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Diffstat (limited to 'fs/jfs/jfs_dtree.h')
| -rw-r--r-- | fs/jfs/jfs_dtree.h | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/fs/jfs/jfs_dtree.h b/fs/jfs/jfs_dtree.h new file mode 100644 index 000000000..175828964 --- /dev/null +++ b/fs/jfs/jfs_dtree.h @@ -0,0 +1,256 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) International Business Machines Corp., 2000-2002 + */ +#ifndef _H_JFS_DTREE +#define _H_JFS_DTREE + +/* + * jfs_dtree.h: directory B+-tree manager + */ + +#include "jfs_btree.h" + +typedef union { + struct { + tid_t tid; + struct inode *ip; + u32 ino; + } leaf; + pxd_t xd; +} ddata_t; + + +/* + * entry segment/slot + * + * an entry consists of type dependent head/only segment/slot and + * additional segments/slots linked vi next field; + * N.B. last/only segment of entry is terminated by next = -1; + */ +/* + * directory page slot + */ +struct dtslot { + s8 next; /* 1: */ + s8 cnt; /* 1: */ + __le16 name[15]; /* 30: */ +}; /* (32) */ + + +#define DATASLOTSIZE 16 +#define L2DATASLOTSIZE 4 +#define DTSLOTSIZE 32 +#define L2DTSLOTSIZE 5 +#define DTSLOTHDRSIZE 2 +#define DTSLOTDATASIZE 30 +#define DTSLOTDATALEN 15 + +/* + * internal node entry head/only segment + */ +struct idtentry { + pxd_t xd; /* 8: child extent descriptor */ + + s8 next; /* 1: */ + u8 namlen; /* 1: */ + __le16 name[11]; /* 22: 2-byte aligned */ +}; /* (32) */ + +#define DTIHDRSIZE 10 +#define DTIHDRDATALEN 11 + +/* compute number of slots for entry */ +#define NDTINTERNAL(klen) (DIV_ROUND_UP((4 + (klen)), 15)) + + +/* + * leaf node entry head/only segment + * + * For legacy filesystems, name contains 13 wchars -- no index field + */ +struct ldtentry { + __le32 inumber; /* 4: 4-byte aligned */ + s8 next; /* 1: */ + u8 namlen; /* 1: */ + __le16 name[11]; /* 22: 2-byte aligned */ + __le32 index; /* 4: index into dir_table */ +}; /* (32) */ + +#define DTLHDRSIZE 6 +#define DTLHDRDATALEN_LEGACY 13 /* Old (OS/2) format */ +#define DTLHDRDATALEN 11 + +/* + * dir_table used for directory traversal during readdir + */ + +/* + * Keep persistent index for directory entries + */ +#define DO_INDEX(INODE) (JFS_SBI((INODE)->i_sb)->mntflag & JFS_DIR_INDEX) + +/* + * Maximum entry in inline directory table + */ +#define MAX_INLINE_DIRTABLE_ENTRY 13 + +struct dir_table_slot { + u8 rsrvd; /* 1: */ + u8 flag; /* 1: 0 if free */ + u8 slot; /* 1: slot within leaf page of entry */ + u8 addr1; /* 1: upper 8 bits of leaf page address */ + __le32 addr2; /* 4: lower 32 bits of leaf page address -OR- + index of next entry when this entry was deleted */ +}; /* (8) */ + +/* + * flag values + */ +#define DIR_INDEX_VALID 1 +#define DIR_INDEX_FREE 0 + +#define DTSaddress(dir_table_slot, address64)\ +{\ + (dir_table_slot)->addr1 = ((u64)address64) >> 32;\ + (dir_table_slot)->addr2 = __cpu_to_le32((address64) & 0xffffffff);\ +} + +#define addressDTS(dts)\ + ( ((s64)((dts)->addr1)) << 32 | __le32_to_cpu((dts)->addr2) ) + +/* compute number of slots for entry */ +#define NDTLEAF_LEGACY(klen) (DIV_ROUND_UP((2 + (klen)), 15)) +#define NDTLEAF NDTINTERNAL + + +/* + * directory root page (in-line in on-disk inode): + * + * cf. dtpage_t below. + */ +typedef union { + struct { + struct dasd DASD; /* 16: DASD limit/usage info */ + + u8 flag; /* 1: */ + u8 nextindex; /* 1: next free entry in stbl */ + s8 freecnt; /* 1: free count */ + s8 freelist; /* 1: freelist header */ + + __le32 idotdot; /* 4: parent inode number */ + + s8 stbl[8]; /* 8: sorted entry index table */ + } header; /* (32) */ + + struct dtslot slot[9]; +} dtroot_t; + +#define PARENT(IP) \ + (le32_to_cpu(JFS_IP(IP)->i_dtroot.header.idotdot)) + +#define DTROOTMAXSLOT 9 + +#define dtEmpty(IP) (JFS_IP(IP)->i_dtroot.header.nextindex == 0) + + +/* + * directory regular page: + * + * entry slot array of 32 byte slot + * + * sorted entry slot index table (stbl): + * contiguous slots at slot specified by stblindex, + * 1-byte per entry + * 512 byte block: 16 entry tbl (1 slot) + * 1024 byte block: 32 entry tbl (1 slot) + * 2048 byte block: 64 entry tbl (2 slot) + * 4096 byte block: 128 entry tbl (4 slot) + * + * data area: + * 512 byte block: 16 - 2 = 14 slot + * 1024 byte block: 32 - 2 = 30 slot + * 2048 byte block: 64 - 3 = 61 slot + * 4096 byte block: 128 - 5 = 123 slot + * + * N.B. index is 0-based; index fields refer to slot index + * except nextindex which refers to entry index in stbl; + * end of entry stot list or freelist is marked with -1. + */ +typedef union { + struct { + __le64 next; /* 8: next sibling */ + __le64 prev; /* 8: previous sibling */ + + u8 flag; /* 1: */ + u8 nextindex; /* 1: next entry index in stbl */ + s8 freecnt; /* 1: */ + s8 freelist; /* 1: slot index of head of freelist */ + + u8 maxslot; /* 1: number of slots in page slot[] */ + u8 stblindex; /* 1: slot index of start of stbl */ + u8 rsrvd[2]; /* 2: */ + + pxd_t self; /* 8: self pxd */ + } header; /* (32) */ + + struct dtslot slot[128]; +} dtpage_t; + +#define DTPAGEMAXSLOT 128 + +#define DT8THPGNODEBYTES 512 +#define DT8THPGNODETSLOTS 1 +#define DT8THPGNODESLOTS 16 + +#define DTQTRPGNODEBYTES 1024 +#define DTQTRPGNODETSLOTS 1 +#define DTQTRPGNODESLOTS 32 + +#define DTHALFPGNODEBYTES 2048 +#define DTHALFPGNODETSLOTS 2 +#define DTHALFPGNODESLOTS 64 + +#define DTFULLPGNODEBYTES 4096 +#define DTFULLPGNODETSLOTS 4 +#define DTFULLPGNODESLOTS 128 + +#define DTENTRYSTART 1 + +/* get sorted entry table of the page */ +#define DT_GETSTBL(p) ( ((p)->header.flag & BT_ROOT) ?\ + ((dtroot_t *)(p))->header.stbl : \ + (s8 *)&(p)->slot[(p)->header.stblindex] ) + +/* + * Flags for dtSearch + */ +#define JFS_CREATE 1 +#define JFS_LOOKUP 2 +#define JFS_REMOVE 3 +#define JFS_RENAME 4 + +/* + * Maximum file offset for directories. + */ +#define DIREND INT_MAX + +/* + * external declarations + */ +extern void dtInitRoot(tid_t tid, struct inode *ip, u32 idotdot); + +extern int dtSearch(struct inode *ip, struct component_name * key, + ino_t * data, struct btstack * btstack, int flag); + +extern int dtInsert(tid_t tid, struct inode *ip, struct component_name * key, + ino_t * ino, struct btstack * btstack); + +extern int dtDelete(tid_t tid, struct inode *ip, struct component_name * key, + ino_t * data, int flag); + +extern int dtModify(tid_t tid, struct inode *ip, struct component_name * key, + ino_t * orig_ino, ino_t new_ino, int flag); + +extern int jfs_readdir(struct file *file, struct dir_context *ctx); +#endif /* !_H_JFS_DTREE */ |