diff options
| -rw-r--r-- | MAINTAINERS | 1 | ||||
| -rw-r--r-- | fs/Makefile | 3 | ||||
| -rw-r--r-- | fs/fs_types.c | 105 | ||||
| -rw-r--r-- | include/linux/fs.h | 17 | ||||
| -rw-r--r-- | include/linux/fs_types.h | 75 |
5 files changed, 184 insertions, 17 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 51029a425dbe..0afaaf0aa6be 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5881,6 +5881,7 @@ L: linux-fsdevel@vger.kernel.org S: Maintained F: fs/* F: include/linux/fs.h +F: include/linux/fs_types.h F: include/uapi/linux/fs.h FINTEK F75375S HARDWARE MONITOR AND FAN CONTROLLER DRIVER diff --git a/fs/Makefile b/fs/Makefile index 293733f61594..23fcd8c164a3 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -12,7 +12,8 @@ obj-y := open.o read_write.o file_table.o super.o \ attr.o bad_inode.o file.o filesystems.o namespace.o \ seq_file.o xattr.o libfs.o fs-writeback.o \ pnode.o splice.o sync.o utimes.o d_path.o \ - stack.o fs_struct.o statfs.o fs_pin.o nsfs.o + stack.o fs_struct.o statfs.o fs_pin.o nsfs.o \ + fs_types.o ifeq ($(CONFIG_BLOCK),y) obj-y += buffer.o block_dev.o direct-io.o mpage.o diff --git a/fs/fs_types.c b/fs/fs_types.c new file mode 100644 index 000000000000..78365e5dc08c --- /dev/null +++ b/fs/fs_types.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/fs.h> +#include <linux/export.h> + +/* + * fs on-disk file type to dirent file type conversion + */ +static const unsigned char fs_dtype_by_ftype[FT_MAX] = { + [FT_UNKNOWN] = DT_UNKNOWN, + [FT_REG_FILE] = DT_REG, + [FT_DIR] = DT_DIR, + [FT_CHRDEV] = DT_CHR, + [FT_BLKDEV] = DT_BLK, + [FT_FIFO] = DT_FIFO, + [FT_SOCK] = DT_SOCK, + [FT_SYMLINK] = DT_LNK +}; + +/** + * fs_ftype_to_dtype() - fs on-disk file type to dirent type. + * @filetype: The on-disk file type to convert. + * + * This function converts the on-disk file type value (FT_*) to the directory + * entry type (DT_*). + * + * Context: Any context. + * Return: + * * DT_UNKNOWN - Unknown type + * * DT_FIFO - FIFO + * * DT_CHR - Character device + * * DT_DIR - Directory + * * DT_BLK - Block device + * * DT_REG - Regular file + * * DT_LNK - Symbolic link + * * DT_SOCK - Local-domain socket + */ +unsigned char fs_ftype_to_dtype(unsigned int filetype) +{ + if (filetype >= FT_MAX) + return DT_UNKNOWN; + + return fs_dtype_by_ftype[filetype]; +} +EXPORT_SYMBOL_GPL(fs_ftype_to_dtype); + +/* + * dirent file type to fs on-disk file type conversion + * Values not initialized explicitly are FT_UNKNOWN (0). + */ +static const unsigned char fs_ftype_by_dtype[DT_MAX] = { + [DT_REG] = FT_REG_FILE, + [DT_DIR] = FT_DIR, + [DT_LNK] = FT_SYMLINK, + [DT_CHR] = FT_CHRDEV, + [DT_BLK] = FT_BLKDEV, + [DT_FIFO] = FT_FIFO, + [DT_SOCK] = FT_SOCK, +}; + +/** + * fs_umode_to_ftype() - file mode to on-disk file type. + * @mode: The file mode to convert. + * + * This function converts the file mode value to the on-disk file type (FT_*). + * + * Context: Any context. + * Return: + * * FT_UNKNOWN - Unknown type + * * FT_REG_FILE - Regular file + * * FT_DIR - Directory + * * FT_CHRDEV - Character device + * * FT_BLKDEV - Block device + * * FT_FIFO - FIFO + * * FT_SOCK - Local-domain socket + * * FT_SYMLINK - Symbolic link + */ +unsigned char fs_umode_to_ftype(umode_t mode) +{ + return fs_ftype_by_dtype[S_DT(mode)]; +} +EXPORT_SYMBOL_GPL(fs_umode_to_ftype); + +/** + * fs_umode_to_dtype() - file mode to dirent file type. + * @mode: The file mode to convert. + * + * This function converts the file mode value to the directory + * entry type (DT_*). + * + * Context: Any context. + * Return: + * * DT_UNKNOWN - Unknown type + * * DT_FIFO - FIFO + * * DT_CHR - Character device + * * DT_DIR - Directory + * * DT_BLK - Block device + * * DT_REG - Regular file + * * DT_LNK - Symbolic link + * * DT_SOCK - Local-domain socket + */ +unsigned char fs_umode_to_dtype(umode_t mode) +{ + return fs_ftype_to_dtype(fs_umode_to_ftype(mode)); +} +EXPORT_SYMBOL_GPL(fs_umode_to_dtype); diff --git a/include/linux/fs.h b/include/linux/fs.h index 811c77743dad..92966678539d 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> @@ -1700,22 +1701,6 @@ 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 |