xref: /linux/arch/powerpc/kernel/rtas_flash.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  *  c 2001 PPC 64 Team, IBM Corp
3  *
4  *      This program is free software; you can redistribute it and/or
5  *      modify it under the terms of the GNU General Public License
6  *      as published by the Free Software Foundation; either version
7  *      2 of the License, or (at your option) any later version.
8  *
9  * /proc/powerpc/rtas/firmware_flash interface
10  *
11  * This file implements a firmware_flash interface to pump a firmware
12  * image into the kernel.  At reboot time rtas_restart() will see the
13  * firmware image and flash it as it reboots (see rtas.c).
14  */
15 
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/proc_fs.h>
20 #include <linux/reboot.h>
21 #include <asm/delay.h>
22 #include <asm/uaccess.h>
23 #include <asm/rtas.h>
24 
25 #define MODULE_VERS "1.0"
26 #define MODULE_NAME "rtas_flash"
27 
28 #define FIRMWARE_FLASH_NAME "firmware_flash"
29 #define FIRMWARE_UPDATE_NAME "firmware_update"
30 #define MANAGE_FLASH_NAME "manage_flash"
31 #define VALIDATE_FLASH_NAME "validate_flash"
32 
33 /* General RTAS Status Codes */
34 #define RTAS_RC_SUCCESS  0
35 #define RTAS_RC_HW_ERR	-1
36 #define RTAS_RC_BUSY	-2
37 
38 /* Flash image status values */
39 #define FLASH_AUTH           -9002 /* RTAS Not Service Authority Partition */
40 #define FLASH_NO_OP          -1099 /* No operation initiated by user */
41 #define FLASH_IMG_SHORT	     -1005 /* Flash image shorter than expected */
42 #define FLASH_IMG_BAD_LEN    -1004 /* Bad length value in flash list block */
43 #define FLASH_IMG_NULL_DATA  -1003 /* Bad data value in flash list block */
44 #define FLASH_IMG_READY      0     /* Firmware img ready for flash on reboot */
45 
46 /* Manage image status values */
47 #define MANAGE_AUTH          -9002 /* RTAS Not Service Authority Partition */
48 #define MANAGE_ACTIVE_ERR    -9001 /* RTAS Cannot Overwrite Active Img */
49 #define MANAGE_NO_OP         -1099 /* No operation initiated by user */
50 #define MANAGE_PARAM_ERR     -3    /* RTAS Parameter Error */
51 #define MANAGE_HW_ERR        -1    /* RTAS Hardware Error */
52 
53 /* Validate image status values */
54 #define VALIDATE_AUTH          -9002 /* RTAS Not Service Authority Partition */
55 #define VALIDATE_NO_OP         -1099 /* No operation initiated by the user */
56 #define VALIDATE_INCOMPLETE    -1002 /* User copied < VALIDATE_BUF_SIZE */
57 #define VALIDATE_READY	       -1001 /* Firmware image ready for validation */
58 #define VALIDATE_PARAM_ERR     -3    /* RTAS Parameter Error */
59 #define VALIDATE_HW_ERR        -1    /* RTAS Hardware Error */
60 #define VALIDATE_TMP_UPDATE    0     /* Validate Return Status */
61 #define VALIDATE_FLASH_AUTH    1     /* Validate Return Status */
62 #define VALIDATE_INVALID_IMG   2     /* Validate Return Status */
63 #define VALIDATE_CUR_UNKNOWN   3     /* Validate Return Status */
64 #define VALIDATE_TMP_COMMIT_DL 4     /* Validate Return Status */
65 #define VALIDATE_TMP_COMMIT    5     /* Validate Return Status */
66 #define VALIDATE_TMP_UPDATE_DL 6     /* Validate Return Status */
67 
68 /* ibm,manage-flash-image operation tokens */
69 #define RTAS_REJECT_TMP_IMG   0
70 #define RTAS_COMMIT_TMP_IMG   1
71 
72 /* Array sizes */
73 #define VALIDATE_BUF_SIZE 4096
74 #define RTAS_MSG_MAXLEN   64
75 
76 /* Quirk - RTAS requires 4k list length and block size */
77 #define RTAS_BLKLIST_LENGTH 4096
78 #define RTAS_BLK_SIZE 4096
79 
80 struct flash_block {
81 	char *data;
82 	unsigned long length;
83 };
84 
85 /* This struct is very similar but not identical to
86  * that needed by the rtas flash update.
87  * All we need to do for rtas is rewrite num_blocks
88  * into a version/length and translate the pointers
89  * to absolute.
90  */
91 #define FLASH_BLOCKS_PER_NODE ((RTAS_BLKLIST_LENGTH - 16) / sizeof(struct flash_block))
92 struct flash_block_list {
93 	unsigned long num_blocks;
94 	struct flash_block_list *next;
95 	struct flash_block blocks[FLASH_BLOCKS_PER_NODE];
96 };
97 
98 static struct flash_block_list *rtas_firmware_flash_list;
99 
100 /* Use slab cache to guarantee 4k alignment */
101 static struct kmem_cache *flash_block_cache = NULL;
102 
103 #define FLASH_BLOCK_LIST_VERSION (1UL)
104 
105 /* Local copy of the flash block list.
106  * We only allow one open of the flash proc file and create this
107  * list as we go.  The rtas_firmware_flash_list varable will be
108  * set once the data is fully read.
109  *
110  * For convenience as we build the list we use virtual addrs,
111  * we do not fill in the version number, and the length field
112  * is treated as the number of entries currently in the block
113  * (i.e. not a byte count).  This is all fixed when calling
114  * the flash routine.
115  */
116 
117 /* Status int must be first member of struct */
118 struct rtas_update_flash_t
119 {
120 	int status;			/* Flash update status */
121 	struct flash_block_list *flist; /* Local copy of flash block list */
122 };
123 
124 /* Status int must be first member of struct */
125 struct rtas_manage_flash_t
126 {
127 	int status;			/* Returned status */
128 	unsigned int op;		/* Reject or commit image */
129 };
130 
131 /* Status int must be first member of struct */
132 struct rtas_validate_flash_t
133 {
134 	int status;		 	/* Returned status */
135 	char buf[VALIDATE_BUF_SIZE]; 	/* Candidate image buffer */
136 	unsigned int buf_size;		/* Size of image buf */
137 	unsigned int update_results;	/* Update results token */
138 };
139 
140 static DEFINE_SPINLOCK(flash_file_open_lock);
141 static struct proc_dir_entry *firmware_flash_pde;
142 static struct proc_dir_entry *firmware_update_pde;
143 static struct proc_dir_entry *validate_pde;
144 static struct proc_dir_entry *manage_pde;
145 
146 /* Do simple sanity checks on the flash image. */
147 static int flash_list_valid(struct flash_block_list *flist)
148 {
149 	struct flash_block_list *f;
150 	int i;
151 	unsigned long block_size, image_size;
152 
153 	/* Paranoid self test here.  We also collect the image size. */
154 	image_size = 0;
155 	for (f = flist; f; f = f->next) {
156 		for (i = 0; i < f->num_blocks; i++) {
157 			if (f->blocks[i].data == NULL) {
158 				return FLASH_IMG_NULL_DATA;
159 			}
160 			block_size = f->blocks[i].length;
161 			if (block_size <= 0 || block_size > RTAS_BLK_SIZE) {
162 				return FLASH_IMG_BAD_LEN;
163 			}
164 			image_size += block_size;
165 		}
166 	}
167 
168 	if (image_size < (256 << 10)) {
169 		if (image_size < 2)
170 			return FLASH_NO_OP;
171 	}
172 
173 	printk(KERN_INFO "FLASH: flash image with %ld bytes stored for hardware flash on reboot\n", image_size);
174 
175 	return FLASH_IMG_READY;
176 }
177 
178 static void free_flash_list(struct flash_block_list *f)
179 {
180 	struct flash_block_list *next;
181 	int i;
182 
183 	while (f) {
184 		for (i = 0; i < f->num_blocks; i++)
185 			kmem_cache_free(flash_block_cache, f->blocks[i].data);
186 		next = f->next;
187 		kmem_cache_free(flash_block_cache, f);
188 		f = next;
189 	}
190 }
191 
192 static int rtas_flash_release(struct inode *inode, struct file *file)
193 {
194 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
195 	struct rtas_update_flash_t *uf;
196 
197 	uf = (struct rtas_update_flash_t *) dp->data;
198 	if (uf->flist) {
199 		/* File was opened in write mode for a new flash attempt */
200 		/* Clear saved list */
201 		if (rtas_firmware_flash_list) {
202 			free_flash_list(rtas_firmware_flash_list);
203 			rtas_firmware_flash_list = NULL;
204 		}
205 
206 		if (uf->status != FLASH_AUTH)
207 			uf->status = flash_list_valid(uf->flist);
208 
209 		if (uf->status == FLASH_IMG_READY)
210 			rtas_firmware_flash_list = uf->flist;
211 		else
212 			free_flash_list(uf->flist);
213 
214 		uf->flist = NULL;
215 	}
216 
217 	atomic_dec(&dp->count);
218 	return 0;
219 }
220 
221 static void get_flash_status_msg(int status, char *buf)
222 {
223 	char *msg;
224 
225 	switch (status) {
226 	case FLASH_AUTH:
227 		msg = "error: this partition does not have service authority\n";
228 		break;
229 	case FLASH_NO_OP:
230 		msg = "info: no firmware image for flash\n";
231 		break;
232 	case FLASH_IMG_SHORT:
233 		msg = "error: flash image short\n";
234 		break;
235 	case FLASH_IMG_BAD_LEN:
236 		msg = "error: internal error bad length\n";
237 		break;
238 	case FLASH_IMG_NULL_DATA:
239 		msg = "error: internal error null data\n";
240 		break;
241 	case FLASH_IMG_READY:
242 		msg = "ready: firmware image ready for flash on reboot\n";
243 		break;
244 	default:
245 		sprintf(buf, "error: unexpected status value %d\n", status);
246 		return;
247 	}
248 
249 	strcpy(buf, msg);
250 }
251 
252 /* Reading the proc file will show status (not the firmware contents) */
253 static ssize_t rtas_flash_read(struct file *file, char __user *buf,
254 			       size_t count, loff_t *ppos)
255 {
256 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
257 	struct rtas_update_flash_t *uf;
258 	char msg[RTAS_MSG_MAXLEN];
259 
260 	uf = dp->data;
261 
262 	if (!strcmp(dp->name, FIRMWARE_FLASH_NAME)) {
263 		get_flash_status_msg(uf->status, msg);
264 	} else {	   /* FIRMWARE_UPDATE_NAME */
265 		sprintf(msg, "%d\n", uf->status);
266 	}
267 
268 	return simple_read_from_buffer(buf, count, ppos, msg, strlen(msg));
269 }
270 
271 /* constructor for flash_block_cache */
272 void rtas_block_ctor(void *ptr)
273 {
274 	memset(ptr, 0, RTAS_BLK_SIZE);
275 }
276 
277 /* We could be much more efficient here.  But to keep this function
278  * simple we allocate a page to the block list no matter how small the
279  * count is.  If the system is low on memory it will be just as well
280  * that we fail....
281  */
282 static ssize_t rtas_flash_write(struct file *file, const char __user *buffer,
283 				size_t count, loff_t *off)
284 {
285 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
286 	struct rtas_update_flash_t *uf;
287 	char *p;
288 	int next_free;
289 	struct flash_block_list *fl;
290 
291 	uf = (struct rtas_update_flash_t *) dp->data;
292 
293 	if (uf->status == FLASH_AUTH || count == 0)
294 		return count;	/* discard data */
295 
296 	/* In the case that the image is not ready for flashing, the memory
297 	 * allocated for the block list will be freed upon the release of the
298 	 * proc file
299 	 */
300 	if (uf->flist == NULL) {
301 		uf->flist = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
302 		if (!uf->flist)
303 			return -ENOMEM;
304 	}
305 
306 	fl = uf->flist;
307 	while (fl->next)
308 		fl = fl->next; /* seek to last block_list for append */
309 	next_free = fl->num_blocks;
310 	if (next_free == FLASH_BLOCKS_PER_NODE) {
311 		/* Need to allocate another block_list */
312 		fl->next = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
313 		if (!fl->next)
314 			return -ENOMEM;
315 		fl = fl->next;
316 		next_free = 0;
317 	}
318 
319 	if (count > RTAS_BLK_SIZE)
320 		count = RTAS_BLK_SIZE;
321 	p = kmem_cache_alloc(flash_block_cache, GFP_KERNEL);
322 	if (!p)
323 		return -ENOMEM;
324 
325 	if(copy_from_user(p, buffer, count)) {
326 		kmem_cache_free(flash_block_cache, p);
327 		return -EFAULT;
328 	}
329 	fl->blocks[next_free].data = p;
330 	fl->blocks[next_free].length = count;
331 	fl->num_blocks++;
332 
333 	return count;
334 }
335 
336 static int rtas_excl_open(struct inode *inode, struct file *file)
337 {
338 	struct proc_dir_entry *dp = PDE(inode);
339 
340 	/* Enforce exclusive open with use count of PDE */
341 	spin_lock(&flash_file_open_lock);
342 	if (atomic_read(&dp->count) > 2) {
343 		spin_unlock(&flash_file_open_lock);
344 		return -EBUSY;
345 	}
346 
347 	atomic_inc(&dp->count);
348 	spin_unlock(&flash_file_open_lock);
349 
350 	return 0;
351 }
352 
353 static int rtas_excl_release(struct inode *inode, struct file *file)
354 {
355 	struct proc_dir_entry *dp = PDE(inode);
356 
357 	atomic_dec(&dp->count);
358 
359 	return 0;
360 }
361 
362 static void manage_flash(struct rtas_manage_flash_t *args_buf)
363 {
364 	s32 rc;
365 
366 	do {
367 		rc = rtas_call(rtas_token("ibm,manage-flash-image"), 1,
368 			       1, NULL, args_buf->op);
369 	} while (rtas_busy_delay(rc));
370 
371 	args_buf->status = rc;
372 }
373 
374 static ssize_t manage_flash_read(struct file *file, char __user *buf,
375 			       size_t count, loff_t *ppos)
376 {
377 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
378 	struct rtas_manage_flash_t *args_buf;
379 	char msg[RTAS_MSG_MAXLEN];
380 	int msglen;
381 
382 	args_buf = dp->data;
383 	if (args_buf == NULL)
384 		return 0;
385 
386 	msglen = sprintf(msg, "%d\n", args_buf->status);
387 
388 	return simple_read_from_buffer(buf, count, ppos, msg, msglen);
389 }
390 
391 static ssize_t manage_flash_write(struct file *file, const char __user *buf,
392 				size_t count, loff_t *off)
393 {
394 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
395 	struct rtas_manage_flash_t *args_buf;
396 	const char reject_str[] = "0";
397 	const char commit_str[] = "1";
398 	char stkbuf[10];
399 	int op;
400 
401 	args_buf = (struct rtas_manage_flash_t *) dp->data;
402 	if ((args_buf->status == MANAGE_AUTH) || (count == 0))
403 		return count;
404 
405 	op = -1;
406 	if (buf) {
407 		if (count > 9) count = 9;
408 		if (copy_from_user (stkbuf, buf, count)) {
409 			return -EFAULT;
410 		}
411 		if (strncmp(stkbuf, reject_str, strlen(reject_str)) == 0)
412 			op = RTAS_REJECT_TMP_IMG;
413 		else if (strncmp(stkbuf, commit_str, strlen(commit_str)) == 0)
414 			op = RTAS_COMMIT_TMP_IMG;
415 	}
416 
417 	if (op == -1)   /* buf is empty, or contains invalid string */
418 		return -EINVAL;
419 
420 	args_buf->op = op;
421 	manage_flash(args_buf);
422 
423 	return count;
424 }
425 
426 static void validate_flash(struct rtas_validate_flash_t *args_buf)
427 {
428 	int token = rtas_token("ibm,validate-flash-image");
429 	int update_results;
430 	s32 rc;
431 
432 	rc = 0;
433 	do {
434 		spin_lock(&rtas_data_buf_lock);
435 		memcpy(rtas_data_buf, args_buf->buf, VALIDATE_BUF_SIZE);
436 		rc = rtas_call(token, 2, 2, &update_results,
437 			       (u32) __pa(rtas_data_buf), args_buf->buf_size);
438 		memcpy(args_buf->buf, rtas_data_buf, VALIDATE_BUF_SIZE);
439 		spin_unlock(&rtas_data_buf_lock);
440 	} while (rtas_busy_delay(rc));
441 
442 	args_buf->status = rc;
443 	args_buf->update_results = update_results;
444 }
445 
446 static int get_validate_flash_msg(struct rtas_validate_flash_t *args_buf,
447 		                   char *msg)
448 {
449 	int n;
450 
451 	if (args_buf->status >= VALIDATE_TMP_UPDATE) {
452 		n = sprintf(msg, "%d\n", args_buf->update_results);
453 		if ((args_buf->update_results >= VALIDATE_CUR_UNKNOWN) ||
454 		    (args_buf->update_results == VALIDATE_TMP_UPDATE))
455 			n += sprintf(msg + n, "%s\n", args_buf->buf);
456 	} else {
457 		n = sprintf(msg, "%d\n", args_buf->status);
458 	}
459 	return n;
460 }
461 
462 static ssize_t validate_flash_read(struct file *file, char __user *buf,
463 			       size_t count, loff_t *ppos)
464 {
465 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
466 	struct rtas_validate_flash_t *args_buf;
467 	char msg[RTAS_MSG_MAXLEN];
468 	int msglen;
469 
470 	args_buf = dp->data;
471 
472 	msglen = get_validate_flash_msg(args_buf, msg);
473 
474 	return simple_read_from_buffer(buf, count, ppos, msg, msglen);
475 }
476 
477 static ssize_t validate_flash_write(struct file *file, const char __user *buf,
478 				    size_t count, loff_t *off)
479 {
480 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
481 	struct rtas_validate_flash_t *args_buf;
482 	int rc;
483 
484 	args_buf = (struct rtas_validate_flash_t *) dp->data;
485 
486 	if (dp->data == NULL) {
487 		dp->data = kmalloc(sizeof(struct rtas_validate_flash_t),
488 				GFP_KERNEL);
489 		if (dp->data == NULL)
490 			return -ENOMEM;
491 	}
492 
493 	/* We are only interested in the first 4K of the
494 	 * candidate image */
495 	if ((*off >= VALIDATE_BUF_SIZE) ||
496 		(args_buf->status == VALIDATE_AUTH)) {
497 		*off += count;
498 		return count;
499 	}
500 
501 	if (*off + count >= VALIDATE_BUF_SIZE)  {
502 		count = VALIDATE_BUF_SIZE - *off;
503 		args_buf->status = VALIDATE_READY;
504 	} else {
505 		args_buf->status = VALIDATE_INCOMPLETE;
506 	}
507 
508 	if (!access_ok(VERIFY_READ, buf, count)) {
509 		rc = -EFAULT;
510 		goto done;
511 	}
512 	if (copy_from_user(args_buf->buf + *off, buf, count)) {
513 		rc = -EFAULT;
514 		goto done;
515 	}
516 
517 	*off += count;
518 	rc = count;
519 done:
520 	if (rc < 0) {
521 		kfree(dp->data);
522 		dp->data = NULL;
523 	}
524 	return rc;
525 }
526 
527 static int validate_flash_release(struct inode *inode, struct file *file)
528 {
529 	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
530 	struct rtas_validate_flash_t *args_buf;
531 
532 	args_buf = (struct rtas_validate_flash_t *) dp->data;
533 
534 	if (args_buf->status == VALIDATE_READY) {
535 		args_buf->buf_size = VALIDATE_BUF_SIZE;
536 		validate_flash(args_buf);
537 	}
538 
539 	/* The matching atomic_inc was in rtas_excl_open() */
540 	atomic_dec(&dp->count);
541 
542 	return 0;
543 }
544 
545 static void rtas_flash_firmware(int reboot_type)
546 {
547 	unsigned long image_size;
548 	struct flash_block_list *f, *next, *flist;
549 	unsigned long rtas_block_list;
550 	int i, status, update_token;
551 
552 	if (rtas_firmware_flash_list == NULL)
553 		return;		/* nothing to do */
554 
555 	if (reboot_type != SYS_RESTART) {
556 		printk(KERN_ALERT "FLASH: firmware flash requires a reboot\n");
557 		printk(KERN_ALERT "FLASH: the firmware image will NOT be flashed\n");
558 		return;
559 	}
560 
561 	update_token = rtas_token("ibm,update-flash-64-and-reboot");
562 	if (update_token == RTAS_UNKNOWN_SERVICE) {
563 		printk(KERN_ALERT "FLASH: ibm,update-flash-64-and-reboot "
564 		       "is not available -- not a service partition?\n");
565 		printk(KERN_ALERT "FLASH: firmware will not be flashed\n");
566 		return;
567 	}
568 
569 	/*
570 	 * Just before starting the firmware flash, cancel the event scan work
571 	 * to avoid any soft lockup issues.
572 	 */
573 	rtas_cancel_event_scan();
574 
575 	/*
576 	 * NOTE: the "first" block must be under 4GB, so we create
577 	 * an entry with no data blocks in the reserved buffer in
578 	 * the kernel data segment.
579 	 */
580 	spin_lock(&rtas_data_buf_lock);
581 	flist = (struct flash_block_list *)&rtas_data_buf[0];
582 	flist->num_blocks = 0;
583 	flist->next = rtas_firmware_flash_list;
584 	rtas_block_list = __pa(flist);
585 	if (rtas_block_list >= 4UL*1024*1024*1024) {
586 		printk(KERN_ALERT "FLASH: kernel bug...flash list header addr above 4GB\n");
587 		spin_unlock(&rtas_data_buf_lock);
588 		return;
589 	}
590 
591 	printk(KERN_ALERT "FLASH: preparing saved firmware image for flash\n");
592 	/* Update the block_list in place. */
593 	rtas_firmware_flash_list = NULL; /* too hard to backout on error */
594 	image_size = 0;
595 	for (f = flist; f; f = next) {
596 		/* Translate data addrs to absolute */
597 		for (i = 0; i < f->num_blocks; i++) {
598 			f->blocks[i].data = (char *)__pa(f->blocks[i].data);
599 			image_size += f->blocks[i].length;
600 		}
601 		next = f->next;
602 		/* Don't translate NULL pointer for last entry */
603 		if (f->next)
604 			f->next = (struct flash_block_list *)__pa(f->next);
605 		else
606 			f->next = NULL;
607 		/* make num_blocks into the version/length field */
608 		f->num_blocks = (FLASH_BLOCK_LIST_VERSION << 56) | ((f->num_blocks+1)*16);
609 	}
610 
611 	printk(KERN_ALERT "FLASH: flash image is %ld bytes\n", image_size);
612 	printk(KERN_ALERT "FLASH: performing flash and reboot\n");
613 	rtas_progress("Flashing        \n", 0x0);
614 	rtas_progress("Please Wait...  ", 0x0);
615 	printk(KERN_ALERT "FLASH: this will take several minutes.  Do not power off!\n");
616 	status = rtas_call(update_token, 1, 1, NULL, rtas_block_list);
617 	switch (status) {	/* should only get "bad" status */
618 	    case 0:
619 		printk(KERN_ALERT "FLASH: success\n");
620 		break;
621 	    case -1:
622 		printk(KERN_ALERT "FLASH: hardware error.  Firmware may not be not flashed\n");
623 		break;
624 	    case -3:
625 		printk(KERN_ALERT "FLASH: image is corrupt or not correct for this platform.  Firmware not flashed\n");
626 		break;
627 	    case -4:
628 		printk(KERN_ALERT "FLASH: flash failed when partially complete.  System may not reboot\n");
629 		break;
630 	    default:
631 		printk(KERN_ALERT "FLASH: unknown flash return code %d\n", status);
632 		break;
633 	}
634 	spin_unlock(&rtas_data_buf_lock);
635 }
636 
637 static void remove_flash_pde(struct proc_dir_entry *dp)
638 {
639 	if (dp) {
640 		kfree(dp->data);
641 		remove_proc_entry(dp->name, dp->parent);
642 	}
643 }
644 
645 static int initialize_flash_pde_data(const char *rtas_call_name,
646 				     size_t buf_size,
647 				     struct proc_dir_entry *dp)
648 {
649 	int *status;
650 	int token;
651 
652 	dp->data = kzalloc(buf_size, GFP_KERNEL);
653 	if (dp->data == NULL)
654 		return -ENOMEM;
655 
656 	/*
657 	 * This code assumes that the status int is the first member of the
658 	 * struct
659 	 */
660 	status = (int *) dp->data;
661 	token = rtas_token(rtas_call_name);
662 	if (token == RTAS_UNKNOWN_SERVICE)
663 		*status = FLASH_AUTH;
664 	else
665 		*status = FLASH_NO_OP;
666 
667 	return 0;
668 }
669 
670 static struct proc_dir_entry *create_flash_pde(const char *filename,
671 					       const struct file_operations *fops)
672 {
673 	return proc_create(filename, S_IRUSR | S_IWUSR, NULL, fops);
674 }
675 
676 static const struct file_operations rtas_flash_operations = {
677 	.owner		= THIS_MODULE,
678 	.read		= rtas_flash_read,
679 	.write		= rtas_flash_write,
680 	.open		= rtas_excl_open,
681 	.release	= rtas_flash_release,
682 	.llseek		= default_llseek,
683 };
684 
685 static const struct file_operations manage_flash_operations = {
686 	.owner		= THIS_MODULE,
687 	.read		= manage_flash_read,
688 	.write		= manage_flash_write,
689 	.open		= rtas_excl_open,
690 	.release	= rtas_excl_release,
691 	.llseek		= default_llseek,
692 };
693 
694 static const struct file_operations validate_flash_operations = {
695 	.owner		= THIS_MODULE,
696 	.read		= validate_flash_read,
697 	.write		= validate_flash_write,
698 	.open		= rtas_excl_open,
699 	.release	= validate_flash_release,
700 	.llseek		= default_llseek,
701 };
702 
703 static int __init rtas_flash_init(void)
704 {
705 	int rc;
706 
707 	if (rtas_token("ibm,update-flash-64-and-reboot") ==
708 		       RTAS_UNKNOWN_SERVICE) {
709 		pr_info("rtas_flash: no firmware flash support\n");
710 		return 1;
711 	}
712 
713 	firmware_flash_pde = create_flash_pde("powerpc/rtas/"
714 					      FIRMWARE_FLASH_NAME,
715 					      &rtas_flash_operations);
716 	if (firmware_flash_pde == NULL) {
717 		rc = -ENOMEM;
718 		goto cleanup;
719 	}
720 
721 	rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
722 			 	       sizeof(struct rtas_update_flash_t),
723 				       firmware_flash_pde);
724 	if (rc != 0)
725 		goto cleanup;
726 
727 	firmware_update_pde = create_flash_pde("powerpc/rtas/"
728 					       FIRMWARE_UPDATE_NAME,
729 					       &rtas_flash_operations);
730 	if (firmware_update_pde == NULL) {
731 		rc = -ENOMEM;
732 		goto cleanup;
733 	}
734 
735 	rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
736 			 	       sizeof(struct rtas_update_flash_t),
737 				       firmware_update_pde);
738 	if (rc != 0)
739 		goto cleanup;
740 
741 	validate_pde = create_flash_pde("powerpc/rtas/" VALIDATE_FLASH_NAME,
742 			      		&validate_flash_operations);
743 	if (validate_pde == NULL) {
744 		rc = -ENOMEM;
745 		goto cleanup;
746 	}
747 
748 	rc = initialize_flash_pde_data("ibm,validate-flash-image",
749 		                       sizeof(struct rtas_validate_flash_t),
750 				       validate_pde);
751 	if (rc != 0)
752 		goto cleanup;
753 
754 	manage_pde = create_flash_pde("powerpc/rtas/" MANAGE_FLASH_NAME,
755 				      &manage_flash_operations);
756 	if (manage_pde == NULL) {
757 		rc = -ENOMEM;
758 		goto cleanup;
759 	}
760 
761 	rc = initialize_flash_pde_data("ibm,manage-flash-image",
762 			               sizeof(struct rtas_manage_flash_t),
763 				       manage_pde);
764 	if (rc != 0)
765 		goto cleanup;
766 
767 	rtas_flash_term_hook = rtas_flash_firmware;
768 
769 	flash_block_cache = kmem_cache_create("rtas_flash_cache",
770 				RTAS_BLK_SIZE, RTAS_BLK_SIZE, 0,
771 				rtas_block_ctor);
772 	if (!flash_block_cache) {
773 		printk(KERN_ERR "%s: failed to create block cache\n",
774 				__func__);
775 		rc = -ENOMEM;
776 		goto cleanup;
777 	}
778 	return 0;
779 
780 cleanup:
781 	remove_flash_pde(firmware_flash_pde);
782 	remove_flash_pde(firmware_update_pde);
783 	remove_flash_pde(validate_pde);
784 	remove_flash_pde(manage_pde);
785 
786 	return rc;
787 }
788 
789 static void __exit rtas_flash_cleanup(void)
790 {
791 	rtas_flash_term_hook = NULL;
792 
793 	if (flash_block_cache)
794 		kmem_cache_destroy(flash_block_cache);
795 
796 	remove_flash_pde(firmware_flash_pde);
797 	remove_flash_pde(firmware_update_pde);
798 	remove_flash_pde(validate_pde);
799 	remove_flash_pde(manage_pde);
800 }
801 
802 module_init(rtas_flash_init);
803 module_exit(rtas_flash_cleanup);
804 MODULE_LICENSE("GPL");
805