linux/fs/xfs/libxfs/xfs_alloc.h
Darrick J. Wong 93defd5a15 xfs: document the XFS_ALLOC_AGFL_RESERVE constant
Currently, we use this undocumented macro to encode the minimum number
of blocks needed to replenish a completely empty AGFL when an AG is
nearly full.  This has lead to confusion on the part of the maintainers,
so let's document what the value actually means, and move it to
xfs_alloc.c since it's not used outside of that module.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-03-21 13:57:45 -07:00

287 lines
9.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#ifndef __XFS_ALLOC_H__
#define __XFS_ALLOC_H__
struct xfs_buf;
struct xfs_btree_cur;
struct xfs_mount;
struct xfs_perag;
struct xfs_trans;
extern struct workqueue_struct *xfs_alloc_wq;
unsigned int xfs_agfl_size(struct xfs_mount *mp);
/*
* Freespace allocation types. Argument to xfs_alloc_[v]extent.
*/
#define XFS_ALLOCTYPE_FIRST_AG 0x02 /* ... start at ag 0 */
#define XFS_ALLOCTYPE_THIS_AG 0x08 /* anywhere in this a.g. */
#define XFS_ALLOCTYPE_START_BNO 0x10 /* near this block else anywhere */
#define XFS_ALLOCTYPE_NEAR_BNO 0x20 /* in this a.g. and near this block */
#define XFS_ALLOCTYPE_THIS_BNO 0x40 /* at exactly this block */
/* this should become an enum again when the tracing code is fixed */
typedef unsigned int xfs_alloctype_t;
#define XFS_ALLOC_TYPES \
{ XFS_ALLOCTYPE_FIRST_AG, "FIRST_AG" }, \
{ XFS_ALLOCTYPE_THIS_AG, "THIS_AG" }, \
{ XFS_ALLOCTYPE_START_BNO, "START_BNO" }, \
{ XFS_ALLOCTYPE_NEAR_BNO, "NEAR_BNO" }, \
{ XFS_ALLOCTYPE_THIS_BNO, "THIS_BNO" }
/*
* Flags for xfs_alloc_fix_freelist.
*/
#define XFS_ALLOC_FLAG_TRYLOCK 0x00000001 /* use trylock for buffer locking */
#define XFS_ALLOC_FLAG_FREEING 0x00000002 /* indicate caller is freeing extents*/
#define XFS_ALLOC_FLAG_NORMAP 0x00000004 /* don't modify the rmapbt */
#define XFS_ALLOC_FLAG_NOSHRINK 0x00000008 /* don't shrink the freelist */
#define XFS_ALLOC_FLAG_CHECK 0x00000010 /* test only, don't modify args */
/*
* Argument structure for xfs_alloc routines.
* This is turned into a structure to avoid having 20 arguments passed
* down several levels of the stack.
*/
typedef struct xfs_alloc_arg {
struct xfs_trans *tp; /* transaction pointer */
struct xfs_mount *mp; /* file system mount point */
struct xfs_buf *agbp; /* buffer for a.g. freelist header */
struct xfs_perag *pag; /* per-ag struct for this agno */
xfs_fsblock_t fsbno; /* file system block number */
xfs_agnumber_t agno; /* allocation group number */
xfs_agblock_t agbno; /* allocation group-relative block # */
xfs_extlen_t minlen; /* minimum size of extent */
xfs_extlen_t maxlen; /* maximum size of extent */
xfs_extlen_t mod; /* mod value for extent size */
xfs_extlen_t prod; /* prod value for extent size */
xfs_extlen_t minleft; /* min blocks must be left after us */
xfs_extlen_t total; /* total blocks needed in xaction */
xfs_extlen_t alignment; /* align answer to multiple of this */
xfs_extlen_t minalignslop; /* slop for minlen+alignment calcs */
xfs_agblock_t min_agbno; /* set an agbno range for NEAR allocs */
xfs_agblock_t max_agbno; /* ... */
xfs_extlen_t len; /* output: actual size of extent */
xfs_alloctype_t type; /* allocation type XFS_ALLOCTYPE_... */
xfs_alloctype_t otype; /* original allocation type */
int datatype; /* mask defining data type treatment */
char wasdel; /* set if allocation was prev delayed */
char wasfromfl; /* set if allocation is from freelist */
struct xfs_owner_info oinfo; /* owner of blocks being allocated */
enum xfs_ag_resv_type resv; /* block reservation to use */
#ifdef DEBUG
bool alloc_minlen_only; /* allocate exact minlen extent */
#endif
} xfs_alloc_arg_t;
/*
* Defines for datatype
*/
#define XFS_ALLOC_USERDATA (1 << 0)/* allocation is for user data*/
#define XFS_ALLOC_INITIAL_USER_DATA (1 << 1)/* special case start of file */
#define XFS_ALLOC_NOBUSY (1 << 2)/* Busy extents not allowed */
/* freespace limit calculations */
unsigned int xfs_alloc_set_aside(struct xfs_mount *mp);
unsigned int xfs_alloc_ag_max_usable(struct xfs_mount *mp);
xfs_extlen_t xfs_alloc_longest_free_extent(struct xfs_perag *pag,
xfs_extlen_t need, xfs_extlen_t reserved);
unsigned int xfs_alloc_min_freelist(struct xfs_mount *mp,
struct xfs_perag *pag);
/*
* Compute and fill in value of m_alloc_maxlevels.
*/
void
xfs_alloc_compute_maxlevels(
struct xfs_mount *mp); /* file system mount structure */
/*
* Get a block from the freelist.
* Returns with the buffer for the block gotten.
*/
int /* error */
xfs_alloc_get_freelist(
struct xfs_trans *tp, /* transaction pointer */
struct xfs_buf *agbp, /* buffer containing the agf structure */
xfs_agblock_t *bnop, /* block address retrieved from freelist */
int btreeblk); /* destination is a AGF btree */
/*
* Log the given fields from the agf structure.
*/
void
xfs_alloc_log_agf(
struct xfs_trans *tp, /* transaction pointer */
struct xfs_buf *bp, /* buffer for a.g. freelist header */
int fields);/* mask of fields to be logged (XFS_AGF_...) */
/*
* Interface for inode allocation to force the pag data to be initialized.
*/
int /* error */
xfs_alloc_pagf_init(
struct xfs_mount *mp, /* file system mount structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
int flags); /* XFS_ALLOC_FLAGS_... */
/*
* Put the block on the freelist for the allocation group.
*/
int /* error */
xfs_alloc_put_freelist(
struct xfs_trans *tp, /* transaction pointer */
struct xfs_buf *agbp, /* buffer for a.g. freelist header */
struct xfs_buf *agflbp,/* buffer for a.g. free block array */
xfs_agblock_t bno, /* block being freed */
int btreeblk); /* owner was a AGF btree */
/*
* Read in the allocation group header (free/alloc section).
*/
int /* error */
xfs_alloc_read_agf(
struct xfs_mount *mp, /* mount point structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
int flags, /* XFS_ALLOC_FLAG_... */
struct xfs_buf **bpp); /* buffer for the ag freelist header */
/*
* Allocate an extent (variable-size).
*/
int /* error */
xfs_alloc_vextent(
xfs_alloc_arg_t *args); /* allocation argument structure */
/*
* Free an extent.
*/
int /* error */
__xfs_free_extent(
struct xfs_trans *tp, /* transaction pointer */
xfs_fsblock_t bno, /* starting block number of extent */
xfs_extlen_t len, /* length of extent */
const struct xfs_owner_info *oinfo, /* extent owner */
enum xfs_ag_resv_type type, /* block reservation type */
bool skip_discard);
static inline int
xfs_free_extent(
struct xfs_trans *tp,
xfs_fsblock_t bno,
xfs_extlen_t len,
const struct xfs_owner_info *oinfo,
enum xfs_ag_resv_type type)
{
return __xfs_free_extent(tp, bno, len, oinfo, type, false);
}
int /* error */
xfs_alloc_lookup_le(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
xfs_extlen_t len, /* length of extent */
int *stat); /* success/failure */
int /* error */
xfs_alloc_lookup_ge(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
xfs_extlen_t len, /* length of extent */
int *stat); /* success/failure */
int /* error */
xfs_alloc_get_rec(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t *bno, /* output: starting block of extent */
xfs_extlen_t *len, /* output: length of extent */
int *stat); /* output: success/failure */
int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,
xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);
int xfs_alloc_read_agfl(struct xfs_mount *mp, struct xfs_trans *tp,
xfs_agnumber_t agno, struct xfs_buf **bpp);
int xfs_free_agfl_block(struct xfs_trans *, xfs_agnumber_t, xfs_agblock_t,
struct xfs_buf *, struct xfs_owner_info *);
int xfs_alloc_fix_freelist(struct xfs_alloc_arg *args, int flags);
int xfs_free_extent_fix_freelist(struct xfs_trans *tp, struct xfs_perag *pag,
struct xfs_buf **agbp);
xfs_extlen_t xfs_prealloc_blocks(struct xfs_mount *mp);
typedef int (*xfs_alloc_query_range_fn)(
struct xfs_btree_cur *cur,
const struct xfs_alloc_rec_incore *rec,
void *priv);
int xfs_alloc_query_range(struct xfs_btree_cur *cur,
const struct xfs_alloc_rec_incore *low_rec,
const struct xfs_alloc_rec_incore *high_rec,
xfs_alloc_query_range_fn fn, void *priv);
int xfs_alloc_query_all(struct xfs_btree_cur *cur, xfs_alloc_query_range_fn fn,
void *priv);
int xfs_alloc_has_record(struct xfs_btree_cur *cur, xfs_agblock_t bno,
xfs_extlen_t len, bool *exist);
typedef int (*xfs_agfl_walk_fn)(struct xfs_mount *mp, xfs_agblock_t bno,
void *priv);
int xfs_agfl_walk(struct xfs_mount *mp, struct xfs_agf *agf,
struct xfs_buf *agflbp, xfs_agfl_walk_fn walk_fn, void *priv);
static inline __be32 *
xfs_buf_to_agfl_bno(
struct xfs_buf *bp)
{
if (xfs_has_crc(bp->b_mount))
return bp->b_addr + sizeof(struct xfs_agfl);
return bp->b_addr;
}
void __xfs_free_extent_later(struct xfs_trans *tp, xfs_fsblock_t bno,
xfs_filblks_t len, const struct xfs_owner_info *oinfo,
bool skip_discard);
/*
* List of extents to be free "later".
* The list is kept sorted on xbf_startblock.
*/
struct xfs_extent_free_item {
struct list_head xefi_list;
uint64_t xefi_owner;
xfs_fsblock_t xefi_startblock;/* starting fs block number */
xfs_extlen_t xefi_blockcount;/* number of blocks in extent */
unsigned int xefi_flags;
};
#define XFS_EFI_SKIP_DISCARD (1U << 0) /* don't issue discard */
#define XFS_EFI_ATTR_FORK (1U << 1) /* freeing attr fork block */
#define XFS_EFI_BMBT_BLOCK (1U << 2) /* freeing bmap btree block */
static inline void
xfs_free_extent_later(
struct xfs_trans *tp,
xfs_fsblock_t bno,
xfs_filblks_t len,
const struct xfs_owner_info *oinfo)
{
__xfs_free_extent_later(tp, bno, len, oinfo, false);
}
extern struct kmem_cache *xfs_extfree_item_cache;
int __init xfs_extfree_intent_init_cache(void);
void xfs_extfree_intent_destroy_cache(void);
#endif /* __XFS_ALLOC_H__ */