7894fcd217
for f in *.{h,c}; do sed -i .sed 's/[[:blank:]]*$//' $f; done
(Thanks to Nicolás Wolovick)
57 lines
1.6 KiB
C
57 lines
1.6 KiB
C
// On-disk file system format.
|
|
// Both the kernel and user programs use this header file.
|
|
|
|
|
|
#define ROOTINO 1 // root i-number
|
|
#define BSIZE 512 // block size
|
|
|
|
// Disk layout:
|
|
// [ boot block | super block | log | inode blocks | free bit map | data blocks ]
|
|
//
|
|
// mkfs computes the super block and builds an initial file system. The super describes
|
|
// the disk layout:
|
|
struct superblock {
|
|
uint size; // Size of file system image (blocks)
|
|
uint nblocks; // Number of data blocks
|
|
uint ninodes; // Number of inodes.
|
|
uint nlog; // Number of log blocks
|
|
uint logstart; // Block number of first log block
|
|
uint inodestart; // Block number of first inode block
|
|
uint bmapstart; // Block number of first free map block
|
|
};
|
|
|
|
#define NDIRECT 12
|
|
#define NINDIRECT (BSIZE / sizeof(uint))
|
|
#define MAXFILE (NDIRECT + NINDIRECT)
|
|
|
|
// On-disk inode structure
|
|
struct dinode {
|
|
short type; // File type
|
|
short major; // Major device number (T_DEV only)
|
|
short minor; // Minor device number (T_DEV only)
|
|
short nlink; // Number of links to inode in file system
|
|
uint size; // Size of file (bytes)
|
|
uint addrs[NDIRECT+1]; // Data block addresses
|
|
};
|
|
|
|
// Inodes per block.
|
|
#define IPB (BSIZE / sizeof(struct dinode))
|
|
|
|
// Block containing inode i
|
|
#define IBLOCK(i, sb) ((i) / IPB + sb.inodestart)
|
|
|
|
// Bitmap bits per block
|
|
#define BPB (BSIZE*8)
|
|
|
|
// Block of free map containing bit for block b
|
|
#define BBLOCK(b, sb) (b/BPB + sb.bmapstart)
|
|
|
|
// Directory is a file containing a sequence of dirent structures.
|
|
#define DIRSIZ 14
|
|
|
|
struct dirent {
|
|
ushort inum;
|
|
char name[DIRSIZ];
|
|
};
|
|
|