2 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 #include <linux/device.h>
23 #include <linux/err.h>
24 #include <linux/init.h>
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/sched.h>
29 #include <linux/mutex.h>
30 #include <linux/backing-dev.h>
31 #include <linux/compat.h>
32 #include <linux/mount.h>
34 #include <linux/mtd/mtd.h>
35 #include <linux/mtd/map.h>
37 #include <asm/uaccess.h>
39 #define MTD_INODE_FS_MAGIC 0x11307854
40 static DEFINE_MUTEX(mtd_mutex);
41 static struct vfsmount *mtd_inode_mnt __read_mostly;
44 * Data structure to hold the pointer to the mtd device as well
45 * as mode information ofr various use cases.
47 struct mtd_file_info {
50 enum mtd_file_modes mode;
53 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
55 struct mtd_file_info *mfi = file->private_data;
56 struct mtd_info *mtd = mfi->mtd;
62 offset += file->f_pos;
71 if (offset >= 0 && offset <= mtd->size)
72 return file->f_pos = offset;
79 static int mtd_open(struct inode *inode, struct file *file)
81 int minor = iminor(inode);
82 int devnum = minor >> 1;
85 struct mtd_file_info *mfi;
86 struct inode *mtd_ino;
88 DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
90 /* You can't open the RO devices RW */
91 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
94 mutex_lock(&mtd_mutex);
95 mtd = get_mtd_device(NULL, devnum);
102 if (mtd->type == MTD_ABSENT) {
108 mtd_ino = iget_locked(mtd_inode_mnt->mnt_sb, devnum);
114 if (mtd_ino->i_state & I_NEW) {
115 mtd_ino->i_private = mtd;
116 mtd_ino->i_mode = S_IFCHR;
117 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
118 unlock_new_inode(mtd_ino);
120 file->f_mapping = mtd_ino->i_mapping;
122 /* You can't open it RW if it's not a writeable device */
123 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
130 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
139 file->private_data = mfi;
142 mutex_unlock(&mtd_mutex);
146 /*====================================================================*/
148 static int mtd_close(struct inode *inode, struct file *file)
150 struct mtd_file_info *mfi = file->private_data;
151 struct mtd_info *mtd = mfi->mtd;
153 DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
155 /* Only sync if opened RW */
156 if ((file->f_mode & FMODE_WRITE) && mtd->sync)
162 file->private_data = NULL;
168 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
169 userspace buffer down and use it directly with readv/writev.
171 #define MAX_KMALLOC_SIZE 0x20000
173 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
175 struct mtd_file_info *mfi = file->private_data;
176 struct mtd_info *mtd = mfi->mtd;
178 size_t total_retlen=0;
183 DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
185 if (*ppos + count > mtd->size)
186 count = mtd->size - *ppos;
191 /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
192 and pass them directly to the MTD functions */
194 if (count > MAX_KMALLOC_SIZE)
195 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
197 kbuf=kmalloc(count, GFP_KERNEL);
204 if (count > MAX_KMALLOC_SIZE)
205 len = MAX_KMALLOC_SIZE;
210 case MTD_MODE_OTP_FACTORY:
211 ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
213 case MTD_MODE_OTP_USER:
214 ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
218 struct mtd_oob_ops ops;
220 ops.mode = MTD_OOB_RAW;
225 ret = mtd->read_oob(mtd, *ppos, &ops);
230 ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
232 /* Nand returns -EBADMSG on ecc errors, but it returns
233 * the data. For our userspace tools it is important
234 * to dump areas with ecc errors !
235 * For kernel internal usage it also might return -EUCLEAN
236 * to signal the caller that a bitflip has occured and has
237 * been corrected by the ECC algorithm.
238 * Userspace software which accesses NAND this way
239 * must be aware of the fact that it deals with NAND
241 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
243 if (copy_to_user(buf, kbuf, retlen)) {
248 total_retlen += retlen;
266 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
268 struct mtd_file_info *mfi = file->private_data;
269 struct mtd_info *mtd = mfi->mtd;
272 size_t total_retlen=0;
276 DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
278 if (*ppos == mtd->size)
281 if (*ppos + count > mtd->size)
282 count = mtd->size - *ppos;
287 if (count > MAX_KMALLOC_SIZE)
288 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
290 kbuf=kmalloc(count, GFP_KERNEL);
297 if (count > MAX_KMALLOC_SIZE)
298 len = MAX_KMALLOC_SIZE;
302 if (copy_from_user(kbuf, buf, len)) {
308 case MTD_MODE_OTP_FACTORY:
311 case MTD_MODE_OTP_USER:
312 if (!mtd->write_user_prot_reg) {
316 ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
321 struct mtd_oob_ops ops;
323 ops.mode = MTD_OOB_RAW;
328 ret = mtd->write_oob(mtd, *ppos, &ops);
334 ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
338 total_retlen += retlen;
352 /*======================================================================
354 IOCTL calls for getting device parameters.
356 ======================================================================*/
357 static void mtdchar_erase_callback (struct erase_info *instr)
359 wake_up((wait_queue_head_t *)instr->priv);
362 #ifdef CONFIG_HAVE_MTD_OTP
363 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
365 struct mtd_info *mtd = mfi->mtd;
369 case MTD_OTP_FACTORY:
370 if (!mtd->read_fact_prot_reg)
373 mfi->mode = MTD_MODE_OTP_FACTORY;
376 if (!mtd->read_fact_prot_reg)
379 mfi->mode = MTD_MODE_OTP_USER;
389 # define otp_select_filemode(f,m) -EOPNOTSUPP
392 static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
393 uint64_t start, uint32_t length, void __user *ptr,
394 uint32_t __user *retp)
396 struct mtd_oob_ops ops;
400 if (!(file->f_mode & FMODE_WRITE))
409 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
415 ops.ooboffs = start & (mtd->oobsize - 1);
417 ops.mode = MTD_OOB_PLACE;
419 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
422 ops.oobbuf = memdup_user(ptr, length);
423 if (IS_ERR(ops.oobbuf))
424 return PTR_ERR(ops.oobbuf);
426 start &= ~((uint64_t)mtd->oobsize - 1);
427 ret = mtd->write_oob(mtd, start, &ops);
429 if (ops.oobretlen > 0xFFFFFFFFU)
431 retlen = ops.oobretlen;
432 if (copy_to_user(retp, &retlen, sizeof(length)))
439 static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
440 uint32_t length, void __user *ptr, uint32_t __user *retp)
442 struct mtd_oob_ops ops;
451 ret = access_ok(VERIFY_WRITE, ptr,
452 length) ? 0 : -EFAULT;
457 ops.ooboffs = start & (mtd->oobsize - 1);
459 ops.mode = MTD_OOB_PLACE;
461 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
464 ops.oobbuf = kmalloc(length, GFP_KERNEL);
468 start &= ~((uint64_t)mtd->oobsize - 1);
469 ret = mtd->read_oob(mtd, start, &ops);
471 if (put_user(ops.oobretlen, retp))
473 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
481 static int mtd_ioctl(struct file *file, u_int cmd, u_long arg)
483 struct mtd_file_info *mfi = file->private_data;
484 struct mtd_info *mtd = mfi->mtd;
485 void __user *argp = (void __user *)arg;
488 struct mtd_info_user info;
490 DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
492 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
494 if (!access_ok(VERIFY_READ, argp, size))
498 if (!access_ok(VERIFY_WRITE, argp, size))
503 case MEMGETREGIONCOUNT:
504 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
508 case MEMGETREGIONINFO:
511 struct mtd_erase_region_info *kr;
512 struct region_info_user __user *ur = argp;
514 if (get_user(ur_idx, &(ur->regionindex)))
517 kr = &(mtd->eraseregions[ur_idx]);
519 if (put_user(kr->offset, &(ur->offset))
520 || put_user(kr->erasesize, &(ur->erasesize))
521 || put_user(kr->numblocks, &(ur->numblocks)))
528 info.type = mtd->type;
529 info.flags = mtd->flags;
530 info.size = mtd->size;
531 info.erasesize = mtd->erasesize;
532 info.writesize = mtd->writesize;
533 info.oobsize = mtd->oobsize;
534 /* The below fields are obsolete */
537 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
544 struct erase_info *erase;
546 if(!(file->f_mode & FMODE_WRITE))
549 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
553 wait_queue_head_t waitq;
554 DECLARE_WAITQUEUE(wait, current);
556 init_waitqueue_head(&waitq);
558 if (cmd == MEMERASE64) {
559 struct erase_info_user64 einfo64;
561 if (copy_from_user(&einfo64, argp,
562 sizeof(struct erase_info_user64))) {
566 erase->addr = einfo64.start;
567 erase->len = einfo64.length;
569 struct erase_info_user einfo32;
571 if (copy_from_user(&einfo32, argp,
572 sizeof(struct erase_info_user))) {
576 erase->addr = einfo32.start;
577 erase->len = einfo32.length;
580 erase->callback = mtdchar_erase_callback;
581 erase->priv = (unsigned long)&waitq;
584 FIXME: Allow INTERRUPTIBLE. Which means
585 not having the wait_queue head on the stack.
587 If the wq_head is on the stack, and we
588 leave because we got interrupted, then the
589 wq_head is no longer there when the
590 callback routine tries to wake us up.
592 ret = mtd->erase(mtd, erase);
594 set_current_state(TASK_UNINTERRUPTIBLE);
595 add_wait_queue(&waitq, &wait);
596 if (erase->state != MTD_ERASE_DONE &&
597 erase->state != MTD_ERASE_FAILED)
599 remove_wait_queue(&waitq, &wait);
600 set_current_state(TASK_RUNNING);
602 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
611 struct mtd_oob_buf buf;
612 struct mtd_oob_buf __user *buf_user = argp;
614 /* NOTE: writes return length to buf_user->length */
615 if (copy_from_user(&buf, argp, sizeof(buf)))
618 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
619 buf.ptr, &buf_user->length);
625 struct mtd_oob_buf buf;
626 struct mtd_oob_buf __user *buf_user = argp;
628 /* NOTE: writes return length to buf_user->start */
629 if (copy_from_user(&buf, argp, sizeof(buf)))
632 ret = mtd_do_readoob(mtd, buf.start, buf.length,
633 buf.ptr, &buf_user->start);
639 struct mtd_oob_buf64 buf;
640 struct mtd_oob_buf64 __user *buf_user = argp;
642 if (copy_from_user(&buf, argp, sizeof(buf)))
645 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
646 (void __user *)(uintptr_t)buf.usr_ptr,
653 struct mtd_oob_buf64 buf;
654 struct mtd_oob_buf64 __user *buf_user = argp;
656 if (copy_from_user(&buf, argp, sizeof(buf)))
659 ret = mtd_do_readoob(mtd, buf.start, buf.length,
660 (void __user *)(uintptr_t)buf.usr_ptr,
667 struct erase_info_user einfo;
669 if (copy_from_user(&einfo, argp, sizeof(einfo)))
675 ret = mtd->lock(mtd, einfo.start, einfo.length);
681 struct erase_info_user einfo;
683 if (copy_from_user(&einfo, argp, sizeof(einfo)))
689 ret = mtd->unlock(mtd, einfo.start, einfo.length);
695 struct erase_info_user einfo;
697 if (copy_from_user(&einfo, argp, sizeof(einfo)))
703 ret = mtd->is_locked(mtd, einfo.start, einfo.length);
707 /* Legacy interface */
710 struct nand_oobinfo oi;
714 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
717 oi.useecc = MTD_NANDECC_AUTOPLACE;
718 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
719 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
721 oi.eccbytes = mtd->ecclayout->eccbytes;
723 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
732 if (copy_from_user(&offs, argp, sizeof(loff_t)))
734 if (!mtd->block_isbad)
737 return mtd->block_isbad(mtd, offs);
745 if (copy_from_user(&offs, argp, sizeof(loff_t)))
747 if (!mtd->block_markbad)
750 return mtd->block_markbad(mtd, offs);
754 #ifdef CONFIG_HAVE_MTD_OTP
758 if (copy_from_user(&mode, argp, sizeof(int)))
761 mfi->mode = MTD_MODE_NORMAL;
763 ret = otp_select_filemode(mfi, mode);
769 case OTPGETREGIONCOUNT:
770 case OTPGETREGIONINFO:
772 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
777 case MTD_MODE_OTP_FACTORY:
778 if (mtd->get_fact_prot_info)
779 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
781 case MTD_MODE_OTP_USER:
782 if (mtd->get_user_prot_info)
783 ret = mtd->get_user_prot_info(mtd, buf, 4096);
789 if (cmd == OTPGETREGIONCOUNT) {
790 int nbr = ret / sizeof(struct otp_info);
791 ret = copy_to_user(argp, &nbr, sizeof(int));
793 ret = copy_to_user(argp, buf, ret);
803 struct otp_info oinfo;
805 if (mfi->mode != MTD_MODE_OTP_USER)
807 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
809 if (!mtd->lock_user_prot_reg)
811 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
821 if (copy_to_user(argp, mtd->ecclayout,
822 sizeof(struct nand_ecclayout)))
829 if (copy_to_user(argp, &mtd->ecc_stats,
830 sizeof(struct mtd_ecc_stats)))
840 case MTD_MODE_OTP_FACTORY:
841 case MTD_MODE_OTP_USER:
842 ret = otp_select_filemode(mfi, arg);
846 if (!mtd->read_oob || !mtd->write_oob)
850 case MTD_MODE_NORMAL:
866 static long mtd_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
870 mutex_lock(&mtd_mutex);
871 ret = mtd_ioctl(file, cmd, arg);
872 mutex_unlock(&mtd_mutex);
879 struct mtd_oob_buf32 {
882 compat_caddr_t ptr; /* unsigned char* */
885 #define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
886 #define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
888 static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
891 struct mtd_file_info *mfi = file->private_data;
892 struct mtd_info *mtd = mfi->mtd;
893 void __user *argp = compat_ptr(arg);
896 mutex_lock(&mtd_mutex);
901 struct mtd_oob_buf32 buf;
902 struct mtd_oob_buf32 __user *buf_user = argp;
904 if (copy_from_user(&buf, argp, sizeof(buf)))
907 ret = mtd_do_writeoob(file, mtd, buf.start,
908 buf.length, compat_ptr(buf.ptr),
915 struct mtd_oob_buf32 buf;
916 struct mtd_oob_buf32 __user *buf_user = argp;
918 /* NOTE: writes return length to buf->start */
919 if (copy_from_user(&buf, argp, sizeof(buf)))
922 ret = mtd_do_readoob(mtd, buf.start,
923 buf.length, compat_ptr(buf.ptr),
928 ret = mtd_ioctl(file, cmd, (unsigned long)argp);
931 mutex_unlock(&mtd_mutex);
936 #endif /* CONFIG_COMPAT */
939 * try to determine where a shared mapping can be made
940 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
944 static unsigned long mtd_get_unmapped_area(struct file *file,
950 struct mtd_file_info *mfi = file->private_data;
951 struct mtd_info *mtd = mfi->mtd;
953 if (mtd->get_unmapped_area) {
954 unsigned long offset;
957 return (unsigned long) -EINVAL;
959 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
960 return (unsigned long) -EINVAL;
962 offset = pgoff << PAGE_SHIFT;
963 if (offset > mtd->size - len)
964 return (unsigned long) -EINVAL;
966 return mtd->get_unmapped_area(mtd, len, offset, flags);
969 /* can't map directly */
970 return (unsigned long) -ENOSYS;
975 * set up a mapping for shared memory segments
977 static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
980 struct mtd_file_info *mfi = file->private_data;
981 struct mtd_info *mtd = mfi->mtd;
982 struct map_info *map = mtd->priv;
987 if (mtd->type == MTD_RAM || mtd->type == MTD_ROM) {
988 off = vma->vm_pgoff << PAGE_SHIFT;
990 len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
992 if ((vma->vm_end - vma->vm_start + off) > len)
996 vma->vm_pgoff = off >> PAGE_SHIFT;
997 vma->vm_flags |= VM_IO | VM_RESERVED;
999 #ifdef pgprot_noncached
1000 if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
1001 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1003 if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
1004 vma->vm_end - vma->vm_start,
1012 return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
1016 static const struct file_operations mtd_fops = {
1017 .owner = THIS_MODULE,
1018 .llseek = mtd_lseek,
1021 .unlocked_ioctl = mtd_unlocked_ioctl,
1022 #ifdef CONFIG_COMPAT
1023 .compat_ioctl = mtd_compat_ioctl,
1026 .release = mtd_close,
1029 .get_unmapped_area = mtd_get_unmapped_area,
1033 static int mtd_inodefs_get_sb(struct file_system_type *fs_type, int flags,
1034 const char *dev_name, void *data,
1035 struct vfsmount *mnt)
1037 return get_sb_pseudo(fs_type, "mtd_inode:", NULL, MTD_INODE_FS_MAGIC,
1041 static struct file_system_type mtd_inodefs_type = {
1042 .name = "mtd_inodefs",
1043 .get_sb = mtd_inodefs_get_sb,
1044 .kill_sb = kill_anon_super,
1047 static void mtdchar_notify_add(struct mtd_info *mtd)
1051 static void mtdchar_notify_remove(struct mtd_info *mtd)
1053 struct inode *mtd_ino = ilookup(mtd_inode_mnt->mnt_sb, mtd->index);
1056 /* Destroy the inode if it exists */
1057 mtd_ino->i_nlink = 0;
1062 static struct mtd_notifier mtdchar_notifier = {
1063 .add = mtdchar_notify_add,
1064 .remove = mtdchar_notify_remove,
1067 static int __init init_mtdchar(void)
1071 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1074 pr_notice("Can't allocate major number %d for "
1075 "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
1079 ret = register_filesystem(&mtd_inodefs_type);
1081 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
1082 goto err_unregister_chdev;
1085 mtd_inode_mnt = kern_mount(&mtd_inodefs_type);
1086 if (IS_ERR(mtd_inode_mnt)) {
1087 ret = PTR_ERR(mtd_inode_mnt);
1088 pr_notice("Error mounting mtd_inodefs filesystem: %d\n", ret);
1089 goto err_unregister_filesystem;
1091 register_mtd_user(&mtdchar_notifier);
1095 err_unregister_filesystem:
1096 unregister_filesystem(&mtd_inodefs_type);
1097 err_unregister_chdev:
1098 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1102 static void __exit cleanup_mtdchar(void)
1104 unregister_mtd_user(&mtdchar_notifier);
1105 mntput(mtd_inode_mnt);
1106 unregister_filesystem(&mtd_inodefs_type);
1107 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1110 module_init(init_mtdchar);
1111 module_exit(cleanup_mtdchar);
1113 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1115 MODULE_LICENSE("GPL");
1116 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1117 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1118 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);