ia64/linux-2.6.18-xen.hg

view drivers/mtd/mtdchar.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /*
2 * $Id: mtdchar.c,v 1.76 2005/11/07 11:14:20 gleixner Exp $
3 *
4 * Character-device access to raw MTD devices.
5 *
6 */
8 #include <linux/device.h>
9 #include <linux/fs.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/sched.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/compatmac.h>
19 #include <asm/uaccess.h>
21 static struct class *mtd_class;
23 static void mtd_notify_add(struct mtd_info* mtd)
24 {
25 if (!mtd)
26 return;
28 class_device_create(mtd_class, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
29 NULL, "mtd%d", mtd->index);
31 class_device_create(mtd_class, NULL,
32 MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
33 NULL, "mtd%dro", mtd->index);
34 }
36 static void mtd_notify_remove(struct mtd_info* mtd)
37 {
38 if (!mtd)
39 return;
41 class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2));
42 class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1));
43 }
45 static struct mtd_notifier notifier = {
46 .add = mtd_notify_add,
47 .remove = mtd_notify_remove,
48 };
50 /*
51 * Data structure to hold the pointer to the mtd device as well
52 * as mode information ofr various use cases.
53 */
54 struct mtd_file_info {
55 struct mtd_info *mtd;
56 enum mtd_file_modes mode;
57 };
59 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
60 {
61 struct mtd_file_info *mfi = file->private_data;
62 struct mtd_info *mtd = mfi->mtd;
64 switch (orig) {
65 case SEEK_SET:
66 break;
67 case SEEK_CUR:
68 offset += file->f_pos;
69 break;
70 case SEEK_END:
71 offset += mtd->size;
72 break;
73 default:
74 return -EINVAL;
75 }
77 if (offset >= 0 && offset <= mtd->size)
78 return file->f_pos = offset;
80 return -EINVAL;
81 }
85 static int mtd_open(struct inode *inode, struct file *file)
86 {
87 int minor = iminor(inode);
88 int devnum = minor >> 1;
89 struct mtd_info *mtd;
90 struct mtd_file_info *mfi;
92 DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
94 if (devnum >= MAX_MTD_DEVICES)
95 return -ENODEV;
97 /* You can't open the RO devices RW */
98 if ((file->f_mode & 2) && (minor & 1))
99 return -EACCES;
101 mtd = get_mtd_device(NULL, devnum);
103 if (!mtd)
104 return -ENODEV;
106 if (MTD_ABSENT == mtd->type) {
107 put_mtd_device(mtd);
108 return -ENODEV;
109 }
111 /* You can't open it RW if it's not a writeable device */
112 if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
113 put_mtd_device(mtd);
114 return -EACCES;
115 }
117 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
118 if (!mfi) {
119 put_mtd_device(mtd);
120 return -ENOMEM;
121 }
122 mfi->mtd = mtd;
123 file->private_data = mfi;
125 return 0;
126 } /* mtd_open */
128 /*====================================================================*/
130 static int mtd_close(struct inode *inode, struct file *file)
131 {
132 struct mtd_file_info *mfi = file->private_data;
133 struct mtd_info *mtd = mfi->mtd;
135 DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
137 if (mtd->sync)
138 mtd->sync(mtd);
140 put_mtd_device(mtd);
141 file->private_data = NULL;
142 kfree(mfi);
144 return 0;
145 } /* mtd_close */
147 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
148 userspace buffer down and use it directly with readv/writev.
149 */
150 #define MAX_KMALLOC_SIZE 0x20000
152 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
153 {
154 struct mtd_file_info *mfi = file->private_data;
155 struct mtd_info *mtd = mfi->mtd;
156 size_t retlen=0;
157 size_t total_retlen=0;
158 int ret=0;
159 int len;
160 char *kbuf;
162 DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
164 if (*ppos + count > mtd->size)
165 count = mtd->size - *ppos;
167 if (!count)
168 return 0;
170 /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
171 and pass them directly to the MTD functions */
173 if (count > MAX_KMALLOC_SIZE)
174 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
175 else
176 kbuf=kmalloc(count, GFP_KERNEL);
178 if (!kbuf)
179 return -ENOMEM;
181 while (count) {
183 if (count > MAX_KMALLOC_SIZE)
184 len = MAX_KMALLOC_SIZE;
185 else
186 len = count;
188 switch (mfi->mode) {
189 case MTD_MODE_OTP_FACTORY:
190 ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
191 break;
192 case MTD_MODE_OTP_USER:
193 ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
194 break;
195 case MTD_MODE_RAW:
196 {
197 struct mtd_oob_ops ops;
199 ops.mode = MTD_OOB_RAW;
200 ops.datbuf = kbuf;
201 ops.oobbuf = NULL;
202 ops.len = len;
204 ret = mtd->read_oob(mtd, *ppos, &ops);
205 retlen = ops.retlen;
206 break;
207 }
208 default:
209 ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
210 }
211 /* Nand returns -EBADMSG on ecc errors, but it returns
212 * the data. For our userspace tools it is important
213 * to dump areas with ecc errors !
214 * For kernel internal usage it also might return -EUCLEAN
215 * to signal the caller that a bitflip has occured and has
216 * been corrected by the ECC algorithm.
217 * Userspace software which accesses NAND this way
218 * must be aware of the fact that it deals with NAND
219 */
220 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
221 *ppos += retlen;
222 if (copy_to_user(buf, kbuf, retlen)) {
223 kfree(kbuf);
224 return -EFAULT;
225 }
226 else
227 total_retlen += retlen;
229 count -= retlen;
230 buf += retlen;
231 if (retlen == 0)
232 count = 0;
233 }
234 else {
235 kfree(kbuf);
236 return ret;
237 }
239 }
241 kfree(kbuf);
242 return total_retlen;
243 } /* mtd_read */
245 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
246 {
247 struct mtd_file_info *mfi = file->private_data;
248 struct mtd_info *mtd = mfi->mtd;
249 char *kbuf;
250 size_t retlen;
251 size_t total_retlen=0;
252 int ret=0;
253 int len;
255 DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
257 if (*ppos == mtd->size)
258 return -ENOSPC;
260 if (*ppos + count > mtd->size)
261 count = mtd->size - *ppos;
263 if (!count)
264 return 0;
266 if (count > MAX_KMALLOC_SIZE)
267 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
268 else
269 kbuf=kmalloc(count, GFP_KERNEL);
271 if (!kbuf)
272 return -ENOMEM;
274 while (count) {
276 if (count > MAX_KMALLOC_SIZE)
277 len = MAX_KMALLOC_SIZE;
278 else
279 len = count;
281 if (copy_from_user(kbuf, buf, len)) {
282 kfree(kbuf);
283 return -EFAULT;
284 }
286 switch (mfi->mode) {
287 case MTD_MODE_OTP_FACTORY:
288 ret = -EROFS;
289 break;
290 case MTD_MODE_OTP_USER:
291 if (!mtd->write_user_prot_reg) {
292 ret = -EOPNOTSUPP;
293 break;
294 }
295 ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
296 break;
298 case MTD_MODE_RAW:
299 {
300 struct mtd_oob_ops ops;
302 ops.mode = MTD_OOB_RAW;
303 ops.datbuf = kbuf;
304 ops.oobbuf = NULL;
305 ops.len = len;
307 ret = mtd->write_oob(mtd, *ppos, &ops);
308 retlen = ops.retlen;
309 break;
310 }
312 default:
313 ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
314 }
315 if (!ret) {
316 *ppos += retlen;
317 total_retlen += retlen;
318 count -= retlen;
319 buf += retlen;
320 }
321 else {
322 kfree(kbuf);
323 return ret;
324 }
325 }
327 kfree(kbuf);
328 return total_retlen;
329 } /* mtd_write */
331 /*======================================================================
333 IOCTL calls for getting device parameters.
335 ======================================================================*/
336 static void mtdchar_erase_callback (struct erase_info *instr)
337 {
338 wake_up((wait_queue_head_t *)instr->priv);
339 }
341 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
342 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
343 {
344 struct mtd_info *mtd = mfi->mtd;
345 int ret = 0;
347 switch (mode) {
348 case MTD_OTP_FACTORY:
349 if (!mtd->read_fact_prot_reg)
350 ret = -EOPNOTSUPP;
351 else
352 mfi->mode = MTD_MODE_OTP_FACTORY;
353 break;
354 case MTD_OTP_USER:
355 if (!mtd->read_fact_prot_reg)
356 ret = -EOPNOTSUPP;
357 else
358 mfi->mode = MTD_MODE_OTP_USER;
359 break;
360 default:
361 ret = -EINVAL;
362 case MTD_OTP_OFF:
363 break;
364 }
365 return ret;
366 }
367 #else
368 # define otp_select_filemode(f,m) -EOPNOTSUPP
369 #endif
371 static int mtd_ioctl(struct inode *inode, struct file *file,
372 u_int cmd, u_long arg)
373 {
374 struct mtd_file_info *mfi = file->private_data;
375 struct mtd_info *mtd = mfi->mtd;
376 void __user *argp = (void __user *)arg;
377 int ret = 0;
378 u_long size;
379 struct mtd_info_user info;
381 DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
383 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
384 if (cmd & IOC_IN) {
385 if (!access_ok(VERIFY_READ, argp, size))
386 return -EFAULT;
387 }
388 if (cmd & IOC_OUT) {
389 if (!access_ok(VERIFY_WRITE, argp, size))
390 return -EFAULT;
391 }
393 switch (cmd) {
394 case MEMGETREGIONCOUNT:
395 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
396 return -EFAULT;
397 break;
399 case MEMGETREGIONINFO:
400 {
401 struct region_info_user ur;
403 if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
404 return -EFAULT;
406 if (ur.regionindex >= mtd->numeraseregions)
407 return -EINVAL;
408 if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
409 sizeof(struct mtd_erase_region_info)))
410 return -EFAULT;
411 break;
412 }
414 case MEMGETINFO:
415 info.type = mtd->type;
416 info.flags = mtd->flags;
417 info.size = mtd->size;
418 info.erasesize = mtd->erasesize;
419 info.writesize = mtd->writesize;
420 info.oobsize = mtd->oobsize;
421 info.ecctype = mtd->ecctype;
422 info.eccsize = mtd->eccsize;
423 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
424 return -EFAULT;
425 break;
427 case MEMERASE:
428 {
429 struct erase_info *erase;
431 if(!(file->f_mode & 2))
432 return -EPERM;
434 erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
435 if (!erase)
436 ret = -ENOMEM;
437 else {
438 wait_queue_head_t waitq;
439 DECLARE_WAITQUEUE(wait, current);
441 init_waitqueue_head(&waitq);
443 memset (erase,0,sizeof(struct erase_info));
444 if (copy_from_user(&erase->addr, argp,
445 sizeof(struct erase_info_user))) {
446 kfree(erase);
447 return -EFAULT;
448 }
449 erase->mtd = mtd;
450 erase->callback = mtdchar_erase_callback;
451 erase->priv = (unsigned long)&waitq;
453 /*
454 FIXME: Allow INTERRUPTIBLE. Which means
455 not having the wait_queue head on the stack.
457 If the wq_head is on the stack, and we
458 leave because we got interrupted, then the
459 wq_head is no longer there when the
460 callback routine tries to wake us up.
461 */
462 ret = mtd->erase(mtd, erase);
463 if (!ret) {
464 set_current_state(TASK_UNINTERRUPTIBLE);
465 add_wait_queue(&waitq, &wait);
466 if (erase->state != MTD_ERASE_DONE &&
467 erase->state != MTD_ERASE_FAILED)
468 schedule();
469 remove_wait_queue(&waitq, &wait);
470 set_current_state(TASK_RUNNING);
472 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
473 }
474 kfree(erase);
475 }
476 break;
477 }
479 case MEMWRITEOOB:
480 {
481 struct mtd_oob_buf buf;
482 struct mtd_oob_ops ops;
484 if(!(file->f_mode & 2))
485 return -EPERM;
487 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
488 return -EFAULT;
490 if (buf.length > 4096)
491 return -EINVAL;
493 if (!mtd->write_oob)
494 ret = -EOPNOTSUPP;
495 else
496 ret = access_ok(VERIFY_READ, buf.ptr,
497 buf.length) ? 0 : EFAULT;
499 if (ret)
500 return ret;
502 ops.len = buf.length;
503 ops.ooblen = buf.length;
504 ops.ooboffs = buf.start & (mtd->oobsize - 1);
505 ops.datbuf = NULL;
506 ops.mode = MTD_OOB_PLACE;
508 if (ops.ooboffs && ops.len > (mtd->oobsize - ops.ooboffs))
509 return -EINVAL;
511 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
512 if (!ops.oobbuf)
513 return -ENOMEM;
515 if (copy_from_user(ops.oobbuf, buf.ptr, buf.length)) {
516 kfree(ops.oobbuf);
517 return -EFAULT;
518 }
520 buf.start &= ~(mtd->oobsize - 1);
521 ret = mtd->write_oob(mtd, buf.start, &ops);
523 if (copy_to_user(argp + sizeof(uint32_t), &ops.retlen,
524 sizeof(uint32_t)))
525 ret = -EFAULT;
527 kfree(ops.oobbuf);
528 break;
530 }
532 case MEMREADOOB:
533 {
534 struct mtd_oob_buf buf;
535 struct mtd_oob_ops ops;
537 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
538 return -EFAULT;
540 if (buf.length > 4096)
541 return -EINVAL;
543 if (!mtd->read_oob)
544 ret = -EOPNOTSUPP;
545 else
546 ret = access_ok(VERIFY_WRITE, buf.ptr,
547 buf.length) ? 0 : -EFAULT;
548 if (ret)
549 return ret;
551 ops.len = buf.length;
552 ops.ooblen = buf.length;
553 ops.ooboffs = buf.start & (mtd->oobsize - 1);
554 ops.datbuf = NULL;
555 ops.mode = MTD_OOB_PLACE;
557 if (ops.ooboffs && ops.len > (mtd->oobsize - ops.ooboffs))
558 return -EINVAL;
560 ops.oobbuf = kmalloc(buf.length, GFP_KERNEL);
561 if (!ops.oobbuf)
562 return -ENOMEM;
564 buf.start &= ~(mtd->oobsize - 1);
565 ret = mtd->read_oob(mtd, buf.start, &ops);
567 if (put_user(ops.retlen, (uint32_t __user *)argp))
568 ret = -EFAULT;
569 else if (ops.retlen && copy_to_user(buf.ptr, ops.oobbuf,
570 ops.retlen))
571 ret = -EFAULT;
573 kfree(ops.oobbuf);
574 break;
575 }
577 case MEMLOCK:
578 {
579 struct erase_info_user info;
581 if (copy_from_user(&info, argp, sizeof(info)))
582 return -EFAULT;
584 if (!mtd->lock)
585 ret = -EOPNOTSUPP;
586 else
587 ret = mtd->lock(mtd, info.start, info.length);
588 break;
589 }
591 case MEMUNLOCK:
592 {
593 struct erase_info_user info;
595 if (copy_from_user(&info, argp, sizeof(info)))
596 return -EFAULT;
598 if (!mtd->unlock)
599 ret = -EOPNOTSUPP;
600 else
601 ret = mtd->unlock(mtd, info.start, info.length);
602 break;
603 }
605 /* Legacy interface */
606 case MEMGETOOBSEL:
607 {
608 struct nand_oobinfo oi;
610 if (!mtd->ecclayout)
611 return -EOPNOTSUPP;
612 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
613 return -EINVAL;
615 oi.useecc = MTD_NANDECC_AUTOPLACE;
616 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
617 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
618 sizeof(oi.oobfree));
620 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
621 return -EFAULT;
622 break;
623 }
625 case MEMGETBADBLOCK:
626 {
627 loff_t offs;
629 if (copy_from_user(&offs, argp, sizeof(loff_t)))
630 return -EFAULT;
631 if (!mtd->block_isbad)
632 ret = -EOPNOTSUPP;
633 else
634 return mtd->block_isbad(mtd, offs);
635 break;
636 }
638 case MEMSETBADBLOCK:
639 {
640 loff_t offs;
642 if (copy_from_user(&offs, argp, sizeof(loff_t)))
643 return -EFAULT;
644 if (!mtd->block_markbad)
645 ret = -EOPNOTSUPP;
646 else
647 return mtd->block_markbad(mtd, offs);
648 break;
649 }
651 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
652 case OTPSELECT:
653 {
654 int mode;
655 if (copy_from_user(&mode, argp, sizeof(int)))
656 return -EFAULT;
658 mfi->mode = MTD_MODE_NORMAL;
660 ret = otp_select_filemode(mfi, mode);
662 file->f_pos = 0;
663 break;
664 }
666 case OTPGETREGIONCOUNT:
667 case OTPGETREGIONINFO:
668 {
669 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
670 if (!buf)
671 return -ENOMEM;
672 ret = -EOPNOTSUPP;
673 switch (mfi->mode) {
674 case MTD_MODE_OTP_FACTORY:
675 if (mtd->get_fact_prot_info)
676 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
677 break;
678 case MTD_MODE_OTP_USER:
679 if (mtd->get_user_prot_info)
680 ret = mtd->get_user_prot_info(mtd, buf, 4096);
681 break;
682 default:
683 break;
684 }
685 if (ret >= 0) {
686 if (cmd == OTPGETREGIONCOUNT) {
687 int nbr = ret / sizeof(struct otp_info);
688 ret = copy_to_user(argp, &nbr, sizeof(int));
689 } else
690 ret = copy_to_user(argp, buf, ret);
691 if (ret)
692 ret = -EFAULT;
693 }
694 kfree(buf);
695 break;
696 }
698 case OTPLOCK:
699 {
700 struct otp_info info;
702 if (mfi->mode != MTD_MODE_OTP_USER)
703 return -EINVAL;
704 if (copy_from_user(&info, argp, sizeof(info)))
705 return -EFAULT;
706 if (!mtd->lock_user_prot_reg)
707 return -EOPNOTSUPP;
708 ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
709 break;
710 }
711 #endif
713 case ECCGETLAYOUT:
714 {
715 if (!mtd->ecclayout)
716 return -EOPNOTSUPP;
718 if (copy_to_user(argp, &mtd->ecclayout,
719 sizeof(struct nand_ecclayout)))
720 return -EFAULT;
721 break;
722 }
724 case ECCGETSTATS:
725 {
726 if (copy_to_user(argp, &mtd->ecc_stats,
727 sizeof(struct mtd_ecc_stats)))
728 return -EFAULT;
729 break;
730 }
732 case MTDFILEMODE:
733 {
734 mfi->mode = 0;
736 switch(arg) {
737 case MTD_MODE_OTP_FACTORY:
738 case MTD_MODE_OTP_USER:
739 ret = otp_select_filemode(mfi, arg);
740 break;
742 case MTD_MODE_RAW:
743 if (!mtd->read_oob || !mtd->write_oob)
744 return -EOPNOTSUPP;
745 mfi->mode = arg;
747 case MTD_MODE_NORMAL:
748 break;
749 default:
750 ret = -EINVAL;
751 }
752 file->f_pos = 0;
753 break;
754 }
756 default:
757 ret = -ENOTTY;
758 }
760 return ret;
761 } /* memory_ioctl */
763 static struct file_operations mtd_fops = {
764 .owner = THIS_MODULE,
765 .llseek = mtd_lseek,
766 .read = mtd_read,
767 .write = mtd_write,
768 .ioctl = mtd_ioctl,
769 .open = mtd_open,
770 .release = mtd_close,
771 };
773 static int __init init_mtdchar(void)
774 {
775 if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
776 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
777 MTD_CHAR_MAJOR);
778 return -EAGAIN;
779 }
781 mtd_class = class_create(THIS_MODULE, "mtd");
783 if (IS_ERR(mtd_class)) {
784 printk(KERN_ERR "Error creating mtd class.\n");
785 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
786 return PTR_ERR(mtd_class);
787 }
789 register_mtd_user(&notifier);
790 return 0;
791 }
793 static void __exit cleanup_mtdchar(void)
794 {
795 unregister_mtd_user(&notifier);
796 class_destroy(mtd_class);
797 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
798 }
800 module_init(init_mtdchar);
801 module_exit(cleanup_mtdchar);
804 MODULE_LICENSE("GPL");
805 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
806 MODULE_DESCRIPTION("Direct character-device access to MTD devices");