[S390] Linux API for writing z/VM APPLDATA Monitor records.
authorMelissa Howland <melissah@us.ibm.com>
Wed, 20 Sep 2006 13:59:34 +0000 (15:59 +0200)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Wed, 20 Sep 2006 13:59:34 +0000 (15:59 +0200)
This patch delivers a new Linux API in the form of a misc char
device that is useable from user space and allows write access
to the z/VM APPLDATA Monitor Records collected by the *MONITOR
System Service of z/VM.

Signed-off-by: Melissa Howland <melissah@us.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch/s390/defconfig
drivers/s390/Kconfig
drivers/s390/char/Makefile
drivers/s390/char/monwriter.c [new file with mode: 0644]
include/asm-s390/Kbuild
include/asm-s390/monwriter.h [new file with mode: 0644]

index f1d4591eddbbd3bcf26801a728e033992841f412..35da53986b1b8ae696efc58f8be0024f9812eb2d 100644 (file)
@@ -428,6 +428,7 @@ CONFIG_S390_TAPE_34XX=m
 # CONFIG_VMLOGRDR is not set
 # CONFIG_VMCP is not set
 # CONFIG_MONREADER is not set
+CONFIG_MONWRITER=m
 
 #
 # Cryptographic devices
index bc4261e8b60607e8c974cace8fa7dc5924b62bf0..ae89b9b88743462538ba6069b268a13642530045 100644 (file)
@@ -213,6 +213,12 @@ config MONREADER
        help
          Character device driver for reading z/VM monitor service records
 
+config MONWRITER
+       tristate "API for writing z/VM monitor service records"
+       default "m"
+       help
+         Character device driver for writing z/VM monitor service records
+
 endmenu
 
 menu "Cryptographic devices"
index 0c0162ff6c0c003e6ec393c8686b3ba8fb98bf3d..c3e97b4fc18605e96767110a90644fdc3a4e02ca 100644 (file)
@@ -28,3 +28,4 @@ obj-$(CONFIG_S390_TAPE) += tape.o tape_class.o
 obj-$(CONFIG_S390_TAPE_34XX) += tape_34xx.o
 obj-$(CONFIG_S390_TAPE_3590) += tape_3590.o
 obj-$(CONFIG_MONREADER) += monreader.o
+obj-$(CONFIG_MONWRITER) += monwriter.o
diff --git a/drivers/s390/char/monwriter.c b/drivers/s390/char/monwriter.c
new file mode 100644 (file)
index 0000000..1e3939a
--- /dev/null
@@ -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");
index ed8955f49e47657a418f5c690644910b656a299e..979145026a2933421f830da8a0e262d69edc230d 100644 (file)
@@ -1,4 +1,4 @@
 include include/asm-generic/Kbuild.asm
 
 unifdef-y += cmb.h debug.h
-header-y += dasd.h qeth.h tape390.h ucontext.h vtoc.h z90crypt.h
+header-y += dasd.h monwriter.h qeth.h tape390.h ucontext.h vtoc.h z90crypt.h
diff --git a/include/asm-s390/monwriter.h b/include/asm-s390/monwriter.h
new file mode 100644 (file)
index 0000000..f0cbf96
--- /dev/null
@@ -0,0 +1,33 @@
+/*
+ * include/asm-s390/monwriter.h
+ *
+ * Copyright (C) IBM Corp. 2006
+ * Character device driver for writing z/VM APPLDATA monitor records
+ * Version 1.0
+ * Author(s): Melissa Howland <melissah@us.ibm.com>
+ *
+ */
+
+#ifndef _ASM_390_MONWRITER_H
+#define _ASM_390_MONWRITER_H
+
+/* mon_function values */
+#define MONWRITE_START_INTERVAL        0x00 /* start interval recording */
+#define MONWRITE_STOP_INTERVAL 0x01 /* stop interval or config recording */
+#define MONWRITE_GEN_EVENT     0x02 /* generate event record */
+#define MONWRITE_START_CONFIG  0x03 /* start configuration recording */
+
+/* the header the app uses in its write() data */
+struct monwrite_hdr {
+       unsigned char mon_function;
+       unsigned short applid;
+       unsigned char record_num;
+       unsigned short version;
+       unsigned short release;
+       unsigned short mod_level;
+       unsigned short datalen;
+       unsigned char hdrlen;
+
+} __attribute__((packed));
+
+#endif /* _ASM_390_MONWRITER_H */