/* 将inode写入到分区part */
void inode_sync(struct partition* part, struct inode* inode, void* io_buf) { // io_buf是用于硬盘io的缓冲区
uint8_t inode_no = inode->i_no;
struct inode_position inode_pos;
inode_locate(part, inode_no, &inode_pos); // inode位置信息会存入inode_pos
ASSERT(inode_pos.sec_lba <= (part->start_lba + part->sec_cnt));
/* 硬盘中的inode中的成员inode_tag和i_open_cnts是不需要的,
* 它们只在内存中记录链表位置和被多少进程共享 */
struct inode pure_inode;
memcpy(&pure_inode, inode, sizeof(struct inode));
/* 以下inode的三个成员只存在于内存中,现在将inode同步到硬盘,清掉这三项即可 */
pure_inode.i_open_cnts = 0;
pure_inode.write_deny = false; // 置为false,以保证在硬盘中读出时为可写
pure_inode.inode_tag.prev = pure_inode.inode_tag.next = NULL;
char* inode_buf = (char*)io_buf;
if (inode_pos.two_sec) { // 若是跨了两个扇区,就要读出两个扇区再写入两个扇区
/* 读写硬盘是以扇区为单位,若写入的数据小于一扇区,要将原硬盘上的内容先读出来再和新数据拼成一扇区后再写入 */
ide_read(part->my_disk, inode_pos.sec_lba, inode_buf, 2); // inode在format中写入硬盘时是连续写入的,所以读入2块扇区
/* 开始将待写入的inode拼入到这2个扇区中的相应位置 */
memcpy((inode_buf + inode_pos.off_size), &pure_inode, sizeof(struct inode));
/* 将拼接好的数据再写入磁盘 */
ide_write(part->my_disk, inode_pos.sec_lba, inode_buf, 2);
} else { // 若只是一个扇区
ide_read(part->my_disk, inode_pos.sec_lba, inode_buf, 1);
memcpy((inode_buf + inode_pos.off_size), &pure_inode, sizeof(struct inode));
ide_write(part->my_disk, inode_pos.sec_lba, inode_buf, 1);
}
}
/* 在part分区内的pdir目录内寻找名为name的文件或目录,
* 找到后返回true并将其目录项存入dir_e,否则返回false */
bool search_dir_entry(struct partition* part, struct dir* pdir, \
const char* name, struct dir_entry* dir_e) {
uint32_t block_cnt = 140; // 12个直接块+128个一级间接块=140块
/* 12个直接块大小+128个间接块,共560字节 */
uint32_t* all_blocks = (uint32_t*)sys_malloc(48 + 512);
if (all_blocks == NULL) {
printk("search_dir_entry: sys_malloc for all_blocks failed");
return false;
}
uint32_t block_idx = 0;
while (block_idx < 12) {
all_blocks[block_idx] = pdir->inode->i_sectors[block_idx];
block_idx++;
}
block_idx = 0;
if (pdir->inode->i_sectors[12] != 0) { // 若含有一级间接块表
ide_read(part->my_disk, pdir->inode->i_sectors[12], all_blocks + 12, 1);
}
/* 至此,all_blocks存储的是该文件或目录的所有扇区地址 */
/* 写目录项的时候已保证目录项不跨扇区,
* 这样读目录项时容易处理, 只申请容纳1个扇区的内存 */
uint8_t* buf = (uint8_t*)sys_malloc(SECTOR_SIZE);
struct dir_entry* p_de = (struct dir_entry*)buf; // p_de为指向目录项的指针,值为buf起始地址
uint32_t dir_entry_size = part->sb->dir_entry_size;
uint32_t dir_entry_cnt = SECTOR_SIZE / dir_entry_size; // 1扇区内可容纳的目录项个数
/* 开始在所有块中查找目录项 */
while (block_idx < block_cnt) {
/* 块地址为0时表示该块中无数据,继续在其它块中找 */
if (all_blocks[block_idx] == 0) {
block_idx++;
continue;
}
ide_read(part->my_disk, all_blocks[block_idx], buf, 1);
uint32_t dir_entry_idx = 0;
/* 遍历扇区中所有目录项 */
while (dir_entry_idx < dir_entry_cnt) {
/* 若找到了,就直接复制整个目录项 */
if (!strcmp(p_de->filename, name)) {
memcpy(dir_e, p_de, dir_entry_size);
sys_free(buf);
sys_free(all_blocks);
return true;
}
dir_entry_idx++;
p_de++;
}
block_idx++;
p_de = (struct dir_entry*)buf; // 此时p_de已经指向扇区内最后一个完整目录项了,需要恢复p_de指向为buf
memset(buf, 0, SECTOR_SIZE); // 将buf清0,下次再用
}
sys_free(buf);
sys_free(all_blocks);
return false;
}
// Fault any disk block that is read or written in to memory by
// loading it from disk.
// Hint: Use ide_read and BLKSECTS.
static void
bc_pgfault(struct UTrapframe *utf)
{
void *addr = (void *) utf->utf_fault_va;
uint64_t blockno = ((uint64_t)addr - DISKMAP) / BLKSIZE;
int r;
// Check that the fault was within the block cache region
if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
panic("page fault in FS: eip %08x, va %08x, err %04x",
utf->utf_rip, addr, utf->utf_err);
// Sanity check the block number.
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
// Allocate a page in the disk map region, read the contents
// of the block from the disk into that page, and mark the
// page not-dirty (since reading the data from disk will mark
// the page dirty).
//
// LAB 5: Your code here
void *dst_addr = (void *) ROUNDDOWN(addr, BLKSIZE);
r = sys_page_alloc(thisenv->env_id, dst_addr, PTE_U | PTE_P | PTE_W);
// Project addition --> Transparent disk decryption (called only if disk block
// is encrypted). Bitmap block has been left out of encryption, bitmap block data is tightly
// bound in other routines, so can't encrypt.
if(blockno == 2)
ide_read(blockno * BLKSECTS, dst_addr, BLKSECTS);
else if (blockno == 1) /* || (blockno == 2)) */
{
if(!s_encrypted)
ide_read(blockno * BLKSECTS, dst_addr, BLKSECTS);
else
{
r = transparent_disk_decrypt(blockno, dst_addr);
if(r)
return;
}
}
else
{
r = transparent_disk_decrypt(blockno, dst_addr);
if(r)
return;
}
// panic("bc_pgfault not implemented");
// Check that the block we read was allocated. (exercise for
// the reader: why do we do this *after* reading the block
// in?)
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
}
void ide_delay(uint8_t channel)
{
/* Each call delays 100 ns */
ide_read(channel, IDE_REGISTER_STATUS);
ide_read(channel, IDE_REGISTER_STATUS);
ide_read(channel, IDE_REGISTER_STATUS);
ide_read(channel, IDE_REGISTER_STATUS);
}
uint32_t loader() {
Elf32_Ehdr *elf;
Elf32_Phdr *ph = NULL;
uint8_t buf[4096];
#ifdef HAS_DEVICE
ide_read(buf, ELF_OFFSET_IN_DISK, 4096);
#else
ramdisk_read(buf, ELF_OFFSET_IN_DISK, 4096);
#endif
elf = (void*)buf;
/* fix the magic number with the correct one */
const uint32_t elf_magic = 0x464c457f;
uint32_t *p_magic = (void *)buf;
nemu_assert(*p_magic == elf_magic);
/* Load each program segment */
int i;
for(i=0;i<elf->e_phnum;i++ ) {
/* Scan the program header table, load each segment into memory */
ph=(void *)(elf->e_phoff + i * elf->e_phentsize + buf);
if(ph->p_type == PT_LOAD) {
//Log("success");
#ifdef IA32_PAGE
/* Record the program break for future use. */
extern uint32_t brk;
uint32_t new_brk = ph->p_vaddr + ph->p_memsz - 1;
if(brk < new_brk) { brk = new_brk; }
uint32_t pa=mm_malloc(ph->p_vaddr,ph->p_memsz);
#endif
#ifndef HAS_DEVICE
ramdisk_read((void*)pa, ELF_OFFSET_IN_DISK + ph->p_offset, ph->p_filesz);
#else
ide_read((void*)pa, ELF_OFFSET_IN_DISK + ph->p_offset, ph->p_filesz);
#endif
memset((void*)(pa + ph->p_filesz), 0, ph->p_memsz - ph->p_filesz);
}
}
volatile uint32_t entry = elf->e_entry;
#ifdef IA32_PAGE
mm_malloc(KOFFSET - STACK_SIZE, STACK_SIZE);
#ifdef HAS_DEVICE
create_video_mapping();
#endif
write_cr3(get_ucr3());
#endif
return entry;
}
/* 在分区链表中找到名为part_name的分区,并将其指针赋值给cur_part */
static bool mount_partition(struct list_elem* pelem, int arg) {
char* part_name = (char*)arg;
struct partition* part = elem2entry(struct partition, part_tag, pelem);
if (!strcmp(part->name, part_name)) {
cur_part = part;
struct disk* hd = cur_part->my_disk;
/* sb_buf用来存储从硬盘上读入的超级块 */
struct super_block* sb_buf = (struct super_block*)sys_malloc(SECTOR_SIZE);
/* 在内存中创建分区cur_part的超级块 */
cur_part->sb = (struct super_block*)sys_malloc(sizeof(struct super_block));
if (cur_part->sb == NULL) {
PANIC("alloc memory failed!");
}
/* 读入超级块 */
memset(sb_buf, 0, SECTOR_SIZE);
ide_read(hd, cur_part->start_lba + 1, sb_buf, 1);
/* 把sb_buf中超级块的信息复制到分区的超级块sb中。*/
memcpy(cur_part->sb, sb_buf, sizeof(struct super_block));
/********** 将硬盘上的块位图读入到内存 ****************/
cur_part->block_bitmap.bits = (uint8_t*)sys_malloc(sb_buf->block_bitmap_sects * SECTOR_SIZE);
if (cur_part->block_bitmap.bits == NULL) {
PANIC("alloc memory failed!");
}
cur_part->block_bitmap.btmp_bytes_len = sb_buf->block_bitmap_sects * SECTOR_SIZE;
/* 从硬盘上读入块位图到分区的block_bitmap.bits */
ide_read(hd, sb_buf->block_bitmap_lba, cur_part->block_bitmap.bits, sb_buf->block_bitmap_sects);
/*************************************************************/
/********** 将硬盘上的inode位图读入到内存 ************/
cur_part->inode_bitmap.bits = (uint8_t*)sys_malloc(sb_buf->inode_bitmap_sects * SECTOR_SIZE);
if (cur_part->inode_bitmap.bits == NULL) {
PANIC("alloc memory failed!");
}
cur_part->inode_bitmap.btmp_bytes_len = sb_buf->inode_bitmap_sects * SECTOR_SIZE;
/* 从硬盘上读入inode位图到分区的inode_bitmap.bits */
ide_read(hd, sb_buf->inode_bitmap_lba, cur_part->inode_bitmap.bits, sb_buf->inode_bitmap_sects);
/*************************************************************/
list_init(&cur_part->open_inodes);
printk("mount %s done!\n", part->name);
/* 此处返回true是为了迎合主调函数list_traversal的实现,与函数本身功能无关。
只有返回true时list_traversal才会停止遍历,减少了后面元素无意义的遍历.*/
return true;
}
return false; // 使list_traversal继续遍历
}
int fs_read(int fd, void *buf, int len)
{
int i=fd;
if(file_state[i].offset+len>file_table[i-3].size)
{
int len_new=file_table[i-3].size-file_state[i].offset;
ide_read(buf,file_table[i-3].disk_offset+file_state[i].offset,len_new);
file_state[i].offset+=len_new;
return len_new;
}
ide_read(buf,file_table[i-3].disk_offset+file_state[i].offset,len);
file_state[i].offset+=len;
return len;
}
/* 根据i结点号返回相应的i结点 */
struct inode* inode_open(struct partition* part, uint32_t inode_no) {
/* 先在已打开inode链表中找inode,此链表是为提速创建的缓冲区 */
struct list_elem* elem = part->open_inodes.head.next;
struct inode* inode_found;
while (elem != &part->open_inodes.tail) {
inode_found = elem2entry(struct inode, inode_tag, elem);
if (inode_found->i_no == inode_no) {
inode_found->i_open_cnts++;
return inode_found;
}
elem = elem->next;
}
/*由于open_inodes链表中找不到,下面从硬盘上读入此inode并加入到此链表 */
struct inode_position inode_pos;
/* inode位置信息会存入inode_pos, 包括inode所在扇区地址和扇区内的字节偏移量 */
inode_locate(part, inode_no, &inode_pos);
/* 为使通过sys_malloc创建的新inode被所有任务共享,
* 需要将inode置于内核空间,故需要临时
* 将cur_pbc->pgdir置为NULL */
struct task_struct* cur = running_thread();
uint32_t* cur_pagedir_bak = cur->pgdir;
cur->pgdir = NULL;
/* 以上三行代码完成后下面分配的内存将位于内核区 */
inode_found = (struct inode*)sys_malloc(sizeof(struct inode));
/* 恢复pgdir */
cur->pgdir = cur_pagedir_bak;
char* inode_buf;
if (inode_pos.two_sec) { // 考虑跨扇区的情况
inode_buf = (char*)sys_malloc(1024);
/* i结点表是被partition_format函数连续写入扇区的,
* 所以下面可以连续读出来 */
ide_read(part->my_disk, inode_pos.sec_lba, inode_buf, 2);
} else { // 否则,所查找的inode未跨扇区,一个扇区大小的缓冲区足够
inode_buf = (char*)sys_malloc(512);
ide_read(part->my_disk, inode_pos.sec_lba, inode_buf, 1);
}
memcpy(inode_found, inode_buf + inode_pos.off_size, sizeof(struct inode));
/* 因为一会很可能要用到此inode,故将其插入到队首便于提前检索到 */
list_push(&part->open_inodes, &inode_found->inode_tag);
inode_found->i_open_cnts = 1;
sys_free(inode_buf);
return inode_found;
}
// Make sure a particular disk block is loaded into memory.
// Returns 0 on success, or a negative error code on error.
//
// If blk != 0, set *blk to the address of the block in memory.
//
// Hint: Use diskaddr, map_block, and ide_read.
static int
read_block(uint32_t blockno, char **blk)
{
int r;
char *addr;
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
addr = diskaddr(blockno);
if(!block_is_mapped(blockno)){
if((r = map_block(blockno)) < 0)
return r;
r = ide_read(blockno*BLKSECTS, (void *)addr, BLKSECTS);
if(r < 0)
return r;
}
if(blk)
*blk = addr;
return 0;
}
// Make sure a particular disk block is loaded into memory.
// Returns 0 on success, or a negative error code on error.
//
// If blk != 0, set *blk to the address of the block in memory.
//
// Hint: Use diskaddr, map_block, and ide_read.
static int
read_block(uint32_t blockno, char **blk)
{
int r;
char *addr;
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
// LAB 5: Your code here.
addr = diskaddr(blockno);
int error = map_block(blockno);
if(error<0) return error;
int secno = blockno*BLKSECTS;
error = ide_read(secno, addr, (size_t)BLKSECTS);
if(error) return error;
if(blk) *blk = addr;
// panic("read_block not implemented");
return 0;
}
// Make sure a particular disk block is loaded into memory.
// Returns 0 on success, or a negative error code on error.
//
// If blk != 0, set *blk to the address of the block in memory.
//
// Hint: Use diskaddr, map_block, and ide_read.
static int
read_block(uint32_t blockno, char **blk)
{
int r;
char *addr;
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
// LAB 5: Your code here.
addr = diskaddr(blockno);
if(!block_is_mapped(blockno)){
if ((r = sys_page_alloc(sys_getenvid(), diskaddr(blockno), PTE_U|PTE_P|PTE_W)) < 0)
return r;
if((r = ide_read(blockno*(BLKSIZE/SECTSIZE), addr, (size_t) BLKSIZE/SECTSIZE)) < 0)
return r;
}
if(blk != 0)
*blk = addr;
return 0;
}
// Make sure a particular disk block is loaded into memory.
// Returns 0 on success, or a negative error code on error.
//
// If blk != 0, set *blk to the address of the block in memory.
//
// Hint: Use diskaddr, map_block, and ide_read.
static int
read_block(uint32_t blockno, char **blk)
{
int r;
char *addr;
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
// LAB 5: Your code here.
addr = diskaddr(blockno);
if (block_is_mapped(blockno)) {
goto succeeded;
}
// now that the block is not in memory, allocate memory and read it in.
if ((r = map_block(blockno)) < 0)
return r;
if ((r = ide_read(blockno * BLKSECTS, addr, BLKSECTS)) < 0)
return r;
succeeded:
if (blk)
*blk = addr;
return 0;
}
// Make sure a particular disk block is loaded into memory.
// Returns 0 on success, or a negative error code on error.
//
// If blk != 0, set *blk to the address of the block in memory.
//
// Hint: Use diskaddr, map_block, and ide_read.
static int
read_block(uint32_t blockno, char **blk)
{
int r;
char *addr;
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
// LAB 5: Your code here.
r = map_block(blockno);
if (r)
return r;
addr = diskaddr(blockno);
r = ide_read(blockno * BLKSECTS, addr, BLKSECTS);
if (r)
return r;
if (blk)
*blk = addr;
return sys_page_map(0, addr, 0, addr, vpt[VPN(addr)] & PTE_USER);
}
// Fault any disk block that is read or written in to memory by
// loading it from disk.
// Hint: Use ide_read and BLKSECTS.
static void
bc_pgfault(struct UTrapframe *utf)
{
void *addr = (void *) utf->utf_fault_va;
uint32_t blockno = ((uint32_t)addr - DISKMAP) / BLKSIZE;
int r;
// Check that the fault was within the block cache region
if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
panic("page fault in FS: eip %08x, va %08x, err %04x",
utf->utf_eip, addr, utf->utf_err);
// Allocate a page in the disk map region and read the
// contents of the block from the disk into that page.
//
// LAB 5: Your code here
addr = ROUNDDOWN(addr, PGSIZE);
if ((r = sys_page_alloc(0, addr, PTE_USER)) < 0)
panic("sys_page_alloc: %e", r);
if (ide_read(blockno * BLKSECTS, addr, BLKSECTS) < 0)
panic("ide_read failed");
// Sanity check the block number. (exercise for the reader:
// why do we do this *after* reading the block in?)
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
// Check that the block we read was allocated.
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
}
/**
* \brief Lee 512 bytes de un dispositivo
* \param indexDevice
* \param block
* \param buffer
* \return 1, si todo Ok, 0 en caso contrario
*/
int ReadBlock(int indexDevice, unsigned block, unsigned char* buffer)
{
unsigned status,err;
if (!devices[indexDevice].existe) return 0;
// voy a leer con lba28
unsigned lba0 = block & 0xFF;
unsigned lba1 = (block & 0xFF00) >> 8;
unsigned lba2 = (block & 0xFF0000) >> 16;
unsigned devSelected = (block & 0xFF000000) >> 24;
devSelected = (devices[indexDevice].slave << 4) | devSelected | 0x40;
unsigned sectorCount = 1;
// espero a que este desocupado el dispositivo
while (ide_read(indexDevice, ATA_REG_STATUS) & ATA_SR_BSY);
// ahora a leer el sector en cuestion
ide_write(indexDevice,ATA_REG_SECCOUNT0, sectorCount);
ide_write(indexDevice,ATA_REG_LBA0, lba0);
ide_write(indexDevice,ATA_REG_LBA1, lba1);
ide_write(indexDevice,ATA_REG_LBA2, lba2);
ide_write(indexDevice,ATA_REG_HDDEVSEL, devSelected);
ide_write(indexDevice,ATA_REG_COMMAND, ATA_CMD_READ_PIO);
// ahora esperamos la disponibilidad de datos
err = 0;
while(!err) {
status = ide_read(indexDevice, ATA_REG_STATUS);
if (status & ATA_SR_ERR)
err = 1;
if (!err && !(status & ATA_SR_BSY) && (status & ATA_SR_DRDY))
// Everything is right.
err = 2;
}
if (err == 1)
{
// ocurrio un error, debo analizarlo
return 0;
}
// todo bien leamos los datos
ide_read_data(indexDevice,buffer);
return 1;
}
uint32_t loader() {
Elf32_Ehdr *elf;
Elf32_Phdr *ph = NULL;
uint8_t buf[4096];
#ifdef HAS_DEVICE
ide_read(buf, ELF_OFFSET_IN_DISK, 4096);
#else
ramdisk_read(buf, ELF_OFFSET_IN_DISK, 4096);
#endif
elf = (void*)buf;
/* TODO: fix the magic number with the correct one */
const uint32_t elf_magic = 0x7f454c46;
uint32_t *p_magic = (void *)buf;
nemu_assert(*p_magic == elf_magic);
/* Load each program segment */
for(; true; ) {
/* Scan the program header table, load each segment into memory */
if(ph->p_type == PT_LOAD) { //PT_LOAT=1, Loadable program segment
/* TODO: read the content of the segment from the ELF file
* to the memory region [VirtAddr, VirtAddr + FileSiz)
*/
/* TODO: zero the memory region
* [VirtAddr + FileSiz, VirtAddr + MemSiz)
*/
#ifdef IA32_PAGE
/* Record the program break for future use. */
extern uint32_t brk;
uint32_t new_brk = ph->p_vaddr + ph->p_memsz - 1;
if(brk < new_brk) { brk = new_brk; }
#endif
}
}
volatile uint32_t entry = elf->e_entry;
#ifdef IA32_PAGE
mm_malloc(KOFFSET - STACK_SIZE, STACK_SIZE);
#ifdef HAS_DEVICE
create_video_mapping();
#endif
write_cr3(get_ucr3());
#endif
return entry;
}
int fs_read(int fd, void *buf, int len) {
if (fd < 3) return 0;
assert(file_state[fd].opened);
if (file_state[fd].offset+len >= file_table[fd-3].size)
len = file_table[fd-3].size-file_state[fd].offset-1;
ide_read(buf, file_table[fd-3].disk_offset+file_state[fd].offset, len);
file_state[fd].offset += len;
return len;
}
int fs_read(int fd, void *buf, int len) {
//assert(state_array[i].opened == true);
if(!state_array[fd].opened) return -1;
int t = file_table[fd-3].size - state_array[fd].offset;
len = len>t? t : len;
ide_read(buf, file_table[fd-3].disk_offset + state_array[fd].offset, len);
state_array[fd].offset += len;
return len;
}
//Borrowed from os dev really tired will write my own in future.
unsigned char ide_polling(unsigned char channel, unsigned int advanced_check) {
for(int i = 0; i < 4; i++)
ide_read(channel, ATA_REG_ALTSTATUS);
while (ide_read(channel, ATA_REG_STATUS) & ATA_SR_BSY)
;
if (advanced_check) {
unsigned char state = ide_read(channel, ATA_REG_STATUS);
if (state & ATA_SR_ERROR)
panic();
if (state & ATA_SR_DF)
return 1;
if ((state & ATA_SR_DRQ) == 0)
return 3;
}
return 0;
}
/* 回收inode的数据块和inode本身 */
void inode_release(struct partition* part, uint32_t inode_no) {
struct inode* inode_to_del = inode_open(part, inode_no);
ASSERT(inode_to_del->i_no == inode_no);
/* 1 回收inode占用的所有块 */
uint8_t block_idx = 0, block_cnt = 12;
uint32_t block_bitmap_idx;
uint32_t all_blocks[140] = {0}; //12个直接块+128个间接块
/* a 先将前12个直接块存入all_blocks */
while (block_idx < 12) {
all_blocks[block_idx] = inode_to_del->i_sectors[block_idx];
block_idx++;
}
/* b 如果一级间接块表存在,将其128个间接块读到all_blocks[12~], 并释放一级间接块表所占的扇区 */
if (inode_to_del->i_sectors[12] != 0) {
ide_read(part->my_disk, inode_to_del->i_sectors[12], all_blocks + 12, 1);
block_cnt = 140;
/* 回收一级间接块表占用的扇区 */
block_bitmap_idx = inode_to_del->i_sectors[12] - part->sb->data_start_lba;
ASSERT(block_bitmap_idx > 0);
bitmap_set(&part->block_bitmap, block_bitmap_idx, 0);
bitmap_sync(cur_part, block_bitmap_idx, BLOCK_BITMAP);
}
/* c inode所有的块地址已经收集到all_blocks中,下面逐个回收 */
block_idx = 0;
while (block_idx < block_cnt) {
if (all_blocks[block_idx] != 0) {
block_bitmap_idx = 0;
block_bitmap_idx = all_blocks[block_idx] - part->sb->data_start_lba;
ASSERT(block_bitmap_idx > 0);
bitmap_set(&part->block_bitmap, block_bitmap_idx, 0);
bitmap_sync(cur_part, block_bitmap_idx, BLOCK_BITMAP);
}
block_idx++;
}
/*2 回收该inode所占用的inode */
bitmap_set(&part->inode_bitmap, inode_no, 0);
bitmap_sync(cur_part, inode_no, INODE_BITMAP);
/****** 以下inode_delete是调试用的 ******
* 此函数会在inode_table中将此inode清0,
* 但实际上是不需要的,inode分配是由inode位图控制的,
* 硬盘上的数据不需要清0,可以直接覆盖*/
void* io_buf = sys_malloc(1024);
inode_delete(part, inode_no, io_buf);
sys_free(io_buf);
/***********************************************/
inode_close(inode_to_del);
}
int fs_read(int fd, void *buf, size_t len) {
if (fd < 3) return -1;
assert(fd < NR_FILES + 3);
assert(f_state[fd].opened);
int max_len = file_table[fd - 3].size - f_state[fd].offset;
assert(max_len >= 0);
if (max_len < len) len = max_len;
ide_read(buf, file_table[fd - 3].disk_offset + f_state[fd].offset, len);
f_state[fd].offset += len;
return len;
}
// Fault any disk block that is read or written in to memory by
// loading it from disk.
// Hint: Use ide_read and BLKSECTS.
static void
bc_pgfault(struct UTrapframe *utf)
{
void *addr = (void *) utf->utf_fault_va;
uint64_t blockno = ((uint64_t)addr - DISKMAP) / BLKSIZE;
int r;
// Check that the fault was within the block cache region
if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
panic("page fault in FS: eip %08x, va %08x, err %04x",
utf->utf_rip, addr, utf->utf_err);
// Sanity check the block number.
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
// Allocate a page in the disk map region, read the contents
// of the block from the disk into that page, and mark the
// page not-dirty (since reading the data from disk will mark
// the page dirty).
//
// LAB 5: Your code here
if((r= sys_page_alloc(0, ROUNDDOWN(addr,PGSIZE), PTE_SYSCALL)) < 0)
panic("File System page fault handler couldn't alloc new page at addr %d. %e",addr, r);
//if(super)
// cprintf("12 %d\n",super->s_nblocks);
#ifndef VMM_GUEST
if((r = ide_read(blockno*BLKSECTS, ROUNDDOWN(addr,BLKSIZE), BLKSECTS)) < 0)
#else
if((r = host_read(BLKSECTS*blockno, ROUNDDOWN(addr,BLKSIZE), BLKSECTS)) < 0)
#endif
panic("File System page fault handler couldn't read in the data from disk. %e", r);
//if(super)
// cprintf("13 %d\n",super->s_nblocks);
if((r = sys_page_map(0, ROUNDDOWN(addr,PGSIZE), 0, ROUNDDOWN(addr,BLKSIZE), PTE_P| PTE_U | PTE_W)) < 0) //PTE_SYSCALL&~PTE_D
panic("Couldn't map page not dirty bc_pageflt %e",r);
//if(super)
// cprintf("14 %d\n",super->s_nblocks);
//cprintf("Handled the Fault\n");
//panic("bc_pgfault not implemented");
// Check that the block we read was allocated. (exercise for
// the reader: why do we do this *after* reading the block
// in?)
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
}
/* 将硬盘分区part上的inode清空 */
void inode_delete(struct partition* part, uint32_t inode_no, void* io_buf) {
ASSERT(inode_no < 4096);
struct inode_position inode_pos;
inode_locate(part, inode_no, &inode_pos); // inode位置信息会存入inode_pos
ASSERT(inode_pos.sec_lba <= (part->start_lba + part->sec_cnt));
char* inode_buf = (char*)io_buf;
if (inode_pos.two_sec) { // inode跨扇区,读入2个扇区
/* 将原硬盘上的内容先读出来 */
ide_read(part->my_disk, inode_pos.sec_lba, inode_buf, 2);
/* 将inode_buf清0 */
memset((inode_buf + inode_pos.off_size), 0, sizeof(struct inode));
/* 用清0的内存数据覆盖磁盘 */
ide_write(part->my_disk, inode_pos.sec_lba, inode_buf, 2);
} else { // 未跨扇区,只读入1个扇区就好
/* 将原硬盘上的内容先读出来 */
ide_read(part->my_disk, inode_pos.sec_lba, inode_buf, 1);
/* 将inode_buf清0 */
memset((inode_buf + inode_pos.off_size), 0, sizeof(struct inode));
/* 用清0的内存数据覆盖磁盘 */
ide_write(part->my_disk, inode_pos.sec_lba, inode_buf, 1);
}
}
unsigned char ide_polling(unsigned char channel, unsigned int advanced_check) {
// (I) Delay 400 nanosecond for BSY to be set:
// -------------------------------------------------
int i;
for(i = 0; i < 4; i++)
ide_read(channel, ATA_REG_ALTSTATUS); // Reading the Alternate Status port wastes 100ns; loop four times.
// (II) Wait for BSY to be cleared:
// -------------------------------------------------
while (ide_read(channel, ATA_REG_STATUS) & ATA_SR_BSY)
; // Wait for BSY to be zero.
if (advanced_check) {
unsigned char state = ide_read(channel, ATA_REG_STATUS); // Read Status Register.
// (III) Check For Errors:
// -------------------------------------------------
if (state & ATA_SR_ERR)
return 2; // Error.
// (IV) Check If Device fault:
// -------------------------------------------------
if (state & ATA_SR_DF)
return 1; // Device Fault.
// (V) Check DRQ:
// -------------------------------------------------
// BSY = 0; DF = 0; ERR = 0 so we should check for DRQ now.
if ((state & ATA_SR_DRQ) == 0)
return 3; // DRQ should be set
}
return 0; // No Error.
}
/* Read n sectors from the hard disk using PIO mode */
int ide_read(uint32 linear, uint32 numsects, void * bufptr) {
int i;
uint32 cyl,head,sector;
if (numsects > 1) {
for (i=0; i<numsects; i++) {
if (ide_read(linear+i, 1, ((uint8 *)bufptr)+i*512) < 0)
return -1;
}
} else {
linear_to_chs(linear, &cyl, &head, §or);
if (ide_read_chs(cyl, head, sector, numsects, (uint8*)bufptr) < 0)
return -1;
}
return 0;
}
// Fault any disk block that is read in to memory by
// loading it from disk.
static void
bc_pgfault(struct UTrapframe *utf)
{
void *addr = (void *) utf->utf_fault_va;
uint32_t blockno = ((uint32_t)addr - DISKMAP) / BLKSIZE;
int r;
// Check that the fault was within the block cache region
if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
panic("page fault in FS: eip %08x, va %08x, err %04x",
utf->utf_eip, addr, utf->utf_err);
// Sanity check the block number.
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
// Allocate a page in the disk map region, read the contents
// of the block from the disk into that page.
// Hint: first round addr to page boundary. fs/ide.c has code to read
// the disk.
//
// LAB 5: you code here:
addr = (void *)ROUNDDOWN(addr, PGSIZE);
if ((r = sys_page_alloc(0, addr, PTE_P | PTE_U | PTE_W)) < 0) {
panic("bc_pgfault: sys_page_alloc error %e\n", r);
}
if ((r = ide_read(BLKSECTS * blockno, addr, BLKSECTS)) < 0) {
panic("bc_pgfault: ide_read error %e\n", r);
}
// Clear the dirty bit for the disk block page since we just read the
// block from disk
if ((r = sys_page_map(0, addr, 0, addr, uvpt[PGNUM(addr)] & PTE_SYSCALL)) < 0)
panic("in bc_pgfault, sys_page_map: %e", r);
// Check that the block we read was allocated. (exercise for
// the reader: why do we do this *after* reading the block
// in?)
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
}
// Fault any disk block that is read in to memory by
// loading it from disk.
// Hint: Use ide_read and BLKSECTS.
static void
bc_pgfault(struct UTrapframe *utf)
{
void *addr = (void *) utf->utf_fault_va;
uint64_t blockno = ((uint64_t)addr - DISKMAP) / BLKSIZE;
int r;
// Check that the fault was within the block cache region
if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
panic("page fault in FS: eip %08x, va %08x, err %04x",
utf->utf_rip, addr, utf->utf_err);
// Sanity check the block number.
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
// Allocate a page in the disk map region, read the contents
// of the block from the disk into that page.
// Hint: first round addr to page boundary.
//
// LAB 5: your code here:
addr = ROUNDDOWN(addr, PGSIZE);
if(0 != sys_page_alloc(0, (void*)addr, PTE_SYSCALL)){
panic("Page Allocation Failed during handling page fault in FS");
}
#ifdef VMM_GUEST
if(0 != host_read((uint32_t) (blockno * BLKSECTS), (void*)addr, BLKSECTS))
{
panic("ide read failed in Page Fault Handling");
}
#else
if(0 != ide_read((uint32_t) (blockno * BLKSECTS), (void*)addr, BLKSECTS))
{
panic("ide read failed in Page Fault Handling");
}
#endif
if ((r = sys_page_map(0, addr, 0, addr, uvpt[PGNUM(addr)] & PTE_SYSCALL)) < 0)
panic("in bc_pgfault, sys_page_map: %e", r);
// Check that the block we read was allocated. (exercise for
// the reader: why do we do this *after* reading the block
// in?)
if (bitmap && block_is_free(blockno))
panic("reading free block %08x\n", blockno);
}
// Fault any disk block that is read in to memory by
// loading it from disk.
static void
bc_pgfault(struct UTrapframe *utf)
{
void *addr = (void *) utf->utf_fault_va;
uint64_t blockno = ((uint64_t)addr - DISKMAP) / BLKSIZE;
int r;
// Check that the fault was within the block cache region
if (addr < (void*)DISKMAP || addr >= (void*)(DISKMAP + DISKSIZE))
panic("page fault in FS: eip %08x, va %08x, err %04x",
utf->utf_rip, addr, utf->utf_err);
// Sanity check the block number.
if (super && blockno >= super->s_nblocks)
panic("reading non-existent block %08x\n", blockno);
// Allocate a page in the disk map region, read the contents
// of the block from the disk into that page.
// Hint: first round addr to page boundary.
//
// LAB 5: your code here:
// Check that the block we read was allocated. (exercise for
// the reader: why do we do this *after* reading the block
// in?)
if (bitmap && block_is_free(blockno)) //doubtful
panic("reading free block %08x\n", blockno);
void *new_addr = ROUNDDOWN(addr, PGSIZE);
r = sys_page_alloc(0, new_addr, PTE_P|PTE_W|PTE_U);
if(r<0)
panic("Something wrong with allocation %e",r);
uint64_t sec_no = BLKSECTS * blockno;
size_t nsecs = BLKSECTS;
#ifdef VMM_GUEST
r = host_read(sec_no, new_addr, nsecs);
#else
r = ide_read(sec_no, new_addr, nsecs);
#endif
if(r<0)
panic("Something wrong with reading from the disk %e",r);
}
void kmain(ol_mmap_register_t mmr)
{
textinit();
clearscreen();
println("The openLoader kernel is executing. \n");
print("Current stack pointer: ");
ol_registers_t regs = getregs();
printnum(regs->esp, 16, FALSE, FALSE);
putc(0xa);
char status = inb(0x60);
if((status & 2) == 2)
{
println("The A20 gate is open.");
putc(0xa);
}
pic_init();
setIDT();
outb(OL_KBC_COMMAND, OL_KB_INIT); // enable the keyboard
// display mmap
init_mmap(mmr);
println("Multiboot memory map:\n");
display_mmap(mmr);
#if 0
uint8_t active = ide_init(bootdrive);
ide_read(0x100, 1<<20, &bootdrive[active], 60);
uint8_t eax = ata_identify();
printnum(active, 16, FALSE, FALSE);
#endif
putc(0xa);
println("Waiting for service interrupts..");
while(1) halt();
println("End of program reached!");
endprogram();
}
static LONG ide_identify(WORD dev)
{
LONG ret;
UWORD ifnum, ifdev;
ifnum = dev / 2; /* i.e. primary IDE, secondary IDE, ... */
ifdev = dev & 1; /* 0 or 1 */
KDEBUG(("ide_identify(%d [ifnum=%d ifdev=%d])\n", dev, ifnum, ifdev));
if (ide_device_exists(dev)) {
ret = ide_read(IDE_CMD_IDENTIFY_DEVICE,ifnum,ifdev,0L,1,
(UBYTE *)&identify,IDE_DATA_REGISTER_IS_BYTESWAPPED);
} else ret = EUNDEV;
if (ret < 0)
KDEBUG(("ide_identify(%d [ifnum=%d ifdev=%d]) ret=%ld\n", dev, ifnum, ifdev, ret));
return ret;
}