diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/fs.h | 17 | ||||
-rw-r--r-- | include/linux/fs_types.h | 75 |
2 files changed, 76 insertions, 16 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 08f26046233e..4ede9ffa362a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -37,6 +37,7 @@ #include <linux/uuid.h> #include <linux/errseq.h> #include <linux/ioprio.h> +#include <linux/fs_types.h> #include <asm/byteorder.h> #include <uapi/linux/fs.h> @@ -1707,22 +1708,6 @@ int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical, int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); /* - * File types - * - * NOTE! These match bits 12..15 of stat.st_mode - * (ie "(i_mode >> 12) & 15"). - */ -#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 - -/* * This is the "filldir" function type, used by readdir() to let * the kernel specify what kind of dirent layout it wants to have. * This allows the kernel to read directories into kernel space or diff --git a/include/linux/fs_types.h b/include/linux/fs_types.h new file mode 100644 index 000000000000..54816791196f --- /dev/null +++ b/include/linux/fs_types.h @@ -0,0 +1,75 @@ +/* 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 |