super.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 *  linux/fs/apfs/super.h
 *
 * Copyright (C) 2018 Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
 */

#ifndef _APFS_SUPER_H
#define _APFS_SUPER_H

#include <linux/fs.h>
#include <linux/types.h>
#include "object.h"

/*
 * Structure used to store a range of physical blocks
 */
struct apfs_prange {
	__le64 pr_start_paddr;
	__le64 pr_block_count;
} __packed;

/* Main container */

/* Container constants */
#define APFS_SUPER_MAGIC			0x4253584E

#define APFS_NX_MAGIC				APFS_SUPER_MAGIC
#define APFS_NX_BLOCK_NUM			0
#define APFS_NX_MAX_FILE_SYSTEMS		100

#define APFS_NX_EPH_INFO_COUNT			4
#define APFS_NX_EPH_MIN_BLOCK_COUNT		8
#define APFS_NX_MAX_FILE_SYSTEM_EPH_STRUCTS	4
#define APFS_NX_TX_MIN_CHECKPOINT_COUNT		4
#define APFS_NX_EPH_INFO_VERSION_1		1

/* Container flags */
#define APFS_NX_RESERVED_1			0x00000001LL
#define APFS_NX_RESERVED_2			0x00000002LL
#define APFS_NX_CRYPTO_SW			0x00000004LL

/* Optional container feature flags */
#define APFS_NX_FEATURE_DEFRAG			0x0000000000000001ULL
#define APFS_NX_FEATURE_LCFD			0x0000000000000002ULL
#define APFS_NX_SUPPORTED_FEATURES_MASK		(APFS_NX_FEATURE_DEFRAG | \
						APFS_NX_FEATURE_LCFD)

/* Read-only compatible container feature flags */
#define APFS_NX_SUPPORTED_ROCOMPAT_MASK		(0x0ULL)

/* Incompatible container feature flags */
#define APFS_NX_INCOMPAT_VERSION1		0x0000000000000001ULL
#define APFS_NX_INCOMPAT_VERSION2		0x0000000000000002ULL
#define APFS_NX_INCOMPAT_FUSION			0x0000000000000100ULL
#define APFS_NX_SUPPORTED_INCOMPAT_MASK		(APFS_NX_INCOMPAT_VERSION2 \
						| APFS_NX_INCOMPAT_FUSION)

/* Block and container sizes */
#define APFS_NX_MINIMUM_BLOCK_SIZE		4096
#define APFS_NX_DEFAULT_BLOCK_SIZE		4096
#define APFS_NX_MAXIMUM_BLOCK_SIZE		65536
#define APFS_NX_MINIMUM_CONTAINER_SIZE		1048576

/* Indexes into a container superblock's array of counters */
enum {
	APFS_NX_CNTR_OBJ_CKSUM_SET	= 0,
	APFS_NX_CNTR_OBJ_CKSUM_FAIL	= 1,

	APFS_NX_NUM_COUNTERS		= 32
};

/*
 * On-disk representation of the container superblock
 */
struct apfs_nx_superblock {
/*00*/	struct apfs_obj_phys nx_o;
/*20*/	__le32 nx_magic;
	__le32 nx_block_size;
	__le64 nx_block_count;

/*30*/	__le64 nx_features;
	__le64 nx_readonly_compatible_features;
	__le64 nx_incompatible_features;

/*48*/	char nx_uuid[16];

/*58*/	__le64 nx_next_oid;
	__le64 nx_next_xid;

/*68*/	__le32 nx_xp_desc_blocks;
	__le32 nx_xp_data_blocks;
/*70*/	__le64 nx_xp_desc_base;
	__le64 nx_xp_data_base;
	__le32 nx_xp_desc_next;
	__le32 nx_xp_data_next;
/*88*/	__le32 nx_xp_desc_index;
	__le32 nx_xp_desc_len;
	__le32 nx_xp_data_index;
	__le32 nx_xp_data_len;

/*98*/	__le64 nx_spaceman_oid;
	__le64 nx_omap_oid;
	__le64 nx_reaper_oid;

/*B0*/	__le32 nx_test_type;

	__le32 nx_max_file_systems;
/*B8*/	__le64 nx_fs_oid[APFS_NX_MAX_FILE_SYSTEMS];
/*3D8*/	__le64 nx_counters[APFS_NX_NUM_COUNTERS];
/*4D8*/	struct apfs_prange nx_blocked_out_prange;
	__le64 nx_evict_mapping_tree_oid;
/*4F0*/	__le64 nx_flags;
	__le64 nx_efi_jumpstart;
/*500*/	char nx_fusion_uuid[16];
	struct apfs_prange nx_keylocker;
/*520*/	__le64 nx_ephemeral_info[APFS_NX_EPH_INFO_COUNT];

/*540*/	__le64 nx_test_oid;

	__le64 nx_fusion_mt_oid;
/*550*/	__le64 nx_fusion_wbc_oid;
	struct apfs_prange nx_fusion_wbc;
} __packed;

/* Volume */

/* Volume constants */
#define APFS_MAGIC				0x42535041

#define APFS_MAX_HIST				8
#define APFS_VOLNAME_LEN			256

/* Volume flags */
#define APFS_FS_UNENCRYPTED			0x00000001LL
#define APFS_FS_EFFACEABLE			0x00000002LL
#define APFS_FS_RESERVED_4			0x00000004LL
#define APFS_FS_ONEKEY				0x00000008LL
#define APFS_FS_SPILLEDOVER			0x00000010LL
#define APFS_FS_RUN_SPILLOVER_CLEANER		0x00000020LL
#define APFS_FS_FLAGS_VALID_MASK		(APFS_FS_UNENCRYPTED \
						| APFS_FS_EFFACEABLE \
						| APFS_FS_RESERVED_4 \
						| APFS_FS_ONEKEY \
						| APFS_FS_SPILLEDOVER \
						| APFS_FS_RUN_SPILLOVER_CLEANER)

#define APFS_FS_CRYPTOFLAGS			(APFS_FS_UNENCRYPTED \
						| APFS_FS_EFFACEABLE \
						| APFS_FS_ONEKEY)

/* Optional volume feature flags */
#define APFS_FEATURE_DEFRAG_PRERELEASE		0x00000001LL
#define APFS_FEATURE_HARDLINK_MAP_RECORDS	0x00000002LL
#define APFS_FEATURE_DEFRAG			0x00000004LL

#define APFS_SUPPORTED_FEATURES_MASK	(APFS_FEATURE_DEFRAG \
					| APFS_FEATURE_DEFRAG_PRERELEASE \
					| APFS_FEATURE_HARDLINK_MAP_RECORDS)

/* Read-only compatible volume feature flags */
#define APFS_SUPPORTED_ROCOMPAT_MASK		(0x0ULL)

/* Incompatible volume feature flags */
#define APFS_INCOMPAT_CASE_INSENSITIVE		0x00000001LL
#define APFS_INCOMPAT_DATALESS_SNAPS		0x00000002LL
#define APFS_INCOMPAT_ENC_ROLLED		0x00000004LL
#define APFS_INCOMPAT_NORMALIZATION_INSENSITIVE	0x00000008LL

#define APFS_SUPPORTED_INCOMPAT_MASK  (APFS_INCOMPAT_CASE_INSENSITIVE \
				      | APFS_INCOMPAT_DATALESS_SNAPS \
				      | APFS_INCOMPAT_ENC_ROLLED \
				      | APFS_INCOMPAT_NORMALIZATION_INSENSITIVE)

#define APFS_MODIFIED_NAMELEN	      32

/*
 * Structure containing information about a program that modified the volume
 */
struct apfs_modified_by {
	char id[APFS_MODIFIED_NAMELEN];
	__le64 timestamp;
	__le64 last_xid;
} __packed;

/*
 * Structure used to store the encryption state
 */
struct apfs_wrapped_meta_crypto_state {
	__le16 major_version;
	__le16 minor_version;
	__le32 cpflags;
	__le32 persistent_class;
	__le32 key_os_version;
	__le16 key_revision;
	__le16 unused;
} __packed;

/*
 * On-disk representation of a volume superblock
 */
struct apfs_superblock {
/*00*/	struct apfs_obj_phys apfs_o;

/*20*/	__le32 apfs_magic;
	__le32 apfs_fs_index;

/*28*/	__le64 apfs_features;
	__le64 apfs_readonly_compatible_features;
	__le64 apfs_incompatible_features;

/*40*/	__le64 apfs_unmount_time;

	__le64 apfs_fs_reserve_block_count;
	__le64 apfs_fs_quota_block_count;
	__le64 apfs_fs_alloc_count;

/*60*/	struct apfs_wrapped_meta_crypto_state apfs_meta_crypto;

/*74*/	__le32 apfs_root_tree_type;
	__le32 apfs_extentref_tree_type;
	__le32 apfs_snap_meta_tree_type;

/*80*/	__le64 apfs_omap_oid;
	__le64 apfs_root_tree_oid;
	__le64 apfs_extentref_tree_oid;
	__le64 apfs_snap_meta_tree_oid;

/*A0*/	__le64 apfs_revert_to_xid;
	__le64 apfs_revert_to_sblock_oid;

/*B0*/	__le64 apfs_next_obj_id;

/*B8*/	__le64 apfs_num_files;
	__le64 apfs_num_directories;
	__le64 apfs_num_symlinks;
	__le64 apfs_num_other_fsobjects;
	__le64 apfs_num_snapshots;

/*E0*/	__le64 apfs_total_blocks_alloced;
	__le64 apfs_total_blocks_freed;

/*F0*/	char apfs_vol_uuid[16];
/*100*/	__le64 apfs_last_mod_time;

	__le64 apfs_fs_flags;

/*110*/	struct apfs_modified_by apfs_formatted_by;
/*140*/	struct apfs_modified_by apfs_modified_by[APFS_MAX_HIST];

/*2C0*/	u8 apfs_volname[APFS_VOLNAME_LEN];
/*3C0*/	__le32 apfs_next_doc_id;

	__le16 apfs_role;
	__le16 reserved;

/*3C8*/	__le64 apfs_root_to_xid;
	__le64 apfs_er_state_oid;
} __packed;

/* Mount option flags */
#define APFS_UID_OVERRIDE	1
#define APFS_GID_OVERRIDE	2
#define APFS_CHECK_NODES	4

/*
 * Superblock data in memory, both from the main superblock and the volume
 * checkpoint superblock.
 */
struct apfs_sb_info {
	struct apfs_nx_superblock *s_msb_raw;		/* On-disk main sb */
	struct apfs_superblock *s_vsb_raw;		/* On-disk volume sb */

	u64 s_xid;			/* Latest transaction id */
	struct apfs_node *s_cat_root;	/* Root of the catalog tree */
	struct apfs_node *s_omap_root;	/* Root of the object map tree */

	struct apfs_object s_mobject;	/* Main superblock object */
	struct apfs_object s_vobject;	/* Volume superblock object */

	/* Mount options */
	unsigned int s_flags;
	unsigned int s_vol_nr;		/* Index of the volume in the sb list */
	kuid_t s_uid;			/* uid to override on-disk uid */
	kgid_t s_gid;			/* gid to override on-disk gid */

	/* TODO: handle block sizes above the maximum of PAGE_SIZE? */
	unsigned long s_blocksize;
	unsigned char s_blocksize_bits;
};

static inline struct apfs_sb_info *APFS_SB(struct super_block *sb)
{
	return sb->s_fs_info;
}

static inline bool apfs_is_case_insensitive(struct super_block *sb)
{
	return (APFS_SB(sb)->s_vsb_raw->apfs_incompatible_features &
	       cpu_to_le64(APFS_INCOMPAT_CASE_INSENSITIVE)) != 0;
}

#endif	/* _APFS_SUPER_H */