1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
6 #include <linux/device.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>
15 #include <linux/mutex.h>
16 #include <linux/backing-dev.h>
17 #include <linux/compat.h>
18 #include <linux/mount.h>
19 #include <linux/blkpg.h>
20 #include <linux/magic.h>
21 #include <linux/major.h>
22 #include <linux/mtd/mtd.h>
23 #include <linux/mtd/partitions.h>
24 #include <linux/mtd/map.h>
26 #include <linux/uaccess.h>
31 * Data structure to hold the pointer to the mtd device as well
32 * as mode information of various use cases.
34 struct mtd_file_info {
36 enum mtd_file_modes mode;
39 static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
41 struct mtd_file_info *mfi = file->private_data;
42 return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
45 static int mtdchar_open(struct inode *inode, struct file *file)
47 int minor = iminor(inode);
48 int devnum = minor >> 1;
51 struct mtd_file_info *mfi;
53 pr_debug("MTD_open\n");
55 /* You can't open the RO devices RW */
56 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
59 mtd = get_mtd_device(NULL, devnum);
64 if (mtd->type == MTD_ABSENT) {
69 /* You can't open it RW if it's not a writeable device */
70 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
75 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
81 file->private_data = mfi;
89 /*====================================================================*/
91 static int mtdchar_close(struct inode *inode, struct file *file)
93 struct mtd_file_info *mfi = file->private_data;
94 struct mtd_info *mtd = mfi->mtd;
96 pr_debug("MTD_close\n");
98 /* Only sync if opened RW */
99 if ((file->f_mode & FMODE_WRITE))
103 file->private_data = NULL;
107 } /* mtdchar_close */
109 /* Back in June 2001, dwmw2 wrote:
111 * FIXME: This _really_ needs to die. In 2.5, we should lock the
112 * userspace buffer down and use it directly with readv/writev.
114 * The implementation below, using mtd_kmalloc_up_to, mitigates
115 * allocation failures when the system is under low-memory situations
116 * or if memory is highly fragmented at the cost of reducing the
117 * performance of the requested transfer due to a smaller buffer size.
119 * A more complex but more memory-efficient implementation based on
120 * get_user_pages and iovecs to cover extents of those pages is a
121 * longer-term goal, as intimated by dwmw2 above. However, for the
122 * write case, this requires yet more complex head and tail transfer
123 * handling when those head and tail offsets and sizes are such that
124 * alignment requirements are not met in the NAND subdriver.
127 static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
130 struct mtd_file_info *mfi = file->private_data;
131 struct mtd_info *mtd = mfi->mtd;
133 size_t total_retlen=0;
139 pr_debug("MTD_read\n");
141 if (*ppos + count > mtd->size) {
142 if (*ppos < mtd->size)
143 count = mtd->size - *ppos;
151 kbuf = mtd_kmalloc_up_to(mtd, &size);
156 len = min_t(size_t, count, size);
159 case MTD_FILE_MODE_OTP_FACTORY:
160 ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
163 case MTD_FILE_MODE_OTP_USER:
164 ret = mtd_read_user_prot_reg(mtd, *ppos, len,
167 case MTD_FILE_MODE_RAW:
169 struct mtd_oob_ops ops = {};
171 ops.mode = MTD_OPS_RAW;
176 ret = mtd_read_oob(mtd, *ppos, &ops);
181 ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
183 /* Nand returns -EBADMSG on ECC errors, but it returns
184 * the data. For our userspace tools it is important
185 * to dump areas with ECC errors!
186 * For kernel internal usage it also might return -EUCLEAN
187 * to signal the caller that a bitflip has occurred and has
188 * been corrected by the ECC algorithm.
189 * Userspace software which accesses NAND this way
190 * must be aware of the fact that it deals with NAND
192 if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
194 if (copy_to_user(buf, kbuf, retlen)) {
199 total_retlen += retlen;
217 static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
220 struct mtd_file_info *mfi = file->private_data;
221 struct mtd_info *mtd = mfi->mtd;
225 size_t total_retlen=0;
229 pr_debug("MTD_write\n");
231 if (*ppos >= mtd->size)
234 if (*ppos + count > mtd->size)
235 count = mtd->size - *ppos;
240 kbuf = mtd_kmalloc_up_to(mtd, &size);
245 len = min_t(size_t, count, size);
247 if (copy_from_user(kbuf, buf, len)) {
253 case MTD_FILE_MODE_OTP_FACTORY:
256 case MTD_FILE_MODE_OTP_USER:
257 ret = mtd_write_user_prot_reg(mtd, *ppos, len,
261 case MTD_FILE_MODE_RAW:
263 struct mtd_oob_ops ops = {};
265 ops.mode = MTD_OPS_RAW;
271 ret = mtd_write_oob(mtd, *ppos, &ops);
277 ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
281 * Return -ENOSPC only if no data could be written at all.
282 * Otherwise just return the number of bytes that actually
285 if ((ret == -ENOSPC) && (total_retlen))
290 total_retlen += retlen;
302 } /* mtdchar_write */
304 /*======================================================================
306 IOCTL calls for getting device parameters.
308 ======================================================================*/
310 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
312 struct mtd_info *mtd = mfi->mtd;
316 case MTD_OTP_FACTORY:
317 if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
321 mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
324 if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
328 mfi->mode = MTD_FILE_MODE_OTP_USER;
331 mfi->mode = MTD_FILE_MODE_NORMAL;
340 static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
341 uint64_t start, uint32_t length, void __user *ptr,
342 uint32_t __user *retp)
344 struct mtd_info *master = mtd_get_master(mtd);
345 struct mtd_file_info *mfi = file->private_data;
346 struct mtd_oob_ops ops = {};
353 if (!master->_write_oob)
357 ops.ooboffs = start & (mtd->writesize - 1);
359 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
362 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
365 ops.oobbuf = memdup_user(ptr, length);
366 if (IS_ERR(ops.oobbuf))
367 return PTR_ERR(ops.oobbuf);
369 start &= ~((uint64_t)mtd->writesize - 1);
370 ret = mtd_write_oob(mtd, start, &ops);
372 if (ops.oobretlen > 0xFFFFFFFFU)
374 retlen = ops.oobretlen;
375 if (copy_to_user(retp, &retlen, sizeof(length)))
382 static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
383 uint64_t start, uint32_t length, void __user *ptr,
384 uint32_t __user *retp)
386 struct mtd_file_info *mfi = file->private_data;
387 struct mtd_oob_ops ops = {};
394 ops.ooboffs = start & (mtd->writesize - 1);
396 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
399 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
402 ops.oobbuf = kmalloc(length, GFP_KERNEL);
406 start &= ~((uint64_t)mtd->writesize - 1);
407 ret = mtd_read_oob(mtd, start, &ops);
409 if (put_user(ops.oobretlen, retp))
411 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
418 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
419 * data. For our userspace tools it is important to dump areas
421 * For kernel internal usage it also might return -EUCLEAN
422 * to signal the caller that a bitflip has occurred and has
423 * been corrected by the ECC algorithm.
425 * Note: currently the standard NAND function, nand_read_oob_std,
426 * does not calculate ECC for the OOB area, so do not rely on
427 * this behavior unless you have replaced it with your own.
429 if (mtd_is_bitflip_or_eccerr(ret))
436 * Copies (and truncates, if necessary) OOB layout information to the
437 * deprecated layout struct, nand_ecclayout_user. This is necessary only to
438 * support the deprecated API ioctl ECCGETLAYOUT while allowing all new
439 * functionality to use mtd_ooblayout_ops flexibly (i.e. mtd_ooblayout_ops
440 * can describe any kind of OOB layout with almost zero overhead from a
441 * memory usage point of view).
443 static int shrink_ecclayout(struct mtd_info *mtd,
444 struct nand_ecclayout_user *to)
446 struct mtd_oob_region oobregion;
447 int i, section = 0, ret;
452 memset(to, 0, sizeof(*to));
455 for (i = 0; i < MTD_MAX_ECCPOS_ENTRIES;) {
458 ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
466 eccpos = oobregion.offset;
467 for (; i < MTD_MAX_ECCPOS_ENTRIES &&
468 eccpos < oobregion.offset + oobregion.length; i++) {
469 to->eccpos[i] = eccpos++;
474 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
475 ret = mtd_ooblayout_free(mtd, i, &oobregion);
483 to->oobfree[i].offset = oobregion.offset;
484 to->oobfree[i].length = oobregion.length;
485 to->oobavail += to->oobfree[i].length;
491 static int get_oobinfo(struct mtd_info *mtd, struct nand_oobinfo *to)
493 struct mtd_oob_region oobregion;
494 int i, section = 0, ret;
499 memset(to, 0, sizeof(*to));
502 for (i = 0; i < ARRAY_SIZE(to->eccpos);) {
505 ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
513 if (oobregion.length + i > ARRAY_SIZE(to->eccpos))
516 eccpos = oobregion.offset;
517 for (; eccpos < oobregion.offset + oobregion.length; i++) {
518 to->eccpos[i] = eccpos++;
523 for (i = 0; i < 8; i++) {
524 ret = mtd_ooblayout_free(mtd, i, &oobregion);
532 to->oobfree[i][0] = oobregion.offset;
533 to->oobfree[i][1] = oobregion.length;
536 to->useecc = MTD_NANDECC_AUTOPLACE;
541 static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
542 struct blkpg_ioctl_arg *arg)
544 struct blkpg_partition p;
546 if (!capable(CAP_SYS_ADMIN))
549 if (copy_from_user(&p, arg->data, sizeof(p)))
553 case BLKPG_ADD_PARTITION:
555 /* Only master mtd device must be used to add partitions */
556 if (mtd_is_partition(mtd))
559 /* Sanitize user input */
560 p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
562 return mtd_add_partition(mtd, p.devname, p.start, p.length);
564 case BLKPG_DEL_PARTITION:
569 return mtd_del_partition(mtd, p.pno);
576 static void adjust_oob_length(struct mtd_info *mtd, uint64_t start,
577 struct mtd_oob_ops *ops)
579 uint32_t start_page, end_page;
582 if (ops->len == 0 || ops->ooblen == 0)
585 start_page = mtd_div_by_ws(start, mtd);
586 end_page = mtd_div_by_ws(start + ops->len - 1, mtd);
587 oob_per_page = mtd_oobavail(mtd, ops);
589 ops->ooblen = min_t(size_t, ops->ooblen,
590 (end_page - start_page + 1) * oob_per_page);
593 static int mtdchar_write_ioctl(struct mtd_info *mtd,
594 struct mtd_write_req __user *argp)
596 struct mtd_info *master = mtd_get_master(mtd);
597 struct mtd_write_req req;
598 const void __user *usr_data, *usr_oob;
599 uint8_t *datbuf = NULL, *oobbuf = NULL;
600 size_t datbuf_len, oobbuf_len;
603 if (copy_from_user(&req, argp, sizeof(req)))
606 usr_data = (const void __user *)(uintptr_t)req.usr_data;
607 usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
609 if (!master->_write_oob)
618 req.len &= 0xffffffff;
619 req.ooblen &= 0xffffffff;
621 if (req.start + req.len > mtd->size)
624 datbuf_len = min_t(size_t, req.len, mtd->erasesize);
625 if (datbuf_len > 0) {
626 datbuf = kvmalloc(datbuf_len, GFP_KERNEL);
631 oobbuf_len = min_t(size_t, req.ooblen, mtd->erasesize);
632 if (oobbuf_len > 0) {
633 oobbuf = kvmalloc(oobbuf_len, GFP_KERNEL);
640 while (req.len > 0 || (!usr_data && req.ooblen > 0)) {
641 struct mtd_oob_ops ops = {
643 .len = min_t(size_t, req.len, datbuf_len),
644 .ooblen = min_t(size_t, req.ooblen, oobbuf_len),
650 * Shorten non-page-aligned, eraseblock-sized writes so that
651 * the write ends on an eraseblock boundary. This is necessary
652 * for adjust_oob_length() to properly handle non-page-aligned
655 if (ops.len == mtd->erasesize)
656 ops.len -= mtd_mod_by_ws(req.start + ops.len, mtd);
659 * For writes which are not OOB-only, adjust the amount of OOB
660 * data written according to the number of data pages written.
661 * This is necessary to prevent OOB data from being skipped
662 * over in data+OOB writes requiring multiple mtd_write_oob()
663 * calls to be completed.
665 adjust_oob_length(mtd, req.start, &ops);
667 if (copy_from_user(datbuf, usr_data, ops.len) ||
668 copy_from_user(oobbuf, usr_oob, ops.ooblen)) {
673 ret = mtd_write_oob(mtd, req.start, &ops);
677 req.start += ops.retlen;
678 req.len -= ops.retlen;
679 usr_data += ops.retlen;
681 req.ooblen -= ops.oobretlen;
682 usr_oob += ops.oobretlen;
691 static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
693 struct mtd_file_info *mfi = file->private_data;
694 struct mtd_info *mtd = mfi->mtd;
695 struct mtd_info *master = mtd_get_master(mtd);
696 void __user *argp = (void __user *)arg;
698 struct mtd_info_user info;
700 pr_debug("MTD_ioctl\n");
703 * Check the file mode to require "dangerous" commands to have write
707 /* "safe" commands */
708 case MEMGETREGIONCOUNT:
709 case MEMGETREGIONINFO:
717 case OTPGETREGIONCOUNT:
718 case OTPGETREGIONINFO:
726 /* "dangerous" commands */
737 if (!(file->f_mode & FMODE_WRITE))
746 case MEMGETREGIONCOUNT:
747 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
751 case MEMGETREGIONINFO:
754 struct mtd_erase_region_info *kr;
755 struct region_info_user __user *ur = argp;
757 if (get_user(ur_idx, &(ur->regionindex)))
760 if (ur_idx >= mtd->numeraseregions)
763 kr = &(mtd->eraseregions[ur_idx]);
765 if (put_user(kr->offset, &(ur->offset))
766 || put_user(kr->erasesize, &(ur->erasesize))
767 || put_user(kr->numblocks, &(ur->numblocks)))
774 memset(&info, 0, sizeof(info));
775 info.type = mtd->type;
776 info.flags = mtd->flags;
777 info.size = mtd->size;
778 info.erasesize = mtd->erasesize;
779 info.writesize = mtd->writesize;
780 info.oobsize = mtd->oobsize;
781 /* The below field is obsolete */
783 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
790 struct erase_info *erase;
792 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
796 if (cmd == MEMERASE64) {
797 struct erase_info_user64 einfo64;
799 if (copy_from_user(&einfo64, argp,
800 sizeof(struct erase_info_user64))) {
804 erase->addr = einfo64.start;
805 erase->len = einfo64.length;
807 struct erase_info_user einfo32;
809 if (copy_from_user(&einfo32, argp,
810 sizeof(struct erase_info_user))) {
814 erase->addr = einfo32.start;
815 erase->len = einfo32.length;
818 ret = mtd_erase(mtd, erase);
826 struct mtd_oob_buf buf;
827 struct mtd_oob_buf __user *buf_user = argp;
829 /* NOTE: writes return length to buf_user->length */
830 if (copy_from_user(&buf, argp, sizeof(buf)))
833 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
834 buf.ptr, &buf_user->length);
840 struct mtd_oob_buf buf;
841 struct mtd_oob_buf __user *buf_user = argp;
843 /* NOTE: writes return length to buf_user->start */
844 if (copy_from_user(&buf, argp, sizeof(buf)))
847 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
848 buf.ptr, &buf_user->start);
854 struct mtd_oob_buf64 buf;
855 struct mtd_oob_buf64 __user *buf_user = argp;
857 if (copy_from_user(&buf, argp, sizeof(buf)))
860 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
861 (void __user *)(uintptr_t)buf.usr_ptr,
868 struct mtd_oob_buf64 buf;
869 struct mtd_oob_buf64 __user *buf_user = argp;
871 if (copy_from_user(&buf, argp, sizeof(buf)))
874 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
875 (void __user *)(uintptr_t)buf.usr_ptr,
882 ret = mtdchar_write_ioctl(mtd,
883 (struct mtd_write_req __user *)arg);
889 struct erase_info_user einfo;
891 if (copy_from_user(&einfo, argp, sizeof(einfo)))
894 ret = mtd_lock(mtd, einfo.start, einfo.length);
900 struct erase_info_user einfo;
902 if (copy_from_user(&einfo, argp, sizeof(einfo)))
905 ret = mtd_unlock(mtd, einfo.start, einfo.length);
911 struct erase_info_user einfo;
913 if (copy_from_user(&einfo, argp, sizeof(einfo)))
916 ret = mtd_is_locked(mtd, einfo.start, einfo.length);
920 /* Legacy interface */
923 struct nand_oobinfo oi;
925 if (!master->ooblayout)
928 ret = get_oobinfo(mtd, &oi);
932 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
941 if (copy_from_user(&offs, argp, sizeof(loff_t)))
943 return mtd_block_isbad(mtd, offs);
950 if (copy_from_user(&offs, argp, sizeof(loff_t)))
952 return mtd_block_markbad(mtd, offs);
958 if (copy_from_user(&mode, argp, sizeof(int)))
961 mfi->mode = MTD_FILE_MODE_NORMAL;
963 ret = otp_select_filemode(mfi, mode);
969 case OTPGETREGIONCOUNT:
970 case OTPGETREGIONINFO:
972 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
977 case MTD_FILE_MODE_OTP_FACTORY:
978 ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
980 case MTD_FILE_MODE_OTP_USER:
981 ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
988 if (cmd == OTPGETREGIONCOUNT) {
989 int nbr = retlen / sizeof(struct otp_info);
990 ret = copy_to_user(argp, &nbr, sizeof(int));
992 ret = copy_to_user(argp, buf, retlen);
1003 struct otp_info oinfo;
1005 if (mfi->mode != MTD_FILE_MODE_OTP_USER)
1007 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
1010 ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
1012 ret = mtd_erase_user_prot_reg(mtd, oinfo.start, oinfo.length);
1016 /* This ioctl is being deprecated - it truncates the ECC layout */
1019 struct nand_ecclayout_user *usrlay;
1021 if (!master->ooblayout)
1024 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
1028 shrink_ecclayout(mtd, usrlay);
1030 if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
1038 if (copy_to_user(argp, &mtd->ecc_stats,
1039 sizeof(struct mtd_ecc_stats)))
1049 case MTD_FILE_MODE_OTP_FACTORY:
1050 case MTD_FILE_MODE_OTP_USER:
1051 ret = otp_select_filemode(mfi, arg);
1054 case MTD_FILE_MODE_RAW:
1055 if (!mtd_has_oob(mtd))
1060 case MTD_FILE_MODE_NORMAL:
1071 struct blkpg_ioctl_arg __user *blk_arg = argp;
1072 struct blkpg_ioctl_arg a;
1074 if (copy_from_user(&a, blk_arg, sizeof(a)))
1077 ret = mtdchar_blkpg_ioctl(mtd, &a);
1083 /* No reread partition feature. Just return ok */
1090 } /* memory_ioctl */
1092 static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1094 struct mtd_file_info *mfi = file->private_data;
1095 struct mtd_info *mtd = mfi->mtd;
1096 struct mtd_info *master = mtd_get_master(mtd);
1099 mutex_lock(&master->master.chrdev_lock);
1100 ret = mtdchar_ioctl(file, cmd, arg);
1101 mutex_unlock(&master->master.chrdev_lock);
1106 #ifdef CONFIG_COMPAT
1108 struct mtd_oob_buf32 {
1111 compat_caddr_t ptr; /* unsigned char* */
1114 #define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1115 #define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1117 static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1120 struct mtd_file_info *mfi = file->private_data;
1121 struct mtd_info *mtd = mfi->mtd;
1122 struct mtd_info *master = mtd_get_master(mtd);
1123 void __user *argp = compat_ptr(arg);
1126 mutex_lock(&master->master.chrdev_lock);
1131 struct mtd_oob_buf32 buf;
1132 struct mtd_oob_buf32 __user *buf_user = argp;
1134 if (!(file->f_mode & FMODE_WRITE)) {
1139 if (copy_from_user(&buf, argp, sizeof(buf)))
1142 ret = mtdchar_writeoob(file, mtd, buf.start,
1143 buf.length, compat_ptr(buf.ptr),
1150 struct mtd_oob_buf32 buf;
1151 struct mtd_oob_buf32 __user *buf_user = argp;
1153 /* NOTE: writes return length to buf->start */
1154 if (copy_from_user(&buf, argp, sizeof(buf)))
1157 ret = mtdchar_readoob(file, mtd, buf.start,
1158 buf.length, compat_ptr(buf.ptr),
1165 /* Convert from blkpg_compat_ioctl_arg to blkpg_ioctl_arg */
1166 struct blkpg_compat_ioctl_arg __user *uarg = argp;
1167 struct blkpg_compat_ioctl_arg compat_arg;
1168 struct blkpg_ioctl_arg a;
1170 if (copy_from_user(&compat_arg, uarg, sizeof(compat_arg))) {
1175 memset(&a, 0, sizeof(a));
1176 a.op = compat_arg.op;
1177 a.flags = compat_arg.flags;
1178 a.datalen = compat_arg.datalen;
1179 a.data = compat_ptr(compat_arg.data);
1181 ret = mtdchar_blkpg_ioctl(mtd, &a);
1186 ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1189 mutex_unlock(&master->master.chrdev_lock);
1194 #endif /* CONFIG_COMPAT */
1197 * try to determine where a shared mapping can be made
1198 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1202 static unsigned long mtdchar_get_unmapped_area(struct file *file,
1205 unsigned long pgoff,
1206 unsigned long flags)
1208 struct mtd_file_info *mfi = file->private_data;
1209 struct mtd_info *mtd = mfi->mtd;
1210 unsigned long offset;
1214 return (unsigned long) -EINVAL;
1216 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1217 return (unsigned long) -EINVAL;
1219 offset = pgoff << PAGE_SHIFT;
1220 if (offset > mtd->size - len)
1221 return (unsigned long) -EINVAL;
1223 ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1224 return ret == -EOPNOTSUPP ? -ENODEV : ret;
1227 static unsigned mtdchar_mmap_capabilities(struct file *file)
1229 struct mtd_file_info *mfi = file->private_data;
1231 return mtd_mmap_capabilities(mfi->mtd);
1236 * set up a mapping for shared memory segments
1238 static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1241 struct mtd_file_info *mfi = file->private_data;
1242 struct mtd_info *mtd = mfi->mtd;
1243 struct map_info *map = mtd->priv;
1245 /* This is broken because it assumes the MTD device is map-based
1246 and that mtd->priv is a valid struct map_info. It should be
1247 replaced with something that uses the mtd_get_unmapped_area()
1248 operation properly. */
1249 if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1250 #ifdef pgprot_noncached
1251 if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1252 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1254 return vm_iomap_memory(vma, map->phys, map->size);
1258 return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1262 static const struct file_operations mtd_fops = {
1263 .owner = THIS_MODULE,
1264 .llseek = mtdchar_lseek,
1265 .read = mtdchar_read,
1266 .write = mtdchar_write,
1267 .unlocked_ioctl = mtdchar_unlocked_ioctl,
1268 #ifdef CONFIG_COMPAT
1269 .compat_ioctl = mtdchar_compat_ioctl,
1271 .open = mtdchar_open,
1272 .release = mtdchar_close,
1273 .mmap = mtdchar_mmap,
1275 .get_unmapped_area = mtdchar_get_unmapped_area,
1276 .mmap_capabilities = mtdchar_mmap_capabilities,
1280 int __init init_mtdchar(void)
1284 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1287 pr_err("Can't allocate major number %d for MTD\n",
1295 void __exit cleanup_mtdchar(void)
1297 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1300 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);