[thirdparty/linux.git] / fs / erofs / internal.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2017-2018 HUAWEI, Inc.
 *             http://www.huawei.com/
 * Created by Gao Xiang <gaoxiang25@huawei.com>
 */
#ifndef __EROFS_INTERNAL_H
#define __EROFS_INTERNAL_H

#include <linux/fs.h>
#include <linux/dcache.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/bio.h>
#include <linux/buffer_head.h>
#include <linux/magic.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include "erofs_fs.h"

/* redefine pr_fmt "erofs: " */
#undef pr_fmt
#define pr_fmt(fmt) "erofs: " fmt

__printf(3, 4) void _erofs_err(struct super_block *sb,
			       const char *function, const char *fmt, ...);
#define erofs_err(sb, fmt, ...)	\
	_erofs_err(sb, __func__, fmt "\n", ##__VA_ARGS__)
__printf(3, 4) void _erofs_info(struct super_block *sb,
			       const char *function, const char *fmt, ...);
#define erofs_info(sb, fmt, ...) \
	_erofs_info(sb, __func__, fmt "\n", ##__VA_ARGS__)
#ifdef CONFIG_EROFS_FS_DEBUG
#define erofs_dbg(x, ...)       pr_debug(x "\n", ##__VA_ARGS__)
#define DBG_BUGON               BUG_ON
#else
#define erofs_dbg(x, ...)       ((void)0)
#define DBG_BUGON(x)            ((void)(x))
#endif	/* !CONFIG_EROFS_FS_DEBUG */

/* EROFS_SUPER_MAGIC_V1 to represent the whole file system */
#define EROFS_SUPER_MAGIC   EROFS_SUPER_MAGIC_V1

typedef u64 erofs_nid_t;
typedef u64 erofs_off_t;
/* data type for filesystem-wide blocks number */
typedef u32 erofs_blk_t;

struct erofs_sb_info {
#ifdef CONFIG_EROFS_FS_ZIP
	/* list for all registered superblocks, mainly for shrinker */
	struct list_head list;
	struct mutex umount_mutex;

	/* managed XArray arranged in physical block number */
	struct xarray managed_pslots;

	/* threshold for decompression synchronously */
	unsigned int max_sync_decompress_pages;

	unsigned int shrinker_run_no;

	/* current strategy of how to use managed cache */
	unsigned char cache_strategy;

	/* pseudo inode to manage cached pages */
	struct inode *managed_cache;
#endif	/* CONFIG_EROFS_FS_ZIP */
	u32 blocks;
	u32 meta_blkaddr;
#ifdef CONFIG_EROFS_FS_XATTR
	u32 xattr_blkaddr;
#endif

	/* inode slot unit size in bit shift */
	unsigned char islotbits;

	u32 build_time_nsec;
	u64 build_time;

	/* what we really care is nid, rather than ino.. */
	erofs_nid_t root_nid;
	/* used for statfs, f_files - f_favail */
	u64 inos;

	u8 uuid[16];                    /* 128-bit uuid for volume */
	u8 volume_name[16];             /* volume name */
	u32 feature_compat;
	u32 feature_incompat;

	unsigned int mount_opt;
};

#define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
#define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)

/* Mount flags set via mount options or defaults */
#define EROFS_MOUNT_XATTR_USER		0x00000010
#define EROFS_MOUNT_POSIX_ACL		0x00000020

#define clear_opt(sbi, option)	((sbi)->mount_opt &= ~EROFS_MOUNT_##option)
#define set_opt(sbi, option)	((sbi)->mount_opt |= EROFS_MOUNT_##option)
#define test_opt(sbi, option)	((sbi)->mount_opt & EROFS_MOUNT_##option)

#ifdef CONFIG_EROFS_FS_ZIP
enum {
	EROFS_ZIP_CACHE_DISABLED,
	EROFS_ZIP_CACHE_READAHEAD,
	EROFS_ZIP_CACHE_READAROUND
};

#define EROFS_LOCKED_MAGIC     (INT_MIN | 0xE0F510CCL)

/* basic unit of the workstation of a super_block */
struct erofs_workgroup {
	/* the workgroup index in the workstation */
	pgoff_t index;

	/* overall workgroup reference count */
	atomic_t refcount;
};

#if defined(CONFIG_SMP)
static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
						 int val)
{
	preempt_disable();
	if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
		preempt_enable();
		return false;
	}
	return true;
}

static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
					    int orig_val)
{
	/*
	 * other observers should notice all modifications
	 * in the freezing period.
	 */
	smp_mb();
	atomic_set(&grp->refcount, orig_val);
	preempt_enable();
}

static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
{
	return atomic_cond_read_relaxed(&grp->refcount,
					VAL != EROFS_LOCKED_MAGIC);
}
#else
static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
						 int val)
{
	preempt_disable();
	/* no need to spin on UP platforms, let's just disable preemption. */
	if (val != atomic_read(&grp->refcount)) {
		preempt_enable();
		return false;
	}
	return true;
}

static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
					    int orig_val)
{
	preempt_enable();
}

static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
{
	int v = atomic_read(&grp->refcount);

	/* workgroup is never freezed on uniprocessor systems */
	DBG_BUGON(v == EROFS_LOCKED_MAGIC);
	return v;
}
#endif	/* !CONFIG_SMP */

/* hard limit of pages per compressed cluster */
#define Z_EROFS_CLUSTER_MAX_PAGES       (CONFIG_EROFS_FS_CLUSTER_PAGE_LIMIT)
#define EROFS_PCPUBUF_NR_PAGES          Z_EROFS_CLUSTER_MAX_PAGES
#else
#define EROFS_PCPUBUF_NR_PAGES          0
#endif	/* !CONFIG_EROFS_FS_ZIP */

/* we strictly follow PAGE_SIZE and no buffer head yet */
#define LOG_BLOCK_SIZE		PAGE_SHIFT

#undef LOG_SECTORS_PER_BLOCK
#define LOG_SECTORS_PER_BLOCK	(PAGE_SHIFT - 9)

#undef SECTORS_PER_BLOCK
#define SECTORS_PER_BLOCK	(1 << SECTORS_PER_BLOCK)

#define EROFS_BLKSIZ		(1 << LOG_BLOCK_SIZE)

#if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ)
#error erofs cannot be used in this platform
#endif

#define ROOT_NID(sb)		((sb)->root_nid)

#define erofs_blknr(addr)       ((addr) / EROFS_BLKSIZ)
#define erofs_blkoff(addr)      ((addr) % EROFS_BLKSIZ)
#define blknr_to_addr(nr)       ((erofs_off_t)(nr) * EROFS_BLKSIZ)

static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid)
{
	return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits);
}

/* atomic flag definitions */
#define EROFS_I_EA_INITED_BIT	0
#define EROFS_I_Z_INITED_BIT	1

/* bitlock definitions (arranged in reverse order) */
#define EROFS_I_BL_XATTR_BIT	(BITS_PER_LONG - 1)
#define EROFS_I_BL_Z_BIT	(BITS_PER_LONG - 2)

struct erofs_inode {
	erofs_nid_t nid;

	/* atomic flags (including bitlocks) */
	unsigned long flags;

	unsigned char datalayout;
	unsigned char inode_isize;
	unsigned short xattr_isize;

	unsigned int xattr_shared_count;
	unsigned int *xattr_shared_xattrs;

	union {
		erofs_blk_t raw_blkaddr;
#ifdef CONFIG_EROFS_FS_ZIP
		struct {
			unsigned short z_advise;
			unsigned char  z_algorithmtype[2];
			unsigned char  z_logical_clusterbits;
			unsigned char  z_physical_clusterbits[2];
		};
#endif	/* CONFIG_EROFS_FS_ZIP */
	};
	/* the corresponding vfs inode */
	struct inode vfs_inode;
};

#define EROFS_I(ptr)	\
	container_of(ptr, struct erofs_inode, vfs_inode)

static inline unsigned long erofs_inode_datablocks(struct inode *inode)
{
	/* since i_size cannot be changed */
	return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ);
}

static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
					  unsigned int bits)
{

	return (value >> bit) & ((1 << bits) - 1);
}


static inline unsigned int erofs_inode_version(unsigned int value)
{
	return erofs_bitrange(value, EROFS_I_VERSION_BIT,
			      EROFS_I_VERSION_BITS);
}

static inline unsigned int erofs_inode_datalayout(unsigned int value)
{
	return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
			      EROFS_I_DATALAYOUT_BITS);
}

extern const struct super_operations erofs_sops;

extern const struct address_space_operations erofs_raw_access_aops;
extern const struct address_space_operations z_erofs_aops;

/*
 * Logical to physical block mapping, used by erofs_map_blocks()
 *
 * Different with other file systems, it is used for 2 access modes:
 *
 * 1) RAW access mode:
 *
 * Users pass a valid (m_lblk, m_lofs -- usually 0) pair,
 * and get the valid m_pblk, m_pofs and the longest m_len(in bytes).
 *
 * Note that m_lblk in the RAW access mode refers to the number of
 * the compressed ondisk block rather than the uncompressed
 * in-memory block for the compressed file.
 *
 * m_pofs equals to m_lofs except for the inline data page.
 *
 * 2) Normal access mode:
 *
 * If the inode is not compressed, it has no difference with
 * the RAW access mode. However, if the inode is compressed,
 * users should pass a valid (m_lblk, m_lofs) pair, and get
 * the needed m_pblk, m_pofs, m_len to get the compressed data
 * and the updated m_lblk, m_lofs which indicates the start
 * of the corresponding uncompressed data in the file.
 */
enum {
	BH_Zipped = BH_PrivateStart,
	BH_FullMapped,
};

/* Has a disk mapping */
#define EROFS_MAP_MAPPED	(1 << BH_Mapped)
/* Located in metadata (could be copied from bd_inode) */
#define EROFS_MAP_META		(1 << BH_Meta)
/* The extent has been compressed */
#define EROFS_MAP_ZIPPED	(1 << BH_Zipped)
/* The length of extent is full */
#define EROFS_MAP_FULL_MAPPED	(1 << BH_FullMapped)

struct erofs_map_blocks {
	erofs_off_t m_pa, m_la;
	u64 m_plen, m_llen;

	unsigned int m_flags;

	struct page *mpage;
};

/* Flags used by erofs_map_blocks() */
#define EROFS_GET_BLOCKS_RAW    0x0001

/* zmap.c */
#ifdef CONFIG_EROFS_FS_ZIP
int z_erofs_fill_inode(struct inode *inode);
int z_erofs_map_blocks_iter(struct inode *inode,
			    struct erofs_map_blocks *map,
			    int flags);
#else
static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; }
static inline int z_erofs_map_blocks_iter(struct inode *inode,
					  struct erofs_map_blocks *map,
					  int flags)
{
	return -EOPNOTSUPP;
}
#endif	/* !CONFIG_EROFS_FS_ZIP */

/* data.c */
struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr);

int erofs_map_blocks(struct inode *, struct erofs_map_blocks *, int);

/* inode.c */
static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
{
#if BITS_PER_LONG == 32
	return (nid >> 32) ^ (nid & 0xffffffff);
#else
	return nid;
#endif
}

extern const struct inode_operations erofs_generic_iops;
extern const struct inode_operations erofs_symlink_iops;
extern const struct inode_operations erofs_fast_symlink_iops;

struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir);
int erofs_getattr(const struct path *path, struct kstat *stat,
		  u32 request_mask, unsigned int query_flags);

/* namei.c */
extern const struct inode_operations erofs_dir_iops;

int erofs_namei(struct inode *dir, struct qstr *name,
		erofs_nid_t *nid, unsigned int *d_type);

/* dir.c */
extern const struct file_operations erofs_dir_fops;

/* utils.c / zdata.c */
struct page *erofs_allocpage(struct list_head *pool, gfp_t gfp);

#if (EROFS_PCPUBUF_NR_PAGES > 0)
void *erofs_get_pcpubuf(unsigned int pagenr);
#define erofs_put_pcpubuf(buf) do { \
	(void)&(buf);	\
	preempt_enable();	\
} while (0)
#else
static inline void *erofs_get_pcpubuf(unsigned int pagenr)
{
	return ERR_PTR(-EOPNOTSUPP);
}

#define erofs_put_pcpubuf(buf) do {} while (0)
#endif

#ifdef CONFIG_EROFS_FS_ZIP
int erofs_workgroup_put(struct erofs_workgroup *grp);
struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
					     pgoff_t index);
struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
					       struct erofs_workgroup *grp);
void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
void erofs_shrinker_register(struct super_block *sb);
void erofs_shrinker_unregister(struct super_block *sb);
int __init erofs_init_shrinker(void);
void erofs_exit_shrinker(void);
int __init z_erofs_init_zip_subsystem(void);
void z_erofs_exit_zip_subsystem(void);
int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
				       struct erofs_workgroup *egrp);
int erofs_try_to_free_cached_page(struct address_space *mapping,
				  struct page *page);
#else
static inline void erofs_shrinker_register(struct super_block *sb) {}
static inline void erofs_shrinker_unregister(struct super_block *sb) {}
static inline int erofs_init_shrinker(void) { return 0; }
static inline void erofs_exit_shrinker(void) {}
static inline int z_erofs_init_zip_subsystem(void) { return 0; }
static inline void z_erofs_exit_zip_subsystem(void) {}
#endif	/* !CONFIG_EROFS_FS_ZIP */

#define EFSCORRUPTED    EUCLEAN         /* Filesystem is corrupted */

#endif	/* __EROFS_INTERNAL_H */
Commit	Line	Data
29b24f6c GX	1	/* SPDX-License-Identifier: GPL-2.0-only */
29b24f6c GX	2	/*
bfb8674d GX	3	* Copyright (C) 2017-2018 HUAWEI, Inc.
	4	* http://www.huawei.com/
	5	* Created by Gao Xiang <gaoxiang25@huawei.com>
bfb8674d	6	*/
14f362b4 GX	7	#ifndef __EROFS_INTERNAL_H
14f362b4 GX	8	#define __EROFS_INTERNAL_H
bfb8674d GX	9
	10	#include <linux/fs.h>
	11	#include <linux/dcache.h>
	12	#include <linux/mm.h>
	13	#include <linux/pagemap.h>
	14	#include <linux/bio.h>
	15	#include <linux/buffer_head.h>
47e4937a	16	#include <linux/magic.h>
bfb8674d GX	17	#include <linux/slab.h>
	18	#include <linux/vmalloc.h>
	19	#include "erofs_fs.h"
	20
	21	/* redefine pr_fmt "erofs: " */
	22	#undef pr_fmt
	23	#define pr_fmt(fmt) "erofs: " fmt
	24
4f761fa2 GX	25	__printf(3, 4) void _erofs_err(struct super_block *sb,
	26	const char function, const char fmt, ...);
	27	#define erofs_err(sb, fmt, ...) \
	28	_erofs_err(sb, __func__, fmt "\n", ##__VA_ARGS__)
	29	__printf(3, 4) void _erofs_info(struct super_block *sb,
	30	const char function, const char fmt, ...);
	31	#define erofs_info(sb, fmt, ...) \
	32	_erofs_info(sb, __func__, fmt "\n", ##__VA_ARGS__)
bfb8674d	33	#ifdef CONFIG_EROFS_FS_DEBUG
4f761fa2	34	#define erofs_dbg(x, ...) pr_debug(x "\n", ##__VA_ARGS__)
bfb8674d GX	35	#define DBG_BUGON BUG_ON
bfb8674d GX	36	#else
4f761fa2	37	#define erofs_dbg(x, ...) ((void)0)
eef16878	38	#define DBG_BUGON(x) ((void)(x))
14f362b4	39	#endif /* !CONFIG_EROFS_FS_DEBUG */
bfb8674d GX	40
	41	/* EROFS_SUPER_MAGIC_V1 to represent the whole file system */
	42	#define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1
	43
	44	typedef u64 erofs_nid_t;
14f362b4 GX	45	typedef u64 erofs_off_t;
	46	/* data type for filesystem-wide blocks number */
	47	typedef u32 erofs_blk_t;
bfb8674d GX	48
bfb8674d GX	49	struct erofs_sb_info {
22fe04a7	50	#ifdef CONFIG_EROFS_FS_ZIP
2497ee41 GX	51	/* list for all registered superblocks, mainly for shrinker */
2497ee41 GX	52	struct list_head list;
a1581312	53	struct mutex umount_mutex;
2497ee41	54
64094a04 GX	55	/* managed XArray arranged in physical block number */
64094a04 GX	56	struct xarray managed_pslots;
105d4ad8	57
5fb76bb0 GX	58	/* threshold for decompression synchronously */
	59	unsigned int max_sync_decompress_pages;
	60
22fe04a7 GX	61	unsigned int shrinker_run_no;
22fe04a7 GX	62
4279f3f9 GX	63	/* current strategy of how to use managed cache */
4279f3f9 GX	64	unsigned char cache_strategy;
105d4ad8	65
4279f3f9 GX	66	/* pseudo inode to manage cached pages */
4279f3f9 GX	67	struct inode *managed_cache;
22fe04a7 GX	68	#endif /* CONFIG_EROFS_FS_ZIP */
	69	u32 blocks;
	70	u32 meta_blkaddr;
	71	#ifdef CONFIG_EROFS_FS_XATTR
	72	u32 xattr_blkaddr;
02827e17	73	#endif
bfb8674d	74
22fe04a7 GX	75	/* inode slot unit size in bit shift */
	76	unsigned char islotbits;
	77
bfb8674d GX	78	u32 build_time_nsec;
	79	u64 build_time;
	80
	81	/* what we really care is nid, rather than ino.. */
	82	erofs_nid_t root_nid;
	83	/* used for statfs, f_files - f_favail */
	84	u64 inos;
	85
	86	u8 uuid[16]; /* 128-bit uuid for volume */
	87	u8 volume_name[16]; /* volume name */
b858a484	88	u32 feature_compat;
426a9308	89	u32 feature_incompat;
5efe5137	90
bfb8674d GX	91	unsigned int mount_opt;
	92	};
	93
	94	#define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
	95	#define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
	96
b17500a0 GX	97	/* Mount flags set via mount options or defaults */
	98	#define EROFS_MOUNT_XATTR_USER 0x00000010
	99	#define EROFS_MOUNT_POSIX_ACL 0x00000020
	100
bfb8674d GX	101	#define clear_opt(sbi, option) ((sbi)->mount_opt &= ~EROFS_MOUNT_##option)
	102	#define set_opt(sbi, option) ((sbi)->mount_opt \|= EROFS_MOUNT_##option)
	103	#define test_opt(sbi, option) ((sbi)->mount_opt & EROFS_MOUNT_##option)
	104
e7e9a307	105	#ifdef CONFIG_EROFS_FS_ZIP
4279f3f9 GX	106	enum {
	107	EROFS_ZIP_CACHE_DISABLED,
	108	EROFS_ZIP_CACHE_READAHEAD,
	109	EROFS_ZIP_CACHE_READAROUND
	110	};
	111
14f362b4 GX	112	#define EROFS_LOCKED_MAGIC (INT_MIN \| 0xE0F510CCL)
14f362b4 GX	113
e7e9a307 GX	114	/* basic unit of the workstation of a super_block */
	115	struct erofs_workgroup {
	116	/* the workgroup index in the workstation */
	117	pgoff_t index;
	118
	119	/* overall workgroup reference count */
	120	atomic_t refcount;
	121	};
	122
73f5c66d GX	123	#if defined(CONFIG_SMP)
	124	static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
	125	int val)
e7e9a307	126	{
e7e9a307	127	preempt_disable();
73f5c66d	128	if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
e7e9a307 GX	129	preempt_enable();
	130	return false;
	131	}
e7e9a307 GX	132	return true;
	133	}
	134
73f5c66d GX	135	static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
73f5c66d GX	136	int orig_val)
e7e9a307	137	{
948bbdb1 GX	138	/*
	139	* other observers should notice all modifications
	140	* in the freezing period.
	141	*/
	142	smp_mb();
73f5c66d	143	atomic_set(&grp->refcount, orig_val);
e7e9a307 GX	144	preempt_enable();
	145	}
	146
df134b8d GX	147	static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
	148	{
	149	return atomic_cond_read_relaxed(&grp->refcount,
	150	VAL != EROFS_LOCKED_MAGIC);
	151	}
	152	#else
73f5c66d GX	153	static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
	154	int val)
	155	{
	156	preempt_disable();
	157	/* no need to spin on UP platforms, let's just disable preemption. */
	158	if (val != atomic_read(&grp->refcount)) {
	159	preempt_enable();
	160	return false;
	161	}
	162	return true;
	163	}
	164
	165	static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
	166	int orig_val)
	167	{
	168	preempt_enable();
	169	}
	170
df134b8d GX	171	static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
	172	{
	173	int v = atomic_read(&grp->refcount);
	174
	175	/* workgroup is never freezed on uniprocessor systems */
	176	DBG_BUGON(v == EROFS_LOCKED_MAGIC);
	177	return v;
	178	}
14f362b4	179	#endif /* !CONFIG_SMP */
105d4ad8	180
14f362b4 GX	181	/* hard limit of pages per compressed cluster */
	182	#define Z_EROFS_CLUSTER_MAX_PAGES (CONFIG_EROFS_FS_CLUSTER_PAGE_LIMIT)
	183	#define EROFS_PCPUBUF_NR_PAGES Z_EROFS_CLUSTER_MAX_PAGES
0a0b7e62	184	#else
14f362b4	185	#define EROFS_PCPUBUF_NR_PAGES 0
14f362b4	186	#endif /* !CONFIG_EROFS_FS_ZIP */
e7e9a307	187
bfb8674d GX	188	/* we strictly follow PAGE_SIZE and no buffer head yet */
	189	#define LOG_BLOCK_SIZE PAGE_SHIFT
	190
	191	#undef LOG_SECTORS_PER_BLOCK
	192	#define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9)
	193
	194	#undef SECTORS_PER_BLOCK
	195	#define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK)
	196
	197	#define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE)
	198
	199	#if (EROFS_BLKSIZ % 4096 \|\| !EROFS_BLKSIZ)
	200	#error erofs cannot be used in this platform
	201	#endif
	202
	203	#define ROOT_NID(sb) ((sb)->root_nid)
	204
bfb8674d GX	205	#define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ)
	206	#define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ)
	207	#define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ)
	208
	209	static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid)
	210	{
	211	return blknr_to_addr(sbi->meta_blkaddr) + (nid << sbi->islotbits);
	212	}
	213
62dc4597	214	/* atomic flag definitions */
a5876e24 GX	215	#define EROFS_I_EA_INITED_BIT 0
a5876e24 GX	216	#define EROFS_I_Z_INITED_BIT 1
62dc4597 GX	217
62dc4597 GX	218	/* bitlock definitions (arranged in reverse order) */
a5876e24 GX	219	#define EROFS_I_BL_XATTR_BIT (BITS_PER_LONG - 1)
a5876e24 GX	220	#define EROFS_I_BL_Z_BIT (BITS_PER_LONG - 2)
bfb8674d	221
a5876e24	222	struct erofs_inode {
bfb8674d	223	erofs_nid_t nid;
62dc4597 GX	224
	225	/* atomic flags (including bitlocks) */
	226	unsigned long flags;
bfb8674d	227
8a765682	228	unsigned char datalayout;
bfb8674d GX	229	unsigned char inode_isize;
	230	unsigned short xattr_isize;
	231
e82a9a17 PS	232	unsigned int xattr_shared_count;
e82a9a17 PS	233	unsigned int *xattr_shared_xattrs;
bfb8674d	234
152a333a GX	235	union {
	236	erofs_blk_t raw_blkaddr;
	237	#ifdef CONFIG_EROFS_FS_ZIP
	238	struct {
	239	unsigned short z_advise;
	240	unsigned char z_algorithmtype[2];
	241	unsigned char z_logical_clusterbits;
	242	unsigned char z_physical_clusterbits[2];
	243	};
14f362b4	244	#endif /* CONFIG_EROFS_FS_ZIP */
152a333a	245	};
bfb8674d GX	246	/* the corresponding vfs inode */
	247	struct inode vfs_inode;
	248	};
	249
a5876e24 GX	250	#define EROFS_I(ptr) \
a5876e24 GX	251	container_of(ptr, struct erofs_inode, vfs_inode)
bfb8674d	252
99634bf3	253	static inline unsigned long erofs_inode_datablocks(struct inode *inode)
bfb8674d GX	254	{
	255	/* since i_size cannot be changed */
	256	return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ);
	257	}
	258
8a765682 GX	259	static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
	260	unsigned int bits)
	261	{
	262
	263	return (value >> bit) & ((1 << bits) - 1);
	264	}
	265
	266
	267	static inline unsigned int erofs_inode_version(unsigned int value)
bfb8674d	268	{
8a765682 GX	269	return erofs_bitrange(value, EROFS_I_VERSION_BIT,
8a765682 GX	270	EROFS_I_VERSION_BITS);
bfb8674d GX	271	}
bfb8674d GX	272
8a765682	273	static inline unsigned int erofs_inode_datalayout(unsigned int value)
bfb8674d	274	{
8a765682 GX	275	return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
8a765682 GX	276	EROFS_I_DATALAYOUT_BITS);
bfb8674d GX	277	}
	278
	279	extern const struct super_operations erofs_sops;
bfb8674d GX	280
bfb8674d GX	281	extern const struct address_space_operations erofs_raw_access_aops;
0c638f70	282	extern const struct address_space_operations z_erofs_aops;
bfb8674d GX	283
	284	/*
	285	* Logical to physical block mapping, used by erofs_map_blocks()
	286	*
	287	* Different with other file systems, it is used for 2 access modes:
	288	*
	289	* 1) RAW access mode:
	290	*
	291	* Users pass a valid (m_lblk, m_lofs -- usually 0) pair,
	292	* and get the valid m_pblk, m_pofs and the longest m_len(in bytes).
	293	*
	294	* Note that m_lblk in the RAW access mode refers to the number of
	295	* the compressed ondisk block rather than the uncompressed
	296	* in-memory block for the compressed file.
	297	*
	298	* m_pofs equals to m_lofs except for the inline data page.
	299	*
	300	* 2) Normal access mode:
	301	*
	302	* If the inode is not compressed, it has no difference with
	303	* the RAW access mode. However, if the inode is compressed,
	304	* users should pass a valid (m_lblk, m_lofs) pair, and get
	305	* the needed m_pblk, m_pofs, m_len to get the compressed data
	306	* and the updated m_lblk, m_lofs which indicates the start
	307	* of the corresponding uncompressed data in the file.
	308	*/
	309	enum {
	310	BH_Zipped = BH_PrivateStart,
b6a76183	311	BH_FullMapped,
bfb8674d GX	312	};
	313
	314	/* Has a disk mapping */
	315	#define EROFS_MAP_MAPPED (1 << BH_Mapped)
	316	/* Located in metadata (could be copied from bd_inode) */
	317	#define EROFS_MAP_META (1 << BH_Meta)
	318	/* The extent has been compressed */
	319	#define EROFS_MAP_ZIPPED (1 << BH_Zipped)
b6a76183 GX	320	/* The length of extent is full */
b6a76183 GX	321	#define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped)
bfb8674d GX	322
	323	struct erofs_map_blocks {
	324	erofs_off_t m_pa, m_la;
	325	u64 m_plen, m_llen;
	326
	327	unsigned int m_flags;
3b423417 CY	328
3b423417 CY	329	struct page *mpage;
bfb8674d GX	330	};
	331
	332	/* Flags used by erofs_map_blocks() */
	333	#define EROFS_GET_BLOCKS_RAW 0x0001
	334
152a333a	335	/* zmap.c */
3b423417	336	#ifdef CONFIG_EROFS_FS_ZIP
152a333a	337	int z_erofs_fill_inode(struct inode *inode);
3b423417 CY	338	int z_erofs_map_blocks_iter(struct inode *inode,
	339	struct erofs_map_blocks *map,
	340	int flags);
	341	#else
ff784a78	342	static inline int z_erofs_fill_inode(struct inode *inode) { return -EOPNOTSUPP; }
3b423417 CY	343	static inline int z_erofs_map_blocks_iter(struct inode *inode,
	344	struct erofs_map_blocks *map,
	345	int flags)
	346	{
ff784a78	347	return -EOPNOTSUPP;
3b423417	348	}
14f362b4	349	#endif /* !CONFIG_EROFS_FS_ZIP */
3b423417	350
bfb8674d	351	/* data.c */
e655b5b3	352	struct page erofs_get_meta_page(struct super_block sb, erofs_blk_t blkaddr);
6e78901a	353
2e1d6637	354	int erofs_map_blocks(struct inode , struct erofs_map_blocks , int);
bfb8674d	355
bfb8674d	356	/* inode.c */
2abd7814 GX	357	static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
	358	{
	359	#if BITS_PER_LONG == 32
	360	return (nid >> 32) ^ (nid & 0xffffffff);
	361	#else
	362	return nid;
	363	#endif
	364	}
	365
60939826 GX	366	extern const struct inode_operations erofs_generic_iops;
	367	extern const struct inode_operations erofs_symlink_iops;
	368	extern const struct inode_operations erofs_fast_symlink_iops;
b17500a0	369
2e1d6637	370	struct inode erofs_iget(struct super_block sb, erofs_nid_t nid, bool dir);
89f27ede GX	371	int erofs_getattr(const struct path path, struct kstat stat,
89f27ede GX	372	u32 request_mask, unsigned int query_flags);
2e1d6637	373
60939826 GX	374	/* namei.c */
	375	extern const struct inode_operations erofs_dir_iops;
	376
	377	int erofs_namei(struct inode dir, struct qstr name,
	378	erofs_nid_t nid, unsigned int d_type);
	379
	380	/* dir.c */
	381	extern const struct file_operations erofs_dir_fops;
	382
14f362b4	383	/* utils.c / zdata.c */
5ddcee1f	384	struct page erofs_allocpage(struct list_head pool, gfp_t gfp);
fa61a33f GX	385
	386	#if (EROFS_PCPUBUF_NR_PAGES > 0)
	387	void *erofs_get_pcpubuf(unsigned int pagenr);
	388	#define erofs_put_pcpubuf(buf) do { \
	389	(void)&(buf); \
	390	preempt_enable(); \
	391	} while (0)
	392	#else
	393	static inline void *erofs_get_pcpubuf(unsigned int pagenr)
	394	{
ff784a78	395	return ERR_PTR(-EOPNOTSUPP);
fa61a33f GX	396	}
	397
	398	#define erofs_put_pcpubuf(buf) do {} while (0)
	399	#endif
	400
22fe04a7	401	#ifdef CONFIG_EROFS_FS_ZIP
14f362b4 GX	402	int erofs_workgroup_put(struct erofs_workgroup *grp);
14f362b4 GX	403	struct erofs_workgroup erofs_find_workgroup(struct super_block sb,
997626d8	404	pgoff_t index);
64094a04 GX	405	struct erofs_workgroup erofs_insert_workgroup(struct super_block sb,
64094a04 GX	406	struct erofs_workgroup *grp);
14f362b4	407	void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
22fe04a7 GX	408	void erofs_shrinker_register(struct super_block *sb);
	409	void erofs_shrinker_unregister(struct super_block *sb);
	410	int __init erofs_init_shrinker(void);
	411	void erofs_exit_shrinker(void);
	412	int __init z_erofs_init_zip_subsystem(void);
	413	void z_erofs_exit_zip_subsystem(void);
14f362b4 GX	414	int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
	415	struct erofs_workgroup *egrp);
	416	int erofs_try_to_free_cached_page(struct address_space *mapping,
	417	struct page *page);
22fe04a7 GX	418	#else
	419	static inline void erofs_shrinker_register(struct super_block *sb) {}
	420	static inline void erofs_shrinker_unregister(struct super_block *sb) {}
	421	static inline int erofs_init_shrinker(void) { return 0; }
	422	static inline void erofs_exit_shrinker(void) {}
	423	static inline int z_erofs_init_zip_subsystem(void) { return 0; }
	424	static inline void z_erofs_exit_zip_subsystem(void) {}
	425	#endif /* !CONFIG_EROFS_FS_ZIP */
2e1d6637	426
a6b9b1d5 GX	427	#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
a6b9b1d5 GX	428
14f362b4	429	#endif /* __EROFS_INTERNAL_H */
bfb8674d	430