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/ioctl.h>
41 #include <linux/capability.h>
42 #include <linux/uaccess.h>
43 #include <linux/compat.h>
44 #include <linux/math64.h>
45 #include <mtd/ubi-user.h>
49 * get_exclusive - get exclusive access to an UBI volume.
50 * @desc: volume descriptor
52 * This function changes UBI volume open mode to "exclusive". Returns previous
53 * mode value (positive integer) in case of success and a negative error code
56 static int get_exclusive(struct ubi_volume_desc *desc)
59 struct ubi_volume *vol = desc->vol;
61 spin_lock(&vol->ubi->volumes_lock);
62 users = vol->readers + vol->writers + vol->exclusive;
63 ubi_assert(users > 0);
65 dbg_err("%d users for volume %d", users, vol->vol_id);
68 vol->readers = vol->writers = 0;
71 desc->mode = UBI_EXCLUSIVE;
73 spin_unlock(&vol->ubi->volumes_lock);
79 * revoke_exclusive - revoke exclusive mode.
80 * @desc: volume descriptor
81 * @mode: new mode to switch to
83 static void revoke_exclusive(struct ubi_volume_desc *desc, int mode)
85 struct ubi_volume *vol = desc->vol;
87 spin_lock(&vol->ubi->volumes_lock);
88 ubi_assert(vol->readers == 0 && vol->writers == 0);
89 ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE);
91 if (mode == UBI_READONLY)
93 else if (mode == UBI_READWRITE)
97 spin_unlock(&vol->ubi->volumes_lock);
102 static int vol_cdev_open(struct inode *inode, struct file *file)
104 struct ubi_volume_desc *desc;
105 int vol_id = iminor(inode) - 1, mode, ubi_num;
107 ubi_num = ubi_major2num(imajor(inode));
111 if (file->f_mode & FMODE_WRITE)
112 mode = UBI_READWRITE;
116 dbg_gen("open device %d, volume %d, mode %d",
117 ubi_num, vol_id, mode);
119 desc = ubi_open_volume(ubi_num, vol_id, mode);
121 return PTR_ERR(desc);
123 file->private_data = desc;
127 static int vol_cdev_release(struct inode *inode, struct file *file)
129 struct ubi_volume_desc *desc = file->private_data;
130 struct ubi_volume *vol = desc->vol;
132 dbg_gen("release device %d, volume %d, mode %d",
133 vol->ubi->ubi_num, vol->vol_id, desc->mode);
136 ubi_warn("update of volume %d not finished, volume is damaged",
138 ubi_assert(!vol->changing_leb);
141 } else if (vol->changing_leb) {
142 dbg_gen("only %lld of %lld bytes received for atomic LEB change"
143 " for volume %d:%d, cancel", vol->upd_received,
144 vol->upd_bytes, vol->ubi->ubi_num, vol->vol_id);
145 vol->changing_leb = 0;
149 ubi_close_volume(desc);
153 static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin)
155 struct ubi_volume_desc *desc = file->private_data;
156 struct ubi_volume *vol = desc->vol;
160 /* Update is in progress, seeking is prohibited */
166 case 0: /* SEEK_SET */
169 case 1: /* SEEK_CUR */
170 new_offset = file->f_pos + offset;
172 case 2: /* SEEK_END */
173 new_offset = vol->used_bytes + offset;
179 if (new_offset < 0 || new_offset > vol->used_bytes) {
180 dbg_err("bad seek %lld", new_offset);
184 dbg_gen("seek volume %d, offset %lld, origin %d, new offset %lld",
185 vol->vol_id, offset, origin, new_offset);
187 file->f_pos = new_offset;
191 static int vol_cdev_fsync(struct file *file, struct dentry *dentry,
194 struct ubi_volume_desc *desc = file->private_data;
195 struct ubi_device *ubi = desc->vol->ubi;
197 return ubi_sync(ubi->ubi_num);
201 static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count,
204 struct ubi_volume_desc *desc = file->private_data;
205 struct ubi_volume *vol = desc->vol;
206 struct ubi_device *ubi = vol->ubi;
207 int err, lnum, off, len, tbuf_size;
208 size_t count_save = count;
211 dbg_gen("read %zd bytes from offset %lld of volume %d",
212 count, *offp, vol->vol_id);
218 if (vol->upd_marker) {
219 dbg_err("damaged volume, update marker is set");
222 if (*offp == vol->used_bytes || count == 0)
226 dbg_gen("read from corrupted volume %d", vol->vol_id);
228 if (*offp + count > vol->used_bytes)
229 count_save = count = vol->used_bytes - *offp;
231 tbuf_size = vol->usable_leb_size;
232 if (count < tbuf_size)
233 tbuf_size = ALIGN(count, ubi->min_io_size);
234 tbuf = vmalloc(tbuf_size);
238 len = count > tbuf_size ? tbuf_size : count;
239 lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
244 if (off + len >= vol->usable_leb_size)
245 len = vol->usable_leb_size - off;
247 err = ubi_eba_read_leb(ubi, vol, lnum, tbuf, off, len, 0);
252 if (off == vol->usable_leb_size) {
254 off -= vol->usable_leb_size;
260 err = copy_to_user(buf, tbuf, len);
267 len = count > tbuf_size ? tbuf_size : count;
271 return err ? err : count_save - count;
275 * This function allows to directly write to dynamic UBI volumes, without
276 * issuing the volume update operation.
278 static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf,
279 size_t count, loff_t *offp)
281 struct ubi_volume_desc *desc = file->private_data;
282 struct ubi_volume *vol = desc->vol;
283 struct ubi_device *ubi = vol->ubi;
284 int lnum, off, len, tbuf_size, err = 0;
285 size_t count_save = count;
288 if (!vol->direct_writes)
291 dbg_gen("requested: write %zd bytes to offset %lld of volume %u",
292 count, *offp, vol->vol_id);
294 if (vol->vol_type == UBI_STATIC_VOLUME)
297 lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
298 if (off & (ubi->min_io_size - 1)) {
299 dbg_err("unaligned position");
303 if (*offp + count > vol->used_bytes)
304 count_save = count = vol->used_bytes - *offp;
306 /* We can write only in fractions of the minimum I/O unit */
307 if (count & (ubi->min_io_size - 1)) {
308 dbg_err("unaligned write length");
312 tbuf_size = vol->usable_leb_size;
313 if (count < tbuf_size)
314 tbuf_size = ALIGN(count, ubi->min_io_size);
315 tbuf = vmalloc(tbuf_size);
319 len = count > tbuf_size ? tbuf_size : count;
324 if (off + len >= vol->usable_leb_size)
325 len = vol->usable_leb_size - off;
327 err = copy_from_user(tbuf, buf, len);
333 err = ubi_eba_write_leb(ubi, vol, lnum, tbuf, off, len,
339 if (off == vol->usable_leb_size) {
341 off -= vol->usable_leb_size;
347 len = count > tbuf_size ? tbuf_size : count;
351 return err ? err : count_save - count;
354 static ssize_t vol_cdev_write(struct file *file, const char __user *buf,
355 size_t count, loff_t *offp)
358 struct ubi_volume_desc *desc = file->private_data;
359 struct ubi_volume *vol = desc->vol;
360 struct ubi_device *ubi = vol->ubi;
362 if (!vol->updating && !vol->changing_leb)
363 return vol_cdev_direct_write(file, buf, count, offp);
366 err = ubi_more_update_data(ubi, vol, buf, count);
368 err = ubi_more_leb_change_data(ubi, vol, buf, count);
371 ubi_err("cannot accept more %zd bytes of data, error %d",
378 * The operation is finished, @err contains number of actually
383 if (vol->changing_leb) {
384 revoke_exclusive(desc, UBI_READWRITE);
388 err = ubi_check_volume(ubi, vol->vol_id);
393 ubi_warn("volume %d on UBI device %d is corrupted",
394 vol->vol_id, ubi->ubi_num);
398 ubi_gluebi_updated(vol);
399 ubi_volume_notify(ubi, vol, UBI_VOLUME_UPDATED);
400 revoke_exclusive(desc, UBI_READWRITE);
406 static long vol_cdev_ioctl(struct file *file, unsigned int cmd,
410 struct ubi_volume_desc *desc = file->private_data;
411 struct ubi_volume *vol = desc->vol;
412 struct ubi_device *ubi = vol->ubi;
413 void __user *argp = (void __user *)arg;
416 /* Volume update command */
419 int64_t bytes, rsvd_bytes;
421 if (!capable(CAP_SYS_RESOURCE)) {
426 err = copy_from_user(&bytes, argp, sizeof(int64_t));
432 if (desc->mode == UBI_READONLY) {
437 rsvd_bytes = (long long)vol->reserved_pebs *
438 ubi->leb_size-vol->data_pad;
439 if (bytes < 0 || bytes > rsvd_bytes) {
444 err = get_exclusive(desc);
448 err = ubi_start_update(ubi, vol, bytes);
450 revoke_exclusive(desc, UBI_READWRITE);
454 /* Atomic logical eraseblock change command */
457 struct ubi_leb_change_req req;
459 err = copy_from_user(&req, argp,
460 sizeof(struct ubi_leb_change_req));
466 if (desc->mode == UBI_READONLY ||
467 vol->vol_type == UBI_STATIC_VOLUME) {
472 /* Validate the request */
474 if (req.lnum < 0 || req.lnum >= vol->reserved_pebs ||
475 req.bytes < 0 || req.lnum >= vol->usable_leb_size)
477 if (req.dtype != UBI_LONGTERM && req.dtype != UBI_SHORTTERM &&
478 req.dtype != UBI_UNKNOWN)
481 err = get_exclusive(desc);
485 err = ubi_start_leb_change(ubi, vol, &req);
487 revoke_exclusive(desc, UBI_READWRITE);
491 /* Logical eraseblock erasure command */
496 err = get_user(lnum, (__user int32_t *)argp);
502 if (desc->mode == UBI_READONLY ||
503 vol->vol_type == UBI_STATIC_VOLUME) {
508 if (lnum < 0 || lnum >= vol->reserved_pebs) {
513 dbg_gen("erase LEB %d:%d", vol->vol_id, lnum);
514 err = ubi_eba_unmap_leb(ubi, vol, lnum);
518 err = ubi_wl_flush(ubi);
522 /* Logical eraseblock map command */
525 struct ubi_map_req req;
527 err = copy_from_user(&req, argp, sizeof(struct ubi_map_req));
532 err = ubi_leb_map(desc, req.lnum, req.dtype);
536 /* Logical eraseblock un-map command */
541 err = get_user(lnum, (__user int32_t *)argp);
546 err = ubi_leb_unmap(desc, lnum);
550 /* Check if logical eraseblock is mapped command */
555 err = get_user(lnum, (__user int32_t *)argp);
560 err = ubi_is_mapped(desc, lnum);
564 /* Set volume property command */
567 struct ubi_set_prop_req req;
569 err = copy_from_user(&req, argp,
570 sizeof(struct ubi_set_prop_req));
575 switch (req.property) {
576 case UBI_PROP_DIRECT_WRITE:
577 mutex_lock(&ubi->device_mutex);
578 desc->vol->direct_writes = !!req.value;
579 mutex_unlock(&ubi->device_mutex);
596 * verify_mkvol_req - verify volume creation request.
597 * @ubi: UBI device description object
598 * @req: the request to check
600 * This function zero if the request is correct, and %-EINVAL if not.
602 static int verify_mkvol_req(const struct ubi_device *ubi,
603 const struct ubi_mkvol_req *req)
605 int n, err = -EINVAL;
607 if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 ||
611 if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) &&
612 req->vol_id != UBI_VOL_NUM_AUTO)
615 if (req->alignment == 0)
621 if (req->vol_type != UBI_DYNAMIC_VOLUME &&
622 req->vol_type != UBI_STATIC_VOLUME)
625 if (req->alignment > ubi->leb_size)
628 n = req->alignment & (ubi->min_io_size - 1);
629 if (req->alignment != 1 && n)
632 if (req->name_len > UBI_VOL_NAME_MAX) {
637 n = strnlen(req->name, req->name_len + 1);
638 if (n != req->name_len)
644 dbg_err("bad volume creation request");
645 ubi_dbg_dump_mkvol_req(req);
650 * verify_rsvol_req - verify volume re-size request.
651 * @ubi: UBI device description object
652 * @req: the request to check
654 * This function returns zero if the request is correct, and %-EINVAL if not.
656 static int verify_rsvol_req(const struct ubi_device *ubi,
657 const struct ubi_rsvol_req *req)
662 if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots)
669 * rename_volumes - rename UBI volumes.
670 * @ubi: UBI device description object
671 * @req: volumes re-name request
673 * This is a helper function for the volume re-name IOCTL which validates the
674 * the request, opens the volume and calls corresponding volumes management
675 * function. Returns zero in case of success and a negative error code in case
678 static int rename_volumes(struct ubi_device *ubi,
679 struct ubi_rnvol_req *req)
682 struct list_head rename_list;
683 struct ubi_rename_entry *re, *re1;
685 if (req->count < 0 || req->count > UBI_MAX_RNVOL)
691 /* Validate volume IDs and names in the request */
692 for (i = 0; i < req->count; i++) {
693 if (req->ents[i].vol_id < 0 ||
694 req->ents[i].vol_id >= ubi->vtbl_slots)
696 if (req->ents[i].name_len < 0)
698 if (req->ents[i].name_len > UBI_VOL_NAME_MAX)
699 return -ENAMETOOLONG;
700 req->ents[i].name[req->ents[i].name_len] = '\0';
701 n = strlen(req->ents[i].name);
702 if (n != req->ents[i].name_len)
706 /* Make sure volume IDs and names are unique */
707 for (i = 0; i < req->count - 1; i++) {
708 for (n = i + 1; n < req->count; n++) {
709 if (req->ents[i].vol_id == req->ents[n].vol_id) {
710 dbg_err("duplicated volume id %d",
711 req->ents[i].vol_id);
714 if (!strcmp(req->ents[i].name, req->ents[n].name)) {
715 dbg_err("duplicated volume name \"%s\"",
722 /* Create the re-name list */
723 INIT_LIST_HEAD(&rename_list);
724 for (i = 0; i < req->count; i++) {
725 int vol_id = req->ents[i].vol_id;
726 int name_len = req->ents[i].name_len;
727 const char *name = req->ents[i].name;
729 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
735 re->desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
736 if (IS_ERR(re->desc)) {
737 err = PTR_ERR(re->desc);
738 dbg_err("cannot open volume %d, error %d", vol_id, err);
743 /* Skip this re-naming if the name does not really change */
744 if (re->desc->vol->name_len == name_len &&
745 !memcmp(re->desc->vol->name, name, name_len)) {
746 ubi_close_volume(re->desc);
751 re->new_name_len = name_len;
752 memcpy(re->new_name, name, name_len);
753 list_add_tail(&re->list, &rename_list);
754 dbg_msg("will rename volume %d from \"%s\" to \"%s\"",
755 vol_id, re->desc->vol->name, name);
758 if (list_empty(&rename_list))
761 /* Find out the volumes which have to be removed */
762 list_for_each_entry(re, &rename_list, list) {
763 struct ubi_volume_desc *desc;
764 int no_remove_needed = 0;
767 * Volume @re->vol_id is going to be re-named to
768 * @re->new_name, while its current name is @name. If a volume
769 * with name @re->new_name currently exists, it has to be
770 * removed, unless it is also re-named in the request (@req).
772 list_for_each_entry(re1, &rename_list, list) {
773 if (re->new_name_len == re1->desc->vol->name_len &&
774 !memcmp(re->new_name, re1->desc->vol->name,
775 re1->desc->vol->name_len)) {
776 no_remove_needed = 1;
781 if (no_remove_needed)
785 * It seems we need to remove volume with name @re->new_name,
788 desc = ubi_open_volume_nm(ubi->ubi_num, re->new_name,
793 /* Re-naming into a non-existing volume name */
796 /* The volume exists but busy, or an error occurred */
797 dbg_err("cannot open volume \"%s\", error %d",
802 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
805 ubi_close_volume(desc);
811 list_add(&re->list, &rename_list);
812 dbg_msg("will remove volume %d, name \"%s\"",
813 re->desc->vol->vol_id, re->desc->vol->name);
816 mutex_lock(&ubi->device_mutex);
817 err = ubi_rename_volumes(ubi, &rename_list);
818 mutex_unlock(&ubi->device_mutex);
821 list_for_each_entry_safe(re, re1, &rename_list, list) {
822 ubi_close_volume(re->desc);
829 static long ubi_cdev_ioctl(struct file *file, unsigned int cmd,
833 struct ubi_device *ubi;
834 struct ubi_volume_desc *desc;
835 void __user *argp = (void __user *)arg;
837 if (!capable(CAP_SYS_RESOURCE))
840 ubi = ubi_get_by_major(imajor(file->f_mapping->host));
845 /* Create volume command */
848 struct ubi_mkvol_req req;
850 dbg_gen("create volume");
851 err = copy_from_user(&req, argp, sizeof(struct ubi_mkvol_req));
857 req.name[req.name_len] = '\0';
858 err = verify_mkvol_req(ubi, &req);
862 mutex_lock(&ubi->device_mutex);
863 err = ubi_create_volume(ubi, &req);
864 mutex_unlock(&ubi->device_mutex);
868 err = put_user(req.vol_id, (__user int32_t *)argp);
875 /* Remove volume command */
880 dbg_gen("remove volume");
881 err = get_user(vol_id, (__user int32_t *)argp);
887 desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
893 mutex_lock(&ubi->device_mutex);
894 err = ubi_remove_volume(desc, 0);
895 mutex_unlock(&ubi->device_mutex);
898 * The volume is deleted (unless an error occurred), and the
899 * 'struct ubi_volume' object will be freed when
900 * 'ubi_close_volume()' will call 'put_device()'.
902 ubi_close_volume(desc);
906 /* Re-size volume command */
910 struct ubi_rsvol_req req;
912 dbg_gen("re-size volume");
913 err = copy_from_user(&req, argp, sizeof(struct ubi_rsvol_req));
919 err = verify_rsvol_req(ubi, &req);
923 desc = ubi_open_volume(ubi->ubi_num, req.vol_id, UBI_EXCLUSIVE);
929 pebs = div_u64(req.bytes + desc->vol->usable_leb_size - 1,
930 desc->vol->usable_leb_size);
932 mutex_lock(&ubi->device_mutex);
933 err = ubi_resize_volume(desc, pebs);
934 mutex_unlock(&ubi->device_mutex);
935 ubi_close_volume(desc);
939 /* Re-name volumes command */
942 struct ubi_rnvol_req *req;
944 dbg_msg("re-name volumes");
945 req = kmalloc(sizeof(struct ubi_rnvol_req), GFP_KERNEL);
951 err = copy_from_user(req, argp, sizeof(struct ubi_rnvol_req));
958 err = rename_volumes(ubi, req);
972 static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd,
976 void __user *argp = (void __user *)arg;
978 if (!capable(CAP_SYS_RESOURCE))
982 /* Attach an MTD device command */
985 struct ubi_attach_req req;
986 struct mtd_info *mtd;
988 dbg_gen("attach MTD device");
989 err = copy_from_user(&req, argp, sizeof(struct ubi_attach_req));
995 if (req.mtd_num < 0 ||
996 (req.ubi_num < 0 && req.ubi_num != UBI_DEV_NUM_AUTO)) {
1001 mtd = get_mtd_device(NULL, req.mtd_num);
1008 * Note, further request verification is done by
1009 * 'ubi_attach_mtd_dev()'.
1011 mutex_lock(&ubi_devices_mutex);
1012 err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset);
1013 mutex_unlock(&ubi_devices_mutex);
1015 put_mtd_device(mtd);
1017 /* @err contains UBI device number */
1018 err = put_user(err, (__user int32_t *)argp);
1023 /* Detach an MTD device command */
1028 dbg_gen("dettach MTD device");
1029 err = get_user(ubi_num, (__user int32_t *)argp);
1035 mutex_lock(&ubi_devices_mutex);
1036 err = ubi_detach_mtd_dev(ubi_num, 0);
1037 mutex_unlock(&ubi_devices_mutex);
1049 #ifdef CONFIG_COMPAT
1050 static long vol_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1053 unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1055 return vol_cdev_ioctl(file, cmd, translated_arg);
1058 static long ubi_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1061 unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1063 return ubi_cdev_ioctl(file, cmd, translated_arg);
1066 static long ctrl_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1069 unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1071 return ctrl_cdev_ioctl(file, cmd, translated_arg);
1074 #define vol_cdev_compat_ioctl NULL
1075 #define ubi_cdev_compat_ioctl NULL
1076 #define ctrl_cdev_compat_ioctl NULL
1079 /* UBI volume character device operations */
1080 const struct file_operations ubi_vol_cdev_operations = {
1081 .owner = THIS_MODULE,
1082 .open = vol_cdev_open,
1083 .release = vol_cdev_release,
1084 .llseek = vol_cdev_llseek,
1085 .read = vol_cdev_read,
1086 .write = vol_cdev_write,
1087 .fsync = vol_cdev_fsync,
1088 .unlocked_ioctl = vol_cdev_ioctl,
1089 .compat_ioctl = vol_cdev_compat_ioctl,
1092 /* UBI character device operations */
1093 const struct file_operations ubi_cdev_operations = {
1094 .owner = THIS_MODULE,
1095 .llseek = no_llseek,
1096 .unlocked_ioctl = ubi_cdev_ioctl,
1097 .compat_ioctl = ubi_cdev_compat_ioctl,
1100 /* UBI control character device operations */
1101 const struct file_operations ubi_ctrl_cdev_operations = {
1102 .owner = THIS_MODULE,
1103 .unlocked_ioctl = ctrl_cdev_ioctl,
1104 .compat_ioctl = ctrl_cdev_compat_ioctl,