kernel.h

#pragma once

#include "common.h"

struct sbiret {
  long error;
  long value;
};

#define PANIC(fmt, ...)                                                        \
  do {                                                                         \
    printf("PANIC: %s:%d: " fmt "\n", __FILE__, __LINE__, ##__VA_ARGS__);      \
    while (1) {                                                                \
    }                                                                          \
  } while (0)

struct trap_frame {
  uint32_t ra;
  uint32_t gp;
  uint32_t tp;
  uint32_t t0;
  uint32_t t1;
  uint32_t t2;
  uint32_t t3;
  uint32_t t4;
  uint32_t t5;
  uint32_t t6;
  uint32_t a0;
  uint32_t a1;
  uint32_t a2;
  uint32_t a3;
  uint32_t a4;
  uint32_t a5;
  uint32_t a6;
  uint32_t a7;
  uint32_t s0;
  uint32_t s1;
  uint32_t s2;
  uint32_t s3;
  uint32_t s4;
  uint32_t s5;
  uint32_t s6;
  uint32_t s7;
  uint32_t s8;
  uint32_t s9;
  uint32_t s10;
  uint32_t s11;
  uint32_t sp;
} __attribute__((packed));

#define READ_CSR(reg)                                                          \
  ({                                                                           \
    unsigned long __tmp;                                                       \
    __asm__ __volatile__("csrr %0, " #reg : "=r"(__tmp));                      \
    __tmp;                                                                     \
  })

#define WRITE_CSR(reg, value)                                                  \
  do {                                                                         \
    uint32_t __tmp = (value);                                                  \
    __asm__ __volatile__("csrw " #reg ", %0" ::"r"(__tmp));                    \
  } while (0)

#define PROCS_MAX 8

#define PROC_UNUSED 0
#define PROC_RUNNABLE 1
#define PROC_EXITED 2

struct process {
  int pid;
  int state;
  vaddr_t sp;
  uint32_t *page_table;
  uint8_t stack[8192];
};

#define SATP_SV32 (1u << 31)
#define PAGE_V (1 << 0) // 有効化ビット
#define PAGE_R (1 << 1) // 読み込み可能
#define PAGE_W (1 << 2) // 書き込み可能
#define PAGE_X (1 << 3) // 実行可能
#define PAGE_U (1 << 4) // ユーザーモードでアクセス可能

#define USER_BASE 0x1000000
#define SSTATUS_SPIE (1 << 5)
#define SSTATUS_SUM (1 << 18)

#define SCAUSE_ECALL 8

#define SECTOR_SIZE 512
#define VIRTQ_ENTRY_NUM 16
#define VIRTIO_DEVICE_BLK 2
#define VIRTIO_BLK_PADDR 0x10001000
#define VIRTIO_REG_MAGIC 0x00
#define VIRTIO_REG_VERSION 0x04
#define VIRTIO_REG_DEVICE_ID 0x08
#define VIRTIO_REG_QUEUE_SEL 0x30
#define VIRTIO_REG_QUEUE_NUM_MAX 0x34
#define VIRTIO_REG_QUEUE_NUM 0x38
#define VIRTIO_REG_QUEUE_ALIGN 0x3c
#define VIRTIO_REG_QUEUE_PFN 0x40
#define VIRTIO_REG_QUEUE_READY 0x44
#define VIRTIO_REG_QUEUE_NOTIFY 0x50
#define VIRTIO_REG_DEVICE_STATUS 0x70
#define VIRTIO_REG_DEVICE_CONFIG 0x100
#define VIRTIO_STATUS_ACK 1
#define VIRTIO_STATUS_DRIVER 2
#define VIRTIO_STATUS_DRIVER_OK 4
#define VIRTIO_STATUS_FEAT_OK 8
#define VIRTQ_DESC_F_NEXT 1
#define VIRTQ_DESC_F_WRITE 2
#define VIRTQ_AVAIL_F_NO_INTERRUPT 1
#define VIRTIO_BLK_T_IN 0
#define VIRTIO_BLK_T_OUT 1

struct virtq_desc {
  uint64_t addr;
  uint32_t len;
  uint16_t flags;
  uint16_t next;
} __attribute__((packed));

struct virtq_avail {
  uint16_t flags;
  uint16_t index;
  uint16_t ring[VIRTQ_ENTRY_NUM];
} __attribute__((packed));

struct virtq_used_elem {
  uint32_t id;
  uint32_t len;
} __attribute__((packed));

struct virtq_used {
  uint16_t flags;
  uint16_t index;
  struct virtq_used_elem ring[VIRTQ_ENTRY_NUM];
} __attribute__((packed));

struct virtio_virtq {
  struct virtq_desc descs[VIRTQ_ENTRY_NUM];
  struct virtq_avail avail;
  struct virtq_used used __attribute__((aligned(PAGE_SIZE)));
  int queue_index;
  volatile uint16_t *used_index;
  uint16_t last_used_index;
} __attribute__((packed));

struct virtio_blk_req {
  uint32_t type;
  uint32_t reserved;
  uint64_t sector;
  uint8_t data[512];
  uint8_t status;
} __attribute__((packed));

#define FILES_MAX 2
#define DISK_MAX_SIZE align_up(sizeof(struct file) * FILES_MAX, SECTOR_SIZE)

struct tar_header {
  char name[100];
  char mode[8];
  char uid[8];
  char gid[8];
  char size[12];
  char mtime[12];
  char checksum[8];
  char type;
  char linkname[100];
  char magic[6];
  char version[2];
  char uname[32];
  char gname[32];
  char devmajor[8];
  char devminor[8];
  char prefix[155];
  char padding[12];
  char data[];
} __attribute__((packed));

struct file {
  bool in_use;
  char name[100];
  char data[1024];
  size_t size;
};