2 * Copyright (c) International Business Machines Corp., 2006
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
12 * the 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 * Author: Artem Bityutskiy (Битюцкий Артём)
22 * This file includes implementation of UBI character device operations.
24 * There are two kinds of character devices in UBI: UBI character devices and
25 * UBI volume character devices. UBI character devices allow users to
26 * manipulate whole volumes: create, remove, and re-size them. Volume character
27 * devices provide volume I/O capabilities.
29 * Major and minor numbers are assigned dynamically to both UBI and volume
32 * Well, there is the third kind of character devices - the UBI control
33 * character device, which allows to manipulate by UBI devices - create and
34 * delete them. In other words, it is used for attaching and detaching MTD
38 #include <linux/module.h>
39 #include <linux/stat.h>
40 #include <linux/slab.h>
41 #include <linux/ioctl.h>
42 #include <linux/capability.h>
43 #include <linux/uaccess.h>
44 #include <linux/compat.h>
45 #include <linux/math64.h>
46 #include <mtd/ubi-user.h>
50 * get_exclusive - get exclusive access to an UBI volume.
51 * @desc: volume descriptor
53 * This function changes UBI volume open mode to "exclusive". Returns previous
54 * mode value (positive integer) in case of success and a negative error code
57 static int get_exclusive(struct ubi_volume_desc *desc)
60 struct ubi_volume *vol = desc->vol;
62 spin_lock(&vol->ubi->volumes_lock);
63 users = vol->readers + vol->writers + vol->exclusive;
64 ubi_assert(users > 0);
66 ubi_err("%d users for volume %d", users, vol->vol_id);
69 vol->readers = vol->writers = 0;
72 desc->mode = UBI_EXCLUSIVE;
74 spin_unlock(&vol->ubi->volumes_lock);
80 * revoke_exclusive - revoke exclusive mode.
81 * @desc: volume descriptor
82 * @mode: new mode to switch to
84 static void revoke_exclusive(struct ubi_volume_desc *desc, int mode)
86 struct ubi_volume *vol = desc->vol;
88 spin_lock(&vol->ubi->volumes_lock);
89 ubi_assert(vol->readers == 0 && vol->writers == 0);
90 ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE);
92 if (mode == UBI_READONLY)
94 else if (mode == UBI_READWRITE)
98 spin_unlock(&vol->ubi->volumes_lock);
103 static int vol_cdev_open(struct inode *inode, struct file *file)
105 struct ubi_volume_desc *desc;
106 int vol_id = iminor(inode) - 1, mode, ubi_num;
108 ubi_num = ubi_major2num(imajor(inode));
112 if (file->f_mode & FMODE_WRITE)
113 mode = UBI_READWRITE;
117 dbg_gen("open device %d, volume %d, mode %d",
118 ubi_num, vol_id, mode);
120 desc = ubi_open_volume(ubi_num, vol_id, mode);
122 return PTR_ERR(desc);
124 file->private_data = desc;
128 static int vol_cdev_release(struct inode *inode, struct file *file)
130 struct ubi_volume_desc *desc = file->private_data;
131 struct ubi_volume *vol = desc->vol;
133 dbg_gen("release device %d, volume %d, mode %d",
134 vol->ubi->ubi_num, vol->vol_id, desc->mode);
137 ubi_warn("update of volume %d not finished, volume is damaged",
139 ubi_assert(!vol->changing_leb);
142 } else if (vol->changing_leb) {
143 dbg_gen("only %lld of %lld bytes received for atomic LEB change for volume %d:%d, cancel",
144 vol->upd_received, vol->upd_bytes, vol->ubi->ubi_num,
146 vol->changing_leb = 0;
150 ubi_close_volume(desc);
154 static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin)
156 struct ubi_volume_desc *desc = file->private_data;
157 struct ubi_volume *vol = desc->vol;
160 /* Update is in progress, seeking is prohibited */
165 return fixed_size_llseek(file, offset, origin, vol->used_bytes);
168 static int vol_cdev_fsync(struct file *file, loff_t start, loff_t end,
171 struct ubi_volume_desc *desc = file->private_data;
172 struct ubi_device *ubi = desc->vol->ubi;
173 struct inode *inode = file_inode(file);
175 mutex_lock(&inode->i_mutex);
176 err = ubi_sync(ubi->ubi_num);
177 mutex_unlock(&inode->i_mutex);
182 static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count,
185 struct ubi_volume_desc *desc = file->private_data;
186 struct ubi_volume *vol = desc->vol;
187 struct ubi_device *ubi = vol->ubi;
188 int err, lnum, off, len, tbuf_size;
189 size_t count_save = count;
192 dbg_gen("read %zd bytes from offset %lld of volume %d",
193 count, *offp, vol->vol_id);
199 if (vol->upd_marker) {
200 ubi_err("damaged volume, update marker is set");
203 if (*offp == vol->used_bytes || count == 0)
207 dbg_gen("read from corrupted volume %d", vol->vol_id);
209 if (*offp + count > vol->used_bytes)
210 count_save = count = vol->used_bytes - *offp;
212 tbuf_size = vol->usable_leb_size;
213 if (count < tbuf_size)
214 tbuf_size = ALIGN(count, ubi->min_io_size);
215 tbuf = vmalloc(tbuf_size);
219 len = count > tbuf_size ? tbuf_size : count;
220 lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
225 if (off + len >= vol->usable_leb_size)
226 len = vol->usable_leb_size - off;
228 err = ubi_eba_read_leb(ubi, vol, lnum, tbuf, off, len, 0);
233 if (off == vol->usable_leb_size) {
235 off -= vol->usable_leb_size;
241 err = copy_to_user(buf, tbuf, len);
248 len = count > tbuf_size ? tbuf_size : count;
252 return err ? err : count_save - count;
256 * This function allows to directly write to dynamic UBI volumes, without
257 * issuing the volume update operation.
259 static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf,
260 size_t count, loff_t *offp)
262 struct ubi_volume_desc *desc = file->private_data;
263 struct ubi_volume *vol = desc->vol;
264 struct ubi_device *ubi = vol->ubi;
265 int lnum, off, len, tbuf_size, err = 0;
266 size_t count_save = count;
269 if (!vol->direct_writes)
272 dbg_gen("requested: write %zd bytes to offset %lld of volume %u",
273 count, *offp, vol->vol_id);
275 if (vol->vol_type == UBI_STATIC_VOLUME)
278 lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
279 if (off & (ubi->min_io_size - 1)) {
280 ubi_err("unaligned position");
284 if (*offp + count > vol->used_bytes)
285 count_save = count = vol->used_bytes - *offp;
287 /* We can write only in fractions of the minimum I/O unit */
288 if (count & (ubi->min_io_size - 1)) {
289 ubi_err("unaligned write length");
293 tbuf_size = vol->usable_leb_size;
294 if (count < tbuf_size)
295 tbuf_size = ALIGN(count, ubi->min_io_size);
296 tbuf = vmalloc(tbuf_size);
300 len = count > tbuf_size ? tbuf_size : count;
305 if (off + len >= vol->usable_leb_size)
306 len = vol->usable_leb_size - off;
308 err = copy_from_user(tbuf, buf, len);
314 err = ubi_eba_write_leb(ubi, vol, lnum, tbuf, off, len);
319 if (off == vol->usable_leb_size) {
321 off -= vol->usable_leb_size;
327 len = count > tbuf_size ? tbuf_size : count;
331 return err ? err : count_save - count;
334 static ssize_t vol_cdev_write(struct file *file, const char __user *buf,
335 size_t count, loff_t *offp)
338 struct ubi_volume_desc *desc = file->private_data;
339 struct ubi_volume *vol = desc->vol;
340 struct ubi_device *ubi = vol->ubi;
342 if (!vol->updating && !vol->changing_leb)
343 return vol_cdev_direct_write(file, buf, count, offp);
346 err = ubi_more_update_data(ubi, vol, buf, count);
348 err = ubi_more_leb_change_data(ubi, vol, buf, count);
351 ubi_err("cannot accept more %zd bytes of data, error %d",
358 * The operation is finished, @err contains number of actually
363 if (vol->changing_leb) {
364 revoke_exclusive(desc, UBI_READWRITE);
368 err = ubi_check_volume(ubi, vol->vol_id);
373 ubi_warn("volume %d on UBI device %d is corrupted",
374 vol->vol_id, ubi->ubi_num);
378 ubi_volume_notify(ubi, vol, UBI_VOLUME_UPDATED);
379 revoke_exclusive(desc, UBI_READWRITE);
385 static long vol_cdev_ioctl(struct file *file, unsigned int cmd,
389 struct ubi_volume_desc *desc = file->private_data;
390 struct ubi_volume *vol = desc->vol;
391 struct ubi_device *ubi = vol->ubi;
392 void __user *argp = (void __user *)arg;
395 /* Volume update command */
398 int64_t bytes, rsvd_bytes;
400 if (!capable(CAP_SYS_RESOURCE)) {
405 err = copy_from_user(&bytes, argp, sizeof(int64_t));
411 if (desc->mode == UBI_READONLY) {
416 rsvd_bytes = (long long)vol->reserved_pebs *
417 ubi->leb_size-vol->data_pad;
418 if (bytes < 0 || bytes > rsvd_bytes) {
423 err = get_exclusive(desc);
427 err = ubi_start_update(ubi, vol, bytes);
429 revoke_exclusive(desc, UBI_READWRITE);
433 /* Atomic logical eraseblock change command */
436 struct ubi_leb_change_req req;
438 err = copy_from_user(&req, argp,
439 sizeof(struct ubi_leb_change_req));
445 if (desc->mode == UBI_READONLY ||
446 vol->vol_type == UBI_STATIC_VOLUME) {
451 /* Validate the request */
453 if (req.lnum < 0 || req.lnum >= vol->reserved_pebs ||
454 req.bytes < 0 || req.lnum >= vol->usable_leb_size)
457 err = get_exclusive(desc);
461 err = ubi_start_leb_change(ubi, vol, &req);
463 revoke_exclusive(desc, UBI_READWRITE);
467 /* Logical eraseblock erasure command */
472 err = get_user(lnum, (__user int32_t *)argp);
478 if (desc->mode == UBI_READONLY ||
479 vol->vol_type == UBI_STATIC_VOLUME) {
484 if (lnum < 0 || lnum >= vol->reserved_pebs) {
489 dbg_gen("erase LEB %d:%d", vol->vol_id, lnum);
490 err = ubi_eba_unmap_leb(ubi, vol, lnum);
494 err = ubi_wl_flush(ubi, UBI_ALL, UBI_ALL);
498 /* Logical eraseblock map command */
501 struct ubi_map_req req;
503 err = copy_from_user(&req, argp, sizeof(struct ubi_map_req));
508 err = ubi_leb_map(desc, req.lnum);
512 /* Logical eraseblock un-map command */
517 err = get_user(lnum, (__user int32_t *)argp);
522 err = ubi_leb_unmap(desc, lnum);
526 /* Check if logical eraseblock is mapped command */
531 err = get_user(lnum, (__user int32_t *)argp);
536 err = ubi_is_mapped(desc, lnum);
540 /* Set volume property command */
541 case UBI_IOCSETVOLPROP:
543 struct ubi_set_vol_prop_req req;
545 err = copy_from_user(&req, argp,
546 sizeof(struct ubi_set_vol_prop_req));
551 switch (req.property) {
552 case UBI_VOL_PROP_DIRECT_WRITE:
553 mutex_lock(&ubi->device_mutex);
554 desc->vol->direct_writes = !!req.value;
555 mutex_unlock(&ubi->device_mutex);
564 /* Create a R/O block device on top of the UBI volume */
565 case UBI_IOCVOLCRBLK:
567 struct ubi_volume_info vi;
569 ubi_get_volume_info(desc, &vi);
570 err = ubiblock_create(&vi);
574 /* Remove the R/O block device */
575 case UBI_IOCVOLRMBLK:
577 struct ubi_volume_info vi;
579 ubi_get_volume_info(desc, &vi);
580 err = ubiblock_remove(&vi);
592 * verify_mkvol_req - verify volume creation request.
593 * @ubi: UBI device description object
594 * @req: the request to check
596 * This function zero if the request is correct, and %-EINVAL if not.
598 static int verify_mkvol_req(const struct ubi_device *ubi,
599 const struct ubi_mkvol_req *req)
601 int n, err = -EINVAL;
603 if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 ||
607 if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) &&
608 req->vol_id != UBI_VOL_NUM_AUTO)
611 if (req->alignment == 0)
617 if (req->vol_type != UBI_DYNAMIC_VOLUME &&
618 req->vol_type != UBI_STATIC_VOLUME)
621 if (req->alignment > ubi->leb_size)
624 n = req->alignment & (ubi->min_io_size - 1);
625 if (req->alignment != 1 && n)
628 if (!req->name[0] || !req->name_len)
631 if (req->name_len > UBI_VOL_NAME_MAX) {
636 n = strnlen(req->name, req->name_len + 1);
637 if (n != req->name_len)
643 ubi_err("bad volume creation request");
644 ubi_dump_mkvol_req(req);
649 * verify_rsvol_req - verify volume re-size request.
650 * @ubi: UBI device description object
651 * @req: the request to check
653 * This function returns zero if the request is correct, and %-EINVAL if not.
655 static int verify_rsvol_req(const struct ubi_device *ubi,
656 const struct ubi_rsvol_req *req)
661 if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots)
668 * rename_volumes - rename UBI volumes.
669 * @ubi: UBI device description object
670 * @req: volumes re-name request
672 * This is a helper function for the volume re-name IOCTL which validates the
673 * the request, opens the volume and calls corresponding volumes management
674 * function. Returns zero in case of success and a negative error code in case
677 static int rename_volumes(struct ubi_device *ubi,
678 struct ubi_rnvol_req *req)
681 struct list_head rename_list;
682 struct ubi_rename_entry *re, *re1;
684 if (req->count < 0 || req->count > UBI_MAX_RNVOL)
690 /* Validate volume IDs and names in the request */
691 for (i = 0; i < req->count; i++) {
692 if (req->ents[i].vol_id < 0 ||
693 req->ents[i].vol_id >= ubi->vtbl_slots)
695 if (req->ents[i].name_len < 0)
697 if (req->ents[i].name_len > UBI_VOL_NAME_MAX)
698 return -ENAMETOOLONG;
699 req->ents[i].name[req->ents[i].name_len] = '\0';
700 n = strlen(req->ents[i].name);
701 if (n != req->ents[i].name_len)
705 /* Make sure volume IDs and names are unique */
706 for (i = 0; i < req->count - 1; i++) {
707 for (n = i + 1; n < req->count; n++) {
708 if (req->ents[i].vol_id == req->ents[n].vol_id) {
709 ubi_err("duplicated volume id %d",
710 req->ents[i].vol_id);
713 if (!strcmp(req->ents[i].name, req->ents[n].name)) {
714 ubi_err("duplicated volume name \"%s\"",
721 /* Create the re-name list */
722 INIT_LIST_HEAD(&rename_list);
723 for (i = 0; i < req->count; i++) {
724 int vol_id = req->ents[i].vol_id;
725 int name_len = req->ents[i].name_len;
726 const char *name = req->ents[i].name;
728 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
734 re->desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_READWRITE);
735 if (IS_ERR(re->desc)) {
736 err = PTR_ERR(re->desc);
737 ubi_err("cannot open volume %d, error %d", vol_id, err);
742 /* Skip this re-naming if the name does not really change */
743 if (re->desc->vol->name_len == name_len &&
744 !memcmp(re->desc->vol->name, name, name_len)) {
745 ubi_close_volume(re->desc);
750 re->new_name_len = name_len;
751 memcpy(re->new_name, name, name_len);
752 list_add_tail(&re->list, &rename_list);
753 dbg_gen("will rename volume %d from \"%s\" to \"%s\"",
754 vol_id, re->desc->vol->name, name);
757 if (list_empty(&rename_list))
760 /* Find out the volumes which have to be removed */
761 list_for_each_entry(re, &rename_list, list) {
762 struct ubi_volume_desc *desc;
763 int no_remove_needed = 0;
766 * Volume @re->vol_id is going to be re-named to
767 * @re->new_name, while its current name is @name. If a volume
768 * with name @re->new_name currently exists, it has to be
769 * removed, unless it is also re-named in the request (@req).
771 list_for_each_entry(re1, &rename_list, list) {
772 if (re->new_name_len == re1->desc->vol->name_len &&
773 !memcmp(re->new_name, re1->desc->vol->name,
774 re1->desc->vol->name_len)) {
775 no_remove_needed = 1;
780 if (no_remove_needed)
784 * It seems we need to remove volume with name @re->new_name,
787 desc = ubi_open_volume_nm(ubi->ubi_num, re->new_name,
792 /* Re-naming into a non-existing volume name */
795 /* The volume exists but busy, or an error occurred */
796 ubi_err("cannot open volume \"%s\", error %d",
801 re1 = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
804 ubi_close_volume(desc);
810 list_add(&re1->list, &rename_list);
811 dbg_gen("will remove volume %d, name \"%s\"",
812 re1->desc->vol->vol_id, re1->desc->vol->name);
815 mutex_lock(&ubi->device_mutex);
816 err = ubi_rename_volumes(ubi, &rename_list);
817 mutex_unlock(&ubi->device_mutex);
820 list_for_each_entry_safe(re, re1, &rename_list, list) {
821 ubi_close_volume(re->desc);
828 static long ubi_cdev_ioctl(struct file *file, unsigned int cmd,
832 struct ubi_device *ubi;
833 struct ubi_volume_desc *desc;
834 void __user *argp = (void __user *)arg;
836 if (!capable(CAP_SYS_RESOURCE))
839 ubi = ubi_get_by_major(imajor(file->f_mapping->host));
844 /* Create volume command */
847 struct ubi_mkvol_req req;
849 dbg_gen("create volume");
850 err = copy_from_user(&req, argp, sizeof(struct ubi_mkvol_req));
856 err = verify_mkvol_req(ubi, &req);
860 mutex_lock(&ubi->device_mutex);
861 err = ubi_create_volume(ubi, &req);
862 mutex_unlock(&ubi->device_mutex);
866 err = put_user(req.vol_id, (__user int32_t *)argp);
873 /* Remove volume command */
878 dbg_gen("remove volume");
879 err = get_user(vol_id, (__user int32_t *)argp);
885 desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
891 mutex_lock(&ubi->device_mutex);
892 err = ubi_remove_volume(desc, 0);
893 mutex_unlock(&ubi->device_mutex);
896 * The volume is deleted (unless an error occurred), and the
897 * 'struct ubi_volume' object will be freed when
898 * 'ubi_close_volume()' will call 'put_device()'.
900 ubi_close_volume(desc);
904 /* Re-size volume command */
908 struct ubi_rsvol_req req;
910 dbg_gen("re-size volume");
911 err = copy_from_user(&req, argp, sizeof(struct ubi_rsvol_req));
917 err = verify_rsvol_req(ubi, &req);
921 desc = ubi_open_volume(ubi->ubi_num, req.vol_id, UBI_EXCLUSIVE);
927 pebs = div_u64(req.bytes + desc->vol->usable_leb_size - 1,
928 desc->vol->usable_leb_size);
930 mutex_lock(&ubi->device_mutex);
931 err = ubi_resize_volume(desc, pebs);
932 mutex_unlock(&ubi->device_mutex);
933 ubi_close_volume(desc);
937 /* Re-name volumes command */
940 struct ubi_rnvol_req *req;
942 dbg_gen("re-name volumes");
943 req = kmalloc(sizeof(struct ubi_rnvol_req), GFP_KERNEL);
949 err = copy_from_user(req, argp, sizeof(struct ubi_rnvol_req));
956 err = rename_volumes(ubi, req);
970 static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd,
974 void __user *argp = (void __user *)arg;
976 if (!capable(CAP_SYS_RESOURCE))
980 /* Attach an MTD device command */
983 struct ubi_attach_req req;
984 struct mtd_info *mtd;
986 dbg_gen("attach MTD device");
987 err = copy_from_user(&req, argp, sizeof(struct ubi_attach_req));
993 if (req.mtd_num < 0 ||
994 (req.ubi_num < 0 && req.ubi_num != UBI_DEV_NUM_AUTO)) {
999 mtd = get_mtd_device(NULL, req.mtd_num);
1006 * Note, further request verification is done by
1007 * 'ubi_attach_mtd_dev()'.
1009 mutex_lock(&ubi_devices_mutex);
1010 err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset,
1011 req.max_beb_per1024);
1012 mutex_unlock(&ubi_devices_mutex);
1014 put_mtd_device(mtd);
1016 /* @err contains UBI device number */
1017 err = put_user(err, (__user int32_t *)argp);
1022 /* Detach an MTD device command */
1027 dbg_gen("detach MTD device");
1028 err = get_user(ubi_num, (__user int32_t *)argp);
1034 mutex_lock(&ubi_devices_mutex);
1035 err = ubi_detach_mtd_dev(ubi_num, 0);
1036 mutex_unlock(&ubi_devices_mutex);
1048 #ifdef CONFIG_COMPAT
1049 static long vol_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1052 unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1054 return vol_cdev_ioctl(file, cmd, translated_arg);
1057 static long ubi_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1060 unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1062 return ubi_cdev_ioctl(file, cmd, translated_arg);
1065 static long ctrl_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1068 unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1070 return ctrl_cdev_ioctl(file, cmd, translated_arg);
1073 #define vol_cdev_compat_ioctl NULL
1074 #define ubi_cdev_compat_ioctl NULL
1075 #define ctrl_cdev_compat_ioctl NULL
1078 /* UBI volume character device operations */
1079 const struct file_operations ubi_vol_cdev_operations = {
1080 .owner = THIS_MODULE,
1081 .open = vol_cdev_open,
1082 .release = vol_cdev_release,
1083 .llseek = vol_cdev_llseek,
1084 .read = vol_cdev_read,
1085 .write = vol_cdev_write,
1086 .fsync = vol_cdev_fsync,
1087 .unlocked_ioctl = vol_cdev_ioctl,
1088 .compat_ioctl = vol_cdev_compat_ioctl,
1091 /* UBI character device operations */
1092 const struct file_operations ubi_cdev_operations = {
1093 .owner = THIS_MODULE,
1094 .llseek = no_llseek,
1095 .unlocked_ioctl = ubi_cdev_ioctl,
1096 .compat_ioctl = ubi_cdev_compat_ioctl,
1099 /* UBI control character device operations */
1100 const struct file_operations ubi_ctrl_cdev_operations = {
1101 .owner = THIS_MODULE,
1102 .unlocked_ioctl = ctrl_cdev_ioctl,
1103 .compat_ioctl = ctrl_cdev_compat_ioctl,
1104 .llseek = no_llseek,