path: root/fs/ntfs3/ntfs_fs.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 *
 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
 *
 */

// clang-format off
#ifndef _LINUX_NTFS3_NTFS_FS_H
#define _LINUX_NTFS3_NTFS_FS_H

#include <linux/blkdev.h>
#include <linux/buffer_head.h>
#include <linux/fs.h>
#include <linux/highmem.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/page-flags.h>
#include <linux/pagemap.h>
#include <linux/rbtree.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/time64.h>
#include <linux/types.h>
#include <linux/uidgid.h>
#include <asm/div64.h>
#include <asm/page.h>

#include "debug.h"
#include "ntfs.h"

struct dentry;
struct fiemap_extent_info;
struct user_namespace;
struct page;
struct writeback_control;
enum utf16_endian;


#define MINUS_ONE_T			((size_t)(-1))
/* Biggest MFT / smallest cluster */
#define MAXIMUM_BYTES_PER_MFT		4096
#define NTFS_BLOCKS_PER_MFT_RECORD	(MAXIMUM_BYTES_PER_MFT / 512)

#define MAXIMUM_BYTES_PER_INDEX		4096
#define NTFS_BLOCKS_PER_INODE		(MAXIMUM_BYTES_PER_INDEX / 512)

/* NTFS specific error code when fixup failed. */
#define E_NTFS_FIXUP			555
/* NTFS specific error code about resident->nonresident. */
#define E_NTFS_NONRESIDENT		556
/* NTFS specific error code about punch hole. */
#define E_NTFS_NOTALIGNED		557
/* NTFS specific error code when on-disk struct is corrupted. */
#define E_NTFS_CORRUPT			558


/* sbi->flags */
#define NTFS_FLAGS_NODISCARD		0x00000001
/* Set when LogFile is replaying. */
#define NTFS_FLAGS_LOG_REPLAYING	0x00000008
/* Set when we changed first MFT's which copy must be updated in $MftMirr. */
#define NTFS_FLAGS_MFTMIRR		0x00001000
#define NTFS_FLAGS_NEED_REPLAY		0x04000000


/* ni->ni_flags */
/*
 * Data attribute is external compressed (LZX/Xpress)
 * 1 - WOF_COMPRESSION_XPRESS4K
 * 2 - WOF_COMPRESSION_XPRESS8K
 * 3 - WOF_COMPRESSION_XPRESS16K
 * 4 - WOF_COMPRESSION_LZX32K
 */
#define NI_FLAG_COMPRESSED_MASK		0x0000000f
/* Data attribute is deduplicated. */
#define NI_FLAG_DEDUPLICATED		0x00000010
#define NI_FLAG_EA			0x00000020
#define NI_FLAG_DIR			0x00000040
#define NI_FLAG_RESIDENT		0x00000080
#define NI_FLAG_UPDATE_PARENT		0x00000100
// clang-format on

struct ntfs_mount_options {
	char *nls_name;
	struct nls_table *nls;

	kuid_t fs_uid;
	kgid_t fs_gid;
	u16 fs_fmask_inv;
	u16 fs_dmask_inv;

	unsigned fmask : 1; /* fmask was set. */
	unsigned dmask : 1; /*dmask was set. */
	unsigned sys_immutable : 1; /* Immutable system files. */
	unsigned discard : 1; /* Issue discard requests on deletions. */
	unsigned sparse : 1; /* Create sparse files. */
	unsigned showmeta : 1; /* Show meta files. */
	unsigned nohidden : 1; /* Do not show hidden files. */
	unsigned force : 1; /* RW mount dirty volume. */
	unsigned noacsrules : 1; /* Exclude acs rules. */
	unsigned prealloc : 1; /* Preallocate space when file is growing. */
};

/* Special value to unpack and deallocate. */
#define RUN_DEALLOCATE ((struct runs_tree *)(size_t)1)

/* TODO: Use rb tree instead of array. */
struct runs_tree {
	struct ntfs_run *runs;
	size_t count; /* Currently used size a ntfs_run storage. */
	size_t allocated; /* Currently allocated ntfs_run storage size. */
};

struct ntfs_buffers {
	/* Biggest MFT / smallest cluster = 4096 / 512 = 8 */
	/* Biggest index / smallest cluster = 4096 / 512 = 8 */
	struct buffer_head *bh[PAGE_SIZE >> SECTOR_SHIFT];
	u32 bytes;
	u32 nbufs;
	u32 off;
};

enum ALLOCATE_OPT {
	ALLOCATE_DEF = 0, // Allocate all clusters.
	ALLOCATE_MFT = 1, // Allocate for MFT.
};

enum bitmap_mutex_classes {
	BITMAP_MUTEX_CLUSTERS = 0,
	BITMAP_MUTEX_MFT = 1,
};

struct wnd_bitmap {
	struct super_block *sb;
	struct rw_semaphore rw_lock;

	struct runs_tree run;
	size_t nbits;

	size_t total_zeroes; // Total number of free bits.
	u16 *free_bits; // Free bits in each window.
	size_t nwnd;
	u32 bits_last; // Bits in last window.

	struct rb_root start_tree; // Extents, sorted by 'start'.
	struct rb_root count_tree; // Extents, sorted by 'count + start'.
	size_t count; // Extents count.

	/*
	 * -1 Tree is activated but not updated (too many fragments).
	 * 0 - Tree is not activated.
	 * 1 - Tree is activated and updated.
	 */
	int uptodated;
	size_t extent_min; // Minimal extent used while building.
	size_t extent_max; // Upper estimate of biggest free block.

	/* Zone [bit, end) */
	size_t zone_bit;
	size_t zone_end;

	bool set_tail; // Not necessary in driver.
	bool inited;
};

typedef int (*NTFS_CMP_FUNC)(const void *key1, size_t len1, const void *key2,
			     size_t len2, const void *param);

enum index_mutex_classed {
	INDEX_MUTEX_I30 = 0,
	INDEX_MUTEX_SII = 1,
	INDEX_MUTEX_SDH = 2,
	INDEX_MUTEX_SO = 3,
	INDEX_MUTEX_SQ = 4,
	INDEX_MUTEX_SR = 5,
	INDEX_MUTEX_TOTAL
};

/* ntfs_index - Allocation unit inside directory. */
struct ntfs_index {
	struct runs_tree bitmap_run;
	struct runs_tree alloc_run;
	/* read/write access to 'bitmap_run'/'alloc_run' while ntfs_readdir */
	struct rw_semaphore run_lock;

	/*TODO: Remove 'cmp'. */
	NTFS_CMP_FUNC cmp;

	u8 index_bits; // log2(root->index_block_size)
	u8 idx2vbn_bits; // log2(root->index_block_clst)
	u8 vbn2vbo_bits; // index_block_size < cluster? 9 : cluster_bits
	u8 type; // index_mutex_classed
};

/* Minimum MFT zone. */
#define NTFS_MIN_MFT_ZONE 100

/* Ntfs file system in-core superblock data. */
struct ntfs_sb_info {
	struct super_block *sb;

	u32 discard_granularity;
	u64 discard_granularity_mask_inv; // ~(discard_granularity_mask_inv-1)

	u32 cluster_size; // bytes per cluster
	u32 cluster_mask; // == cluster_size - 1
	u64 cluster_mask_inv; // ~(cluster_size - 1)
	u32 block_mask; // sb->s_blocksize - 1
	u32 blocks_per_cluster; // cluster_size / sb->s_blocksize

	u32 record_size;
	u32 index_size;

	u8 cluster_bits;
	u8 record_bits;

	u64 maxbytes; // Maximum size for normal files.
	u64 maxbytes_sparse; // Maximum size for