1 /* 2 * Copyright (c) International Business Machines Corp., 2006 3 * 4 * SPDX-License-Identifier: GPL-2.0+ 5 * 6 * Author: Artem Bityutskiy (Битюцкий Артём) 7 */ 8 9 #ifndef __LINUX_UBI_H__ 10 #define __LINUX_UBI_H__ 11 12 #include <linux/types.h> 13 #ifndef __UBOOT__ 14 #include <linux/ioctl.h> 15 #include <mtd/ubi-user.h> 16 #endif 17 18 /* All voumes/LEBs */ 19 #define UBI_ALL -1 20 21 /* 22 * enum ubi_open_mode - UBI volume open mode constants. 23 * 24 * UBI_READONLY: read-only mode 25 * UBI_READWRITE: read-write mode 26 * UBI_EXCLUSIVE: exclusive mode 27 */ 28 enum { 29 UBI_READONLY = 1, 30 UBI_READWRITE, 31 UBI_EXCLUSIVE 32 }; 33 34 /** 35 * struct ubi_volume_info - UBI volume description data structure. 36 * @vol_id: volume ID 37 * @ubi_num: UBI device number this volume belongs to 38 * @size: how many physical eraseblocks are reserved for this volume 39 * @used_bytes: how many bytes of data this volume contains 40 * @used_ebs: how many physical eraseblocks of this volume actually contain any 41 * data 42 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME) 43 * @corrupted: non-zero if the volume is corrupted (static volumes only) 44 * @upd_marker: non-zero if the volume has update marker set 45 * @alignment: volume alignment 46 * @usable_leb_size: how many bytes are available in logical eraseblocks of 47 * this volume 48 * @name_len: volume name length 49 * @name: volume name 50 * @cdev: UBI volume character device major and minor numbers 51 * 52 * The @corrupted flag is only relevant to static volumes and is always zero 53 * for dynamic ones. This is because UBI does not care about dynamic volume 54 * data protection and only cares about protecting static volume data. 55 * 56 * The @upd_marker flag is set if the volume update operation was interrupted. 57 * Before touching the volume data during the update operation, UBI first sets 58 * the update marker flag for this volume. If the volume update operation was 59 * further interrupted, the update marker indicates this. If the update marker 60 * is set, the contents of the volume is certainly damaged and a new volume 61 * update operation has to be started. 62 * 63 * To put it differently, @corrupted and @upd_marker fields have different 64 * semantics: 65 * o the @corrupted flag means that this static volume is corrupted for some 66 * reasons, but not because an interrupted volume update 67 * o the @upd_marker field means that the volume is damaged because of an 68 * interrupted update operation. 69 * 70 * I.e., the @corrupted flag is never set if the @upd_marker flag is set. 71 * 72 * The @used_bytes and @used_ebs fields are only really needed for static 73 * volumes and contain the number of bytes stored in this static volume and how 74 * many eraseblock this data occupies. In case of dynamic volumes, the 75 * @used_bytes field is equivalent to @size*@usable_leb_size, and the @used_ebs 76 * field is equivalent to @size. 77 * 78 * In general, logical eraseblock size is a property of the UBI device, not 79 * of the UBI volume. Indeed, the logical eraseblock size depends on the 80 * physical eraseblock size and on how much bytes UBI headers consume. But 81 * because of the volume alignment (@alignment), the usable size of logical 82 * eraseblocks if a volume may be less. The following equation is true: 83 * @usable_leb_size = LEB size - (LEB size mod @alignment), 84 * where LEB size is the logical eraseblock size defined by the UBI device. 85 * 86 * The alignment is multiple to the minimal flash input/output unit size or %1 87 * if all the available space is used. 88 * 89 * To put this differently, alignment may be considered is a way to change 90 * volume logical eraseblock sizes. 91 */ 92 struct ubi_volume_info { 93 int ubi_num; 94 int vol_id; 95 int size; 96 long long used_bytes; 97 int used_ebs; 98 int vol_type; 99 int corrupted; 100 int upd_marker; 101 int alignment; 102 int usable_leb_size; 103 int name_len; 104 const char *name; 105 dev_t cdev; 106 }; 107 108 /** 109 * struct ubi_device_info - UBI device description data structure. 110 * @ubi_num: ubi device number 111 * @leb_size: logical eraseblock size on this UBI device 112 * @leb_start: starting offset of logical eraseblocks within physical 113 * eraseblocks 114 * @min_io_size: minimal I/O unit size 115 * @max_write_size: maximum amount of bytes the underlying flash can write at a 116 * time (MTD write buffer size) 117 * @ro_mode: if this device is in read-only mode 118 * @cdev: UBI character device major and minor numbers 119 * 120 * Note, @leb_size is the logical eraseblock size offered by the UBI device. 121 * Volumes of this UBI device may have smaller logical eraseblock size if their 122 * alignment is not equivalent to %1. 123 * 124 * The @max_write_size field describes flash write maximum write unit. For 125 * example, NOR flash allows for changing individual bytes, so @min_io_size is 126 * %1. However, it does not mean than NOR flash has to write data byte-by-byte. 127 * Instead, CFI NOR flashes have a write-buffer of, e.g., 64 bytes, and when 128 * writing large chunks of data, they write 64-bytes at a time. Obviously, this 129 * improves write throughput. 130 * 131 * Also, the MTD device may have N interleaved (striped) flash chips 132 * underneath, in which case @min_io_size can be physical min. I/O size of 133 * single flash chip, while @max_write_size can be N * @min_io_size. 134 * 135 * The @max_write_size field is always greater or equivalent to @min_io_size. 136 * E.g., some NOR flashes may have (@min_io_size = 1, @max_write_size = 64). In 137 * contrast, NAND flashes usually have @min_io_size = @max_write_size = NAND 138 * page size. 139 */ 140 struct ubi_device_info { 141 int ubi_num; 142 int leb_size; 143 int leb_start; 144 int min_io_size; 145 int max_write_size; 146 int ro_mode; 147 #ifndef __UBOOT__ 148 dev_t cdev; 149 #endif 150 }; 151 152 /* 153 * Volume notification types. 154 * @UBI_VOLUME_ADDED: a volume has been added (an UBI device was attached or a 155 * volume was created) 156 * @UBI_VOLUME_REMOVED: a volume has been removed (an UBI device was detached 157 * or a volume was removed) 158 * @UBI_VOLUME_RESIZED: a volume has been re-sized 159 * @UBI_VOLUME_RENAMED: a volume has been re-named 160 * @UBI_VOLUME_UPDATED: data has been written to a volume 161 * 162 * These constants define which type of event has happened when a volume 163 * notification function is invoked. 164 */ 165 enum { 166 UBI_VOLUME_ADDED, 167 UBI_VOLUME_REMOVED, 168 UBI_VOLUME_RESIZED, 169 UBI_VOLUME_RENAMED, 170 UBI_VOLUME_UPDATED, 171 }; 172 173 /* 174 * struct ubi_notification - UBI notification description structure. 175 * @di: UBI device description object 176 * @vi: UBI volume description object 177 * 178 * UBI notifiers are called with a pointer to an object of this type. The 179 * object describes the notification. Namely, it provides a description of the 180 * UBI device and UBI volume the notification informs about. 181 */ 182 struct ubi_notification { 183 struct ubi_device_info di; 184 struct ubi_volume_info vi; 185 }; 186 187 /* UBI descriptor given to users when they open UBI volumes */ 188 struct ubi_volume_desc; 189 190 int ubi_get_device_info(int ubi_num, struct ubi_device_info *di); 191 void ubi_get_volume_info(struct ubi_volume_desc *desc, 192 struct ubi_volume_info *vi); 193 struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode); 194 struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, 195 int mode); 196 struct ubi_volume_desc *ubi_open_volume_path(const char *pathname, int mode); 197 198 #ifndef __UBOOT__ 199 typedef int (*notifier_fn_t)(void *nb, 200 unsigned long action, void *data); 201 202 struct notifier_block { 203 notifier_fn_t notifier_call; 204 struct notifier_block *next; 205 void *next; 206 int priority; 207 }; 208 209 int ubi_register_volume_notifier(struct notifier_block *nb, 210 int ignore_existing); 211 int ubi_unregister_volume_notifier(struct notifier_block *nb); 212 #endif 213 214 void ubi_close_volume(struct ubi_volume_desc *desc); 215 int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, 216 int len, int check); 217 int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, 218 int offset, int len); 219 int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, 220 int len); 221 int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum); 222 int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum); 223 int ubi_leb_map(struct ubi_volume_desc *desc, int lnum); 224 int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum); 225 int ubi_sync(int ubi_num); 226 int ubi_flush(int ubi_num, int vol_id, int lnum); 227 228 /* 229 * This function is the same as the 'ubi_leb_read()' function, but it does not 230 * provide the checking capability. 231 */ 232 static inline int ubi_read(struct ubi_volume_desc *desc, int lnum, char *buf, 233 int offset, int len) 234 { 235 return ubi_leb_read(desc, lnum, buf, offset, len, 0); 236 } 237 #endif /* !__LINUX_UBI_H__ */ 238