de.ibm.com>
+ *
+ */
+
+#define KMSG_COMPONENT "vmlogrdr"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/atomic.h>
+#include <linux/uaccess.h>
+#include <asm/cpcmd.h>
+#include <asm/debug.h>
+#include <asm/ebcdic.h>
+#include <net/iucv/iucv.h>
+#include <linux/kmod.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/string.h>
+
+MODULE_AUTHOR
+ ("(C) 2004 IBM Corporation by Xenia Tkatschow (xenia@us.ibm.com)\n"
+ " Stefan Weinhuber (wein@de.ibm.com)");
+MODULE_DESCRIPTION ("Character device driver for reading z/VM "
+ "system service records.");
+MODULE_LICENSE("GPL");
+
+
+/*
+ * The size of the buffer for iucv data transfer is one page,
+ * but in addition to the data we read from iucv we also
+ * place an integer and some characters into that buffer,
+ * so the maximum size for record data is a little less then
+ * one page.
+ */
+#define NET_BUFFER_SIZE (PAGE_SIZE - sizeof(int) - sizeof(FENCE))
+
+/*
+ * The elements that are concurrently accessed by bottom halves are
+ * connection_established, iucv_path_severed, local_interrupt_buffer
+ * and receive_ready. The first three can be protected by
+ * priv_lock. receive_ready is atomic, so it can be incremented and
+ * decremented without holding a lock.
+ * The variable dev_in_use needs to be protected by the lock, since
+ * it's a flag used by open to make sure that the device is opened only
+ * by one user at the same time.
+ */
+struct vmlogrdr_priv_t {
+ char system_service[8];
+ char internal_name[8];
+ char recording_name[8];
+ struct iucv_path *path;
+ int connection_established;
+ int iucv_path_severed;
+ struct iucv_message local_interrupt_buffer;
+ atomic_t receive_ready;
+ int minor_num;
+ char * buffer;
+ char * current_position;
+ int remaining;
+ ulong residual_length;
+ int buffer_free;
+ int dev_in_use; /* 1: already opened, 0: not opened*/
+ spinlock_t priv_lock;
+ struct device *device;
+ struct device *class_device;
+ int autorecording;
+ int autopurge;
+};
+
+
+/*
+ * File operation structure for vmlogrdr devices
+ */
+static int vmlogrdr_open(struct inode *, struct file *);
+static int vmlogrdr_release(struct inode *, struct file *);
+static ssize_t vmlogrdr_read (struct file *filp, char __user *data,
+ size_t count, loff_t * ppos);
+
+static const struct file_operations vmlogrdr_fops = {
+ .owner = THIS_MODULE,
+ .open = vmlogrdr_open,
+ .release = vmlogrdr_release,
+ .read = vmlogrdr_read,
+ .llseek = no_llseek,
+};
+
+
+static void vmlogrdr_iucv_path_complete(struct iucv_path *, u8 *ipuser);
+static void vmlogrdr_iucv_path_severed(struct iucv_path *, u8 *ipuser);
+static void vmlogrdr_iucv_message_pending(struct iucv_path *,
+ struct iucv_message *);
+
+
+static struct iucv_handler vmlogrdr_iucv_handler = {
+ .path_complete = vmlogrdr_iucv_path_complete,
+ .path_severed = vmlogrdr_iucv_path_severed,
+ .message_pending = vmlogrdr_iucv_message_pending,
+};
+
+
+static DECLARE_WAIT_QUEUE_HEAD(conn_wait_queue);
+static DECLARE_WAIT_QUEUE_HEAD(read_wait_queue);
+
+/*
+ * pointer to system service private structure
+ * minor number 0 --> logrec
+ * minor number 1 --> account
+ * minor number 2 --> symptom
+ */
+
+static struct vmlogrdr_priv_t sys_ser[] = {
+ { .system_service = "*LOGREC ",
+ .internal_name = "logrec",
+ .recording_name = "EREP",
+ .minor_num = 0,
+ .buffer_free = 1,
+ .priv_lock = __SPIN_LOCK_UNLOCKED(sys_ser[0].priv_lock),
+ .autorecording = 1,
+ .autopurge = 1,
+ },
+ { .system_service = "*ACCOUNT",
+ .internal_name = "account",
+ .recording_name = "ACCOUNT",
+ .minor_num = 1,
+ .buffer_free = 1,
+ .priv_lock = __SPIN_LOCK_UNLOCKED(sys_ser[1].priv_lock),
+ .autorecording = 1,
+ .autopurge = 1,
+ },
+ { .system_service = "*SYMPTOM",
+ .internal_name = "symptom",
+ .recording_name = "SYMPTOM",
+ .minor_num = 2,
+ .buffer_free = 1,
+ .priv_lock = __SPIN_LOCK_UNLOCKED(sys_ser[2].priv_lock),
+ .autorecording = 1,
+ .autopurge = 1,
+ }
+};
+
+#define MAXMINOR (sizeof(sys_ser)/sizeof(struct vmlogrdr_priv_t))
+
+static char FENCE[] = {"EOR"};
+static int vmlogrdr_major = 0;
+static struct cdev *vmlogrdr_cdev = NULL;
+static int recording_class_AB;
+
+
+static void vmlogrdr_iucv_path_complete(struct iucv_path *path, u8 *ipuser)
+{
+ struct vmlogrdr_priv_t * logptr = path->private;
+
+ spin_lock(&logptr->priv_lock);
+ logptr->connection_established = 1;
+ spin_unlock(&logptr->priv_lock);
+ wake_up(&conn_wait_queue);
+}
+
+
+static void vmlogrdr_iucv_path_severed(struct iucv_path *path, u8 *ipuser)
+{
+ struct vmlogrdr_priv_t * logptr = path->private;
+ u8 reason = (u8) ipuser[8];
+
+ pr_err("vmlogrdr: connection severed with reason %i\n", reason);
+
+ iucv_path_sever(path, NULL);
+ kfree(path);
+ logptr->path = NULL;
+
+ spin_lock(&logptr->priv_lock);
+ logptr->connection_established = 0;
+ logptr->iucv_path_severed = 1;
+ spin_unlock(&logptr->priv_lock);
+
+ wake_up(&conn_wait_queue);
+ /* just in case we're sleeping waiting for a record */
+ wake_up_interruptible(&read_wait_queue);
+}
+
+
+static void vmlogrdr_iucv_message_pending(struct iucv_path *path,
+ struct iucv_message *msg)
+{
+ struct vmlogrdr_priv_t * logptr = path->private;
+
+ /*
+ * This function is the bottom half so it should be quick.
+ * Copy the external interrupt data into our local eib and increment
+ * the usage count
+ */
+ spin_lock(&logptr->priv_lock);
+ memcpy(&logptr->local_interrupt_buffer, msg, sizeof(*msg));
+ atomic_inc(&logptr->receive_ready);
+ spin_unlock(&logptr->priv_lock);
+ wake_up_interruptible(&read_wait_queue);
+}
+
+
+static int vmlogrdr_get_recording_class_AB(void)
+{
+ static const char cp_command[] = "QUERY COMMAND RECORDING ";
+ char cp_response[80];
+ char *tail;
+ int len,i;
+
+ cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
+ len = strnlen(cp_response,sizeof(cp_response));
+ // now the parsing
+ tail=strnchr(cp_response,len,'=');
+ if (!tail)
+ return 0;
+ tail++;
+ if (!strncmp("ANY",tail,3))
+ return 1;
+ if (!strncmp("NONE",tail,4))
+ return 0;
+ /*
+ * expect comma separated list of classes here, if one of them
+ * is A or B return 1 otherwise 0
+ */
+ for (i=tail-cp_response; i<len; i++)
+ if ( cp_response[i]=='A' || cp_response[i]=='B' )
+ return 1;
+ return 0;
+}
+
+
+static int vmlogrdr_recording(struct vmlogrdr_priv_t * logptr,
+ int action, int purge)
+{
+
+ char cp_command[80];
+ char cp_response[160];
+ char *onoff, *qid_string;
+ int rc;
+
+ onoff = ((action == 1) ? "ON" : "OFF");
+ qid_string = ((recording_class_AB == 1) ? " QID * " : "");
+
+ /*
+ * The recording commands needs to be called with option QID
+ * for guests that have previlege classes A or B.
+ * Purging has to be done as separate step, because recording
+ * can't be switched on as long as records are on the queue.
+ * Doing both at the same time doesn't work.
+ */
+ if (purge && (action == 1)) {
+ memset(cp_command, 0x00, sizeof(cp_command));
+ memset(cp_response, 0x00, sizeof(cp_response));
+ snprintf(cp_command, sizeof(cp_command),
+ "RECORDING %s PURGE %s",
+ logptr->recording_name,
+ qid_string);
+ cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
+ }
+
+ memset(cp_command, 0x00, sizeof(cp_command));
+ memset(cp_response, 0x00, sizeof(cp_response));
+ snprintf(cp_command, sizeof(cp_command), "RECORDING %s %s %s",
+ logptr->recording_name,
+ onoff,
+ qid_string);
+ cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
+ /* The recording command will usually answer with 'Command complete'
+ * on success, but when the specific service was never connected
+ * before then there might be an additional informational message
+ * 'HCPCRC8072I Recording entry not found' before the
+ * 'Command complete'. So I use strstr rather then the strncmp.
+ */
+ if (strstr(cp_response,"Command complete"))
+ rc = 0;
+ else
+ rc = -EIO;
+ /*
+ * If we turn recording off, we have to purge any remaining records
+ * afterwards, as a large number of queued records may impact z/VM
+ * performance.
+ */
+ if (purge && (action == 0)) {
+ memset(cp_command, 0x00, sizeof(cp_command));
+ memset(cp_response, 0x00, sizeof(cp_response));
+ snprintf(cp_command, sizeof(cp_command),
+ "RECORDING %s PURGE %s",
+ logptr->recording_name,
+ qid_string);
+ cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
+ }
+
+ return rc;
+}
+
+
+static int vmlogrdr_open (struct inode *inode, struct file *filp)
+{
+ int dev_num = 0;
+ struct vmlogrdr_priv_t * logptr = NULL;
+ int connect_rc = 0;
+ int ret;
+
+ dev_num = iminor(inode);
+ if (dev_num >= MAXMINOR)
+ return -ENODEV;
+ logptr = &sys_ser[dev_num];
+
+ /*
+ * only allow for blocking reads to be open
+ */
+ if (filp->f_flags & O_NONBLOCK)
+ return -EOPNOTSUPP;
+
+ /* Besure this device hasn't already been opened */
+ spin_lock_bh(&logptr->priv_lock);
+ if (logptr->dev_in_use) {
+ spin_unlock_bh(&logptr->priv_lock);
+ return -EBUSY;
+ }
+ logptr->dev_in_use = 1;
+ logptr->connection_established = 0;
+ logptr->iucv_path_severed = 0;
+ atomic_set(&logptr->receive_ready, 0);
+ logptr->buffer_free = 1;
+ spin_unlock_bh(&logptr->priv_lock);
+
+ /* set the file options */
+ filp->private_data = logptr;
+
+ /* start recording for this service*/
+ if (logptr->autorecording) {
+ ret = vmlogrdr_recording(logptr,1,logptr->autopurge);
+ if (ret)
+ pr_warn("vmlogrdr: failed to start recording automatically\n");
+ }
+
+ /* create connection to the system service */
+ logptr->path = iucv_path_alloc(10, 0, GFP_KERNEL);
+ if (!logptr->path)
+ goto out_dev;
+ connect_rc = iucv_path_connect(logptr->path, &vmlogrdr_iucv_handler,
+ logptr->system_service, NULL, NULL,
+ logptr);
+ if (connect_rc) {
+ pr_err("vmlogrdr: iucv connection to %s "
+ "failed with rc %i \n",
+ logptr->system_service, connect_rc);
+ goto out_path;
+ }
+
+ /* We've issued the connect and now we must wait for a
+ * ConnectionComplete or ConnectinSevered Interrupt
+ * before we can continue to process.
+ */
+ wait_event(conn_wait_queue, (logptr->connection_established)
+ || (logptr->iucv_path_severed));
+ if (logptr->iucv_path_severed)
+ goto out_record;
+ nonseekable_open(inode, filp);
+ return 0;
+
+out_record:
+ if (logptr->autorecording)
+ vmlogrdr_recording(logptr,0,logptr->autopurge);
+out_path:
+ kfree(logptr->path); /* kfree(NULL) is ok. */
+ logptr->path = NULL;
+out_dev:
+ logptr->dev_in_use = 0;
+ return -EIO;
+}
+
+
+static int vmlogrdr_release (struct inode *inode, struct file *filp)
+{
+ int ret;
+
+ struct vmlogrdr_priv_t * logptr = filp->private_data;
+
+ iucv_path_sever(logptr->path, NULL);
+ kfree(logptr->path);
+ logptr->path = NULL;
+ if (logptr->autorecording) {
+ ret = vmlogrdr_recording(logptr,0,logptr->autopurge);
+ if (ret)
+ pr_warn("vmlogrdr: failed to stop recording automatically\n");
+ }
+ logptr->dev_in_use = 0;
+
+ return 0;
+}
+
+
+static int vmlogrdr_receive_data(struct vmlogrdr_priv_t *priv)
+{
+ int rc, *temp;
+ /* we need to keep track of two data sizes here:
+ * The number of bytes we need to receive from iucv and
+ * the total number of bytes we actually write into the buffer.
+ */
+ int user_data_count, iucv_data_count;
+ char * buffer;
+
+ if (atomic_read(&priv->receive_ready)) {
+ spin_lock_bh(&priv->priv_lock);
+ if (priv->residual_length){
+ /* receive second half of a record */
+ iucv_data_count = priv->residual_length;
+ user_data_count = 0;
+ buffer = priv->buffer;
+ } else {
+ /* receive a new record:
+ * We need to return the total length of the record
+ * + size of FENCE in the first 4 bytes of the buffer.
+ */
+ iucv_data_count = priv->local_interrupt_buffer.length;
+ user_data_count = sizeof(int);
+ temp = (int*)priv->buffer;
+ *temp= iucv_data_count + sizeof(FENCE);
+ buffer = priv->buffer + sizeof(int);
+ }
+ /*
+ * If the record is bigger than our buffer, we receive only
+ * a part of it. We can get the rest later.
+ */
+ if (iucv_data_count > NET_BUFFER_SIZE)
+ iucv_data_count = NET_BUFFER_SIZE;
+ rc = iucv_message_receive(priv->path,
+ &priv->local_interrupt_buffer,
+ 0, buffer, iucv_data_count,
+ &priv->residual_length);
+ spin_unlock_bh(&priv->priv_lock);
+ /* An rc of 5 indicates that the record was bigger than
+ * the buffer, which is OK for us. A 9 indicates that the
+ * record was purged befor we could receive it.
+ */
+ if (rc == 5)
+ rc = 0;
+ if (rc == 9)
+ atomic_set(&priv->receive_ready, 0);
+ } else {
+ rc = 1;
+ }
+ if (!rc) {
+ priv->buffer_free = 0;
+ user_data_count += iucv_data_count;
+ priv->current_position = priv->buffer;
+ if (priv->residual_length == 0){
+ /* the whole record has been captured,
+ * now add the fence */
+ atomic_dec(&priv->receive_ready);
+ buffer = priv->buffer + user_data_count;
+ memcpy(buffer, FENCE, sizeof(FENCE));
+ user_data_count += sizeof(FENCE);
+ }
+ priv->remaining = user_data_count;
+ }
+
+ return rc;
+}
+
+
+static ssize_t vmlogrdr_read(struct file *filp, char __user *data,
+ size_t count, loff_t * ppos)
+{
+ int rc;
+ struct vmlogrdr_priv_t * priv = filp->private_data;
+
+ while (priv->buffer_free) {
+ rc = vmlogrdr_receive_data(priv);
+ if (rc) {
+ rc = wait_event_interruptible(read_wait_queue,
+ atomic_read(&priv->receive_ready));
+ if (rc)
+ return rc;
+ }
+ }
+ /* copy only up to end of record */
+ if (count > priv->remaining)
+ count = priv->remaining;
+
+ if (copy_to_user(data, priv->current_position, count))
+ return -EFAULT;
+
+ *ppos += count;
+ priv->current_position += count;
+ priv->remaining -= count;
+
+ /* if all data has been transferred, set buffer free */
+ if (priv->remaining == 0)
+ priv->buffer_free = 1;
+
+ return count;
+}
+
+static ssize_t vmlogrdr_autopurge_store(struct device * dev,
+ struct device_attribute *attr,
+ const char * buf, size_t count)
+{
+ struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
+ ssize_t ret = count;
+
+ switch (buf[0]) {
+ case '0':
+ priv->autopurge=0;
+ break;
+ case '1':
+ priv->autopurge=1;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ return ret;
+}
+
+
+static ssize_t vmlogrdr_autopurge_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
+ return sprintf(buf, "%u\n", priv->autopurge);
+}
+
+
+static DEVICE_ATTR(autopurge, 0644, vmlogrdr_autopurge_show,
+ vmlogrdr_autopurge_store);
+
+
+static ssize_t vmlogrdr_purge_store(struct device * dev,
+ struct device_attribute *attr,
+ const char * buf, size_t count)
+{
+
+ char cp_command[80];
+ char cp_response[80];
+ struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
+
+ if (buf[0] != '1')
+ return -EINVAL;
+
+ memset(cp_command, 0x00, sizeof(cp_command));
+ memset(cp_response, 0x00, sizeof(cp_response));
+
+ /*
+ * The recording command needs to be called with option QID
+ * for guests that have previlege classes A or B.
+ * Other guests will not recognize the command and we have to
+ * issue the same command without the QID parameter.
+ */
+
+ if (recording_class_AB)
+ snprintf(cp_command, sizeof(cp_command),
+ "RECORDING %s PURGE QID * ",
+ priv->recording_name);
+ else
+ snprintf(cp_command, sizeof(cp_command),
+ "RECORDING %s PURGE ",
+ priv->recording_name);
+
+ cpcmd(cp_command, cp_response, sizeof(cp_response), NULL);
+
+ return count;
+}
+
+
+static DEVICE_ATTR(purge, 0200, NULL, vmlogrdr_purge_store);
+
+
+static ssize_t vmlogrdr_autorecording_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
+ ssize_t ret = count;
+
+ switch (buf[0]) {
+ case '0':
+ priv->autorecording=0;
+ break;
+ case '1':
+ priv->autorecording=1;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ return ret;
+}
+
+
+static ssize_t vmlogrdr_autorecording_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
+ return sprintf(buf, "%u\n", priv->autorecording);
+}
+
+
+static DEVICE_ATTR(autorecording, 0644, vmlogrdr_autorecording_show,
+ vmlogrdr_autorecording_store);
+
+
+static ssize_t vmlogrdr_recording_store(struct device * dev,
+ struct device_attribute *attr,
+ const char * buf, size_t count)
+{
+ struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
+ ssize_t ret;
+
+ switch (buf[0]) {
+ case '0':
+ ret = vmlogrdr_recording(priv,0,0);
+ break;
+ case '1':
+ ret = vmlogrdr_recording(priv,1,0);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ if (ret)
+ return ret;
+ else
+ return count;
+
+}
+
+
+static DEVICE_ATTR(recording, 0200, NULL, vmlogrdr_recording_store);
+
+
+static ssize_t recording_status_show(struct device_driver *driver, char *buf)
+{
+ static const char cp_command[] = "QUERY RECORDING ";
+ int len;
+
+ cpcmd(cp_command, buf, 4096, NULL);
+ len = strlen(buf);
+ return len;
+}
+static DRIVER_ATTR_RO(recording_status);
+static struct attribute *vmlogrdr_drv_attrs[] = {
+ &driver_attr_recording_status.attr,
+ NULL,
+};
+static struct attribute_group vmlogrdr_drv_attr_group = {
+ .attrs = vmlogrdr_drv_attrs,
+};
+static const struct attribute_group *vmlogrdr_drv_attr_groups[] = {
+ &vmlogrdr_drv_attr_group,
+ NULL,
+};
+
+static struct attribute *vmlogrdr_attrs[] = {
+ &dev_attr_autopurge.attr,
+ &dev_attr_purge.attr,
+ &dev_attr_autorecording.attr,
+ &dev_attr_recording.attr,
+ NULL,
+};
+static struct attribute_group vmlogrdr_attr_group = {
+ .attrs = vmlogrdr_attrs,
+};
+static const struct attribute_group *vmlogrdr_attr_groups[] = {
+ &vmlogrdr_attr_group,
+ NULL,
+};
+
+static int vmlogrdr_pm_prepare(struct device *dev)
+{
+ int rc;
+ struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
+
+ rc = 0;
+ if (priv) {
+ spin_lock_bh(&priv->priv_lock);
+ if (priv->dev_in_use)
+ rc = -EBUSY;
+ spin_unlock_bh(&priv->priv_lock);
+ }
+ if (rc)
+ pr_err("vmlogrdr: device %s is busy. Refuse to suspend.\n",
+ dev_name(dev));
+ return rc;
+}
+
+
+static const struct dev_pm_ops vmlogrdr_pm_ops = {
+ .prepare = vmlogrdr_pm_prepare,
+};
+
+static struct class *vmlogrdr_class;
+static struct device_driver vmlogrdr_driver = {
+ .name = "vmlogrdr",
+ .bus = &iucv_bus,
+ .pm = &vmlogrdr_pm_ops,
+ .groups = vmlogrdr_drv_attr_groups,
+};
+
+static int vmlogrdr_register_driver(void)
+{
+ int ret;
+
+ /* Register with iucv driver */
+ ret = iucv_register(&vmlogrdr_iucv_handler, 1);
+ if (ret)
+ goto out;
+
+ ret = driver_register(&vmlogrdr_driver);
+ if (ret)
+ goto out_iucv;
+
+ vmlogrdr_class = class_create(THIS_MODULE, "vmlogrdr");
+ if (IS_ERR(vmlogrdr_class)) {
+ ret = PTR_ERR(vmlogrdr_class);
+ vmlogrdr_class = NULL;
+ goto out_driver;
+ }
+ return 0;
+
+out_driver:
+ driver_unregister(&vmlogrdr_driver);
+out_iucv:
+ iucv_unregister(&vmlogrdr_iucv_handler, 1);
+out:
+ return ret;
+}
+
+
+static void vmlogrdr_unregister_driver(void)
+{
+ class_destroy(vmlogrdr_class);
+ vmlogrdr_class = NULL;
+ driver_unregister(&vmlogrdr_driver);
+ iucv_unregister(&vmlogrdr_iucv_handler, 1);
+}
+
+
+static int vmlogrdr_register_device(struct vmlogrdr_priv_t *priv)
+{
+ struct device *dev;
+ int ret;
+
+ dev = kzalloc(sizeof(struct device), GFP_KERNEL);
+ if (dev) {
+ dev_set_name(dev, "%s", priv->internal_name);
+ dev->bus = &iucv_bus;
+ dev->parent = iucv_root;
+ dev->driver = &vmlogrdr_driver;
+ dev->groups = vmlogrdr_attr_groups;
+ dev_set_drvdata(dev, priv);
+ /*
+ * The release function could be called after the
+ * module has been unloaded. It's _only_ task is to
+ * free the struct. Therefore, we specify kfree()
+ * directly here. (Probably a little bit obfuscating
+ * but legitime ...).
+ */
+ dev->release = (void (*)(struct device *))kfree;
+ } else
+ return -ENOMEM;
+ ret = device_register(dev);
+ if (ret) {
+ put_device(dev);
+ return ret;
+ }
+
+ priv->class_device = device_create(vmlogrdr_class, dev,
+ MKDEV(vmlogrdr_major,
+ priv->minor_num),
+ priv, "%s", dev_name(dev));
+ if (IS_ERR(priv->class_device)) {
+ ret = PTR_ERR(priv->class_device);
+ priv->class_device=NULL;
+ device_unregister(dev);
+ return ret;
+ }
+ priv->device = dev;
+ return 0;
+}
+
+
+static int vmlogrdr_unregister_device(struct vmlogrdr_priv_t *priv)
+{
+ device_destroy(vmlogrdr_class, MKDEV(vmlogrdr_major, priv->minor_num));
+ if (priv->device != NULL) {
+ device_unregister(priv->device);
+ priv->device=NULL;
+ }
+ return 0;
+}
+
+
+static int vmlogrdr_register_cdev(dev_t dev)
+{
+ int rc = 0;
+ vmlogrdr_cdev = cdev_alloc();
+ if (!vmlogrdr_cdev) {
+ return -ENOMEM;
+ }
+ vmlogrdr_cdev->owner = THIS_MODULE;
+ vmlogrdr_cdev->ops = &vmlogrdr_fops;
+ rc = cdev_add(vmlogrdr_cdev, dev, MAXMINOR);
+ if (!rc)
+ return 0;
+
+ // cleanup: cdev is not fully registered, no cdev_del here!
+ kobject_put(&vmlogrdr_cdev->kobj);
+ vmlogrdr_cdev=NULL;
+ return rc;
+}
+
+
+static void vmlogrdr_cleanup(void)
+{
+ int i;
+
+ if (vmlogrdr_cdev) {
+ cdev_del(vmlogrdr_cdev);
+ vmlogrdr_cdev=NULL;
+ }
+ for (i=0; i < MAXMINOR; ++i ) {
+ vmlogrdr_unregister_device(&sys_ser[i]);
+ free_page((unsigned long)sys_ser[i].buffer);
+ }
+ vmlogrdr_unregister_driver();
+ if (vmlogrdr_major) {
+ unregister_chrdev_region(MKDEV(vmlogrdr_major, 0), MAXMINOR);
+ vmlogrdr_major=0;
+ }
+}
+
+
+static int __init vmlogrdr_init(void)
+{
+ int rc;
+ int i;
+ dev_t dev;
+
+ if (! MACHINE_IS_VM) {
+ pr_err("not running under VM, driver not loaded.\n");
+ return -ENODEV;
+ }
+
+ recording_class_AB = vmlogrdr_get_recording_class_AB();
+
+ rc = alloc_chrdev_region(&dev, 0, MAXMINOR, "vmlogrdr");
+ if (rc)
+ return rc;
+ vmlogrdr_major = MAJOR(dev);
+
+ rc=vmlogrdr_register_driver();
+ if (rc)
+ goto cleanup;
+
+ for (i=0; i < MAXMINOR; ++i ) {
+ sys_ser[i].buffer = (char *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ if (!sys_ser[i].buffer) {
+ rc = -ENOMEM;
+ break;
+ }
+ sys_ser[i].current_position = sys_ser[i].buffer;
+ rc=vmlogrdr_register_device(&sys_ser[i]);
+ if (rc)
+ break;
+ }
+ if (rc)
+ goto cleanup;
+
+ rc = vmlogrdr_register_cdev(dev);
+ if (rc)
+ goto cleanup;
+ return 0;
+
+cleanup:
+ vmlogrdr_cleanup();
+ return rc;
+}
+
+
+static void __exit vmlogrdr_exit(void)
+{
+ vmlogrdr_cleanup();
+ return;
+}
+
+
+module_init(vmlogrdr_init);
+module_exit(vmlogrdr_exit);