Proxmox-Port/linux-loongson
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson synced 2025-10-31 03:13:59 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
d01d0756f7
linux-loongson/include/linux/fuse.h
Miklos Szeredi dd3bb14f44 fuse: support splice() writing to fuse device 
Allow userspace filesystem implementation to use splice() to write to
the fuse device.  The semantics of using splice() are:

 1) buffer the message header and data in a temporary pipe
 2) with a *single* splice() call move the message from the temporary pipe
    to the fuse device

The READ reply message has the most interesting use for this, since
now the data from an arbitrary file descriptor (which could be a
regular file, a block device or a socket) can be tranferred into the
fuse device without having to go through a userspace buffer.  It will
also allow zero copy moving of pages.

One caveat is that the protocol on the fuse device requires the length
of the whole message to be written into the header.  But the length of
the data transferred into the temporary pipe may not be known in
advance.  The current library implementation works around this by
using vmplice to write the header and modifying the header after
splicing the data into the pipe (error handling omitted):

	struct fuse_out_header out;

	iov.iov_base = &out;
	iov.iov_len = sizeof(struct fuse_out_header);
	vmsplice(pip[1], &iov, 1, 0);
	len = splice(input_fd, input_offset, pip[1], NULL, len, 0);
	/* retrospectively modify the header: */
	out.len = len + sizeof(struct fuse_out_header);
	splice(pip[0], NULL, fuse_chan_fd(req->ch), NULL, out.len, flags);

This works since vmsplice only saves a pointer to the data, it does
not copy the data itself.

Since pipes are currently limited to 16 pages and messages need to be
spliced atomically, the length of the data is limited to 15 pages (or
60kB for 4k pages).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-05-25 15:06:06 +02:00

572 lines
10 KiB
C
Raw Blame History

/*
FUSE: Filesystem in Userspace
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 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
*/
#ifndef _LINUX_FUSE_H
#define _LINUX_FUSE_H
#include <linux/types.h>
/*
* 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).
*/
/** Version number of this interface */
#define FUSE_KERNEL_VERSION 7
/** Minor version number of this interface */
#define FUSE_KERNEL_MINOR_VERSION 14
/** The node ID of the root inode */
#define FUSE_ROOT_ID 1
/* Make sure all structures are padded to 64bit boundary, so 32bit
userspace works under 64bit kernels */
struct fuse_attr {
__u64 ino;
__u64 size;
__u64 blocks;
__u64 atime;
__u64 mtime;
__u64 ctime;
__u32 atimensec;
__u32 mtimensec;
__u32 ctimensec;
__u32 mode;
__u32 nlink;
__u32 uid;
__u32 gid;
__u32 rdev;
__u32 blksize;
__u32 padding;
};
struct fuse_kstatfs {
__u64 blocks;
__u64 bfree;
__u64 bavail;
__u64 files;
__u64 ffree;
__u32 bsize;
__u32 namelen;
__u32 frsize;
__u32 padding;
__u32 spare[6];
};
struct fuse_file_lock {
__u64 start;
__u64 end;
__u32 type;
__u32 pid; /* tgid */
};
/**
* Bitmasks for fuse_setattr_in.valid
*/
#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)
/**
* Flags returned by the OPEN request
*
* FOPEN_DIRECT_IO: bypass page cache for this open file
* FOPEN_KEEP_CACHE: don't invalidate the data cache on open
* FOPEN_NONSEEKABLE: the file is not seekable
*/
#define FOPEN_DIRECT_IO (1 << 0)
#define FOPEN_KEEP_CACHE (1 << 1)
#define FOPEN_NONSEEKABLE (1 << 2)
/**
* INIT request/reply flags
*
* FUSE_EXPORT_SUPPORT: filesystem handles lookups of "." and ".."
* FUSE_DONT_MASK: don't apply umask to file mode on create operations
*/
#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)
/**
* CUSE INIT request/reply flags
*
* CUSE_UNRESTRICTED_IOCTL: use unrestricted ioctl
*/
#define CUSE_UNRESTRICTED_IOCTL (1 << 0)
/**
* Release flags
*/
#define FUSE_RELEASE_FLUSH (1 << 0)
/**
* Getattr flags
*/
#define FUSE_GETATTR_FH (1 << 0)
/**
* Lock flags
*/
#define FUSE_LK_FLOCK (1 << 0)
/**
* WRITE flags
*
* FUSE_WRITE_CACHE: delayed write from page cache, file handle is guessed
* FUSE_WRITE_LOCKOWNER: lock_owner field is valid
*/
#define FUSE_WRITE_CACHE (1 << 0)
#define FUSE_WRITE_LOCKOWNER (1 << 1)
/**
* Read flags
*/
#define FUSE_READ_LOCKOWNER (1 << 1)
/**
* Ioctl flags
*
* FUSE_IOCTL_COMPAT: 32bit compat ioctl on 64bit machine
* FUSE_IOCTL_UNRESTRICTED: not restricted to well-formed ioctls, retry allowed
* FUSE_IOCTL_RETRY: retry with new iovecs
*
* FUSE_IOCTL_MAX_IOV: maximum of in_iovecs + out_iovecs
*/
#define FUSE_IOCTL_COMPAT (1 << 0)
#define FUSE_IOCTL_UNRESTRICTED (1 << 1)
#define FUSE_IOCTL_RETRY (1 << 2)
#define FUSE_IOCTL_MAX_IOV 256
/**
* Poll flags
*
* FUSE_POLL_SCHEDULE_NOTIFY: request poll notify
*/
#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,
/* 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_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 {
__u64 nodeid; /* Inode ID */
__u64 generation; /* Inode generation: nodeid:gen must
be unique for the fs's lifetime */
__u64 entry_valid; /* Cache timeout for the name */
__u64 attr_valid; /* Cache timeout for the attributes */
__u32 entry_valid_nsec;
__u32 attr_valid_nsec;
struct fuse_attr attr;
};
struct fuse_forget_in {
__u64 nlookup;
};
struct fuse_getattr_in {
__u32 getattr_flags;
__u32 dummy;
__u64 fh;
};
#define FUSE_COMPAT_ATTR_OUT_SIZE 96
struct fuse_attr_out {
__u64 attr_valid; /* Cache timeout for the attributes */
__u32 attr_valid_nsec;
__u32 dummy;
struct fuse_attr attr;
};
#define FUSE_COMPAT_MKNOD_IN_SIZE 8
struct fuse_mknod_in {
__u32 mode;
__u32 rdev;
__u32 umask;
__u32 padding;
};
struct fuse_mkdir_in {
__u32 mode;
__u32 umask;
};
struct fuse_rename_in {
__u64 newdir;
};
struct fuse_link_in {
__u64 oldnodeid;
};
struct fuse_setattr_in {
__u32 valid;
__u32 padding;
__u64 fh;
__u64 size;
__u64 lock_owner;
__u64 atime;
__u64 mtime;
__u64 unused2;
__u32 atimensec;
__u32 mtimensec;
__u32 unused3;
__u32 mode;
__u32 unused4;
__u32 uid;
__u32 gid;
__u32 unused5;
};
struct fuse_open_in {
__u32 flags;
__u32 unused;
};
struct fuse_create_in {
__u32 flags;
__u32 mode;
__u32 umask;
__u32 padding;
};
struct fuse_open_out {
__u64 fh;
__u32 open_flags;
__u32 padding;
};
struct fuse_release_in {
__u64 fh;
__u32 flags;
__u32 release_flags;
__u64 lock_owner;
};
struct fuse_flush_in {
__u64 fh;
__u32 unused;
__u32 padding;
__u64 lock_owner;
};
struct fuse_read_in {
__u64 fh;
__u64 offset;
__u32 size;
__u32 read_flags;
__u64 lock_owner;
__u32 flags;
__u32 padding;
};
#define FUSE_COMPAT_WRITE_IN_SIZE 24
struct fuse_write_in {
__u64 fh;
__u64 offset;
__u32 size;
__u32 write_flags;
__u64 lock_owner;
__u32 flags;
__u32 padding;
};
struct fuse_write_out {
__u32 size;
__u32 padding;
};
#define FUSE_COMPAT_STATFS_SIZE 48
struct fuse_statfs_out {
struct fuse_kstatfs st;
};
struct fuse_fsync_in {
__u64 fh;
__u32 fsync_flags;
__u32 padding;
};
struct fuse_setxattr_in {
__u32 size;
__u32 flags;
};
struct fuse_getxattr_in {
__u32 size;
__u32 padding;
};
struct fuse_getxattr_out {
__u32 size;
__u32 padding;
};
struct fuse_lk_in {
__u64 fh;
__u64 owner;
struct fuse_file_lock lk;
__u32 lk_flags;
__u32 padding;
};
struct fuse_lk_out {
struct fuse_file_lock lk;
};
struct fuse_access_in {
__u32 mask;
__u32 padding;
};
struct fuse_init_in {
__u32 major;
__u32 minor;
__u32 max_readahead;
__u32 flags;
};
struct fuse_init_out {
__u32 major;
__u32 minor;
__u32 max_readahead;
__u32 flags;
__u16 max_background;
__u16 congestion_threshold;
__u32 max_write;
};
#define CUSE_INIT_INFO_MAX 4096
struct cuse_init_in {
__u32 major;
__u32 minor;
__u32 unused;
__u32 flags;
};
struct cuse_init_out {
__u32 major;
__u32 minor;
__u32 unused;
__u32 flags;
__u32 max_read;
__u32 max_write;
__u32 dev_major; /* chardev major */
__u32 dev_minor; /* chardev minor */
__u32 spare[10];
};
struct fuse_interrupt_in {
__u64 unique;
};
struct fuse_bmap_in {
__u64 block;
__u32 blocksize;
__u32 padding;
};
struct fuse_bmap_out {
__u64 block;
};
struct fuse_ioctl_in {
__u64 fh;
__u32 flags;
__u32 cmd;
__u64 arg;
__u32 in_size;
__u32 out_size;
};
struct fuse_ioctl_out {
__s32 result;
__u32 flags;
__u32 in_iovs;
__u32 out_iovs;
};
struct fuse_poll_in {
__u64 fh;
__u64 kh;
__u32 flags;
__u32 padding;
};
struct fuse_poll_out {
__u32 revents;
__u32 padding;
};
struct fuse_notify_poll_wakeup_out {
__u64 kh;
};
struct fuse_in_header {
__u32 len;
__u32 opcode;
__u64 unique;
__u64 nodeid;
__u32 uid;
__u32 gid;
__u32 pid;
__u32 padding;
};
struct fuse_out_header {
__u32 len;
__s32 error;
__u64 unique;
};
struct fuse_dirent {
__u64 ino;
__u64 off;
__u32 namelen;
__u32 type;
char name[0];
};
#define FUSE_NAME_OFFSET offsetof(struct fuse_dirent, name)
#define FUSE_DIRENT_ALIGN(x) (((x) + sizeof(__u64) - 1) & ~(sizeof(__u64) - 1))
#define FUSE_DIRENT_SIZE(d) \
FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + (d)->namelen)
struct fuse_notify_inval_inode_out {
__u64 ino;
__s64 off;
__s64 len;
};
struct fuse_notify_inval_entry_out {
__u64 parent;
__u32 namelen;
__u32 padding;
};
#endif /* _LINUX_FUSE_H */
Reference in New Issue View Git Blame Copy Permalink