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/magic.h>
35 #include <linux/major.h>
36 #include <linux/mtd/mtd.h>
37 #include <linux/mtd/partitions.h>
38 #include <linux/mtd/map.h>
40 #include <asm/uaccess.h>
44 static DEFINE_MUTEX(mtd_mutex);
47 * Data structure to hold the pointer to the mtd device as well
48 * as mode information of various use cases.
50 struct mtd_file_info {
52 enum mtd_file_modes mode;
55 static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
57 struct mtd_file_info *mfi = file->private_data;
58 return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
61 static int mtdchar_open(struct inode *inode, struct file *file)
63 int minor = iminor(inode);
64 int devnum = minor >> 1;
67 struct mtd_file_info *mfi;
69 pr_debug("MTD_open\n");
71 /* You can't open the RO devices RW */
72 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
75 mutex_lock(&mtd_mutex);
76 mtd = get_mtd_device(NULL, devnum);
83 if (mtd->type == MTD_ABSENT) {
88 /* You can't open it RW if it's not a writeable device */
89 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
94 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
100 file->private_data = mfi;
101 mutex_unlock(&mtd_mutex);
107 mutex_unlock(&mtd_mutex);
111 /*====================================================================*/
113 static int mtdchar_close(struct inode *inode, struct file *file)
115 struct mtd_file_info *mfi = file->private_data;
116 struct mtd_info *mtd = mfi->mtd;
118 pr_debug("MTD_close\n");
120 /* Only sync if opened RW */
121 if ((file->f_mode & FMODE_WRITE))
125 file->private_data = NULL;
129 } /* mtdchar_close */
131 /* Back in June 2001, dwmw2 wrote:
133 * FIXME: This _really_ needs to die. In 2.5, we should lock the
134 * userspace buffer down and use it directly with readv/writev.
136 * The implementation below, using mtd_kmalloc_up_to, mitigates
137 * allocation failures when the system is under low-memory situations
138 * or if memory is highly fragmented at the cost of reducing the
139 * performance of the requested transfer due to a smaller buffer size.
141 * A more complex but more memory-efficient implementation based on
142 * get_user_pages and iovecs to cover extents of those pages is a
143 * longer-term goal, as intimated by dwmw2 above. However, for the
144 * write case, this requires yet more complex head and tail transfer
145 * handling when those head and tail offsets and sizes are such that
146 * alignment requirements are not met in the NAND subdriver.
149 static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
152 struct mtd_file_info *mfi = file->private_data;
153 struct mtd_info *mtd = mfi->mtd;
155 size_t total_retlen=0;
161 pr_debug("MTD_read\n");
163 if (*ppos + count > mtd->size) {
164 if (*ppos < mtd->size)
165 count = mtd->size - *ppos;
173 kbuf = mtd_kmalloc_up_to(mtd, &size);
178 len = min_t(size_t, count, size);
181 case MTD_FILE_MODE_OTP_FACTORY:
182 ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
185 case MTD_FILE_MODE_OTP_USER:
186 ret = mtd_read_user_prot_reg(mtd, *ppos, len,
189 case MTD_FILE_MODE_RAW:
191 struct mtd_oob_ops ops;
193 ops.mode = MTD_OPS_RAW;
198 ret = mtd_read_oob(mtd, *ppos, &ops);
203 ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
205 /* Nand returns -EBADMSG on ECC errors, but it returns
206 * the data. For our userspace tools it is important
207 * to dump areas with ECC errors!
208 * For kernel internal usage it also might return -EUCLEAN
209 * to signal the caller that a bitflip has occurred and has
210 * been corrected by the ECC algorithm.
211 * Userspace software which accesses NAND this way
212 * must be aware of the fact that it deals with NAND
214 if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
216 if (copy_to_user(buf, kbuf, retlen)) {
221 total_retlen += retlen;
239 static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
242 struct mtd_file_info *mfi = file->private_data;
243 struct mtd_info *mtd = mfi->mtd;
247 size_t total_retlen=0;
251 pr_debug("MTD_write\n");
253 if (*ppos >= mtd->size)
256 if (*ppos + count > mtd->size)
257 count = mtd->size - *ppos;
262 kbuf = mtd_kmalloc_up_to(mtd, &size);
267 len = min_t(size_t, count, size);
269 if (copy_from_user(kbuf, buf, len)) {
275 case MTD_FILE_MODE_OTP_FACTORY:
278 case MTD_FILE_MODE_OTP_USER:
279 ret = mtd_write_user_prot_reg(mtd, *ppos, len,
283 case MTD_FILE_MODE_RAW:
285 struct mtd_oob_ops ops;
287 ops.mode = MTD_OPS_RAW;
293 ret = mtd_write_oob(mtd, *ppos, &ops);
299 ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
303 * Return -ENOSPC only if no data could be written at all.
304 * Otherwise just return the number of bytes that actually
307 if ((ret == -ENOSPC) && (total_retlen))
312 total_retlen += retlen;
324 } /* mtdchar_write */
326 /*======================================================================
328 IOCTL calls for getting device parameters.
330 ======================================================================*/
331 static void mtdchar_erase_callback (struct erase_info *instr)
333 wake_up((wait_queue_head_t *)instr->priv);
336 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
338 struct mtd_info *mtd = mfi->mtd;
342 case MTD_OTP_FACTORY:
343 if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
347 mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
350 if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
354 mfi->mode = MTD_FILE_MODE_OTP_USER;
357 mfi->mode = MTD_FILE_MODE_NORMAL;
366 static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
367 uint64_t start, uint32_t length, void __user *ptr,
368 uint32_t __user *retp)
370 struct mtd_file_info *mfi = file->private_data;
371 struct mtd_oob_ops ops;
378 if (!mtd->_write_oob)
381 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
387 ops.ooboffs = start & (mtd->writesize - 1);
389 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
392 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
395 ops.oobbuf = memdup_user(ptr, length);
396 if (IS_ERR(ops.oobbuf))
397 return PTR_ERR(ops.oobbuf);
399 start &= ~((uint64_t)mtd->writesize - 1);
400 ret = mtd_write_oob(mtd, start, &ops);
402 if (ops.oobretlen > 0xFFFFFFFFU)
404 retlen = ops.oobretlen;
405 if (copy_to_user(retp, &retlen, sizeof(length)))
412 static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
413 uint64_t start, uint32_t length, void __user *ptr,
414 uint32_t __user *retp)
416 struct mtd_file_info *mfi = file->private_data;
417 struct mtd_oob_ops ops;
423 if (!access_ok(VERIFY_WRITE, ptr, length))
427 ops.ooboffs = start & (mtd->writesize - 1);
429 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
432 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
435 ops.oobbuf = kmalloc(length, GFP_KERNEL);
439 start &= ~((uint64_t)mtd->writesize - 1);
440 ret = mtd_read_oob(mtd, start, &ops);
442 if (put_user(ops.oobretlen, retp))
444 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
451 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
452 * data. For our userspace tools it is important to dump areas
454 * For kernel internal usage it also might return -EUCLEAN
455 * to signal the caller that a bitflip has occured and has
456 * been corrected by the ECC algorithm.
458 * Note: currently the standard NAND function, nand_read_oob_std,
459 * does not calculate ECC for the OOB area, so do not rely on
460 * this behavior unless you have replaced it with your own.
462 if (mtd_is_bitflip_or_eccerr(ret))
469 * Copies (and truncates, if necessary) data from the larger struct,
470 * nand_ecclayout, to the smaller, deprecated layout struct,
471 * nand_ecclayout_user. This is necessary only to support the deprecated
472 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
473 * nand_ecclayout flexibly (i.e. the struct may change size in new
474 * releases without requiring major rewrites).
476 static int shrink_ecclayout(const struct nand_ecclayout *from,
477 struct nand_ecclayout_user *to)
484 memset(to, 0, sizeof(*to));
486 to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
487 for (i = 0; i < to->eccbytes; i++)
488 to->eccpos[i] = from->eccpos[i];
490 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
491 if (from->oobfree[i].length == 0 &&
492 from->oobfree[i].offset == 0)
494 to->oobavail += from->oobfree[i].length;
495 to->oobfree[i] = from->oobfree[i];
501 static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
502 struct blkpg_ioctl_arg *arg)
504 struct blkpg_partition p;
506 if (!capable(CAP_SYS_ADMIN))
509 if (copy_from_user(&p, arg->data, sizeof(p)))
513 case BLKPG_ADD_PARTITION:
515 /* Only master mtd device must be used to add partitions */
516 if (mtd_is_partition(mtd))
519 /* Sanitize user input */
520 p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
522 return mtd_add_partition(mtd, p.devname, p.start, p.length);
524 case BLKPG_DEL_PARTITION:
529 return mtd_del_partition(mtd, p.pno);
536 static int mtdchar_write_ioctl(struct mtd_info *mtd,
537 struct mtd_write_req __user *argp)
539 struct mtd_write_req req;
540 struct mtd_oob_ops ops;
541 const void __user *usr_data, *usr_oob;
544 if (copy_from_user(&req, argp, sizeof(req)))
547 usr_data = (const void __user *)(uintptr_t)req.usr_data;
548 usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
549 if (!access_ok(VERIFY_READ, usr_data, req.len) ||
550 !access_ok(VERIFY_READ, usr_oob, req.ooblen))
553 if (!mtd->_write_oob)
557 ops.len = (size_t)req.len;
558 ops.ooblen = (size_t)req.ooblen;
562 ops.datbuf = memdup_user(usr_data, ops.len);
563 if (IS_ERR(ops.datbuf))
564 return PTR_ERR(ops.datbuf);
570 ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
571 if (IS_ERR(ops.oobbuf)) {
573 return PTR_ERR(ops.oobbuf);
579 ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
587 static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
589 struct mtd_file_info *mfi = file->private_data;
590 struct mtd_info *mtd = mfi->mtd;
591 void __user *argp = (void __user *)arg;
594 struct mtd_info_user info;
596 pr_debug("MTD_ioctl\n");
598 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
600 if (!access_ok(VERIFY_READ, argp, size))
604 if (!access_ok(VERIFY_WRITE, argp, size))
609 * Check the file mode to require "dangerous" commands to have write
613 /* "safe" commands */
614 case MEMGETREGIONCOUNT:
615 case MEMGETREGIONINFO:
623 case OTPGETREGIONCOUNT:
624 case OTPGETREGIONINFO:
632 /* "dangerous" commands */
642 if (!(file->f_mode & FMODE_WRITE))
651 case MEMGETREGIONCOUNT:
652 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
656 case MEMGETREGIONINFO:
659 struct mtd_erase_region_info *kr;
660 struct region_info_user __user *ur = argp;
662 if (get_user(ur_idx, &(ur->regionindex)))
665 if (ur_idx >= mtd->numeraseregions)
668 kr = &(mtd->eraseregions[ur_idx]);
670 if (put_user(kr->offset, &(ur->offset))
671 || put_user(kr->erasesize, &(ur->erasesize))
672 || put_user(kr->numblocks, &(ur->numblocks)))
679 memset(&info, 0, sizeof(info));
680 info.type = mtd->type;
681 info.flags = mtd->flags;
682 info.size = mtd->size;
683 info.erasesize = mtd->erasesize;
684 info.writesize = mtd->writesize;
685 info.oobsize = mtd->oobsize;
686 /* The below field is obsolete */
688 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
695 struct erase_info *erase;
697 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
701 wait_queue_head_t waitq;
702 DECLARE_WAITQUEUE(wait, current);
704 init_waitqueue_head(&waitq);
706 if (cmd == MEMERASE64) {
707 struct erase_info_user64 einfo64;
709 if (copy_from_user(&einfo64, argp,
710 sizeof(struct erase_info_user64))) {
714 erase->addr = einfo64.start;
715 erase->len = einfo64.length;
717 struct erase_info_user einfo32;
719 if (copy_from_user(&einfo32, argp,
720 sizeof(struct erase_info_user))) {
724 erase->addr = einfo32.start;
725 erase->len = einfo32.length;
728 erase->callback = mtdchar_erase_callback;
729 erase->priv = (unsigned long)&waitq;
732 FIXME: Allow INTERRUPTIBLE. Which means
733 not having the wait_queue head on the stack.
735 If the wq_head is on the stack, and we
736 leave because we got interrupted, then the
737 wq_head is no longer there when the
738 callback routine tries to wake us up.
740 ret = mtd_erase(mtd, erase);
742 set_current_state(TASK_UNINTERRUPTIBLE);
743 add_wait_queue(&waitq, &wait);
744 if (erase->state != MTD_ERASE_DONE &&
745 erase->state != MTD_ERASE_FAILED)
747 remove_wait_queue(&waitq, &wait);
748 set_current_state(TASK_RUNNING);
750 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
759 struct mtd_oob_buf buf;
760 struct mtd_oob_buf __user *buf_user = argp;
762 /* NOTE: writes return length to buf_user->length */
763 if (copy_from_user(&buf, argp, sizeof(buf)))
766 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
767 buf.ptr, &buf_user->length);
773 struct mtd_oob_buf buf;
774 struct mtd_oob_buf __user *buf_user = argp;
776 /* NOTE: writes return length to buf_user->start */
777 if (copy_from_user(&buf, argp, sizeof(buf)))
780 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
781 buf.ptr, &buf_user->start);
787 struct mtd_oob_buf64 buf;
788 struct mtd_oob_buf64 __user *buf_user = argp;
790 if (copy_from_user(&buf, argp, sizeof(buf)))
793 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
794 (void __user *)(uintptr_t)buf.usr_ptr,
801 struct mtd_oob_buf64 buf;
802 struct mtd_oob_buf64 __user *buf_user = argp;
804 if (copy_from_user(&buf, argp, sizeof(buf)))
807 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
808 (void __user *)(uintptr_t)buf.usr_ptr,
815 ret = mtdchar_write_ioctl(mtd,
816 (struct mtd_write_req __user *)arg);
822 struct erase_info_user einfo;
824 if (copy_from_user(&einfo, argp, sizeof(einfo)))
827 ret = mtd_lock(mtd, einfo.start, einfo.length);
833 struct erase_info_user einfo;
835 if (copy_from_user(&einfo, argp, sizeof(einfo)))
838 ret = mtd_unlock(mtd, einfo.start, einfo.length);
844 struct erase_info_user einfo;
846 if (copy_from_user(&einfo, argp, sizeof(einfo)))
849 ret = mtd_is_locked(mtd, einfo.start, einfo.length);
853 /* Legacy interface */
856 struct nand_oobinfo oi;
860 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
863 oi.useecc = MTD_NANDECC_AUTOPLACE;
864 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
865 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
867 oi.eccbytes = mtd->ecclayout->eccbytes;
869 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
878 if (copy_from_user(&offs, argp, sizeof(loff_t)))
880 return mtd_block_isbad(mtd, offs);
888 if (copy_from_user(&offs, argp, sizeof(loff_t)))
890 return mtd_block_markbad(mtd, offs);
897 if (copy_from_user(&mode, argp, sizeof(int)))
900 mfi->mode = MTD_FILE_MODE_NORMAL;
902 ret = otp_select_filemode(mfi, mode);
908 case OTPGETREGIONCOUNT:
909 case OTPGETREGIONINFO:
911 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
916 case MTD_FILE_MODE_OTP_FACTORY:
917 ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
919 case MTD_FILE_MODE_OTP_USER:
920 ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
927 if (cmd == OTPGETREGIONCOUNT) {
928 int nbr = retlen / sizeof(struct otp_info);
929 ret = copy_to_user(argp, &nbr, sizeof(int));
931 ret = copy_to_user(argp, buf, retlen);
941 struct otp_info oinfo;
943 if (mfi->mode != MTD_FILE_MODE_OTP_USER)
945 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
947 ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
951 /* This ioctl is being deprecated - it truncates the ECC layout */
954 struct nand_ecclayout_user *usrlay;
959 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
963 shrink_ecclayout(mtd->ecclayout, usrlay);
965 if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
973 if (copy_to_user(argp, &mtd->ecc_stats,
974 sizeof(struct mtd_ecc_stats)))
984 case MTD_FILE_MODE_OTP_FACTORY:
985 case MTD_FILE_MODE_OTP_USER:
986 ret = otp_select_filemode(mfi, arg);
989 case MTD_FILE_MODE_RAW:
990 if (!mtd_has_oob(mtd))
994 case MTD_FILE_MODE_NORMAL:
1005 struct blkpg_ioctl_arg __user *blk_arg = argp;
1006 struct blkpg_ioctl_arg a;
1008 if (copy_from_user(&a, blk_arg, sizeof(a)))
1011 ret = mtdchar_blkpg_ioctl(mtd, &a);
1017 /* No reread partition feature. Just return ok */
1024 } /* memory_ioctl */
1026 static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1030 mutex_lock(&mtd_mutex);
1031 ret = mtdchar_ioctl(file, cmd, arg);
1032 mutex_unlock(&mtd_mutex);
1037 #ifdef CONFIG_COMPAT
1039 struct mtd_oob_buf32 {
1042 compat_caddr_t ptr; /* unsigned char* */
1045 #define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1046 #define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1048 static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1051 struct mtd_file_info *mfi = file->private_data;
1052 struct mtd_info *mtd = mfi->mtd;
1053 void __user *argp = compat_ptr(arg);
1056 mutex_lock(&mtd_mutex);
1061 struct mtd_oob_buf32 buf;
1062 struct mtd_oob_buf32 __user *buf_user = argp;
1064 if (!(file->f_mode & FMODE_WRITE)) {
1069 if (copy_from_user(&buf, argp, sizeof(buf)))
1072 ret = mtdchar_writeoob(file, mtd, buf.start,
1073 buf.length, compat_ptr(buf.ptr),
1080 struct mtd_oob_buf32 buf;
1081 struct mtd_oob_buf32 __user *buf_user = argp;
1083 /* NOTE: writes return length to buf->start */
1084 if (copy_from_user(&buf, argp, sizeof(buf)))
1087 ret = mtdchar_readoob(file, mtd, buf.start,
1088 buf.length, compat_ptr(buf.ptr),
1095 /* Convert from blkpg_compat_ioctl_arg to blkpg_ioctl_arg */
1096 struct blkpg_compat_ioctl_arg __user *uarg = argp;
1097 struct blkpg_compat_ioctl_arg compat_arg;
1098 struct blkpg_ioctl_arg a;
1100 if (copy_from_user(&compat_arg, uarg, sizeof(compat_arg))) {
1105 memset(&a, 0, sizeof(a));
1106 a.op = compat_arg.op;
1107 a.flags = compat_arg.flags;
1108 a.datalen = compat_arg.datalen;
1109 a.data = compat_ptr(compat_arg.data);
1111 ret = mtdchar_blkpg_ioctl(mtd, &a);
1116 ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1119 mutex_unlock(&mtd_mutex);
1124 #endif /* CONFIG_COMPAT */
1127 * try to determine where a shared mapping can be made
1128 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1132 static unsigned long mtdchar_get_unmapped_area(struct file *file,
1135 unsigned long pgoff,
1136 unsigned long flags)
1138 struct mtd_file_info *mfi = file->private_data;
1139 struct mtd_info *mtd = mfi->mtd;
1140 unsigned long offset;
1144 return (unsigned long) -EINVAL;
1146 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1147 return (unsigned long) -EINVAL;
1149 offset = pgoff << PAGE_SHIFT;
1150 if (offset > mtd->size - len)
1151 return (unsigned long) -EINVAL;
1153 ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1154 return ret == -EOPNOTSUPP ? -ENODEV : ret;
1157 static unsigned mtdchar_mmap_capabilities(struct file *file)
1159 struct mtd_file_info *mfi = file->private_data;
1161 return mtd_mmap_capabilities(mfi->mtd);
1166 * set up a mapping for shared memory segments
1168 static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1171 struct mtd_file_info *mfi = file->private_data;
1172 struct mtd_info *mtd = mfi->mtd;
1173 struct map_info *map = mtd->priv;
1175 /* This is broken because it assumes the MTD device is map-based
1176 and that mtd->priv is a valid struct map_info. It should be
1177 replaced with something that uses the mtd_get_unmapped_area()
1178 operation properly. */
1179 if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1180 #ifdef pgprot_noncached
1181 if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1182 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1184 return vm_iomap_memory(vma, map->phys, map->size);
1188 return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1192 static const struct file_operations mtd_fops = {
1193 .owner = THIS_MODULE,
1194 .llseek = mtdchar_lseek,
1195 .read = mtdchar_read,
1196 .write = mtdchar_write,
1197 .unlocked_ioctl = mtdchar_unlocked_ioctl,
1198 #ifdef CONFIG_COMPAT
1199 .compat_ioctl = mtdchar_compat_ioctl,
1201 .open = mtdchar_open,
1202 .release = mtdchar_close,
1203 .mmap = mtdchar_mmap,
1205 .get_unmapped_area = mtdchar_get_unmapped_area,
1206 .mmap_capabilities = mtdchar_mmap_capabilities,
1210 int __init init_mtdchar(void)
1214 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1217 pr_err("Can't allocate major number %d for MTD\n",
1225 void __exit cleanup_mtdchar(void)
1227 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1230 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);