linux/fs/xfs/libxfs/xfs_btree.h
Darrick J. Wong a095686a23 xfs: support in-memory btrees
Adapt the generic btree cursor code to be able to create a btree whose
buffers come from a (presumably in-memory) buftarg with a header block
that's specific to in-memory btrees.  We'll connect this to other parts
of online scrub in the next patches.

Note that in-memory btrees always have a block size matching the system
memory page size for efficiency reasons.  There are also a few things we
need to do to finalize a btree update; that's covered in the next patch.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-02-22 12:43:35 -08:00

706 lines
21 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#ifndef __XFS_BTREE_H__
#define __XFS_BTREE_H__
struct xfs_buf;
struct xfs_inode;
struct xfs_mount;
struct xfs_trans;
struct xfs_ifork;
struct xfs_perag;
/*
* Generic key, ptr and record wrapper structures.
*
* These are disk format structures, and are converted where necessary
* by the btree specific code that needs to interpret them.
*/
union xfs_btree_ptr {
__be32 s; /* short form ptr */
__be64 l; /* long form ptr */
};
/*
* The in-core btree key. Overlapping btrees actually store two keys
* per pointer, so we reserve enough memory to hold both. The __*bigkey
* items should never be accessed directly.
*/
union xfs_btree_key {
struct xfs_bmbt_key bmbt;
xfs_bmdr_key_t bmbr; /* bmbt root block */
xfs_alloc_key_t alloc;
struct xfs_inobt_key inobt;
struct xfs_rmap_key rmap;
struct xfs_rmap_key __rmap_bigkey[2];
struct xfs_refcount_key refc;
};
union xfs_btree_rec {
struct xfs_bmbt_rec bmbt;
xfs_bmdr_rec_t bmbr; /* bmbt root block */
struct xfs_alloc_rec alloc;
struct xfs_inobt_rec inobt;
struct xfs_rmap_rec rmap;
struct xfs_refcount_rec refc;
};
/*
* This nonsense is to make -wlint happy.
*/
#define XFS_LOOKUP_EQ ((xfs_lookup_t)XFS_LOOKUP_EQi)
#define XFS_LOOKUP_LE ((xfs_lookup_t)XFS_LOOKUP_LEi)
#define XFS_LOOKUP_GE ((xfs_lookup_t)XFS_LOOKUP_GEi)
struct xfs_btree_ops;
uint32_t xfs_btree_magic(struct xfs_mount *mp, const struct xfs_btree_ops *ops);
/*
* For logging record fields.
*/
#define XFS_BB_MAGIC (1u << 0)
#define XFS_BB_LEVEL (1u << 1)
#define XFS_BB_NUMRECS (1u << 2)
#define XFS_BB_LEFTSIB (1u << 3)
#define XFS_BB_RIGHTSIB (1u << 4)
#define XFS_BB_BLKNO (1u << 5)
#define XFS_BB_LSN (1u << 6)
#define XFS_BB_UUID (1u << 7)
#define XFS_BB_OWNER (1u << 8)
#define XFS_BB_NUM_BITS 5
#define XFS_BB_ALL_BITS ((1u << XFS_BB_NUM_BITS) - 1)
#define XFS_BB_NUM_BITS_CRC 9
#define XFS_BB_ALL_BITS_CRC ((1u << XFS_BB_NUM_BITS_CRC) - 1)
/*
* Generic stats interface
*/
#define XFS_BTREE_STATS_INC(cur, stat) \
XFS_STATS_INC_OFF((cur)->bc_mp, \
(cur)->bc_ops->statoff + __XBTS_ ## stat)
#define XFS_BTREE_STATS_ADD(cur, stat, val) \
XFS_STATS_ADD_OFF((cur)->bc_mp, \
(cur)->bc_ops->statoff + __XBTS_ ## stat, val)
enum xbtree_key_contig {
XBTREE_KEY_GAP = 0,
XBTREE_KEY_CONTIGUOUS,
XBTREE_KEY_OVERLAP,
};
/*
* Decide if these two numeric btree key fields are contiguous, overlapping,
* or if there's a gap between them. @x should be the field from the high
* key and @y should be the field from the low key.
*/
static inline enum xbtree_key_contig xbtree_key_contig(uint64_t x, uint64_t y)
{
x++;
if (x < y)
return XBTREE_KEY_GAP;
if (x == y)
return XBTREE_KEY_CONTIGUOUS;
return XBTREE_KEY_OVERLAP;
}
#define XFS_BTREE_LONG_PTR_LEN (sizeof(__be64))
#define XFS_BTREE_SHORT_PTR_LEN (sizeof(__be32))
enum xfs_btree_type {
XFS_BTREE_TYPE_AG,
XFS_BTREE_TYPE_INODE,
XFS_BTREE_TYPE_MEM,
};
struct xfs_btree_ops {
const char *name;
/* Type of btree - AG-rooted or inode-rooted */
enum xfs_btree_type type;
/* XFS_BTGEO_* flags that determine the geometry of the btree */
unsigned int geom_flags;
/* size of the key, pointer, and record structures */
size_t key_len;
size_t ptr_len;
size_t rec_len;
/* LRU refcount to set on each btree buffer created */
unsigned int lru_refs;
/* offset of btree stats array */
unsigned int statoff;
/* sick mask for health reporting (only for XFS_BTREE_TYPE_AG) */
unsigned int sick_mask;
/* cursor operations */
struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
void (*update_cursor)(struct xfs_btree_cur *src,
struct xfs_btree_cur *dst);
/* update btree root pointer */
void (*set_root)(struct xfs_btree_cur *cur,
const union xfs_btree_ptr *nptr, int level_change);
/* block allocation / freeing */
int (*alloc_block)(struct xfs_btree_cur *cur,
const union xfs_btree_ptr *start_bno,
union xfs_btree_ptr *new_bno,
int *stat);
int (*free_block)(struct xfs_btree_cur *cur, struct xfs_buf *bp);
/* update last record information */
void (*update_lastrec)(struct xfs_btree_cur *cur,
const struct xfs_btree_block *block,
const union xfs_btree_rec *rec,
int ptr, int reason);
/* records in block/level */
int (*get_minrecs)(struct xfs_btree_cur *cur, int level);
int (*get_maxrecs)(struct xfs_btree_cur *cur, int level);
/* records on disk. Matter for the root in inode case. */
int (*get_dmaxrecs)(struct xfs_btree_cur *cur, int level);
/* init values of btree structures */
void (*init_key_from_rec)(union xfs_btree_key *key,
const union xfs_btree_rec *rec);
void (*init_rec_from_cur)(struct xfs_btree_cur *cur,
union xfs_btree_rec *rec);
void (*init_ptr_from_cur)(struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr);
void (*init_high_key_from_rec)(union xfs_btree_key *key,
const union xfs_btree_rec *rec);
/* difference between key value and cursor value */
int64_t (*key_diff)(struct xfs_btree_cur *cur,
const union xfs_btree_key *key);
/*
* Difference between key2 and key1 -- positive if key1 > key2,
* negative if key1 < key2, and zero if equal. If the @mask parameter
* is non NULL, each key field to be used in the comparison must
* contain a nonzero value.
*/
int64_t (*diff_two_keys)(struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2,
const union xfs_btree_key *mask);
const struct xfs_buf_ops *buf_ops;
/* check that k1 is lower than k2 */
int (*keys_inorder)(struct xfs_btree_cur *cur,
const union xfs_btree_key *k1,
const union xfs_btree_key *k2);
/* check that r1 is lower than r2 */
int (*recs_inorder)(struct xfs_btree_cur *cur,
const union xfs_btree_rec *r1,
const union xfs_btree_rec *r2);
/*
* Are these two btree keys immediately adjacent?
*
* Given two btree keys @key1 and @key2, decide if it is impossible for
* there to be a third btree key K satisfying the relationship
* @key1 < K < @key2. To determine if two btree records are
* immediately adjacent, @key1 should be the high key of the first
* record and @key2 should be the low key of the second record.
* If the @mask parameter is non NULL, each key field to be used in the
* comparison must contain a nonzero value.
*/
enum xbtree_key_contig (*keys_contiguous)(struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2,
const union xfs_btree_key *mask);
};
/* btree geometry flags */
#define XFS_BTGEO_LASTREC_UPDATE (1U << 0) /* track last rec externally */
#define XFS_BTGEO_OVERLAPPING (1U << 1) /* overlapping intervals */
/*
* Reasons for the update_lastrec method to be called.
*/
#define LASTREC_UPDATE 0
#define LASTREC_INSREC 1
#define LASTREC_DELREC 2
union xfs_btree_irec {
struct xfs_alloc_rec_incore a;
struct xfs_bmbt_irec b;
struct xfs_inobt_rec_incore i;
struct xfs_rmap_irec r;
struct xfs_refcount_irec rc;
};
struct xfs_btree_level {
/* buffer pointer */
struct xfs_buf *bp;
/* key/record number */
uint16_t ptr;
/* readahead info */
#define XFS_BTCUR_LEFTRA (1 << 0) /* left sibling has been read-ahead */
#define XFS_BTCUR_RIGHTRA (1 << 1) /* right sibling has been read-ahead */
uint16_t ra;
};
/*
* Btree cursor structure.
* This collects all information needed by the btree code in one place.
*/
struct xfs_btree_cur
{
struct xfs_trans *bc_tp; /* transaction we're in, if any */
struct xfs_mount *bc_mp; /* file system mount struct */
const struct xfs_btree_ops *bc_ops;
struct kmem_cache *bc_cache; /* cursor cache */
unsigned int bc_flags; /* btree features - below */
union xfs_btree_irec bc_rec; /* current insert/search record value */
uint8_t bc_nlevels; /* number of levels in the tree */
uint8_t bc_maxlevels; /* maximum levels for this btree type */
/* per-type information */
union {
struct {
struct xfs_inode *ip;
short forksize;
char whichfork;
struct xbtree_ifakeroot *ifake; /* for staging cursor */
} bc_ino;
struct {
struct xfs_perag *pag;
struct xfs_buf *agbp;
struct xbtree_afakeroot *afake; /* for staging cursor */
} bc_ag;
struct {
struct xfbtree *xfbtree;
struct xfs_perag *pag;
} bc_mem;
};
/* per-format private data */
union {
struct {
int allocated;
} bc_bmap; /* bmapbt */
struct {
unsigned int nr_ops; /* # record updates */
unsigned int shape_changes; /* # of extent splits */
} bc_refc; /* refcountbt */
};
/* Must be at the end of the struct! */
struct xfs_btree_level bc_levels[];
};
/*
* Compute the size of a btree cursor that can handle a btree of a given
* height. The bc_levels array handles node and leaf blocks, so its size
* is exactly nlevels.
*/
static inline size_t
xfs_btree_cur_sizeof(unsigned int nlevels)
{
return struct_size_t(struct xfs_btree_cur, bc_levels, nlevels);
}
/* cursor state flags */
/*
* The root of this btree is a fakeroot structure so that we can stage a btree
* rebuild without leaving it accessible via primary metadata. The ops struct
* is dynamically allocated and must be freed when the cursor is deleted.
*/
#define XFS_BTREE_STAGING (1U << 0)
/* We are converting a delalloc reservation (only for bmbt btrees) */
#define XFS_BTREE_BMBT_WASDEL (1U << 1)
/* For extent swap, ignore owner check in verifier (only for bmbt btrees) */
#define XFS_BTREE_BMBT_INVALID_OWNER (1U << 2)
/* Cursor is active (only for allocbt btrees) */
#define XFS_BTREE_ALLOCBT_ACTIVE (1U << 3)
#define XFS_BTREE_NOERROR 0
#define XFS_BTREE_ERROR 1
/*
* Convert from buffer to btree block header.
*/
#define XFS_BUF_TO_BLOCK(bp) ((struct xfs_btree_block *)((bp)->b_addr))
xfs_failaddr_t __xfs_btree_check_block(struct xfs_btree_cur *cur,
struct xfs_btree_block *block, int level, struct xfs_buf *bp);
int __xfs_btree_check_ptr(struct xfs_btree_cur *cur,
const union xfs_btree_ptr *ptr, int index, int level);
/*
* Check that block header is ok.
*/
int
xfs_btree_check_block(
struct xfs_btree_cur *cur, /* btree cursor */
struct xfs_btree_block *block, /* generic btree block pointer */
int level, /* level of the btree block */
struct xfs_buf *bp); /* buffer containing block, if any */
/*
* Delete the btree cursor.
*/
void
xfs_btree_del_cursor(
struct xfs_btree_cur *cur, /* btree cursor */
int error); /* del because of error */
/*
* Duplicate the btree cursor.
* Allocate a new one, copy the record, re-get the buffers.
*/
int /* error */
xfs_btree_dup_cursor(
struct xfs_btree_cur *cur, /* input cursor */
struct xfs_btree_cur **ncur);/* output cursor */
/*
* Compute first and last byte offsets for the fields given.
* Interprets the offsets table, which contains struct field offsets.
*/
void
xfs_btree_offsets(
uint32_t fields, /* bitmask of fields */
const short *offsets,/* table of field offsets */
int nbits, /* number of bits to inspect */
int *first, /* output: first byte offset */
int *last); /* output: last byte offset */
/*
* Initialise a new btree block header
*/
void xfs_btree_init_buf(struct xfs_mount *mp, struct xfs_buf *bp,
const struct xfs_btree_ops *ops, __u16 level, __u16 numrecs,
__u64 owner);
void xfs_btree_init_block(struct xfs_mount *mp,
struct xfs_btree_block *buf, const struct xfs_btree_ops *ops,
__u16 level, __u16 numrecs, __u64 owner);
/*
* Common btree core entry points.
*/
int xfs_btree_increment(struct xfs_btree_cur *, int, int *);
int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *);
int xfs_btree_insert(struct xfs_btree_cur *, int *);
int xfs_btree_delete(struct xfs_btree_cur *, int *);
int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *);
int xfs_btree_change_owner(struct xfs_btree_cur *cur, uint64_t new_owner,
struct list_head *buffer_list);
/*
* btree block CRC helpers
*/
void xfs_btree_fsblock_calc_crc(struct xfs_buf *);
bool xfs_btree_fsblock_verify_crc(struct xfs_buf *);
void xfs_btree_agblock_calc_crc(struct xfs_buf *);
bool xfs_btree_agblock_verify_crc(struct xfs_buf *);
/*
* Internal btree helpers also used by xfs_bmap.c.
*/
void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, uint32_t);
void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int);
/*
* Helpers.
*/
static inline int xfs_btree_get_numrecs(const struct xfs_btree_block *block)
{
return be16_to_cpu(block->bb_numrecs);
}
static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
uint16_t numrecs)
{
block->bb_numrecs = cpu_to_be16(numrecs);
}
static inline int xfs_btree_get_level(const struct xfs_btree_block *block)
{
return be16_to_cpu(block->bb_level);
}
/*
* Min and max functions for extlen, agblock, fileoff, and filblks types.
*/
#define XFS_EXTLEN_MIN(a,b) min_t(xfs_extlen_t, (a), (b))
#define XFS_EXTLEN_MAX(a,b) max_t(xfs_extlen_t, (a), (b))
#define XFS_AGBLOCK_MIN(a,b) min_t(xfs_agblock_t, (a), (b))
#define XFS_AGBLOCK_MAX(a,b) max_t(xfs_agblock_t, (a), (b))
#define XFS_FILEOFF_MIN(a,b) min_t(xfs_fileoff_t, (a), (b))
#define XFS_FILEOFF_MAX(a,b) max_t(xfs_fileoff_t, (a), (b))
#define XFS_FILBLKS_MIN(a,b) min_t(xfs_filblks_t, (a), (b))
#define XFS_FILBLKS_MAX(a,b) max_t(xfs_filblks_t, (a), (b))
xfs_failaddr_t xfs_btree_agblock_v5hdr_verify(struct xfs_buf *bp);
xfs_failaddr_t xfs_btree_agblock_verify(struct xfs_buf *bp,
unsigned int max_recs);
xfs_failaddr_t xfs_btree_fsblock_v5hdr_verify(struct xfs_buf *bp,
uint64_t owner);
xfs_failaddr_t xfs_btree_fsblock_verify(struct xfs_buf *bp,
unsigned int max_recs);
xfs_failaddr_t xfs_btree_memblock_verify(struct xfs_buf *bp,
unsigned int max_recs);
unsigned int xfs_btree_compute_maxlevels(const unsigned int *limits,
unsigned long long records);
unsigned long long xfs_btree_calc_size(const unsigned int *limits,
unsigned long long records);
unsigned int xfs_btree_space_to_height(const unsigned int *limits,
unsigned long long blocks);
/*
* Return codes for the query range iterator function are 0 to continue
* iterating, and non-zero to stop iterating. Any non-zero value will be
* passed up to the _query_range caller. The special value -ECANCELED can be
* used to stop iteration, because _query_range never generates that error
* code on its own.
*/
typedef int (*xfs_btree_query_range_fn)(struct xfs_btree_cur *cur,
const union xfs_btree_rec *rec, void *priv);
int xfs_btree_query_range(struct xfs_btree_cur *cur,
const union xfs_btree_irec *low_rec,
const union xfs_btree_irec *high_rec,
xfs_btree_query_range_fn fn, void *priv);
int xfs_btree_query_all(struct xfs_btree_cur *cur, xfs_btree_query_range_fn fn,
void *priv);
typedef int (*xfs_btree_visit_blocks_fn)(struct xfs_btree_cur *cur, int level,
void *data);
/* Visit record blocks. */
#define XFS_BTREE_VISIT_RECORDS (1 << 0)
/* Visit leaf blocks. */
#define XFS_BTREE_VISIT_LEAVES (1 << 1)
/* Visit all blocks. */
#define XFS_BTREE_VISIT_ALL (XFS_BTREE_VISIT_RECORDS | \
XFS_BTREE_VISIT_LEAVES)
int xfs_btree_visit_blocks(struct xfs_btree_cur *cur,
xfs_btree_visit_blocks_fn fn, unsigned int flags, void *data);
int xfs_btree_count_blocks(struct xfs_btree_cur *cur, xfs_extlen_t *blocks);
union xfs_btree_rec *xfs_btree_rec_addr(struct xfs_btree_cur *cur, int n,
struct xfs_btree_block *block);
union xfs_btree_key *xfs_btree_key_addr(struct xfs_btree_cur *cur, int n,
struct xfs_btree_block *block);
union xfs_btree_key *xfs_btree_high_key_addr(struct xfs_btree_cur *cur, int n,
struct xfs_btree_block *block);
union xfs_btree_ptr *xfs_btree_ptr_addr(struct xfs_btree_cur *cur, int n,
struct xfs_btree_block *block);
int xfs_btree_lookup_get_block(struct xfs_btree_cur *cur, int level,
const union xfs_btree_ptr *pp, struct xfs_btree_block **blkp);
struct xfs_btree_block *xfs_btree_get_block(struct xfs_btree_cur *cur,
int level, struct xfs_buf **bpp);
bool xfs_btree_ptr_is_null(struct xfs_btree_cur *cur,
const union xfs_btree_ptr *ptr);
int64_t xfs_btree_diff_two_ptrs(struct xfs_btree_cur *cur,
const union xfs_btree_ptr *a,
const union xfs_btree_ptr *b);
void xfs_btree_get_sibling(struct xfs_btree_cur *cur,
struct xfs_btree_block *block,
union xfs_btree_ptr *ptr, int lr);
void xfs_btree_get_keys(struct xfs_btree_cur *cur,
struct xfs_btree_block *block, union xfs_btree_key *key);
union xfs_btree_key *xfs_btree_high_key_from_key(struct xfs_btree_cur *cur,
union xfs_btree_key *key);
typedef bool (*xfs_btree_key_gap_fn)(struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2);
int xfs_btree_has_records(struct xfs_btree_cur *cur,
const union xfs_btree_irec *low,
const union xfs_btree_irec *high,
const union xfs_btree_key *mask,
enum xbtree_recpacking *outcome);
bool xfs_btree_has_more_records(struct xfs_btree_cur *cur);
struct xfs_ifork *xfs_btree_ifork_ptr(struct xfs_btree_cur *cur);
/* Key comparison helpers */
static inline bool
xfs_btree_keycmp_lt(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2)
{
return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) < 0;
}
static inline bool
xfs_btree_keycmp_gt(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2)
{
return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) > 0;
}
static inline bool
xfs_btree_keycmp_eq(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2)
{
return cur->bc_ops->diff_two_keys(cur, key1, key2, NULL) == 0;
}
static inline bool
xfs_btree_keycmp_le(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2)
{
return !xfs_btree_keycmp_gt(cur, key1, key2);
}
static inline bool
xfs_btree_keycmp_ge(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2)
{
return !xfs_btree_keycmp_lt(cur, key1, key2);
}
static inline bool
xfs_btree_keycmp_ne(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2)
{
return !xfs_btree_keycmp_eq(cur, key1, key2);
}
/* Masked key comparison helpers */
static inline bool
xfs_btree_masked_keycmp_lt(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2,
const union xfs_btree_key *mask)
{
return cur->bc_ops->diff_two_keys(cur, key1, key2, mask) < 0;
}
static inline bool
xfs_btree_masked_keycmp_gt(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2,
const union xfs_btree_key *mask)
{
return cur->bc_ops->diff_two_keys(cur, key1, key2, mask) > 0;
}
static inline bool
xfs_btree_masked_keycmp_ge(
struct xfs_btree_cur *cur,
const union xfs_btree_key *key1,
const union xfs_btree_key *key2,
const union xfs_btree_key *mask)
{
return !xfs_btree_masked_keycmp_lt(cur, key1, key2, mask);
}
/* Does this cursor point to the last block in the given level? */
static inline bool
xfs_btree_islastblock(
struct xfs_btree_cur *cur,
int level)
{
struct xfs_btree_block *block;
struct xfs_buf *bp;
block = xfs_btree_get_block(cur, level, &bp);
if (cur->bc_ops->ptr_len == XFS_BTREE_LONG_PTR_LEN)
return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
}
void xfs_btree_set_ptr_null(struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr);
int xfs_btree_get_buf_block(struct xfs_btree_cur *cur,
const union xfs_btree_ptr *ptr, struct xfs_btree_block **block,
struct xfs_buf **bpp);
int xfs_btree_read_buf_block(struct xfs_btree_cur *cur,
const union xfs_btree_ptr *ptr, int flags,
struct xfs_btree_block **block, struct xfs_buf **bpp);
void xfs_btree_set_sibling(struct xfs_btree_cur *cur,
struct xfs_btree_block *block, const union xfs_btree_ptr *ptr,
int lr);
void xfs_btree_init_block_cur(struct xfs_btree_cur *cur,
struct xfs_buf *bp, int level, int numrecs);
void xfs_btree_copy_ptrs(struct xfs_btree_cur *cur,
union xfs_btree_ptr *dst_ptr,
const union xfs_btree_ptr *src_ptr, int numptrs);
void xfs_btree_copy_keys(struct xfs_btree_cur *cur,
union xfs_btree_key *dst_key,
const union xfs_btree_key *src_key, int numkeys);
void xfs_btree_init_ptr_from_cur(struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr);
static inline struct xfs_btree_cur *
xfs_btree_alloc_cursor(
struct xfs_mount *mp,
struct xfs_trans *tp,
const struct xfs_btree_ops *ops,
uint8_t maxlevels,
struct kmem_cache *cache)
{
struct xfs_btree_cur *cur;
ASSERT(ops->ptr_len == XFS_BTREE_LONG_PTR_LEN ||
ops->ptr_len == XFS_BTREE_SHORT_PTR_LEN);
/* BMBT allocations can come through from non-transactional context. */
cur = kmem_cache_zalloc(cache,
GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
cur->bc_ops = ops;
cur->bc_tp = tp;
cur->bc_mp = mp;
cur->bc_maxlevels = maxlevels;
cur->bc_cache = cache;
return cur;
}
int __init xfs_btree_init_cur_caches(void);
void xfs_btree_destroy_cur_caches(void);
int xfs_btree_goto_left_edge(struct xfs_btree_cur *cur);
/* Does this level of the cursor point to the inode root (and not a block)? */
static inline bool
xfs_btree_at_iroot(
const struct xfs_btree_cur *cur,
int level)
{
return cur->bc_ops->type == XFS_BTREE_TYPE_INODE &&
level == cur->bc_nlevels - 1;
}
#endif /* __XFS_BTREE_H__ */