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Diffstat (limited to 'fs/erofs/internal.h')
| -rw-r--r-- | fs/erofs/internal.h | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h new file mode 100644 index 000000000000..544a453f3076 --- /dev/null +++ b/fs/erofs/internal.h @@ -0,0 +1,431 @@ +/* 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; + + /* the dedicated workstation for compression */ + struct radix_tree_root workstn_tree; + + /* 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_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; +#ifdef CONFIG_EROFS_FS_ZIP +extern const struct address_space_operations z_erofs_vle_normalaccess_aops; +#endif + +/* + * 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, bool nofail); + +#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, bool *tag); +int erofs_register_workgroup(struct super_block *sb, + struct erofs_workgroup *grp, bool tag); +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 */ + |