This commit was manufactured by cvs2svn to create branch 'vserver'.
[linux-2.6.git] / drivers / s390 / char / monwriter.c
diff --git a/drivers/s390/char/monwriter.c b/drivers/s390/char/monwriter.c
new file mode 100644 (file)
index 0000000..cdb24f5
--- /dev/null
@@ -0,0 +1,298 @@
+/*
+ * 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   4010
+
+static int mon_max_bufs = 255;
+static int mon_buf_count;
+
+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;
+};
+
+/*
+ * 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.mon_function == monhdr->mon_function ||
+                    monhdr->mon_function == MONWRITE_STOP_INTERVAL) &&
+                   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 = NULL;
+       if (monhdr->mon_function != MONWRITE_GEN_EVENT)
+               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);
+                       mon_buf_count--;
+                       kfree(monbuf->data);
+                       kfree(monbuf);
+                       monbuf = NULL;
+               }
+       } else if (monhdr->mon_function != MONWRITE_STOP_INTERVAL) {
+               if (mon_buf_count >= mon_max_bufs)
+                       return -ENOSPC;
+               monbuf = kzalloc(sizeof(struct mon_buf), GFP_KERNEL);
+               if (!monbuf)
+                       return -ENOMEM;
+               monbuf->data = kzalloc(monhdr->datalen,
+                                      GFP_KERNEL | GFP_DMA);
+               if (!monbuf->data) {
+                       kfree(monbuf);
+                       return -ENOMEM;
+               }
+               monbuf->hdr = *monhdr;
+               list_add_tail(&monbuf->list, &monpriv->list);
+               if (monhdr->mon_function != MONWRITE_GEN_EVENT)
+                       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);
+               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");