Loading...
/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_FS_TYPES_H #define _LINUX_FS_TYPES_H /* * This is a header for the common implementation of dirent * to fs on-disk file type conversion. Although the fs on-disk * bits are specific to every file system, in practice, many * file systems use the exact same on-disk format to describe * the lower 3 file type bits that represent the 7 POSIX file * types. * * It is important to note that the definitions in this * header MUST NOT change. This would break both the * userspace ABI and the on-disk format of filesystems * using this code. * * All those file systems can use this generic code for the * conversions. */ /* * struct dirent file types * exposed to user via getdents(2), readdir(3) * * These match bits 12..15 of stat.st_mode * (ie "(i_mode >> 12) & 15"). */ #define S_DT_SHIFT 12 #define S_DT(mode) (((mode) & S_IFMT) >> S_DT_SHIFT) #define S_DT_MASK (S_IFMT >> S_DT_SHIFT) /* these are defined by POSIX and also present in glibc's dirent.h */ #define DT_UNKNOWN 0 #define DT_FIFO 1 #define DT_CHR 2 #define DT_DIR 4 #define DT_BLK 6 #define DT_REG 8 #define DT_LNK 10 #define DT_SOCK 12 #define DT_WHT 14 #define DT_MAX (S_DT_MASK + 1) /* 16 */ /* * fs on-disk file types. * Only the low 3 bits are used for the POSIX file types. * Other bits are reserved for fs private use. * These definitions are shared and used by multiple filesystems, * and MUST NOT change under any circumstances. * * Note that no fs currently stores the whiteout type on-disk, * so whiteout dirents are exposed to user as DT_CHR. */ #define FT_UNKNOWN 0 #define FT_REG_FILE 1 #define FT_DIR 2 #define FT_CHRDEV 3 #define FT_BLKDEV 4 #define FT_FIFO 5 #define FT_SOCK 6 #define FT_SYMLINK 7 #define FT_MAX 8 /* * declarations for helper functions, accompanying implementation * is in fs/fs_types.c */ extern unsigned char fs_ftype_to_dtype(unsigned int filetype); extern unsigned char fs_umode_to_ftype(umode_t mode); extern unsigned char fs_umode_to_dtype(umode_t mode); #endif |