summaryrefslogtreecommitdiffstats
path: root/drivers/s390/char/monwriter.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/s390/char/monwriter.c')
-rw-r--r--drivers/s390/char/monwriter.c292
1 files changed, 292 insertions, 0 deletions
diff --git a/drivers/s390/char/monwriter.c b/drivers/s390/char/monwriter.c
new file mode 100644
index 000000000000..1e3939aeb8ab
--- /dev/null
+++ b/drivers/s390/char/monwriter.c
@@ -0,0 +1,292 @@
+/*
+ * drivers/s390/char/monwriter.c
+ *
+ * Character device driver for writing z/VM *MONITOR service records.
+ *
+ * Copyright (C) IBM Corp. 2006
+ *
+ * Author(s): Melissa Howland <Melissa.Howland@us.ibm.com>
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/ctype.h>
+#include <linux/poll.h>
+#include <asm/uaccess.h>
+#include <asm/ebcdic.h>
+#include <asm/io.h>
+#include <asm/appldata.h>
+#include <asm/monwriter.h>
+
+#define MONWRITE_MAX_DATALEN 4024
+
+static int mon_max_bufs = 255;
+
+struct mon_buf {
+ struct list_head list;
+ struct monwrite_hdr hdr;
+ int diag_done;
+ char *data;
+};
+
+struct mon_private {
+ struct list_head list;
+ struct monwrite_hdr hdr;
+ size_t hdr_to_read;
+ size_t data_to_read;
+ struct mon_buf *current_buf;
+ int mon_buf_count;
+};
+
+/*
+ * helper functions
+ */
+
+static int monwrite_diag(struct monwrite_hdr *myhdr, char *buffer, int fcn)
+{
+ struct appldata_product_id id;
+ int rc;
+
+ strcpy(id.prod_nr, "LNXAPPL");
+ id.prod_fn = myhdr->applid;
+ id.record_nr = myhdr->record_num;
+ id.version_nr = myhdr->version;
+ id.release_nr = myhdr->release;
+ id.mod_lvl = myhdr->mod_level;
+ rc = appldata_asm(&id, fcn, (void *) buffer, myhdr->datalen);
+ if (rc <= 0)
+ return rc;
+ if (rc == 5)
+ return -EPERM;
+ printk("DIAG X'DC' error with return code: %i\n", rc);
+ return -EINVAL;
+}
+
+static inline struct mon_buf *monwrite_find_hdr(struct mon_private *monpriv,
+ struct monwrite_hdr *monhdr)
+{
+ struct mon_buf *entry, *next;
+
+ list_for_each_entry_safe(entry, next, &monpriv->list, list)
+ if (entry->hdr.applid == monhdr->applid &&
+ entry->hdr.record_num == monhdr->record_num &&
+ entry->hdr.version == monhdr->version &&
+ entry->hdr.release == monhdr->release &&
+ entry->hdr.mod_level == monhdr->mod_level)
+ return entry;
+ return NULL;
+}
+
+static int monwrite_new_hdr(struct mon_private *monpriv)
+{
+ struct monwrite_hdr *monhdr = &monpriv->hdr;
+ struct mon_buf *monbuf;
+ int rc;
+
+ if (monhdr->datalen > MONWRITE_MAX_DATALEN ||
+ monhdr->mon_function > MONWRITE_START_CONFIG ||
+ monhdr->hdrlen != sizeof(struct monwrite_hdr))
+ return -EINVAL;
+ monbuf = monwrite_find_hdr(monpriv, monhdr);
+ if (monbuf) {
+ if (monhdr->mon_function == MONWRITE_STOP_INTERVAL) {
+ monhdr->datalen = monbuf->hdr.datalen;
+ rc = monwrite_diag(monhdr, monbuf->data,
+ APPLDATA_STOP_REC);
+ list_del(&monbuf->list);
+ monpriv->mon_buf_count--;
+ kfree(monbuf->data);
+ kfree(monbuf);
+ monbuf = NULL;
+ }
+ } else {
+ if (monpriv->mon_buf_count >= mon_max_bufs)
+ return -ENOSPC;
+ monbuf = kzalloc(sizeof(struct mon_buf), GFP_KERNEL);
+ if (!monbuf)
+ return -ENOMEM;
+ monbuf->data = kzalloc(monbuf->hdr.datalen,
+ GFP_KERNEL | GFP_DMA);
+ if (!monbuf->data) {
+ kfree(monbuf);
+ return -ENOMEM;
+ }
+ monbuf->hdr = *monhdr;
+ list_add_tail(&monbuf->list, &monpriv->list);
+ monpriv->mon_buf_count++;
+ }
+ monpriv->current_buf = monbuf;
+ return 0;
+}
+
+static int monwrite_new_data(struct mon_private *monpriv)
+{
+ struct monwrite_hdr *monhdr = &monpriv->hdr;
+ struct mon_buf *monbuf = monpriv->current_buf;
+ int rc = 0;
+
+ switch (monhdr->mon_function) {
+ case MONWRITE_START_INTERVAL:
+ if (!monbuf->diag_done) {
+ rc = monwrite_diag(monhdr, monbuf->data,
+ APPLDATA_START_INTERVAL_REC);
+ monbuf->diag_done = 1;
+ }
+ break;
+ case MONWRITE_START_CONFIG:
+ if (!monbuf->diag_done) {
+ rc = monwrite_diag(monhdr, monbuf->data,
+ APPLDATA_START_CONFIG_REC);
+ monbuf->diag_done = 1;
+ }
+ break;
+ case MONWRITE_GEN_EVENT:
+ rc = monwrite_diag(monhdr, monbuf->data,
+ APPLDATA_GEN_EVENT_REC);
+ list_del(&monpriv->current_buf->list);
+ kfree(monpriv->current_buf->data);
+ kfree(monpriv->current_buf);
+ monpriv->current_buf = NULL;
+ break;
+ default:
+ /* monhdr->mon_function is checked in monwrite_new_hdr */
+ BUG();
+ }
+ return rc;
+}
+
+/*
+ * file operations
+ */
+
+static int monwrite_open(struct inode *inode, struct file *filp)
+{
+ struct mon_private *monpriv;
+
+ monpriv = kzalloc(sizeof(struct mon_private), GFP_KERNEL);
+ if (!monpriv)
+ return -ENOMEM;
+ INIT_LIST_HEAD(&monpriv->list);
+ monpriv->hdr_to_read = sizeof(monpriv->hdr);
+ filp->private_data = monpriv;
+ return nonseekable_open(inode, filp);
+}
+
+static int monwrite_close(struct inode *inode, struct file *filp)
+{
+ struct mon_private *monpriv = filp->private_data;
+ struct mon_buf *entry, *next;
+
+ list_for_each_entry_safe(entry, next, &monpriv->list, list) {
+ if (entry->hdr.mon_function != MONWRITE_GEN_EVENT)
+ monwrite_diag(&entry->hdr, entry->data,
+ APPLDATA_STOP_REC);
+ monpriv->mon_buf_count--;
+ list_del(&entry->list);
+ kfree(entry->data);
+ kfree(entry);
+ }
+ kfree(monpriv);
+ return 0;
+}
+
+static ssize_t monwrite_write(struct file *filp, const char __user *data,
+ size_t count, loff_t *ppos)
+{
+ struct mon_private *monpriv = filp->private_data;
+ size_t len, written;
+ void *to;
+ int rc;
+
+ for (written = 0; written < count; ) {
+ if (monpriv->hdr_to_read) {
+ len = min(count - written, monpriv->hdr_to_read);
+ to = (char *) &monpriv->hdr +
+ sizeof(monpriv->hdr) - monpriv->hdr_to_read;
+ if (copy_from_user(to, data + written, len)) {
+ rc = -EFAULT;
+ goto out_error;
+ }
+ monpriv->hdr_to_read -= len;
+ written += len;
+ if (monpriv->hdr_to_read > 0)
+ continue;
+ rc = monwrite_new_hdr(monpriv);
+ if (rc)
+ goto out_error;
+ monpriv->data_to_read = monpriv->current_buf ?
+ monpriv->current_buf->hdr.datalen : 0;
+ }
+
+ if (monpriv->data_to_read) {
+ len = min(count - written, monpriv->data_to_read);
+ to = monpriv->current_buf->data +
+ monpriv->hdr.datalen - monpriv->data_to_read;
+ if (copy_from_user(to, data + written, len)) {
+ rc = -EFAULT;
+ goto out_error;
+ }
+ monpriv->data_to_read -= len;
+ written += len;
+ if (monpriv->data_to_read > 0)
+ continue;
+ rc = monwrite_new_data(monpriv);
+ if (rc)
+ goto out_error;
+ }
+ monpriv->hdr_to_read = sizeof(monpriv->hdr);
+ }
+ return written;
+
+out_error:
+ monpriv->data_to_read = 0;
+ monpriv->hdr_to_read = sizeof(struct monwrite_hdr);
+ return rc;
+}
+
+static struct file_operations monwrite_fops = {
+ .owner = THIS_MODULE,
+ .open = &monwrite_open,
+ .release = &monwrite_close,
+ .write = &monwrite_write,
+};
+
+static struct miscdevice mon_dev = {
+ .name = "monwriter",
+ .fops = &monwrite_fops,
+ .minor = MISC_DYNAMIC_MINOR,
+};
+
+/*
+ * module init/exit
+ */
+
+static int __init mon_init(void)
+{
+ if (MACHINE_IS_VM)
+ return misc_register(&mon_dev);
+ else
+ return -ENODEV;
+}
+
+static void __exit mon_exit(void)
+{
+ WARN_ON(misc_deregister(&mon_dev) != 0);
+}
+
+module_init(mon_init);
+module_exit(mon_exit);
+
+module_param_named(max_bufs, mon_max_bufs, int, 0644);
+MODULE_PARM_DESC(max_bufs, "Maximum number of sample monitor data buffers"
+ "that can be active at one time");
+
+MODULE_AUTHOR("Melissa Howland <Melissa.Howland@us.ibm.com>");
+MODULE_DESCRIPTION("Character device driver for writing z/VM "
+ "APPLDATA monitor records.");
+MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud