fs/ubifs/ubifs.h

1 /* SPDX-License-Identifier: GPL-2.0+ */
5  * Copyright (C) 2006-2008 Nokia Corporation
7  * (C) Copyright 2008-2009
19 #include <linux/statfs.h>
20 #include <linux/fs.h>
21 #include <linux/err.h>
22 #include <linux/sched.h>
23 #include <linux/slab.h>
24 #include <linux/vmalloc.h>
25 #include <linux/spinlock.h>
26 #include <linux/mutex.h>
27 #include <linux/rwsem.h>
28 #include <linux/mtd/ubi.h>
29 #include <linux/pagemap.h>
30 #include <linux/backing-dev.h>
31 #include <linux/security.h>
32 #include "ubifs-media.h"
35 #include <asm-generic/atomic-long.h>
39 #include <linux/ctype.h>
40 #include <linux/time.h>
41 #include <linux/math64.h>
42 #include "ubifs-media.h"
59  * We "simulate" the Linux page struct much simpler here
69 /* linux/include/time.h */
87 /* linux/include/dcache.h */
90  * "quick string" -- eases parameter passing, but more importantly
106 /* include/linux/fs.h */
115 	SB_FREEZE_COMPLETE = 4,		/* ->freeze_fs finished successfully */
118 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
159  * Keep mostly read-only and often accessed (especially for
228 	const struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
346 	 * Filesystem subtype.  If non-empty the filesystem type field
361 	 * Saved pool identifier for cleancache (-1 means none)
366 	struct shrinker s_shrink;	/* per-sb shrinker handle */
372 	/* Being remounted read-only */
375 	/* AIO completions deferred from interrupt context */
417 /* include/linux/mount.h */
456  * get_seconds() not really needed in the read-only implmentation
467 #define MAX_LFS_FILESIZE	(((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
473  * These are the fs-independent mount-flags: up to 32 flags are supported
475 #define MS_RDONLY	 1	/* Mount read-only */
504 /* Inode flags - they have nothing to superblock flags now */
508 #define S_APPEND	4	/* Append-only file */
515 #define S_PRIVATE	512	/* Inode is fs-internal */
517 /* include/linux/stat.h */
531 /* include/linux/fs.h */
563 /* linux/include/dcache.h */
570 	struct inode *d_inode;		/* Where the name belongs to - NULL is
588 	void *d_fsdata;			/* fs-specific data */
600 	spin_lock(&dentry->d_lock);  in parent_ino()
601 	res = dentry->d_parent->d_inode->i_ino;  in parent_ino()
602 	spin_unlock(&dentry->d_lock);  in parent_ino()
625 		  (c)->vi.ubi_num, (c)->vi.vol_id, ##__VA_ARGS__)
631 	       (c)->vi.ubi_num, (c)->vi.vol_id, current->pid,       \
636 		(c)->vi.ubi_num, (c)->vi.vol_id, current->pid,      \
641 	       (c)->vi.ubi_num, (c)->vi.vol_id, 0,                  \
646 		(c)->vi.ubi_num, (c)->vi.vol_id, 0,                 \
652  * A variant of 'ubifs_err()' which takes the UBIFS file-sytem description
657 		if (!(c)->probing)                                  \
666 #define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_CACHE_SHIFT - UBIFS_BLOCK_SHIFT)
674  * least 2 LEBs: one for the index head and one for in-the-gaps method (which
684  * Currently we do not support inode number overlapping and re-using, so this
687  * 64-bit inode numbers, but this means more overhead.
701 /* Write-buffer synchronization timeout interval in seconds */
705 /* Maximum possible inode number (only 32-bit inodes are supported now) */
708 /* Number of non-data journal heads */
765 /* Maximum number of data nodes to bulk-read */
825 	SCANNED_EMPTY_SPACE    = -1,
826 	SCANNED_A_NODE         = -2,
827 	SCANNED_A_CORRUPT_NODE = -3,
828 	SCANNED_A_BAD_PAD_NODE = -4,
869  * struct ubifs_old_idx - index node obsoleted since last commit start.
870  * @rb: rb-tree node
889  * struct ubifs_scan_node - UBIFS scanned node information.
909  * struct ubifs_scan_leb - UBIFS scanned LEB information.
925  * struct ubifs_gced_idx_leb - garbage-collected indexing LEB.
930  * This data structure is used to temporary store garbage-collected indexing
931  * LEBs - they are not released immediately, but only after the next commit.
941  * struct ubifs_inode - UBIFS in-memory inode description.
945  *             protected by @c->commit_sem;
950  * @dirty: non-zero if the inode is dirty
951  * @xattr: non-zero if this is an extended attribute inode
952  * @bulk_read: non-zero if bulk-read should be used
953  * @ui_mutex: serializes inode write-back with the rest of VFS operations,
954  *            serializes "clean <-> dirty" state changes, serializes bulk-read,
972  * write-back must not write any of them before we have finished.
974  * The second reason is budgeting - UBIFS has to budget all operations. If an
978  * to have full control over inode "clean <-> dirty" transitions (and pages
980  * does not ask the file-system if it is allowed to do so (there is a notifier,
983  * "clean <-> dirty" transitions.
989  * The @ui_size is a "shadow" variable for @inode->i_size and UBIFS uses
990  * @ui_size instead of @inode->i_size. The reason for this is that UBIFS cannot
991  * make sure @inode->i_size is always changed under @ui_mutex, because it
1020  * struct ubifs_unclean_leb - records a LEB recovered under read-only mode.
1026  * cleaned but was not because UBIFS was mounted read-only. The information
1027  * is used to clean the LEB when remounting to read-write mode.
1039  * LPROPS_DIRTY: dirty > free, dirty >= @c->dead_wm, not index
1040  * LPROPS_DIRTY_IDX: dirty + free > @c->min_idx_node_sze and index
1041  * LPROPS_FREE: free > 0, dirty < @c->dead_wm, not empty, not index
1065  * struct ubifs_lprops - logical eraseblock properties.
1070  * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE)
1071  * @hpos: heap position in heap of same-category lprops (other categories)
1085  * struct ubifs_lpt_lprops - LPT logical eraseblock properties.
1099  * struct ubifs_lp_stats - statistics of eraseblocks in the main area.
1138  * struct ubifs_cnode - LEB Properties Tree common node.
1156  * struct ubifs_pnode - LEB Properties Tree leaf node.
1176  * struct ubifs_nbranch - LEB Properties Tree internal node branch.
1194  * struct ubifs_nnode - LEB Properties Tree internal node.
1214  * struct ubifs_lpt_heap - heap of categorized lprops.
1248  * struct ubifs_wbuf - UBIFS write-buffer.
1249  * @c: UBIFS file-system description object
1250  * @buf: write-buffer (of min. flash I/O unit size)
1251  * @lnum: logical eraseblock number the write-buffer points to
1252  * @offs: write-buffer offset in this logical eraseblock
1253  * @avail: number of bytes available in the write-buffer
1254  * @used:  number of used bytes in the write-buffer
1255  * @size: write-buffer size (in [@c->min_io_size, @c->max_write_size] range)
1258  * @sync_callback: write-buffer synchronization callback
1259  * @io_mutex: serializes write-buffer I/O
1262  * @softlimit: soft write-buffer timeout interval
1265  * @timer: write-buffer timer
1266  * @no_timer: non-zero if this write-buffer does not have a timer
1267  * @need_sync: non-zero if the timer expired and the wbuf needs sync'ing
1271  * The write-buffer synchronization callback is called when the write-buffer is
1273  * write-buffer padding and how much free space is left in the LEB.
1276  * spin-lock or mutex because they are written under both mutex and spin-lock.
1278  * spin-lock. Thus the data between @buf and @buf + @used can be read under
1303  * struct ubifs_bud - bud logical eraseblock.
1319  * struct ubifs_jhead - journal head.
1320  * @wbuf: head's write-buffer
1322  * @grouped: non-zero if UBIFS groups nodes when writing to this journal head
1324  * Note, the @buds list is protected by the @c->buds_lock.
1333  * struct ubifs_zbranch - key/coordinate/length branch stored in znodes.
1352  * struct ubifs_znode - in-memory representation of an indexing node.
1364  * @zbranch: array of znode branches (@c->fanout elements)
1366  * Note! The @lnum, @offs, and @len fields are not really needed - we have them
1385  * struct bu_info - bulk-read information.
1407  * struct ubifs_node_range - node length range description data structure.
1423  * struct ubifs_compressor - UBIFS compressor description structure.
1445  * struct ubifs_budget_req - budget requirements of an operation.
1447  * @fast: non-zero if the budgeting should try to acquire budget quickly and
1448  *        should not try to call write-back
1449  * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields
1450  *               have to be re-calculated
1451  * @new_page: non-zero if the operation adds a new page
1452  * @dirtied_page: non-zero if the operation makes a page dirty
1453  * @new_dent: non-zero if the operation adds a new directory entry
1454  * @mod_dent: non-zero if the operation removes or modifies an existing
1456  * @new_ino: non-zero if the operation adds a new inode
1467  * re-calculating them when the budget is released. However, if @idx_growth is
1468  * %-1, it is calculated by the release function using other fields.
1471  * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made
1472  * dirty by the re-name operation.
1474  * Note, UBIFS aligns node lengths to 8-bytes boundary, so the requester has to
1491 	/* Not bit-fields to check for overflows */
1507  * struct ubifs_orphan - stores the inode number of an orphan.
1508  * @rb: rb-tree node of rb-tree of orphans sorted by inode number
1531  * struct ubifs_mount_opts - UBIFS-specific mount options information.
1533  * @bulk_read: enable/disable bulk-reads (%0 default, %1 disable, %2 enable)
1534  * @chk_data_crc: enable/disable CRC data checking when reading data nodes
1535  *                (%0 default, %1 disable, %2 enable)
1536  * @override_compr: override default compressor (%0 - do not override and use
1537  *                  superblock compressor, %1 - override and use compressor
1551  * struct ubifs_budg_info - UBIFS budgeting information.
1561  * @nospace: non-zero if the file-system does not have flash space (used as
1587  * struct ubifs_info - UBIFS file-system description data structure
1588  * (per-superblock).
1590  * @bdi: backing device info object to make VFS happy and disable read-ahead
1597  * @fmt_version: UBIFS on-flash format version
1612  * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud
1630  * @bulk_read: enable bulk-reads
1639  * @gap_lebs: array of LEBs used by the in-gaps commit method
1641  * @ileb_buf: buffer for commit in-the-gaps method
1645  * @ilebs: pre-allocated index LEBs
1646  * @ileb_cnt: number of pre-allocated index LEBs
1647  * @ileb_nxt: next pre-allocated index LEBs
1654  * @max_bu_buf_len: maximum bulk-read buffer length
1655  * @bu_mutex: protects the pre-allocated bulk-read buffer and @c->bu
1656  * @bu: pre-allocated bulk-read information
1692  *                used to store indexing nodes (@leb_size - @max_idx_node_sz)
1695  * @old_leb_cnt: count of logical eraseblocks before re-size
1696  * @ro_media: the underlying UBI volume is read-only
1697  * @ro_mount: the file-system was mounted as read-only
1713  * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary
1714  * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary
1719  *                data nodes of maximum size - used in free space reporting
1729  * @orph_tree: rb-tree of orphan inode numbers
1742  * @no_orphs: non-zero if there are no orphans
1747  * @need_wbuf_sync: if write-buffers have to be synchronized
1753  * @gc_seq: incremented for every non-index LEB garbage collected
1754  * @gced_lnum: last non-index LEB that was garbage collected
1757  * @umount_mutex: serializes shrinker and un-mount
1766  * @nnode_sz: size of on-flash nnode
1767  * @pnode_sz: size of on-flash pnode
1768  * @ltab_sz: size of on-flash LPT lprops table
1769  * @lsave_sz: size of on-flash LPT save table
1775  * @lp_mutex: protects lprops table and all the other lprops-related fields
1785  * @lpt_nod_buf: buffer for an on-flash nnode or pnode
1792  * @uncat_list: list of un-categorized LEBs
1794  * @freeable_list: list of freeable non-index LEBs (free + dirty == @leb_size)
1811  * @report_rp_size: size of the reserved pool reported to user-space
1816  * @need_recovery: %1 if the file-system needs recovery
1820  * @remounting_rw: %1 while re-mounting from R/O mode to R/W mode
1825  * @unclean_leb_list: LEBs to recover when re-mounting R/O mounted FS to R/W
1827  * @rcvrd_mst_node: recovered master node to write when re-mounting R/O mounted
1830  * @mount_opts: UBIFS-specific mount options
1832  * @dbg: debugging-related information
2047 	/* The below fields are used only during mounting and re-mounting */