fuse_kernel.h

/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) */
/*
    This file defines the kernel interface of FUSE
    Copyright (C) 2001-2008  Miklos Szeredi <miklos@szeredi.hu>

    This program can be distributed under the terms of the GNU GPL.
    See the file COPYING.

    This -- and only this -- header file may also be distributed under
    the terms of the BSD Licence as follows:

    Copyright (C) 2001-2007 Miklos Szeredi. All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:
    1. Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.
    2. Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in the
       documentation and/or other materials provided with the distribution.

    THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    SUCH DAMAGE.
*/

/*
 * This file defines the kernel interface of FUSE
 *
 * Protocol changelog:
 *
 * 7.9:
 *  - new fuse_getattr_in input argument of GETATTR
 *  - add lk_flags in fuse_lk_in
 *  - add lock_owner field to fuse_setattr_in, fuse_read_in and fuse_write_in
 *  - add blksize field to fuse_attr
 *  - add file flags field to fuse_read_in and fuse_write_in
 *
 * 7.10
 *  - add nonseekable open flag
 *
 * 7.11
 *  - add IOCTL message
 *  - add unsolicited notification support
 *  - add POLL message and NOTIFY_POLL notification
 *
 * 7.12
 *  - add umask flag to input argument of open, mknod and mkdir
 *  - add notification messages for invalidation of inodes and
 *    directory entries
 *
 * 7.13
 *  - make max number of background requests and congestion threshold
 *    tunables
 *
 * 7.14
 *  - add splice support to fuse device
 *
 * 7.15
 *  - add store notify
 *  - add retrieve notify
 *
 * 7.16
 *  - add BATCH_FORGET request
 *  - FUSE_IOCTL_UNRESTRICTED shall now return with array of 'struct
 *    fuse_ioctl_iovec' instead of ambiguous 'struct iovec'
 *  - add FUSE_IOCTL_32BIT flag
 *
 * 7.17
 *  - add FUSE_FLOCK_LOCKS and FUSE_RELEASE_FLOCK_UNLOCK
 *
 * 7.18
 *  - add FUSE_IOCTL_DIR flag
 *  - add FUSE_NOTIFY_DELETE
 *
 * 7.19
 *  - add FUSE_FALLOCATE
 *
 * 7.20
 *  - add FUSE_AUTO_INVAL_DATA
 *
 * 7.21
 *  - add FUSE_READDIRPLUS
 *  - send the requested events in POLL request
 *
 * 7.22
 *  - add FUSE_ASYNC_DIO
 *
 * 7.23
 *  - add FUSE_WRITEBACK_CACHE
 *  - add time_gran to fuse_init_out
 *  - add reserved space to fuse_init_out
 *  - add FATTR_CTIME
 *  - add ctime and ctimensec to fuse_setattr_in
 *  - add FUSE_RENAME2 request
 *  - add FUSE_NO_OPEN_SUPPORT flag
 *
 *  7.24
 *  - add FUSE_LSEEK for SEEK_HOLE and SEEK_DATA support
 *
 *  7.25
 *  - add FUSE_PARALLEL_DIROPS
 *
 *  7.26
 *  - add FUSE_HANDLE_KILLPRIV
 *  - add FUSE_POSIX_ACL
 *
 *  7.27
 *  - add FUSE_ABORT_ERROR
 *
 *  7.28
 *  - add FUSE_COPY_FILE_RANGE
 */

#ifndef _LINUX_FUSE_H
#define _LINUX_FUSE_H

#ifdef __KERNEL__
#include <linux/types.h>
#else
#include <stdint.h>
#endif

/*
 * Version negotiation:
 *
 * Both the kernel and userspace send the version they support in the
 * INIT request and reply respectively.
 *
 * If the major versions match then both shall use the smallest
 * of the two minor versions for communication.
 *
 * If the kernel supports a larger major version, then userspace shall
 * reply with the major version it supports, ignore the rest of the
 * INIT message and expect a new INIT message from the kernel with a
 * matching major version.
 *
 * If the library supports a larger major version, then it shall fall
 * back to the major protocol version sent by the kernel for
 * communication and reply with that major version (and an arbitrary
 * supported minor version).
 */

#define FUSE_KERNEL_VERSION 7

#define FUSE_KERNEL_MINOR_VERSION 27

#define FUSE_ROOT_ID 1

/* Make sure all structures are padded to 64bit boundary, so 32bit
   userspace works under 64bit kernels */

struct fuse_attr {
        uint64_t        ino;
        uint64_t        size;
        uint64_t        blocks;
        uint64_t        atime;
        uint64_t        mtime;
        uint64_t        ctime;
        uint32_t        atimensec;
        uint32_t        mtimensec;
        uint32_t        ctimensec;
        uint32_t        mode;
        uint32_t        nlink;
        uint32_t        uid;
        uint32_t        gid;
        uint32_t        rdev;
        uint32_t        blksize;
        uint32_t        padding;
};

struct fuse_kstatfs {
        uint64_t        blocks;
        uint64_t        bfree;
        uint64_t        bavail;
        uint64_t        files;
        uint64_t        ffree;
        uint32_t        bsize;
        uint32_t        namelen;
        uint32_t        frsize;
        uint32_t        padding;
        uint32_t        spare[6];
};

struct fuse_file_lock {
        uint64_t        start;
        uint64_t        end;
        uint32_t        type;
        uint32_t        pid; /* tgid */
};

#define FATTR_MODE      (1 << 0)
#define FATTR_UID       (1 << 1)
#define FATTR_GID       (1 << 2)
#define FATTR_SIZE      (1 << 3)
#define FATTR_ATIME     (1 << 4)
#define FATTR_MTIME     (1 << 5)
#define FATTR_FH        (1 << 6)
#define FATTR_ATIME_NOW (1 << 7)
#define FATTR_MTIME_NOW (1 << 8)
#define FATTR_LOCKOWNER (1 << 9)
#define FATTR_CTIME     (1 << 10)

#define FOPEN_DIRECT_IO         (1 << 0)
#define FOPEN_KEEP_CACHE        (1 << 1)
#define FOPEN_NONSEEKABLE       (1 << 2)

#define FUSE_ASYNC_READ         (1 << 0)
#define FUSE_POSIX_LOCKS        (1 << 1)
#define FUSE_FILE_OPS           (1 << 2)
#define FUSE_ATOMIC_O_TRUNC     (1 << 3)
#define FUSE_EXPORT_SUPPORT     (1 << 4)
#define FUSE_BIG_WRITES         (1 << 5)
#define FUSE_DONT_MASK          (1 << 6)
#define FUSE_SPLICE_WRITE       (1 << 7)
#define FUSE_SPLICE_MOVE        (1 << 8)
#define FUSE_SPLICE_READ        (1 << 9)
#define FUSE_FLOCK_LOCKS        (1 << 10)
#define FUSE_HAS_IOCTL_DIR      (1 << 11)
#define FUSE_AUTO_INVAL_DATA    (1 << 12)
#define FUSE_DO_READDIRPLUS     (1 << 13)
#define FUSE_READDIRPLUS_AUTO   (1 << 14)
#define FUSE_ASYNC_DIO          (1 << 15)
#define FUSE_WRITEBACK_CACHE    (1 << 16)
#define FUSE_NO_OPEN_SUPPORT    (1 << 17)
#define FUSE_PARALLEL_DIROPS    (1 << 18)
#define FUSE_HANDLE_KILLPRIV    (1 << 19)
#define FUSE_POSIX_ACL          (1 << 20)
#define FUSE_ABORT_ERROR        (1 << 21)

#define CUSE_UNRESTRICTED_IOCTL (1 << 0)

#define FUSE_RELEASE_FLUSH      (1 << 0)
#define FUSE_RELEASE_FLOCK_UNLOCK       (1 << 1)

#define FUSE_GETATTR_FH         (1 << 0)

#define FUSE_LK_FLOCK           (1 << 0)

#define FUSE_WRITE_CACHE        (1 << 0)
#define FUSE_WRITE_LOCKOWNER    (1 << 1)

#define FUSE_READ_LOCKOWNER     (1 << 1)

#define FUSE_IOCTL_COMPAT       (1 << 0)
#define FUSE_IOCTL_UNRESTRICTED (1 << 1)
#define FUSE_IOCTL_RETRY        (1 << 2)
#define FUSE_IOCTL_32BIT        (1 << 3)
#define FUSE_IOCTL_DIR          (1 << 4)

#define FUSE_IOCTL_MAX_IOV      256

#define FUSE_POLL_SCHEDULE_NOTIFY (1 << 0)

enum fuse_opcode {
        FUSE_LOOKUP             = 1,
        FUSE_FORGET             = 2,  /* no reply */
        FUSE_GETATTR            = 3,
        FUSE_SETATTR            = 4,
        FUSE_READLINK           = 5,
        FUSE_SYMLINK            = 6,
        FUSE_MKNOD              = 8,
        FUSE_MKDIR              = 9,
        FUSE_UNLINK             = 10,
        FUSE_RMDIR              = 11,
        FUSE_RENAME             = 12,
        FUSE_LINK               = 13,
        FUSE_OPEN               = 14,
        FUSE_READ               = 15,
        FUSE_WRITE              = 16,
        FUSE_STATFS             = 17,
        FUSE_RELEASE            = 18,
        FUSE_FSYNC              = 20,
        FUSE_SETXATTR           = 21,
        FUSE_GETXATTR           = 22,
        FUSE_LISTXATTR          = 23,
        FUSE_REMOVEXATTR        = 24,
        FUSE_FLUSH              = 25,
        FUSE_INIT               = 26,
        FUSE_OPENDIR            = 27,
        FUSE_READDIR            = 28,
        FUSE_RELEASEDIR         = 29,
        FUSE_FSYNCDIR           = 30,
        FUSE_GETLK              = 31,
        FUSE_SETLK              = 32,
        FUSE_SETLKW             = 33,
        FUSE_ACCESS             = 34,
        FUSE_CREATE             = 35,
        FUSE_INTERRUPT          = 36,
        FUSE_BMAP               = 37,
        FUSE_DESTROY            = 38,
        FUSE_IOCTL              = 39,
        FUSE_POLL               = 40,
        FUSE_NOTIFY_REPLY       = 41,
        FUSE_BATCH_FORGET       = 42,
        FUSE_FALLOCATE          = 43,
        FUSE_READDIRPLUS        = 44,
        FUSE_RENAME2            = 45,
        FUSE_LSEEK              = 46,
        FUSE_COPY_FILE_RANGE    = 47,

        /* CUSE specific operations */
        CUSE_INIT               = 4096,
};

enum fuse_notify_code {
        FUSE_NOTIFY_POLL   = 1,
        FUSE_NOTIFY_INVAL_INODE = 2,
        FUSE_NOTIFY_INVAL_ENTRY = 3,
        FUSE_NOTIFY_STORE = 4,
        FUSE_NOTIFY_RETRIEVE = 5,
        FUSE_NOTIFY_DELETE = 6,
        FUSE_NOTIFY_CODE_MAX,
};

/* The read buffer is required to be at least 8k, but may be much larger */
#define FUSE_MIN_READ_BUFFER 8192

#define FUSE_COMPAT_ENTRY_OUT_SIZE 120

struct fuse_entry_out {
        uint64_t        nodeid;         /* Inode ID */
        uint64_t        generation;     /* Inode generation: nodeid:gen must
                                           be unique for the fs's lifetime */
        uint64_t        entry_valid;    /* Cache timeout for the name */
        uint64_t        attr_valid;     /* Cache timeout for the attributes */
        uint32_t        entry_valid_nsec;
        uint32_t        attr_valid_nsec;
        struct fuse_attr attr;
};

struct fuse_forget_in {
        uint64_t        nlookup;
};

struct fuse_forget_one {
        uint64_t        nodeid;
        uint64_t        nlookup;
};

struct fuse_batch_forget_in {
        uint32_t        count;
        uint32_t        dummy;
};

struct fuse_getattr_in {
        uint32_t        getattr_flags;
        uint32_t        dummy;
        uint64_t        fh;
};

#define FUSE_COMPAT_ATTR_OUT_SIZE 96

struct fuse_attr_out {
        uint64_t        attr_valid;     /* Cache timeout for the attributes */
        uint32_t        attr_valid_nsec;
        uint32_t        dummy;
        struct fuse_attr attr;
};

#define FUSE_COMPAT_MKNOD_IN_SIZE 8

struct fuse_mknod_in {
        uint32_t        mode;
        uint32_t        rdev;
        uint32_t        umask;
        uint32_t        padding;
};

struct fuse_mkdir_in {
        uint32_t        mode;
        uint32_t        umask;
};

struct fuse_rename_in {
        uint64_t        newdir;
};

struct fuse_rename2_in {
        uint64_t        newdir;
        uint32_t        flags;
        uint32_t        padding;
};

struct fuse_link_in {
        uint64_t        oldnodeid;
};

struct fuse_setattr_in {
        uint32_t        valid;
        uint32_t        padding;
        uint64_t        fh;
        uint64_t        size;
        uint64_t        lock_owner;
        uint64_t        atime;
        uint64_t        mtime;
        uint64_t        ctime;
        uint32_t        atimensec;
        uint32_t        mtimensec;
        uint32_t        ctimensec;
        uint32_t        mode;
        uint32_t        unused4;
        uint32_t        uid;
        uint32_t        gid;
        uint32_t        unused5;
};

struct fuse_open_in {
        uint32_t        flags;
        uint32_t        unused;
};

struct fuse_create_in {
        uint32_t        flags;
        uint32_t        mode;
        uint32_t        umask;
        uint32_t        padding;
};

struct fuse_open_out {
        uint64_t        fh;
        uint32_t        open_flags;
        uint32_t        padding;
};

struct fuse_release_in {
        uint64_t        fh;
        uint32_t        flags;
        uint32_t        release_flags;
        uint64_t        lock_owner;
};

struct fuse_flush_in {
        uint64_t        fh;
        uint32_t        unused;
        uint32_t        padding;
        uint64_t        lock_owner;
};

struct fuse_read_in {
        uint64_t        fh;
        uint64_t        offset;
        uint32_t        size;
        uint32_t        read_flags;
        uint64_t        lock_owner;
        uint32_t        flags;
        uint32_t        padding;
};

#define FUSE_COMPAT_WRITE_IN_SIZE 24

struct fuse_write_in {
        uint64_t        fh;
        uint64_t        offset;
        uint32_t        size;
        uint32_t        write_flags;
        uint64_t        lock_owner;
        uint32_t        flags;
        uint32_t        padding;
};

struct fuse_write_out {
        uint32_t        size;
        uint32_t        padding;
};

#define FUSE_COMPAT_STATFS_SIZE 48

struct fuse_statfs_out {
        struct fuse_kstatfs st;
};

struct fuse_fsync_in {
        uint64_t        fh;
        uint32_t        fsync_flags;
        uint32_t        padding;
};

struct fuse_setxattr_in {
        uint32_t        size;
        uint32_t        flags;
};

struct fuse_getxattr_in {
        uint32_t        size;
        uint32_t        padding;
};

struct fuse_getxattr_out {
        uint32_t        size;
        uint32_t        padding;
};

struct fuse_lk_in {
        uint64_t        fh;
        uint64_t        owner;
        struct fuse_file_lock lk;
        uint32_t        lk_flags;
        uint32_t        padding;
};

struct fuse_lk_out {
        struct fuse_file_lock lk;
};

struct fuse_access_in {
        uint32_t        mask;
        uint32_t        padding;
};

struct fuse_init_in {
        uint32_t        major;
        uint32_t        minor;
        uint32_t        max_readahead;
        uint32_t        flags;
};

#define FUSE_COMPAT_INIT_OUT_SIZE 8
#define FUSE_COMPAT_22_INIT_OUT_SIZE 24

struct fuse_init_out {
        uint32_t        major;
        uint32_t        minor;
        uint32_t        max_readahead;
        uint32_t        flags;
        uint16_t        max_background;
        uint16_t        congestion_threshold;
        uint32_t        max_write;
        uint32_t        time_gran;
        uint32_t        unused[9];
};

#define CUSE_INIT_INFO_MAX 4096

struct cuse_init_in {
        uint32_t        major;
        uint32_t        minor;
        uint32_t        unused;
        uint32_t        flags;
};

struct cuse_init_out {
        uint32_t        major;
        uint32_t        minor;
        uint32_t        unused;
        uint32_t        flags;
        uint32_t        max_read;
        uint32_t        max_write;
        uint32_t        dev_major;              /* chardev major */
        uint32_t        dev_minor;              /* chardev minor */
        uint32_t        spare[10];
};

struct fuse_interrupt_in {
        uint64_t        unique;
};

struct fuse_bmap_in {
        uint64_t        block;
        uint32_t        blocksize;
        uint32_t        padding;
};

struct fuse_bmap_out {
        uint64_t        block;
};

struct fuse_ioctl_in {
        uint64_t        fh;
        uint32_t        flags;
        uint32_t        cmd;
        uint64_t        arg;
        uint32_t        in_size;
        uint32_t        out_size;
};

struct fuse_ioctl_iovec {
        uint64_t        base;
        uint64_t        len;
};

struct fuse_ioctl_out {
        int32_t         result;
        uint32_t        flags;
        uint32_t        in_iovs;
        uint32_t        out_iovs;
};

struct fuse_poll_in {
        uint64_t        fh;
        uint64_t        kh;
        uint32_t        flags;
        uint32_t        events;
};

struct fuse_poll_out {
        uint32_t        revents;
        uint32_t        padding;
};

struct fuse_notify_poll_wakeup_out {
        uint64_t        kh;
};

struct fuse_fallocate_in {
        uint64_t        fh;
        uint64_t        offset;
        uint64_t        length;
        uint32_t        mode;
        uint32_t        padding;
};

struct fuse_in_header {
        uint32_t        len;
        uint32_t        opcode;
        uint64_t        unique;
        uint64_t        nodeid;
        uint32_t        uid;
        uint32_t        gid;
        uint32_t        pid;
        uint32_t        padding;
};

struct fuse_out_header {
        uint32_t        len;
        int32_t         error;
        uint64_t        unique;
};

struct fuse_dirent {
        uint64_t        ino;
        uint64_t        off;
        uint32_t        namelen;
        uint32_t        type;
        char name[];
};

#define FUSE_NAME_OFFSET offsetof(struct fuse_dirent, name)
#define FUSE_DIRENT_ALIGN(x) \
        (((x) + sizeof(uint64_t) - 1) & ~(sizeof(uint64_t) - 1))
#define FUSE_DIRENT_SIZE(d) \
        FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + (d)->namelen)

struct fuse_direntplus {
        struct fuse_entry_out entry_out;
        struct fuse_dirent dirent;
};

#define FUSE_NAME_OFFSET_DIRENTPLUS \
        offsetof(struct fuse_direntplus, dirent.name)
#define FUSE_DIRENTPLUS_SIZE(d) \
        FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET_DIRENTPLUS + (d)->dirent.namelen)

struct fuse_notify_inval_inode_out {
        uint64_t        ino;
        int64_t         off;
        int64_t         len;
};

struct fuse_notify_inval_entry_out {
        uint64_t        parent;
        uint32_t        namelen;
        uint32_t        padding;
};

struct fuse_notify_delete_out {
        uint64_t        parent;
        uint64_t        child;
        uint32_t        namelen;
        uint32_t        padding;
};

struct fuse_notify_store_out {
        uint64_t        nodeid;
        uint64_t        offset;
        uint32_t        size;
        uint32_t        padding;
};

struct fuse_notify_retrieve_out {
        uint64_t        notify_unique;
        uint64_t        nodeid;
        uint64_t        offset;
        uint32_t        size;
        uint32_t        padding;
};

/* Matches the size of fuse_write_in */
struct fuse_notify_retrieve_in {
        uint64_t        dummy1;
        uint64_t        offset;
        uint32_t        size;
        uint32_t        dummy2;
        uint64_t        dummy3;
        uint64_t        dummy4;
};

/* Device ioctls: */
#define FUSE_DEV_IOC_CLONE      _IOR(229, 0, uint32_t)

struct fuse_lseek_in {
        uint64_t        fh;
        uint64_t        offset;
        uint32_t        whence;
        uint32_t        padding;
};

struct fuse_lseek_out {
        uint64_t        offset;
};

struct fuse_copy_file_range_in {
        uint64_t        fh_in;
        uint64_t        off_in;
        uint64_t        nodeid_out;
        uint64_t        fh_out;
        uint64_t        off_out;
        uint64_t        len;
        uint64_t        flags;
};

#endif /* _LINUX_FUSE_H */