1 /* 2 * Copyright (c) International Business Machines Corp., 2006 3 * 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. 8 * 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. 13 * 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 17 * 18 * Author: Artem Bityutskiy (Битюцкий Артём) 19 */ 20 21 #ifndef __LINUX_UBI_H__ 22 #define __LINUX_UBI_H__ 23 24 #include <linux/ioctl.h> 25 #include <linux/types.h> 26 #include <mtd/ubi-user.h> 27 28 /* All voumes/LEBs */ 29 #define UBI_ALL -1 30 31 /* 32 * enum ubi_open_mode - UBI volume open mode constants. 33 * 34 * UBI_READONLY: read-only mode 35 * UBI_READWRITE: read-write mode 36 * UBI_EXCLUSIVE: exclusive mode 37 */ 38 enum { 39 UBI_READONLY = 1, 40 UBI_READWRITE, 41 UBI_EXCLUSIVE 42 }; 43 44 /** 45 * struct ubi_volume_info - UBI volume description data structure. 46 * @vol_id: volume ID 47 * @ubi_num: UBI device number this volume belongs to 48 * @size: how many physical eraseblocks are reserved for this volume 49 * @used_bytes: how many bytes of data this volume contains 50 * @used_ebs: how many physical eraseblocks of this volume actually contain any 51 * data 52 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME) 53 * @corrupted: non-zero if the volume is corrupted (static volumes only) 54 * @upd_marker: non-zero if the volume has update marker set 55 * @alignment: volume alignment 56 * @usable_leb_size: how many bytes are available in logical eraseblocks of 57 * this volume 58 * @name_len: volume name length 59 * @name: volume name 60 * @cdev: UBI volume character device major and minor numbers 61 * 62 * The @corrupted flag is only relevant to static volumes and is always zero 63 * for dynamic ones. This is because UBI does not care about dynamic volume 64 * data protection and only cares about protecting static volume data. 65 * 66 * The @upd_marker flag is set if the volume update operation was interrupted. 67 * Before touching the volume data during the update operation, UBI first sets 68 * the update marker flag for this volume. If the volume update operation was 69 * further interrupted, the update marker indicates this. If the update marker 70 * is set, the contents of the volume is certainly damaged and a new volume 71 * update operation has to be started. 72 * 73 * To put it differently, @corrupted and @upd_marker fields have different 74 * semantics: 75 * o the @corrupted flag means that this static volume is corrupted for some 76 * reasons, but not because an interrupted volume update 77 * o the @upd_marker field means that the volume is damaged because of an 78 * interrupted update operation. 79 * 80 * I.e., the @corrupted flag is never set if the @upd_marker flag is set. 81 * 82 * The @used_bytes and @used_ebs fields are only really needed for static 83 * volumes and contain the number of bytes stored in this static volume and how 84 * many eraseblock this data occupies. In case of dynamic volumes, the 85 * @used_bytes field is equivalent to @size*@usable_leb_size, and the @used_ebs 86 * field is equivalent to @size. 87 * 88 * In general, logical eraseblock size is a property of the UBI device, not 89 * of the UBI volume. Indeed, the logical eraseblock size depends on the 90 * physical eraseblock size and on how much bytes UBI headers consume. But 91 * because of the volume alignment (@alignment), the usable size of logical 92 * eraseblocks if a volume may be less. The following equation is true: 93 * @usable_leb_size = LEB size - (LEB size mod @alignment), 94 * where LEB size is the logical eraseblock size defined by the UBI device. 95 * 96 * The alignment is multiple to the minimal flash input/output unit size or %1 97 * if all the available space is used. 98 * 99 * To put this differently, alignment may be considered is a way to change 100 * volume logical eraseblock sizes. 101 */ 102 struct ubi_volume_info { 103 int ubi_num; 104 int vol_id; 105 int size; 106 long long used_bytes; 107 int used_ebs; 108 int vol_type; 109 int corrupted; 110 int upd_marker; 111 int alignment; 112 int usable_leb_size; 113 int name_len; 114 const char *name; 115 dev_t cdev; 116 }; 117 118 /** 119 * struct ubi_device_info - UBI device description data structure. 120 * @ubi_num: ubi device number 121 * @leb_size: logical eraseblock size on this UBI device 122 * @leb_start: starting offset of logical eraseblocks within physical 123 * eraseblocks 124 * @min_io_size: minimal I/O unit size 125 * @max_write_size: maximum amount of bytes the underlying flash can write at a 126 * time (MTD write buffer size) 127 * @ro_mode: if this device is in read-only mode 128 * @cdev: UBI character device major and minor numbers 129 * 130 * Note, @leb_size is the logical eraseblock size offered by the UBI device. 131 * Volumes of this UBI device may have smaller logical eraseblock size if their 132 * alignment is not equivalent to %1. 133 * 134 * The @max_write_size field describes flash write maximum write unit. For 135 * example, NOR flash allows for changing individual bytes, so @min_io_size is 136 * %1. However, it does not mean than NOR flash has to write data byte-by-byte. 137 * Instead, CFI NOR flashes have a write-buffer of, e.g., 64 bytes, and when 138 * writing large chunks of data, they write 64-bytes at a time. Obviously, this 139 * improves write throughput. 140 * 141 * Also, the MTD device may have N interleaved (striped) flash chips 142 * underneath, in which case @min_io_size can be physical min. I/O size of 143 * single flash chip, while @max_write_size can be N * @min_io_size. 144 * 145 * The @max_write_size field is always greater or equivalent to @min_io_size. 146 * E.g., some NOR flashes may have (@min_io_size = 1, @max_write_size = 64). In 147 * contrast, NAND flashes usually have @min_io_size = @max_write_size = NAND 148 * page size. 149 */ 150 struct ubi_device_info { 151 int ubi_num; 152 int leb_size; 153 int leb_start; 154 int min_io_size; 155 int max_write_size; 156 int ro_mode; 157 dev_t cdev; 158 }; 159 160 /* 161 * Volume notification types. 162 * @UBI_VOLUME_ADDED: a volume has been added (an UBI device was attached or a 163 * volume was created) 164 * @UBI_VOLUME_REMOVED: a volume has been removed (an UBI device was detached 165 * or a volume was removed) 166 * @UBI_VOLUME_RESIZED: a volume has been re-sized 167 * @UBI_VOLUME_RENAMED: a volume has been re-named 168 * @UBI_VOLUME_UPDATED: data has been written to a volume 169 * 170 * These constants define which type of event has happened when a volume 171 * notification function is invoked. 172 */ 173 enum { 174 UBI_VOLUME_ADDED, 175 UBI_VOLUME_REMOVED, 176 UBI_VOLUME_RESIZED, 177 UBI_VOLUME_RENAMED, 178 UBI_VOLUME_UPDATED, 179 }; 180 181 /* 182 * struct ubi_notification - UBI notification description structure. 183 * @di: UBI device description object 184 * @vi: UBI volume description object 185 * 186 * UBI notifiers are called with a pointer to an object of this type. The 187 * object describes the notification. Namely, it provides a description of the 188 * UBI device and UBI volume the notification informs about. 189 */ 190 struct ubi_notification { 191 struct ubi_device_info di; 192 struct ubi_volume_info vi; 193 }; 194 195 /* UBI descriptor given to users when they open UBI volumes */ 196 struct ubi_volume_desc; 197 198 int ubi_get_device_info(int ubi_num, struct ubi_device_info *di); 199 void ubi_get_volume_info(struct ubi_volume_desc *desc, 200 struct ubi_volume_info *vi); 201 struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode); 202 struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, 203 int mode); 204 struct ubi_volume_desc *ubi_open_volume_path(const char *pathname, int mode); 205 206 int ubi_register_volume_notifier(struct notifier_block *nb, 207 int ignore_existing); 208 int ubi_unregister_volume_notifier(struct notifier_block *nb); 209 210 void ubi_close_volume(struct ubi_volume_desc *desc); 211 int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, 212 int len, int check); 213 int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, 214 int offset, int len); 215 int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, 216 int len); 217 int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum); 218 int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum); 219 int ubi_leb_map(struct ubi_volume_desc *desc, int lnum); 220 int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum); 221 int ubi_sync(int ubi_num); 222 int ubi_flush(int ubi_num, int vol_id, int lnum); 223 224 /* 225 * This function is the same as the 'ubi_leb_read()' function, but it does not 226 * provide the checking capability. 227 */ 228 static inline int ubi_read(struct ubi_volume_desc *desc, int lnum, char *buf, 229 int offset, int len) 230 { 231 return ubi_leb_read(desc, lnum, buf, offset, len, 0); 232 } 233 #endif /* !__LINUX_UBI_H__ */ 234