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>
33 #include <linux/blkpg.h>
34 #include <linux/mtd/mtd.h>
35 #include <linux/mtd/partitions.h>
36 #include <linux/mtd/map.h>
38 #include <asm/uaccess.h>
40 #define MTD_INODE_FS_MAGIC 0x11307854
41 static DEFINE_MUTEX(mtd_mutex);
42 static struct vfsmount *mtd_inode_mnt __read_mostly;
45 * Data structure to hold the pointer to the mtd device as well
46 * as mode information of various use cases.
48 struct mtd_file_info {
51 enum mtd_file_modes mode;
54 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
56 struct mtd_file_info *mfi = file->private_data;
57 struct mtd_info *mtd = mfi->mtd;
63 offset += file->f_pos;
72 if (offset >= 0 && offset <= mtd->size)
73 return file->f_pos = offset;
80 static int mtd_open(struct inode *inode, struct file *file)
82 int minor = iminor(inode);
83 int devnum = minor >> 1;
86 struct mtd_file_info *mfi;
87 struct inode *mtd_ino;
89 pr_debug("MTD_open\n");
91 /* You can't open the RO devices RW */
92 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
95 mutex_lock(&mtd_mutex);
96 mtd = get_mtd_device(NULL, devnum);
103 if (mtd->type == MTD_ABSENT) {
109 mtd_ino = iget_locked(mtd_inode_mnt->mnt_sb, devnum);
115 if (mtd_ino->i_state & I_NEW) {
116 mtd_ino->i_private = mtd;
117 mtd_ino->i_mode = S_IFCHR;
118 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
119 unlock_new_inode(mtd_ino);
121 file->f_mapping = mtd_ino->i_mapping;
123 /* You can't open it RW if it's not a writeable device */
124 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
131 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
140 file->private_data = mfi;
143 mutex_unlock(&mtd_mutex);
147 /*====================================================================*/
149 static int mtd_close(struct inode *inode, struct file *file)
151 struct mtd_file_info *mfi = file->private_data;
152 struct mtd_info *mtd = mfi->mtd;
154 pr_debug("MTD_close\n");
156 /* Only sync if opened RW */
157 if ((file->f_mode & FMODE_WRITE) && mtd->sync)
163 file->private_data = NULL;
169 /* Back in June 2001, dwmw2 wrote:
171 * FIXME: This _really_ needs to die. In 2.5, we should lock the
172 * userspace buffer down and use it directly with readv/writev.
174 * The implementation below, using mtd_kmalloc_up_to, mitigates
175 * allocation failures when the system is under low-memory situations
176 * or if memory is highly fragmented at the cost of reducing the
177 * performance of the requested transfer due to a smaller buffer size.
179 * A more complex but more memory-efficient implementation based on
180 * get_user_pages and iovecs to cover extents of those pages is a
181 * longer-term goal, as intimated by dwmw2 above. However, for the
182 * write case, this requires yet more complex head and tail transfer
183 * handling when those head and tail offsets and sizes are such that
184 * alignment requirements are not met in the NAND subdriver.
187 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
189 struct mtd_file_info *mfi = file->private_data;
190 struct mtd_info *mtd = mfi->mtd;
192 size_t total_retlen=0;
198 pr_debug("MTD_read\n");
200 if (*ppos + count > mtd->size)
201 count = mtd->size - *ppos;
206 kbuf = mtd_kmalloc_up_to(mtd, &size);
211 len = min_t(size_t, count, size);
214 case MTD_FILE_MODE_OTP_FACTORY:
215 ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
217 case MTD_FILE_MODE_OTP_USER:
218 ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
220 case MTD_FILE_MODE_RAW:
222 struct mtd_oob_ops ops;
224 ops.mode = MTD_OPS_RAW;
229 ret = mtd->read_oob(mtd, *ppos, &ops);
234 ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
236 /* Nand returns -EBADMSG on ECC errors, but it returns
237 * the data. For our userspace tools it is important
238 * to dump areas with ECC errors!
239 * For kernel internal usage it also might return -EUCLEAN
240 * to signal the caller that a bitflip has occurred and has
241 * been corrected by the ECC algorithm.
242 * Userspace software which accesses NAND this way
243 * must be aware of the fact that it deals with NAND
245 if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
247 if (copy_to_user(buf, kbuf, retlen)) {
252 total_retlen += retlen;
270 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
272 struct mtd_file_info *mfi = file->private_data;
273 struct mtd_info *mtd = mfi->mtd;
277 size_t total_retlen=0;
281 pr_debug("MTD_write\n");
283 if (*ppos == mtd->size)
286 if (*ppos + count > mtd->size)
287 count = mtd->size - *ppos;
292 kbuf = mtd_kmalloc_up_to(mtd, &size);
297 len = min_t(size_t, count, size);
299 if (copy_from_user(kbuf, buf, len)) {
305 case MTD_FILE_MODE_OTP_FACTORY:
308 case MTD_FILE_MODE_OTP_USER:
309 if (!mtd->write_user_prot_reg) {
313 ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
316 case MTD_FILE_MODE_RAW:
318 struct mtd_oob_ops ops;
320 ops.mode = MTD_OPS_RAW;
326 ret = mtd->write_oob(mtd, *ppos, &ops);
332 ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
336 total_retlen += retlen;
350 /*======================================================================
352 IOCTL calls for getting device parameters.
354 ======================================================================*/
355 static void mtdchar_erase_callback (struct erase_info *instr)
357 wake_up((wait_queue_head_t *)instr->priv);
360 #ifdef CONFIG_HAVE_MTD_OTP
361 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
363 struct mtd_info *mtd = mfi->mtd;
367 case MTD_OTP_FACTORY:
368 if (!mtd->read_fact_prot_reg)
371 mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
374 if (!mtd->read_fact_prot_reg)
377 mfi->mode = MTD_FILE_MODE_OTP_USER;
387 # define otp_select_filemode(f,m) -EOPNOTSUPP
390 static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
391 uint64_t start, uint32_t length, void __user *ptr,
392 uint32_t __user *retp)
394 struct mtd_file_info *mfi = file->private_data;
395 struct mtd_oob_ops ops;
399 if (!(file->f_mode & FMODE_WRITE))
408 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
414 ops.ooboffs = start & (mtd->writesize - 1);
416 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
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->writesize - 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 file *file, struct mtd_info *mtd,
440 uint64_t start, uint32_t length, void __user *ptr,
441 uint32_t __user *retp)
443 struct mtd_file_info *mfi = file->private_data;
444 struct mtd_oob_ops ops;
453 ret = access_ok(VERIFY_WRITE, ptr,
454 length) ? 0 : -EFAULT;
459 ops.ooboffs = start & (mtd->writesize - 1);
461 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
464 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
467 ops.oobbuf = kmalloc(length, GFP_KERNEL);
471 start &= ~((uint64_t)mtd->writesize - 1);
472 ret = mtd->read_oob(mtd, start, &ops);
474 if (put_user(ops.oobretlen, retp))
476 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
483 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
484 * data. For our userspace tools it is important to dump areas
486 * For kernel internal usage it also might return -EUCLEAN
487 * to signal the caller that a bitflip has occured and has
488 * been corrected by the ECC algorithm.
490 * Note: currently the standard NAND function, nand_read_oob_std,
491 * does not calculate ECC for the OOB area, so do not rely on
492 * this behavior unless you have replaced it with your own.
494 if (mtd_is_bitflip_or_eccerr(ret))
501 * Copies (and truncates, if necessary) data from the larger struct,
502 * nand_ecclayout, to the smaller, deprecated layout struct,
503 * nand_ecclayout_user. This is necessary only to support the deprecated
504 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
505 * nand_ecclayout flexibly (i.e. the struct may change size in new
506 * releases without requiring major rewrites).
508 static int shrink_ecclayout(const struct nand_ecclayout *from,
509 struct nand_ecclayout_user *to)
516 memset(to, 0, sizeof(*to));
518 to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
519 for (i = 0; i < to->eccbytes; i++)
520 to->eccpos[i] = from->eccpos[i];
522 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
523 if (from->oobfree[i].length == 0 &&
524 from->oobfree[i].offset == 0)
526 to->oobavail += from->oobfree[i].length;
527 to->oobfree[i] = from->oobfree[i];
533 static int mtd_blkpg_ioctl(struct mtd_info *mtd,
534 struct blkpg_ioctl_arg __user *arg)
536 struct blkpg_ioctl_arg a;
537 struct blkpg_partition p;
539 if (!capable(CAP_SYS_ADMIN))
542 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
545 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
549 case BLKPG_ADD_PARTITION:
551 /* Only master mtd device must be used to add partitions */
552 if (mtd_is_partition(mtd))
555 return mtd_add_partition(mtd, p.devname, p.start, p.length);
557 case BLKPG_DEL_PARTITION:
562 return mtd_del_partition(mtd, p.pno);
569 static int mtd_write_ioctl(struct mtd_info *mtd,
570 struct mtd_write_req __user *argp)
572 struct mtd_write_req req;
573 struct mtd_oob_ops ops;
574 void __user *usr_data, *usr_oob;
577 if (copy_from_user(&req, argp, sizeof(req)) ||
578 !access_ok(VERIFY_READ, req.usr_data, req.len) ||
579 !access_ok(VERIFY_READ, req.usr_oob, req.ooblen))
585 ops.len = (size_t)req.len;
586 ops.ooblen = (size_t)req.ooblen;
589 usr_data = (void __user *)(uintptr_t)req.usr_data;
590 usr_oob = (void __user *)(uintptr_t)req.usr_oob;
593 ops.datbuf = memdup_user(usr_data, ops.len);
594 if (IS_ERR(ops.datbuf))
595 return PTR_ERR(ops.datbuf);
601 ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
602 if (IS_ERR(ops.oobbuf)) {
604 return PTR_ERR(ops.oobbuf);
610 ret = mtd->write_oob(mtd, (loff_t)req.start, &ops);
618 static int mtd_ioctl(struct file *file, u_int cmd, u_long arg)
620 struct mtd_file_info *mfi = file->private_data;
621 struct mtd_info *mtd = mfi->mtd;
622 void __user *argp = (void __user *)arg;
625 struct mtd_info_user info;
627 pr_debug("MTD_ioctl\n");
629 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
631 if (!access_ok(VERIFY_READ, argp, size))
635 if (!access_ok(VERIFY_WRITE, argp, size))
640 case MEMGETREGIONCOUNT:
641 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
645 case MEMGETREGIONINFO:
648 struct mtd_erase_region_info *kr;
649 struct region_info_user __user *ur = argp;
651 if (get_user(ur_idx, &(ur->regionindex)))
654 if (ur_idx >= mtd->numeraseregions)
657 kr = &(mtd->eraseregions[ur_idx]);
659 if (put_user(kr->offset, &(ur->offset))
660 || put_user(kr->erasesize, &(ur->erasesize))
661 || put_user(kr->numblocks, &(ur->numblocks)))
668 memset(&info, 0, sizeof(info));
669 info.type = mtd->type;
670 info.flags = mtd->flags;
671 info.size = mtd->size;
672 info.erasesize = mtd->erasesize;
673 info.writesize = mtd->writesize;
674 info.oobsize = mtd->oobsize;
675 /* The below field is obsolete */
677 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
684 struct erase_info *erase;
686 if(!(file->f_mode & FMODE_WRITE))
689 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
693 wait_queue_head_t waitq;
694 DECLARE_WAITQUEUE(wait, current);
696 init_waitqueue_head(&waitq);
698 if (cmd == MEMERASE64) {
699 struct erase_info_user64 einfo64;
701 if (copy_from_user(&einfo64, argp,
702 sizeof(struct erase_info_user64))) {
706 erase->addr = einfo64.start;
707 erase->len = einfo64.length;
709 struct erase_info_user einfo32;
711 if (copy_from_user(&einfo32, argp,
712 sizeof(struct erase_info_user))) {
716 erase->addr = einfo32.start;
717 erase->len = einfo32.length;
720 erase->callback = mtdchar_erase_callback;
721 erase->priv = (unsigned long)&waitq;
724 FIXME: Allow INTERRUPTIBLE. Which means
725 not having the wait_queue head on the stack.
727 If the wq_head is on the stack, and we
728 leave because we got interrupted, then the
729 wq_head is no longer there when the
730 callback routine tries to wake us up.
732 ret = mtd->erase(mtd, erase);
734 set_current_state(TASK_UNINTERRUPTIBLE);
735 add_wait_queue(&waitq, &wait);
736 if (erase->state != MTD_ERASE_DONE &&
737 erase->state != MTD_ERASE_FAILED)
739 remove_wait_queue(&waitq, &wait);
740 set_current_state(TASK_RUNNING);
742 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
751 struct mtd_oob_buf buf;
752 struct mtd_oob_buf __user *buf_user = argp;
754 /* NOTE: writes return length to buf_user->length */
755 if (copy_from_user(&buf, argp, sizeof(buf)))
758 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
759 buf.ptr, &buf_user->length);
765 struct mtd_oob_buf buf;
766 struct mtd_oob_buf __user *buf_user = argp;
768 /* NOTE: writes return length to buf_user->start */
769 if (copy_from_user(&buf, argp, sizeof(buf)))
772 ret = mtd_do_readoob(file, mtd, buf.start, buf.length,
773 buf.ptr, &buf_user->start);
779 struct mtd_oob_buf64 buf;
780 struct mtd_oob_buf64 __user *buf_user = argp;
782 if (copy_from_user(&buf, argp, sizeof(buf)))
785 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
786 (void __user *)(uintptr_t)buf.usr_ptr,
793 struct mtd_oob_buf64 buf;
794 struct mtd_oob_buf64 __user *buf_user = argp;
796 if (copy_from_user(&buf, argp, sizeof(buf)))
799 ret = mtd_do_readoob(file, mtd, buf.start, buf.length,
800 (void __user *)(uintptr_t)buf.usr_ptr,
807 ret = mtd_write_ioctl(mtd,
808 (struct mtd_write_req __user *)arg);
814 struct erase_info_user einfo;
816 if (copy_from_user(&einfo, argp, sizeof(einfo)))
822 ret = mtd->lock(mtd, einfo.start, einfo.length);
828 struct erase_info_user einfo;
830 if (copy_from_user(&einfo, argp, sizeof(einfo)))
836 ret = mtd->unlock(mtd, einfo.start, einfo.length);
842 struct erase_info_user einfo;
844 if (copy_from_user(&einfo, argp, sizeof(einfo)))
850 ret = mtd->is_locked(mtd, einfo.start, einfo.length);
854 /* Legacy interface */
857 struct nand_oobinfo oi;
861 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
864 oi.useecc = MTD_NANDECC_AUTOPLACE;
865 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
866 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
868 oi.eccbytes = mtd->ecclayout->eccbytes;
870 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
879 if (copy_from_user(&offs, argp, sizeof(loff_t)))
881 if (!mtd->block_isbad)
884 return mtd->block_isbad(mtd, offs);
892 if (copy_from_user(&offs, argp, sizeof(loff_t)))
894 if (!mtd->block_markbad)
897 return mtd->block_markbad(mtd, offs);
901 #ifdef CONFIG_HAVE_MTD_OTP
905 if (copy_from_user(&mode, argp, sizeof(int)))
908 mfi->mode = MTD_FILE_MODE_NORMAL;
910 ret = otp_select_filemode(mfi, mode);
916 case OTPGETREGIONCOUNT:
917 case OTPGETREGIONINFO:
919 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
924 case MTD_FILE_MODE_OTP_FACTORY:
925 if (mtd->get_fact_prot_info)
926 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
928 case MTD_FILE_MODE_OTP_USER:
929 if (mtd->get_user_prot_info)
930 ret = mtd->get_user_prot_info(mtd, buf, 4096);
936 if (cmd == OTPGETREGIONCOUNT) {
937 int nbr = ret / sizeof(struct otp_info);
938 ret = copy_to_user(argp, &nbr, sizeof(int));
940 ret = copy_to_user(argp, buf, ret);
950 struct otp_info oinfo;
952 if (mfi->mode != MTD_FILE_MODE_OTP_USER)
954 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
956 if (!mtd->lock_user_prot_reg)
958 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
963 /* This ioctl is being deprecated - it truncates the ECC layout */
966 struct nand_ecclayout_user *usrlay;
971 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
975 shrink_ecclayout(mtd->ecclayout, usrlay);
977 if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
985 if (copy_to_user(argp, &mtd->ecc_stats,
986 sizeof(struct mtd_ecc_stats)))
996 case MTD_FILE_MODE_OTP_FACTORY:
997 case MTD_FILE_MODE_OTP_USER:
998 ret = otp_select_filemode(mfi, arg);
1001 case MTD_FILE_MODE_RAW:
1002 if (!mtd->read_oob || !mtd->write_oob)
1006 case MTD_FILE_MODE_NORMAL:
1017 ret = mtd_blkpg_ioctl(mtd,
1018 (struct blkpg_ioctl_arg __user *)arg);
1024 /* No reread partition feature. Just return ok */
1034 } /* memory_ioctl */
1036 static long mtd_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1040 mutex_lock(&mtd_mutex);
1041 ret = mtd_ioctl(file, cmd, arg);
1042 mutex_unlock(&mtd_mutex);
1047 #ifdef CONFIG_COMPAT
1049 struct mtd_oob_buf32 {
1052 compat_caddr_t ptr; /* unsigned char* */
1055 #define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1056 #define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1058 static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
1061 struct mtd_file_info *mfi = file->private_data;
1062 struct mtd_info *mtd = mfi->mtd;
1063 void __user *argp = compat_ptr(arg);
1066 mutex_lock(&mtd_mutex);
1071 struct mtd_oob_buf32 buf;
1072 struct mtd_oob_buf32 __user *buf_user = argp;
1074 if (copy_from_user(&buf, argp, sizeof(buf)))
1077 ret = mtd_do_writeoob(file, mtd, buf.start,
1078 buf.length, compat_ptr(buf.ptr),
1085 struct mtd_oob_buf32 buf;
1086 struct mtd_oob_buf32 __user *buf_user = argp;
1088 /* NOTE: writes return length to buf->start */
1089 if (copy_from_user(&buf, argp, sizeof(buf)))
1092 ret = mtd_do_readoob(file, mtd, buf.start,
1093 buf.length, compat_ptr(buf.ptr),
1098 ret = mtd_ioctl(file, cmd, (unsigned long)argp);
1101 mutex_unlock(&mtd_mutex);
1106 #endif /* CONFIG_COMPAT */
1109 * try to determine where a shared mapping can be made
1110 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1114 static unsigned long mtd_get_unmapped_area(struct file *file,
1117 unsigned long pgoff,
1118 unsigned long flags)
1120 struct mtd_file_info *mfi = file->private_data;
1121 struct mtd_info *mtd = mfi->mtd;
1123 if (mtd->get_unmapped_area) {
1124 unsigned long offset;
1127 return (unsigned long) -EINVAL;
1129 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1130 return (unsigned long) -EINVAL;
1132 offset = pgoff << PAGE_SHIFT;
1133 if (offset > mtd->size - len)
1134 return (unsigned long) -EINVAL;
1136 return mtd->get_unmapped_area(mtd, len, offset, flags);
1139 /* can't map directly */
1140 return (unsigned long) -ENOSYS;
1145 * set up a mapping for shared memory segments
1147 static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
1150 struct mtd_file_info *mfi = file->private_data;
1151 struct mtd_info *mtd = mfi->mtd;
1152 struct map_info *map = mtd->priv;
1153 unsigned long start;
1157 if (mtd->type == MTD_RAM || mtd->type == MTD_ROM) {
1158 off = vma->vm_pgoff << PAGE_SHIFT;
1160 len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
1162 if ((vma->vm_end - vma->vm_start + off) > len)
1166 vma->vm_pgoff = off >> PAGE_SHIFT;
1167 vma->vm_flags |= VM_IO | VM_RESERVED;
1169 #ifdef pgprot_noncached
1170 if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
1171 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1173 if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
1174 vma->vm_end - vma->vm_start,
1182 return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
1186 static const struct file_operations mtd_fops = {
1187 .owner = THIS_MODULE,
1188 .llseek = mtd_lseek,
1191 .unlocked_ioctl = mtd_unlocked_ioctl,
1192 #ifdef CONFIG_COMPAT
1193 .compat_ioctl = mtd_compat_ioctl,
1196 .release = mtd_close,
1199 .get_unmapped_area = mtd_get_unmapped_area,
1203 static struct dentry *mtd_inodefs_mount(struct file_system_type *fs_type,
1204 int flags, const char *dev_name, void *data)
1206 return mount_pseudo(fs_type, "mtd_inode:", NULL, NULL, MTD_INODE_FS_MAGIC);
1209 static struct file_system_type mtd_inodefs_type = {
1210 .name = "mtd_inodefs",
1211 .mount = mtd_inodefs_mount,
1212 .kill_sb = kill_anon_super,
1215 static void mtdchar_notify_add(struct mtd_info *mtd)
1219 static void mtdchar_notify_remove(struct mtd_info *mtd)
1221 struct inode *mtd_ino = ilookup(mtd_inode_mnt->mnt_sb, mtd->index);
1224 /* Destroy the inode if it exists */
1225 clear_nlink(mtd_ino);
1230 static struct mtd_notifier mtdchar_notifier = {
1231 .add = mtdchar_notify_add,
1232 .remove = mtdchar_notify_remove,
1235 static int __init init_mtdchar(void)
1239 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1242 pr_notice("Can't allocate major number %d for "
1243 "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
1247 ret = register_filesystem(&mtd_inodefs_type);
1249 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
1250 goto err_unregister_chdev;
1253 mtd_inode_mnt = kern_mount(&mtd_inodefs_type);
1254 if (IS_ERR(mtd_inode_mnt)) {
1255 ret = PTR_ERR(mtd_inode_mnt);
1256 pr_notice("Error mounting mtd_inodefs filesystem: %d\n", ret);
1257 goto err_unregister_filesystem;
1259 register_mtd_user(&mtdchar_notifier);
1263 err_unregister_filesystem:
1264 unregister_filesystem(&mtd_inodefs_type);
1265 err_unregister_chdev:
1266 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1270 static void __exit cleanup_mtdchar(void)
1272 unregister_mtd_user(&mtdchar_notifier);
1273 kern_unmount(mtd_inode_mnt);
1274 unregister_filesystem(&mtd_inodefs_type);
1275 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1278 module_init(init_mtdchar);
1279 module_exit(cleanup_mtdchar);
1281 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1283 MODULE_LICENSE("GPL");
1284 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1285 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1286 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);