// TODO: CHECK/REPLACE/UPDATE OLD CODE (this file is based on xv6)
#include "sched.h"
#include "fsinstance.h"
#include "mkfs/fsformat.h"
#include "diskio.h"
struct context;
struct file;
struct pipe;
struct proc;
struct stat;
struct fsinstance;

#ifdef _ZCC
void __sync_synchronize();
#endif

void _entry(); // Only invoked at boot, indicates start of kernel image

// bio.c
void            binit(void);
diskio_buffer_t*     bread(uint, uint);
void            diskio_buffer_release(diskio_buffer_t*);
void            diskio_buffer_write(diskio_buffer_t*);
void            diskio_buffer_reference(diskio_buffer_t*);
void            diskio_buffer_dereference(diskio_buffer_t*);

// console.c
void            consoleinit(void);
void            consoleintr(int);
void            consputc(int);

// exec.c
int             execve(char*, char**, char**);

// file.c
struct file*    filealloc(void);
void            fileclose(struct file*);
struct file*    filedup(struct file*);
void            fileinit(void);
int             fileread(struct file*, uint64, int n);
int             filestat(struct file*, uint64 addr);
int             filewrite(struct file*, uint64, int n);

// fs.c
void*           fsinit(struct fsinstance*, unsigned int);
int             namecmp(const char*, const char*);

// ramdisk.c
void            ramdiskinit(void);
void            ramdiskintr(void);
void            ramdiskrw(diskio_buffer_t*);

// physpg.c
#define PHYSPG_FREERAM 1001
#define PHYSPG_METADATA 1002
#define PHYSPG_KALLOC 1003
void physpg_initbegin();
void physpg_initend();
uint64 physpg_freeram();
uint64 physpg_totalram();
void* physpg_alloc1(int mode);
void physpg_free1(int mode, void* physpg);
void physpg_setrange(int mode, void* start, void* end);
#define kalloc() physpg_alloc1(PHYSPG_KALLOC)
#define kfree(p) physpg_free1(PHYSPG_KALLOC,p)

// log.c
void            initlog(struct fsinstance*, int, fsformat_superblock_t*);

// pipe.c
int             pipealloc(struct file**, struct file**);
void            pipeclose(struct pipe*, int);
int             piperead(struct pipe*, uint64, int);
int             pipewrite(struct pipe*, uint64, int);

// proc.c
int             cpuid(void);
void            exit(int);
int             fork(void);
int             thrd(uint64 fnc, uint64 stk, uint64 arg);
int             affin(uint64 mask);
int             growproc(int);
void            proc_mapstacks(pagetable_t);
pagetable_t     proc_pagetable(struct proc *);
void            proc_freepagetable(pagetable_t, uint64, int);
int             kill(int);
int             killed(struct proc*);
void            setkilled(struct proc*);
struct proc*    myproc();
void            procinit(void);
#ifdef _ZCC
void            scheduler(void);
#else
void            scheduler(void) __attribute__((noreturn));
#endif
void            sched(void);
void            sleep(void*, sched_spinlock_t*);
void            userinit(void);
int             wait(uint64);
void            yield(void);
int             either_copyout(int user_dst, uint64 dst, void *src, uint64 len);
int             either_copyin(void *dst, int user_src, uint64 src, uint64 len);
void            procdump(void);

// swtch.S
void            swtch(struct context*, struct context*);

// spinlock.c
void            acquire(sched_spinlock_t*);
int             holding(sched_spinlock_t*);
void            initlock(sched_spinlock_t*, char*);
void            release(sched_spinlock_t*);
void            push_off(void);
void            pop_off(void);

// sleeplock.c
void            acquiresleep(sched_sleeplock_t*);
void            releasesleep(sched_sleeplock_t*);
int             holdingsleep(sched_sleeplock_t*);
void            initsleeplock(sched_sleeplock_t*, char*);

// string.c
int             memcmp(const void*, const void*, uint);
void*           memmove(void*, const void*, uint);
void*           memset(void*, int, unsigned long long);
char*           safestrcpy(char*, const char*, int);
int             strlen(const char*);
int             strncmp(const char*, const char*, uint);
char*           strncpy(char*, const char*, int);

// syscall.c
void            argint(int, int*);
int             argstr(int, char*, int);
void            argaddr(int, uint64 *);
int             fetchstr(uint64, char*, int);
int             fetchaddr(uint64, uint64*);
void            syscall();

// trap.c
extern uint     ticks;
void            trapinit(void);
void            trapinithart(void);
extern sched_spinlock_t tickslock;
void            usertrapret(void);

// uart.c
void            uartinit(void);
void            uartintr(void);
void            uartputc(int);
void            uartputc_sync(int);
int             uartgetc(void);

// vm.c
void            kvminit(void);
void            kvminithart(void);
void            kvmmap(pagetable_t, uint64, uint64, uint64, int);
int             mappages(pagetable_t, uint64, uint64, uint64, int);
pagetable_t     uvmcreate(void);
void            uvmfirst(pagetable_t, uchar *, uint);
uint64          uvmalloc(pagetable_t, uint64, uint64, int);
uint64          uvmdealloc(pagetable_t, uint64, uint64);
int             uvmcopy(pagetable_t, pagetable_t, uint64);
int             uvmcopyshallow(pagetable_t, pagetable_t, uint64);
void            uvmfree(pagetable_t, uint64, int);
void            uvmunmap(pagetable_t, uint64, uint64, int);
void            uvmclear(pagetable_t, uint64);
pte_t *         walk(pagetable_t, uint64, int);
uint64          walkaddr(pagetable_t, uint64);
int             copyout(pagetable_t, uint64, char *, uint64);
int             copyin(pagetable_t, char *, uint64, uint64);
int             copyinstr(pagetable_t, char *, uint64, uint64);

// plic.c
void            plicinit(void);
void            plicinithart(void);
int             plic_claim(void);
void            plic_complete(int);

// virtio_disk.c
void            virtio_disk_init(void);
void            virtio_disk_rw(diskio_buffer_t *, int);
void            virtio_disk_intr(void);

// number of elements in fixed-size array
#define NELEM(x) (sizeof(x)/sizeof((x)[0]))

extern char end[]; // first address after kernel.
                   // defined by kernel.ld.

#define MB (1024ULL*1024ULL)