/*      $NetBSD: chfs.h,v 1.11 2021/12/07 21:37:37 andvar Exp $ */

/*-
 * Copyright (c) 2010 Department of Software Engineering,
 *                    University of Szeged, Hungary
 * Copyright (C) 2009 Ferenc Havasi <havasi@inf.u-szeged.hu>
 * Copyright (C) 2009 Zoltan Sogor <weth@inf.u-szeged.hu>
 * Copyright (C) 2009 David Tengeri <dtengeri@inf.u-szeged.hu>
 * Copyright (C) 2009 Tamas Toth <ttoth@inf.u-szeged.hu>
 * Copyright (C) 2010 Adam Hoka <ahoka@NetBSD.org>
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by the Department of Software Engineering, University of Szeged, Hungary
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef __CHFS_H__
#define __CHFS_H__


#ifdef _KERNEL

#if 0
#define DBG_MSG                 /* debug messages */
#define DBG_MSG_GC              /* garbage collector's debug messages */
#endif

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/cdefs.h>
#include <sys/stdint.h>
#include <sys/types.h>
#include <sys/tree.h>
#include <sys/queue.h>
#include <sys/kmem.h>
#include <sys/endian.h>
#include <sys/rwlock.h>
#include <sys/condvar.h>
#include <sys/mutex.h>
#include <sys/kthread.h>
#include <sys/rbtree.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/hash.h>
#include <sys/module.h>
#include <sys/dirent.h>

#include <ufs/ufs/quota.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/dir.h>

/* XXX shouldnt be defined here, but needed by chfs_inode.h */
TAILQ_HEAD(chfs_dirent_list, chfs_dirent);

#include "chfs_pool.h"
#endif /* _KERNEL */

#include "ebh.h"
#include "media.h"
#include "chfs_inode.h"

/* padding - last two bits used for node masks */
#define CHFS_PAD(x) (((x)+3)&~3)

#ifdef _KERNEL

#ifndef MOUNT_CHFS
#define MOUNT_CHFS "chfs"
#endif /* MOUNT_CHFS */

/* state of a vnode */
enum {
        VNO_STATE_UNCHECKED,            /* CRC checks not yet done */
        VNO_STATE_CHECKING,                     /* CRC checks in progress */
        VNO_STATE_PRESENT,                      /* In core */
        VNO_STATE_CHECKEDABSENT,        /* Checked, cleared again */
        VNO_STATE_GC,                           /* GCing a 'pristine' node */
        VNO_STATE_READING,                      /* In read_inode() */
        VNO_STATE_CLEARING                      /* In clear_inode() */
};


/* size of the vnode cache (hashtable) */
#define VNODECACHE_SIZE 128

#define MAX_READ_FREE(chmp) (((chmp)->chm_ebh)->eb_size / 8)
/* an eraseblock will be clean if its dirty size is smaller than this */
#define MAX_DIRTY_TO_CLEAN 255
#define VERY_DIRTY(chmp, size) ((size) >= (((chmp)->chm_ebh)->eb_size / 2))

/* node errors */
enum {
        CHFS_NODE_OK = 0,
        CHFS_NODE_BADMAGIC,
        CHFS_NODE_BADCRC,
        CHFS_NODE_BADNAMECRC
};

/* eraseblock states */
enum {
        CHFS_BLK_STATE_FREE = 100,
        CHFS_BLK_STATE_CLEAN,
        CHFS_BLK_STATE_PARTDIRTY,
        CHFS_BLK_STATE_ALLDIRTY
};

extern struct pool chfs_inode_pool;
extern const struct genfs_ops chfs_genfsops;

/* struct chfs_node_ref - a reference to a node which is on the media */
struct chfs_node_ref
{
        struct chfs_node_ref *nref_next;        /* next data node which belongs to the same vnode */
        uint32_t nref_lnr;                                      /* nref's LEB number */
        uint32_t nref_offset;                           /* nref's offset */
};

/*
 * constants for allocating node refs 
 * they're allocated in blocks
 */
#define REFS_BLOCK_LEN (255/sizeof(struct chfs_node_ref))
#define REF_EMPTY_NODE (UINT_MAX)
#define REF_LINK_TO_NEXT (UINT_MAX - 1)

/* node masks - last two bits of the nodes ("state" of an nref) */
enum {
        CHFS_NORMAL_NODE_MASK,
        CHFS_UNCHECKED_NODE_MASK,
        CHFS_OBSOLETE_NODE_MASK,
        CHFS_PRISTINE_NODE_MASK
};

#define CHFS_REF_FLAGS(ref)             ((ref)->nref_offset & 3)
#define CHFS_REF_OBSOLETE(ref)  (((ref)->nref_offset & 3) == CHFS_OBSOLETE_NODE_MASK)
#define CHFS_MARK_REF_NORMAL(ref)                                             \
        do {                                                                  \
                (ref)->nref_offset = CHFS_GET_OFS((ref)->nref_offset) | CHFS_NORMAL_NODE_MASK; \
        } while(0)

#define CHFS_GET_OFS(ofs) (ofs & ~ 3)

/*
 * Nrefs are allocated in blocks, get the (in-memory) next. Usually the next
 * doesn't belongs to the same vnode.
 */
static __inline struct chfs_node_ref *
node_next(struct chfs_node_ref *nref)
{
        /* step to the next nref in the same block */
        nref++;

        /* REF_LINK_TO_NEXT means that the next node will be in the next block */
        if (nref->nref_lnr == REF_LINK_TO_NEXT) {
                nref = nref->nref_next;
                if (!nref)
                        return nref;
        }

        /* REF_EMPTY_NODE means that this is the last node */
        if (nref->nref_lnr == REF_EMPTY_NODE) {
                return NULL;
        }

        return nref;
}

/* struct chfs_dirent - full representation of a directory entry */
struct chfs_dirent
{
        struct chfs_node_ref *nref;             /* nref of the dirent */
        TAILQ_ENTRY(chfs_dirent) fds;   /* directory entries */
        uint64_t version;                               /* version */
        ino_t vno;                                              /* vnode number */
        uint32_t nhash;                                 /* name hash */
        enum chtype type;                               /* type of the dirent */
        uint8_t  nsize;                                 /* length of its name */
        uint8_t  name[0];                               /* name of the directory */
};

/* struct chfs_tmp_dnode - used temporarily while building a data node */
struct chfs_tmp_dnode {
        struct chfs_full_dnode *node;   /* associated full dnode */
        uint64_t version;                               /* version of the tmp node */
        uint32_t data_crc;                              /* CRC of the data */
        uint16_t overlapped;                    /* is overlapped */
        struct chfs_tmp_dnode *next;    /* next tmp node */
};

/* struct chfs_tmp_dnode_info - tmp nodes are stored in rb trees */
struct chfs_tmp_dnode_info {
        struct rb_node rb_node;                 /* rb tree entry */
        struct chfs_tmp_dnode *tmpnode; /* associated tmp node */
};

/* struct chfs_readinode_info - collection of tmp_dnodes */
struct chfs_readinode_info {
        struct rb_tree tdi_root;                                /* root of the rb tree */
        struct chfs_tmp_dnode_info *mdata_tn;   /* metadata (eg: symlink) */
        uint64_t highest_version;                               /* highest version of the nodes */
        struct chfs_node_ref *latest_ref;               /* latest node reference */
};

/* struct chfs_full_dnode - full data node */
struct chfs_full_dnode {
        struct chfs_node_ref *nref;             /* nref of the node */
        uint64_t ofs;                                   /* offset of the data node */
        uint32_t size;                                  /* size of the data node */
        uint32_t frags;                                 /* number of fragmentations */
};

/* struct chfs_node_frag - a fragment of a data node */
struct chfs_node_frag {
        struct rb_node rb_node;                 /* rb tree entry */
        struct chfs_full_dnode *node;   /* associated full dnode */
        uint32_t size;                                  /* size of the fragment */
        uint64_t ofs;                                   /* offset of the fragment */
};

/* find the first fragment of a data node */
static __inline struct chfs_node_frag *
frag_first(struct rb_tree *tree)
{
        struct chfs_node_frag *frag;

        frag = (struct chfs_node_frag *)RB_TREE_MIN(tree);

        return frag;
}

/* find the last fragment of a data node */
static __inline struct chfs_node_frag *
frag_last(struct rb_tree *tree)
{
        struct chfs_node_frag *frag;

        frag = (struct chfs_node_frag *)RB_TREE_MAX(tree);

        return frag;
}

/* iterate the fragtree */
#define frag_next(tree, frag) (struct chfs_node_frag *)rb_tree_iterate(tree, frag, RB_DIR_RIGHT)
#define frag_prev(tree, frag) (struct chfs_node_frag *)rb_tree_iterate(tree, frag, RB_DIR_LEFT)


/* struct chfs_vnode_cache - in memory representation of a file or directory */
struct chfs_vnode_cache {
        /* 
         * void *p must be the first field of the structure
         * but I can't remember where we use it and exactly for what
         */
        void *p;
        struct chfs_dirent_list scan_dirents;   /* used during scanning */

        struct chfs_node_ref *v;                        /* list of node informations */
        struct chfs_node_ref *dnode;            /* list of data nodes */
        struct chfs_node_ref *dirents;          /* list of directory entries */

        uint64_t *vno_version;                          /* version of the vnode */
        uint64_t highest_version;                       /* highest version of dnodes */

        uint8_t flags;                                          /* flags */
        uint16_t state;                                         /* actual state */
        ino_t vno;                                                      /* vnode number */
        ino_t pvno;                                                     /* vnode number of parent */
        struct chfs_vnode_cache* next;          /* next element of vnode cache */
        uint32_t nlink;                                         /* number of links to the file */
};

/* struct chfs_eraseblock - representation of an eraseblock */
struct chfs_eraseblock
{
        uint32_t lnr;           /* LEB number of the block*/

        TAILQ_ENTRY(chfs_eraseblock) queue;     /* queue entry */

        uint32_t unchecked_size;                        /* GC doesn't checked yet */
        uint32_t used_size;                                     /* size of nodes */
        uint32_t dirty_size;                            /* size of obsoleted nodes */
        uint32_t free_size;                                     /* available size */
        uint32_t wasted_size;                           /* paddings */

        struct chfs_node_ref *first_node;       /* first node of the block */
        struct chfs_node_ref *last_node;        /* last node of the block */

        struct chfs_node_ref *gc_node;          /* next node from the block 
                                                                                   which isn't garbage collected yet */
};

/* eraseblock queue */
TAILQ_HEAD(chfs_eraseblock_queue, chfs_eraseblock);

/* space allocation types */
#define ALLOC_NORMAL    0       /* allocating for normal usage (write, etc.) */
#define ALLOC_DELETION  1       /* allocating for deletion */
#define ALLOC_GC        2       /* allocating for the GC */

/* struct garbage_collector_thread - descriptor of GC thread */
struct garbage_collector_thread {
        lwp_t *gcth_thread;
        kcondvar_t gcth_wakeup;
        bool gcth_running;
};

/* states of mounting */
#define CHFS_MP_FLAG_SCANNING 2
#define CHFS_MP_FLAG_BUILDING 4

/* struct chfs_mount - CHFS main descriptor structure */
struct chfs_mount {
        struct mount *chm_fsmp;         /* general mount descriptor */
        struct chfs_ebh *chm_ebh;       /* eraseblock handler */
        int chm_fs_version;                     /* version of the FS */
        uint64_t chm_gbl_version;       /* */
        ino_t chm_max_vno;                      /* maximum of vnode numbers */
        ino_t chm_checked_vno;          /* vnode number of the last checked node */
        unsigned int chm_flags;         /* filesystem flags */

        /* 
         * chm_lock_mountfields:
         * Used to protect all the following fields.
         */
        kmutex_t chm_lock_mountfields;

        struct chfs_vnode_cache **chm_vnocache_hash;    /* hash table 
                                                                                                           of vnode caches */

        /* 
         * chm_lock_vnocache:
         * Used to protect the vnode cache.
         * If you have to lock chm_lock_mountfields and also chm_lock_vnocache,
         * you must lock chm_lock_mountfields first.
         */
        kmutex_t chm_lock_vnocache;

        struct chfs_eraseblock *chm_blocks;             /* list of eraseblocks */

        struct chfs_node *chm_root;             /* root node */

        uint32_t chm_free_size;                 /* available space */
        uint32_t chm_dirty_size;                /* size of contained obsoleted nodes */
        uint32_t chm_unchecked_size;    /* GC doesn't checked yet */
        uint32_t chm_used_size;                 /* size of contained nodes */
        uint32_t chm_wasted_size;               /* padding */

        /*
         * chm_lock_sizes:
         * Used to protect the (free, used, etc.) sizes of the FS
         * (and also the sizes of each eraseblock).
         * If you have to lock chm_lock_mountfields and also chm_lock_sizes,
         * you must lock chm_lock_mountfields first.
         */
        kmutex_t chm_lock_sizes;

        /*
         * eraseblock queues
         * free: completely free
         * clean: contains only valid data
         * dirty: contains valid and deleted data
         * very_dirty: contains mostly deleted data (should be GC'd)
         * erasable: doesn't contain valid data (should be erased)
         * erase_pending: we can erase blocks from this queue
         */
        struct chfs_eraseblock_queue chm_free_queue;
        struct chfs_eraseblock_queue chm_clean_queue;
        struct chfs_eraseblock_queue chm_dirty_queue;
        struct chfs_eraseblock_queue chm_very_dirty_queue;
        struct chfs_eraseblock_queue chm_erasable_pending_wbuf_queue;
        struct chfs_eraseblock_queue chm_erase_pending_queue;

        /* reserved blocks */
        uint8_t chm_resv_blocks_deletion;
        uint8_t chm_resv_blocks_write;
        uint8_t chm_resv_blocks_gctrigger;
        uint8_t chm_resv_blocks_gcmerge;
        uint8_t chm_nospc_dirty;

        uint8_t chm_vdirty_blocks_gctrigger;    /* GC trigger if the filesystem is
                                                                                           very dirty */

        struct chfs_eraseblock *chm_nextblock;  /* next block for usage */

        struct garbage_collector_thread chm_gc_thread;  /* descriptor of 
                                                                                                           GC thread */
        struct chfs_eraseblock *chm_gcblock;    /* next block for GC */

        int chm_nr_free_blocks;         /* number of free blocks */
        int chm_nr_erasable_blocks;     /* number of eraseable blocks */

        /* FS constants, used during writing */
        int32_t chm_fs_bmask;
        int32_t chm_fs_bsize;
        int32_t chm_fs_qbmask;
        int32_t chm_fs_bshift;
        int32_t chm_fs_fmask;
        int64_t chm_fs_qfmask;

        /* TODO will we use these? */
        unsigned int            chm_pages_max;
        unsigned int            chm_pages_used;
        struct chfs_pool        chm_dirent_pool;
        struct chfs_pool        chm_node_pool;
        struct chfs_str_pool    chm_str_pool;
        /**/

        size_t chm_wbuf_pagesize;       /* writebuffer's size */
        unsigned char* chm_wbuf;        /* writebuffer */
        size_t chm_wbuf_ofs;            /* actual offset of writebuffer */
        size_t chm_wbuf_len;            /* actual length of writebuffer */

        /*
         * chm_lock_wbuf:
         * Used to protect the write buffer.
         * If you have to lock chm_lock_mountfields and also chm_lock_wbuf,
         * you must lock chm_lock_mountfields first.
         */
        krwlock_t chm_lock_wbuf;
};

/*
 * TODO we should move here all of these from the bottom of the file
 * Macros/functions to convert from generic data structures to chfs
 * specific ones.
 */

/* directory entry offsets */
#define CHFS_OFFSET_DOT         0       /* this */
#define CHFS_OFFSET_DOTDOT      1       /* parent */
#define CHFS_OFFSET_EOF         2       /* after last */
#define CHFS_OFFSET_FIRST       3       /* first */


/*---------------------------------------------------------------------------*/

/* chfs_build.c */
void chfs_calc_trigger_levels(struct chfs_mount *);
int chfs_build_filesystem(struct chfs_mount *);
void chfs_build_set_vnodecache_nlink(struct chfs_mount *,
    struct chfs_vnode_cache *);
void chfs_build_remove_unlinked_vnode(struct chfs_mount *,
    struct chfs_vnode_cache *, struct chfs_dirent_list *);

/* chfs_scan.c */
int chfs_scan_eraseblock(struct chfs_mount *, struct chfs_eraseblock *);
struct chfs_vnode_cache *chfs_scan_make_vnode_cache(struct chfs_mount *,
    ino_t);
int chfs_scan_check_node_hdr(struct chfs_flash_node_hdr *);
int chfs_scan_check_vnode(struct chfs_mount *,
    struct chfs_eraseblock *, void *, off_t);
int chfs_scan_mark_dirent_obsolete(struct chfs_mount *,
    struct chfs_vnode_cache *, struct chfs_dirent *);
void chfs_add_fd_to_list(struct chfs_mount *,
    struct chfs_dirent *, struct chfs_vnode_cache *);
int chfs_scan_check_dirent_node(struct chfs_mount *,
    struct chfs_eraseblock *, void *, off_t);
int chfs_scan_check_data_node(struct chfs_mount *,
    struct chfs_eraseblock *, void *, off_t);
int chfs_scan_classify_cheb(struct chfs_mount *,
    struct chfs_eraseblock *);

/* chfs_nodeops.c */
int chfs_update_eb_dirty(struct chfs_mount *,
    struct chfs_eraseblock *, uint32_t);
void chfs_add_node_to_list(struct chfs_mount *, struct chfs_vnode_cache *,
    struct chfs_node_ref *, struct chfs_node_ref **);
void chfs_remove_node_from_list(struct chfs_mount *, struct chfs_vnode_cache *,
    struct chfs_node_ref *, struct chfs_node_ref **);
void chfs_remove_and_obsolete(struct chfs_mount *, struct chfs_vnode_cache *,
    struct chfs_node_ref *, struct chfs_node_ref **);
void chfs_add_fd_to_inode(struct chfs_mount *,
    struct chfs_inode *, struct chfs_dirent *);
void chfs_add_vnode_ref_to_vc(struct chfs_mount *, struct chfs_vnode_cache *,
    struct chfs_node_ref *);
struct chfs_node_ref* chfs_nref_next(struct chfs_node_ref *);
int chfs_nref_len(struct chfs_mount *,
    struct chfs_eraseblock *, struct chfs_node_ref *);
int chfs_close_eraseblock(struct chfs_mount *,
    struct chfs_eraseblock *);
int chfs_reserve_space_normal(struct chfs_mount *, uint32_t, int);
int chfs_reserve_space_gc(struct chfs_mount *, uint32_t);
int chfs_reserve_space(struct chfs_mount *, uint32_t);
void chfs_mark_node_obsolete(struct chfs_mount *, struct chfs_node_ref *);

/*
 * Find out the corresponding vnode cache from an nref.
 * Every last element of a linked list of nrefs is the vnode cache.
 */
static __inline struct chfs_vnode_cache *
chfs_nref_to_vc(struct chfs_node_ref *nref)
{
        /* iterate the whole list */
        while (nref->nref_next) {
                nref = nref->nref_next;
                if (nref->nref_lnr == REF_LINK_TO_NEXT) {
                        dbg("Link to next!\n");
                } else if (nref->nref_lnr == REF_EMPTY_NODE) {
                        dbg("Empty!\n");
                }
        }

        struct chfs_vnode_cache *vc = (struct chfs_vnode_cache *) nref;
        dbg("vno: %ju, pvno: %ju, hv: %ju, nlink: %u\n", (intmax_t )vc->vno,
            (intmax_t )vc->pvno, (intmax_t )vc->highest_version, vc->nlink);
        return vc;
}


/* chfs_malloc.c */
int chfs_alloc_pool_caches(void);
void chfs_destroy_pool_caches(void);
struct chfs_vnode_cache* chfs_vnode_cache_alloc(ino_t);
void chfs_vnode_cache_free(struct chfs_vnode_cache *);
struct chfs_node_ref* chfs_alloc_node_ref(
        struct chfs_eraseblock *);
void chfs_free_node_refs(struct chfs_eraseblock *);
struct chfs_dirent* chfs_alloc_dirent(int);
void chfs_free_dirent(struct chfs_dirent *);
struct chfs_flash_vnode* chfs_alloc_flash_vnode(void);
void chfs_free_flash_vnode(struct chfs_flash_vnode *);
struct chfs_flash_dirent_node* chfs_alloc_flash_dirent(void);
void chfs_free_flash_dirent(struct chfs_flash_dirent_node *);
struct chfs_flash_data_node* chfs_alloc_flash_dnode(void);
void chfs_free_flash_dnode(struct chfs_flash_data_node *);
struct chfs_node_frag* chfs_alloc_node_frag(void);
void chfs_free_node_frag(struct chfs_node_frag *);
struct chfs_node_ref* chfs_alloc_refblock(void);
void chfs_free_refblock(struct chfs_node_ref *);
struct chfs_full_dnode* chfs_alloc_full_dnode(void);
void chfs_free_full_dnode(struct chfs_full_dnode *);
struct chfs_tmp_dnode * chfs_alloc_tmp_dnode(void);
void chfs_free_tmp_dnode(struct chfs_tmp_dnode *);
struct chfs_tmp_dnode_info * chfs_alloc_tmp_dnode_info(void);
void chfs_free_tmp_dnode_info(struct chfs_tmp_dnode_info *);

/* chfs_readinode.c */
int chfs_read_inode(struct chfs_mount *, struct chfs_inode *);
int chfs_read_inode_internal(struct chfs_mount *, struct chfs_inode *);
void chfs_remove_frags_of_node(struct chfs_mount *, struct rb_tree *,
        struct chfs_node_ref *);
void chfs_kill_fragtree(struct chfs_mount *, struct rb_tree *);
uint32_t chfs_truncate_fragtree(struct chfs_mount *,
        struct rb_tree *, uint32_t);
int chfs_add_full_dnode_to_inode(struct chfs_mount *,
    struct chfs_inode *,
    struct chfs_full_dnode *);
int chfs_read_data(struct chfs_mount*, struct vnode *,
    struct buf *);

/* chfs_erase.c */
int chfs_remap_leb(struct chfs_mount *);

/* chfs_gc.c */
void chfs_gc_trigger(struct chfs_mount *);
int chfs_gc_thread_should_wake(struct chfs_mount *);
void chfs_gc_thread(void *);
void chfs_gc_thread_start(struct chfs_mount *);
void chfs_gc_thread_stop(struct chfs_mount *);
int chfs_gcollect_pass(struct chfs_mount *);

/* chfs_vfsops.c*/
int chfs_gop_alloc(struct vnode *, off_t, off_t,  int, kauth_cred_t);
int chfs_mountfs(struct vnode *, struct mount *);

/* chfs_vnops.c */
extern int (**chfs_vnodeop_p)(void *);
extern int (**chfs_specop_p)(void *);
extern int (**chfs_fifoop_p)(void *);
int chfs_lookup(void *);
int chfs_create(void *);
int chfs_mknod(void *);
int chfs_open(void *);
int chfs_close(void *);
int chfs_access(void *);
int chfs_getattr(void *);
int chfs_setattr(void *);
int chfs_chown(struct vnode *, uid_t, gid_t, kauth_cred_t);
int chfs_chmod(struct vnode *, int, kauth_cred_t);
int chfs_read(void *);
int chfs_write(void *);
int chfs_fsync(void *);
int chfs_remove(void *);
int chfs_link(void *);
int chfs_rename(void *);
int chfs_mkdir(void *);
int chfs_rmdir(void *);
int chfs_symlink(void *);
int chfs_readdir(void *);
int chfs_readlink(void *);
int chfs_inactive(void *);
int chfs_reclaim(void *);
int chfs_advlock(void *);
int chfs_strategy(void *);
int chfs_bmap(void *);

/* chfs_vnode.c */
struct vnode *chfs_vnode_lookup(struct chfs_mount *, ino_t);
int chfs_readvnode(struct mount *, ino_t, struct vnode **);
int chfs_readdirent(struct mount *, struct chfs_node_ref *,
    struct chfs_inode *);
int chfs_makeinode(int, struct vnode *, struct vnode **,
    struct componentname *, enum vtype );
void chfs_set_vnode_size(struct vnode *, size_t);
void chfs_change_size_free(struct chfs_mount *,
        struct chfs_eraseblock *, int);
void chfs_change_size_dirty(struct chfs_mount *,
        struct chfs_eraseblock *, int);
void chfs_change_size_unchecked(struct chfs_mount *,
        struct chfs_eraseblock *, int);
void chfs_change_size_used(struct chfs_mount *,
        struct chfs_eraseblock *, int);
void chfs_change_size_wasted(struct chfs_mount *,
        struct chfs_eraseblock *, int);

/* chfs_vnode_cache.c */
struct chfs_vnode_cache **chfs_vnocache_hash_init(void);
void chfs_vnocache_hash_destroy(struct chfs_vnode_cache **);
struct chfs_vnode_cache* chfs_vnode_cache_get(struct chfs_mount *, ino_t);
void chfs_vnode_cache_add(struct chfs_mount *, struct chfs_vnode_cache *);
void chfs_vnode_cache_remove(struct chfs_mount *, struct chfs_vnode_cache *);

/* chfs_wbuf.c */
int chfs_write_wbuf(struct chfs_mount*,
    const struct iovec *, long, off_t, size_t *);
int chfs_flush_pending_wbuf(struct chfs_mount *);

/* chfs_write.c */
int chfs_write_flash_vnode(struct chfs_mount *, struct chfs_inode *, int);
int chfs_write_flash_dirent(struct chfs_mount *, struct chfs_inode *,
    struct chfs_inode *, struct chfs_dirent *, ino_t, int);
int chfs_write_flash_dnode(struct chfs_mount *, struct vnode *,
    struct buf *, struct chfs_full_dnode *);
int chfs_do_link(struct chfs_inode *,
    struct chfs_inode *, const char *, int, enum chtype);
int chfs_do_unlink(struct chfs_inode *,
    struct chfs_inode *, const char *, int);

/* chfs_subr.c */
size_t chfs_mem_info(bool);
struct chfs_dirent * chfs_dir_lookup(struct chfs_inode *,
    struct componentname *);
int chfs_filldir (struct uio *, ino_t, const char *, int, enum chtype);
int chfs_chsize(struct vnode *, u_quad_t, kauth_cred_t);
int chfs_chflags(struct vnode *, int, kauth_cred_t);
void chfs_itimes(struct chfs_inode *, const struct timespec *,
    const struct timespec *, const struct timespec *);
int     chfs_update(struct vnode *, const struct timespec *,
    const struct timespec *, int);

/*---------------------------------------------------------------------------*/

/* Some inline functions temporarily placed here */

/* chfs_map_leb - corresponds to ebh_map_leb */
static __inline int
chfs_map_leb(struct chfs_mount *chmp, int lnr)
{
        int err;

        err = ebh_map_leb(chmp->chm_ebh, lnr);
        if (err)
                chfs_err("unmap leb %d failed, error: %d\n",lnr, err);

        return err;

}

/* chfs_unmap_leb - corresponds to ebh_unmap_leb */
static __inline int
chfs_unmap_leb(struct chfs_mount *chmp, int lnr)
{
        int err;

        err = ebh_unmap_leb(chmp->chm_ebh, lnr);
        if (err)
                chfs_err("unmap leb %d failed, error: %d\n",lnr, err);

        return err;
}

/* chfs_read_leb - corresponds to ebh_read_leb */
static __inline int
chfs_read_leb(struct chfs_mount *chmp, int lnr, char *buf,
    int offset, int len, size_t *retlen)
{
        int err;

        err = ebh_read_leb(chmp->chm_ebh, lnr, buf, offset, len, retlen);
        if (err)
                chfs_err("read leb %d:%d failed, error: %d\n",
                    lnr, offset, err);

        return err;
}

/* chfs_write_leb - corresponds to ebh_write_leb */
static __inline int chfs_write_leb(struct chfs_mount *chmp, int lnr, char *buf,
    int offset, int len, size_t *retlen)
{
        int err;
        err = ebh_write_leb(chmp->chm_ebh, lnr, buf, offset, len, retlen);
        if (err)
                chfs_err("write leb %d:%d failed, error: %d\n",
                    lnr, offset, err);

        return err;
}

/* --------------------------------------------------------------------- */

#define CHFS_PAGES_RESERVED (4 * 1024 * 1024 / PAGE_SIZE)

static __inline size_t
CHFS_PAGES_MAX(struct chfs_mount *chmp)
{
        size_t freepages;

        freepages = chfs_mem_info(false);
        if (freepages < CHFS_PAGES_RESERVED)
                freepages = 0;
        else
                freepages -= CHFS_PAGES_RESERVED;

        return MIN(chmp->chm_pages_max, freepages + chmp->chm_pages_used);
}

#define CHFS_ITIMES(ip, acc, mod, cre)                                \
        while ((ip)->iflag & (IN_ACCESS | IN_CHANGE | IN_UPDATE | IN_MODIFY)) \
                chfs_itimes(ip, acc, mod, cre)

/* used for KASSERTs */
#define IMPLIES(a, b) (!(a) || (b))
#define IFF(a, b) (IMPLIES(a, b) && IMPLIES(b, a))

#endif /* _KERNEL */
#endif /* __CHFS_H__ */