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11#define KMSG_COMPONENT "monwriter"
12#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14#include <linux/module.h>
15#include <linux/moduleparam.h>
16#include <linux/init.h>
17#include <linux/errno.h>
18#include <linux/smp_lock.h>
19#include <linux/types.h>
20#include <linux/kernel.h>
21#include <linux/miscdevice.h>
22#include <linux/ctype.h>
23#include <linux/poll.h>
24#include <linux/mutex.h>
25#include <asm/uaccess.h>
26#include <asm/ebcdic.h>
27#include <asm/io.h>
28#include <asm/appldata.h>
29#include <asm/monwriter.h>
30
31#define MONWRITE_MAX_DATALEN 4010
32
33static int mon_max_bufs = 255;
34static int mon_buf_count;
35
36struct mon_buf {
37 struct list_head list;
38 struct monwrite_hdr hdr;
39 int diag_done;
40 char *data;
41};
42
43struct mon_private {
44 struct list_head list;
45 struct monwrite_hdr hdr;
46 size_t hdr_to_read;
47 size_t data_to_read;
48 struct mon_buf *current_buf;
49 struct mutex thread_mutex;
50};
51
52
53
54
55
56static int monwrite_diag(struct monwrite_hdr *myhdr, char *buffer, int fcn)
57{
58 struct appldata_product_id id;
59 int rc;
60
61 strcpy(id.prod_nr, "LNXAPPL");
62 id.prod_fn = myhdr->applid;
63 id.record_nr = myhdr->record_num;
64 id.version_nr = myhdr->version;
65 id.release_nr = myhdr->release;
66 id.mod_lvl = myhdr->mod_level;
67 rc = appldata_asm(&id, fcn, (void *) buffer, myhdr->datalen);
68 if (rc <= 0)
69 return rc;
70 pr_err("Writing monitor data failed with rc=%i\n", rc);
71 if (rc == 5)
72 return -EPERM;
73 return -EINVAL;
74}
75
76static struct mon_buf *monwrite_find_hdr(struct mon_private *monpriv,
77 struct monwrite_hdr *monhdr)
78{
79 struct mon_buf *entry, *next;
80
81 list_for_each_entry_safe(entry, next, &monpriv->list, list)
82 if ((entry->hdr.mon_function == monhdr->mon_function ||
83 monhdr->mon_function == MONWRITE_STOP_INTERVAL) &&
84 entry->hdr.applid == monhdr->applid &&
85 entry->hdr.record_num == monhdr->record_num &&
86 entry->hdr.version == monhdr->version &&
87 entry->hdr.release == monhdr->release &&
88 entry->hdr.mod_level == monhdr->mod_level)
89 return entry;
90
91 return NULL;
92}
93
94static int monwrite_new_hdr(struct mon_private *monpriv)
95{
96 struct monwrite_hdr *monhdr = &monpriv->hdr;
97 struct mon_buf *monbuf;
98 int rc;
99
100 if (monhdr->datalen > MONWRITE_MAX_DATALEN ||
101 monhdr->mon_function > MONWRITE_START_CONFIG ||
102 monhdr->hdrlen != sizeof(struct monwrite_hdr))
103 return -EINVAL;
104 monbuf = NULL;
105 if (monhdr->mon_function != MONWRITE_GEN_EVENT)
106 monbuf = monwrite_find_hdr(monpriv, monhdr);
107 if (monbuf) {
108 if (monhdr->mon_function == MONWRITE_STOP_INTERVAL) {
109 monhdr->datalen = monbuf->hdr.datalen;
110 rc = monwrite_diag(monhdr, monbuf->data,
111 APPLDATA_STOP_REC);
112 list_del(&monbuf->list);
113 mon_buf_count--;
114 kfree(monbuf->data);
115 kfree(monbuf);
116 monbuf = NULL;
117 }
118 } else if (monhdr->mon_function != MONWRITE_STOP_INTERVAL) {
119 if (mon_buf_count >= mon_max_bufs)
120 return -ENOSPC;
121 monbuf = kzalloc(sizeof(struct mon_buf), GFP_KERNEL);
122 if (!monbuf)
123 return -ENOMEM;
124 monbuf->data = kzalloc(monhdr->datalen,
125 GFP_KERNEL | GFP_DMA);
126 if (!monbuf->data) {
127 kfree(monbuf);
128 return -ENOMEM;
129 }
130 monbuf->hdr = *monhdr;
131 list_add_tail(&monbuf->list, &monpriv->list);
132 if (monhdr->mon_function != MONWRITE_GEN_EVENT)
133 mon_buf_count++;
134 }
135 monpriv->current_buf = monbuf;
136 return 0;
137}
138
139static int monwrite_new_data(struct mon_private *monpriv)
140{
141 struct monwrite_hdr *monhdr = &monpriv->hdr;
142 struct mon_buf *monbuf = monpriv->current_buf;
143 int rc = 0;
144
145 switch (monhdr->mon_function) {
146 case MONWRITE_START_INTERVAL:
147 if (!monbuf->diag_done) {
148 rc = monwrite_diag(monhdr, monbuf->data,
149 APPLDATA_START_INTERVAL_REC);
150 monbuf->diag_done = 1;
151 }
152 break;
153 case MONWRITE_START_CONFIG:
154 if (!monbuf->diag_done) {
155 rc = monwrite_diag(monhdr, monbuf->data,
156 APPLDATA_START_CONFIG_REC);
157 monbuf->diag_done = 1;
158 }
159 break;
160 case MONWRITE_GEN_EVENT:
161 rc = monwrite_diag(monhdr, monbuf->data,
162 APPLDATA_GEN_EVENT_REC);
163 list_del(&monpriv->current_buf->list);
164 kfree(monpriv->current_buf->data);
165 kfree(monpriv->current_buf);
166 monpriv->current_buf = NULL;
167 break;
168 default:
169
170 BUG();
171 }
172 return rc;
173}
174
175
176
177
178
179static int monwrite_open(struct inode *inode, struct file *filp)
180{
181 struct mon_private *monpriv;
182
183 monpriv = kzalloc(sizeof(struct mon_private), GFP_KERNEL);
184 if (!monpriv)
185 return -ENOMEM;
186 lock_kernel();
187 INIT_LIST_HEAD(&monpriv->list);
188 monpriv->hdr_to_read = sizeof(monpriv->hdr);
189 mutex_init(&monpriv->thread_mutex);
190 filp->private_data = monpriv;
191 unlock_kernel();
192 return nonseekable_open(inode, filp);
193}
194
195static int monwrite_close(struct inode *inode, struct file *filp)
196{
197 struct mon_private *monpriv = filp->private_data;
198 struct mon_buf *entry, *next;
199
200 list_for_each_entry_safe(entry, next, &monpriv->list, list) {
201 if (entry->hdr.mon_function != MONWRITE_GEN_EVENT)
202 monwrite_diag(&entry->hdr, entry->data,
203 APPLDATA_STOP_REC);
204 mon_buf_count--;
205 list_del(&entry->list);
206 kfree(entry->data);
207 kfree(entry);
208 }
209 kfree(monpriv);
210 return 0;
211}
212
213static ssize_t monwrite_write(struct file *filp, const char __user *data,
214 size_t count, loff_t *ppos)
215{
216 struct mon_private *monpriv = filp->private_data;
217 size_t len, written;
218 void *to;
219 int rc;
220
221 mutex_lock(&monpriv->thread_mutex);
222 for (written = 0; written < count; ) {
223 if (monpriv->hdr_to_read) {
224 len = min(count - written, monpriv->hdr_to_read);
225 to = (char *) &monpriv->hdr +
226 sizeof(monpriv->hdr) - monpriv->hdr_to_read;
227 if (copy_from_user(to, data + written, len)) {
228 rc = -EFAULT;
229 goto out_error;
230 }
231 monpriv->hdr_to_read -= len;
232 written += len;
233 if (monpriv->hdr_to_read > 0)
234 continue;
235 rc = monwrite_new_hdr(monpriv);
236 if (rc)
237 goto out_error;
238 monpriv->data_to_read = monpriv->current_buf ?
239 monpriv->current_buf->hdr.datalen : 0;
240 }
241
242 if (monpriv->data_to_read) {
243 len = min(count - written, monpriv->data_to_read);
244 to = monpriv->current_buf->data +
245 monpriv->hdr.datalen - monpriv->data_to_read;
246 if (copy_from_user(to, data + written, len)) {
247 rc = -EFAULT;
248 goto out_error;
249 }
250 monpriv->data_to_read -= len;
251 written += len;
252 if (monpriv->data_to_read > 0)
253 continue;
254 rc = monwrite_new_data(monpriv);
255 if (rc)
256 goto out_error;
257 }
258 monpriv->hdr_to_read = sizeof(monpriv->hdr);
259 }
260 mutex_unlock(&monpriv->thread_mutex);
261 return written;
262
263out_error:
264 monpriv->data_to_read = 0;
265 monpriv->hdr_to_read = sizeof(struct monwrite_hdr);
266 mutex_unlock(&monpriv->thread_mutex);
267 return rc;
268}
269
270static const struct file_operations monwrite_fops = {
271 .owner = THIS_MODULE,
272 .open = &monwrite_open,
273 .release = &monwrite_close,
274 .write = &monwrite_write,
275};
276
277static struct miscdevice mon_dev = {
278 .name = "monwriter",
279 .fops = &monwrite_fops,
280 .minor = MISC_DYNAMIC_MINOR,
281};
282
283
284
285
286
287static int __init mon_init(void)
288{
289 if (MACHINE_IS_VM)
290 return misc_register(&mon_dev);
291 else
292 return -ENODEV;
293}
294
295static void __exit mon_exit(void)
296{
297 WARN_ON(misc_deregister(&mon_dev) != 0);
298}
299
300module_init(mon_init);
301module_exit(mon_exit);
302
303module_param_named(max_bufs, mon_max_bufs, int, 0644);
304MODULE_PARM_DESC(max_bufs, "Maximum number of sample monitor data buffers "
305 "that can be active at one time");
306
307MODULE_AUTHOR("Melissa Howland <Melissa.Howland@us.ibm.com>");
308MODULE_DESCRIPTION("Character device driver for writing z/VM "
309 "APPLDATA monitor records.");
310MODULE_LICENSE("GPL");
311
