[mirror_ubuntu-zesty-kernel.git] / fs / xfs / libxfs / xfs_da_btree.h

/*
 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
 * Copyright (c) 2013 Red Hat, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_DA_BTREE_H__
#define	__XFS_DA_BTREE_H__

struct xfs_defer_ops;
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 {
	int		blksize;	/* da block size in bytes */
	int		fsbcount;	/* da block size in filesystem blocks */
	uint8_t		fsblog;		/* log2 of _filesystem_ block size */
	uint8_t		blklog;		/* log2 of da block size */
	uint		node_ents;	/* # of entries in a danode */
	int		magicpct;	/* 37% of block size in bytes */
	xfs_dablk_t	datablk;	/* blockno of dir data v2 */
	xfs_dablk_t	leafblk;	/* blockno of leaf data v2 */
	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 */
	xfs_fsblock_t	*firstblock;	/* ptr to firstblock for bmap calls */
	struct xfs_defer_ops *dfops;	/* ptr to freelist for bmap_finish */
	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_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" }

/*
 * 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;

/*
 * 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);

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

#endif	/* __XFS_DA_BTREE_H__ */
Commit	Line	Data
1da177e4	1	/*
7b718769	2	* Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
f5ea1100	3	* Copyright (c) 2013 Red Hat, Inc.
7b718769	4	* All Rights Reserved.
1da177e4	5	*
7b718769 NS	6	* This program is free software; you can redistribute it and/or
7b718769 NS	7	* modify it under the terms of the GNU General Public License as
1da177e4 LT	8	* published by the Free Software Foundation.
1da177e4 LT	9	*
7b718769 NS	10	* This program is distributed in the hope that it would be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
1da177e4	14	*
7b718769 NS	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write the Free Software Foundation,
	17	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
1da177e4 LT	18	*/
	19	#ifndef __XFS_DA_BTREE_H__
	20	#define __XFS_DA_BTREE_H__
	21
310a75a3	22	struct xfs_defer_ops;
1da177e4	23	struct xfs_inode;
1da177e4 LT	24	struct xfs_trans;
1da177e4 LT	25	struct zone;
32c5483a	26	struct xfs_dir_ops;
1da177e4	27
0650b554 DC	28	/*
	29	* Directory/attribute geometry information. There will be one of these for each
	30	* data fork type, and it will be passed around via the xfs_da_args. Global
	31	* structures will be attached to the xfs_mount.
	32	*/
	33	struct xfs_da_geometry {
	34	int blksize; /* da block size in bytes */
	35	int fsbcount; /* da block size in filesystem blocks */
	36	uint8_t fsblog; /* log2 of _filesystem_ block size */
	37	uint8_t blklog; /* log2 of da block size */
	38	uint node_ents; /* # of entries in a danode */
	39	int magicpct; /* 37% of block size in bytes */
	40	xfs_dablk_t datablk; /* blockno of dir data v2 */
	41	xfs_dablk_t leafblk; /* blockno of leaf data v2 */
	42	xfs_dablk_t freeblk; /* blockno of free data v2 */
	43	};
	44
1da177e4 LT	45	/*========================================================================
	46	* Btree searching and modification structure definitions.
	47	========================================================================/
	48
5163f95a BN	49	/*
	50	* Search comparison results
	51	*/
	52	enum xfs_dacmp {
	53	XFS_CMP_DIFFERENT, /* names are completely different */
	54	XFS_CMP_EXACT, /* names are exactly the same */
	55	XFS_CMP_CASE /* names are same but differ in case */
	56	};
	57
1da177e4 LT	58	/*
	59	* Structure to ease passing around component names.
	60	*/
	61	typedef struct xfs_da_args {
0650b554	62	struct xfs_da_geometry geo; / da block geometry */
a5687787	63	const __uint8_t name; / string (maybe not NULL terminated) */
1da177e4	64	int namelen; /* length of string (maybe no NULL) */
0cb97766	65	__uint8_t filetype; /* filetype of inode for directories */
a5687787	66	__uint8_t value; / set of bytes (maybe contain NULLs) */
1da177e4 LT	67	int valuelen; /* length of value */
	68	int flags; /* argument flags (eg: ATTR_NOCREATE) */
	69	xfs_dahash_t hashval; /* hash value of name */
	70	xfs_ino_t inumber; /* input/output inode number */
	71	struct xfs_inode dp; / directory inode to manipulate */
	72	xfs_fsblock_t firstblock; / ptr to firstblock for bmap calls */
2c3234d1	73	struct xfs_defer_ops dfops; / ptr to freelist for bmap_finish */
1da177e4 LT	74	struct xfs_trans trans; / current trans (changes over time) */
	75	xfs_extlen_t total; /* total blocks needed, for 1st bmap */
	76	int whichfork; /* data or attribute fork */
	77	xfs_dablk_t blkno; /* blkno of attr leaf of interest */
	78	int index; /* index of attr of interest in blk */
	79	xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
	80	int rmtblkcnt; /* remote attr value block count */
8275cdd0	81	int rmtvaluelen; /* remote attr value length in bytes */
1da177e4 LT	82	xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
	83	int index2; /* index of 2nd attr in blk */
	84	xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
	85	int rmtblkcnt2; /* remote attr value block count */
8275cdd0	86	int rmtvaluelen2; /* remote attr value length in bytes */
6a178100	87	int op_flags; /* operation flags */
5163f95a	88	enum xfs_dacmp cmpresult; /* name compare result for lookups */
1da177e4 LT	89	} xfs_da_args_t;
1da177e4 LT	90
6a178100 BN	91	/*
	92	* Operation flags:
	93	*/
	94	#define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */
	95	#define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */
	96	#define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */
	97	#define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
384f3ced	98	#define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
6a178100	99
0b1b213f CH	100	#define XFS_DA_OP_FLAGS \
	101	{ XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
	102	{ XFS_DA_OP_RENAME, "RENAME" }, \
	103	{ XFS_DA_OP_ADDNAME, "ADDNAME" }, \
	104	{ XFS_DA_OP_OKNOENT, "OKNOENT" }, \
	105	{ XFS_DA_OP_CILOOKUP, "CILOOKUP" }
	106
1da177e4 LT	107	/*
	108	* Storage for holding state during Btree searches and split/join ops.
	109	*
	110	* Only need space for 5 intermediate nodes. With a minimum of 62-way
	111	* fanout to the Btree, we can support over 900 million directory blocks,
	112	* which is slightly more than enough.
	113	*/
	114	typedef struct xfs_da_state_blk {
1d9025e5	115	struct xfs_buf bp; / buffer containing block */
1da177e4 LT	116	xfs_dablk_t blkno; /* filesystem blkno of buffer */
	117	xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
	118	int index; /* relevant index into block */
	119	xfs_dahash_t hashval; /* last hash value in block */
	120	int magic; /* blk's magic number, ie: blk type */
	121	} xfs_da_state_blk_t;
	122
	123	typedef struct xfs_da_state_path {
	124	int active; /* number of active levels */
	125	xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
	126	} xfs_da_state_path_t;
	127
	128	typedef struct xfs_da_state {
	129	xfs_da_args_t args; / filename arguments */
	130	struct xfs_mount mp; / filesystem mount point */
1da177e4 LT	131	xfs_da_state_path_t path; /* search/split paths */
	132	xfs_da_state_path_t altpath; /* alternate path for join */
	133	unsigned char inleaf; /* insert into 1->lf, 0->splf */
	134	unsigned char extravalid; /* T/F: extrablk is in use */
	135	unsigned char extraafter; /* T/F: extrablk is after new */
9da096fd	136	xfs_da_state_blk_t extrablk; /* for double-splits on leaves */
1da177e4 LT	137	/* for dirv2 extrablk is data */
	138	} xfs_da_state_t;
	139
	140	/*
	141	* Utility macros to aid in logging changed structure fields.
	142	*/
	143	#define XFS_DA_LOGOFF(BASE, ADDR) ((char )(ADDR) - (char )(BASE))
	144	#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
	145	(uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
	146	(uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
	147
5163f95a BN	148	/*
	149	* Name ops for directory and/or attr name operations
	150	*/
	151	struct xfs_nameops {
	152	xfs_dahash_t (hashname)(struct xfs_name );
2bc75421 DC	153	enum xfs_dacmp (compname)(struct xfs_da_args ,
2bc75421 DC	154	const unsigned char *, int);
5163f95a BN	155	};
5163f95a BN	156
1da177e4	157
1da177e4	158	/*========================================================================
847fff5c	159	* Function prototypes.
1da177e4 LT	160	========================================================================/
	161
	162	/*
	163	* Routines used for growing the Btree.
	164	*/
f5ea1100 DC	165	int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno,
	166	int level, struct xfs_buf **bpp, int whichfork);
	167	int xfs_da3_split(xfs_da_state_t *state);
1da177e4 LT	168
	169	/*
	170	* Routines used for shrinking the Btree.
	171	*/
f5ea1100 DC	172	int xfs_da3_join(xfs_da_state_t *state);
	173	void xfs_da3_fixhashpath(struct xfs_da_state *state,
	174	struct xfs_da_state_path *path_to_to_fix);
1da177e4 LT	175
	176	/*
	177	* Routines used for finding things in the Btree.
	178	*/
f5ea1100 DC	179	int xfs_da3_node_lookup_int(xfs_da_state_t state, int result);
f5ea1100 DC	180	int xfs_da3_path_shift(xfs_da_state_t state, xfs_da_state_path_t path,
1da177e4 LT	181	int forward, int release, int *result);
	182	/*
	183	* Utility routines.
	184	*/
f5ea1100	185	int xfs_da3_blk_link(xfs_da_state_t state, xfs_da_state_blk_t old_blk,
1da177e4	186	xfs_da_state_blk_t *new_blk);
f5ea1100	187	int xfs_da3_node_read(struct xfs_trans tp, struct xfs_inode dp,
d9392a4b DC	188	xfs_dablk_t bno, xfs_daddr_t mappedbno,
d9392a4b DC	189	struct xfs_buf **bpp, int which_fork);
1da177e4 LT	190
	191	/*
	192	* Utility routines.
	193	*/
	194	int xfs_da_grow_inode(xfs_da_args_t args, xfs_dablk_t new_blkno);
77936d02 CH	195	int xfs_da_grow_inode_int(struct xfs_da_args args, xfs_fileoff_t bno,
77936d02 CH	196	int count);
1da177e4 LT	197	int xfs_da_get_buf(struct xfs_trans trans, struct xfs_inode dp,
1da177e4 LT	198	xfs_dablk_t bno, xfs_daddr_t mappedbno,
1d9025e5	199	struct xfs_buf **bp, int whichfork);
1da177e4 LT	200	int xfs_da_read_buf(struct xfs_trans trans, struct xfs_inode dp,
1da177e4 LT	201	xfs_dablk_t bno, xfs_daddr_t mappedbno,
4bb20a83	202	struct xfs_buf **bpp, int whichfork,
1813dd64	203	const struct xfs_buf_ops *ops);
84a3fe64	204	int xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno,
9df2dd0b ES	205	xfs_daddr_t mapped_bno, int whichfork,
9df2dd0b ES	206	const struct xfs_buf_ops *ops);
1da177e4	207	int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
1d9025e5	208	struct xfs_buf *dead_buf);
1da177e4	209
a5687787	210	uint xfs_da_hashname(const __uint8_t *name_string, int name_length);
5163f95a	211	enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,
2bc75421	212	const unsigned char *name, int len);
5163f95a BN	213
5163f95a BN	214
1da177e4 LT	215	xfs_da_state_t *xfs_da_state_alloc(void);
1da177e4 LT	216	void xfs_da_state_free(xfs_da_state_t *state);
1da177e4	217
1da177e4	218	extern struct kmem_zone *xfs_da_state_zone;
24418492	219	extern const struct xfs_nameops xfs_default_nameops;
1da177e4 LT	220
1da177e4 LT	221	#endif /* __XFS_DA_BTREE_H__ */