ext2 as multiboot2 module

1 files changed, 144 insertions, 0 deletions

diff --git a/kernel/include/ext2.h b/kernel/include/ext2.h
new file mode 100644
index 0000000..1760fef
--- /dev/null
+++ b/kernel/include/ext2.h
@@ -0,0 +1,144 @@
+#ifndef EXT2_H
+#define EXT2_H
+
+#include <types.h>
+
+#include <libk/list.h>
+
+struct ext2_superblock_t {
+// base fields
+	uint32_t inodes_count;
+	uint32_t blocks_count;
+	uint32_t superuser_blocks;
+	uint32_t free_blocks;
+	uint32_t free_inodes;
+	uint32_t superblock_block;
+	uint32_t block_size;
+	uint32_t fragment_size;
+	uint32_t blocks_per_group;
+	uint32_t fragments_per_group;
+	uint32_t inodes_per_group;
+	uint32_t last_mount_time;
+	uint32_t last_write_time;
+	uint16_t mounts_since_fcsk;
+	uint16_t mounts_before_fcsk;
+	uint16_t signature;
+	uint16_t state;
+	uint16_t on_error;
+	uint16_t version_minor;
+	uint32_t last_time_fcsk;
+	uint32_t interval_fcsk;
+	uint32_t os_id;
+	uint32_t version_major;
+	uint16_t superuser_id;
+	uint16_t supergroup_id;
+// extended fields
+	uint32_t first_inode;
+	uint16_t inode_size;
+	uint16_t superblock_group;
+	uint32_t optional_features;
+	uint32_t required_features;
+	uint32_t ro_features;
+	uint8_t id[16];
+	uint8_t volume_name[16];
+	uint8_t path_name[64];
+	uint32_t compression;
+	uint8_t blocks_for_files;
+	uint8_t blocks_for_dirs;
+	uint16_t unused;
+	uint8_t journal_id[16];
+	uint32_t journal_inode;
+	uint32_t journal_device;
+	uint32_t orphan_inode_head;
+	// unused
+};
+typedef struct ext2_superblock_t ext2_superblock_t;
+
+struct ext2_bg_desc_t {
+	uint32_t block_bitmap;
+	uint32_t inode_bitmap;
+	uint32_t inode_block_address;
+	uint16_t free_blocks;
+	uint16_t free_inodes;
+	uint16_t dir_count;
+};
+typedef struct ext2_bg_desc_t ext2_bg_desc_t;
+
+struct ext2_inode_t {
+	uint16_t type_perms;
+	uint16_t user_id;
+	uint32_t size_lower;
+	uint32_t last_accessed;
+	uint32_t creation_time;
+	uint32_t last_modified;
+	uint32_t deletion_time;
+	uint16_t group_id;
+	uint16_t hard_links_count;
+	uint32_t sectors_used;
+	uint32_t flags;
+	uint8_t os_specific1[4];
+	uint32_t dbp[12];
+	uint32_t sibp;
+	uint32_t dibp;
+	uint32_t tibp;
+	uint32_t gen_number;
+	uint32_t eab;
+	uint32_t size_upper;
+	uint32_t fragment_address;
+	uint8_t os_specific2[12];
+};
+typedef struct ext2_inode_t ext2_inode_t;
+
+// inode type
+#define TYPE_FIFO		0x1000
+#define TYPE_CHAR_DEV		0x2000
+#define TYPE_DIR		0x4000
+#define TYPE_BLOCK DEV		0x6000
+#define TYPE_FILE		0x8000
+#define TYPE_SYMLINK		0xA000
+#define TYPE_SOCKET		0xC000
+
+// inode permission
+#define PERM_OE 0x001
+#define PERM_OR 0x002
+#define PERM_OW 0x004
+#define PERM_GE 0x008
+#define PERM_GR 0x010
+#define PERM_GW 0x020
+#define PERM_UE 0x040
+#define PERM_UR 0x080
+#define PERM_UW 0x100
+#define PERM_STICKY 0x200
+#define PERM_GID 0x400
+#define PERM_UID 0x800
+
+struct ext2_dentry_t {
+	uint32_t inode;
+	uint16_t size;
+	uint8_t name_length_lower;
+	uint8_t type;
+	char* name;
+};
+typedef struct ext2_dentry_t ext2_dentry_t;
+
+extern ext2_superblock_t* ext2_superblock;
+
+// size of structs
+#define BG_DESC_SIZE 32
+#define BLOCK_SIZE (uint32_t)(1024 << ext2_superblock->block_size)
+#define INODE_SIZE (ext2_superblock->inode_size)
+#define INODES_PER_BLOCK (BLOCK_SIZE / INODE_SIZE)
+
+
+void read_block(uint32_t block_num, void* block_ptr);
+void read_superblock(ext2_superblock_t* ext2_superblock);
+void read_bg_desc(uint32_t bg_desc, ext2_bg_desc_t* ext2_bg_desc);
+void read_inode(uint32_t starting_block_num, uint32_t inode_index, ext2_inode_t* ext2_inode);
+list_t* directory_to_entries(uint32_t inode);
+char* files_to_buffer(uint32_t inode);
+list_t* path_to_list(const char* path);
+uint32_t path_to_inode(const char* path);
+void ls(uint32_t inode);
+void print(uint32_t inode);
+
+#endif