linux/drivers/s390/char/vmlogrdr.c
Greg Kroah-Hartman 6f05e69e44 s390: char: add SPDX identifiers to the remaining files
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/s390/char/ files with the correct SPDX license
identifier based on the license text in the file itself.  The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-24 14:28:42 +01:00

903 lines
22 KiB
C

// 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);