- erofs_sb_info: contains erofs-specific in-memory information. - erofs_vnode: contains vfs_inode and other fs-specific information. same as super block, the only one in-memory definition exists. - erofs_map_blocks plays a role in the disk L2P mapping Signed-off-by: Miao Xie <miaoxie@xxxxxxxxxx> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx> Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx> --- fs/erofs/internal.h | 300 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 300 insertions(+) create mode 100644 fs/erofs/internal.h diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h new file mode 100644 index 0000000..2a3cd45 --- /dev/null +++ b/fs/erofs/internal.h @@ -0,0 +1,300 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * linux/fs/erofs/internal.h + * + * Copyright (C) 2017-2018 HUAWEI, Inc. + * http://www.huawei.com/ + * Created by Gao Xiang <gaoxiang25@xxxxxxxxxx> + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of the Linux + * distribution for more details. + */ +#ifndef __INTERNAL_H +#define __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/cleancache.h> +#include <linux/vmalloc.h> +#include "erofs_fs.h" + +#include "staging.h" + +/* redefine pr_fmt "erofs: " */ +#undef pr_fmt +#define pr_fmt(fmt) "erofs: " fmt + +#define errln(x, ...) pr_err(x "\n", ##__VA_ARGS__) +#define infoln(x, ...) pr_info(x "\n", ##__VA_ARGS__) +#ifdef CONFIG_EROFS_FS_DEBUG +#define debugln(x, ...) pr_debug(x "\n", ##__VA_ARGS__) + +#define erofs_dbg_might_sleep might_sleep +#define DBG_BUGON BUG_ON +#else +#define debugln(x, ...) ((void)0) +#define erofs_dbg_might_sleep() ((void)0) +#define DBG_BUGON(...) ((void)0) +#endif + +/* EROFS_SUPER_MAGIC_V1 to represent the whole file system */ +#define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1 + +typedef u64 erofs_nid_t; + +struct erofs_sb_info { + u32 blocks; + u32 meta_blkaddr; + + /* 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 */ + char *dev_name; + + 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) + +#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) + +/* we strictly follow PAGE_SIZE and no buffer head */ +#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) + +typedef u64 erofs_off_t; + +/* data type for filesystem-wide blocks number */ +typedef u32 erofs_blk_t; + +static inline erofs_off_t iloc(struct erofs_sb_info *sbi, erofs_nid_t nid) +{ + return sbi->meta_blkaddr * EROFS_BLKSIZ + (nid << sbi->islotbits); +} + +#define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ) +#define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ) +#define blknr_to_addr(nr) ((nr) * EROFS_BLKSIZ) + +#define inode_set_inited_xattr(inode) (EROFS_V(inode)->flags |= 1) +#define inode_has_inited_xattr(inode) (EROFS_V(inode)->flags & 1) + +struct erofs_vnode { + erofs_nid_t nid; + unsigned int flags; + + unsigned char data_mapping_mode; + /* inline size in bytes */ + unsigned char inode_isize; + unsigned short xattr_isize; + +#if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 2, 0)) + char *i_link; +#endif + unsigned xattr_shared_count; + unsigned *xattr_shared_xattrs; + + erofs_blk_t raw_blkaddr; + + /* the corresponding vfs inode */ + struct inode vfs_inode; +}; + +#define EROFS_V(ptr) \ + container_of(ptr, struct erofs_vnode, vfs_inode) + +#define __inode_advise(x, bit, bits) \ + (((x) >> (bit)) & ((1 << (bits)) - 1)) + +#define __inode_version(advise) \ + __inode_advise(advise, EROFS_I_VERSION_BIT, \ + EROFS_I_VERSION_BITS) + +#define __inode_data_mapping(advise) \ + __inode_advise(advise, EROFS_I_DATA_MAPPING_BIT,\ + EROFS_I_DATA_MAPPING_BITS) + +static inline unsigned long inode_datablocks(struct inode *inode) +{ + /* since i_size cannot be changed */ + return DIV_ROUND_UP(inode->i_size, EROFS_BLKSIZ); +} + +static inline bool is_inode_layout_plain(struct inode *inode) +{ + return EROFS_V(inode)->data_mapping_mode == EROFS_INODE_LAYOUT_PLAIN; +} + +static inline bool is_inode_layout_compression(struct inode *inode) +{ + return EROFS_V(inode)->data_mapping_mode == + EROFS_INODE_LAYOUT_COMPRESSION; +} + +static inline bool is_inode_layout_inline(struct inode *inode) +{ + return EROFS_V(inode)->data_mapping_mode == EROFS_INODE_LAYOUT_INLINE; +} + +extern const struct super_operations erofs_sops; +extern const struct inode_operations erofs_dir_iops; +extern const struct file_operations erofs_dir_fops; + +extern const struct file_operations erofs_unaligned_compressed_fops; + +extern const struct address_space_operations erofs_raw_access_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, +}; + +/* 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) + +struct erofs_map_blocks { + erofs_off_t m_pa, m_la; + u64 m_plen, m_llen; + + unsigned int m_flags; +}; + +/* Flags used by erofs_map_blocks() */ +#define EROFS_GET_BLOCKS_RAW 0x0001 + +/* data.c */ +extern struct page *erofs_get_meta_page(struct super_block *sb, + erofs_blk_t blkaddr, bool prio); +extern int erofs_map_blocks(struct inode *, struct erofs_map_blocks *, int); +extern int erofs_map_blocks_iter(struct inode *, struct erofs_map_blocks *, + struct page **, int); + +struct erofs_map_blocks_iter { + struct erofs_map_blocks map; + struct page *mpage; +}; + + +static inline struct page *erofs_get_inline_page(struct inode *inode, + erofs_blk_t blkaddr) +{ + return erofs_get_meta_page(inode->i_sb, + blkaddr, S_ISDIR(inode->i_mode)); +} + +/* inode.c */ +extern struct inode *erofs_iget(struct super_block *sb, + erofs_nid_t nid, bool dir); + +/* dir.c */ +int erofs_namei(struct inode *dir, struct qstr *name, + erofs_nid_t *nid, unsigned *d_type); + +/* xattr.c */ +extern const struct xattr_handler *erofs_xattr_handlers[]; + +extern void test_meta_ops(struct super_block *sb); + +/* symlink */ +#if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 2, 0)) +extern const struct inode_operations simple_symlink_inode_operations; +#endif + +static inline void set_inode_fast_symlink(struct inode *inode) +{ + inode->i_op = &simple_symlink_inode_operations; +} + +static inline bool is_inode_fast_symlink(struct inode *inode) +{ + return inode->i_op == &simple_symlink_inode_operations; +} + +static inline void *erofs_vmap(struct page **pages, unsigned int count) +{ +#ifdef CONFIG_EROFS_FS_USE_VM_MAP_RAM + int i = 0; + + while (1) { + void *addr = vm_map_ram(pages, count, -1, PAGE_KERNEL); + /* retry two more times (totally 3 times) */ + if (addr != NULL || ++i >= 3) + return addr; + vm_unmap_aliases(); + } + return NULL; +#else + return vmap(pages, count, VM_MAP, PAGE_KERNEL); +#endif +} + +static inline void erofs_vunmap(const void *mem, unsigned int count) +{ +#ifdef CONFIG_EROFS_FS_USE_VM_MAP_RAM + vm_unmap_ram(mem, count); +#else + vunmap(mem); +#endif +} + +#endif + -- 1.9.1
