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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2017-2018 HUAWEI, Inc.
* https://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_fs_context {
#ifdef CONFIG_EROFS_FS_ZIP
/* current strategy of how to use managed cache */
unsigned char cache_strategy;
/* threshold for decompression synchronously */
unsigned int max_sync_decompress_pages;
#endif
unsigned int mount_opt;
};
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;
unsigned int shrinker_run_no;
/* 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;
struct erofs_fs_context ctx; /* options */
};
#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(ctx, option) ((ctx)->mount_opt &= ~EROFS_MOUNT_##option)
#define set_opt(ctx, option) ((ctx)->mount_opt |= EROFS_MOUNT_##option)
#define test_opt(ctx, option) ((ctx)->mount_opt & EROFS_MOUNT_##option)
enum {
EROFS_ZIP_CACHE_DISABLED,
EROFS_ZIP_CACHE_READAHEAD,
EROFS_ZIP_CACHE_READAROUND
};
#ifdef CONFIG_EROFS_FS_ZIP
#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(struct user_namespace *mnt_userns, 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 */