/* 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);

/*
 * Flags for xfs_alloc_fix_freelist.
 */
#define XFS_ALLOC_FLAG_TRYLOCK  (1U << 0)  /* use trylock for buffer locking */
#define XFS_ALLOC_FLAG_FREEING  (1U << 1)  /* indicate caller is freeing extents*/
#define XFS_ALLOC_FLAG_NORMAP   (1U << 2)  /* don't modify the rmapbt */
#define XFS_ALLOC_FLAG_NOSHRINK (1U << 3)  /* don't shrink the freelist */
#define XFS_ALLOC_FLAG_CHECK    (1U << 4)  /* test only, don't modify args */
#define XFS_ALLOC_FLAG_TRYFLUSH (1U << 5)  /* don't wait in busy extent flush */

/*
 * 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 */
        int             datatype;       /* mask defining data type treatment */
        char            wasdel;         /* set if allocation was prev delayed */
        char            wasfromfl;      /* set if allocation is from freelist */
        bool            alloc_minlen_only; /* allocate exact minlen extent */
        struct xfs_owner_info   oinfo;  /* owner of blocks being allocated */
        enum xfs_ag_resv_type   resv;   /* block reservation to use */
} 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);
int xfs_alloc_get_freelist(struct xfs_perag *pag, struct xfs_trans *tp,
                struct xfs_buf *agfbp, xfs_agblock_t *bnop, int  btreeblk);
int xfs_alloc_put_freelist(struct xfs_perag *pag, struct xfs_trans *tp,
                struct xfs_buf *agfbp, struct xfs_buf *agflbp,
                xfs_agblock_t bno, int btreeblk);
int xfs_free_ag_extent(struct xfs_trans *tp, struct xfs_buf *agbp,
                xfs_agblock_t bno, xfs_extlen_t len,
                const struct xfs_owner_info *oinfo, enum xfs_ag_resv_type type);

/*
 * Compute and fill in value of m_alloc_maxlevels.
 */
void
xfs_alloc_compute_maxlevels(
        struct xfs_mount        *mp);   /* file system mount structure */

/*
 * 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 */
        uint32_t        fields);/* mask of fields to be logged (XFS_AGF_...) */

/*
 * Allocate an extent anywhere in the specific AG given. If there is no
 * space matching the requirements in that AG, then the allocation will fail.
 */
int xfs_alloc_vextent_this_ag(struct xfs_alloc_arg *args, xfs_agnumber_t agno);

/*
 * Allocate an extent as close to the target as possible. If there are not
 * viable candidates in the AG, then fail the allocation.
 */
int xfs_alloc_vextent_near_bno(struct xfs_alloc_arg *args,
                xfs_fsblock_t target);

/*
 * Allocate an extent exactly at the target given. If this is not possible
 * then the allocation fails.
 */
int xfs_alloc_vextent_exact_bno(struct xfs_alloc_arg *args,
                xfs_fsblock_t target);

/*
 * Best effort full filesystem allocation scan.
 *
 * Locality aware allocation will be attempted in the initial AG, but on failure
 * non-localised attempts will be made. The AGs are constrained by previous
 * allocations in the current transaction. Two passes will be made - the first
 * non-blocking, the second blocking.
 */
int xfs_alloc_vextent_start_ag(struct xfs_alloc_arg *args,
                xfs_fsblock_t target);

/*
 * Iterate from the AG indicated from args->fsbno through to the end of the
 * filesystem attempting blocking allocation. This is for use in last
 * resort allocation attempts when everything else has failed.
 */
int xfs_alloc_vextent_first_ag(struct xfs_alloc_arg *args,
                xfs_fsblock_t target);

/*
 * Free an extent.
 */
int                             /* error */
__xfs_free_extent(
        struct xfs_trans        *tp,    /* transaction pointer */
        struct xfs_perag        *pag,
        xfs_agblock_t           agbno,
        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,
        struct xfs_perag        *pag,
        xfs_agblock_t           agbno,
        xfs_extlen_t            len,
        const struct xfs_owner_info     *oinfo,
        enum xfs_ag_resv_type   type)
{
        return __xfs_free_extent(tp, pag, agbno, 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 */

union xfs_btree_rec;
void xfs_alloc_btrec_to_irec(const union xfs_btree_rec *rec,
                struct xfs_alloc_rec_incore *irec);
xfs_failaddr_t xfs_alloc_check_irec(struct xfs_perag *pag,
                const struct xfs_alloc_rec_incore *irec);

int xfs_read_agf(struct xfs_perag *pag, struct xfs_trans *tp, int flags,
                struct xfs_buf **agfbpp);
int xfs_alloc_read_agf(struct xfs_perag *pag, struct xfs_trans *tp, int flags,
                struct xfs_buf **agfbpp);
int xfs_alloc_read_agfl(struct xfs_perag *pag, struct xfs_trans *tp,
                struct xfs_buf **bpp);
int xfs_alloc_fix_freelist(struct xfs_alloc_arg *args, uint32_t alloc_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_records(struct xfs_btree_cur *cur, xfs_agblock_t bno,
                xfs_extlen_t len, enum xbtree_recpacking *outcome);

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;
}

int xfs_free_extent_later(struct xfs_trans *tp, xfs_fsblock_t bno,
                xfs_filblks_t len, const struct xfs_owner_info *oinfo,
                enum xfs_ag_resv_type type, unsigned int free_flags);

/* Don't issue a discard for the blocks freed. */
#define XFS_FREE_EXTENT_SKIP_DISCARD    (1U << 0)

/* Free blocks on the realtime device. */
#define XFS_FREE_EXTENT_REALTIME        (1U << 1)

#define XFS_FREE_EXTENT_ALL_FLAGS       (XFS_FREE_EXTENT_SKIP_DISCARD | \
                                         XFS_FREE_EXTENT_REALTIME)

/*
 * 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 */
        struct xfs_group        *xefi_group;
        unsigned int            xefi_flags;
        enum xfs_ag_resv_type   xefi_agresv;
};

#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 */
#define XFS_EFI_CANCELLED       (1U << 3) /* dont actually free the space */
#define XFS_EFI_REALTIME        (1U << 4) /* freeing realtime extent */

static inline bool xfs_efi_is_realtime(const struct xfs_extent_free_item *xefi)
{
        return xefi->xefi_flags & XFS_EFI_REALTIME;
}

struct xfs_alloc_autoreap {
        struct xfs_defer_pending        *dfp;
};

int xfs_alloc_schedule_autoreap(const struct xfs_alloc_arg *args,
                unsigned int free_flags, struct xfs_alloc_autoreap *aarp);
void xfs_alloc_cancel_autoreap(struct xfs_trans *tp,
                struct xfs_alloc_autoreap *aarp);
void xfs_alloc_commit_autoreap(struct xfs_trans *tp,
                struct xfs_alloc_autoreap *aarp);

extern struct kmem_cache        *xfs_extfree_item_cache;

int __init xfs_extfree_intent_init_cache(void);
void xfs_extfree_intent_destroy_cache(void);

xfs_failaddr_t xfs_validate_ag_length(struct xfs_buf *bp, uint32_t seqno,
                uint32_t length);

#endif  /* __XFS_ALLOC_H__ */