/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * suballoc.h
 *
 * Defines sub allocator api
 *
 * Copyright (C) 2003, 2004 Oracle.  All rights reserved.
 */

#ifndef _CHAINALLOC_H_
#define _CHAINALLOC_H_

struct ocfs2_suballoc_result;
typedef int (group_search_t)(struct inode *,
                             struct buffer_head *,
                             u32,                       /* bits_wanted */
                             u32,                       /* min_bits */
                             u64,                       /* max_block */
                             struct ocfs2_suballoc_result *);
                                                        /* found bits */

struct ocfs2_alloc_context {
        struct inode *ac_inode;    /* which bitmap are we allocating from? */
        struct buffer_head *ac_bh; /* file entry bh */
        u32    ac_alloc_slot;   /* which slot are we allocating from? */
        u32    ac_bits_wanted;
        u32    ac_bits_given;
#define OCFS2_AC_USE_LOCAL 1
#define OCFS2_AC_USE_MAIN  2
#define OCFS2_AC_USE_INODE 3
#define OCFS2_AC_USE_META  4
#define OCFS2_AC_USE_MAIN_DISCONTIG  5
        u32    ac_which;

        /* these are used by the chain search */
        u16    ac_chain;
        int    ac_disable_chain_relink;
        group_search_t *ac_group_search;

        u64    ac_last_group;
        u64    ac_max_block;  /* Highest block number to allocate. 0 is
                                 the same as ~0 - unlimited */

        int    ac_find_loc_only;  /* hack for reflink operation ordering */
        struct ocfs2_suballoc_result *ac_find_loc_priv; /* */

        struct ocfs2_alloc_reservation  *ac_resv;
};

void ocfs2_init_steal_slots(struct ocfs2_super *osb);
void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
static inline int ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context *ac)
{
        return ac->ac_bits_wanted - ac->ac_bits_given;
}

/*
 * Please note that the caller must make sure that root_el is the root
 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
 * the result may be wrong.
 */
int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
                               struct ocfs2_extent_list *root_el,
                               struct ocfs2_alloc_context **ac);
int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
                                      int blocks,
                                      struct ocfs2_alloc_context **ac);
int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
                            struct ocfs2_alloc_context **ac);
int ocfs2_reserve_clusters(struct ocfs2_super *osb,
                           u32 bits_wanted,
                           struct ocfs2_alloc_context **ac);

int ocfs2_alloc_dinode_update_counts(struct inode *inode,
                         handle_t *handle,
                         struct buffer_head *di_bh,
                         u32 num_bits,
                         u16 chain);
void ocfs2_rollback_alloc_dinode_counts(struct inode *inode,
                         struct buffer_head *di_bh,
                         u32 num_bits,
                         u16 chain);
u16 ocfs2_find_max_contig_free_bits(void *bitmap,
                         u16 total_bits, u16 start);
int ocfs2_block_group_set_bits(handle_t *handle,
                         struct inode *alloc_inode,
                         struct ocfs2_group_desc *bg,
                         struct buffer_head *group_bh,
                         unsigned int bit_off,
                         unsigned int num_bits,
                         unsigned int max_contig_bits,
                         int fastpath);

int ocfs2_claim_metadata(handle_t *handle,
                         struct ocfs2_alloc_context *ac,
                         u32 bits_wanted,
                         u64 *suballoc_loc,
                         u16 *suballoc_bit_start,
                         u32 *num_bits,
                         u64 *blkno_start);
int ocfs2_claim_new_inode(handle_t *handle,
                          struct inode *dir,
                          struct buffer_head *parent_fe_bh,
                          struct ocfs2_alloc_context *ac,
                          u64 *suballoc_loc,
                          u16 *suballoc_bit,
                          u64 *fe_blkno);
int ocfs2_claim_clusters(handle_t *handle,
                         struct ocfs2_alloc_context *ac,
                         u32 min_clusters,
                         u32 *cluster_start,
                         u32 *num_clusters);
/*
 * Use this variant of ocfs2_claim_clusters to specify a maximum
 * number of clusters smaller than the allocation reserved.
 */
int __ocfs2_claim_clusters(handle_t *handle,
                           struct ocfs2_alloc_context *ac,
                           u32 min_clusters,
                           u32 max_clusters,
                           u32 *cluster_start,
                           u32 *num_clusters);

int ocfs2_free_suballoc_bits(handle_t *handle,
                             struct inode *alloc_inode,
                             struct buffer_head *alloc_bh,
                             unsigned int start_bit,
                             u64 bg_blkno,
                             unsigned int count);
int ocfs2_free_dinode(handle_t *handle,
                      struct inode *inode_alloc_inode,
                      struct buffer_head *inode_alloc_bh,
                      struct ocfs2_dinode *di);
int ocfs2_free_clusters(handle_t *handle,
                        struct inode *bitmap_inode,
                        struct buffer_head *bitmap_bh,
                        u64 start_blk,
                        unsigned int num_clusters);
int ocfs2_release_clusters(handle_t *handle,
                           struct inode *bitmap_inode,
                           struct buffer_head *bitmap_bh,
                           u64 start_blk,
                           unsigned int num_clusters);

static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
{
        u64 group = block - (u64) bit;

        return group;
}

static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
                                          u64 bg_blkno)
{
        /* This should work for all block group descriptors as only
         * the 1st group descriptor of the cluster bitmap is
         * different. */

        if (bg_blkno == osb->first_cluster_group_blkno)
                return 0;

        /* the rest of the block groups are located at the beginning
         * of their 1st cluster, so a direct translation just
         * works. */
        return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
}

static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
{
        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
        return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
}

/* This is for local alloc ONLY. Others should use the task-specific
 * apis above. */
int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
                                      struct ocfs2_alloc_context *ac);
void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);

/* given a cluster offset, calculate which block group it belongs to
 * and return that block offset. */
u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);

/*
 * By default, ocfs2_read_group_descriptor() calls ocfs2_error() when it
 * finds a problem.  A caller that wants to check a group descriptor
 * without going readonly should read the block with ocfs2_read_block[s]()
 * and then checking it with this function.  This is only resize, really.
 * Everyone else should be using ocfs2_read_group_descriptor().
 */
int ocfs2_check_group_descriptor(struct super_block *sb,
                                 struct ocfs2_dinode *di,
                                 struct buffer_head *bh);
/*
 * Read a group descriptor block into *bh.  If *bh is NULL, a bh will be
 * allocated.  This is a cached read.  The descriptor will be validated with
 * ocfs2_validate_group_descriptor().
 */
int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
                                u64 gd_blkno, struct buffer_head **bh);

int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
                          u32 clusters_to_add, u32 extents_to_split,
                          struct ocfs2_alloc_context **data_ac,
                          struct ocfs2_alloc_context **meta_ac);

int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res);



/*
 * The following two interfaces are for ocfs2_create_inode_in_orphan().
 */
int ocfs2_find_new_inode_loc(struct inode *dir,
                             struct buffer_head *parent_fe_bh,
                             struct ocfs2_alloc_context *ac,
                             u64 *fe_blkno);

int ocfs2_claim_new_inode_at_loc(handle_t *handle,
                                 struct inode *dir,
                                 struct ocfs2_alloc_context *ac,
                                 u64 *suballoc_loc,
                                 u16 *suballoc_bit,
                                 u64 di_blkno);

#endif /* _CHAINALLOC_H_ */