[PATCH 09/10] Add support for VMUFAT filesystem

[Adrian McMenamin <adrianmcmenamin@gmail.com>]

vmufat.h provides constants and common data structures to inode.c and super.c as well as a wrapper around calls to sb_read

Signed-off-by: Adrian McMenamin <adrianmcmenamin@gmail.com>

fs/vmufat/vmufat.h                   |  126 ++++

---


--- /dev/null
+++ b/fs/vmufat/vmufat.h
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Header file for VMUFAT filesystem */
+#ifndef _VMUFAT_H_
+#define _VMUFAT_H_
+
+/* maximum length of file name */
+#define VMUFAT_NAMELEN			12
+
+/* Some GNU utils might not list files with inode num 0 */
+#define VMUFAT_ZEROBLOCK		0x10000
+#define VMU_BLK_SZ			0x200
+#define	VMU_BLK_SZ16			0x100
+#define VMU_PHYS_SZ			0x100
+
+/* file allocation table markers */
+#define VMUFAT_FILE_END			0xFFFA
+#define VMUFAT_UNALLOCATED		0xFFFC
+#define VMUFAT_ERROR			0xFFFF
+
+/* parameters for possible VMU volume sizes */
+#define VMUFAT_MIN_BLK			0x04
+#define VMUFAT_MAX_BLK			0x10000
+
+/* specifcations for directory entries */
+#define VMU_DIR_RECORD_LEN		0x20
+#define VMU_DIR_RECORD_LEN16		0x10
+#define VMU_DIR_ENTRIES_PER_BLOCK	0x10
+#define VMUFAT_NAME_OFFSET		0x04
+#define VMUFAT_FIRSTBLOCK_OFFSET16	0x01
+#define VMUFAT_START_OFFSET16		0x01
+#define VMUFAT_SIZE_OFFSET16		0x0C
+#define VMUFAT_HEADER_OFFSET16		0x0D
+
+/* File types used in directory */
+#define VMU_GAME			0xCC
+#define VMU_DATA			0x33
+
+/* filesystem locations marked in the root block */
+#define VMU_LOCATION_FAT		0x23
+#define VMU_LOCATION_FATLEN		0x24
+#define VMU_LOCATION_DIR		0x25
+#define VMU_LOCATION_DIRLEN		0x26
+#define VMU_LOCATION_USRLEN		0x28 /* set to 200 by real hardware */
+
+/* date offsets */
+#define VMUFAT_SB_DATEOFFSET	0x30
+#define VMUFAT_FILE_DATEOFFSET	0x10
+
+#define EXEC				0111
+#define NOCOPY				0xFF
+#define CANCOPY				0x00
+
+u16 vmufat_get_fat(struct super_block *sb, long block);
+void vmufat_save_bcd(struct inode *in, char *bh, int index_to_dir);
+struct inode *vmufat_get_inode(struct super_block *sb, long ino);
+int vmufat_list_blocks(struct inode *in);
+
+enum vmufat_date {
+	VMUFAT_DIR_CENT	=		0x10,
+	VMUFAT_DIR_YEAR,
+	VMUFAT_DIR_MONTH,
+	VMUFAT_DIR_DAY,
+	VMUFAT_DIR_HOUR,
+	VMUFAT_DIR_MIN,
+	VMUFAT_DIR_SEC,
+	VMUFAT_DIR_DOW
+};
+
+/* constants for BCD conversion */
+#define SECONDS_PER_DAY			86400
+#define DAYS_PER_YEAR			365
+#define SECONDS_PER_HOUR		3600
+#define HOURS_PER_DAY			24
+#define SIXTY_MINS_OR_SECS		60
+#define FEB28				59
+#define DAYS_PER_WEEK			7
+#define START_OF_EPOCH			70
+#define CENTURY21			30
+#define CENTURY22			130
+
+struct memcard {
+	unsigned int sb_bnum;
+	unsigned int fat_bnum;
+	unsigned int fat_len;
+	unsigned int dir_bnum;
+	unsigned int dir_len;
+	unsigned int numblocks;
+	struct mutex mutex;
+};
+
+struct vmufat_block {
+	struct list_head b_list;
+	int bno;
+};
+
+struct vmufat_inode {
+	struct list_head blocks;
+	unsigned int nblcks;
+	enum vmufat_file_type {
+		GAME = 1,
+		DATA = 2
+	} ft;
+	struct inode vfs_inode;
+};
+
+static inline struct vmufat_inode *VMUFAT_I(struct inode *in)
+{
+	return container_of(in, struct vmufat_inode, vfs_inode);
+}
+
+struct vmufat_file_info {
+	u8 ftype;
+	int fblk;
+	char fname[VMUFAT_NAMELEN];
+};
+
+static struct buffer_head *vmufat_sb_bread(struct super_block *sb,
+	sector_t block)
+{
+	if (!sb)
+		return NULL;
+	return sb_bread(sb, block);
+}
+
+int vmufat_count_files(struct super_block *sb);
+#endif