filesystem structure intro and docs

- new type pid_t and program management mechanism to make it
  easier to switch to a multitasking kernel
- new memory related functions in memory.h to move, copy and
  manage pages
- fix typos

1 files changed, 77 insertions, 0 deletions

diff --git a/sw/z80/kernel/include/filesystem.h b/sw/z80/kernel/include/filesystem.h
new file mode 100644
index 0000000..6505d5e
--- /dev/null
+++ b/sw/z80/kernel/include/filesystem.h
@@ -0,0 +1,77 @@
+#ifndef __FILESYSTEM_H__
+#define __FILESYSTEM_H__
+
+#include "types.h"
+
+#define FS_OFFSET 0x1000
+
+#define FS_BLOCK_SIZE   512
+#define FS_BLOCKS_N     12
+/* #define FS_IBLOCKS_N     1 */
+
+#define INODE_TYPE_FILE 0
+#define INODE_TYPE_DIR  1
+#define INODE_TYPE_LINK 2
+
+typedef struct time_s
+{
+    uint16_t time;
+    uint16_t date;
+} time_t;
+
+
+/* on-disk structures */
+struct fs_superblock
+{
+    uint8_t     magic;
+    uint16_t    blk_size;   /* default is 512 bytes */
+    uint16_t    imap_size;  /* size of the inode bitmap in blocks */
+    uint16_t    dmap_size;  /* size of the data blocks map in blocks */
+};
+
+
+struct fs_blk
+{
+    uint    size;
+};
+
+typedef struct fs_inode
+{
+    uint        i_used :1; // inode is free
+    uint        i_mode :3; // inode mode (rwx)
+
+    uint8_t     i_uid;     // user (owner) id
+    uint16_t    i_number;  // identifier
+
+    uint16_t    i_blocks;  // number of blocks
+
+    struct fs_blk   i_block[FS_BLOCKS_N];   // direct blocks
+/*    struct fs_blk   i_iblock[FS_IBLOCKS_N]; // indirect blocks */
+    
+    inode_t     *parent;
+} inode_t;
+
+/* inode table structures */
+struct fs_inode_entry
+{
+    uint16_t    i_number;
+    uint8_t     str_len;
+    char        name[24];
+};
+
+/* filesystem struct for the operating system */
+struct filesystem
+{
+    size_t size;
+    size_t fsize;
+    inode_t *mntpt;
+};
+
+void fs_parse_superblock(struct filesystem *fs);
+
+void fs_write_imap();
+void fs_write_dmap();
+
+/* void fs_ */
+
+#endif // __FILESYSTEM_H__