dasd_eer.c (9caafa6c8686e319cf4d5f3757b3972c6c522b7c) dasd_eer.c (20c644680af1ef9a6b36c0873f59498c98b07ab1)
1/*
1/*
2 * character device driver for extended error reporting
2 * Character device driver for extended error reporting.
3 *
3 *
4 *
5 * Copyright (C) 2005 IBM Corporation
6 * extended error reporting for DASD ECKD devices
7 * Author(s): Stefan Weinhuber <wein@de.ibm.com>
8 *
4 * Copyright (C) 2005 IBM Corporation
5 * extended error reporting for DASD ECKD devices
6 * Author(s): Stefan Weinhuber <wein@de.ibm.com>
9 */
10
11#include <linux/init.h>
12#include <linux/fs.h>
13#include <linux/kernel.h>
14#include <linux/miscdevice.h>
15#include <linux/module.h>
16#include <linux/moduleparam.h>
17#include <linux/device.h>
7 */
8
9#include <linux/init.h>
10#include <linux/fs.h>
11#include <linux/kernel.h>
12#include <linux/miscdevice.h>
13#include <linux/module.h>
14#include <linux/moduleparam.h>
15#include <linux/device.h>
18#include <linux/workqueue.h>
19#include <linux/poll.h>
16#include <linux/poll.h>
20#include <linux/notifier.h>
21
22#include <asm/uaccess.h>
23#include <asm/semaphore.h>
24#include <asm/atomic.h>
25#include <asm/ebcdic.h>
26
27#include "dasd_int.h"
28#include "dasd_eckd.h"
29
17
18#include <asm/uaccess.h>
19#include <asm/semaphore.h>
20#include <asm/atomic.h>
21#include <asm/ebcdic.h>
22
23#include "dasd_int.h"
24#include "dasd_eckd.h"
25
30
31MODULE_LICENSE("GPL");
32
33MODULE_AUTHOR("Stefan Weinhuber <wein@de.ibm.com>");
34MODULE_DESCRIPTION("DASD extended error reporting module");
35
36
37#ifdef PRINTK_HEADER
38#undef PRINTK_HEADER
39#endif /* PRINTK_HEADER */
40#define PRINTK_HEADER "dasd(eer):"
41
26#ifdef PRINTK_HEADER
27#undef PRINTK_HEADER
28#endif /* PRINTK_HEADER */
29#define PRINTK_HEADER "dasd(eer):"
30
31/*
32 * SECTION: the internal buffer
33 */
42
34
43
44
45
46/*****************************************************************************/
47/* the internal buffer */
48/*****************************************************************************/
49
50/*
35/*
51 * The internal buffer is meant to store obaque blobs of data, so it doesn't
52 * know of higher level concepts like triggers.
36 * The internal buffer is meant to store obaque blobs of data, so it does
37 * not know of higher level concepts like triggers.
53 * It consists of a number of pages that are used as a ringbuffer. Each data
54 * blob is stored in a simple record that consists of an integer, which
55 * contains the size of the following data, and the data bytes themselfes.
56 *
57 * To allow for multiple independent readers we create one internal buffer
58 * each time the device is opened and destroy the buffer when the file is
38 * It consists of a number of pages that are used as a ringbuffer. Each data
39 * blob is stored in a simple record that consists of an integer, which
40 * contains the size of the following data, and the data bytes themselfes.
41 *
42 * To allow for multiple independent readers we create one internal buffer
43 * each time the device is opened and destroy the buffer when the file is
59 * closed again.
44 * closed again. The number of pages used for this buffer is determined by
45 * the module parmeter eer_pages.
60 *
61 * One record can be written to a buffer by using the functions
46 *
47 * One record can be written to a buffer by using the functions
62 * - dasd_eer_start_record (one time per record to write the size to the buffer
63 * and reserve the space for the data)
48 * - dasd_eer_start_record (one time per record to write the size to the
49 * buffer and reserve the space for the data)
64 * - dasd_eer_write_buffer (one or more times per record to write the data)
65 * The data can be written in several steps but you will have to compute
66 * the total size up front for the invocation of dasd_eer_start_record.
67 * If the ringbuffer is full, dasd_eer_start_record will remove the required
68 * number of old records.
69 *
70 * A record is typically read in two steps, first read the integer that
71 * specifies the size of the following data, then read the data.
72 * Both can be done by
73 * - dasd_eer_read_buffer
74 *
50 * - dasd_eer_write_buffer (one or more times per record to write the data)
51 * The data can be written in several steps but you will have to compute
52 * the total size up front for the invocation of dasd_eer_start_record.
53 * If the ringbuffer is full, dasd_eer_start_record will remove the required
54 * number of old records.
55 *
56 * A record is typically read in two steps, first read the integer that
57 * specifies the size of the following data, then read the data.
58 * Both can be done by
59 * - dasd_eer_read_buffer
60 *
75 * For all mentioned functions you need to get the bufferlock first and keep it
76 * until a complete record is written or read.
77 */
78
79
80/*
81 * Alle information necessary to keep track of an internal buffer is kept in
61 * For all mentioned functions you need to get the bufferlock first and keep
62 * it until a complete record is written or read.
63 *
64 * All information necessary to keep track of an internal buffer is kept in
82 * a struct eerbuffer. The buffer specific to a file pointer is strored in
83 * the private_data field of that file. To be able to write data to all
84 * existing buffers, each buffer is also added to the bufferlist.
65 * a struct eerbuffer. The buffer specific to a file pointer is strored in
66 * the private_data field of that file. To be able to write data to all
67 * existing buffers, each buffer is also added to the bufferlist.
85 * If the user doesn't want to read a complete record in one go, we have to
68 * If the user does not want to read a complete record in one go, we have to
86 * keep track of the rest of the record. residual stores the number of bytes
87 * that are still to deliver. If the rest of the record is invalidated between
88 * two reads then residual will be set to -1 so that the next read will fail.
89 * All entries in the eerbuffer structure are protected with the bufferlock.
90 * To avoid races between writing to a buffer on the one side and creating
91 * and destroying buffers on the other side, the bufferlock must also be used
92 * to protect the bufferlist.
93 */
94
69 * keep track of the rest of the record. residual stores the number of bytes
70 * that are still to deliver. If the rest of the record is invalidated between
71 * two reads then residual will be set to -1 so that the next read will fail.
72 * All entries in the eerbuffer structure are protected with the bufferlock.
73 * To avoid races between writing to a buffer on the one side and creating
74 * and destroying buffers on the other side, the bufferlock must also be used
75 * to protect the bufferlist.
76 */
77
78static int eer_pages = 5;
79module_param(eer_pages, int, S_IRUGO|S_IWUSR);
80
95struct eerbuffer {
96 struct list_head list;
97 char **buffer;
98 int buffersize;
99 int buffer_page_count;
100 int head;
101 int tail;
102 int residual;
103};
104
81struct eerbuffer {
82 struct list_head list;
83 char **buffer;
84 int buffersize;
85 int buffer_page_count;
86 int head;
87 int tail;
88 int residual;
89};
90
105LIST_HEAD(bufferlist);
106
91static LIST_HEAD(bufferlist);
107static spinlock_t bufferlock = SPIN_LOCK_UNLOCKED;
92static spinlock_t bufferlock = SPIN_LOCK_UNLOCKED;
93static DECLARE_WAIT_QUEUE_HEAD(dasd_eer_read_wait_queue);
108
94
109DECLARE_WAIT_QUEUE_HEAD(dasd_eer_read_wait_queue);
110
111/*
112 * How many free bytes are available on the buffer.
95/*
96 * How many free bytes are available on the buffer.
113 * needs to be called with bufferlock held
97 * Needs to be called with bufferlock held.
114 */
98 */
115static int
116dasd_eer_get_free_bytes(struct eerbuffer *eerb)
99static int dasd_eer_get_free_bytes(struct eerbuffer *eerb)
117{
100{
118 if (eerb->head < eerb->tail) {
101 if (eerb->head < eerb->tail)
119 return eerb->tail - eerb->head - 1;
102 return eerb->tail - eerb->head - 1;
120 } else
121 return eerb->buffersize - eerb->head + eerb->tail -1;
103 return eerb->buffersize - eerb->head + eerb->tail -1;
122}
123
124/*
125 * How many bytes of buffer space are used.
104}
105
106/*
107 * How many bytes of buffer space are used.
126 * needs to be called with bufferlock held
108 * Needs to be called with bufferlock held.
127 */
109 */
128static int
129dasd_eer_get_filled_bytes(struct eerbuffer *eerb)
110static int dasd_eer_get_filled_bytes(struct eerbuffer *eerb)
130{
131
111{
112
132 if (eerb->head >= eerb->tail) {
113 if (eerb->head >= eerb->tail)
133 return eerb->head - eerb->tail;
114 return eerb->head - eerb->tail;
134 } else
135 return eerb->buffersize - eerb->tail + eerb->head;
115 return eerb->buffersize - eerb->tail + eerb->head;
136}
137
138/*
139 * The dasd_eer_write_buffer function just copies count bytes of data
140 * to the buffer. Make sure to call dasd_eer_start_record first, to
141 * make sure that enough free space is available.
116}
117
118/*
119 * The dasd_eer_write_buffer function just copies count bytes of data
120 * to the buffer. Make sure to call dasd_eer_start_record first, to
121 * make sure that enough free space is available.
142 * needs to be called with bufferlock held
122 * Needs to be called with bufferlock held.
143 */
123 */
144static void
145dasd_eer_write_buffer(struct eerbuffer *eerb, int count, char *data)
124static void dasd_eer_write_buffer(struct eerbuffer *eerb,
125 char *data, int count)
146{
147
148 unsigned long headindex,localhead;
149 unsigned long rest, len;
150 char *nextdata;
151
152 nextdata = data;
153 rest = count;
154 while (rest > 0) {
155 headindex = eerb->head / PAGE_SIZE;
156 localhead = eerb->head % PAGE_SIZE;
126{
127
128 unsigned long headindex,localhead;
129 unsigned long rest, len;
130 char *nextdata;
131
132 nextdata = data;
133 rest = count;
134 while (rest > 0) {
135 headindex = eerb->head / PAGE_SIZE;
136 localhead = eerb->head % PAGE_SIZE;
157 len = min(rest, (PAGE_SIZE - localhead));
137 len = min(rest, PAGE_SIZE - localhead);
158 memcpy(eerb->buffer[headindex]+localhead, nextdata, len);
159 nextdata += len;
160 rest -= len;
161 eerb->head += len;
138 memcpy(eerb->buffer[headindex]+localhead, nextdata, len);
139 nextdata += len;
140 rest -= len;
141 eerb->head += len;
162 if ( eerb->head == eerb->buffersize )
142 if (eerb->head == eerb->buffersize)
163 eerb->head = 0; /* wrap around */
143 eerb->head = 0; /* wrap around */
164 if (eerb->head > eerb->buffersize) {
165 MESSAGE(KERN_ERR, "%s", "runaway buffer head.");
166 BUG();
167 }
144 BUG_ON(eerb->head > eerb->buffersize);
168 }
169}
170
171/*
145 }
146}
147
148/*
172 * needs to be called with bufferlock held
149 * Needs to be called with bufferlock held.
173 */
150 */
174static int
175dasd_eer_read_buffer(struct eerbuffer *eerb, int count, char *data)
151static int dasd_eer_read_buffer(struct eerbuffer *eerb, char *data, int count)
176{
177
178 unsigned long tailindex,localtail;
179 unsigned long rest, len, finalcount;
180 char *nextdata;
181
182 finalcount = min(count, dasd_eer_get_filled_bytes(eerb));
183 nextdata = data;
184 rest = finalcount;
185 while (rest > 0) {
186 tailindex = eerb->tail / PAGE_SIZE;
187 localtail = eerb->tail % PAGE_SIZE;
152{
153
154 unsigned long tailindex,localtail;
155 unsigned long rest, len, finalcount;
156 char *nextdata;
157
158 finalcount = min(count, dasd_eer_get_filled_bytes(eerb));
159 nextdata = data;
160 rest = finalcount;
161 while (rest > 0) {
162 tailindex = eerb->tail / PAGE_SIZE;
163 localtail = eerb->tail % PAGE_SIZE;
188 len = min(rest, (PAGE_SIZE - localtail));
189 memcpy(nextdata, eerb->buffer[tailindex]+localtail, len);
164 len = min(rest, PAGE_SIZE - localtail);
165 memcpy(nextdata, eerb->buffer[tailindex] + localtail, len);
190 nextdata += len;
191 rest -= len;
192 eerb->tail += len;
166 nextdata += len;
167 rest -= len;
168 eerb->tail += len;
193 if ( eerb->tail == eerb->buffersize )
169 if (eerb->tail == eerb->buffersize)
194 eerb->tail = 0; /* wrap around */
170 eerb->tail = 0; /* wrap around */
195 if (eerb->tail > eerb->buffersize) {
196 MESSAGE(KERN_ERR, "%s", "runaway buffer tail.");
197 BUG();
198 }
171 BUG_ON(eerb->tail > eerb->buffersize);
199 }
200 return finalcount;
201}
202
203/*
204 * Whenever you want to write a blob of data to the internal buffer you
205 * have to start by using this function first. It will write the number
206 * of bytes that will be written to the buffer. If necessary it will remove
207 * old records to make room for the new one.
172 }
173 return finalcount;
174}
175
176/*
177 * Whenever you want to write a blob of data to the internal buffer you
178 * have to start by using this function first. It will write the number
179 * of bytes that will be written to the buffer. If necessary it will remove
180 * old records to make room for the new one.
208 * needs to be called with bufferlock held
181 * Needs to be called with bufferlock held.
209 */
182 */
210static int
211dasd_eer_start_record(struct eerbuffer *eerb, int count)
183static int dasd_eer_start_record(struct eerbuffer *eerb, int count)
212{
213 int tailcount;
184{
185 int tailcount;
186
214 if (count + sizeof(count) > eerb->buffersize)
215 return -ENOMEM;
216 while (dasd_eer_get_free_bytes(eerb) < count + sizeof(count)) {
217 if (eerb->residual > 0) {
218 eerb->tail += eerb->residual;
219 if (eerb->tail >= eerb->buffersize)
220 eerb->tail -= eerb->buffersize;
221 eerb->residual = -1;
222 }
187 if (count + sizeof(count) > eerb->buffersize)
188 return -ENOMEM;
189 while (dasd_eer_get_free_bytes(eerb) < count + sizeof(count)) {
190 if (eerb->residual > 0) {
191 eerb->tail += eerb->residual;
192 if (eerb->tail >= eerb->buffersize)
193 eerb->tail -= eerb->buffersize;
194 eerb->residual = -1;
195 }
223 dasd_eer_read_buffer(eerb, sizeof(tailcount),
224 (char*)(&tailcount));
196 dasd_eer_read_buffer(eerb, (char *) &tailcount,
197 sizeof(tailcount));
225 eerb->tail += tailcount;
226 if (eerb->tail >= eerb->buffersize)
227 eerb->tail -= eerb->buffersize;
228 }
198 eerb->tail += tailcount;
199 if (eerb->tail >= eerb->buffersize)
200 eerb->tail -= eerb->buffersize;
201 }
229 dasd_eer_write_buffer(eerb, sizeof(count), (char*)(&count));
202 dasd_eer_write_buffer(eerb, (char*) &count, sizeof(count));
230
231 return 0;
232};
233
234/*
203
204 return 0;
205};
206
207/*
235 * release pages that are not used anymore
208 * Release pages that are not used anymore.
236 */
209 */
237static void
238dasd_eer_free_buffer_pages(char **buf, int no_pages)
210static void dasd_eer_free_buffer_pages(char **buf, int no_pages)
239{
240 int i;
241
211{
212 int i;
213
242 for (i = 0; i < no_pages; ++i) {
243 free_page((unsigned long)buf[i]);
244 }
214 for (i = 0; i < no_pages; i++)
215 free_page((unsigned long) buf[i]);
245}
246
247/*
216}
217
218/*
248 * allocate a new set of memory pages
219 * Allocate a new set of memory pages.
249 */
220 */
250static int
251dasd_eer_allocate_buffer_pages(char **buf, int no_pages)
221static int dasd_eer_allocate_buffer_pages(char **buf, int no_pages)
252{
253 int i;
254
222{
223 int i;
224
255 for (i = 0; i < no_pages; ++i) {
225 for (i = 0; i < no_pages; i++) {
256 buf[i] = (char *) get_zeroed_page(GFP_KERNEL);
257 if (!buf[i]) {
258 dasd_eer_free_buffer_pages(buf, i);
259 return -ENOMEM;
260 }
261 }
262 return 0;
263}
264
265/*
226 buf[i] = (char *) get_zeroed_page(GFP_KERNEL);
227 if (!buf[i]) {
228 dasd_eer_free_buffer_pages(buf, i);
229 return -ENOMEM;
230 }
231 }
232 return 0;
233}
234
235/*
266 * empty the buffer by resetting head and tail
267 * In case there is a half read data blob in the buffer, we set residual
268 * to -1 to indicate that the remainder of the blob is lost.
236 * SECTION: The extended error reporting functionality
269 */
237 */
270static void
271dasd_eer_purge_buffer(struct eerbuffer *eerb)
272{
273 unsigned long flags;
274
238
275 spin_lock_irqsave(&bufferlock, flags);
276 if (eerb->residual > 0)
277 eerb->residual = -1;
278 eerb->tail=0;
279 eerb->head=0;
280 spin_unlock_irqrestore(&bufferlock, flags);
281}
282
283/*
239/*
284 * set the size of the buffer, newsize is the new number of pages to be used
285 * we don't try to copy any data back an forth, so any resize will also purge
286 * the buffer
287 */
288static int
289dasd_eer_resize_buffer(struct eerbuffer *eerb, int newsize)
290{
291 int i, oldcount, reuse;
292 char **new;
293 char **old;
294 unsigned long flags;
295
296 if (newsize < 1)
297 return -EINVAL;
298 if (eerb->buffer_page_count == newsize) {
299 /* documented behaviour is that any successfull invocation
300 * will purge all records */
301 dasd_eer_purge_buffer(eerb);
302 return 0;
303 }
304 new = kmalloc(newsize*sizeof(char*), GFP_KERNEL);
305 if (!new)
306 return -ENOMEM;
307
308 reuse=min(eerb->buffer_page_count, newsize);
309 for (i = 0; i < reuse; ++i) {
310 new[i] = eerb->buffer[i];
311 }
312 if (eerb->buffer_page_count < newsize) {
313 if (dasd_eer_allocate_buffer_pages(
314 &new[eerb->buffer_page_count],
315 newsize - eerb->buffer_page_count)) {
316 kfree(new);
317 return -ENOMEM;
318 }
319 }
320
321 spin_lock_irqsave(&bufferlock, flags);
322 old = eerb->buffer;
323 eerb->buffer = new;
324 if (eerb->residual > 0)
325 eerb->residual = -1;
326 eerb->tail = 0;
327 eerb->head = 0;
328 oldcount = eerb->buffer_page_count;
329 eerb->buffer_page_count = newsize;
330 spin_unlock_irqrestore(&bufferlock, flags);
331
332 if (oldcount > newsize) {
333 for (i = newsize; i < oldcount; ++i) {
334 free_page((unsigned long)old[i]);
335 }
336 }
337 kfree(old);
338
339 return 0;
340}
341
342
343/*****************************************************************************/
344/* The extended error reporting functionality */
345/*****************************************************************************/
346
347/*
348 * When a DASD device driver wants to report an error, it calls the
240 * When a DASD device driver wants to report an error, it calls the
349 * function dasd_eer_write_trigger (via a notifier mechanism) and gives the
350 * respective trigger ID as parameter.
351 * Currently there are four kinds of triggers:
241 * function dasd_eer_write and gives the respective trigger ID as
242 * parameter. Currently there are four kinds of triggers:
352 *
353 * DASD_EER_FATALERROR: all kinds of unrecoverable I/O problems
354 * DASD_EER_PPRCSUSPEND: PPRC was suspended
355 * DASD_EER_NOPATH: There is no path to the device left.
356 * DASD_EER_STATECHANGE: The state of the device has changed.
357 *
358 * For the first three triggers all required information can be supplied by
359 * the caller. For these triggers a record is written by the function
360 * dasd_eer_write_standard_trigger.
361 *
243 *
244 * DASD_EER_FATALERROR: all kinds of unrecoverable I/O problems
245 * DASD_EER_PPRCSUSPEND: PPRC was suspended
246 * DASD_EER_NOPATH: There is no path to the device left.
247 * DASD_EER_STATECHANGE: The state of the device has changed.
248 *
249 * For the first three triggers all required information can be supplied by
250 * the caller. For these triggers a record is written by the function
251 * dasd_eer_write_standard_trigger.
252 *
362 * When dasd_eer_write_trigger is called to write a DASD_EER_STATECHANGE
363 * trigger, we have to gather the necessary sense data first. We cannot queue
364 * the necessary SNSS (sense subsystem status) request immediatly, since we
365 * are likely to run in a deadlock situation. Instead, we schedule a
366 * work_struct that calls the function dasd_eer_sense_subsystem_status to
367 * create and start an SNSS request asynchronously.
253 * The DASD_EER_STATECHANGE trigger is special since a sense subsystem
254 * status ccw need to be executed to gather the necessary sense data first.
255 * The dasd_eer_snss function will queue the SNSS request and the request
256 * callback will then call dasd_eer_write with the DASD_EER_STATCHANGE
257 * trigger.
368 *
369 * To avoid memory allocations at runtime, the necessary memory is allocated
370 * when the extended error reporting is enabled for a device (by
258 *
259 * To avoid memory allocations at runtime, the necessary memory is allocated
260 * when the extended error reporting is enabled for a device (by
371 * dasd_eer_probe). There is one private eer data structure for each eer
372 * enabled DASD device. It contains memory for the work_struct, one SNSS cqr
373 * and a flags field that is used to coordinate the use of the cqr. The call
374 * to write a state change trigger can come in at any time, so we have one flag
375 * CQR_IN_USE that protects the cqr itself. When this flag indicates that the
376 * cqr is currently in use, dasd_eer_sense_subsystem_status cannot start a
377 * second request but sets the SNSS_REQUESTED flag instead.
378 *
379 * When the request is finished, the callback function dasd_eer_SNSS_cb
380 * is called. This function will invoke the function
381 * dasd_eer_write_SNSS_trigger to finally write the trigger. It will also
382 * check the SNSS_REQUESTED flag and if it is set it will call
383 * dasd_eer_sense_subsystem_status again.
384 *
385 * To avoid race conditions during the handling of the lock, the flags must
386 * be protected by the snsslock.
261 * dasd_eer_probe). There is one sense subsystem status request for each
262 * eer enabled DASD device. The presence of the cqr in device->eer_cqr
263 * indicates that eer is enable for the device. The use of the snss request
264 * is protected by the DASD_FLAG_EER_IN_USE bit. When this flag indicates
265 * that the cqr is currently in use, dasd_eer_snss cannot start a second
266 * request but sets the DASD_FLAG_EER_SNSS flag instead. The callback of
267 * the SNSS request will check the bit and call dasd_eer_snss again.
387 */
388
268 */
269
389struct dasd_eer_private {
390 struct dasd_ccw_req *cqr;
391 unsigned long flags;
392 struct work_struct worker;
393};
394
395static void dasd_eer_destroy(struct dasd_device *device,
396 struct dasd_eer_private *eer);
397static int
398dasd_eer_write_trigger(struct dasd_eer_trigger *trigger);
399static void dasd_eer_sense_subsystem_status(void *data);
400static int dasd_eer_notify(struct notifier_block *self,
401 unsigned long action, void *data);
402
403struct workqueue_struct *dasd_eer_workqueue;
404
405#define SNSS_DATA_SIZE 44
270#define SNSS_DATA_SIZE 44
406static spinlock_t snsslock = SPIN_LOCK_UNLOCKED;
407
408#define DASD_EER_BUSID_SIZE 10
409struct dasd_eer_header {
410 __u32 total_size;
411 __u32 trigger;
412 __u64 tv_sec;
413 __u64 tv_usec;
414 char busid[DASD_EER_BUSID_SIZE];
271
272#define DASD_EER_BUSID_SIZE 10
273struct dasd_eer_header {
274 __u32 total_size;
275 __u32 trigger;
276 __u64 tv_sec;
277 __u64 tv_usec;
278 char busid[DASD_EER_BUSID_SIZE];
415} __attribute__ ((packed));
416
417static struct notifier_block dasd_eer_nb = {
418 .notifier_call = dasd_eer_notify,
419};
420
421/*
279};
280
281/*
422 * flags for use with dasd_eer_private
423 */
424#define CQR_IN_USE 0
425#define SNSS_REQUESTED 1
426
427/*
428 * This function checks if extended error reporting is available for a given
429 * dasd_device. If yes, then it creates and returns a struct dasd_eer,
430 * otherwise it returns an -EPERM error pointer.
431 */
432struct dasd_eer_private *
433dasd_eer_probe(struct dasd_device *device)
434{
435 struct dasd_eer_private *private;
436
437 if (!(device && device->discipline
438 && !strcmp(device->discipline->name, "ECKD"))) {
439 return ERR_PTR(-EPERM);
440 }
441 /* allocate the private data structure */
442 private = (struct dasd_eer_private *)kmalloc(
443 sizeof(struct dasd_eer_private), GFP_KERNEL);
444 if (!private) {
445 return ERR_PTR(-ENOMEM);
446 }
447 INIT_WORK(&private->worker, dasd_eer_sense_subsystem_status,
448 (void *)device);
449 private->cqr = dasd_kmalloc_request("ECKD",
450 1 /* SNSS */ ,
451 SNSS_DATA_SIZE ,
452 device);
453 if (!private->cqr) {
454 kfree(private);
455 return ERR_PTR(-ENOMEM);
456 }
457 private->flags = 0;
458 return private;
459};
460
461/*
462 * If our private SNSS request is queued, remove it from the
463 * dasd ccw queue so we can free the requests memory.
464 */
465static void
466dasd_eer_dequeue_SNSS_request(struct dasd_device *device,
467 struct dasd_eer_private *eer)
468{
469 struct list_head *lst, *nxt;
470 struct dasd_ccw_req *cqr, *erpcqr;
471 dasd_erp_fn_t erp_fn;
472
473 spin_lock_irq(get_ccwdev_lock(device->cdev));
474 list_for_each_safe(lst, nxt, &device->ccw_queue) {
475 cqr = list_entry(lst, struct dasd_ccw_req, list);
476 /* we are looking for two kinds or requests */
477 /* first kind: our SNSS request: */
478 if (cqr == eer->cqr) {
479 if (cqr->status == DASD_CQR_IN_IO)
480 device->discipline->term_IO(cqr);
481 list_del(&cqr->list);
482 break;
483 }
484 /* second kind: ERP requests for our SNSS request */
485 if (cqr->refers) {
486 /* If this erp request chain ends in our cqr, then */
487 /* cal the erp_postaction to clean it up */
488 erpcqr = cqr;
489 while (erpcqr->refers) {
490 erpcqr = erpcqr->refers;
491 }
492 if (erpcqr == eer->cqr) {
493 erp_fn = device->discipline->erp_postaction(
494 cqr);
495 erp_fn(cqr);
496 }
497 continue;
498 }
499 }
500 spin_unlock_irq(get_ccwdev_lock(device->cdev));
501}
502
503/*
504 * This function dismantles a struct dasd_eer that was created by
505 * dasd_eer_probe. Since we want to free our private data structure,
506 * we must make sure that the memory is not in use anymore.
507 * We have to flush the work queue and remove a possible SNSS request
508 * from the dasd queue.
509 */
510static void
511dasd_eer_destroy(struct dasd_device *device, struct dasd_eer_private *eer)
512{
513 flush_workqueue(dasd_eer_workqueue);
514 dasd_eer_dequeue_SNSS_request(device, eer);
515 dasd_kfree_request(eer->cqr, device);
516 kfree(eer);
517};
518
519/*
520 * enable the extended error reporting for a particular device
521 */
522static int
523dasd_eer_enable_on_device(struct dasd_device *device)
524{
525 void *eer;
526 if (!device)
527 return -ENODEV;
528 if (device->eer)
529 return 0;
530 if (!try_module_get(THIS_MODULE)) {
531 return -EINVAL;
532 }
533 eer = (void *)dasd_eer_probe(device);
534 if (IS_ERR(eer)) {
535 module_put(THIS_MODULE);
536 return PTR_ERR(eer);
537 }
538 device->eer = eer;
539 return 0;
540}
541
542/*
543 * enable the extended error reporting for a particular device
544 */
545static int
546dasd_eer_disable_on_device(struct dasd_device *device)
547{
548 struct dasd_eer_private *eer = device->eer;
549
550 if (!device)
551 return -ENODEV;
552 if (!device->eer)
553 return 0;
554 device->eer = NULL;
555 dasd_eer_destroy(device,eer);
556 module_put(THIS_MODULE);
557
558 return 0;
559}
560
561/*
562 * Set extended error reporting (eer)
563 * Note: This will be registered as a DASD ioctl, to be called on DASD devices.
564 */
565static int
566dasd_ioctl_set_eer(struct block_device *bdev, int no, long args)
567{
568 struct dasd_device *device;
569 int intval;
570
571 if (!capable(CAP_SYS_ADMIN))
572 return -EACCES;
573 if (bdev != bdev->bd_contains)
574 /* Error-reporting is not allowed for partitions */
575 return -EINVAL;
576 if (get_user(intval, (int __user *) args))
577 return -EFAULT;
578 device = bdev->bd_disk->private_data;
579 if (device == NULL)
580 return -ENODEV;
581
582 intval = (intval != 0);
583 DEV_MESSAGE (KERN_DEBUG, device,
584 "set eer on device to %d", intval);
585 if (intval)
586 return dasd_eer_enable_on_device(device);
587 else
588 return dasd_eer_disable_on_device(device);
589}
590
591/*
592 * Get value of extended error reporting.
593 * Note: This will be registered as a DASD ioctl, to be called on DASD devices.
594 */
595static int
596dasd_ioctl_get_eer(struct block_device *bdev, int no, long args)
597{
598 struct dasd_device *device;
599
600 device = bdev->bd_disk->private_data;
601 if (device == NULL)
602 return -ENODEV;
603 return put_user((device->eer != NULL), (int __user *) args);
604}
605
606/*
607 * The following function can be used for those triggers that have
608 * all necessary data available when the function is called.
609 * If the parameter cqr is not NULL, the chain of requests will be searched
610 * for valid sense data, and all valid sense data sets will be added to
611 * the triggers data.
612 */
282 * The following function can be used for those triggers that have
283 * all necessary data available when the function is called.
284 * If the parameter cqr is not NULL, the chain of requests will be searched
285 * for valid sense data, and all valid sense data sets will be added to
286 * the triggers data.
287 */
613static int
614dasd_eer_write_standard_trigger(int trigger, struct dasd_device *device,
615 struct dasd_ccw_req *cqr)
288static void dasd_eer_write_standard_trigger(struct dasd_device *device,
289 struct dasd_ccw_req *cqr,
290 int trigger)
616{
617 struct dasd_ccw_req *temp_cqr;
618 int data_size;
619 struct timeval tv;
620 struct dasd_eer_header header;
621 unsigned long flags;
622 struct eerbuffer *eerb;
623
624 /* go through cqr chain and count the valid sense data sets */
291{
292 struct dasd_ccw_req *temp_cqr;
293 int data_size;
294 struct timeval tv;
295 struct dasd_eer_header header;
296 unsigned long flags;
297 struct eerbuffer *eerb;
298
299 /* go through cqr chain and count the valid sense data sets */
625 temp_cqr = cqr;
626 data_size = 0;
300 data_size = 0;
627 while (temp_cqr) {
301 for (temp_cqr = cqr; temp_cqr; temp_cqr = temp_cqr->refers)
628 if (temp_cqr->irb.esw.esw0.erw.cons)
629 data_size += 32;
302 if (temp_cqr->irb.esw.esw0.erw.cons)
303 data_size += 32;
630 temp_cqr = temp_cqr->refers;
631 }
632
633 header.total_size = sizeof(header) + data_size + 4; /* "EOR" */
634 header.trigger = trigger;
635 do_gettimeofday(&tv);
636 header.tv_sec = tv.tv_sec;
637 header.tv_usec = tv.tv_usec;
638 strncpy(header.busid, device->cdev->dev.bus_id, DASD_EER_BUSID_SIZE);
639
640 spin_lock_irqsave(&bufferlock, flags);
641 list_for_each_entry(eerb, &bufferlist, list) {
642 dasd_eer_start_record(eerb, header.total_size);
304
305 header.total_size = sizeof(header) + data_size + 4; /* "EOR" */
306 header.trigger = trigger;
307 do_gettimeofday(&tv);
308 header.tv_sec = tv.tv_sec;
309 header.tv_usec = tv.tv_usec;
310 strncpy(header.busid, device->cdev->dev.bus_id, DASD_EER_BUSID_SIZE);
311
312 spin_lock_irqsave(&bufferlock, flags);
313 list_for_each_entry(eerb, &bufferlist, list) {
314 dasd_eer_start_record(eerb, header.total_size);
643 dasd_eer_write_buffer(eerb, sizeof(header), (char*)(&header));
644 temp_cqr = cqr;
645 while (temp_cqr) {
315 dasd_eer_write_buffer(eerb, (char *) &header, sizeof(header));
316 for (temp_cqr = cqr; temp_cqr; temp_cqr = temp_cqr->refers)
646 if (temp_cqr->irb.esw.esw0.erw.cons)
317 if (temp_cqr->irb.esw.esw0.erw.cons)
647 dasd_eer_write_buffer(eerb, 32, cqr->irb.ecw);
648 temp_cqr = temp_cqr->refers;
649 }
650 dasd_eer_write_buffer(eerb, 4,"EOR");
318 dasd_eer_write_buffer(eerb, cqr->irb.ecw, 32);
319 dasd_eer_write_buffer(eerb, "EOR", 4);
651 }
652 spin_unlock_irqrestore(&bufferlock, flags);
320 }
321 spin_unlock_irqrestore(&bufferlock, flags);
653
654 wake_up_interruptible(&dasd_eer_read_wait_queue);
322 wake_up_interruptible(&dasd_eer_read_wait_queue);
655
656 return 0;
657}
658
659/*
660 * This function writes a DASD_EER_STATECHANGE trigger.
661 */
323}
324
325/*
326 * This function writes a DASD_EER_STATECHANGE trigger.
327 */
662static void
663dasd_eer_write_SNSS_trigger(struct dasd_device *device,
664 struct dasd_ccw_req *cqr)
328static void dasd_eer_write_snss_trigger(struct dasd_device *device,
329 struct dasd_ccw_req *cqr,
330 int trigger)
665{
666 int data_size;
667 int snss_rc;
668 struct timeval tv;
669 struct dasd_eer_header header;
670 unsigned long flags;
671 struct eerbuffer *eerb;
672

--- 8 unchanged lines hidden (view full) ---

681 do_gettimeofday(&tv);
682 header.tv_sec = tv.tv_sec;
683 header.tv_usec = tv.tv_usec;
684 strncpy(header.busid, device->cdev->dev.bus_id, DASD_EER_BUSID_SIZE);
685
686 spin_lock_irqsave(&bufferlock, flags);
687 list_for_each_entry(eerb, &bufferlist, list) {
688 dasd_eer_start_record(eerb, header.total_size);
331{
332 int data_size;
333 int snss_rc;
334 struct timeval tv;
335 struct dasd_eer_header header;
336 unsigned long flags;
337 struct eerbuffer *eerb;
338

--- 8 unchanged lines hidden (view full) ---

347 do_gettimeofday(&tv);
348 header.tv_sec = tv.tv_sec;
349 header.tv_usec = tv.tv_usec;
350 strncpy(header.busid, device->cdev->dev.bus_id, DASD_EER_BUSID_SIZE);
351
352 spin_lock_irqsave(&bufferlock, flags);
353 list_for_each_entry(eerb, &bufferlist, list) {
354 dasd_eer_start_record(eerb, header.total_size);
689 dasd_eer_write_buffer(eerb, sizeof(header),(char*)(&header));
355 dasd_eer_write_buffer(eerb, (char *) &header , sizeof(header));
690 if (!snss_rc)
356 if (!snss_rc)
691 dasd_eer_write_buffer(eerb, SNSS_DATA_SIZE, cqr->data);
692 dasd_eer_write_buffer(eerb, 4,"EOR");
357 dasd_eer_write_buffer(eerb, cqr->data, SNSS_DATA_SIZE);
358 dasd_eer_write_buffer(eerb, "EOR", 4);
693 }
694 spin_unlock_irqrestore(&bufferlock, flags);
359 }
360 spin_unlock_irqrestore(&bufferlock, flags);
695
696 wake_up_interruptible(&dasd_eer_read_wait_queue);
697}
698
699/*
361 wake_up_interruptible(&dasd_eer_read_wait_queue);
362}
363
364/*
700 * callback function for use with SNSS request
365 * This function is called for all triggers. It calls the appropriate
366 * function that writes the actual trigger records.
701 */
367 */
702static void
703dasd_eer_SNSS_cb(struct dasd_ccw_req *cqr, void *data)
368void dasd_eer_write(struct dasd_device *device, struct dasd_ccw_req *cqr,
369 unsigned int id)
704{
370{
705 struct dasd_device *device;
706 struct dasd_eer_private *private;
707 unsigned long irqflags;
371 if (!device->eer_cqr)
372 return;
373 switch (id) {
374 case DASD_EER_FATALERROR:
375 case DASD_EER_PPRCSUSPEND:
376 dasd_eer_write_standard_trigger(device, cqr, id);
377 break;
378 case DASD_EER_NOPATH:
379 dasd_eer_write_standard_trigger(device, NULL, id);
380 break;
381 case DASD_EER_STATECHANGE:
382 dasd_eer_write_snss_trigger(device, cqr, id);
383 break;
384 default: /* unknown trigger, so we write it without any sense data */
385 dasd_eer_write_standard_trigger(device, NULL, id);
386 break;
387 }
388}
389EXPORT_SYMBOL(dasd_eer_write);
708
390
709 device = (struct dasd_device *)data;
710 private = (struct dasd_eer_private *)device->eer;
711 dasd_eer_write_SNSS_trigger(device, cqr);
712 spin_lock_irqsave(&snsslock, irqflags);
713 if(!test_and_clear_bit(SNSS_REQUESTED, &private->flags)) {
714 clear_bit(CQR_IN_USE, &private->flags);
715 spin_unlock_irqrestore(&snsslock, irqflags);
391/*
392 * Start a sense subsystem status request.
393 * Needs to be called with the device held.
394 */
395void dasd_eer_snss(struct dasd_device *device)
396{
397 struct dasd_ccw_req *cqr;
398
399 cqr = device->eer_cqr;
400 if (!cqr) /* Device not eer enabled. */
716 return;
401 return;
717 };
718 clear_bit(CQR_IN_USE, &private->flags);
719 spin_unlock_irqrestore(&snsslock, irqflags);
720 dasd_eer_sense_subsystem_status(device);
721 return;
402 if (test_and_set_bit(DASD_FLAG_EER_IN_USE, &device->flags)) {
403 /* Sense subsystem status request in use. */
404 set_bit(DASD_FLAG_EER_SNSS, &device->flags);
405 return;
406 }
407 clear_bit(DASD_FLAG_EER_SNSS, &device->flags);
408 cqr->status = DASD_CQR_QUEUED;
409 list_add(&cqr->list, &device->ccw_queue);
410 dasd_schedule_bh(device);
722}
723
724/*
411}
412
413/*
725 * clean a used cqr before using it again
414 * Callback function for use with sense subsystem status request.
726 */
415 */
727static void
728dasd_eer_clean_SNSS_request(struct dasd_ccw_req *cqr)
416static void dasd_eer_snss_cb(struct dasd_ccw_req *cqr, void *data)
729{
417{
730 struct ccw1 *cpaddr = cqr->cpaddr;
731 void *data = cqr->data;
418 struct dasd_device *device = cqr->device;
419 unsigned long flags;
732
420
733 memset(cqr, 0, sizeof(struct dasd_ccw_req));
734 memset(cpaddr, 0, sizeof(struct ccw1));
735 memset(data, 0, SNSS_DATA_SIZE);
736 cqr->cpaddr = cpaddr;
737 cqr->data = data;
738 strncpy((char *) &cqr->magic, "ECKD", 4);
739 ASCEBC((char *) &cqr->magic, 4);
740 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
421 dasd_eer_write(device, cqr, DASD_EER_STATECHANGE);
422 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
423 if (device->eer_cqr == cqr) {
424 clear_bit(DASD_FLAG_EER_IN_USE, &device->flags);
425 if (test_bit(DASD_FLAG_EER_SNSS, &device->flags))
426 /* Another SNSS has been requested in the meantime. */
427 dasd_eer_snss(device);
428 cqr = NULL;
429 }
430 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
431 if (cqr)
432 /*
433 * Extended error recovery has been switched off while
434 * the SNSS request was running. It could even have
435 * been switched off and on again in which case there
436 * is a new ccw in device->eer_cqr. Free the "old"
437 * snss request now.
438 */
439 dasd_kfree_request(cqr, device);
741}
742
743/*
440}
441
442/*
744 * build and start an SNSS request
745 * This function is called from a work queue so we have to
746 * pass the dasd_device pointer as a void pointer.
443 * Enable error reporting on a given device.
747 */
444 */
748static void
749dasd_eer_sense_subsystem_status(void *data)
445int dasd_eer_enable(struct dasd_device *device)
750{
446{
751 struct dasd_device *device;
752 struct dasd_eer_private *private;
753 struct dasd_ccw_req *cqr;
447 struct dasd_ccw_req *cqr;
754 struct ccw1 *ccw;
755 unsigned long irqflags;
448 unsigned long flags;
756
449
757 device = (struct dasd_device *)data;
758 private = (struct dasd_eer_private *)device->eer;
759 if (!private) /* device not eer enabled any more */
760 return;
761 cqr = private->cqr;
762 spin_lock_irqsave(&snsslock, irqflags);
763 if(test_and_set_bit(CQR_IN_USE, &private->flags)) {
764 set_bit(SNSS_REQUESTED, &private->flags);
765 spin_unlock_irqrestore(&snsslock, irqflags);
766 return;
767 };
768 spin_unlock_irqrestore(&snsslock, irqflags);
769 dasd_eer_clean_SNSS_request(cqr);
450 if (device->eer_cqr)
451 return 0;
452
453 if (!device->discipline || strcmp(device->discipline->name, "ECKD"))
454 return -EPERM; /* FIXME: -EMEDIUMTYPE ? */
455
456 cqr = dasd_kmalloc_request("ECKD", 1 /* SNSS */,
457 SNSS_DATA_SIZE, device);
458 if (!cqr)
459 return -ENOMEM;
460
770 cqr->device = device;
771 cqr->retries = 255;
772 cqr->expires = 10 * HZ;
773
461 cqr->device = device;
462 cqr->retries = 255;
463 cqr->expires = 10 * HZ;
464
774 ccw = cqr->cpaddr;
775 ccw->cmd_code = DASD_ECKD_CCW_SNSS;
776 ccw->count = SNSS_DATA_SIZE;
777 ccw->flags = 0;
778 ccw->cda = (__u32)(addr_t)cqr->data;
465 cqr->cpaddr->cmd_code = DASD_ECKD_CCW_SNSS;
466 cqr->cpaddr->count = SNSS_DATA_SIZE;
467 cqr->cpaddr->flags = 0;
468 cqr->cpaddr->cda = (__u32)(addr_t) cqr->data;
779
780 cqr->buildclk = get_clock();
781 cqr->status = DASD_CQR_FILLED;
469
470 cqr->buildclk = get_clock();
471 cqr->status = DASD_CQR_FILLED;
782 cqr->callback = dasd_eer_SNSS_cb;
783 cqr->callback_data = (void *)device;
784 dasd_add_request_head(cqr);
472 cqr->callback = dasd_eer_snss_cb;
785
473
786 return;
474 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
475 if (!device->eer_cqr) {
476 device->eer_cqr = cqr;
477 cqr = NULL;
478 }
479 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
480 if (cqr)
481 dasd_kfree_request(cqr, device);
482 return 0;
787}
788
789/*
483}
484
485/*
790 * This function is called for all triggers. It calls the appropriate
791 * function that writes the actual trigger records.
486 * Disable error reporting on a given device.
792 */
487 */
793static int
794dasd_eer_write_trigger(struct dasd_eer_trigger *trigger)
488void dasd_eer_disable(struct dasd_device *device)
795{
489{
796 int rc;
797 struct dasd_eer_private *private = trigger->device->eer;
490 struct dasd_ccw_req *cqr;
491 unsigned long flags;
492 int in_use;
798
493
799 switch (trigger->id) {
800 case DASD_EER_FATALERROR:
801 case DASD_EER_PPRCSUSPEND:
802 rc = dasd_eer_write_standard_trigger(
803 trigger->id, trigger->device, trigger->cqr);
804 break;
805 case DASD_EER_NOPATH:
806 rc = dasd_eer_write_standard_trigger(
807 trigger->id, trigger->device, NULL);
808 break;
809 case DASD_EER_STATECHANGE:
810 if (queue_work(dasd_eer_workqueue, &private->worker)) {
811 rc=0;
812 } else {
813 /* If the work_struct was already queued, it can't
814 * be queued again. But this is OK since we don't
815 * need to have it queued twice.
816 */
817 rc = -EBUSY;
818 }
819 break;
820 default: /* unknown trigger, so we write it without any sense data */
821 rc = dasd_eer_write_standard_trigger(
822 trigger->id, trigger->device, NULL);
823 break;
824 }
825 return rc;
494 if (!device->eer_cqr)
495 return;
496 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
497 cqr = device->eer_cqr;
498 device->eer_cqr = NULL;
499 clear_bit(DASD_FLAG_EER_SNSS, &device->flags);
500 in_use = test_and_clear_bit(DASD_FLAG_EER_IN_USE, &device->flags);
501 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
502 if (cqr && !in_use)
503 dasd_kfree_request(cqr, device);
826}
827
828/*
504}
505
506/*
829 * This function is registered with the dasd device driver and gets called
830 * for all dasd eer notifications.
507 * SECTION: the device operations
831 */
508 */
832static int dasd_eer_notify(struct notifier_block *self,
833 unsigned long action, void *data)
834{
835 switch (action) {
836 case DASD_EER_DISABLE:
837 dasd_eer_disable_on_device((struct dasd_device *)data);
838 break;
839 case DASD_EER_TRIGGER:
840 dasd_eer_write_trigger((struct dasd_eer_trigger *)data);
841 break;
842 }
843 return NOTIFY_OK;
844}
845
509
846
847/*****************************************************************************/
848/* the device operations */
849/*****************************************************************************/
850
851/*
852 * On the one side we need a lock to access our internal buffer, on the
853 * other side a copy_to_user can sleep. So we need to copy the data we have
854 * to transfer in a readbuffer, which is protected by the readbuffer_mutex.
855 */
856static char readbuffer[PAGE_SIZE];
510/*
511 * On the one side we need a lock to access our internal buffer, on the
512 * other side a copy_to_user can sleep. So we need to copy the data we have
513 * to transfer in a readbuffer, which is protected by the readbuffer_mutex.
514 */
515static char readbuffer[PAGE_SIZE];
857DECLARE_MUTEX(readbuffer_mutex);
516static DECLARE_MUTEX(readbuffer_mutex);
858
517
859
860static int
861dasd_eer_open(struct inode *inp, struct file *filp)
518static int dasd_eer_open(struct inode *inp, struct file *filp)
862{
863 struct eerbuffer *eerb;
864 unsigned long flags;
865
519{
520 struct eerbuffer *eerb;
521 unsigned long flags;
522
866 eerb = kmalloc(sizeof(struct eerbuffer), GFP_KERNEL);
867 eerb->head = 0;
868 eerb->tail = 0;
869 eerb->residual = 0;
870 eerb->buffer_page_count = 1;
523 eerb = kzalloc(sizeof(struct eerbuffer), GFP_KERNEL);
524 eerb->buffer_page_count = eer_pages;
525 if (eerb->buffer_page_count < 1 ||
526 eerb->buffer_page_count > INT_MAX / PAGE_SIZE) {
527 kfree(eerb);
528 MESSAGE(KERN_WARNING, "can't open device since module "
529 "parameter eer_pages is smaller then 1 or"
530 " bigger then %d", (int)(INT_MAX / PAGE_SIZE));
531 return -EINVAL;
532 }
871 eerb->buffersize = eerb->buffer_page_count * PAGE_SIZE;
533 eerb->buffersize = eerb->buffer_page_count * PAGE_SIZE;
872 eerb->buffer = kmalloc(eerb->buffer_page_count*sizeof(char*),
534 eerb->buffer = kmalloc(eerb->buffer_page_count * sizeof(char *),
873 GFP_KERNEL);
535 GFP_KERNEL);
874 if (!eerb->buffer)
536 if (!eerb->buffer) {
537 kfree(eerb);
875 return -ENOMEM;
538 return -ENOMEM;
539 }
876 if (dasd_eer_allocate_buffer_pages(eerb->buffer,
877 eerb->buffer_page_count)) {
878 kfree(eerb->buffer);
540 if (dasd_eer_allocate_buffer_pages(eerb->buffer,
541 eerb->buffer_page_count)) {
542 kfree(eerb->buffer);
543 kfree(eerb);
879 return -ENOMEM;
880 }
881 filp->private_data = eerb;
882 spin_lock_irqsave(&bufferlock, flags);
883 list_add(&eerb->list, &bufferlist);
884 spin_unlock_irqrestore(&bufferlock, flags);
885
886 return nonseekable_open(inp,filp);
887}
888
544 return -ENOMEM;
545 }
546 filp->private_data = eerb;
547 spin_lock_irqsave(&bufferlock, flags);
548 list_add(&eerb->list, &bufferlist);
549 spin_unlock_irqrestore(&bufferlock, flags);
550
551 return nonseekable_open(inp,filp);
552}
553
889static int
890dasd_eer_close(struct inode *inp, struct file *filp)
554static int dasd_eer_close(struct inode *inp, struct file *filp)
891{
892 struct eerbuffer *eerb;
893 unsigned long flags;
894
555{
556 struct eerbuffer *eerb;
557 unsigned long flags;
558
895 eerb = (struct eerbuffer *)filp->private_data;
559 eerb = (struct eerbuffer *) filp->private_data;
896 spin_lock_irqsave(&bufferlock, flags);
897 list_del(&eerb->list);
898 spin_unlock_irqrestore(&bufferlock, flags);
899 dasd_eer_free_buffer_pages(eerb->buffer, eerb->buffer_page_count);
900 kfree(eerb->buffer);
901 kfree(eerb);
902
903 return 0;
904}
905
560 spin_lock_irqsave(&bufferlock, flags);
561 list_del(&eerb->list);
562 spin_unlock_irqrestore(&bufferlock, flags);
563 dasd_eer_free_buffer_pages(eerb->buffer, eerb->buffer_page_count);
564 kfree(eerb->buffer);
565 kfree(eerb);
566
567 return 0;
568}
569
906static long
907dasd_eer_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
570static ssize_t dasd_eer_read(struct file *filp, char __user *buf,
571 size_t count, loff_t *ppos)
908{
572{
909 int intval;
910 struct eerbuffer *eerb;
911
912 eerb = (struct eerbuffer *)filp->private_data;
913 switch (cmd) {
914 case DASD_EER_PURGE:
915 dasd_eer_purge_buffer(eerb);
916 return 0;
917 case DASD_EER_SETBUFSIZE:
918 if (get_user(intval, (int __user *)arg))
919 return -EFAULT;
920 return dasd_eer_resize_buffer(eerb, intval);
921 default:
922 return -ENOIOCTLCMD;
923 }
924}
925
926static ssize_t
927dasd_eer_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos)
928{
929 int tc,rc;
930 int tailcount,effective_count;
931 unsigned long flags;
932 struct eerbuffer *eerb;
933
573 int tc,rc;
574 int tailcount,effective_count;
575 unsigned long flags;
576 struct eerbuffer *eerb;
577
934 eerb = (struct eerbuffer *)filp->private_data;
935 if(down_interruptible(&readbuffer_mutex))
578 eerb = (struct eerbuffer *) filp->private_data;
579 if (down_interruptible(&readbuffer_mutex))
936 return -ERESTARTSYS;
937
938 spin_lock_irqsave(&bufferlock, flags);
939
940 if (eerb->residual < 0) { /* the remainder of this record */
941 /* has been deleted */
942 eerb->residual = 0;
943 spin_unlock_irqrestore(&bufferlock, flags);
944 up(&readbuffer_mutex);
945 return -EIO;
946 } else if (eerb->residual > 0) {
947 /* OK we still have a second half of a record to deliver */
580 return -ERESTARTSYS;
581
582 spin_lock_irqsave(&bufferlock, flags);
583
584 if (eerb->residual < 0) { /* the remainder of this record */
585 /* has been deleted */
586 eerb->residual = 0;
587 spin_unlock_irqrestore(&bufferlock, flags);
588 up(&readbuffer_mutex);
589 return -EIO;
590 } else if (eerb->residual > 0) {
591 /* OK we still have a second half of a record to deliver */
948 effective_count = min(eerb->residual, (int)count);
592 effective_count = min(eerb->residual, (int) count);
949 eerb->residual -= effective_count;
950 } else {
951 tc = 0;
952 while (!tc) {
593 eerb->residual -= effective_count;
594 } else {
595 tc = 0;
596 while (!tc) {
953 tc = dasd_eer_read_buffer(eerb,
954 sizeof(tailcount), (char*)(&tailcount));
597 tc = dasd_eer_read_buffer(eerb, (char *) &tailcount,
598 sizeof(tailcount));
955 if (!tc) {
956 /* no data available */
957 spin_unlock_irqrestore(&bufferlock, flags);
958 up(&readbuffer_mutex);
959 if (filp->f_flags & O_NONBLOCK)
960 return -EAGAIN;
961 rc = wait_event_interruptible(
962 dasd_eer_read_wait_queue,
963 eerb->head != eerb->tail);
599 if (!tc) {
600 /* no data available */
601 spin_unlock_irqrestore(&bufferlock, flags);
602 up(&readbuffer_mutex);
603 if (filp->f_flags & O_NONBLOCK)
604 return -EAGAIN;
605 rc = wait_event_interruptible(
606 dasd_eer_read_wait_queue,
607 eerb->head != eerb->tail);
964 if (rc) {
608 if (rc)
965 return rc;
609 return rc;
966 }
967 if(down_interruptible(&readbuffer_mutex))
610 if (down_interruptible(&readbuffer_mutex))
968 return -ERESTARTSYS;
969 spin_lock_irqsave(&bufferlock, flags);
970 }
971 }
972 WARN_ON(tc != sizeof(tailcount));
973 effective_count = min(tailcount,(int)count);
974 eerb->residual = tailcount - effective_count;
975 }
976
611 return -ERESTARTSYS;
612 spin_lock_irqsave(&bufferlock, flags);
613 }
614 }
615 WARN_ON(tc != sizeof(tailcount));
616 effective_count = min(tailcount,(int)count);
617 eerb->residual = tailcount - effective_count;
618 }
619
977 tc = dasd_eer_read_buffer(eerb, effective_count, readbuffer);
620 tc = dasd_eer_read_buffer(eerb, readbuffer, effective_count);
978 WARN_ON(tc != effective_count);
979
980 spin_unlock_irqrestore(&bufferlock, flags);
981
982 if (copy_to_user(buf, readbuffer, effective_count)) {
983 up(&readbuffer_mutex);
984 return -EFAULT;
985 }
986
987 up(&readbuffer_mutex);
988 return effective_count;
989}
990
621 WARN_ON(tc != effective_count);
622
623 spin_unlock_irqrestore(&bufferlock, flags);
624
625 if (copy_to_user(buf, readbuffer, effective_count)) {
626 up(&readbuffer_mutex);
627 return -EFAULT;
628 }
629
630 up(&readbuffer_mutex);
631 return effective_count;
632}
633
991static unsigned int
992dasd_eer_poll (struct file *filp, poll_table *ptable)
634static unsigned int dasd_eer_poll(struct file *filp, poll_table *ptable)
993{
994 unsigned int mask;
995 unsigned long flags;
996 struct eerbuffer *eerb;
997
635{
636 unsigned int mask;
637 unsigned long flags;
638 struct eerbuffer *eerb;
639
998 eerb = (struct eerbuffer *)filp->private_data;
640 eerb = (struct eerbuffer *) filp->private_data;
999 poll_wait(filp, &dasd_eer_read_wait_queue, ptable);
1000 spin_lock_irqsave(&bufferlock, flags);
1001 if (eerb->head != eerb->tail)
1002 mask = POLLIN | POLLRDNORM ;
1003 else
1004 mask = 0;
1005 spin_unlock_irqrestore(&bufferlock, flags);
1006 return mask;
1007}
1008
1009static struct file_operations dasd_eer_fops = {
1010 .open = &dasd_eer_open,
1011 .release = &dasd_eer_close,
641 poll_wait(filp, &dasd_eer_read_wait_queue, ptable);
642 spin_lock_irqsave(&bufferlock, flags);
643 if (eerb->head != eerb->tail)
644 mask = POLLIN | POLLRDNORM ;
645 else
646 mask = 0;
647 spin_unlock_irqrestore(&bufferlock, flags);
648 return mask;
649}
650
651static struct file_operations dasd_eer_fops = {
652 .open = &dasd_eer_open,
653 .release = &dasd_eer_close,
1012 .unlocked_ioctl = &dasd_eer_ioctl,
1013 .compat_ioctl = &dasd_eer_ioctl,
1014 .read = &dasd_eer_read,
1015 .poll = &dasd_eer_poll,
1016 .owner = THIS_MODULE,
1017};
1018
1019static struct miscdevice dasd_eer_dev = {
1020 .minor = MISC_DYNAMIC_MINOR,
1021 .name = "dasd_eer",
1022 .fops = &dasd_eer_fops,
1023};
1024
654 .read = &dasd_eer_read,
655 .poll = &dasd_eer_poll,
656 .owner = THIS_MODULE,
657};
658
659static struct miscdevice dasd_eer_dev = {
660 .minor = MISC_DYNAMIC_MINOR,
661 .name = "dasd_eer",
662 .fops = &dasd_eer_fops,
663};
664
1025
1026/*****************************************************************************/
1027/* Init and exit */
1028/*****************************************************************************/
1029
1030static int
1031__init dasd_eer_init(void)
665int __init dasd_eer_init(void)
1032{
1033 int rc;
1034
666{
667 int rc;
668
1035 dasd_eer_workqueue = create_singlethread_workqueue("dasd_eer");
1036 if (!dasd_eer_workqueue) {
1037 MESSAGE(KERN_ERR , "%s", "dasd_eer_init could not "
1038 "create workqueue \n");
1039 rc = -ENOMEM;
1040 goto out;
1041 }
1042
1043 rc = dasd_register_eer_notifier(&dasd_eer_nb);
1044 if (rc) {
1045 MESSAGE(KERN_ERR, "%s", "dasd_eer_init could not "
1046 "register error reporting");
1047 goto queue;
1048 }
1049
1050 dasd_ioctl_no_register(THIS_MODULE, BIODASDEERSET, dasd_ioctl_set_eer);
1051 dasd_ioctl_no_register(THIS_MODULE, BIODASDEERGET, dasd_ioctl_get_eer);
1052
1053 /* we don't need our own character device,
1054 * so we just register as misc device */
1055 rc = misc_register(&dasd_eer_dev);
1056 if (rc) {
1057 MESSAGE(KERN_ERR, "%s", "dasd_eer_init could not "
1058 "register misc device");
669 rc = misc_register(&dasd_eer_dev);
670 if (rc) {
671 MESSAGE(KERN_ERR, "%s", "dasd_eer_init could not "
672 "register misc device");
1059 goto unregister;
673 return rc;
1060 }
1061
1062 return 0;
674 }
675
676 return 0;
1063
1064unregister:
1065 dasd_unregister_eer_notifier(&dasd_eer_nb);
1066 dasd_ioctl_no_unregister(THIS_MODULE, BIODASDEERSET,
1067 dasd_ioctl_set_eer);
1068 dasd_ioctl_no_unregister(THIS_MODULE, BIODASDEERGET,
1069 dasd_ioctl_get_eer);
1070queue:
1071 destroy_workqueue(dasd_eer_workqueue);
1072out:
1073 return rc;
1074
1075}
677}
1076module_init(dasd_eer_init);
1077
678
1078static void
1079__exit dasd_eer_exit(void)
679void __exit dasd_eer_exit(void)
1080{
680{
1081 dasd_unregister_eer_notifier(&dasd_eer_nb);
1082 dasd_ioctl_no_unregister(THIS_MODULE, BIODASDEERSET,
1083 dasd_ioctl_set_eer);
1084 dasd_ioctl_no_unregister(THIS_MODULE, BIODASDEERGET,
1085 dasd_ioctl_get_eer);
1086 destroy_workqueue(dasd_eer_workqueue);
1087
1088 WARN_ON(misc_deregister(&dasd_eer_dev) != 0);
1089}
681 WARN_ON(misc_deregister(&dasd_eer_dev) != 0);
682}
1090module_exit(dasd_eer_exit);