[linux-block.git] / fs / xfs / libxfs / xfs_da_btree.h

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
 * Copyright (c) 2013 Red Hat, Inc.
 * All Rights Reserved.
 */
#ifndef __XFS_DA_BTREE_H__
#define	__XFS_DA_BTREE_H__

struct xfs_inode;
struct xfs_trans;
struct zone;
struct xfs_dir_ops;

/*
 * Directory/attribute geometry information. There will be one of these for each
 * data fork type, and it will be passed around via the xfs_da_args. Global
 * structures will be attached to the xfs_mount.
 */
struct xfs_da_geometry {
	unsigned int	blksize;	/* da block size in bytes */
	unsigned int	fsbcount;	/* da block size in filesystem blocks */
	uint8_t		fsblog;		/* log2 of _filesystem_ block size */
	uint8_t		blklog;		/* log2 of da block size */
	unsigned int	node_hdr_size;	/* danode header size in bytes */
	unsigned int	node_ents;	/* # of entries in a danode */
	unsigned int	magicpct;	/* 37% of block size in bytes */
	xfs_dablk_t	datablk;	/* blockno of dir data v2 */
	unsigned int	leaf_hdr_size;	/* dir2 leaf header size */
	unsigned int	leaf_max_ents;	/* # of entries in dir2 leaf */
	xfs_dablk_t	leafblk;	/* blockno of leaf data v2 */
	unsigned int	free_hdr_size;	/* dir2 free header size */
	unsigned int	free_max_bests;	/* # of bests entries in dir2 free */
	xfs_dablk_t	freeblk;	/* blockno of free data v2 */
};

/*========================================================================
 * Btree searching and modification structure definitions.
 *========================================================================*/

/*
 * Search comparison results
 */
enum xfs_dacmp {
	XFS_CMP_DIFFERENT,	/* names are completely different */
	XFS_CMP_EXACT,		/* names are exactly the same */
	XFS_CMP_CASE		/* names are same but differ in case */
};

/*
 * Structure to ease passing around component names.
 */
typedef struct xfs_da_args {
	struct xfs_da_geometry *geo;	/* da block geometry */
	const uint8_t		*name;		/* string (maybe not NULL terminated) */
	int		namelen;	/* length of string (maybe no NULL) */
	uint8_t		filetype;	/* filetype of inode for directories */
	uint8_t		*value;		/* set of bytes (maybe contain NULLs) */
	int		valuelen;	/* length of value */
	int		flags;		/* argument flags (eg: ATTR_NOCREATE) */
	xfs_dahash_t	hashval;	/* hash value of name */
	xfs_ino_t	inumber;	/* input/output inode number */
	struct xfs_inode *dp;		/* directory inode to manipulate */
	struct xfs_trans *trans;	/* current trans (changes over time) */
	xfs_extlen_t	total;		/* total blocks needed, for 1st bmap */
	int		whichfork;	/* data or attribute fork */
	xfs_dablk_t	blkno;		/* blkno of attr leaf of interest */
	int		index;		/* index of attr of interest in blk */
	xfs_dablk_t	rmtblkno;	/* remote attr value starting blkno */
	int		rmtblkcnt;	/* remote attr value block count */
	int		rmtvaluelen;	/* remote attr value length in bytes */
	xfs_dablk_t	blkno2;		/* blkno of 2nd attr leaf of interest */
	int		index2;		/* index of 2nd attr in blk */
	xfs_dablk_t	rmtblkno2;	/* remote attr value starting blkno */
	int		rmtblkcnt2;	/* remote attr value block count */
	int		rmtvaluelen2;	/* remote attr value length in bytes */
	int		op_flags;	/* operation flags */
	enum xfs_dacmp	cmpresult;	/* name compare result for lookups */
} xfs_da_args_t;

/*
 * Operation flags:
 */
#define XFS_DA_OP_JUSTCHECK	0x0001	/* check for ok with no space */
#define XFS_DA_OP_RENAME	0x0002	/* this is an atomic rename op */
#define XFS_DA_OP_ADDNAME	0x0004	/* this is an add operation */
#define XFS_DA_OP_OKNOENT	0x0008	/* lookup/add op, ENOENT ok, else die */
#define XFS_DA_OP_CILOOKUP	0x0010	/* lookup to return CI name if found */
#define XFS_DA_OP_ALLOCVAL	0x0020	/* lookup to alloc buffer if found  */

#define XFS_DA_OP_FLAGS \
	{ XFS_DA_OP_JUSTCHECK,	"JUSTCHECK" }, \
	{ XFS_DA_OP_RENAME,	"RENAME" }, \
	{ XFS_DA_OP_ADDNAME,	"ADDNAME" }, \
	{ XFS_DA_OP_OKNOENT,	"OKNOENT" }, \
	{ XFS_DA_OP_CILOOKUP,	"CILOOKUP" }, \
	{ XFS_DA_OP_ALLOCVAL,	"ALLOCVAL" }

/*
 * Storage for holding state during Btree searches and split/join ops.
 *
 * Only need space for 5 intermediate nodes.  With a minimum of 62-way
 * fanout to the Btree, we can support over 900 million directory blocks,
 * which is slightly more than enough.
 */
typedef struct xfs_da_state_blk {
	struct xfs_buf	*bp;		/* buffer containing block */
	xfs_dablk_t	blkno;		/* filesystem blkno of buffer */
	xfs_daddr_t	disk_blkno;	/* on-disk blkno (in BBs) of buffer */
	int		index;		/* relevant index into block */
	xfs_dahash_t	hashval;	/* last hash value in block */
	int		magic;		/* blk's magic number, ie: blk type */
} xfs_da_state_blk_t;

typedef struct xfs_da_state_path {
	int			active;		/* number of active levels */
	xfs_da_state_blk_t	blk[XFS_DA_NODE_MAXDEPTH];
} xfs_da_state_path_t;

typedef struct xfs_da_state {
	xfs_da_args_t		*args;		/* filename arguments */
	struct xfs_mount	*mp;		/* filesystem mount point */
	xfs_da_state_path_t	path;		/* search/split paths */
	xfs_da_state_path_t	altpath;	/* alternate path for join */
	unsigned char		inleaf;		/* insert into 1->lf, 0->splf */
	unsigned char		extravalid;	/* T/F: extrablk is in use */
	unsigned char		extraafter;	/* T/F: extrablk is after new */
	xfs_da_state_blk_t	extrablk;	/* for double-splits on leaves */
						/* for dirv2 extrablk is data */
} xfs_da_state_t;

/*
 * In-core version of the node header to abstract the differences in the v2 and
 * v3 disk format of the headers. Callers need to convert to/from disk format as
 * appropriate.
 */
struct xfs_da3_icnode_hdr {
	uint32_t		forw;
	uint32_t		back;
	uint16_t		magic;
	uint16_t		count;
	uint16_t		level;

	/*
	 * Pointer to the on-disk format entries, which are behind the
	 * variable size (v4 vs v5) header in the on-disk block.
	 */
	struct xfs_da_node_entry *btree;
};

/*
 * Utility macros to aid in logging changed structure fields.
 */
#define XFS_DA_LOGOFF(BASE, ADDR)	((char *)(ADDR) - (char *)(BASE))
#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE)	\
		(uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
		(uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)

/*
 * Name ops for directory and/or attr name operations
 */
struct xfs_nameops {
	xfs_dahash_t	(*hashname)(struct xfs_name *);
	enum xfs_dacmp	(*compname)(struct xfs_da_args *,
					const unsigned char *, int);
};


/*========================================================================
 * Function prototypes.
 *========================================================================*/

/*
 * Routines used for growing the Btree.
 */
int	xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno,
			    int level, struct xfs_buf **bpp, int whichfork);
int	xfs_da3_split(xfs_da_state_t *state);

/*
 * Routines used for shrinking the Btree.
 */
int	xfs_da3_join(xfs_da_state_t *state);
void	xfs_da3_fixhashpath(struct xfs_da_state *state,
			    struct xfs_da_state_path *path_to_to_fix);

/*
 * Routines used for finding things in the Btree.
 */
int	xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result);
int	xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
					 int forward, int release, int *result);
/*
 * Utility routines.
 */
int	xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
				       xfs_da_state_blk_t *new_blk);
int	xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp,
			 xfs_dablk_t bno, xfs_daddr_t mappedbno,
			 struct xfs_buf **bpp, int which_fork);

/*
 * Utility routines.
 */
int	xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
int	xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno,
			      int count);
int	xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
			      xfs_dablk_t bno, xfs_daddr_t mappedbno,
			      struct xfs_buf **bp, int whichfork);
int	xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
			       xfs_dablk_t bno, xfs_daddr_t mappedbno,
			       struct xfs_buf **bpp, int whichfork,
			       const struct xfs_buf_ops *ops);
int	xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno,
				xfs_daddr_t mapped_bno, int whichfork,
				const struct xfs_buf_ops *ops);
int	xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
					  struct xfs_buf *dead_buf);

uint xfs_da_hashname(const uint8_t *name_string, int name_length);
enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,
				const unsigned char *name, int len);


xfs_da_state_t *xfs_da_state_alloc(void);
void xfs_da_state_free(xfs_da_state_t *state);

void	xfs_da3_node_hdr_from_disk(struct xfs_mount *mp,
		struct xfs_da3_icnode_hdr *to, struct xfs_da_intnode *from);
void	xfs_da3_node_hdr_to_disk(struct xfs_mount *mp,
		struct xfs_da_intnode *to, struct xfs_da3_icnode_hdr *from);

extern struct kmem_zone *xfs_da_state_zone;
extern const struct xfs_nameops xfs_default_nameops;

#endif	/* __XFS_DA_BTREE_H__ */
Commit	Line	Data
0b61f8a4	1	// SPDX-License-Identifier: GPL-2.0
1da177e4	2	/*
7b718769	3	* Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
f5ea1100	4	* Copyright (c) 2013 Red Hat, Inc.
7b718769	5	* All Rights Reserved.
1da177e4 LT	6	*/
	7	#ifndef __XFS_DA_BTREE_H__
	8	#define __XFS_DA_BTREE_H__
	9
1da177e4	10	struct xfs_inode;
1da177e4 LT	11	struct xfs_trans;
1da177e4 LT	12	struct zone;
32c5483a	13	struct xfs_dir_ops;
1da177e4	14
0650b554 DC	15	/*
	16	* Directory/attribute geometry information. There will be one of these for each
	17	* data fork type, and it will be passed around via the xfs_da_args. Global
	18	* structures will be attached to the xfs_mount.
	19	*/
	20	struct xfs_da_geometry {
b16be561 CH	21	unsigned int blksize; /* da block size in bytes */
b16be561 CH	22	unsigned int fsbcount; /* da block size in filesystem blocks */
0650b554 DC	23	uint8_t fsblog; /* log2 of _filesystem_ block size */
0650b554 DC	24	uint8_t blklog; /* log2 of da block size */
3b344413	25	unsigned int node_hdr_size; /* danode header size in bytes */
b16be561 CH	26	unsigned int node_ents; /* # of entries in a danode */
b16be561 CH	27	unsigned int magicpct; /* 37% of block size in bytes */
0650b554	28	xfs_dablk_t datablk; /* blockno of dir data v2 */
545910bc	29	unsigned int leaf_hdr_size; /* dir2 leaf header size */
478c7835	30	unsigned int leaf_max_ents; /* # of entries in dir2 leaf */
0650b554	31	xfs_dablk_t leafblk; /* blockno of leaf data v2 */
ed1d612f	32	unsigned int free_hdr_size; /* dir2 free header size */
5893e4fe	33	unsigned int free_max_bests; /* # of bests entries in dir2 free */
0650b554 DC	34	xfs_dablk_t freeblk; /* blockno of free data v2 */
	35	};
	36
1da177e4 LT	37	/*========================================================================
	38	* Btree searching and modification structure definitions.
	39	========================================================================/
	40
5163f95a BN	41	/*
	42	* Search comparison results
	43	*/
	44	enum xfs_dacmp {
	45	XFS_CMP_DIFFERENT, /* names are completely different */
	46	XFS_CMP_EXACT, /* names are exactly the same */
	47	XFS_CMP_CASE /* names are same but differ in case */
	48	};
	49
1da177e4 LT	50	/*
	51	* Structure to ease passing around component names.
	52	*/
	53	typedef struct xfs_da_args {
0650b554	54	struct xfs_da_geometry geo; / da block geometry */
c8ce540d	55	const uint8_t name; / string (maybe not NULL terminated) */
1da177e4	56	int namelen; /* length of string (maybe no NULL) */
c8ce540d DW	57	uint8_t filetype; /* filetype of inode for directories */
c8ce540d DW	58	uint8_t value; / set of bytes (maybe contain NULLs) */
1da177e4 LT	59	int valuelen; /* length of value */
	60	int flags; /* argument flags (eg: ATTR_NOCREATE) */
	61	xfs_dahash_t hashval; /* hash value of name */
	62	xfs_ino_t inumber; /* input/output inode number */
	63	struct xfs_inode dp; / directory inode to manipulate */
1da177e4 LT	64	struct xfs_trans trans; / current trans (changes over time) */
	65	xfs_extlen_t total; /* total blocks needed, for 1st bmap */
	66	int whichfork; /* data or attribute fork */
	67	xfs_dablk_t blkno; /* blkno of attr leaf of interest */
	68	int index; /* index of attr of interest in blk */
	69	xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
	70	int rmtblkcnt; /* remote attr value block count */
8275cdd0	71	int rmtvaluelen; /* remote attr value length in bytes */
1da177e4 LT	72	xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
	73	int index2; /* index of 2nd attr in blk */
	74	xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
	75	int rmtblkcnt2; /* remote attr value block count */
8275cdd0	76	int rmtvaluelen2; /* remote attr value length in bytes */
6a178100	77	int op_flags; /* operation flags */
5163f95a	78	enum xfs_dacmp cmpresult; /* name compare result for lookups */
1da177e4 LT	79	} xfs_da_args_t;
1da177e4 LT	80
6a178100 BN	81	/*
	82	* Operation flags:
	83	*/
	84	#define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */
	85	#define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */
	86	#define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */
	87	#define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
384f3ced	88	#define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
ddbca70c	89	#define XFS_DA_OP_ALLOCVAL 0x0020 /* lookup to alloc buffer if found */
6a178100	90
0b1b213f CH	91	#define XFS_DA_OP_FLAGS \
	92	{ XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
	93	{ XFS_DA_OP_RENAME, "RENAME" }, \
	94	{ XFS_DA_OP_ADDNAME, "ADDNAME" }, \
	95	{ XFS_DA_OP_OKNOENT, "OKNOENT" }, \
ddbca70c DC	96	{ XFS_DA_OP_CILOOKUP, "CILOOKUP" }, \
ddbca70c DC	97	{ XFS_DA_OP_ALLOCVAL, "ALLOCVAL" }
0b1b213f	98
1da177e4 LT	99	/*
	100	* Storage for holding state during Btree searches and split/join ops.
	101	*
	102	* Only need space for 5 intermediate nodes. With a minimum of 62-way
	103	* fanout to the Btree, we can support over 900 million directory blocks,
	104	* which is slightly more than enough.
	105	*/
	106	typedef struct xfs_da_state_blk {
1d9025e5	107	struct xfs_buf bp; / buffer containing block */
1da177e4 LT	108	xfs_dablk_t blkno; /* filesystem blkno of buffer */
	109	xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
	110	int index; /* relevant index into block */
	111	xfs_dahash_t hashval; /* last hash value in block */
	112	int magic; /* blk's magic number, ie: blk type */
	113	} xfs_da_state_blk_t;
	114
	115	typedef struct xfs_da_state_path {
	116	int active; /* number of active levels */
	117	xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
	118	} xfs_da_state_path_t;
	119
	120	typedef struct xfs_da_state {
	121	xfs_da_args_t args; / filename arguments */
	122	struct xfs_mount mp; / filesystem mount point */
1da177e4 LT	123	xfs_da_state_path_t path; /* search/split paths */
	124	xfs_da_state_path_t altpath; /* alternate path for join */
	125	unsigned char inleaf; /* insert into 1->lf, 0->splf */
	126	unsigned char extravalid; /* T/F: extrablk is in use */
	127	unsigned char extraafter; /* T/F: extrablk is after new */
9da096fd	128	xfs_da_state_blk_t extrablk; /* for double-splits on leaves */
1da177e4 LT	129	/* for dirv2 extrablk is data */
	130	} xfs_da_state_t;
	131
a39f089a CH	132	/*
	133	* In-core version of the node header to abstract the differences in the v2 and
	134	* v3 disk format of the headers. Callers need to convert to/from disk format as
	135	* appropriate.
	136	*/
	137	struct xfs_da3_icnode_hdr {
	138	uint32_t forw;
	139	uint32_t back;
	140	uint16_t magic;
	141	uint16_t count;
	142	uint16_t level;
51908ca7 CH	143
	144	/*
	145	* Pointer to the on-disk format entries, which are behind the
	146	* variable size (v4 vs v5) header in the on-disk block.
	147	*/
	148	struct xfs_da_node_entry *btree;
a39f089a CH	149	};
a39f089a CH	150
1da177e4 LT	151	/*
	152	* Utility macros to aid in logging changed structure fields.
	153	*/
	154	#define XFS_DA_LOGOFF(BASE, ADDR) ((char )(ADDR) - (char )(BASE))
	155	#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
	156	(uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
	157	(uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
	158
5163f95a BN	159	/*
	160	* Name ops for directory and/or attr name operations
	161	*/
	162	struct xfs_nameops {
	163	xfs_dahash_t (hashname)(struct xfs_name );
2bc75421 DC	164	enum xfs_dacmp (compname)(struct xfs_da_args ,
2bc75421 DC	165	const unsigned char *, int);
5163f95a BN	166	};
5163f95a BN	167
1da177e4	168
1da177e4	169	/*========================================================================
847fff5c	170	* Function prototypes.
1da177e4 LT	171	========================================================================/
	172
	173	/*
	174	* Routines used for growing the Btree.
	175	*/
f5ea1100 DC	176	int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno,
	177	int level, struct xfs_buf **bpp, int whichfork);
	178	int xfs_da3_split(xfs_da_state_t *state);
1da177e4 LT	179
	180	/*
	181	* Routines used for shrinking the Btree.
	182	*/
f5ea1100 DC	183	int xfs_da3_join(xfs_da_state_t *state);
	184	void xfs_da3_fixhashpath(struct xfs_da_state *state,
	185	struct xfs_da_state_path *path_to_to_fix);
1da177e4 LT	186
	187	/*
	188	* Routines used for finding things in the Btree.
	189	*/
f5ea1100 DC	190	int xfs_da3_node_lookup_int(xfs_da_state_t state, int result);
f5ea1100 DC	191	int xfs_da3_path_shift(xfs_da_state_t state, xfs_da_state_path_t path,
1da177e4 LT	192	int forward, int release, int *result);
	193	/*
	194	* Utility routines.
	195	*/
f5ea1100	196	int xfs_da3_blk_link(xfs_da_state_t state, xfs_da_state_blk_t old_blk,
1da177e4	197	xfs_da_state_blk_t *new_blk);
f5ea1100	198	int xfs_da3_node_read(struct xfs_trans tp, struct xfs_inode dp,
d9392a4b DC	199	xfs_dablk_t bno, xfs_daddr_t mappedbno,
d9392a4b DC	200	struct xfs_buf **bpp, int which_fork);
1da177e4 LT	201
	202	/*
	203	* Utility routines.
	204	*/
	205	int xfs_da_grow_inode(xfs_da_args_t args, xfs_dablk_t new_blkno);
77936d02 CH	206	int xfs_da_grow_inode_int(struct xfs_da_args args, xfs_fileoff_t bno,
77936d02 CH	207	int count);
1da177e4 LT	208	int xfs_da_get_buf(struct xfs_trans trans, struct xfs_inode dp,
1da177e4 LT	209	xfs_dablk_t bno, xfs_daddr_t mappedbno,
1d9025e5	210	struct xfs_buf **bp, int whichfork);
1da177e4 LT	211	int xfs_da_read_buf(struct xfs_trans trans, struct xfs_inode dp,
1da177e4 LT	212	xfs_dablk_t bno, xfs_daddr_t mappedbno,
4bb20a83	213	struct xfs_buf **bpp, int whichfork,
1813dd64	214	const struct xfs_buf_ops *ops);
7a652bbe	215	int xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno,
9df2dd0b ES	216	xfs_daddr_t mapped_bno, int whichfork,
9df2dd0b ES	217	const struct xfs_buf_ops *ops);
1da177e4	218	int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
1d9025e5	219	struct xfs_buf *dead_buf);
1da177e4	220
c8ce540d	221	uint xfs_da_hashname(const uint8_t *name_string, int name_length);
5163f95a	222	enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,
2bc75421	223	const unsigned char *name, int len);
5163f95a BN	224
5163f95a BN	225
1da177e4 LT	226	xfs_da_state_t *xfs_da_state_alloc(void);
1da177e4 LT	227	void xfs_da_state_free(xfs_da_state_t *state);
1da177e4	228
f475dc4d CH	229	void xfs_da3_node_hdr_from_disk(struct xfs_mount *mp,
f475dc4d CH	230	struct xfs_da3_icnode_hdr to, struct xfs_da_intnode from);
e1c8af1e CH	231	void xfs_da3_node_hdr_to_disk(struct xfs_mount *mp,
e1c8af1e CH	232	struct xfs_da_intnode to, struct xfs_da3_icnode_hdr from);
f475dc4d	233
1da177e4	234	extern struct kmem_zone *xfs_da_state_zone;
24418492	235	extern const struct xfs_nameops xfs_default_nameops;
1da177e4 LT	236
1da177e4 LT	237	#endif /* __XFS_DA_BTREE_H__ */