| /* |
| * 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; |
| 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.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); |
| mon_buf_count--; |
| kfree(monbuf->data); |
| kfree(monbuf); |
| monbuf = NULL; |
| } |
| } else { |
| 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); |
| 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"); |