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Diffstat (limited to 'fs/ubifs/ubifs.h')
| -rw-r--r-- | fs/ubifs/ubifs.h | 1649 |
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diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h new file mode 100644 index 00000000000..e4f89f27182 --- /dev/null +++ b/fs/ubifs/ubifs.h @@ -0,0 +1,1649 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* Implementation version 0.7 */ + +#ifndef __UBIFS_H__ +#define __UBIFS_H__ + +#include <asm/div64.h> +#include <linux/statfs.h> +#include <linux/fs.h> +#include <linux/err.h> +#include <linux/sched.h> +#include <linux/vmalloc.h> +#include <linux/spinlock.h> +#include <linux/mutex.h> +#include <linux/rwsem.h> +#include <linux/mtd/ubi.h> +#include <linux/pagemap.h> +#include <linux/backing-dev.h> +#include "ubifs-media.h" + +/* Version of this UBIFS implementation */ +#define UBIFS_VERSION 1 + +/* Normal UBIFS messages */ +#define ubifs_msg(fmt, ...) \ + printk(KERN_NOTICE "UBIFS: " fmt "\n", ##__VA_ARGS__) +/* UBIFS error messages */ +#define ubifs_err(fmt, ...) \ + printk(KERN_ERR "UBIFS error (pid %d): %s: " fmt "\n", current->pid, \ + __func__, ##__VA_ARGS__) +/* UBIFS warning messages */ +#define ubifs_warn(fmt, ...) \ + printk(KERN_WARNING "UBIFS warning (pid %d): %s: " fmt "\n", \ + current->pid, __func__, ##__VA_ARGS__) + +/* UBIFS file system VFS magic number */ +#define UBIFS_SUPER_MAGIC 0x24051905 + +/* Number of UBIFS blocks per VFS page */ +#define UBIFS_BLOCKS_PER_PAGE (PAGE_CACHE_SIZE / UBIFS_BLOCK_SIZE) +#define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_CACHE_SHIFT - UBIFS_BLOCK_SHIFT) + +/* "File system end of life" sequence number watermark */ +#define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL +#define SQNUM_WATERMARK 0xFFFFFFFFFF000000ULL + +/* Minimum amount of data UBIFS writes to the flash */ +#define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8) + +/* + * Currently we do not support inode number overlapping and re-using, so this + * watermark defines dangerous inode number level. This should be fixed later, + * although it is difficult to exceed current limit. Another option is to use + * 64-bit inode numbers, but this means more overhead. + */ +#define INUM_WARN_WATERMARK 0xFFF00000 +#define INUM_WATERMARK 0xFFFFFF00 + +/* Largest key size supported in this implementation */ +#define CUR_MAX_KEY_LEN UBIFS_SK_LEN + +/* Maximum number of entries in each LPT (LEB category) heap */ +#define LPT_HEAP_SZ 256 + +/* + * Background thread name pattern. The numbers are UBI device and volume + * numbers. + */ +#define BGT_NAME_PATTERN "ubifs_bgt%d_%d" + +/* Default write-buffer synchronization timeout (5 secs) */ +#define DEFAULT_WBUF_TIMEOUT (5 * HZ) + +/* Maximum possible inode number (only 32-bit inodes are supported now) */ +#define MAX_INUM 0xFFFFFFFF + +/* Number of non-data journal heads */ +#define NONDATA_JHEADS_CNT 2 + +/* Garbage collector head */ +#define GCHD 0 +/* Base journal head number */ +#define BASEHD 1 +/* First "general purpose" journal head */ +#define DATAHD 2 + +/* 'No change' value for 'ubifs_change_lp()' */ +#define LPROPS_NC 0x80000001 + +/* + * There is no notion of truncation key because truncation nodes do not exist + * in TNC. However, when replaying, it is handy to introduce fake "truncation" + * keys for truncation nodes because the code becomes simpler. So we define + * %UBIFS_TRUN_KEY type. + */ +#define UBIFS_TRUN_KEY UBIFS_KEY_TYPES_CNT + +/* + * How much a directory entry/extended attribute entry adds to the parent/host + * inode. + */ +#define CALC_DENT_SIZE(name_len) ALIGN(UBIFS_DENT_NODE_SZ + (name_len) + 1, 8) + +/* How much an extended attribute adds to the host inode */ +#define CALC_XATTR_BYTES(data_len) ALIGN(UBIFS_INO_NODE_SZ + (data_len) + 1, 8) + +/* + * Znodes which were not touched for 'OLD_ZNODE_AGE' seconds are considered + * "old", and znode which were touched last 'YOUNG_ZNODE_AGE' seconds ago are + * considered "young". This is used by shrinker when selecting znode to trim + * off. + */ +#define OLD_ZNODE_AGE 20 +#define YOUNG_ZNODE_AGE 5 + +/* + * Some compressors, like LZO, may end up with more data then the input buffer. + * So UBIFS always allocates larger output buffer, to be sure the compressor + * will not corrupt memory in case of worst case compression. + */ +#define WORST_COMPR_FACTOR 2 + +/* Maximum expected tree height for use by bottom_up_buf */ +#define BOTTOM_UP_HEIGHT 64 + +/* + * Lockdep classes for UBIFS inode @ui_mutex. + */ +enum { + WB_MUTEX_1 = 0, + WB_MUTEX_2 = 1, + WB_MUTEX_3 = 2, +}; + +/* + * Znode flags (actually, bit numbers which store the flags). + * + * DIRTY_ZNODE: znode is dirty + * COW_ZNODE: znode is being committed and a new instance of this znode has to + * be created before changing this znode + * OBSOLETE_ZNODE: znode is obsolete, which means it was deleted, but it is + * still in the commit list and the ongoing commit operation + * will commit it, and delete this znode after it is done + */ +enum { + DIRTY_ZNODE = 0, + COW_ZNODE = 1, + OBSOLETE_ZNODE = 2, +}; + +/* + * Commit states. + * + * COMMIT_RESTING: commit is not wanted + * COMMIT_BACKGROUND: background commit has been requested + * COMMIT_REQUIRED: commit is required + * COMMIT_RUNNING_BACKGROUND: background commit is running + * COMMIT_RUNNING_REQUIRED: commit is running and it is required + * COMMIT_BROKEN: commit failed + */ +enum { + COMMIT_RESTING = 0, + COMMIT_BACKGROUND, + COMMIT_REQUIRED, + COMMIT_RUNNING_BACKGROUND, + COMMIT_RUNNING_REQUIRED, + COMMIT_BROKEN, +}; + +/* + * 'ubifs_scan_a_node()' return values. + * + * SCANNED_GARBAGE: scanned garbage + * SCANNED_EMPTY_SPACE: scanned empty space + * SCANNED_A_NODE: scanned a valid node + * SCANNED_A_CORRUPT_NODE: scanned a corrupted node + * SCANNED_A_BAD_PAD_NODE: scanned a padding node with invalid pad length + * + * Greater than zero means: 'scanned that number of padding bytes' + */ +enum { + SCANNED_GARBAGE = 0, + SCANNED_EMPTY_SPACE = -1, + SCANNED_A_NODE = -2, + SCANNED_A_CORRUPT_NODE = -3, + SCANNED_A_BAD_PAD_NODE = -4, +}; + +/* + * LPT cnode flag bits. + * + * DIRTY_CNODE: cnode is dirty + * COW_CNODE: cnode is being committed and must be copied before writing + * OBSOLETE_CNODE: cnode is being committed and has been copied (or deleted), + * so it can (and must) be freed when the commit is finished + */ +enum { + DIRTY_CNODE = 0, + COW_CNODE = 1, + OBSOLETE_CNODE = 2, +}; + +/* + * Dirty flag bits (lpt_drty_flgs) for LPT special nodes. + * + * LTAB_DIRTY: ltab node is dirty + * LSAVE_DIRTY: lsave node is dirty + */ +enum { + LTAB_DIRTY = 1, + LSAVE_DIRTY = 2, +}; + +/* + * Return codes used by the garbage collector. + * @LEB_FREED: the logical eraseblock was freed and is ready to use + * @LEB_FREED_IDX: indexing LEB was freed and can be used only after the commit + * @LEB_RETAINED: the logical eraseblock was freed and retained for GC purposes + */ +enum { + LEB_FREED, + LEB_FREED_IDX, + LEB_RETAINED, +}; + +/** + * struct ubifs_old_idx - index node obsoleted since last commit start. + * @rb: rb-tree node + * @lnum: LEB number of obsoleted index node + * @offs: offset of obsoleted index node + */ +struct ubifs_old_idx { + struct rb_node rb; + int lnum; + int offs; +}; + +/* The below union makes it easier to deal with keys */ +union ubifs_key { + uint8_t u8[CUR_MAX_KEY_LEN]; + uint32_t u32[CUR_MAX_KEY_LEN/4]; + uint64_t u64[CUR_MAX_KEY_LEN/8]; + __le32 j32[CUR_MAX_KEY_LEN/4]; +}; + +/** + * struct ubifs_scan_node - UBIFS scanned node information. + * @list: list of scanned nodes + * @key: key of node scanned (if it has one) + * @sqnum: sequence number + * @type: type of node scanned + * @offs: offset with LEB of node scanned + * @len: length of node scanned + * @node: raw node + */ +struct ubifs_scan_node { + struct list_head list; + union ubifs_key key; + unsigned long long sqnum; + int type; + int offs; + int len; + void *node; +}; + +/** + * struct ubifs_scan_leb - UBIFS scanned LEB information. + * @lnum: logical eraseblock number + * @nodes_cnt: number of nodes scanned + * @nodes: list of struct ubifs_scan_node + * @endpt: end point (and therefore the start of empty space) + * @ecc: read returned -EBADMSG + * @buf: buffer containing entire LEB scanned + */ +struct ubifs_scan_leb { + int lnum; + int nodes_cnt; + struct list_head nodes; + int endpt; + int ecc; + void *buf; +}; + +/** + * struct ubifs_gced_idx_leb - garbage-collected indexing LEB. + * @list: list + * @lnum: LEB number + * @unmap: OK to unmap this LEB + * + * This data structure is used to temporary store garbage-collected indexing + * LEBs - they are not released immediately, but only after the next commit. + * This is needed to guarantee recoverability. + */ +struct ubifs_gced_idx_leb { + struct list_head list; + int lnum; + int unmap; +}; + +/** + * struct ubifs_inode - UBIFS in-memory inode description. + * @vfs_inode: VFS inode description object + * @creat_sqnum: sequence number at time of creation + * @xattr_size: summarized size of all extended attributes in bytes + * @xattr_cnt: count of extended attributes this inode has + * @xattr_names: sum of lengths of all extended attribute names belonging to + * this inode + * @dirty: non-zero if the inode is dirty + * @xattr: non-zero if this is an extended attribute inode + * @ui_mutex: serializes inode write-back with the rest of VFS operations, + * serializes "clean <-> dirty" state changes, protects @dirty, + * @ui_size, and @xattr_size + * @ui_lock: protects @synced_i_size + * @synced_i_size: synchronized size of inode, i.e. the value of inode size + * currently stored on the flash; used only for regular file + * inodes + * @ui_size: inode size used by UBIFS when writing to flash + * @flags: inode flags (@UBIFS_COMPR_FL, etc) + * @compr_type: default compression type used for this inode + * @data_len: length of the data attached to the inode + * @data: inode's data + * + * @ui_mutex exists for two main reasons. At first it prevents inodes from + * being written back while UBIFS changing them, being in the middle of an VFS + * operation. This way UBIFS makes sure the inode fields are consistent. For + * example, in 'ubifs_rename()' we change 3 inodes simultaneously, and + * write-back must not write any of them before we have finished. + * + * The second reason is budgeting - UBIFS has to budget all operations. If an + * operation is going to mark an inode dirty, it has to allocate budget for + * this. It cannot just mark it dirty because there is no guarantee there will + * be enough flash space to write the inode back later. This means UBIFS has + * to have full control over inode "clean <-> dirty" transitions (and pages + * actually). But unfortunately, VFS marks inodes dirty in many places, and it + * does not ask the file-system if it is allowed to do so (there is a notifier, + * but it is not enough), i.e., there is no mechanism to synchronize with this. + * So UBIFS has its own inode dirty flag and its own mutex to serialize + * "clean <-> dirty" transitions. + * + * The @synced_i_size field is used to make sure we never write pages which are + * beyond last synchronized inode size. See 'ubifs_writepage()' for more + * information. + * + * The @ui_size is a "shadow" variable for @inode->i_size and UBIFS uses + * @ui_size instead of @inode->i_size. The reason for this is that UBIFS cannot + * make sure @inode->i_size is always changed under @ui_mutex, because it + * cannot call 'vmtruncate()' with @ui_mutex locked, because it would deadlock + * with 'ubifs_writepage()' (see file.c). All the other inode fields are + * changed under @ui_mutex, so they do not need "shadow" fields. Note, one + * could consider to rework locking and base it on "shadow" fields. + */ +struct ubifs_inode { + struct inode vfs_inode; + unsigned long long creat_sqnum; + unsigned int xattr_size; + unsigned int xattr_cnt; + unsigned int xattr_names; + unsigned int dirty:1; + unsigned int xattr:1; + struct mutex ui_mutex; + spinlock_t ui_lock; + loff_t synced_i_size; + loff_t ui_size; + int flags; + int compr_type; + int data_len; + void *data; +}; + +/** + * struct ubifs_unclean_leb - records a LEB recovered under read-only mode. + * @list: list + * @lnum: LEB number of recovered LEB + * @endpt: offset where recovery ended + * + * This structure records a LEB identified during recovery that needs to be + * cleaned but was not because UBIFS was mounted read-only. The information + * is used to clean the LEB when remounting to read-write mode. + */ +struct ubifs_unclean_leb { + struct list_head list; + int lnum; + int endpt; +}; + +/* + * LEB properties flags. + * + * LPROPS_UNCAT: not categorized + * LPROPS_DIRTY: dirty > 0, not index + * LPROPS_DIRTY_IDX: dirty + free > UBIFS_CH_SZ and index + * LPROPS_FREE: free > 0, not empty, not index + * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs + * LPROPS_EMPTY: LEB is empty, not taken + * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken + * LPROPS_FRDI_IDX: free + dirty == leb_size and index, may be taken + * LPROPS_CAT_MASK: mask for the LEB categories above + * LPROPS_TAKEN: LEB was taken (this flag is not saved on the media) + * LPROPS_INDEX: LEB contains indexing nodes (this flag also exists on flash) + */ +enum { + LPROPS_UNCAT = 0, + LPROPS_DIRTY = 1, + LPROPS_DIRTY_IDX = 2, + LPROPS_FREE = 3, + LPROPS_HEAP_CNT = 3, + LPROPS_EMPTY = 4, + LPROPS_FREEABLE = 5, + LPROPS_FRDI_IDX = 6, + LPROPS_CAT_MASK = 15, + LPROPS_TAKEN = 16, + LPROPS_INDEX = 32, +}; + +/** + * struct ubifs_lprops - logical eraseblock properties. + * @free: amount of free space in bytes + * @dirty: amount of dirty space in bytes + * @flags: LEB properties flags (see above) + * @lnum: LEB number + * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE) + * @hpos: heap position in heap of same-category lprops (other categories) + */ +struct ubifs_lprops { + int free; + int dirty; + int flags; + int lnum; + union { + struct list_head list; + int hpos; + }; +}; + +/** + * struct ubifs_lpt_lprops - LPT logical eraseblock properties. + * @free: amount of free space in bytes + * @dirty: amount of dirty space in bytes + * @tgc: trivial GC flag (1 => unmap after commit end) + * @cmt: commit flag (1 => reserved for commit) + */ +struct ubifs_lpt_lprops { + int free; + int dirty; + unsigned tgc : 1; + unsigned cmt : 1; +}; + +/** + * struct ubifs_lp_stats - statistics of eraseblocks in the main area. + * @empty_lebs: number of empty LEBs + * @taken_empty_lebs: number of taken LEBs + * @idx_lebs: number of indexing LEBs + * @total_free: total free space in bytes + * @total_dirty: total dirty space in bytes + * @total_used: total used space in bytes (includes only data LEBs) + * @total_dead: total dead space in bytes (includes only data LEBs) + * @total_dark: total dark space in bytes (includes only data LEBs) + * + * N.B. total_dirty and total_used are different to other total_* fields, + * because they account _all_ LEBs, not just data LEBs. + * + * 'taken_empty_lebs' counts the LEBs that are in the transient state of having + * been 'taken' for use but not yet written to. 'taken_empty_lebs' is needed + * to account correctly for gc_lnum, otherwise 'empty_lebs' could be used + * by itself (in which case 'unused_lebs' would be a better name). In the case + * of gc_lnum, it is 'taken' at mount time or whenever a LEB is retained by GC, + * but unlike other empty LEBs that are 'taken', it may not be written straight + * away (i.e. before the next commit start or unmount), so either gc_lnum must + * be specially accounted for, or the current approach followed i.e. count it + * under 'taken_empty_lebs'. + */ +struct ubifs_lp_stats { + int empty_lebs; + int taken_empty_lebs; + int idx_lebs; + long long total_free; + long long total_dirty; + long long total_used; + long long total_dead; + long long total_dark; +}; + +struct ubifs_nnode; + +/** + * struct ubifs_cnode - LEB Properties Tree common node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (zero for pnodes, greater than zero for nnodes) + * @num: node number + */ +struct ubifs_cnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; +}; + +/** + * struct ubifs_pnode - LEB Properties Tree leaf node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (always zero for pnodes) + * @num: node number + * @lprops: LEB properties array + */ +struct ubifs_pnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; + struct ubifs_lprops lprops[UBIFS_LPT_FANOUT]; +}; + +/** + * struct ubifs_nbranch - LEB Properties Tree internal node branch. + * @lnum: LEB number of child + * @offs: offset of child + * @nnode: nnode child + * @pnode: pnode child + * @cnode: cnode child + */ +struct ubifs_nbranch { + int lnum; + int offs; + union { + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + struct ubifs_cnode *cnode; + }; +}; + +/** + * struct ubifs_nnode - LEB Properties Tree internal node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (always greater than zero for nnodes) + * @num: node number + * @nbranch: branches to child nodes + */ +struct ubifs_nnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; + struct ubifs_nbranch nbranch[UBIFS_LPT_FANOUT]; +}; + +/** + * struct ubifs_lpt_heap - heap of categorized lprops. + * @arr: heap array + * @cnt: number in heap + * @max_cnt: maximum number allowed in heap + * + * There are %LPROPS_HEAP_CNT heaps. + */ +struct ubifs_lpt_heap { + struct ubifs_lprops **arr; + int cnt; + int max_cnt; +}; + +/* + * Return codes for LPT scan callback function. + * + * LPT_SCAN_CONTINUE: continue scanning + * LPT_SCAN_ADD: add the LEB properties scanned to the tree in memory + * LPT_SCAN_STOP: stop scanning + */ +enum { + LPT_SCAN_CONTINUE = 0, + LPT_SCAN_ADD = 1, + LPT_SCAN_STOP = 2, +}; + +struct ubifs_info; + +/* Callback used by the 'ubifs_lpt_scan_nolock()' function */ +typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c, + const struct ubifs_lprops *lprops, + int in_tree, void *data); + +/** + * struct ubifs_wbuf - UBIFS write-buffer. + * @c: UBIFS file-system description object + * @buf: write-buffer (of min. flash I/O unit size) + * @lnum: logical eraseblock number the write-buffer points to + * @offs: write-buffer offset in this logical eraseblock + * @avail: number of bytes available in the write-buffer + * @used: number of used bytes in the write-buffer + * @dtype: type of data stored in this LEB (%UBI_LONGTERM, %UBI_SHORTTERM, + * %UBI_UNKNOWN) + * @jhead: journal head the mutex belongs to (note, needed only to shut lockdep + * up by 'mutex_lock_nested()). + * @sync_callback: write-buffer synchronization callback + * @io_mutex: serializes write-buffer I/O + * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes + * fields + * @timer: write-buffer timer + * @timeout: timer expire interval in jiffies + * @need_sync: it is set if its timer expired and needs sync + * @next_ino: points to the next position of the following inode number + * @inodes: stores the inode numbers of the nodes which are in wbuf + * + * The write-buffer synchronization callback is called when the write-buffer is + * synchronized in order to notify how much space was wasted due to + * write-buffer padding and how much free space is left in the LEB. + * + * Note: the fields @buf, @lnum, @offs, @avail and @used can be read under + * spin-lock or mutex because they are written under both mutex and spin-lock. + * @buf is appended to under mutex but overwritten under both mutex and + * spin-lock. Thus the data between @buf and @buf + @used can be read under + * spinlock. + */ +struct ubifs_wbuf { + struct ubifs_info *c; + void *buf; + int lnum; + int offs; + int avail; + int used; + int dtype; + int jhead; + int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad); + struct mutex io_mutex; + spinlock_t lock; + struct timer_list timer; + int timeout; + int need_sync; + int next_ino; + ino_t *inodes; +}; + +/** + * struct ubifs_bud - bud logical eraseblock. + * @lnum: logical eraseblock number + * @start: where the (uncommitted) bud data starts + * @jhead: journal head number this bud belongs to + * @list: link in the list buds belonging to the same journal head + * @rb: link in the tree of all buds + */ +struct ubifs_bud { + int lnum; + int start; + int jhead; + struct list_head list; + struct rb_node rb; +}; + +/** + * struct ubifs_jhead - journal head. + * @wbuf: head's write-buffer + * @buds_list: list of bud LEBs belonging to this journal head + * + * Note, the @buds list is protected by the @c->buds_lock. + */ +struct ubifs_jhead { + struct ubifs_wbuf wbuf; + struct list_head buds_list; +}; + +/** + * struct ubifs_zbranch - key/coordinate/length branch stored in znodes. + * @key: key + * @znode: znode address in memory + * @lnum: LEB number of the indexing node + * @offs: offset of the indexing node within @lnum + * @len: target node length + */ +struct ubifs_zbranch { + union ubifs_key key; + union { + struct ubifs_znode *znode; + void *leaf; + }; + int lnum; + int offs; + int len; +}; + +/** + * struct ubifs_znode - in-memory representation of an indexing node. + * @parent: parent znode or NULL if it is the root + * @cnext: next znode to commit + * @flags: znode flags (%DIRTY_ZNODE, %COW_ZNODE or %OBSOLETE_ZNODE) + * @time: last access time (seconds) + * @level: level of the entry in the TNC tree + * @child_cnt: count of child znodes + * @iip: index in parent's zbranch array + * @alt: lower bound of key range has altered i.e. child inserted at slot 0 + * @lnum: LEB number of the corresponding indexing node + * @offs: offset of the corresponding indexing node + * @len: length of the corresponding indexing node + * @zbranch: array of znode branches (@c->fanout elements) + */ +struct ubifs_znode { + struct ubifs_znode *parent; + struct ubifs_znode *cnext; + unsigned long flags; + unsigned long time; + int level; + int child_cnt; + int iip; + int alt; +#ifdef CONFIG_UBIFS_FS_DEBUG + int lnum, offs, len; +#endif + struct ubifs_zbranch zbranch[]; +}; + +/** + * struct ubifs_node_range - node length range description data structure. + * @len: fixed node length + * @min_len: minimum possible node length + * @max_len: maximum possible node length + * + * If @max_len is %0, the node has fixed length @len. + */ +struct ubifs_node_range { + union { + int len; + int min_len; + }; + int max_len; +}; + +/** + * struct ubifs_compressor - UBIFS compressor description structure. + * @compr_type: compressor type (%UBIFS_COMPR_LZO, etc) + * @cc: cryptoapi compressor handle + * @comp_mutex: mutex used during compression + * @decomp_mutex: mutex used during decompression + * @name: compressor name + * @capi_name: cryptoapi compressor name + */ +struct ubifs_compressor { + int compr_type; + struct crypto_comp *cc; + struct mutex *comp_mutex; + struct mutex *decomp_mutex; + const char *name; + const char *capi_name; +}; + +/** + * struct ubifs_budget_req - budget requirements of an operation. + * + * @fast: non-zero if the budgeting should try to aquire budget quickly and + * should not try to call write-back + * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields + * have to be re-calculated + * @new_page: non-zero if the operation adds a new page + * @dirtied_page: non-zero if the operation makes a page dirty + * @new_dent: non-zero if the operation adds a new directory entry + * @mod_dent: non-zero if the operation removes or modifies an existing + * directory entry + * @new_ino: non-zero if the operation adds a new inode + * @new_ino_d: now much data newly created inode contains + * @dirtied_ino: how many inodes the operation makes dirty + * @dirtied_ino_d: now much data dirtied inode contains + * @idx_growth: how much the index will supposedly grow + * @data_growth: how much new data the operation will supposedly add + * @dd_growth: how much data that makes other data dirty the operation will + * supposedly add + * + * @idx_growth, @data_growth and @dd_growth are not used in budget request. The + * budgeting subsystem caches index and data growth values there to avoid + * re-calculating them when the budget is released. However, if @idx_growth is + * %-1, it is calculated by the release function using other fields. + * + * An inode may contain 4KiB of data at max., thus the widths of @new_ino_d + * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made + * dirty by the re-name operation. + */ +struct ubifs_budget_req { + unsigned int fast:1; + unsigned int recalculate:1; + unsigned int new_page:1; + unsigned int dirtied_page:1; + unsigned int new_dent:1; + unsigned int mod_dent:1; + unsigned int new_ino:1; + unsigned int new_ino_d:13; +#ifndef UBIFS_DEBUG + unsigned int dirtied_ino:4; + unsigned int dirtied_ino_d:15; +#else + /* Not bit-fields to check for overflows */ + unsigned int dirtied_ino; + unsigned int dirtied_ino_d; +#endif + int idx_growth; + int data_growth; + int dd_growth; +}; + +/** + * struct ubifs_orphan - stores the inode number of an orphan. + * @rb: rb-tree node of rb-tree of orphans sorted by inode number + * @list: list head of list of orphans in order added + * @new_list: list head of list of orphans added since the last commit + * @cnext: next orphan to commit + * @dnext: next orphan to delete + * @inum: inode number + * @new: %1 => added since the last commit, otherwise %0 + */ +struct ubifs_orphan { + struct rb_node rb; + struct list_head list; + struct list_head new_list; + struct ubifs_orphan *cnext; + struct ubifs_orphan *dnext; + ino_t inum; + int new; +}; + +/** + * struct ubifs_mount_opts - UBIFS-specific mount options information. + * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast) + */ +struct ubifs_mount_opts { + unsigned int unmount_mode:2; +}; + +/** + * struct ubifs_info - UBIFS file-system description data structure + * (per-superblock). + * @vfs_sb: VFS @struct super_block object + * @bdi: backing device info object to make VFS happy and disable readahead + * + * @highest_inum: highest used inode number + * @vfs_gen: VFS inode generation counter + * @max_sqnum: current global sequence number + * @cmt_no: commit number (last successfully completed commit) + * @cnt_lock: protects @highest_inum, @vfs_gen, and @max_sqnum counters + * @fmt_version: UBIFS on-flash format version + * @uuid: UUID from super block + * + * @lhead_lnum: log head logical eraseblock number + * @lhead_offs: log head offset + * @ltail_lnum: log tail logical eraseblock number (offset is always 0) + * @log_mutex: protects the log, @lhead_lnum, @lhead_offs, @ltail_lnum, and + * @bud_bytes + * @min_log_bytes: minimum required number of bytes in the log + * @cmt_bud_bytes: used during commit to temporarily amount of bytes in + * committed buds + * + * @buds: tree of all buds indexed by bud LEB number + * @bud_bytes: how many bytes of flash is used by buds + * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud + * lists + * @jhead_cnt: count of journal heads + * @jheads: journal heads (head zero is base head) + * @max_bud_bytes: maximum number of bytes allowed in buds + * @bg_bud_bytes: number of bud bytes when background commit is initiated + * @old_buds: buds to be released after commit ends + * @max_bud_cnt: maximum number of buds + * + * @commit_sem: synchronizes committer with other processes + * @cmt_state: commit state + * @cs_lock: commit state lock + * @cmt_wq: wait queue to sleep on if the log is full and a commit is running + * @fast_unmount: do not run journal commit before un-mounting + * @big_lpt: flag that LPT is too big to write whole during commit + * @check_lpt_free: flag that indicates LPT GC may be needed + * @nospace: non-zero if the file-system does not have flash space (used as + * optimization) + * @nospace_rp: the same as @nospace, but additionally means that even reserved + * pool is full + * + * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and + * @calc_idx_sz + * @zroot: zbranch which points to the root index node and znode + * @cnext: next znode to commit + * @enext: next znode to commit to empty space + * @gap_lebs: array of LEBs used by the in-gaps commit method + * @cbuf: commit buffer + * @ileb_buf: buffer for commit in-the-gaps method + * @ileb_len: length of data in ileb_buf + * @ihead_lnum: LEB number of index head + * @ihead_offs: offset of index head + * @ilebs: pre-allocated index LEBs + * @ileb_cnt: number of pre-allocated index LEBs + * @ileb_nxt: next pre-allocated index LEBs + * @old_idx: tree of index nodes obsoleted since the last commit start + * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c + * @new_ihead_lnum: used by debugging to check ihead_lnum + * @new_ihead_offs: used by debugging to check ihead_offs + * + * @mst_node: master node + * @mst_offs: offset of valid master node + * @mst_mutex: protects the master node area, @mst_node, and @mst_offs + * + * @log_lebs: number of logical eraseblocks in the log + * @log_bytes: log size in bytes + * @log_last: last LEB of the log + * @lpt_lebs: number of LEBs used for lprops table + * @lpt_first: first LEB of the lprops table area + * @lpt_last: last LEB of the lprops table area + * @orph_lebs: number of LEBs used for the orphan area + * @orph_first: first LEB of the orphan area + * @orph_last: last LEB of the orphan area + * @main_lebs: count of LEBs in the main area + * @main_first: first LEB of the main area + * @main_bytes: main area size in bytes + * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc) + * + * @key_hash_type: type of the key hash + * @key_hash: direntry key hash function + * @key_fmt: key format + * @key_len: key length + * @fanout: fanout of the index tree (number of links per indexing node) + * + * @min_io_size: minimal input/output unit size + * @min_io_shift: number of bits in @min_io_size minus one + * @leb_size: logical eraseblock size in bytes + * @half_leb_size: half LEB size + * @leb_cnt: count of logical eraseblocks + * @max_leb_cnt: maximum count of logical eraseblocks + * @old_leb_cnt: count of logical eraseblocks before re-size + * @ro_media: the underlying UBI volume is read-only + * + * @dirty_pg_cnt: number of dirty pages (not used) + * @dirty_zn_cnt: number of dirty znodes + * @clean_zn_cnt: number of clean znodes + * + * @budg_idx_growth: amount of bytes budgeted for index growth + * @budg_data_growth: amount of bytes budgeted for cached data + * @budg_dd_growth: amount of bytes budgeted for cached data that will make + * other data dirty + * @budg_uncommitted_idx: amount of bytes were budgeted for growth of the index, + * but which still have to be taken into account because + * the index has not been committed so far + * @space_lock: protects @budg_idx_growth, @budg_data_growth, @budg_dd_growth, + * @budg_uncommited_idx, @min_idx_lebs, @old_idx_sz, and @lst; + * @min_idx_lebs: minimum number of LEBs required for the index + * @old_idx_sz: size of index on flash + * @calc_idx_sz: temporary variable which is used to calculate new index size + * (contains accurate new index size at end of TNC commit start) + * @lst: lprops statistics + * + * @page_budget: budget for a page + * @inode_budget: budget for an inode + * @dent_budget: budget for a directory entry + * + * @ref_node_alsz: size of the LEB reference node aligned to the min. flash + * I/O unit + * @mst_node_alsz: master node aligned size + * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary + * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary + * @max_inode_sz: maximum possible inode size in bytes + * @max_znode_sz: size of znode in bytes + * @dead_wm: LEB dead space watermark + * @dark_wm: LEB dark space watermark + * @block_cnt: count of 4KiB blocks on the FS + * + * @ranges: UBIFS node length ranges + * @ubi: UBI volume descriptor + * @di: UBI device information + * @vi: UBI volume information + * + * @orph_tree: rb-tree of orphan inode numbers + * @orph_list: list of orphan inode numbers in order added + * @orph_new: list of orphan inode numbers added since last commit + * @orph_cnext: next orphan to commit + * @orph_dnext: next orphan to delete + * @orphan_lock: lock for orph_tree and orph_new + * @orph_buf: buffer for orphan nodes + * @new_orphans: number of orphans since last commit + * @cmt_orphans: number of orphans being committed + * @tot_orphans: number of orphans in the rb_tree + * @max_orphans: maximum number of orphans allowed + * @ohead_lnum: orphan head LEB number + * @ohead_offs: orphan head offset + * @no_orphs: non-zero if there are no orphans + * + * @bgt: UBIFS background thread + * @bgt_name: background thread name + * @need_bgt: if background thread should run + * @need_wbuf_sync: if write-buffers have to be synchronized + * + * @gc_lnum: LEB number used for garbage collection + * @sbuf: a buffer of LEB size used by GC and replay for scanning + * @idx_gc: list of index LEBs that have been garbage collected + * @idx_gc_cnt: number of elements on the idx_gc list + * + * @infos_list: links all 'ubifs_info' objects + * @umount_mutex: serializes shrinker and un-mount + * @shrinker_run_no: shrinker run number + * + * @space_bits: number of bits needed to record free or dirty space + * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT + * @lpt_offs_bits: number of bits needed to record an offset in the LPT + * @lpt_spc_bits: number of bits needed to space in the LPT + * @pcnt_bits: number of bits needed to record pnode or nnode number + * @lnum_bits: number of bits needed to record LEB number + * @nnode_sz: size of on-flash nnode + * @pnode_sz: size of on-flash pnode + * @ltab_sz: size of on-flash LPT lprops table + * @lsave_sz: size of on-flash LPT save table + * @pnode_cnt: number of pnodes + * @nnode_cnt: number of nnodes + * @lpt_hght: height of the LPT + * @pnodes_have: number of pnodes in memory + * + * @lp_mutex: protects lprops table and all the other lprops-related fields + * @lpt_lnum: LEB number of the root nnode of the LPT + * @lpt_offs: offset of the root nnode of the LPT + * @nhead_lnum: LEB number of LPT head + * @nhead_offs: offset of LPT head + * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab + * @dirty_nn_cnt: number of dirty nnodes + * @dirty_pn_cnt: number of dirty pnodes + * @lpt_sz: LPT size + * @lpt_nod_buf: buffer for an on-flash nnode or pnode + * @lpt_buf: buffer of LEB size used by LPT + * @nroot: address in memory of the root nnode of the LPT + * @lpt_cnext: next LPT node to commit + * @lpt_heap: array of heaps of categorized lprops + * @dirty_idx: a (reverse sorted) copy of the LPROPS_DIRTY_IDX heap as at + * previous commit start + * @uncat_list: list of un-categorized LEBs + * @empty_list: list of empty LEBs + * @freeable_list: list of freeable non-index LEBs (free + dirty == leb_size) + * @frdi_idx_list: list of freeable index LEBs (free + dirty == leb_size) + * @freeable_cnt: number of freeable LEBs in @freeable_list + * + * @ltab_lnum: LEB number of LPT's |