From: "Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>
To: qemu-devel@nongnu.org, stefanha@redhat.com, vgoyal@redhat.com
Subject: [PATCH 001/104] virtiofsd: Pull in upstream headers
Date: Thu, 12 Dec 2019 16:37:21 +0000 [thread overview]
Message-ID: <20191212163904.159893-2-dgilbert@redhat.com> (raw)
In-Reply-To: <20191212163904.159893-1-dgilbert@redhat.com>
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Pull in headers fromlibfuse's upstream fuse-3.8.0
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
tools/virtiofsd/fuse.h | 1275 +++++++++++++++
tools/virtiofsd/fuse_common.h | 823 ++++++++++
tools/virtiofsd/fuse_i.h | 139 ++
tools/virtiofsd/fuse_log.h | 82 +
tools/virtiofsd/fuse_lowlevel.h | 2089 +++++++++++++++++++++++++
tools/virtiofsd/fuse_misc.h | 59 +
tools/virtiofsd/fuse_opt.h | 271 ++++
tools/virtiofsd/passthrough_helpers.h | 76 +
8 files changed, 4814 insertions(+)
create mode 100644 tools/virtiofsd/fuse.h
create mode 100644 tools/virtiofsd/fuse_common.h
create mode 100644 tools/virtiofsd/fuse_i.h
create mode 100644 tools/virtiofsd/fuse_log.h
create mode 100644 tools/virtiofsd/fuse_lowlevel.h
create mode 100644 tools/virtiofsd/fuse_misc.h
create mode 100644 tools/virtiofsd/fuse_opt.h
create mode 100644 tools/virtiofsd/passthrough_helpers.h
diff --git a/tools/virtiofsd/fuse.h b/tools/virtiofsd/fuse.h
new file mode 100644
index 0000000000..883f6e59fb
--- /dev/null
+++ b/tools/virtiofsd/fuse.h
@@ -0,0 +1,1275 @@
+/*
+ FUSE: Filesystem in Userspace
+ Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
+
+ This program can be distributed under the terms of the GNU LGPLv2.
+ See the file COPYING.LIB.
+*/
+
+#ifndef FUSE_H_
+#define FUSE_H_
+
+/** @file
+ *
+ * This file defines the library interface of FUSE
+ *
+ * IMPORTANT: you should define FUSE_USE_VERSION before including this header.
+ */
+
+#include "fuse_common.h"
+
+#include <fcntl.h>
+#include <time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include <sys/uio.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* ----------------------------------------------------------- *
+ * Basic FUSE API *
+ * ----------------------------------------------------------- */
+
+/** Handle for a FUSE filesystem */
+struct fuse;
+
+/**
+ * Readdir flags, passed to ->readdir()
+ */
+enum fuse_readdir_flags {
+ /**
+ * "Plus" mode.
+ *
+ * The kernel wants to prefill the inode cache during readdir. The
+ * filesystem may honour this by filling in the attributes and setting
+ * FUSE_FILL_DIR_FLAGS for the filler function. The filesystem may also
+ * just ignore this flag completely.
+ */
+ FUSE_READDIR_PLUS = (1 << 0),
+};
+
+enum fuse_fill_dir_flags {
+ /**
+ * "Plus" mode: all file attributes are valid
+ *
+ * The attributes are used by the kernel to prefill the inode cache
+ * during a readdir.
+ *
+ * It is okay to set FUSE_FILL_DIR_PLUS if FUSE_READDIR_PLUS is not set
+ * and vice versa.
+ */
+ FUSE_FILL_DIR_PLUS = (1 << 1),
+};
+
+/** Function to add an entry in a readdir() operation
+ *
+ * The *off* parameter can be any non-zero value that enables the
+ * filesystem to identify the current point in the directory
+ * stream. It does not need to be the actual physical position. A
+ * value of zero is reserved to indicate that seeking in directories
+ * is not supported.
+ *
+ * @param buf the buffer passed to the readdir() operation
+ * @param name the file name of the directory entry
+ * @param stat file attributes, can be NULL
+ * @param off offset of the next entry or zero
+ * @param flags fill flags
+ * @return 1 if buffer is full, zero otherwise
+ */
+typedef int (*fuse_fill_dir_t) (void *buf, const char *name,
+ const struct stat *stbuf, off_t off,
+ enum fuse_fill_dir_flags flags);
+/**
+ * Configuration of the high-level API
+ *
+ * This structure is initialized from the arguments passed to
+ * fuse_new(), and then passed to the file system's init() handler
+ * which should ensure that the configuration is compatible with the
+ * file system implementation.
+ */
+struct fuse_config {
+ /**
+ * If `set_gid` is non-zero, the st_gid attribute of each file
+ * is overwritten with the value of `gid`.
+ */
+ int set_gid;
+ unsigned int gid;
+
+ /**
+ * If `set_uid` is non-zero, the st_uid attribute of each file
+ * is overwritten with the value of `uid`.
+ */
+ int set_uid;
+ unsigned int uid;
+
+ /**
+ * If `set_mode` is non-zero, the any permissions bits set in
+ * `umask` are unset in the st_mode attribute of each file.
+ */
+ int set_mode;
+ unsigned int umask;
+
+ /**
+ * The timeout in seconds for which name lookups will be
+ * cached.
+ */
+ double entry_timeout;
+
+ /**
+ * The timeout in seconds for which a negative lookup will be
+ * cached. This means, that if file did not exist (lookup
+ * retuned ENOENT), the lookup will only be redone after the
+ * timeout, and the file/directory will be assumed to not
+ * exist until then. A value of zero means that negative
+ * lookups are not cached.
+ */
+ double negative_timeout;
+
+ /**
+ * The timeout in seconds for which file/directory attributes
+ * (as returned by e.g. the `getattr` handler) are cached.
+ */
+ double attr_timeout;
+
+ /**
+ * Allow requests to be interrupted
+ */
+ int intr;
+
+ /**
+ * Specify which signal number to send to the filesystem when
+ * a request is interrupted. The default is hardcoded to
+ * USR1.
+ */
+ int intr_signal;
+
+ /**
+ * Normally, FUSE assigns inodes to paths only for as long as
+ * the kernel is aware of them. With this option inodes are
+ * instead remembered for at least this many seconds. This
+ * will require more memory, but may be necessary when using
+ * applications that make use of inode numbers.
+ *
+ * A number of -1 means that inodes will be remembered for the
+ * entire life-time of the file-system process.
+ */
+ int remember;
+
+ /**
+ * The default behavior is that if an open file is deleted,
+ * the file is renamed to a hidden file (.fuse_hiddenXXX), and
+ * only removed when the file is finally released. This
+ * relieves the filesystem implementation of having to deal
+ * with this problem. This option disables the hiding
+ * behavior, and files are removed immediately in an unlink
+ * operation (or in a rename operation which overwrites an
+ * existing file).
+ *
+ * It is recommended that you not use the hard_remove
+ * option. When hard_remove is set, the following libc
+ * functions fail on unlinked files (returning errno of
+ * ENOENT): read(2), write(2), fsync(2), close(2), f*xattr(2),
+ * ftruncate(2), fstat(2), fchmod(2), fchown(2)
+ */
+ int hard_remove;
+
+ /**
+ * Honor the st_ino field in the functions getattr() and
+ * fill_dir(). This value is used to fill in the st_ino field
+ * in the stat(2), lstat(2), fstat(2) functions and the d_ino
+ * field in the readdir(2) function. The filesystem does not
+ * have to guarantee uniqueness, however some applications
+ * rely on this value being unique for the whole filesystem.
+ *
+ * Note that this does *not* affect the inode that libfuse
+ * and the kernel use internally (also called the "nodeid").
+ */
+ int use_ino;
+
+ /**
+ * If use_ino option is not given, still try to fill in the
+ * d_ino field in readdir(2). If the name was previously
+ * looked up, and is still in the cache, the inode number
+ * found there will be used. Otherwise it will be set to -1.
+ * If use_ino option is given, this option is ignored.
+ */
+ int readdir_ino;
+
+ /**
+ * This option disables the use of page cache (file content cache)
+ * in the kernel for this filesystem. This has several affects:
+ *
+ * 1. Each read(2) or write(2) system call will initiate one
+ * or more read or write operations, data will not be
+ * cached in the kernel.
+ *
+ * 2. The return value of the read() and write() system calls
+ * will correspond to the return values of the read and
+ * write operations. This is useful for example if the
+ * file size is not known in advance (before reading it).
+ *
+ * Internally, enabling this option causes fuse to set the
+ * `direct_io` field of `struct fuse_file_info` - overwriting
+ * any value that was put there by the file system.
+ */
+ int direct_io;
+
+ /**
+ * This option disables flushing the cache of the file
+ * contents on every open(2). This should only be enabled on
+ * filesystems where the file data is never changed
+ * externally (not through the mounted FUSE filesystem). Thus
+ * it is not suitable for network filesystems and other
+ * intermediate filesystems.
+ *
+ * NOTE: if this option is not specified (and neither
+ * direct_io) data is still cached after the open(2), so a
+ * read(2) system call will not always initiate a read
+ * operation.
+ *
+ * Internally, enabling this option causes fuse to set the
+ * `keep_cache` field of `struct fuse_file_info` - overwriting
+ * any value that was put there by the file system.
+ */
+ int kernel_cache;
+
+ /**
+ * This option is an alternative to `kernel_cache`. Instead of
+ * unconditionally keeping cached data, the cached data is
+ * invalidated on open(2) if if the modification time or the
+ * size of the file has changed since it was last opened.
+ */
+ int auto_cache;
+
+ /**
+ * The timeout in seconds for which file attributes are cached
+ * for the purpose of checking if auto_cache should flush the
+ * file data on open.
+ */
+ int ac_attr_timeout_set;
+ double ac_attr_timeout;
+
+ /**
+ * If this option is given the file-system handlers for the
+ * following operations will not receive path information:
+ * read, write, flush, release, fsync, readdir, releasedir,
+ * fsyncdir, lock, ioctl and poll.
+ *
+ * For the truncate, getattr, chmod, chown and utimens
+ * operations the path will be provided only if the struct
+ * fuse_file_info argument is NULL.
+ */
+ int nullpath_ok;
+
+ /**
+ * The remaining options are used by libfuse internally and
+ * should not be touched.
+ */
+ int show_help;
+ char *modules;
+ int debug;
+};
+
+
+/**
+ * The file system operations:
+ *
+ * Most of these should work very similarly to the well known UNIX
+ * file system operations. A major exception is that instead of
+ * returning an error in 'errno', the operation should return the
+ * negated error value (-errno) directly.
+ *
+ * All methods are optional, but some are essential for a useful
+ * filesystem (e.g. getattr). Open, flush, release, fsync, opendir,
+ * releasedir, fsyncdir, access, create, truncate, lock, init and
+ * destroy are special purpose methods, without which a full featured
+ * filesystem can still be implemented.
+ *
+ * In general, all methods are expected to perform any necessary
+ * permission checking. However, a filesystem may delegate this task
+ * to the kernel by passing the `default_permissions` mount option to
+ * `fuse_new()`. In this case, methods will only be called if
+ * the kernel's permission check has succeeded.
+ *
+ * Almost all operations take a path which can be of any length.
+ */
+struct fuse_operations {
+ /** Get file attributes.
+ *
+ * Similar to stat(). The 'st_dev' and 'st_blksize' fields are
+ * ignored. The 'st_ino' field is ignored except if the 'use_ino'
+ * mount option is given. In that case it is passed to userspace,
+ * but libfuse and the kernel will still assign a different
+ * inode for internal use (called the "nodeid").
+ *
+ * `fi` will always be NULL if the file is not currently open, but
+ * may also be NULL if the file is open.
+ */
+ int (*getattr) (const char *, struct stat *, struct fuse_file_info *fi);
+
+ /** Read the target of a symbolic link
+ *
+ * The buffer should be filled with a null terminated string. The
+ * buffer size argument includes the space for the terminating
+ * null character. If the linkname is too long to fit in the
+ * buffer, it should be truncated. The return value should be 0
+ * for success.
+ */
+ int (*readlink) (const char *, char *, size_t);
+
+ /** Create a file node
+ *
+ * This is called for creation of all non-directory, non-symlink
+ * nodes. If the filesystem defines a create() method, then for
+ * regular files that will be called instead.
+ */
+ int (*mknod) (const char *, mode_t, dev_t);
+
+ /** Create a directory
+ *
+ * Note that the mode argument may not have the type specification
+ * bits set, i.e. S_ISDIR(mode) can be false. To obtain the
+ * correct directory type bits use mode|S_IFDIR
+ * */
+ int (*mkdir) (const char *, mode_t);
+
+ /** Remove a file */
+ int (*unlink) (const char *);
+
+ /** Remove a directory */
+ int (*rmdir) (const char *);
+
+ /** Create a symbolic link */
+ int (*symlink) (const char *, const char *);
+
+ /** Rename a file
+ *
+ * *flags* may be `RENAME_EXCHANGE` or `RENAME_NOREPLACE`. If
+ * RENAME_NOREPLACE is specified, the filesystem must not
+ * overwrite *newname* if it exists and return an error
+ * instead. If `RENAME_EXCHANGE` is specified, the filesystem
+ * must atomically exchange the two files, i.e. both must
+ * exist and neither may be deleted.
+ */
+ int (*rename) (const char *, const char *, unsigned int flags);
+
+ /** Create a hard link to a file */
+ int (*link) (const char *, const char *);
+
+ /** Change the permission bits of a file
+ *
+ * `fi` will always be NULL if the file is not currenlty open, but
+ * may also be NULL if the file is open.
+ */
+ int (*chmod) (const char *, mode_t, struct fuse_file_info *fi);
+
+ /** Change the owner and group of a file
+ *
+ * `fi` will always be NULL if the file is not currenlty open, but
+ * may also be NULL if the file is open.
+ *
+ * Unless FUSE_CAP_HANDLE_KILLPRIV is disabled, this method is
+ * expected to reset the setuid and setgid bits.
+ */
+ int (*chown) (const char *, uid_t, gid_t, struct fuse_file_info *fi);
+
+ /** Change the size of a file
+ *
+ * `fi` will always be NULL if the file is not currenlty open, but
+ * may also be NULL if the file is open.
+ *
+ * Unless FUSE_CAP_HANDLE_KILLPRIV is disabled, this method is
+ * expected to reset the setuid and setgid bits.
+ */
+ int (*truncate) (const char *, off_t, struct fuse_file_info *fi);
+
+ /** Open a file
+ *
+ * Open flags are available in fi->flags. The following rules
+ * apply.
+ *
+ * - Creation (O_CREAT, O_EXCL, O_NOCTTY) flags will be
+ * filtered out / handled by the kernel.
+ *
+ * - Access modes (O_RDONLY, O_WRONLY, O_RDWR, O_EXEC, O_SEARCH)
+ * should be used by the filesystem to check if the operation is
+ * permitted. If the ``-o default_permissions`` mount option is
+ * given, this check is already done by the kernel before calling
+ * open() and may thus be omitted by the filesystem.
+ *
+ * - When writeback caching is enabled, the kernel may send
+ * read requests even for files opened with O_WRONLY. The
+ * filesystem should be prepared to handle this.
+ *
+ * - When writeback caching is disabled, the filesystem is
+ * expected to properly handle the O_APPEND flag and ensure
+ * that each write is appending to the end of the file.
+ *
+ * - When writeback caching is enabled, the kernel will
+ * handle O_APPEND. However, unless all changes to the file
+ * come through the kernel this will not work reliably. The
+ * filesystem should thus either ignore the O_APPEND flag
+ * (and let the kernel handle it), or return an error
+ * (indicating that reliably O_APPEND is not available).
+ *
+ * Filesystem may store an arbitrary file handle (pointer,
+ * index, etc) in fi->fh, and use this in other all other file
+ * operations (read, write, flush, release, fsync).
+ *
+ * Filesystem may also implement stateless file I/O and not store
+ * anything in fi->fh.
+ *
+ * There are also some flags (direct_io, keep_cache) which the
+ * filesystem may set in fi, to change the way the file is opened.
+ * See fuse_file_info structure in <fuse_common.h> for more details.
+ *
+ * If this request is answered with an error code of ENOSYS
+ * and FUSE_CAP_NO_OPEN_SUPPORT is set in
+ * `fuse_conn_info.capable`, this is treated as success and
+ * future calls to open will also succeed without being send
+ * to the filesystem process.
+ *
+ */
+ int (*open) (const char *, struct fuse_file_info *);
+
+ /** Read data from an open file
+ *
+ * Read should return exactly the number of bytes requested except
+ * on EOF or error, otherwise the rest of the data will be
+ * substituted with zeroes. An exception to this is when the
+ * 'direct_io' mount option is specified, in which case the return
+ * value of the read system call will reflect the return value of
+ * this operation.
+ */
+ int (*read) (const char *, char *, size_t, off_t,
+ struct fuse_file_info *);
+
+ /** Write data to an open file
+ *
+ * Write should return exactly the number of bytes requested
+ * except on error. An exception to this is when the 'direct_io'
+ * mount option is specified (see read operation).
+ *
+ * Unless FUSE_CAP_HANDLE_KILLPRIV is disabled, this method is
+ * expected to reset the setuid and setgid bits.
+ */
+ int (*write) (const char *, const char *, size_t, off_t,
+ struct fuse_file_info *);
+
+ /** Get file system statistics
+ *
+ * The 'f_favail', 'f_fsid' and 'f_flag' fields are ignored
+ */
+ int (*statfs) (const char *, struct statvfs *);
+
+ /** Possibly flush cached data
+ *
+ * BIG NOTE: This is not equivalent to fsync(). It's not a
+ * request to sync dirty data.
+ *
+ * Flush is called on each close() of a file descriptor, as opposed to
+ * release which is called on the close of the last file descriptor for
+ * a file. Under Linux, errors returned by flush() will be passed to
+ * userspace as errors from close(), so flush() is a good place to write
+ * back any cached dirty data. However, many applications ignore errors
+ * on close(), and on non-Linux systems, close() may succeed even if flush()
+ * returns an error. For these reasons, filesystems should not assume
+ * that errors returned by flush will ever be noticed or even
+ * delivered.
+ *
+ * NOTE: The flush() method may be called more than once for each
+ * open(). This happens if more than one file descriptor refers to an
+ * open file handle, e.g. due to dup(), dup2() or fork() calls. It is
+ * not possible to determine if a flush is final, so each flush should
+ * be treated equally. Multiple write-flush sequences are relatively
+ * rare, so this shouldn't be a problem.
+ *
+ * Filesystems shouldn't assume that flush will be called at any
+ * particular point. It may be called more times than expected, or not
+ * at all.
+ *
+ * [close]: http://pubs.opengroup.org/onlinepubs/9699919799/functions/close.html
+ */
+ int (*flush) (const char *, struct fuse_file_info *);
+
+ /** Release an open file
+ *
+ * Release is called when there are no more references to an open
+ * file: all file descriptors are closed and all memory mappings
+ * are unmapped.
+ *
+ * For every open() call there will be exactly one release() call
+ * with the same flags and file handle. It is possible to
+ * have a file opened more than once, in which case only the last
+ * release will mean, that no more reads/writes will happen on the
+ * file. The return value of release is ignored.
+ */
+ int (*release) (const char *, struct fuse_file_info *);
+
+ /** Synchronize file contents
+ *
+ * If the datasync parameter is non-zero, then only the user data
+ * should be flushed, not the meta data.
+ */
+ int (*fsync) (const char *, int, struct fuse_file_info *);
+
+ /** Set extended attributes */
+ int (*setxattr) (const char *, const char *, const char *, size_t, int);
+
+ /** Get extended attributes */
+ int (*getxattr) (const char *, const char *, char *, size_t);
+
+ /** List extended attributes */
+ int (*listxattr) (const char *, char *, size_t);
+
+ /** Remove extended attributes */
+ int (*removexattr) (const char *, const char *);
+
+ /** Open directory
+ *
+ * Unless the 'default_permissions' mount option is given,
+ * this method should check if opendir is permitted for this
+ * directory. Optionally opendir may also return an arbitrary
+ * filehandle in the fuse_file_info structure, which will be
+ * passed to readdir, releasedir and fsyncdir.
+ */
+ int (*opendir) (const char *, struct fuse_file_info *);
+
+ /** Read directory
+ *
+ * The filesystem may choose between two modes of operation:
+ *
+ * 1) The readdir implementation ignores the offset parameter, and
+ * passes zero to the filler function's offset. The filler
+ * function will not return '1' (unless an error happens), so the
+ * whole directory is read in a single readdir operation.
+ *
+ * 2) The readdir implementation keeps track of the offsets of the
+ * directory entries. It uses the offset parameter and always
+ * passes non-zero offset to the filler function. When the buffer
+ * is full (or an error happens) the filler function will return
+ * '1'.
+ */
+ int (*readdir) (const char *, void *, fuse_fill_dir_t, off_t,
+ struct fuse_file_info *, enum fuse_readdir_flags);
+
+ /** Release directory
+ */
+ int (*releasedir) (const char *, struct fuse_file_info *);
+
+ /** Synchronize directory contents
+ *
+ * If the datasync parameter is non-zero, then only the user data
+ * should be flushed, not the meta data
+ */
+ int (*fsyncdir) (const char *, int, struct fuse_file_info *);
+
+ /**
+ * Initialize filesystem
+ *
+ * The return value will passed in the `private_data` field of
+ * `struct fuse_context` to all file operations, and as a
+ * parameter to the destroy() method. It overrides the initial
+ * value provided to fuse_main() / fuse_new().
+ */
+ void *(*init) (struct fuse_conn_info *conn,
+ struct fuse_config *cfg);
+
+ /**
+ * Clean up filesystem
+ *
+ * Called on filesystem exit.
+ */
+ void (*destroy) (void *private_data);
+
+ /**
+ * Check file access permissions
+ *
+ * This will be called for the access() system call. If the
+ * 'default_permissions' mount option is given, this method is not
+ * called.
+ *
+ * This method is not called under Linux kernel versions 2.4.x
+ */
+ int (*access) (const char *, int);
+
+ /**
+ * Create and open a file
+ *
+ * If the file does not exist, first create it with the specified
+ * mode, and then open it.
+ *
+ * If this method is not implemented or under Linux kernel
+ * versions earlier than 2.6.15, the mknod() and open() methods
+ * will be called instead.
+ */
+ int (*create) (const char *, mode_t, struct fuse_file_info *);
+
+ /**
+ * Perform POSIX file locking operation
+ *
+ * The cmd argument will be either F_GETLK, F_SETLK or F_SETLKW.
+ *
+ * For the meaning of fields in 'struct flock' see the man page
+ * for fcntl(2). The l_whence field will always be set to
+ * SEEK_SET.
+ *
+ * For checking lock ownership, the 'fuse_file_info->owner'
+ * argument must be used.
+ *
+ * For F_GETLK operation, the library will first check currently
+ * held locks, and if a conflicting lock is found it will return
+ * information without calling this method. This ensures, that
+ * for local locks the l_pid field is correctly filled in. The
+ * results may not be accurate in case of race conditions and in
+ * the presence of hard links, but it's unlikely that an
+ * application would rely on accurate GETLK results in these
+ * cases. If a conflicting lock is not found, this method will be
+ * called, and the filesystem may fill out l_pid by a meaningful
+ * value, or it may leave this field zero.
+ *
+ * For F_SETLK and F_SETLKW the l_pid field will be set to the pid
+ * of the process performing the locking operation.
+ *
+ * Note: if this method is not implemented, the kernel will still
+ * allow file locking to work locally. Hence it is only
+ * interesting for network filesystems and similar.
+ */
+ int (*lock) (const char *, struct fuse_file_info *, int cmd,
+ struct flock *);
+
+ /**
+ * Change the access and modification times of a file with
+ * nanosecond resolution
+ *
+ * This supersedes the old utime() interface. New applications
+ * should use this.
+ *
+ * `fi` will always be NULL if the file is not currenlty open, but
+ * may also be NULL if the file is open.
+ *
+ * See the utimensat(2) man page for details.
+ */
+ int (*utimens) (const char *, const struct timespec tv[2],
+ struct fuse_file_info *fi);
+
+ /**
+ * Map block index within file to block index within device
+ *
+ * Note: This makes sense only for block device backed filesystems
+ * mounted with the 'blkdev' option
+ */
+ int (*bmap) (const char *, size_t blocksize, uint64_t *idx);
+
+ /**
+ * Ioctl
+ *
+ * flags will have FUSE_IOCTL_COMPAT set for 32bit ioctls in
+ * 64bit environment. The size and direction of data is
+ * determined by _IOC_*() decoding of cmd. For _IOC_NONE,
+ * data will be NULL, for _IOC_WRITE data is out area, for
+ * _IOC_READ in area and if both are set in/out area. In all
+ * non-NULL cases, the area is of _IOC_SIZE(cmd) bytes.
+ *
+ * If flags has FUSE_IOCTL_DIR then the fuse_file_info refers to a
+ * directory file handle.
+ *
+ * Note : the unsigned long request submitted by the application
+ * is truncated to 32 bits.
+ */
+ int (*ioctl) (const char *, unsigned int cmd, void *arg,
+ struct fuse_file_info *, unsigned int flags, void *data);
+
+ /**
+ * Poll for IO readiness events
+ *
+ * Note: If ph is non-NULL, the client should notify
+ * when IO readiness events occur by calling
+ * fuse_notify_poll() with the specified ph.
+ *
+ * Regardless of the number of times poll with a non-NULL ph
+ * is received, single notification is enough to clear all.
+ * Notifying more times incurs overhead but doesn't harm
+ * correctness.
+ *
+ * The callee is responsible for destroying ph with
+ * fuse_pollhandle_destroy() when no longer in use.
+ */
+ int (*poll) (const char *, struct fuse_file_info *,
+ struct fuse_pollhandle *ph, unsigned *reventsp);
+
+ /** Write contents of buffer to an open file
+ *
+ * Similar to the write() method, but data is supplied in a
+ * generic buffer. Use fuse_buf_copy() to transfer data to
+ * the destination.
+ *
+ * Unless FUSE_CAP_HANDLE_KILLPRIV is disabled, this method is
+ * expected to reset the setuid and setgid bits.
+ */
+ int (*write_buf) (const char *, struct fuse_bufvec *buf, off_t off,
+ struct fuse_file_info *);
+
+ /** Store data from an open file in a buffer
+ *
+ * Similar to the read() method, but data is stored and
+ * returned in a generic buffer.
+ *
+ * No actual copying of data has to take place, the source
+ * file descriptor may simply be stored in the buffer for
+ * later data transfer.
+ *
+ * The buffer must be allocated dynamically and stored at the
+ * location pointed to by bufp. If the buffer contains memory
+ * regions, they too must be allocated using malloc(). The
+ * allocated memory will be freed by the caller.
+ */
+ int (*read_buf) (const char *, struct fuse_bufvec **bufp,
+ size_t size, off_t off, struct fuse_file_info *);
+ /**
+ * Perform BSD file locking operation
+ *
+ * The op argument will be either LOCK_SH, LOCK_EX or LOCK_UN
+ *
+ * Nonblocking requests will be indicated by ORing LOCK_NB to
+ * the above operations
+ *
+ * For more information see the flock(2) manual page.
+ *
+ * Additionally fi->owner will be set to a value unique to
+ * this open file. This same value will be supplied to
+ * ->release() when the file is released.
+ *
+ * Note: if this method is not implemented, the kernel will still
+ * allow file locking to work locally. Hence it is only
+ * interesting for network filesystems and similar.
+ */
+ int (*flock) (const char *, struct fuse_file_info *, int op);
+
+ /**
+ * Allocates space for an open file
+ *
+ * This function ensures that required space is allocated for specified
+ * file. If this function returns success then any subsequent write
+ * request to specified range is guaranteed not to fail because of lack
+ * of space on the file system media.
+ */
+ int (*fallocate) (const char *, int, off_t, off_t,
+ struct fuse_file_info *);
+
+ /**
+ * Copy a range of data from one file to another
+ *
+ * Performs an optimized copy between two file descriptors without the
+ * additional cost of transferring data through the FUSE kernel module
+ * to user space (glibc) and then back into the FUSE filesystem again.
+ *
+ * In case this method is not implemented, glibc falls back to reading
+ * data from the source and writing to the destination. Effectively
+ * doing an inefficient copy of the data.
+ */
+ ssize_t (*copy_file_range) (const char *path_in,
+ struct fuse_file_info *fi_in,
+ off_t offset_in, const char *path_out,
+ struct fuse_file_info *fi_out,
+ off_t offset_out, size_t size, int flags);
+
+ /**
+ * Find next data or hole after the specified offset
+ */
+ off_t (*lseek) (const char *, off_t off, int whence, struct fuse_file_info *);
+};
+
+/** Extra context that may be needed by some filesystems
+ *
+ * The uid, gid and pid fields are not filled in case of a writepage
+ * operation.
+ */
+struct fuse_context {
+ /** Pointer to the fuse object */
+ struct fuse *fuse;
+
+ /** User ID of the calling process */
+ uid_t uid;
+
+ /** Group ID of the calling process */
+ gid_t gid;
+
+ /** Process ID of the calling thread */
+ pid_t pid;
+
+ /** Private filesystem data */
+ void *private_data;
+
+ /** Umask of the calling process */
+ mode_t umask;
+};
+
+/**
+ * Main function of FUSE.
+ *
+ * This is for the lazy. This is all that has to be called from the
+ * main() function.
+ *
+ * This function does the following:
+ * - parses command line options, and handles --help and
+ * --version
+ * - installs signal handlers for INT, HUP, TERM and PIPE
+ * - registers an exit handler to unmount the filesystem on program exit
+ * - creates a fuse handle
+ * - registers the operations
+ * - calls either the single-threaded or the multi-threaded event loop
+ *
+ * Most file systems will have to parse some file-system specific
+ * arguments before calling this function. It is recommended to do
+ * this with fuse_opt_parse() and a processing function that passes
+ * through any unknown options (this can also be achieved by just
+ * passing NULL as the processing function). That way, the remaining
+ * options can be passed directly to fuse_main().
+ *
+ * fuse_main() accepts all options that can be passed to
+ * fuse_parse_cmdline(), fuse_new(), or fuse_session_new().
+ *
+ * Option parsing skips argv[0], which is assumed to contain the
+ * program name. This element must always be present and is used to
+ * construct a basic ``usage: `` message for the --help
+ * output. argv[0] may also be set to the empty string. In this case
+ * the usage message is suppressed. This can be used by file systems
+ * to print their own usage line first. See hello.c for an example of
+ * how to do this.
+ *
+ * Note: this is currently implemented as a macro.
+ *
+ * The following error codes may be returned from fuse_main():
+ * 1: Invalid option arguments
+ * 2: No mount point specified
+ * 3: FUSE setup failed
+ * 4: Mounting failed
+ * 5: Failed to daemonize (detach from session)
+ * 6: Failed to set up signal handlers
+ * 7: An error occured during the life of the file system
+ *
+ * @param argc the argument counter passed to the main() function
+ * @param argv the argument vector passed to the main() function
+ * @param op the file system operation
+ * @param private_data Initial value for the `private_data`
+ * field of `struct fuse_context`. May be overridden by the
+ * `struct fuse_operations.init` handler.
+ * @return 0 on success, nonzero on failure
+ *
+ * Example usage, see hello.c
+ */
+/*
+ int fuse_main(int argc, char *argv[], const struct fuse_operations *op,
+ void *private_data);
+*/
+#define fuse_main(argc, argv, op, private_data) \
+ fuse_main_real(argc, argv, op, sizeof(*(op)), private_data)
+
+/* ----------------------------------------------------------- *
+ * More detailed API *
+ * ----------------------------------------------------------- */
+
+/**
+ * Print available options (high- and low-level) to stdout. This is
+ * not an exhaustive list, but includes only those options that may be
+ * of interest to an end-user of a file system.
+ *
+ * The function looks at the argument vector only to determine if
+ * there are additional modules to be loaded (module=foo option),
+ * and attempts to call their help functions as well.
+ *
+ * @param args the argument vector.
+ */
+void fuse_lib_help(struct fuse_args *args);
+
+/**
+ * Create a new FUSE filesystem.
+ *
+ * This function accepts most file-system independent mount options
+ * (like context, nodev, ro - see mount(8)), as well as the
+ * FUSE-specific mount options from mount.fuse(8).
+ *
+ * If the --help option is specified, the function writes a help text
+ * to stdout and returns NULL.
+ *
+ * Option parsing skips argv[0], which is assumed to contain the
+ * program name. This element must always be present and is used to
+ * construct a basic ``usage: `` message for the --help output. If
+ * argv[0] is set to the empty string, no usage message is included in
+ * the --help output.
+ *
+ * If an unknown option is passed in, an error message is written to
+ * stderr and the function returns NULL.
+ *
+ * @param args argument vector
+ * @param op the filesystem operations
+ * @param op_size the size of the fuse_operations structure
+ * @param private_data Initial value for the `private_data`
+ * field of `struct fuse_context`. May be overridden by the
+ * `struct fuse_operations.init` handler.
+ * @return the created FUSE handle
+ */
+#if FUSE_USE_VERSION == 30
+struct fuse *fuse_new_30(struct fuse_args *args, const struct fuse_operations *op,
+ size_t op_size, void *private_data);
+#define fuse_new(args, op, size, data) fuse_new_30(args, op, size, data)
+#else
+struct fuse *fuse_new(struct fuse_args *args, const struct fuse_operations *op,
+ size_t op_size, void *private_data);
+#endif
+
+/**
+ * Mount a FUSE file system.
+ *
+ * @param mountpoint the mount point path
+ * @param f the FUSE handle
+ *
+ * @return 0 on success, -1 on failure.
+ **/
+int fuse_mount(struct fuse *f, const char *mountpoint);
+
+/**
+ * Unmount a FUSE file system.
+ *
+ * See fuse_session_unmount() for additional information.
+ *
+ * @param f the FUSE handle
+ **/
+void fuse_unmount(struct fuse *f);
+
+/**
+ * Destroy the FUSE handle.
+ *
+ * NOTE: This function does not unmount the filesystem. If this is
+ * needed, call fuse_unmount() before calling this function.
+ *
+ * @param f the FUSE handle
+ */
+void fuse_destroy(struct fuse *f);
+
+/**
+ * FUSE event loop.
+ *
+ * Requests from the kernel are processed, and the appropriate
+ * operations are called.
+ *
+ * For a description of the return value and the conditions when the
+ * event loop exits, refer to the documentation of
+ * fuse_session_loop().
+ *
+ * @param f the FUSE handle
+ * @return see fuse_session_loop()
+ *
+ * See also: fuse_loop_mt()
+ */
+int fuse_loop(struct fuse *f);
+
+/**
+ * Flag session as terminated
+ *
+ * This function will cause any running event loops to exit on
+ * the next opportunity.
+ *
+ * @param f the FUSE handle
+ */
+void fuse_exit(struct fuse *f);
+
+/**
+ * FUSE event loop with multiple threads
+ *
+ * Requests from the kernel are processed, and the appropriate
+ * operations are called. Request are processed in parallel by
+ * distributing them between multiple threads.
+ *
+ * For a description of the return value and the conditions when the
+ * event loop exits, refer to the documentation of
+ * fuse_session_loop().
+ *
+ * Note: using fuse_loop() instead of fuse_loop_mt() means you are running in
+ * single-threaded mode, and that you will not have to worry about reentrancy,
+ * though you will have to worry about recursive lookups. In single-threaded
+ * mode, FUSE will wait for one callback to return before calling another.
+ *
+ * Enabling multiple threads, by using fuse_loop_mt(), will cause FUSE to make
+ * multiple simultaneous calls into the various callback functions given by your
+ * fuse_operations record.
+ *
+ * If you are using multiple threads, you can enjoy all the parallel execution
+ * and interactive response benefits of threads, and you get to enjoy all the
+ * benefits of race conditions and locking bugs, too. Ensure that any code used
+ * in the callback function of fuse_operations is also thread-safe.
+ *
+ * @param f the FUSE handle
+ * @param config loop configuration
+ * @return see fuse_session_loop()
+ *
+ * See also: fuse_loop()
+ */
+#if FUSE_USE_VERSION < 32
+int fuse_loop_mt_31(struct fuse *f, int clone_fd);
+#define fuse_loop_mt(f, clone_fd) fuse_loop_mt_31(f, clone_fd)
+#else
+int fuse_loop_mt(struct fuse *f, struct fuse_loop_config *config);
+#endif
+
+/**
+ * Get the current context
+ *
+ * The context is only valid for the duration of a filesystem
+ * operation, and thus must not be stored and used later.
+ *
+ * @return the context
+ */
+struct fuse_context *fuse_get_context(void);
+
+/**
+ * Get the current supplementary group IDs for the current request
+ *
+ * Similar to the getgroups(2) system call, except the return value is
+ * always the total number of group IDs, even if it is larger than the
+ * specified size.
+ *
+ * The current fuse kernel module in linux (as of 2.6.30) doesn't pass
+ * the group list to userspace, hence this function needs to parse
+ * "/proc/$TID/task/$TID/status" to get the group IDs.
+ *
+ * This feature may not be supported on all operating systems. In
+ * such a case this function will return -ENOSYS.
+ *
+ * @param size size of given array
+ * @param list array of group IDs to be filled in
+ * @return the total number of supplementary group IDs or -errno on failure
+ */
+int fuse_getgroups(int size, gid_t list[]);
+
+/**
+ * Check if the current request has already been interrupted
+ *
+ * @return 1 if the request has been interrupted, 0 otherwise
+ */
+int fuse_interrupted(void);
+
+/**
+ * Invalidates cache for the given path.
+ *
+ * This calls fuse_lowlevel_notify_inval_inode internally.
+ *
+ * @return 0 on successful invalidation, negative error value otherwise.
+ * This routine may return -ENOENT to indicate that there was
+ * no entry to be invalidated, e.g., because the path has not
+ * been seen before or has been forgotten; this should not be
+ * considered to be an error.
+ */
+int fuse_invalidate_path(struct fuse *f, const char *path);
+
+/**
+ * The real main function
+ *
+ * Do not call this directly, use fuse_main()
+ */
+int fuse_main_real(int argc, char *argv[], const struct fuse_operations *op,
+ size_t op_size, void *private_data);
+
+/**
+ * Start the cleanup thread when using option "remember".
+ *
+ * This is done automatically by fuse_loop_mt()
+ * @param fuse struct fuse pointer for fuse instance
+ * @return 0 on success and -1 on error
+ */
+int fuse_start_cleanup_thread(struct fuse *fuse);
+
+/**
+ * Stop the cleanup thread when using option "remember".
+ *
+ * This is done automatically by fuse_loop_mt()
+ * @param fuse struct fuse pointer for fuse instance
+ */
+void fuse_stop_cleanup_thread(struct fuse *fuse);
+
+/**
+ * Iterate over cache removing stale entries
+ * use in conjunction with "-oremember"
+ *
+ * NOTE: This is already done for the standard sessions
+ *
+ * @param fuse struct fuse pointer for fuse instance
+ * @return the number of seconds until the next cleanup
+ */
+int fuse_clean_cache(struct fuse *fuse);
+
+/*
+ * Stacking API
+ */
+
+/**
+ * Fuse filesystem object
+ *
+ * This is opaque object represents a filesystem layer
+ */
+struct fuse_fs;
+
+/*
+ * These functions call the relevant filesystem operation, and return
+ * the result.
+ *
+ * If the operation is not defined, they return -ENOSYS, with the
+ * exception of fuse_fs_open, fuse_fs_release, fuse_fs_opendir,
+ * fuse_fs_releasedir and fuse_fs_statfs, which return 0.
+ */
+
+int fuse_fs_getattr(struct fuse_fs *fs, const char *path, struct stat *buf,
+ struct fuse_file_info *fi);
+int fuse_fs_rename(struct fuse_fs *fs, const char *oldpath,
+ const char *newpath, unsigned int flags);
+int fuse_fs_unlink(struct fuse_fs *fs, const char *path);
+int fuse_fs_rmdir(struct fuse_fs *fs, const char *path);
+int fuse_fs_symlink(struct fuse_fs *fs, const char *linkname,
+ const char *path);
+int fuse_fs_link(struct fuse_fs *fs, const char *oldpath, const char *newpath);
+int fuse_fs_release(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi);
+int fuse_fs_open(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi);
+int fuse_fs_read(struct fuse_fs *fs, const char *path, char *buf, size_t size,
+ off_t off, struct fuse_file_info *fi);
+int fuse_fs_read_buf(struct fuse_fs *fs, const char *path,
+ struct fuse_bufvec **bufp, size_t size, off_t off,
+ struct fuse_file_info *fi);
+int fuse_fs_write(struct fuse_fs *fs, const char *path, const char *buf,
+ size_t size, off_t off, struct fuse_file_info *fi);
+int fuse_fs_write_buf(struct fuse_fs *fs, const char *path,
+ struct fuse_bufvec *buf, off_t off,
+ struct fuse_file_info *fi);
+int fuse_fs_fsync(struct fuse_fs *fs, const char *path, int datasync,
+ struct fuse_file_info *fi);
+int fuse_fs_flush(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi);
+int fuse_fs_statfs(struct fuse_fs *fs, const char *path, struct statvfs *buf);
+int fuse_fs_opendir(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi);
+int fuse_fs_readdir(struct fuse_fs *fs, const char *path, void *buf,
+ fuse_fill_dir_t filler, off_t off,
+ struct fuse_file_info *fi, enum fuse_readdir_flags flags);
+int fuse_fs_fsyncdir(struct fuse_fs *fs, const char *path, int datasync,
+ struct fuse_file_info *fi);
+int fuse_fs_releasedir(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi);
+int fuse_fs_create(struct fuse_fs *fs, const char *path, mode_t mode,
+ struct fuse_file_info *fi);
+int fuse_fs_lock(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi, int cmd, struct flock *lock);
+int fuse_fs_flock(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi, int op);
+int fuse_fs_chmod(struct fuse_fs *fs, const char *path, mode_t mode,
+ struct fuse_file_info *fi);
+int fuse_fs_chown(struct fuse_fs *fs, const char *path, uid_t uid, gid_t gid,
+ struct fuse_file_info *fi);
+int fuse_fs_truncate(struct fuse_fs *fs, const char *path, off_t size,
+ struct fuse_file_info *fi);
+int fuse_fs_utimens(struct fuse_fs *fs, const char *path,
+ const struct timespec tv[2], struct fuse_file_info *fi);
+int fuse_fs_access(struct fuse_fs *fs, const char *path, int mask);
+int fuse_fs_readlink(struct fuse_fs *fs, const char *path, char *buf,
+ size_t len);
+int fuse_fs_mknod(struct fuse_fs *fs, const char *path, mode_t mode,
+ dev_t rdev);
+int fuse_fs_mkdir(struct fuse_fs *fs, const char *path, mode_t mode);
+int fuse_fs_setxattr(struct fuse_fs *fs, const char *path, const char *name,
+ const char *value, size_t size, int flags);
+int fuse_fs_getxattr(struct fuse_fs *fs, const char *path, const char *name,
+ char *value, size_t size);
+int fuse_fs_listxattr(struct fuse_fs *fs, const char *path, char *list,
+ size_t size);
+int fuse_fs_removexattr(struct fuse_fs *fs, const char *path,
+ const char *name);
+int fuse_fs_bmap(struct fuse_fs *fs, const char *path, size_t blocksize,
+ uint64_t *idx);
+int fuse_fs_ioctl(struct fuse_fs *fs, const char *path, unsigned int cmd,
+ void *arg, struct fuse_file_info *fi, unsigned int flags,
+ void *data);
+int fuse_fs_poll(struct fuse_fs *fs, const char *path,
+ struct fuse_file_info *fi, struct fuse_pollhandle *ph,
+ unsigned *reventsp);
+int fuse_fs_fallocate(struct fuse_fs *fs, const char *path, int mode,
+ off_t offset, off_t length, struct fuse_file_info *fi);
+ssize_t fuse_fs_copy_file_range(struct fuse_fs *fs, const char *path_in,
+ struct fuse_file_info *fi_in, off_t off_in,
+ const char *path_out,
+ struct fuse_file_info *fi_out, off_t off_out,
+ size_t len, int flags);
+off_t fuse_fs_lseek(struct fuse_fs *fs, const char *path, off_t off, int whence,
+ struct fuse_file_info *fi);
+void fuse_fs_init(struct fuse_fs *fs, struct fuse_conn_info *conn,
+ struct fuse_config *cfg);
+void fuse_fs_destroy(struct fuse_fs *fs);
+
+int fuse_notify_poll(struct fuse_pollhandle *ph);
+
+/**
+ * Create a new fuse filesystem object
+ *
+ * This is usually called from the factory of a fuse module to create
+ * a new instance of a filesystem.
+ *
+ * @param op the filesystem operations
+ * @param op_size the size of the fuse_operations structure
+ * @param private_data Initial value for the `private_data`
+ * field of `struct fuse_context`. May be overridden by the
+ * `struct fuse_operations.init` handler.
+ * @return a new filesystem object
+ */
+struct fuse_fs *fuse_fs_new(const struct fuse_operations *op, size_t op_size,
+ void *private_data);
+
+/**
+ * Factory for creating filesystem objects
+ *
+ * The function may use and remove options from 'args' that belong
+ * to this module.
+ *
+ * For now the 'fs' vector always contains exactly one filesystem.
+ * This is the filesystem which will be below the newly created
+ * filesystem in the stack.
+ *
+ * @param args the command line arguments
+ * @param fs NULL terminated filesystem object vector
+ * @return the new filesystem object
+ */
+typedef struct fuse_fs *(*fuse_module_factory_t)(struct fuse_args *args,
+ struct fuse_fs *fs[]);
+/**
+ * Register filesystem module
+ *
+ * If the "-omodules=*name*_:..." option is present, filesystem
+ * objects are created and pushed onto the stack with the *factory_*
+ * function.
+ *
+ * @param name_ the name of this filesystem module
+ * @param factory_ the factory function for this filesystem module
+ */
+#define FUSE_REGISTER_MODULE(name_, factory_) \
+ fuse_module_factory_t fuse_module_ ## name_ ## _factory = factory_
+
+/** Get session from fuse object */
+struct fuse_session *fuse_get_session(struct fuse *f);
+
+/**
+ * Open a FUSE file descriptor and set up the mount for the given
+ * mountpoint and flags.
+ *
+ * @param mountpoint reference to the mount in the file system
+ * @param options mount options
+ * @return the FUSE file descriptor or -1 upon error
+ */
+int fuse_open_channel(const char *mountpoint, const char *options);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* FUSE_H_ */
diff --git a/tools/virtiofsd/fuse_common.h b/tools/virtiofsd/fuse_common.h
new file mode 100644
index 0000000000..2d686b2ac4
--- /dev/null
+++ b/tools/virtiofsd/fuse_common.h
@@ -0,0 +1,823 @@
+/* FUSE: Filesystem in Userspace
+ Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
+
+ This program can be distributed under the terms of the GNU LGPLv2.
+ See the file COPYING.LIB.
+*/
+
+/** @file */
+
+#if !defined(FUSE_H_) && !defined(FUSE_LOWLEVEL_H_)
+#error "Never include <fuse_common.h> directly; use <fuse.h> or <fuse_lowlevel.h> instead."
+#endif
+
+#ifndef FUSE_COMMON_H_
+#define FUSE_COMMON_H_
+
+#include "fuse_opt.h"
+#include "fuse_log.h"
+#include <stdint.h>
+#include <sys/types.h>
+
+/** Major version of FUSE library interface */
+#define FUSE_MAJOR_VERSION 3
+
+/** Minor version of FUSE library interface */
+#define FUSE_MINOR_VERSION 2
+
+#define FUSE_MAKE_VERSION(maj, min) ((maj) * 10 + (min))
+#define FUSE_VERSION FUSE_MAKE_VERSION(FUSE_MAJOR_VERSION, FUSE_MINOR_VERSION)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Information about an open file.
+ *
+ * File Handles are created by the open, opendir, and create methods and closed
+ * by the release and releasedir methods. Multiple file handles may be
+ * concurrently open for the same file. Generally, a client will create one
+ * file handle per file descriptor, though in some cases multiple file
+ * descriptors can share a single file handle.
+ */
+struct fuse_file_info {
+ /** Open flags. Available in open() and release() */
+ int flags;
+
+ /** In case of a write operation indicates if this was caused
+ by a delayed write from the page cache. If so, then the
+ context's pid, uid, and gid fields will not be valid, and
+ the *fh* value may not match the *fh* value that would
+ have been sent with the corresponding individual write
+ requests if write caching had been disabled. */
+ unsigned int writepage : 1;
+
+ /** Can be filled in by open, to use direct I/O on this file. */
+ unsigned int direct_io : 1;
+
+ /** Can be filled in by open. It signals the kernel that any
+ currently cached file data (ie., data that the filesystem
+ provided the last time the file was open) need not be
+ invalidated. Has no effect when set in other contexts (in
+ particular it does nothing when set by opendir()). */
+ unsigned int keep_cache : 1;
+
+ /** Indicates a flush operation. Set in flush operation, also
+ maybe set in highlevel lock operation and lowlevel release
+ operation. */
+ unsigned int flush : 1;
+
+ /** Can be filled in by open, to indicate that the file is not
+ seekable. */
+ unsigned int nonseekable : 1;
+
+ /* Indicates that flock locks for this file should be
+ released. If set, lock_owner shall contain a valid value.
+ May only be set in ->release(). */
+ unsigned int flock_release : 1;
+
+ /** Can be filled in by opendir. It signals the kernel to
+ enable caching of entries returned by readdir(). Has no
+ effect when set in other contexts (in particular it does
+ nothing when set by open()). */
+ unsigned int cache_readdir : 1;
+
+ /** Padding. Reserved for future use*/
+ unsigned int padding : 25;
+ unsigned int padding2 : 32;
+
+ /** File handle id. May be filled in by filesystem in create,
+ * open, and opendir(). Available in most other file operations on the
+ * same file handle. */
+ uint64_t fh;
+
+ /** Lock owner id. Available in locking operations and flush */
+ uint64_t lock_owner;
+
+ /** Requested poll events. Available in ->poll. Only set on kernels
+ which support it. If unsupported, this field is set to zero. */
+ uint32_t poll_events;
+};
+
+/**
+ * Configuration parameters passed to fuse_session_loop_mt() and
+ * fuse_loop_mt().
+ */
+struct fuse_loop_config {
+ /**
+ * whether to use separate device fds for each thread
+ * (may increase performance)
+ */
+ int clone_fd;
+
+ /**
+ * The maximum number of available worker threads before they
+ * start to get deleted when they become idle. If not
+ * specified, the default is 10.
+ *
+ * Adjusting this has performance implications; a very small number
+ * of threads in the pool will cause a lot of thread creation and
+ * deletion overhead and performance may suffer. When set to 0, a new
+ * thread will be created to service every operation.
+ */
+ unsigned int max_idle_threads;
+};
+
+/**************************************************************************
+ * Capability bits for 'fuse_conn_info.capable' and 'fuse_conn_info.want' *
+ **************************************************************************/
+
+/**
+ * Indicates that the filesystem supports asynchronous read requests.
+ *
+ * If this capability is not requested/available, the kernel will
+ * ensure that there is at most one pending read request per
+ * file-handle at any time, and will attempt to order read requests by
+ * increasing offset.
+ *
+ * This feature is enabled by default when supported by the kernel.
+ */
+#define FUSE_CAP_ASYNC_READ (1 << 0)
+
+/**
+ * Indicates that the filesystem supports "remote" locking.
+ *
+ * This feature is enabled by default when supported by the kernel,
+ * and if getlk() and setlk() handlers are implemented.
+ */
+#define FUSE_CAP_POSIX_LOCKS (1 << 1)
+
+/**
+ * Indicates that the filesystem supports the O_TRUNC open flag. If
+ * disabled, and an application specifies O_TRUNC, fuse first calls
+ * truncate() and then open() with O_TRUNC filtered out.
+ *
+ * This feature is enabled by default when supported by the kernel.
+ */
+#define FUSE_CAP_ATOMIC_O_TRUNC (1 << 3)
+
+/**
+ * Indicates that the filesystem supports lookups of "." and "..".
+ *
+ * This feature is disabled by default.
+ */
+#define FUSE_CAP_EXPORT_SUPPORT (1 << 4)
+
+/**
+ * Indicates that the kernel should not apply the umask to the
+ * file mode on create operations.
+ *
+ * This feature is disabled by default.
+ */
+#define FUSE_CAP_DONT_MASK (1 << 6)
+
+/**
+ * Indicates that libfuse should try to use splice() when writing to
+ * the fuse device. This may improve performance.
+ *
+ * This feature is disabled by default.
+ */
+#define FUSE_CAP_SPLICE_WRITE (1 << 7)
+
+/**
+ * Indicates that libfuse should try to move pages instead of copying when
+ * writing to / reading from the fuse device. This may improve performance.
+ *
+ * This feature is disabled by default.
+ */
+#define FUSE_CAP_SPLICE_MOVE (1 << 8)
+
+/**
+ * Indicates that libfuse should try to use splice() when reading from
+ * the fuse device. This may improve performance.
+ *
+ * This feature is enabled by default when supported by the kernel and
+ * if the filesystem implements a write_buf() handler.
+ */
+#define FUSE_CAP_SPLICE_READ (1 << 9)
+
+/**
+ * If set, the calls to flock(2) will be emulated using POSIX locks and must
+ * then be handled by the filesystem's setlock() handler.
+ *
+ * If not set, flock(2) calls will be handled by the FUSE kernel module
+ * internally (so any access that does not go through the kernel cannot be taken
+ * into account).
+ *
+ * This feature is enabled by default when supported by the kernel and
+ * if the filesystem implements a flock() handler.
+ */
+#define FUSE_CAP_FLOCK_LOCKS (1 << 10)
+
+/**
+ * Indicates that the filesystem supports ioctl's on directories.
+ *
+ * This feature is enabled by default when supported by the kernel.
+ */
+#define FUSE_CAP_IOCTL_DIR (1 << 11)
+
+/**
+ * Traditionally, while a file is open the FUSE kernel module only
+ * asks the filesystem for an update of the file's attributes when a
+ * client attempts to read beyond EOF. This is unsuitable for
+ * e.g. network filesystems, where the file contents may change
+ * without the kernel knowing about it.
+ *
+ * If this flag is set, FUSE will check the validity of the attributes
+ * on every read. If the attributes are no longer valid (i.e., if the
+ * *attr_timeout* passed to fuse_reply_attr() or set in `struct
+ * fuse_entry_param` has passed), it will first issue a `getattr`
+ * request. If the new mtime differs from the previous value, any
+ * cached file *contents* will be invalidated as well.
+ *
+ * This flag should always be set when available. If all file changes
+ * go through the kernel, *attr_timeout* should be set to a very large
+ * number to avoid unnecessary getattr() calls.
+ *
+ * This feature is enabled by default when supported by the kernel.
+ */
+#define FUSE_CAP_AUTO_INVAL_DATA (1 << 12)
+
+/**
+ * Indicates that the filesystem supports readdirplus.
+ *
+ * This feature is enabled by default when supported by the kernel and if the
+ * filesystem implements a readdirplus() handler.
+ */
+#define FUSE_CAP_READDIRPLUS (1 << 13)
+
+/**
+ * Indicates that the filesystem supports adaptive readdirplus.
+ *
+ * If FUSE_CAP_READDIRPLUS is not set, this flag has no effect.
+ *
+ * If FUSE_CAP_READDIRPLUS is set and this flag is not set, the kernel
+ * will always issue readdirplus() requests to retrieve directory
+ * contents.
+ *
+ * If FUSE_CAP_READDIRPLUS is set and this flag is set, the kernel
+ * will issue both readdir() and readdirplus() requests, depending on
+ * how much information is expected to be required.
+ *
+ * As of Linux 4.20, the algorithm is as follows: when userspace
+ * starts to read directory entries, issue a READDIRPLUS request to
+ * the filesystem. If any entry attributes have been looked up by the
+ * time userspace requests the next batch of entries continue with
+ * READDIRPLUS, otherwise switch to plain READDIR. This will reasult
+ * in eg plain "ls" triggering READDIRPLUS first then READDIR after
+ * that because it doesn't do lookups. "ls -l" should result in all
+ * READDIRPLUS, except if dentries are already cached.
+ *
+ * This feature is enabled by default when supported by the kernel and
+ * if the filesystem implements both a readdirplus() and a readdir()
+ * handler.
+ */
+#define FUSE_CAP_READDIRPLUS_AUTO (1 << 14)
+
+/**
+ * Indicates that the filesystem supports asynchronous direct I/O submission.
+ *
+ * If this capability is not requested/available, the kernel will ensure that
+ * there is at most one pending read and one pending write request per direct
+ * I/O file-handle at any time.
+ *
+ * This feature is enabled by default when supported by the kernel.
+ */
+#define FUSE_CAP_ASYNC_DIO (1 << 15)
+
+/**
+ * Indicates that writeback caching should be enabled. This means that
+ * individual write request may be buffered and merged in the kernel
+ * before they are send to the filesystem.
+ *
+ * This feature is disabled by default.
+ */
+#define FUSE_CAP_WRITEBACK_CACHE (1 << 16)
+
+/**
+ * Indicates support for zero-message opens. If this flag is set in
+ * the `capable` field of the `fuse_conn_info` structure, then the
+ * filesystem may return `ENOSYS` from the open() handler to indicate
+ * success. Further attempts to open files will be handled in the
+ * kernel. (If this flag is not set, returning ENOSYS will be treated
+ * as an error and signaled to the caller).
+ *
+ * Setting (or unsetting) this flag in the `want` field has *no
+ * effect*.
+ */
+#define FUSE_CAP_NO_OPEN_SUPPORT (1 << 17)
+
+/**
+ * Indicates support for parallel directory operations. If this flag
+ * is unset, the FUSE kernel module will ensure that lookup() and
+ * readdir() requests are never issued concurrently for the same
+ * directory.
+ *
+ * This feature is enabled by default when supported by the kernel.
+ */
+#define FUSE_CAP_PARALLEL_DIROPS (1 << 18)
+
+/**
+ * Indicates support for POSIX ACLs.
+ *
+ * If this feature is enabled, the kernel will cache and have
+ * responsibility for enforcing ACLs. ACL will be stored as xattrs and
+ * passed to userspace, which is responsible for updating the ACLs in
+ * the filesystem, keeping the file mode in sync with the ACL, and
+ * ensuring inheritance of default ACLs when new filesystem nodes are
+ * created. Note that this requires that the file system is able to
+ * parse and interpret the xattr representation of ACLs.
+ *
+ * Enabling this feature implicitly turns on the
+ * ``default_permissions`` mount option (even if it was not passed to
+ * mount(2)).
+ *
+ * This feature is disabled by default.
+ */
+#define FUSE_CAP_POSIX_ACL (1 << 19)
+
+/**
+ * Indicates that the filesystem is responsible for unsetting
+ * setuid and setgid bits when a file is written, truncated, or
+ * its owner is changed.
+ *
+ * This feature is enabled by default when supported by the kernel.
+ */
+#define FUSE_CAP_HANDLE_KILLPRIV (1 << 20)
+
+/**
+ * Indicates support for zero-message opendirs. If this flag is set in
+ * the `capable` field of the `fuse_conn_info` structure, then the filesystem
+ * may return `ENOSYS` from the opendir() handler to indicate success. Further
+ * opendir and releasedir messages will be handled in the kernel. (If this
+ * flag is not set, returning ENOSYS will be treated as an error and signalled
+ * to the caller.)
+ *
+ * Setting (or unsetting) this flag in the `want` field has *no effect*.
+ */
+#define FUSE_CAP_NO_OPENDIR_SUPPORT (1 << 24)
+
+/**
+ * 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_DIR: is a directory
+ *
+ * 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_DIR (1 << 4)
+
+#define FUSE_IOCTL_MAX_IOV 256
+
+/**
+ * Connection information, passed to the ->init() method
+ *
+ * Some of the elements are read-write, these can be changed to
+ * indicate the value requested by the filesystem. The requested
+ * value must usually be smaller than the indicated value.
+ */
+struct fuse_conn_info {
+ /**
+ * Major version of the protocol (read-only)
+ */
+ unsigned proto_major;
+
+ /**
+ * Minor version of the protocol (read-only)
+ */
+ unsigned proto_minor;
+
+ /**
+ * Maximum size of the write buffer
+ */
+ unsigned max_write;
+
+ /**
+ * Maximum size of read requests. A value of zero indicates no
+ * limit. However, even if the filesystem does not specify a
+ * limit, the maximum size of read requests will still be
+ * limited by the kernel.
+ *
+ * NOTE: For the time being, the maximum size of read requests
+ * must be set both here *and* passed to fuse_session_new()
+ * using the ``-o max_read=<n>`` mount option. At some point
+ * in the future, specifying the mount option will no longer
+ * be necessary.
+ */
+ unsigned max_read;
+
+ /**
+ * Maximum readahead
+ */
+ unsigned max_readahead;
+
+ /**
+ * Capability flags that the kernel supports (read-only)
+ */
+ unsigned capable;
+
+ /**
+ * Capability flags that the filesystem wants to enable.
+ *
+ * libfuse attempts to initialize this field with
+ * reasonable default values before calling the init() handler.
+ */
+ unsigned want;
+
+ /**
+ * Maximum number of pending "background" requests. A
+ * background request is any type of request for which the
+ * total number is not limited by other means. As of kernel
+ * 4.8, only two types of requests fall into this category:
+ *
+ * 1. Read-ahead requests
+ * 2. Asynchronous direct I/O requests
+ *
+ * Read-ahead requests are generated (if max_readahead is
+ * non-zero) by the kernel to preemptively fill its caches
+ * when it anticipates that userspace will soon read more
+ * data.
+ *
+ * Asynchronous direct I/O requests are generated if
+ * FUSE_CAP_ASYNC_DIO is enabled and userspace submits a large
+ * direct I/O request. In this case the kernel will internally
+ * split it up into multiple smaller requests and submit them
+ * to the filesystem concurrently.
+ *
+ * Note that the following requests are *not* background
+ * requests: writeback requests (limited by the kernel's
+ * flusher algorithm), regular (i.e., synchronous and
+ * buffered) userspace read/write requests (limited to one per
+ * thread), asynchronous read requests (Linux's io_submit(2)
+ * call actually blocks, so these are also limited to one per
+ * thread).
+ */
+ unsigned max_background;
+
+ /**
+ * Kernel congestion threshold parameter. If the number of pending
+ * background requests exceeds this number, the FUSE kernel module will
+ * mark the filesystem as "congested". This instructs the kernel to
+ * expect that queued requests will take some time to complete, and to
+ * adjust its algorithms accordingly (e.g. by putting a waiting thread
+ * to sleep instead of using a busy-loop).
+ */
+ unsigned congestion_threshold;
+
+ /**
+ * When FUSE_CAP_WRITEBACK_CACHE is enabled, the kernel is responsible
+ * for updating mtime and ctime when write requests are received. The
+ * updated values are passed to the filesystem with setattr() requests.
+ * However, if the filesystem does not support the full resolution of
+ * the kernel timestamps (nanoseconds), the mtime and ctime values used
+ * by kernel and filesystem will differ (and result in an apparent
+ * change of times after a cache flush).
+ *
+ * To prevent this problem, this variable can be used to inform the
+ * kernel about the timestamp granularity supported by the file-system.
+ * The value should be power of 10. The default is 1, i.e. full
+ * nano-second resolution. Filesystems supporting only second resolution
+ * should set this to 1000000000.
+ */
+ unsigned time_gran;
+
+ /**
+ * For future use.
+ */
+ unsigned reserved[22];
+};
+
+struct fuse_session;
+struct fuse_pollhandle;
+struct fuse_conn_info_opts;
+
+/**
+ * This function parses several command-line options that can be used
+ * to override elements of struct fuse_conn_info. The pointer returned
+ * by this function should be passed to the
+ * fuse_apply_conn_info_opts() method by the file system's init()
+ * handler.
+ *
+ * Before using this function, think twice if you really want these
+ * parameters to be adjustable from the command line. In most cases,
+ * they should be determined by the file system internally.
+ *
+ * The following options are recognized:
+ *
+ * -o max_write=N sets conn->max_write
+ * -o max_readahead=N sets conn->max_readahead
+ * -o max_background=N sets conn->max_background
+ * -o congestion_threshold=N sets conn->congestion_threshold
+ * -o async_read sets FUSE_CAP_ASYNC_READ in conn->want
+ * -o sync_read unsets FUSE_CAP_ASYNC_READ in conn->want
+ * -o atomic_o_trunc sets FUSE_CAP_ATOMIC_O_TRUNC in conn->want
+ * -o no_remote_lock Equivalent to -o no_remote_flock,no_remote_posix_lock
+ * -o no_remote_flock Unsets FUSE_CAP_FLOCK_LOCKS in conn->want
+ * -o no_remote_posix_lock Unsets FUSE_CAP_POSIX_LOCKS in conn->want
+ * -o [no_]splice_write (un-)sets FUSE_CAP_SPLICE_WRITE in conn->want
+ * -o [no_]splice_move (un-)sets FUSE_CAP_SPLICE_MOVE in conn->want
+ * -o [no_]splice_read (un-)sets FUSE_CAP_SPLICE_READ in conn->want
+ * -o [no_]auto_inval_data (un-)sets FUSE_CAP_AUTO_INVAL_DATA in conn->want
+ * -o readdirplus=no unsets FUSE_CAP_READDIRPLUS in conn->want
+ * -o readdirplus=yes sets FUSE_CAP_READDIRPLUS and unsets
+ * FUSE_CAP_READDIRPLUS_AUTO in conn->want
+ * -o readdirplus=auto sets FUSE_CAP_READDIRPLUS and
+ * FUSE_CAP_READDIRPLUS_AUTO in conn->want
+ * -o [no_]async_dio (un-)sets FUSE_CAP_ASYNC_DIO in conn->want
+ * -o [no_]writeback_cache (un-)sets FUSE_CAP_WRITEBACK_CACHE in conn->want
+ * -o time_gran=N sets conn->time_gran
+ *
+ * Known options will be removed from *args*, unknown options will be
+ * passed through unchanged.
+ *
+ * @param args argument vector (input+output)
+ * @return parsed options
+ **/
+struct fuse_conn_info_opts* fuse_parse_conn_info_opts(struct fuse_args *args);
+
+/**
+ * This function applies the (parsed) parameters in *opts* to the
+ * *conn* pointer. It may modify the following fields: wants,
+ * max_write, max_readahead, congestion_threshold, max_background,
+ * time_gran. A field is only set (or unset) if the corresponding
+ * option has been explicitly set.
+ */
+void fuse_apply_conn_info_opts(struct fuse_conn_info_opts *opts,
+ struct fuse_conn_info *conn);
+
+/**
+ * Go into the background
+ *
+ * @param foreground if true, stay in the foreground
+ * @return 0 on success, -1 on failure
+ */
+int fuse_daemonize(int foreground);
+
+/**
+ * Get the version of the library
+ *
+ * @return the version
+ */
+int fuse_version(void);
+
+/**
+ * Get the full package version string of the library
+ *
+ * @return the package version
+ */
+const char *fuse_pkgversion(void);
+
+/**
+ * Destroy poll handle
+ *
+ * @param ph the poll handle
+ */
+void fuse_pollhandle_destroy(struct fuse_pollhandle *ph);
+
+/* ----------------------------------------------------------- *
+ * Data buffer *
+ * ----------------------------------------------------------- */
+
+/**
+ * Buffer flags
+ */
+enum fuse_buf_flags {
+ /**
+ * Buffer contains a file descriptor
+ *
+ * If this flag is set, the .fd field is valid, otherwise the
+ * .mem fields is valid.
+ */
+ FUSE_BUF_IS_FD = (1 << 1),
+
+ /**
+ * Seek on the file descriptor
+ *
+ * If this flag is set then the .pos field is valid and is
+ * used to seek to the given offset before performing
+ * operation on file descriptor.
+ */
+ FUSE_BUF_FD_SEEK = (1 << 2),
+
+ /**
+ * Retry operation on file descriptor
+ *
+ * If this flag is set then retry operation on file descriptor
+ * until .size bytes have been copied or an error or EOF is
+ * detected.
+ */
+ FUSE_BUF_FD_RETRY = (1 << 3),
+};
+
+/**
+ * Buffer copy flags
+ */
+enum fuse_buf_copy_flags {
+ /**
+ * Don't use splice(2)
+ *
+ * Always fall back to using read and write instead of
+ * splice(2) to copy data from one file descriptor to another.
+ *
+ * If this flag is not set, then only fall back if splice is
+ * unavailable.
+ */
+ FUSE_BUF_NO_SPLICE = (1 << 1),
+
+ /**
+ * Force splice
+ *
+ * Always use splice(2) to copy data from one file descriptor
+ * to another. If splice is not available, return -EINVAL.
+ */
+ FUSE_BUF_FORCE_SPLICE = (1 << 2),
+
+ /**
+ * Try to move data with splice.
+ *
+ * If splice is used, try to move pages from the source to the
+ * destination instead of copying. See documentation of
+ * SPLICE_F_MOVE in splice(2) man page.
+ */
+ FUSE_BUF_SPLICE_MOVE = (1 << 3),
+
+ /**
+ * Don't block on the pipe when copying data with splice
+ *
+ * Makes the operations on the pipe non-blocking (if the pipe
+ * is full or empty). See SPLICE_F_NONBLOCK in the splice(2)
+ * man page.
+ */
+ FUSE_BUF_SPLICE_NONBLOCK= (1 << 4),
+};
+
+/**
+ * Single data buffer
+ *
+ * Generic data buffer for I/O, extended attributes, etc... Data may
+ * be supplied as a memory pointer or as a file descriptor
+ */
+struct fuse_buf {
+ /**
+ * Size of data in bytes
+ */
+ size_t size;
+
+ /**
+ * Buffer flags
+ */
+ enum fuse_buf_flags flags;
+
+ /**
+ * Memory pointer
+ *
+ * Used unless FUSE_BUF_IS_FD flag is set.
+ */
+ void *mem;
+
+ /**
+ * File descriptor
+ *
+ * Used if FUSE_BUF_IS_FD flag is set.
+ */
+ int fd;
+
+ /**
+ * File position
+ *
+ * Used if FUSE_BUF_FD_SEEK flag is set.
+ */
+ off_t pos;
+};
+
+/**
+ * Data buffer vector
+ *
+ * An array of data buffers, each containing a memory pointer or a
+ * file descriptor.
+ *
+ * Allocate dynamically to add more than one buffer.
+ */
+struct fuse_bufvec {
+ /**
+ * Number of buffers in the array
+ */
+ size_t count;
+
+ /**
+ * Index of current buffer within the array
+ */
+ size_t idx;
+
+ /**
+ * Current offset within the current buffer
+ */
+ size_t off;
+
+ /**
+ * Array of buffers
+ */
+ struct fuse_buf buf[1];
+};
+
+/* Initialize bufvec with a single buffer of given size */
+#define FUSE_BUFVEC_INIT(size__) \
+ ((struct fuse_bufvec) { \
+ /* .count= */ 1, \
+ /* .idx = */ 0, \
+ /* .off = */ 0, \
+ /* .buf = */ { /* [0] = */ { \
+ /* .size = */ (size__), \
+ /* .flags = */ (enum fuse_buf_flags) 0, \
+ /* .mem = */ NULL, \
+ /* .fd = */ -1, \
+ /* .pos = */ 0, \
+ } } \
+ } )
+
+/**
+ * Get total size of data in a fuse buffer vector
+ *
+ * @param bufv buffer vector
+ * @return size of data
+ */
+size_t fuse_buf_size(const struct fuse_bufvec *bufv);
+
+/**
+ * Copy data from one buffer vector to another
+ *
+ * @param dst destination buffer vector
+ * @param src source buffer vector
+ * @param flags flags controlling the copy
+ * @return actual number of bytes copied or -errno on error
+ */
+ssize_t fuse_buf_copy(struct fuse_bufvec *dst, struct fuse_bufvec *src,
+ enum fuse_buf_copy_flags flags);
+
+/* ----------------------------------------------------------- *
+ * Signal handling *
+ * ----------------------------------------------------------- */
+
+/**
+ * Exit session on HUP, TERM and INT signals and ignore PIPE signal
+ *
+ * Stores session in a global variable. May only be called once per
+ * process until fuse_remove_signal_handlers() is called.
+ *
+ * Once either of the POSIX signals arrives, the signal handler calls
+ * fuse_session_exit().
+ *
+ * @param se the session to exit
+ * @return 0 on success, -1 on failure
+ *
+ * See also:
+ * fuse_remove_signal_handlers()
+ */
+int fuse_set_signal_handlers(struct fuse_session *se);
+
+/**
+ * Restore default signal handlers
+ *
+ * Resets global session. After this fuse_set_signal_handlers() may
+ * be called again.
+ *
+ * @param se the same session as given in fuse_set_signal_handlers()
+ *
+ * See also:
+ * fuse_set_signal_handlers()
+ */
+void fuse_remove_signal_handlers(struct fuse_session *se);
+
+/* ----------------------------------------------------------- *
+ * Compatibility stuff *
+ * ----------------------------------------------------------- */
+
+#if !defined(FUSE_USE_VERSION) || FUSE_USE_VERSION < 30
+# error only API version 30 or greater is supported
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+
+/*
+ * This interface uses 64 bit off_t.
+ *
+ * On 32bit systems please add -D_FILE_OFFSET_BITS=64 to your compile flags!
+ */
+
+#if defined(__GNUC__) && (__GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ >= 6) && !defined __cplusplus
+_Static_assert(sizeof(off_t) == 8, "fuse: off_t must be 64bit");
+#else
+struct _fuse_off_t_must_be_64bit_dummy_struct \
+ { unsigned _fuse_off_t_must_be_64bit:((sizeof(off_t) == 8) ? 1 : -1); };
+#endif
+
+#endif /* FUSE_COMMON_H_ */
diff --git a/tools/virtiofsd/fuse_i.h b/tools/virtiofsd/fuse_i.h
new file mode 100644
index 0000000000..d38b630ac5
--- /dev/null
+++ b/tools/virtiofsd/fuse_i.h
@@ -0,0 +1,139 @@
+/*
+ FUSE: Filesystem in Userspace
+ Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
+
+ This program can be distributed under the terms of the GNU LGPLv2.
+ See the file COPYING.LIB
+*/
+
+#include "fuse.h"
+#include "fuse_lowlevel.h"
+
+struct mount_opts;
+
+struct fuse_req {
+ struct fuse_session *se;
+ uint64_t unique;
+ int ctr;
+ pthread_mutex_t lock;
+ struct fuse_ctx ctx;
+ struct fuse_chan *ch;
+ int interrupted;
+ unsigned int ioctl_64bit : 1;
+ union {
+ struct {
+ uint64_t unique;
+ } i;
+ struct {
+ fuse_interrupt_func_t func;
+ void *data;
+ } ni;
+ } u;
+ struct fuse_req *next;
+ struct fuse_req *prev;
+};
+
+struct fuse_notify_req {
+ uint64_t unique;
+ void (*reply)(struct fuse_notify_req *, fuse_req_t, fuse_ino_t,
+ const void *, const struct fuse_buf *);
+ struct fuse_notify_req *next;
+ struct fuse_notify_req *prev;
+};
+
+struct fuse_session {
+ char *mountpoint;
+ volatile int exited;
+ int fd;
+ struct mount_opts *mo;
+ int debug;
+ int deny_others;
+ struct fuse_lowlevel_ops op;
+ int got_init;
+ struct cuse_data *cuse_data;
+ void *userdata;
+ uid_t owner;
+ struct fuse_conn_info conn;
+ struct fuse_req list;
+ struct fuse_req interrupts;
+ pthread_mutex_t lock;
+ int got_destroy;
+ pthread_key_t pipe_key;
+ int broken_splice_nonblock;
+ uint64_t notify_ctr;
+ struct fuse_notify_req notify_list;
+ size_t bufsize;
+ int error;
+};
+
+struct fuse_chan {
+ pthread_mutex_t lock;
+ int ctr;
+ int fd;
+};
+
+/**
+ * Filesystem module
+ *
+ * Filesystem modules are registered with the FUSE_REGISTER_MODULE()
+ * macro.
+ *
+ */
+struct fuse_module {
+ char *name;
+ fuse_module_factory_t factory;
+ struct fuse_module *next;
+ struct fusemod_so *so;
+ int ctr;
+};
+
+/* ----------------------------------------------------------- *
+ * Channel interface (when using -o clone_fd) *
+ * ----------------------------------------------------------- */
+
+/**
+ * Obtain counted reference to the channel
+ *
+ * @param ch the channel
+ * @return the channel
+ */
+struct fuse_chan *fuse_chan_get(struct fuse_chan *ch);
+
+/**
+ * Drop counted reference to a channel
+ *
+ * @param ch the channel
+ */
+void fuse_chan_put(struct fuse_chan *ch);
+
+struct mount_opts *parse_mount_opts(struct fuse_args *args);
+void destroy_mount_opts(struct mount_opts *mo);
+void fuse_mount_version(void);
+unsigned get_max_read(struct mount_opts *o);
+void fuse_kern_unmount(const char *mountpoint, int fd);
+int fuse_kern_mount(const char *mountpoint, struct mount_opts *mo);
+
+int fuse_send_reply_iov_nofree(fuse_req_t req, int error, struct iovec *iov,
+ int count);
+void fuse_free_req(fuse_req_t req);
+
+void cuse_lowlevel_init(fuse_req_t req, fuse_ino_t nodeide, const void *inarg);
+
+int fuse_start_thread(pthread_t *thread_id, void *(*func)(void *), void *arg);
+
+int fuse_session_receive_buf_int(struct fuse_session *se, struct fuse_buf *buf,
+ struct fuse_chan *ch);
+void fuse_session_process_buf_int(struct fuse_session *se,
+ const struct fuse_buf *buf, struct fuse_chan *ch);
+
+struct fuse *fuse_new_31(struct fuse_args *args, const struct fuse_operations *op,
+ size_t op_size, void *private_data);
+int fuse_loop_mt_32(struct fuse *f, struct fuse_loop_config *config);
+int fuse_session_loop_mt_32(struct fuse_session *se, struct fuse_loop_config *config);
+
+#define FUSE_MAX_MAX_PAGES 256
+#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32
+
+/* room needed in buffer to accommodate header */
+#define FUSE_BUFFER_HEADER_SIZE 0x1000
+
diff --git a/tools/virtiofsd/fuse_log.h b/tools/virtiofsd/fuse_log.h
new file mode 100644
index 0000000000..5e112e0f53
--- /dev/null
+++ b/tools/virtiofsd/fuse_log.h
@@ -0,0 +1,82 @@
+/*
+ FUSE: Filesystem in Userspace
+ Copyright (C) 2019 Red Hat, Inc.
+
+ This program can be distributed under the terms of the GNU LGPLv2.
+ See the file COPYING.LIB.
+*/
+
+#ifndef FUSE_LOG_H_
+#define FUSE_LOG_H_
+
+/** @file
+ *
+ * This file defines the logging interface of FUSE
+ */
+
+#include <stdarg.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Log severity level
+ *
+ * These levels correspond to syslog(2) log levels since they are widely used.
+ */
+enum fuse_log_level {
+ FUSE_LOG_EMERG,
+ FUSE_LOG_ALERT,
+ FUSE_LOG_CRIT,
+ FUSE_LOG_ERR,
+ FUSE_LOG_WARNING,
+ FUSE_LOG_NOTICE,
+ FUSE_LOG_INFO,
+ FUSE_LOG_DEBUG
+};
+
+/**
+ * Log message handler function.
+ *
+ * This function must be thread-safe. It may be called from any libfuse
+ * function, including fuse_parse_cmdline() and other functions invoked before
+ * a FUSE filesystem is created.
+ *
+ * Install a custom log message handler function using fuse_set_log_func().
+ *
+ * @param level log severity level
+ * @param fmt sprintf-style format string including newline
+ * @param ap format string arguments
+ */
+typedef void (*fuse_log_func_t)(enum fuse_log_level level,
+ const char *fmt, va_list ap);
+
+/**
+ * Install a custom log handler function.
+ *
+ * Log messages are emitted by libfuse functions to report errors and debug
+ * information. Messages are printed to stderr by default but this can be
+ * overridden by installing a custom log message handler function.
+ *
+ * The log message handler function is global and affects all FUSE filesystems
+ * created within this process.
+ *
+ * @param func a custom log message handler function or NULL to revert to
+ * the default
+ */
+void fuse_set_log_func(fuse_log_func_t func);
+
+/**
+ * Emit a log message
+ *
+ * @param level severity level (FUSE_LOG_ERR, FUSE_LOG_DEBUG, etc)
+ * @param fmt sprintf-style format string including newline
+ */
+void fuse_log(enum fuse_log_level level, const char *fmt, ...);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* FUSE_LOG_H_ */
diff --git a/tools/virtiofsd/fuse_lowlevel.h b/tools/virtiofsd/fuse_lowlevel.h
new file mode 100644
index 0000000000..18c6363f07
--- /dev/null
+++ b/tools/virtiofsd/fuse_lowlevel.h
@@ -0,0 +1,2089 @@
+/*
+ FUSE: Filesystem in Userspace
+ Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
+
+ This program can be distributed under the terms of the GNU LGPLv2.
+ See the file COPYING.LIB.
+*/
+
+#ifndef FUSE_LOWLEVEL_H_
+#define FUSE_LOWLEVEL_H_
+
+/** @file
+ *
+ * Low level API
+ *
+ * IMPORTANT: you should define FUSE_USE_VERSION before including this
+ * header. To use the newest API define it to 31 (recommended for any
+ * new application).
+ */
+
+#ifndef FUSE_USE_VERSION
+#error FUSE_USE_VERSION not defined
+#endif
+
+#include "fuse_common.h"
+
+#include <utime.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include <sys/uio.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* ----------------------------------------------------------- *
+ * Miscellaneous definitions *
+ * ----------------------------------------------------------- */
+
+/** The node ID of the root inode */
+#define FUSE_ROOT_ID 1
+
+/** Inode number type */
+typedef uint64_t fuse_ino_t;
+
+/** Request pointer type */
+typedef struct fuse_req *fuse_req_t;
+
+/**
+ * Session
+ *
+ * This provides hooks for processing requests, and exiting
+ */
+struct fuse_session;
+
+/** Directory entry parameters supplied to fuse_reply_entry() */
+struct fuse_entry_param {
+ /** Unique inode number
+ *
+ * In lookup, zero means negative entry (from version 2.5)
+ * Returning ENOENT also means negative entry, but by setting zero
+ * ino the kernel may cache negative entries for entry_timeout
+ * seconds.
+ */
+ fuse_ino_t ino;
+
+ /** Generation number for this entry.
+ *
+ * If the file system will be exported over NFS, the
+ * ino/generation pairs need to be unique over the file
+ * system's lifetime (rather than just the mount time). So if
+ * the file system reuses an inode after it has been deleted,
+ * it must assign a new, previously unused generation number
+ * to the inode at the same time.
+ *
+ */
+ uint64_t generation;
+
+ /** Inode attributes.
+ *
+ * Even if attr_timeout == 0, attr must be correct. For example,
+ * for open(), FUSE uses attr.st_size from lookup() to determine
+ * how many bytes to request. If this value is not correct,
+ * incorrect data will be returned.
+ */
+ struct stat attr;
+
+ /** Validity timeout (in seconds) for inode attributes. If
+ attributes only change as a result of requests that come
+ through the kernel, this should be set to a very large
+ value. */
+ double attr_timeout;
+
+ /** Validity timeout (in seconds) for the name. If directory
+ entries are changed/deleted only as a result of requests
+ that come through the kernel, this should be set to a very
+ large value. */
+ double entry_timeout;
+};
+
+/**
+ * Additional context associated with requests.
+ *
+ * Note that the reported client uid, gid and pid may be zero in some
+ * situations. For example, if the FUSE file system is running in a
+ * PID or user namespace but then accessed from outside the namespace,
+ * there is no valid uid/pid/gid that could be reported.
+ */
+struct fuse_ctx {
+ /** User ID of the calling process */
+ uid_t uid;
+
+ /** Group ID of the calling process */
+ gid_t gid;
+
+ /** Thread ID of the calling process */
+ pid_t pid;
+
+ /** Umask of the calling process */
+ mode_t umask;
+};
+
+struct fuse_forget_data {
+ fuse_ino_t ino;
+ uint64_t nlookup;
+};
+
+/* 'to_set' flags in setattr */
+#define FUSE_SET_ATTR_MODE (1 << 0)
+#define FUSE_SET_ATTR_UID (1 << 1)
+#define FUSE_SET_ATTR_GID (1 << 2)
+#define FUSE_SET_ATTR_SIZE (1 << 3)
+#define FUSE_SET_ATTR_ATIME (1 << 4)
+#define FUSE_SET_ATTR_MTIME (1 << 5)
+#define FUSE_SET_ATTR_ATIME_NOW (1 << 7)
+#define FUSE_SET_ATTR_MTIME_NOW (1 << 8)
+#define FUSE_SET_ATTR_CTIME (1 << 10)
+
+/* ----------------------------------------------------------- *
+ * Request methods and replies *
+ * ----------------------------------------------------------- */
+
+/**
+ * Low level filesystem operations
+ *
+ * Most of the methods (with the exception of init and destroy)
+ * receive a request handle (fuse_req_t) as their first argument.
+ * This handle must be passed to one of the specified reply functions.
+ *
+ * This may be done inside the method invocation, or after the call
+ * has returned. The request handle is valid until one of the reply
+ * functions is called.
+ *
+ * Other pointer arguments (name, fuse_file_info, etc) are not valid
+ * after the call has returned, so if they are needed later, their
+ * contents have to be copied.
+ *
+ * In general, all methods are expected to perform any necessary
+ * permission checking. However, a filesystem may delegate this task
+ * to the kernel by passing the `default_permissions` mount option to
+ * `fuse_session_new()`. In this case, methods will only be called if
+ * the kernel's permission check has succeeded.
+ *
+ * The filesystem sometimes needs to handle a return value of -ENOENT
+ * from the reply function, which means, that the request was
+ * interrupted, and the reply discarded. For example if
+ * fuse_reply_open() return -ENOENT means, that the release method for
+ * this file will not be called.
+ */
+struct fuse_lowlevel_ops {
+ /**
+ * Initialize filesystem
+ *
+ * This function is called when libfuse establishes
+ * communication with the FUSE kernel module. The file system
+ * should use this module to inspect and/or modify the
+ * connection parameters provided in the `conn` structure.
+ *
+ * Note that some parameters may be overwritten by options
+ * passed to fuse_session_new() which take precedence over the
+ * values set in this handler.
+ *
+ * There's no reply to this function
+ *
+ * @param userdata the user data passed to fuse_session_new()
+ */
+ void (*init) (void *userdata, struct fuse_conn_info *conn);
+
+ /**
+ * Clean up filesystem.
+ *
+ * Called on filesystem exit. When this method is called, the
+ * connection to the kernel may be gone already, so that eg. calls
+ * to fuse_lowlevel_notify_* will fail.
+ *
+ * There's no reply to this function
+ *
+ * @param userdata the user data passed to fuse_session_new()
+ */
+ void (*destroy) (void *userdata);
+
+ /**
+ * Look up a directory entry by name and get its attributes.
+ *
+ * Valid replies:
+ * fuse_reply_entry
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param parent inode number of the parent directory
+ * @param name the name to look up
+ */
+ void (*lookup) (fuse_req_t req, fuse_ino_t parent, const char *name);
+
+ /**
+ * Forget about an inode
+ *
+ * This function is called when the kernel removes an inode
+ * from its internal caches.
+ *
+ * The inode's lookup count increases by one for every call to
+ * fuse_reply_entry and fuse_reply_create. The nlookup parameter
+ * indicates by how much the lookup count should be decreased.
+ *
+ * Inodes with a non-zero lookup count may receive request from
+ * the kernel even after calls to unlink, rmdir or (when
+ * overwriting an existing file) rename. Filesystems must handle
+ * such requests properly and it is recommended to defer removal
+ * of the inode until the lookup count reaches zero. Calls to
+ * unlink, rmdir or rename will be followed closely by forget
+ * unless the file or directory is open, in which case the
+ * kernel issues forget only after the release or releasedir
+ * calls.
+ *
+ * Note that if a file system will be exported over NFS the
+ * inodes lifetime must extend even beyond forget. See the
+ * generation field in struct fuse_entry_param above.
+ *
+ * On unmount the lookup count for all inodes implicitly drops
+ * to zero. It is not guaranteed that the file system will
+ * receive corresponding forget messages for the affected
+ * inodes.
+ *
+ * Valid replies:
+ * fuse_reply_none
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param nlookup the number of lookups to forget
+ */
+ void (*forget) (fuse_req_t req, fuse_ino_t ino, uint64_t nlookup);
+
+ /**
+ * Get file attributes.
+ *
+ * If writeback caching is enabled, the kernel may have a
+ * better idea of a file's length than the FUSE file system
+ * (eg if there has been a write that extended the file size,
+ * but that has not yet been passed to the filesystem.n
+ *
+ * In this case, the st_size value provided by the file system
+ * will be ignored.
+ *
+ * Valid replies:
+ * fuse_reply_attr
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi for future use, currently always NULL
+ */
+ void (*getattr) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi);
+
+ /**
+ * Set file attributes
+ *
+ * In the 'attr' argument only members indicated by the 'to_set'
+ * bitmask contain valid values. Other members contain undefined
+ * values.
+ *
+ * Unless FUSE_CAP_HANDLE_KILLPRIV is disabled, this method is
+ * expected to reset the setuid and setgid bits if the file
+ * size or owner is being changed.
+ *
+ * If the setattr was invoked from the ftruncate() system call
+ * under Linux kernel versions 2.6.15 or later, the fi->fh will
+ * contain the value set by the open method or will be undefined
+ * if the open method didn't set any value. Otherwise (not
+ * ftruncate call, or kernel version earlier than 2.6.15) the fi
+ * parameter will be NULL.
+ *
+ * Valid replies:
+ * fuse_reply_attr
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param attr the attributes
+ * @param to_set bit mask of attributes which should be set
+ * @param fi file information, or NULL
+ */
+ void (*setattr) (fuse_req_t req, fuse_ino_t ino, struct stat *attr,
+ int to_set, struct fuse_file_info *fi);
+
+ /**
+ * Read symbolic link
+ *
+ * Valid replies:
+ * fuse_reply_readlink
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ */
+ void (*readlink) (fuse_req_t req, fuse_ino_t ino);
+
+ /**
+ * Create file node
+ *
+ * Create a regular file, character device, block device, fifo or
+ * socket node.
+ *
+ * Valid replies:
+ * fuse_reply_entry
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param parent inode number of the parent directory
+ * @param name to create
+ * @param mode file type and mode with which to create the new file
+ * @param rdev the device number (only valid if created file is a device)
+ */
+ void (*mknod) (fuse_req_t req, fuse_ino_t parent, const char *name,
+ mode_t mode, dev_t rdev);
+
+ /**
+ * Create a directory
+ *
+ * Valid replies:
+ * fuse_reply_entry
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param parent inode number of the parent directory
+ * @param name to create
+ * @param mode with which to create the new file
+ */
+ void (*mkdir) (fuse_req_t req, fuse_ino_t parent, const char *name,
+ mode_t mode);
+
+ /**
+ * Remove a file
+ *
+ * If the file's inode's lookup count is non-zero, the file
+ * system is expected to postpone any removal of the inode
+ * until the lookup count reaches zero (see description of the
+ * forget function).
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param parent inode number of the parent directory
+ * @param name to remove
+ */
+ void (*unlink) (fuse_req_t req, fuse_ino_t parent, const char *name);
+
+ /**
+ * Remove a directory
+ *
+ * If the directory's inode's lookup count is non-zero, the
+ * file system is expected to postpone any removal of the
+ * inode until the lookup count reaches zero (see description
+ * of the forget function).
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param parent inode number of the parent directory
+ * @param name to remove
+ */
+ void (*rmdir) (fuse_req_t req, fuse_ino_t parent, const char *name);
+
+ /**
+ * Create a symbolic link
+ *
+ * Valid replies:
+ * fuse_reply_entry
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param link the contents of the symbolic link
+ * @param parent inode number of the parent directory
+ * @param name to create
+ */
+ void (*symlink) (fuse_req_t req, const char *link, fuse_ino_t parent,
+ const char *name);
+
+ /** Rename a file
+ *
+ * If the target exists it should be atomically replaced. If
+ * the target's inode's lookup count is non-zero, the file
+ * system is expected to postpone any removal of the inode
+ * until the lookup count reaches zero (see description of the
+ * forget function).
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure with error code EINVAL, i.e. all
+ * future bmap requests will fail with EINVAL without being
+ * send to the filesystem process.
+ *
+ * *flags* may be `RENAME_EXCHANGE` or `RENAME_NOREPLACE`. If
+ * RENAME_NOREPLACE is specified, the filesystem must not
+ * overwrite *newname* if it exists and return an error
+ * instead. If `RENAME_EXCHANGE` is specified, the filesystem
+ * must atomically exchange the two files, i.e. both must
+ * exist and neither may be deleted.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param parent inode number of the old parent directory
+ * @param name old name
+ * @param newparent inode number of the new parent directory
+ * @param newname new name
+ */
+ void (*rename) (fuse_req_t req, fuse_ino_t parent, const char *name,
+ fuse_ino_t newparent, const char *newname,
+ unsigned int flags);
+
+ /**
+ * Create a hard link
+ *
+ * Valid replies:
+ * fuse_reply_entry
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the old inode number
+ * @param newparent inode number of the new parent directory
+ * @param newname new name to create
+ */
+ void (*link) (fuse_req_t req, fuse_ino_t ino, fuse_ino_t newparent,
+ const char *newname);
+
+ /**
+ * Open a file
+ *
+ * Open flags are available in fi->flags. The following rules
+ * apply.
+ *
+ * - Creation (O_CREAT, O_EXCL, O_NOCTTY) flags will be
+ * filtered out / handled by the kernel.
+ *
+ * - Access modes (O_RDONLY, O_WRONLY, O_RDWR) should be used
+ * by the filesystem to check if the operation is
+ * permitted. If the ``-o default_permissions`` mount
+ * option is given, this check is already done by the
+ * kernel before calling open() and may thus be omitted by
+ * the filesystem.
+ *
+ * - When writeback caching is enabled, the kernel may send
+ * read requests even for files opened with O_WRONLY. The
+ * filesystem should be prepared to handle this.
+ *
+ * - When writeback caching is disabled, the filesystem is
+ * expected to properly handle the O_APPEND flag and ensure
+ * that each write is appending to the end of the file.
+ *
+ * - When writeback caching is enabled, the kernel will
+ * handle O_APPEND. However, unless all changes to the file
+ * come through the kernel this will not work reliably. The
+ * filesystem should thus either ignore the O_APPEND flag
+ * (and let the kernel handle it), or return an error
+ * (indicating that reliably O_APPEND is not available).
+ *
+ * Filesystem may store an arbitrary file handle (pointer,
+ * index, etc) in fi->fh, and use this in other all other file
+ * operations (read, write, flush, release, fsync).
+ *
+ * Filesystem may also implement stateless file I/O and not store
+ * anything in fi->fh.
+ *
+ * There are also some flags (direct_io, keep_cache) which the
+ * filesystem may set in fi, to change the way the file is opened.
+ * See fuse_file_info structure in <fuse_common.h> for more details.
+ *
+ * If this request is answered with an error code of ENOSYS
+ * and FUSE_CAP_NO_OPEN_SUPPORT is set in
+ * `fuse_conn_info.capable`, this is treated as success and
+ * future calls to open and release will also succeed without being
+ * sent to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_open
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ */
+ void (*open) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi);
+
+ /**
+ * Read data
+ *
+ * Read should send exactly the number of bytes requested except
+ * on EOF or error, otherwise the rest of the data will be
+ * substituted with zeroes. An exception to this is when the file
+ * has been opened in 'direct_io' mode, in which case the return
+ * value of the read system call will reflect the return value of
+ * this operation.
+ *
+ * fi->fh will contain the value set by the open method, or will
+ * be undefined if the open method didn't set any value.
+ *
+ * Valid replies:
+ * fuse_reply_buf
+ * fuse_reply_iov
+ * fuse_reply_data
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param size number of bytes to read
+ * @param off offset to read from
+ * @param fi file information
+ */
+ void (*read) (fuse_req_t req, fuse_ino_t ino, size_t size, off_t off,
+ struct fuse_file_info *fi);
+
+ /**
+ * Write data
+ *
+ * Write should return exactly the number of bytes requested
+ * except on error. An exception to this is when the file has
+ * been opened in 'direct_io' mode, in which case the return value
+ * of the write system call will reflect the return value of this
+ * operation.
+ *
+ * Unless FUSE_CAP_HANDLE_KILLPRIV is disabled, this method is
+ * expected to reset the setuid and setgid bits.
+ *
+ * fi->fh will contain the value set by the open method, or will
+ * be undefined if the open method didn't set any value.
+ *
+ * Valid replies:
+ * fuse_reply_write
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param buf data to write
+ * @param size number of bytes to write
+ * @param off offset to write to
+ * @param fi file information
+ */
+ void (*write) (fuse_req_t req, fuse_ino_t ino, const char *buf,
+ size_t size, off_t off, struct fuse_file_info *fi);
+
+ /**
+ * Flush method
+ *
+ * This is called on each close() of the opened file.
+ *
+ * Since file descriptors can be duplicated (dup, dup2, fork), for
+ * one open call there may be many flush calls.
+ *
+ * Filesystems shouldn't assume that flush will always be called
+ * after some writes, or that if will be called at all.
+ *
+ * fi->fh will contain the value set by the open method, or will
+ * be undefined if the open method didn't set any value.
+ *
+ * NOTE: the name of the method is misleading, since (unlike
+ * fsync) the filesystem is not forced to flush pending writes.
+ * One reason to flush data is if the filesystem wants to return
+ * write errors during close. However, such use is non-portable
+ * because POSIX does not require [close] to wait for delayed I/O to
+ * complete.
+ *
+ * If the filesystem supports file locking operations (setlk,
+ * getlk) it should remove all locks belonging to 'fi->owner'.
+ *
+ * If this request is answered with an error code of ENOSYS,
+ * this is treated as success and future calls to flush() will
+ * succeed automatically without being send to the filesystem
+ * process.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ *
+ * [close]: http://pubs.opengroup.org/onlinepubs/9699919799/functions/close.html
+ */
+ void (*flush) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi);
+
+ /**
+ * Release an open file
+ *
+ * Release is called when there are no more references to an open
+ * file: all file descriptors are closed and all memory mappings
+ * are unmapped.
+ *
+ * For every open call there will be exactly one release call (unless
+ * the filesystem is force-unmounted).
+ *
+ * The filesystem may reply with an error, but error values are
+ * not returned to close() or munmap() which triggered the
+ * release.
+ *
+ * fi->fh will contain the value set by the open method, or will
+ * be undefined if the open method didn't set any value.
+ * fi->flags will contain the same flags as for open.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ */
+ void (*release) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi);
+
+ /**
+ * Synchronize file contents
+ *
+ * If the datasync parameter is non-zero, then only the user data
+ * should be flushed, not the meta data.
+ *
+ * If this request is answered with an error code of ENOSYS,
+ * this is treated as success and future calls to fsync() will
+ * succeed automatically without being send to the filesystem
+ * process.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param datasync flag indicating if only data should be flushed
+ * @param fi file information
+ */
+ void (*fsync) (fuse_req_t req, fuse_ino_t ino, int datasync,
+ struct fuse_file_info *fi);
+
+ /**
+ * Open a directory
+ *
+ * Filesystem may store an arbitrary file handle (pointer, index,
+ * etc) in fi->fh, and use this in other all other directory
+ * stream operations (readdir, releasedir, fsyncdir).
+ *
+ * If this request is answered with an error code of ENOSYS and
+ * FUSE_CAP_NO_OPENDIR_SUPPORT is set in `fuse_conn_info.capable`,
+ * this is treated as success and future calls to opendir and
+ * releasedir will also succeed without being sent to the filesystem
+ * process. In addition, the kernel will cache readdir results
+ * as if opendir returned FOPEN_KEEP_CACHE | FOPEN_CACHE_DIR.
+ *
+ * Valid replies:
+ * fuse_reply_open
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ */
+ void (*opendir) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi);
+
+ /**
+ * Read directory
+ *
+ * Send a buffer filled using fuse_add_direntry(), with size not
+ * exceeding the requested size. Send an empty buffer on end of
+ * stream.
+ *
+ * fi->fh will contain the value set by the opendir method, or
+ * will be undefined if the opendir method didn't set any value.
+ *
+ * Returning a directory entry from readdir() does not affect
+ * its lookup count.
+ *
+ * If off_t is non-zero, then it will correspond to one of the off_t
+ * values that was previously returned by readdir() for the same
+ * directory handle. In this case, readdir() should skip over entries
+ * coming before the position defined by the off_t value. If entries
+ * are added or removed while the directory handle is open, they filesystem
+ * may still include the entries that have been removed, and may not
+ * report the entries that have been created. However, addition or
+ * removal of entries must never cause readdir() to skip over unrelated
+ * entries or to report them more than once. This means
+ * that off_t can not be a simple index that enumerates the entries
+ * that have been returned but must contain sufficient information to
+ * uniquely determine the next directory entry to return even when the
+ * set of entries is changing.
+ *
+ * The function does not have to report the '.' and '..'
+ * entries, but is allowed to do so. Note that, if readdir does
+ * not return '.' or '..', they will not be implicitly returned,
+ * and this behavior is observable by the caller.
+ *
+ * Valid replies:
+ * fuse_reply_buf
+ * fuse_reply_data
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param size maximum number of bytes to send
+ * @param off offset to continue reading the directory stream
+ * @param fi file information
+ */
+ void (*readdir) (fuse_req_t req, fuse_ino_t ino, size_t size, off_t off,
+ struct fuse_file_info *fi);
+
+ /**
+ * Release an open directory
+ *
+ * For every opendir call there will be exactly one releasedir
+ * call (unless the filesystem is force-unmounted).
+ *
+ * fi->fh will contain the value set by the opendir method, or
+ * will be undefined if the opendir method didn't set any value.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ */
+ void (*releasedir) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi);
+
+ /**
+ * Synchronize directory contents
+ *
+ * If the datasync parameter is non-zero, then only the directory
+ * contents should be flushed, not the meta data.
+ *
+ * fi->fh will contain the value set by the opendir method, or
+ * will be undefined if the opendir method didn't set any value.
+ *
+ * If this request is answered with an error code of ENOSYS,
+ * this is treated as success and future calls to fsyncdir() will
+ * succeed automatically without being send to the filesystem
+ * process.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param datasync flag indicating if only data should be flushed
+ * @param fi file information
+ */
+ void (*fsyncdir) (fuse_req_t req, fuse_ino_t ino, int datasync,
+ struct fuse_file_info *fi);
+
+ /**
+ * Get file system statistics
+ *
+ * Valid replies:
+ * fuse_reply_statfs
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number, zero means "undefined"
+ */
+ void (*statfs) (fuse_req_t req, fuse_ino_t ino);
+
+ /**
+ * Set an extended attribute
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure with error code EOPNOTSUPP, i.e. all
+ * future setxattr() requests will fail with EOPNOTSUPP without being
+ * send to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ */
+ void (*setxattr) (fuse_req_t req, fuse_ino_t ino, const char *name,
+ const char *value, size_t size, int flags);
+
+ /**
+ * Get an extended attribute
+ *
+ * If size is zero, the size of the value should be sent with
+ * fuse_reply_xattr.
+ *
+ * If the size is non-zero, and the value fits in the buffer, the
+ * value should be sent with fuse_reply_buf.
+ *
+ * If the size is too small for the value, the ERANGE error should
+ * be sent.
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure with error code EOPNOTSUPP, i.e. all
+ * future getxattr() requests will fail with EOPNOTSUPP without being
+ * send to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_buf
+ * fuse_reply_data
+ * fuse_reply_xattr
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param name of the extended attribute
+ * @param size maximum size of the value to send
+ */
+ void (*getxattr) (fuse_req_t req, fuse_ino_t ino, const char *name,
+ size_t size);
+
+ /**
+ * List extended attribute names
+ *
+ * If size is zero, the total size of the attribute list should be
+ * sent with fuse_reply_xattr.
+ *
+ * If the size is non-zero, and the null character separated
+ * attribute list fits in the buffer, the list should be sent with
+ * fuse_reply_buf.
+ *
+ * If the size is too small for the list, the ERANGE error should
+ * be sent.
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure with error code EOPNOTSUPP, i.e. all
+ * future listxattr() requests will fail with EOPNOTSUPP without being
+ * send to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_buf
+ * fuse_reply_data
+ * fuse_reply_xattr
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param size maximum size of the list to send
+ */
+ void (*listxattr) (fuse_req_t req, fuse_ino_t ino, size_t size);
+
+ /**
+ * Remove an extended attribute
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure with error code EOPNOTSUPP, i.e. all
+ * future removexattr() requests will fail with EOPNOTSUPP without being
+ * send to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param name of the extended attribute
+ */
+ void (*removexattr) (fuse_req_t req, fuse_ino_t ino, const char *name);
+
+ /**
+ * Check file access permissions
+ *
+ * This will be called for the access() and chdir() system
+ * calls. If the 'default_permissions' mount option is given,
+ * this method is not called.
+ *
+ * This method is not called under Linux kernel versions 2.4.x
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent success, i.e. this and all future access()
+ * requests will succeed without being send to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param mask requested access mode
+ */
+ void (*access) (fuse_req_t req, fuse_ino_t ino, int mask);
+
+ /**
+ * Create and open a file
+ *
+ * If the file does not exist, first create it with the specified
+ * mode, and then open it.
+ *
+ * See the description of the open handler for more
+ * information.
+ *
+ * If this method is not implemented or under Linux kernel
+ * versions earlier than 2.6.15, the mknod() and open() methods
+ * will be called instead.
+ *
+ * If this request is answered with an error code of ENOSYS, the handler
+ * is treated as not implemented (i.e., for this and future requests the
+ * mknod() and open() handlers will be called instead).
+ *
+ * Valid replies:
+ * fuse_reply_create
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param parent inode number of the parent directory
+ * @param name to create
+ * @param mode file type and mode with which to create the new file
+ * @param fi file information
+ */
+ void (*create) (fuse_req_t req, fuse_ino_t parent, const char *name,
+ mode_t mode, struct fuse_file_info *fi);
+
+ /**
+ * Test for a POSIX file lock
+ *
+ * Valid replies:
+ * fuse_reply_lock
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ * @param lock the region/type to test
+ */
+ void (*getlk) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi, struct flock *lock);
+
+ /**
+ * Acquire, modify or release a POSIX file lock
+ *
+ * For POSIX threads (NPTL) there's a 1-1 relation between pid and
+ * owner, but otherwise this is not always the case. For checking
+ * lock ownership, 'fi->owner' must be used. The l_pid field in
+ * 'struct flock' should only be used to fill in this field in
+ * getlk().
+ *
+ * Note: if the locking methods are not implemented, the kernel
+ * will still allow file locking to work locally. Hence these are
+ * only interesting for network filesystems and similar.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ * @param lock the region/type to set
+ * @param sleep locking operation may sleep
+ */
+ void (*setlk) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi,
+ struct flock *lock, int sleep);
+
+ /**
+ * Map block index within file to block index within device
+ *
+ * Note: This makes sense only for block device backed filesystems
+ * mounted with the 'blkdev' option
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure, i.e. all future bmap() requests will
+ * fail with the same error code without being send to the filesystem
+ * process.
+ *
+ * Valid replies:
+ * fuse_reply_bmap
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param blocksize unit of block index
+ * @param idx block index within file
+ */
+ void (*bmap) (fuse_req_t req, fuse_ino_t ino, size_t blocksize,
+ uint64_t idx);
+
+ /**
+ * Ioctl
+ *
+ * Note: For unrestricted ioctls (not allowed for FUSE
+ * servers), data in and out areas can be discovered by giving
+ * iovs and setting FUSE_IOCTL_RETRY in *flags*. For
+ * restricted ioctls, kernel prepares in/out data area
+ * according to the information encoded in cmd.
+ *
+ * Valid replies:
+ * fuse_reply_ioctl_retry
+ * fuse_reply_ioctl
+ * fuse_reply_ioctl_iov
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param cmd ioctl command
+ * @param arg ioctl argument
+ * @param fi file information
+ * @param flags for FUSE_IOCTL_* flags
+ * @param in_buf data fetched from the caller
+ * @param in_bufsz number of fetched bytes
+ * @param out_bufsz maximum size of output data
+ *
+ * Note : the unsigned long request submitted by the application
+ * is truncated to 32 bits.
+ */
+ void (*ioctl) (fuse_req_t req, fuse_ino_t ino, unsigned int cmd,
+ void *arg, struct fuse_file_info *fi, unsigned flags,
+ const void *in_buf, size_t in_bufsz, size_t out_bufsz);
+
+ /**
+ * Poll for IO readiness
+ *
+ * Note: If ph is non-NULL, the client should notify
+ * when IO readiness events occur by calling
+ * fuse_lowlevel_notify_poll() with the specified ph.
+ *
+ * Regardless of the number of times poll with a non-NULL ph
+ * is received, single notification is enough to clear all.
+ * Notifying more times incurs overhead but doesn't harm
+ * correctness.
+ *
+ * The callee is responsible for destroying ph with
+ * fuse_pollhandle_destroy() when no longer in use.
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as success (with a kernel-defined default poll-mask) and
+ * future calls to pull() will succeed the same way without being send
+ * to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_poll
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ * @param ph poll handle to be used for notification
+ */
+ void (*poll) (fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi,
+ struct fuse_pollhandle *ph);
+
+ /**
+ * Write data made available in a buffer
+ *
+ * This is a more generic version of the ->write() method. If
+ * FUSE_CAP_SPLICE_READ is set in fuse_conn_info.want and the
+ * kernel supports splicing from the fuse device, then the
+ * data will be made available in pipe for supporting zero
+ * copy data transfer.
+ *
+ * buf->count is guaranteed to be one (and thus buf->idx is
+ * always zero). The write_buf handler must ensure that
+ * bufv->off is correctly updated (reflecting the number of
+ * bytes read from bufv->buf[0]).
+ *
+ * Unless FUSE_CAP_HANDLE_KILLPRIV is disabled, this method is
+ * expected to reset the setuid and setgid bits.
+ *
+ * Valid replies:
+ * fuse_reply_write
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param bufv buffer containing the data
+ * @param off offset to write to
+ * @param fi file information
+ */
+ void (*write_buf) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_bufvec *bufv, off_t off,
+ struct fuse_file_info *fi);
+
+ /**
+ * Callback function for the retrieve request
+ *
+ * Valid replies:
+ * fuse_reply_none
+ *
+ * @param req request handle
+ * @param cookie user data supplied to fuse_lowlevel_notify_retrieve()
+ * @param ino the inode number supplied to fuse_lowlevel_notify_retrieve()
+ * @param offset the offset supplied to fuse_lowlevel_notify_retrieve()
+ * @param bufv the buffer containing the returned data
+ */
+ void (*retrieve_reply) (fuse_req_t req, void *cookie, fuse_ino_t ino,
+ off_t offset, struct fuse_bufvec *bufv);
+
+ /**
+ * Forget about multiple inodes
+ *
+ * See description of the forget function for more
+ * information.
+ *
+ * Valid replies:
+ * fuse_reply_none
+ *
+ * @param req request handle
+ */
+ void (*forget_multi) (fuse_req_t req, size_t count,
+ struct fuse_forget_data *forgets);
+
+ /**
+ * Acquire, modify or release a BSD file lock
+ *
+ * Note: if the locking methods are not implemented, the kernel
+ * will still allow file locking to work locally. Hence these are
+ * only interesting for network filesystems and similar.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param fi file information
+ * @param op the locking operation, see flock(2)
+ */
+ void (*flock) (fuse_req_t req, fuse_ino_t ino,
+ struct fuse_file_info *fi, int op);
+
+ /**
+ * Allocate requested space. If this function returns success then
+ * subsequent writes to the specified range shall not fail due to the lack
+ * of free space on the file system storage media.
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure with error code EOPNOTSUPP, i.e. all
+ * future fallocate() requests will fail with EOPNOTSUPP without being
+ * send to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param offset starting point for allocated region
+ * @param length size of allocated region
+ * @param mode determines the operation to be performed on the given range,
+ * see fallocate(2)
+ */
+ void (*fallocate) (fuse_req_t req, fuse_ino_t ino, int mode,
+ off_t offset, off_t length, struct fuse_file_info *fi);
+
+ /**
+ * Read directory with attributes
+ *
+ * Send a buffer filled using fuse_add_direntry_plus(), with size not
+ * exceeding the requested size. Send an empty buffer on end of
+ * stream.
+ *
+ * fi->fh will contain the value set by the opendir method, or
+ * will be undefined if the opendir method didn't set any value.
+ *
+ * In contrast to readdir() (which does not affect the lookup counts),
+ * the lookup count of every entry returned by readdirplus(), except "."
+ * and "..", is incremented by one.
+ *
+ * Valid replies:
+ * fuse_reply_buf
+ * fuse_reply_data
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param size maximum number of bytes to send
+ * @param off offset to continue reading the directory stream
+ * @param fi file information
+ */
+ void (*readdirplus) (fuse_req_t req, fuse_ino_t ino, size_t size, off_t off,
+ struct fuse_file_info *fi);
+
+ /**
+ * Copy a range of data from one file to another
+ *
+ * Performs an optimized copy between two file descriptors without the
+ * additional cost of transferring data through the FUSE kernel module
+ * to user space (glibc) and then back into the FUSE filesystem again.
+ *
+ * In case this method is not implemented, glibc falls back to reading
+ * data from the source and writing to the destination. Effectively
+ * doing an inefficient copy of the data.
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure with error code EOPNOTSUPP, i.e. all
+ * future copy_file_range() requests will fail with EOPNOTSUPP without
+ * being send to the filesystem process.
+ *
+ * Valid replies:
+ * fuse_reply_write
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino_in the inode number or the source file
+ * @param off_in starting point from were the data should be read
+ * @param fi_in file information of the source file
+ * @param ino_out the inode number or the destination file
+ * @param off_out starting point where the data should be written
+ * @param fi_out file information of the destination file
+ * @param len maximum size of the data to copy
+ * @param flags passed along with the copy_file_range() syscall
+ */
+ void (*copy_file_range) (fuse_req_t req, fuse_ino_t ino_in,
+ off_t off_in, struct fuse_file_info *fi_in,
+ fuse_ino_t ino_out, off_t off_out,
+ struct fuse_file_info *fi_out, size_t len,
+ int flags);
+
+ /**
+ * Find next data or hole after the specified offset
+ *
+ * If this request is answered with an error code of ENOSYS, this is
+ * treated as a permanent failure, i.e. all future lseek() requests will
+ * fail with the same error code without being send to the filesystem
+ * process.
+ *
+ * Valid replies:
+ * fuse_reply_lseek
+ * fuse_reply_err
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param off offset to start search from
+ * @param whence either SEEK_DATA or SEEK_HOLE
+ * @param fi file information
+ */
+ void (*lseek) (fuse_req_t req, fuse_ino_t ino, off_t off, int whence,
+ struct fuse_file_info *fi);
+};
+
+/**
+ * Reply with an error code or success.
+ *
+ * Possible requests:
+ * all except forget
+ *
+ * Whereever possible, error codes should be chosen from the list of
+ * documented error conditions in the corresponding system calls
+ * manpage.
+ *
+ * An error code of ENOSYS is sometimes treated specially. This is
+ * indicated in the documentation of the affected handler functions.
+ *
+ * The following requests may be answered with a zero error code:
+ * unlink, rmdir, rename, flush, release, fsync, fsyncdir, setxattr,
+ * removexattr, setlk.
+ *
+ * @param req request handle
+ * @param err the positive error value, or zero for success
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_err(fuse_req_t req, int err);
+
+/**
+ * Don't send reply
+ *
+ * Possible requests:
+ * forget
+ * forget_multi
+ * retrieve_reply
+ *
+ * @param req request handle
+ */
+void fuse_reply_none(fuse_req_t req);
+
+/**
+ * Reply with a directory entry
+ *
+ * Possible requests:
+ * lookup, mknod, mkdir, symlink, link
+ *
+ * Side effects:
+ * increments the lookup count on success
+ *
+ * @param req request handle
+ * @param e the entry parameters
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_entry(fuse_req_t req, const struct fuse_entry_param *e);
+
+/**
+ * Reply with a directory entry and open parameters
+ *
+ * currently the following members of 'fi' are used:
+ * fh, direct_io, keep_cache
+ *
+ * Possible requests:
+ * create
+ *
+ * Side effects:
+ * increments the lookup count on success
+ *
+ * @param req request handle
+ * @param e the entry parameters
+ * @param fi file information
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_create(fuse_req_t req, const struct fuse_entry_param *e,
+ const struct fuse_file_info *fi);
+
+/**
+ * Reply with attributes
+ *
+ * Possible requests:
+ * getattr, setattr
+ *
+ * @param req request handle
+ * @param attr the attributes
+ * @param attr_timeout validity timeout (in seconds) for the attributes
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_attr(fuse_req_t req, const struct stat *attr,
+ double attr_timeout);
+
+/**
+ * Reply with the contents of a symbolic link
+ *
+ * Possible requests:
+ * readlink
+ *
+ * @param req request handle
+ * @param link symbolic link contents
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_readlink(fuse_req_t req, const char *link);
+
+/**
+ * Reply with open parameters
+ *
+ * currently the following members of 'fi' are used:
+ * fh, direct_io, keep_cache
+ *
+ * Possible requests:
+ * open, opendir
+ *
+ * @param req request handle
+ * @param fi file information
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_open(fuse_req_t req, const struct fuse_file_info *fi);
+
+/**
+ * Reply with number of bytes written
+ *
+ * Possible requests:
+ * write
+ *
+ * @param req request handle
+ * @param count the number of bytes written
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_write(fuse_req_t req, size_t count);
+
+/**
+ * Reply with data
+ *
+ * Possible requests:
+ * read, readdir, getxattr, listxattr
+ *
+ * @param req request handle
+ * @param buf buffer containing data
+ * @param size the size of data in bytes
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_buf(fuse_req_t req, const char *buf, size_t size);
+
+/**
+ * Reply with data copied/moved from buffer(s)
+ *
+ * Zero copy data transfer ("splicing") will be used under
+ * the following circumstances:
+ *
+ * 1. FUSE_CAP_SPLICE_WRITE is set in fuse_conn_info.want, and
+ * 2. the kernel supports splicing from the fuse device
+ * (FUSE_CAP_SPLICE_WRITE is set in fuse_conn_info.capable), and
+ * 3. *flags* does not contain FUSE_BUF_NO_SPLICE
+ * 4. The amount of data that is provided in file-descriptor backed
+ * buffers (i.e., buffers for which bufv[n].flags == FUSE_BUF_FD)
+ * is at least twice the page size.
+ *
+ * In order for SPLICE_F_MOVE to be used, the following additional
+ * conditions have to be fulfilled:
+ *
+ * 1. FUSE_CAP_SPLICE_MOVE is set in fuse_conn_info.want, and
+ * 2. the kernel supports it (i.e, FUSE_CAP_SPLICE_MOVE is set in
+ fuse_conn_info.capable), and
+ * 3. *flags* contains FUSE_BUF_SPLICE_MOVE
+ *
+ * Note that, if splice is used, the data is actually spliced twice:
+ * once into a temporary pipe (to prepend header data), and then again
+ * into the kernel. If some of the provided buffers are memory-backed,
+ * the data in them is copied in step one and spliced in step two.
+ *
+ * The FUSE_BUF_SPLICE_FORCE_SPLICE and FUSE_BUF_SPLICE_NONBLOCK flags
+ * are silently ignored.
+ *
+ * Possible requests:
+ * read, readdir, getxattr, listxattr
+ *
+ * Side effects:
+ * when used to return data from a readdirplus() (but not readdir())
+ * call, increments the lookup count of each returned entry by one
+ * on success.
+ *
+ * @param req request handle
+ * @param bufv buffer vector
+ * @param flags flags controlling the copy
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_data(fuse_req_t req, struct fuse_bufvec *bufv,
+ enum fuse_buf_copy_flags flags);
+
+/**
+ * Reply with data vector
+ *
+ * Possible requests:
+ * read, readdir, getxattr, listxattr
+ *
+ * @param req request handle
+ * @param iov the vector containing the data
+ * @param count the size of vector
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_iov(fuse_req_t req, const struct iovec *iov, int count);
+
+/**
+ * Reply with filesystem statistics
+ *
+ * Possible requests:
+ * statfs
+ *
+ * @param req request handle
+ * @param stbuf filesystem statistics
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_statfs(fuse_req_t req, const struct statvfs *stbuf);
+
+/**
+ * Reply with needed buffer size
+ *
+ * Possible requests:
+ * getxattr, listxattr
+ *
+ * @param req request handle
+ * @param count the buffer size needed in bytes
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_xattr(fuse_req_t req, size_t count);
+
+/**
+ * Reply with file lock information
+ *
+ * Possible requests:
+ * getlk
+ *
+ * @param req request handle
+ * @param lock the lock information
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_lock(fuse_req_t req, const struct flock *lock);
+
+/**
+ * Reply with block index
+ *
+ * Possible requests:
+ * bmap
+ *
+ * @param req request handle
+ * @param idx block index within device
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_bmap(fuse_req_t req, uint64_t idx);
+
+/* ----------------------------------------------------------- *
+ * Filling a buffer in readdir *
+ * ----------------------------------------------------------- */
+
+/**
+ * Add a directory entry to the buffer
+ *
+ * Buffer needs to be large enough to hold the entry. If it's not,
+ * then the entry is not filled in but the size of the entry is still
+ * returned. The caller can check this by comparing the bufsize
+ * parameter with the returned entry size. If the entry size is
+ * larger than the buffer size, the operation failed.
+ *
+ * From the 'stbuf' argument the st_ino field and bits 12-15 of the
+ * st_mode field are used. The other fields are ignored.
+ *
+ * *off* should be any non-zero value that the filesystem can use to
+ * identify the current point in the directory stream. It does not
+ * need to be the actual physical position. A value of zero is
+ * reserved to mean "from the beginning", and should therefore never
+ * be used (the first call to fuse_add_direntry should be passed the
+ * offset of the second directory entry).
+ *
+ * @param req request handle
+ * @param buf the point where the new entry will be added to the buffer
+ * @param bufsize remaining size of the buffer
+ * @param name the name of the entry
+ * @param stbuf the file attributes
+ * @param off the offset of the next entry
+ * @return the space needed for the entry
+ */
+size_t fuse_add_direntry(fuse_req_t req, char *buf, size_t bufsize,
+ const char *name, const struct stat *stbuf,
+ off_t off);
+
+/**
+ * Add a directory entry to the buffer with the attributes
+ *
+ * See documentation of `fuse_add_direntry()` for more details.
+ *
+ * @param req request handle
+ * @param buf the point where the new entry will be added to the buffer
+ * @param bufsize remaining size of the buffer
+ * @param name the name of the entry
+ * @param e the directory entry
+ * @param off the offset of the next entry
+ * @return the space needed for the entry
+ */
+size_t fuse_add_direntry_plus(fuse_req_t req, char *buf, size_t bufsize,
+ const char *name,
+ const struct fuse_entry_param *e, off_t off);
+
+/**
+ * Reply to ask for data fetch and output buffer preparation. ioctl
+ * will be retried with the specified input data fetched and output
+ * buffer prepared.
+ *
+ * Possible requests:
+ * ioctl
+ *
+ * @param req request handle
+ * @param in_iov iovec specifying data to fetch from the caller
+ * @param in_count number of entries in in_iov
+ * @param out_iov iovec specifying addresses to write output to
+ * @param out_count number of entries in out_iov
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_ioctl_retry(fuse_req_t req,
+ const struct iovec *in_iov, size_t in_count,
+ const struct iovec *out_iov, size_t out_count);
+
+/**
+ * Reply to finish ioctl
+ *
+ * Possible requests:
+ * ioctl
+ *
+ * @param req request handle
+ * @param result result to be passed to the caller
+ * @param buf buffer containing output data
+ * @param size length of output data
+ */
+int fuse_reply_ioctl(fuse_req_t req, int result, const void *buf, size_t size);
+
+/**
+ * Reply to finish ioctl with iov buffer
+ *
+ * Possible requests:
+ * ioctl
+ *
+ * @param req request handle
+ * @param result result to be passed to the caller
+ * @param iov the vector containing the data
+ * @param count the size of vector
+ */
+int fuse_reply_ioctl_iov(fuse_req_t req, int result, const struct iovec *iov,
+ int count);
+
+/**
+ * Reply with poll result event mask
+ *
+ * @param req request handle
+ * @param revents poll result event mask
+ */
+int fuse_reply_poll(fuse_req_t req, unsigned revents);
+
+/**
+ * Reply with offset
+ *
+ * Possible requests:
+ * lseek
+ *
+ * @param req request handle
+ * @param off offset of next data or hole
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_lseek(fuse_req_t req, off_t off);
+
+/* ----------------------------------------------------------- *
+ * Notification *
+ * ----------------------------------------------------------- */
+
+/**
+ * Notify IO readiness event
+ *
+ * For more information, please read comment for poll operation.
+ *
+ * @param ph poll handle to notify IO readiness event for
+ */
+int fuse_lowlevel_notify_poll(struct fuse_pollhandle *ph);
+
+/**
+ * Notify to invalidate cache for an inode.
+ *
+ * Added in FUSE protocol version 7.12. If the kernel does not support
+ * this (or a newer) version, the function will return -ENOSYS and do
+ * nothing.
+ *
+ * If the filesystem has writeback caching enabled, invalidating an
+ * inode will first trigger a writeback of all dirty pages. The call
+ * will block until all writeback requests have completed and the
+ * inode has been invalidated. It will, however, not wait for
+ * completion of pending writeback requests that have been issued
+ * before.
+ *
+ * If there are no dirty pages, this function will never block.
+ *
+ * @param se the session object
+ * @param ino the inode number
+ * @param off the offset in the inode where to start invalidating
+ * or negative to invalidate attributes only
+ * @param len the amount of cache to invalidate or 0 for all
+ * @return zero for success, -errno for failure
+ */
+int fuse_lowlevel_notify_inval_inode(struct fuse_session *se, fuse_ino_t ino,
+ off_t off, off_t len);
+
+/**
+ * Notify to invalidate parent attributes and the dentry matching
+ * parent/name
+ *
+ * To avoid a deadlock this function must not be called in the
+ * execution path of a related filesytem operation or within any code
+ * that could hold a lock that could be needed to execute such an
+ * operation. As of kernel 4.18, a "related operation" is a lookup(),
+ * symlink(), mknod(), mkdir(), unlink(), rename(), link() or create()
+ * request for the parent, and a setattr(), unlink(), rmdir(),
+ * rename(), setxattr(), removexattr(), readdir() or readdirplus()
+ * request for the inode itself.
+ *
+ * When called correctly, this function will never block.
+ *
+ * Added in FUSE protocol version 7.12. If the kernel does not support
+ * this (or a newer) version, the function will return -ENOSYS and do
+ * nothing.
+ *
+ * @param se the session object
+ * @param parent inode number
+ * @param name file name
+ * @param namelen strlen() of file name
+ * @return zero for success, -errno for failure
+ */
+int fuse_lowlevel_notify_inval_entry(struct fuse_session *se, fuse_ino_t parent,
+ const char *name, size_t namelen);
+
+/**
+ * This function behaves like fuse_lowlevel_notify_inval_entry() with
+ * the following additional effect (at least as of Linux kernel 4.8):
+ *
+ * If the provided *child* inode matches the inode that is currently
+ * associated with the cached dentry, and if there are any inotify
+ * watches registered for the dentry, then the watchers are informed
+ * that the dentry has been deleted.
+ *
+ * To avoid a deadlock this function must not be called while
+ * executing a related filesytem operation or while holding a lock
+ * that could be needed to execute such an operation (see the
+ * description of fuse_lowlevel_notify_inval_entry() for more
+ * details).
+ *
+ * When called correctly, this function will never block.
+ *
+ * Added in FUSE protocol version 7.18. If the kernel does not support
+ * this (or a newer) version, the function will return -ENOSYS and do
+ * nothing.
+ *
+ * @param se the session object
+ * @param parent inode number
+ * @param child inode number
+ * @param name file name
+ * @param namelen strlen() of file name
+ * @return zero for success, -errno for failure
+ */
+int fuse_lowlevel_notify_delete(struct fuse_session *se,
+ fuse_ino_t parent, fuse_ino_t child,
+ const char *name, size_t namelen);
+
+/**
+ * Store data to the kernel buffers
+ *
+ * Synchronously store data in the kernel buffers belonging to the
+ * given inode. The stored data is marked up-to-date (no read will be
+ * performed against it, unless it's invalidated or evicted from the
+ * cache).
+ *
+ * If the stored data overflows the current file size, then the size
+ * is extended, similarly to a write(2) on the filesystem.
+ *
+ * If this function returns an error, then the store wasn't fully
+ * completed, but it may have been partially completed.
+ *
+ * Added in FUSE protocol version 7.15. If the kernel does not support
+ * this (or a newer) version, the function will return -ENOSYS and do
+ * nothing.
+ *
+ * @param se the session object
+ * @param ino the inode number
+ * @param offset the starting offset into the file to store to
+ * @param bufv buffer vector
+ * @param flags flags controlling the copy
+ * @return zero for success, -errno for failure
+ */
+int fuse_lowlevel_notify_store(struct fuse_session *se, fuse_ino_t ino,
+ off_t offset, struct fuse_bufvec *bufv,
+ enum fuse_buf_copy_flags flags);
+/**
+ * Retrieve data from the kernel buffers
+ *
+ * Retrieve data in the kernel buffers belonging to the given inode.
+ * If successful then the retrieve_reply() method will be called with
+ * the returned data.
+ *
+ * Only present pages are returned in the retrieve reply. Retrieving
+ * stops when it finds a non-present page and only data prior to that
+ * is returned.
+ *
+ * If this function returns an error, then the retrieve will not be
+ * completed and no reply will be sent.
+ *
+ * This function doesn't change the dirty state of pages in the kernel
+ * buffer. For dirty pages the write() method will be called
+ * regardless of having been retrieved previously.
+ *
+ * Added in FUSE protocol version 7.15. If the kernel does not support
+ * this (or a newer) version, the function will return -ENOSYS and do
+ * nothing.
+ *
+ * @param se the session object
+ * @param ino the inode number
+ * @param size the number of bytes to retrieve
+ * @param offset the starting offset into the file to retrieve from
+ * @param cookie user data to supply to the reply callback
+ * @return zero for success, -errno for failure
+ */
+int fuse_lowlevel_notify_retrieve(struct fuse_session *se, fuse_ino_t ino,
+ size_t size, off_t offset, void *cookie);
+
+
+/* ----------------------------------------------------------- *
+ * Utility functions *
+ * ----------------------------------------------------------- */
+
+/**
+ * Get the userdata from the request
+ *
+ * @param req request handle
+ * @return the user data passed to fuse_session_new()
+ */
+void *fuse_req_userdata(fuse_req_t req);
+
+/**
+ * Get the context from the request
+ *
+ * The pointer returned by this function will only be valid for the
+ * request's lifetime
+ *
+ * @param req request handle
+ * @return the context structure
+ */
+const struct fuse_ctx *fuse_req_ctx(fuse_req_t req);
+
+/**
+ * Get the current supplementary group IDs for the specified request
+ *
+ * Similar to the getgroups(2) system call, except the return value is
+ * always the total number of group IDs, even if it is larger than the
+ * specified size.
+ *
+ * The current fuse kernel module in linux (as of 2.6.30) doesn't pass
+ * the group list to userspace, hence this function needs to parse
+ * "/proc/$TID/task/$TID/status" to get the group IDs.
+ *
+ * This feature may not be supported on all operating systems. In
+ * such a case this function will return -ENOSYS.
+ *
+ * @param req request handle
+ * @param size size of given array
+ * @param list array of group IDs to be filled in
+ * @return the total number of supplementary group IDs or -errno on failure
+ */
+int fuse_req_getgroups(fuse_req_t req, int size, gid_t list[]);
+
+/**
+ * Callback function for an interrupt
+ *
+ * @param req interrupted request
+ * @param data user data
+ */
+typedef void (*fuse_interrupt_func_t)(fuse_req_t req, void *data);
+
+/**
+ * Register/unregister callback for an interrupt
+ *
+ * If an interrupt has already happened, then the callback function is
+ * called from within this function, hence it's not possible for
+ * interrupts to be lost.
+ *
+ * @param req request handle
+ * @param func the callback function or NULL for unregister
+ * @param data user data passed to the callback function
+ */
+void fuse_req_interrupt_func(fuse_req_t req, fuse_interrupt_func_t func,
+ void *data);
+
+/**
+ * Check if a request has already been interrupted
+ *
+ * @param req request handle
+ * @return 1 if the request has been interrupted, 0 otherwise
+ */
+int fuse_req_interrupted(fuse_req_t req);
+
+
+/* ----------------------------------------------------------- *
+ * Inquiry functions *
+ * ----------------------------------------------------------- */
+
+/**
+ * Print low-level version information to stdout.
+ */
+void fuse_lowlevel_version(void);
+
+/**
+ * Print available low-level options to stdout. This is not an
+ * exhaustive list, but includes only those options that may be of
+ * interest to an end-user of a file system.
+ */
+void fuse_lowlevel_help(void);
+
+/**
+ * Print available options for `fuse_parse_cmdline()`.
+ */
+void fuse_cmdline_help(void);
+
+/* ----------------------------------------------------------- *
+ * Filesystem setup & teardown *
+ * ----------------------------------------------------------- */
+
+struct fuse_cmdline_opts {
+ int singlethread;
+ int foreground;
+ int debug;
+ int nodefault_subtype;
+ char *mountpoint;
+ int show_version;
+ int show_help;
+ int clone_fd;
+ unsigned int max_idle_threads;
+};
+
+/**
+ * Utility function to parse common options for simple file systems
+ * using the low-level API. A help text that describes the available
+ * options can be printed with `fuse_cmdline_help`. A single
+ * non-option argument is treated as the mountpoint. Multiple
+ * non-option arguments will result in an error.
+ *
+ * If neither -o subtype= or -o fsname= options are given, a new
+ * subtype option will be added and set to the basename of the program
+ * (the fsname will remain unset, and then defaults to "fuse").
+ *
+ * Known options will be removed from *args*, unknown options will
+ * remain.
+ *
+ * @param args argument vector (input+output)
+ * @param opts output argument for parsed options
+ * @return 0 on success, -1 on failure
+ */
+int fuse_parse_cmdline(struct fuse_args *args,
+ struct fuse_cmdline_opts *opts);
+
+/**
+ * Create a low level session.
+ *
+ * Returns a session structure suitable for passing to
+ * fuse_session_mount() and fuse_session_loop().
+ *
+ * This function accepts most file-system independent mount options
+ * (like context, nodev, ro - see mount(8)), as well as the general
+ * fuse mount options listed in mount.fuse(8) (e.g. -o allow_root and
+ * -o default_permissions, but not ``-o use_ino``). Instead of `-o
+ * debug`, debugging may also enabled with `-d` or `--debug`.
+ *
+ * If not all options are known, an error message is written to stderr
+ * and the function returns NULL.
+ *
+ * Option parsing skips argv[0], which is assumed to contain the
+ * program name. To prevent accidentally passing an option in
+ * argv[0], this element must always be present (even if no options
+ * are specified). It may be set to the empty string ('\0') if no
+ * reasonable value can be provided.
+ *
+ * @param args argument vector
+ * @param op the (low-level) filesystem operations
+ * @param op_size sizeof(struct fuse_lowlevel_ops)
+ * @param userdata user data
+ *
+ * @return the fuse session on success, NULL on failure
+ **/
+struct fuse_session *fuse_session_new(struct fuse_args *args,
+ const struct fuse_lowlevel_ops *op,
+ size_t op_size, void *userdata);
+
+/**
+ * Mount a FUSE file system.
+ *
+ * @param mountpoint the mount point path
+ * @param se session object
+ *
+ * @return 0 on success, -1 on failure.
+ **/
+int fuse_session_mount(struct fuse_session *se, const char *mountpoint);
+
+/**
+ * Enter a single threaded, blocking event loop.
+ *
+ * When the event loop terminates because the connection to the FUSE
+ * kernel module has been closed, this function returns zero. This
+ * happens when the filesystem is unmounted regularly (by the
+ * filesystem owner or root running the umount(8) or fusermount(1)
+ * command), or if connection is explicitly severed by writing ``1``
+ * to the``abort`` file in ``/sys/fs/fuse/connections/NNN``. The only
+ * way to distinguish between these two conditions is to check if the
+ * filesystem is still mounted after the session loop returns.
+ *
+ * When some error occurs during request processing, the function
+ * returns a negated errno(3) value.
+ *
+ * If the loop has been terminated because of a signal handler
+ * installed by fuse_set_signal_handlers(), this function returns the
+ * (positive) signal value that triggered the exit.
+ *
+ * @param se the session
+ * @return 0, -errno, or a signal value
+ */
+int fuse_session_loop(struct fuse_session *se);
+
+/**
+ * Enter a multi-threaded event loop.
+ *
+ * For a description of the return value and the conditions when the
+ * event loop exits, refer to the documentation of
+ * fuse_session_loop().
+ *
+ * @param se the session
+ * @param config session loop configuration
+ * @return see fuse_session_loop()
+ */
+#if FUSE_USE_VERSION < 32
+int fuse_session_loop_mt_31(struct fuse_session *se, int clone_fd);
+#define fuse_session_loop_mt(se, clone_fd) fuse_session_loop_mt_31(se, clone_fd)
+#else
+int fuse_session_loop_mt(struct fuse_session *se, struct fuse_loop_config *config);
+#endif
+
+/**
+ * Flag a session as terminated.
+ *
+ * This function is invoked by the POSIX signal handlers, when
+ * registered using fuse_set_signal_handlers(). It will cause any
+ * running event loops to terminate on the next opportunity.
+ *
+ * @param se the session
+ */
+void fuse_session_exit(struct fuse_session *se);
+
+/**
+ * Reset the terminated flag of a session
+ *
+ * @param se the session
+ */
+void fuse_session_reset(struct fuse_session *se);
+
+/**
+ * Query the terminated flag of a session
+ *
+ * @param se the session
+ * @return 1 if exited, 0 if not exited
+ */
+int fuse_session_exited(struct fuse_session *se);
+
+/**
+ * Ensure that file system is unmounted.
+ *
+ * In regular operation, the file system is typically unmounted by the
+ * user calling umount(8) or fusermount(1), which then terminates the
+ * FUSE session loop. However, the session loop may also terminate as
+ * a result of an explicit call to fuse_session_exit() (e.g. by a
+ * signal handler installed by fuse_set_signal_handler()). In this
+ * case the filesystem remains mounted, but any attempt to access it
+ * will block (while the filesystem process is still running) or give
+ * an ESHUTDOWN error (after the filesystem process has terminated).
+ *
+ * If the communication channel with the FUSE kernel module is still
+ * open (i.e., if the session loop was terminated by an explicit call
+ * to fuse_session_exit()), this function will close it and unmount
+ * the filesystem. If the communication channel has been closed by the
+ * kernel, this method will do (almost) nothing.
+ *
+ * NOTE: The above semantics mean that if the connection to the kernel
+ * is terminated via the ``/sys/fs/fuse/connections/NNN/abort`` file,
+ * this method will *not* unmount the filesystem.
+ *
+ * @param se the session
+ */
+void fuse_session_unmount(struct fuse_session *se);
+
+/**
+ * Destroy a session
+ *
+ * @param se the session
+ */
+void fuse_session_destroy(struct fuse_session *se);
+
+/* ----------------------------------------------------------- *
+ * Custom event loop support *
+ * ----------------------------------------------------------- */
+
+/**
+ * Return file descriptor for communication with kernel.
+ *
+ * The file selector can be used to integrate FUSE with a custom event
+ * loop. Whenever data is available for reading on the provided fd,
+ * the event loop should call `fuse_session_receive_buf` followed by
+ * `fuse_session_process_buf` to process the request.
+ *
+ * The returned file descriptor is valid until `fuse_session_unmount`
+ * is called.
+ *
+ * @param se the session
+ * @return a file descriptor
+ */
+int fuse_session_fd(struct fuse_session *se);
+
+/**
+ * Process a raw request supplied in a generic buffer
+ *
+ * The fuse_buf may contain a memory buffer or a pipe file descriptor.
+ *
+ * @param se the session
+ * @param buf the fuse_buf containing the request
+ */
+void fuse_session_process_buf(struct fuse_session *se,
+ const struct fuse_buf *buf);
+
+/**
+ * Read a raw request from the kernel into the supplied buffer.
+ *
+ * Depending on file system options, system capabilities, and request
+ * size the request is either read into a memory buffer or spliced
+ * into a temporary pipe.
+ *
+ * @param se the session
+ * @param buf the fuse_buf to store the request in
+ * @return the actual size of the raw request, or -errno on error
+ */
+int fuse_session_receive_buf(struct fuse_session *se, struct fuse_buf *buf);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* FUSE_LOWLEVEL_H_ */
diff --git a/tools/virtiofsd/fuse_misc.h b/tools/virtiofsd/fuse_misc.h
new file mode 100644
index 0000000000..2f6663ed7d
--- /dev/null
+++ b/tools/virtiofsd/fuse_misc.h
@@ -0,0 +1,59 @@
+/*
+ FUSE: Filesystem in Userspace
+ Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
+
+ This program can be distributed under the terms of the GNU LGPLv2.
+ See the file COPYING.LIB
+*/
+
+#include <pthread.h>
+
+/*
+ Versioned symbols cannot be used in some cases because it
+ - confuse the dynamic linker in uClibc
+ - not supported on MacOSX (in MachO binary format)
+*/
+#if (!defined(__UCLIBC__) && !defined(__APPLE__))
+#define FUSE_SYMVER(x) __asm__(x)
+#else
+#define FUSE_SYMVER(x)
+#endif
+
+#ifndef USE_UCLIBC
+#define fuse_mutex_init(mut) pthread_mutex_init(mut, NULL)
+#else
+/* Is this hack still needed? */
+static inline void fuse_mutex_init(pthread_mutex_t *mut)
+{
+ pthread_mutexattr_t attr;
+ pthread_mutexattr_init(&attr);
+ pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ADAPTIVE_NP);
+ pthread_mutex_init(mut, &attr);
+ pthread_mutexattr_destroy(&attr);
+}
+#endif
+
+#ifdef HAVE_STRUCT_STAT_ST_ATIM
+/* Linux */
+#define ST_ATIM_NSEC(stbuf) ((stbuf)->st_atim.tv_nsec)
+#define ST_CTIM_NSEC(stbuf) ((stbuf)->st_ctim.tv_nsec)
+#define ST_MTIM_NSEC(stbuf) ((stbuf)->st_mtim.tv_nsec)
+#define ST_ATIM_NSEC_SET(stbuf, val) (stbuf)->st_atim.tv_nsec = (val)
+#define ST_CTIM_NSEC_SET(stbuf, val) (stbuf)->st_ctim.tv_nsec = (val)
+#define ST_MTIM_NSEC_SET(stbuf, val) (stbuf)->st_mtim.tv_nsec = (val)
+#elif defined(HAVE_STRUCT_STAT_ST_ATIMESPEC)
+/* FreeBSD */
+#define ST_ATIM_NSEC(stbuf) ((stbuf)->st_atimespec.tv_nsec)
+#define ST_CTIM_NSEC(stbuf) ((stbuf)->st_ctimespec.tv_nsec)
+#define ST_MTIM_NSEC(stbuf) ((stbuf)->st_mtimespec.tv_nsec)
+#define ST_ATIM_NSEC_SET(stbuf, val) (stbuf)->st_atimespec.tv_nsec = (val)
+#define ST_CTIM_NSEC_SET(stbuf, val) (stbuf)->st_ctimespec.tv_nsec = (val)
+#define ST_MTIM_NSEC_SET(stbuf, val) (stbuf)->st_mtimespec.tv_nsec = (val)
+#else
+#define ST_ATIM_NSEC(stbuf) 0
+#define ST_CTIM_NSEC(stbuf) 0
+#define ST_MTIM_NSEC(stbuf) 0
+#define ST_ATIM_NSEC_SET(stbuf, val) do { } while (0)
+#define ST_CTIM_NSEC_SET(stbuf, val) do { } while (0)
+#define ST_MTIM_NSEC_SET(stbuf, val) do { } while (0)
+#endif
diff --git a/tools/virtiofsd/fuse_opt.h b/tools/virtiofsd/fuse_opt.h
new file mode 100644
index 0000000000..d8573e74fd
--- /dev/null
+++ b/tools/virtiofsd/fuse_opt.h
@@ -0,0 +1,271 @@
+/*
+ FUSE: Filesystem in Userspace
+ Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
+
+ This program can be distributed under the terms of the GNU LGPLv2.
+ See the file COPYING.LIB.
+*/
+
+#ifndef FUSE_OPT_H_
+#define FUSE_OPT_H_
+
+/** @file
+ *
+ * This file defines the option parsing interface of FUSE
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Option description
+ *
+ * This structure describes a single option, and action associated
+ * with it, in case it matches.
+ *
+ * More than one such match may occur, in which case the action for
+ * each match is executed.
+ *
+ * There are three possible actions in case of a match:
+ *
+ * i) An integer (int or unsigned) variable determined by 'offset' is
+ * set to 'value'
+ *
+ * ii) The processing function is called, with 'value' as the key
+ *
+ * iii) An integer (any) or string (char *) variable determined by
+ * 'offset' is set to the value of an option parameter
+ *
+ * 'offset' should normally be either set to
+ *
+ * - 'offsetof(struct foo, member)' actions i) and iii)
+ *
+ * - -1 action ii)
+ *
+ * The 'offsetof()' macro is defined in the <stddef.h> header.
+ *
+ * The template determines which options match, and also have an
+ * effect on the action. Normally the action is either i) or ii), but
+ * if a format is present in the template, then action iii) is
+ * performed.
+ *
+ * The types of templates are:
+ *
+ * 1) "-x", "-foo", "--foo", "--foo-bar", etc. These match only
+ * themselves. Invalid values are "--" and anything beginning
+ * with "-o"
+ *
+ * 2) "foo", "foo-bar", etc. These match "-ofoo", "-ofoo-bar" or
+ * the relevant option in a comma separated option list
+ *
+ * 3) "bar=", "--foo=", etc. These are variations of 1) and 2)
+ * which have a parameter
+ *
+ * 4) "bar=%s", "--foo=%lu", etc. Same matching as above but perform
+ * action iii).
+ *
+ * 5) "-x ", etc. Matches either "-xparam" or "-x param" as
+ * two separate arguments
+ *
+ * 6) "-x %s", etc. Combination of 4) and 5)
+ *
+ * If the format is "%s", memory is allocated for the string unlike with
+ * scanf(). The previous value (if non-NULL) stored at the this location is
+ * freed.
+ */
+struct fuse_opt {
+ /** Matching template and optional parameter formatting */
+ const char *templ;
+
+ /**
+ * Offset of variable within 'data' parameter of fuse_opt_parse()
+ * or -1
+ */
+ unsigned long offset;
+
+ /**
+ * Value to set the variable to, or to be passed as 'key' to the
+ * processing function. Ignored if template has a format
+ */
+ int value;
+};
+
+/**
+ * Key option. In case of a match, the processing function will be
+ * called with the specified key.
+ */
+#define FUSE_OPT_KEY(templ, key) { templ, -1U, key }
+
+/**
+ * Last option. An array of 'struct fuse_opt' must end with a NULL
+ * template value
+ */
+#define FUSE_OPT_END { NULL, 0, 0 }
+
+/**
+ * Argument list
+ */
+struct fuse_args {
+ /** Argument count */
+ int argc;
+
+ /** Argument vector. NULL terminated */
+ char **argv;
+
+ /** Is 'argv' allocated? */
+ int allocated;
+};
+
+/**
+ * Initializer for 'struct fuse_args'
+ */
+#define FUSE_ARGS_INIT(argc, argv) { argc, argv, 0 }
+
+/**
+ * Key value passed to the processing function if an option did not
+ * match any template
+ */
+#define FUSE_OPT_KEY_OPT -1
+
+/**
+ * Key value passed to the processing function for all non-options
+ *
+ * Non-options are the arguments beginning with a character other than
+ * '-' or all arguments after the special '--' option
+ */
+#define FUSE_OPT_KEY_NONOPT -2
+
+/**
+ * Special key value for options to keep
+ *
+ * Argument is not passed to processing function, but behave as if the
+ * processing function returned 1
+ */
+#define FUSE_OPT_KEY_KEEP -3
+
+/**
+ * Special key value for options to discard
+ *
+ * Argument is not passed to processing function, but behave as if the
+ * processing function returned zero
+ */
+#define FUSE_OPT_KEY_DISCARD -4
+
+/**
+ * Processing function
+ *
+ * This function is called if
+ * - option did not match any 'struct fuse_opt'
+ * - argument is a non-option
+ * - option did match and offset was set to -1
+ *
+ * The 'arg' parameter will always contain the whole argument or
+ * option including the parameter if exists. A two-argument option
+ * ("-x foo") is always converted to single argument option of the
+ * form "-xfoo" before this function is called.
+ *
+ * Options of the form '-ofoo' are passed to this function without the
+ * '-o' prefix.
+ *
+ * The return value of this function determines whether this argument
+ * is to be inserted into the output argument vector, or discarded.
+ *
+ * @param data is the user data passed to the fuse_opt_parse() function
+ * @param arg is the whole argument or option
+ * @param key determines why the processing function was called
+ * @param outargs the current output argument list
+ * @return -1 on error, 0 if arg is to be discarded, 1 if arg should be kept
+ */
+typedef int (*fuse_opt_proc_t)(void *data, const char *arg, int key,
+ struct fuse_args *outargs);
+
+/**
+ * Option parsing function
+ *
+ * If 'args' was returned from a previous call to fuse_opt_parse() or
+ * it was constructed from
+ *
+ * A NULL 'args' is equivalent to an empty argument vector
+ *
+ * A NULL 'opts' is equivalent to an 'opts' array containing a single
+ * end marker
+ *
+ * A NULL 'proc' is equivalent to a processing function always
+ * returning '1'
+ *
+ * @param args is the input and output argument list
+ * @param data is the user data
+ * @param opts is the option description array
+ * @param proc is the processing function
+ * @return -1 on error, 0 on success
+ */
+int fuse_opt_parse(struct fuse_args *args, void *data,
+ const struct fuse_opt opts[], fuse_opt_proc_t proc);
+
+/**
+ * Add an option to a comma separated option list
+ *
+ * @param opts is a pointer to an option list, may point to a NULL value
+ * @param opt is the option to add
+ * @return -1 on allocation error, 0 on success
+ */
+int fuse_opt_add_opt(char **opts, const char *opt);
+
+/**
+ * Add an option, escaping commas, to a comma separated option list
+ *
+ * @param opts is a pointer to an option list, may point to a NULL value
+ * @param opt is the option to add
+ * @return -1 on allocation error, 0 on success
+ */
+int fuse_opt_add_opt_escaped(char **opts, const char *opt);
+
+/**
+ * Add an argument to a NULL terminated argument vector
+ *
+ * @param args is the structure containing the current argument list
+ * @param arg is the new argument to add
+ * @return -1 on allocation error, 0 on success
+ */
+int fuse_opt_add_arg(struct fuse_args *args, const char *arg);
+
+/**
+ * Add an argument at the specified position in a NULL terminated
+ * argument vector
+ *
+ * Adds the argument to the N-th position. This is useful for adding
+ * options at the beginning of the array which must not come after the
+ * special '--' option.
+ *
+ * @param args is the structure containing the current argument list
+ * @param pos is the position at which to add the argument
+ * @param arg is the new argument to add
+ * @return -1 on allocation error, 0 on success
+ */
+int fuse_opt_insert_arg(struct fuse_args *args, int pos, const char *arg);
+
+/**
+ * Free the contents of argument list
+ *
+ * The structure itself is not freed
+ *
+ * @param args is the structure containing the argument list
+ */
+void fuse_opt_free_args(struct fuse_args *args);
+
+
+/**
+ * Check if an option matches
+ *
+ * @param opts is the option description array
+ * @param opt is the option to match
+ * @return 1 if a match is found, 0 if not
+ */
+int fuse_opt_match(const struct fuse_opt opts[], const char *opt);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* FUSE_OPT_H_ */
diff --git a/tools/virtiofsd/passthrough_helpers.h b/tools/virtiofsd/passthrough_helpers.h
new file mode 100644
index 0000000000..6b77c33600
--- /dev/null
+++ b/tools/virtiofsd/passthrough_helpers.h
@@ -0,0 +1,76 @@
+/*
+ * FUSE: Filesystem in Userspace
+ *
+ * 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 THE 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 THE 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
+ */
+
+/*
+ * Creates files on the underlying file system in response to a FUSE_MKNOD
+ * operation
+ */
+static int mknod_wrapper(int dirfd, const char *path, const char *link,
+ int mode, dev_t rdev)
+{
+ int res;
+
+ if (S_ISREG(mode)) {
+ res = openat(dirfd, path, O_CREAT | O_EXCL | O_WRONLY, mode);
+ if (res >= 0)
+ res = close(res);
+ } else if (S_ISDIR(mode)) {
+ res = mkdirat(dirfd, path, mode);
+ } else if (S_ISLNK(mode) && link != NULL) {
+ res = symlinkat(link, dirfd, path);
+ } else if (S_ISFIFO(mode)) {
+ res = mkfifoat(dirfd, path, mode);
+#ifdef __FreeBSD__
+ } else if (S_ISSOCK(mode)) {
+ struct sockaddr_un su;
+ int fd;
+
+ if (strlen(path) >= sizeof(su.sun_path)) {
+ errno = ENAMETOOLONG;
+ return -1;
+ }
+ fd = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (fd >= 0) {
+ /*
+ * We must bind the socket to the underlying file
+ * system to create the socket file, even though
+ * we'll never listen on this socket.
+ */
+ su.sun_family = AF_UNIX;
+ strncpy(su.sun_path, path, sizeof(su.sun_path));
+ res = bindat(dirfd, fd, (struct sockaddr*)&su,
+ sizeof(su));
+ if (res == 0)
+ close(fd);
+ } else {
+ res = -1;
+ }
+#endif
+ } else {
+ res = mknodat(dirfd, path, mode, rdev);
+ }
+
+ return res;
+}
--
2.23.0
next prev parent reply other threads:[~2019-12-12 16:48 UTC|newest]
Thread overview: 307+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-12 16:37 [PATCH 000/104] virtiofs daemon [all] Dr. David Alan Gilbert (git)
2019-12-12 16:37 ` Dr. David Alan Gilbert (git) [this message]
2020-01-03 11:54 ` [PATCH 001/104] virtiofsd: Pull in upstream headers Daniel P. Berrangé
2020-01-15 17:38 ` Philippe Mathieu-Daudé
2019-12-12 16:37 ` [PATCH 002/104] virtiofsd: Pull in kernel's fuse.h Dr. David Alan Gilbert (git)
2020-01-03 11:56 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 003/104] virtiofsd: Add auxiliary .c's Dr. David Alan Gilbert (git)
2020-01-03 11:57 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 004/104] virtiofsd: Add fuse_lowlevel.c Dr. David Alan Gilbert (git)
2020-01-03 11:58 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 005/104] virtiofsd: Add passthrough_ll Dr. David Alan Gilbert (git)
2020-01-03 12:01 ` Daniel P. Berrangé
2020-01-03 12:15 ` Dr. David Alan Gilbert
2020-01-03 12:33 ` Daniel P. Berrangé
2020-01-03 14:37 ` Dr. David Alan Gilbert
2019-12-12 16:37 ` [PATCH 006/104] virtiofsd: Trim down imported files Dr. David Alan Gilbert (git)
2020-01-03 12:02 ` Daniel P. Berrangé
2020-01-21 9:58 ` Xiao Yang
2020-01-21 10:51 ` Dr. David Alan Gilbert
2020-01-22 0:57 ` Xiao Yang
2019-12-12 16:37 ` [PATCH 007/104] virtiofsd: Format imported files to qemu style Dr. David Alan Gilbert (git)
2020-01-03 12:04 ` Daniel P. Berrangé
2020-01-09 12:21 ` Aleksandar Markovic
2019-12-12 16:37 ` [PATCH 008/104] virtiofsd: remove mountpoint dummy argument Dr. David Alan Gilbert (git)
2020-01-03 12:12 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 009/104] virtiofsd: remove unused notify reply support Dr. David Alan Gilbert (git)
2020-01-03 12:14 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 010/104] virtiofsd: Fix fuse_daemonize ignored return values Dr. David Alan Gilbert (git)
2020-01-03 12:18 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 011/104] virtiofsd: Fix common header and define for QEMU builds Dr. David Alan Gilbert (git)
2020-01-03 12:22 ` Daniel P. Berrangé
2020-01-06 16:29 ` Dr. David Alan Gilbert
2019-12-12 16:37 ` [PATCH 012/104] virtiofsd: Trim out compatibility code Dr. David Alan Gilbert (git)
2020-01-03 12:26 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 013/104] virtiofsd: Make fsync work even if only inode is passed in Dr. David Alan Gilbert (git)
2020-01-03 15:13 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 014/104] virtiofsd: Add options for virtio Dr. David Alan Gilbert (git)
2020-01-03 15:18 ` Daniel P. Berrangé
2020-01-10 16:01 ` Dr. David Alan Gilbert
2019-12-12 16:37 ` [PATCH 015/104] virtiofsd: add -o source=PATH to help output Dr. David Alan Gilbert (git)
2020-01-03 15:18 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 016/104] virtiofsd: Open vhost connection instead of mounting Dr. David Alan Gilbert (git)
2020-01-03 15:21 ` Daniel P. Berrangé
2020-01-21 6:57 ` Misono Tomohiro
2020-01-21 11:38 ` Dr. David Alan Gilbert
2019-12-12 16:37 ` [PATCH 017/104] virtiofsd: Start wiring up vhost-user Dr. David Alan Gilbert (git)
2020-01-03 15:25 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 018/104] virtiofsd: Add main virtio loop Dr. David Alan Gilbert (git)
2020-01-03 15:26 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 019/104] virtiofsd: get/set features callbacks Dr. David Alan Gilbert (git)
2020-01-03 15:26 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 020/104] virtiofsd: Start queue threads Dr. David Alan Gilbert (git)
2020-01-03 15:27 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 021/104] virtiofsd: Poll kick_fd for queue Dr. David Alan Gilbert (git)
2020-01-03 15:33 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 022/104] virtiofsd: Start reading commands from queue Dr. David Alan Gilbert (git)
2020-01-03 15:34 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 023/104] virtiofsd: Send replies to messages Dr. David Alan Gilbert (git)
2020-01-03 15:36 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 024/104] virtiofsd: Keep track of replies Dr. David Alan Gilbert (git)
2020-01-03 15:41 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 025/104] virtiofsd: Add Makefile wiring for virtiofsd contrib Dr. David Alan Gilbert (git)
2019-12-13 16:02 ` Liam Merwick
2019-12-13 16:56 ` Dr. David Alan Gilbert
2020-01-03 15:41 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 026/104] virtiofsd: Fast path for virtio read Dr. David Alan Gilbert (git)
2020-01-17 18:54 ` Masayoshi Mizuma
2020-01-20 12:32 ` Dr. David Alan Gilbert
2019-12-12 16:37 ` [PATCH 027/104] virtiofsd: add --fd=FDNUM fd passing option Dr. David Alan Gilbert (git)
2020-01-06 14:12 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 028/104] virtiofsd: make -f (foreground) the default Dr. David Alan Gilbert (git)
2020-01-06 14:19 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 029/104] virtiofsd: add vhost-user.json file Dr. David Alan Gilbert (git)
2020-01-06 14:19 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 030/104] virtiofsd: add --print-capabilities option Dr. David Alan Gilbert (git)
2020-01-06 14:20 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 031/104] virtiofs: Add maintainers entry Dr. David Alan Gilbert (git)
2020-01-06 14:21 ` Daniel P. Berrangé
2020-01-15 17:19 ` Philippe Mathieu-Daudé
2019-12-12 16:37 ` [PATCH 032/104] virtiofsd: passthrough_ll: create new files in caller's context Dr. David Alan Gilbert (git)
2020-01-06 14:30 ` Daniel P. Berrangé
2020-01-06 19:00 ` Dr. David Alan Gilbert
2020-01-06 19:08 ` Dr. David Alan Gilbert
2020-01-07 9:22 ` Daniel P. Berrangé
2020-01-10 13:05 ` Dr. David Alan Gilbert
2019-12-12 16:37 ` [PATCH 033/104] virtiofsd: passthrough_ll: add lo_map for ino/fh indirection Dr. David Alan Gilbert (git)
2020-01-17 21:44 ` Masayoshi Mizuma
2019-12-12 16:37 ` [PATCH 034/104] virtiofsd: passthrough_ll: add ino_map to hide lo_inode pointers Dr. David Alan Gilbert (git)
2020-01-17 21:45 ` Masayoshi Mizuma
2019-12-12 16:37 ` [PATCH 035/104] virtiofsd: passthrough_ll: add dirp_map to hide lo_dirp pointers Dr. David Alan Gilbert (git)
2020-01-17 13:58 ` Philippe Mathieu-Daudé
2019-12-12 16:37 ` [PATCH 036/104] virtiofsd: passthrough_ll: add fd_map to hide file descriptors Dr. David Alan Gilbert (git)
2020-01-17 22:32 ` Masayoshi Mizuma
2019-12-12 16:37 ` [PATCH 037/104] virtiofsd: passthrough_ll: add fallback for racy ops Dr. David Alan Gilbert (git)
2020-01-18 16:22 ` Masayoshi Mizuma
2020-01-20 13:26 ` Dr. David Alan Gilbert
2019-12-12 16:37 ` [PATCH 038/104] virtiofsd: validate path components Dr. David Alan Gilbert (git)
2020-01-06 14:32 ` Daniel P. Berrangé
2019-12-12 16:37 ` [PATCH 039/104] virtiofsd: Plumb fuse_bufvec through to do_write_buf Dr. David Alan Gilbert (git)
2020-01-17 21:01 ` Masayoshi Mizuma
2019-12-12 16:38 ` [PATCH 040/104] virtiofsd: Pass write iov's all the way through Dr. David Alan Gilbert (git)
2020-01-19 8:08 ` Xiao Yang
2020-01-20 8:24 ` Philippe Mathieu-Daudé
2020-01-20 13:28 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 041/104] virtiofsd: add fuse_mbuf_iter API Dr. David Alan Gilbert (git)
2020-01-16 14:17 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 042/104] virtiofsd: validate input buffer sizes in do_write_buf() Dr. David Alan Gilbert (git)
2020-01-16 14:19 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 043/104] virtiofsd: check input buffer size in fuse_lowlevel.c ops Dr. David Alan Gilbert (git)
2020-01-16 14:25 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 044/104] virtiofsd: prevent ".." escape in lo_do_lookup() Dr. David Alan Gilbert (git)
2020-01-16 14:33 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 045/104] virtiofsd: prevent ".." escape in lo_do_readdir() Dr. David Alan Gilbert (git)
2020-01-16 14:35 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 046/104] virtiofsd: use /proc/self/fd/ O_PATH file descriptor Dr. David Alan Gilbert (git)
2020-01-15 18:09 ` Philippe Mathieu-Daudé
2020-01-17 9:42 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 047/104] virtiofsd: sandbox mount namespace Dr. David Alan Gilbert (git)
2020-01-06 14:36 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 048/104] virtiofsd: move to an empty network namespace Dr. David Alan Gilbert (git)
2020-01-06 14:37 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 049/104] virtiofsd: move to a new pid namespace Dr. David Alan Gilbert (git)
2020-01-06 14:40 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 050/104] virtiofsd: add seccomp whitelist Dr. David Alan Gilbert (git)
2020-01-06 14:56 ` Daniel P. Berrangé
2020-01-06 18:54 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 051/104] virtiofsd: Parse flag FUSE_WRITE_KILL_PRIV Dr. David Alan Gilbert (git)
2020-01-15 12:06 ` Misono Tomohiro
2020-01-15 14:34 ` Dr. David Alan Gilbert
2020-01-16 14:37 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 052/104] virtiofsd: cap-ng helpers Dr. David Alan Gilbert (git)
2020-01-06 14:58 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 053/104] virtiofsd: Drop CAP_FSETID if client asked for it Dr. David Alan Gilbert (git)
2020-01-16 4:41 ` Misono Tomohiro
2020-01-16 15:21 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 054/104] virtiofsd: set maximum RLIMIT_NOFILE limit Dr. David Alan Gilbert (git)
2020-01-06 15:00 ` Daniel P. Berrangé
2020-01-15 17:09 ` Philippe Mathieu-Daudé
2020-01-15 17:38 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 055/104] virtiofsd: fix libfuse information leaks Dr. David Alan Gilbert (git)
2020-01-06 15:01 ` Daniel P. Berrangé
2020-01-15 17:07 ` Philippe Mathieu-Daudé
2019-12-12 16:38 ` [PATCH 056/104] virtiofsd: add security guide document Dr. David Alan Gilbert (git)
2020-01-06 15:03 ` Daniel P. Berrangé
2020-01-06 17:53 ` Dr. David Alan Gilbert
2020-01-07 10:05 ` Daniel P. Berrangé
2020-01-09 17:02 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 057/104] virtiofsd: add --syslog command-line option Dr. David Alan Gilbert (git)
2020-01-06 15:05 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 058/104] virtiofsd: print log only when priority is high enough Dr. David Alan Gilbert (git)
2020-01-06 15:10 ` Daniel P. Berrangé
2020-01-06 17:05 ` Dr. David Alan Gilbert
2020-01-06 17:20 ` Daniel P. Berrangé
2020-01-06 17:27 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 059/104] virtiofsd: Add ID to the log with FUSE_LOG_DEBUG level Dr. David Alan Gilbert (git)
2020-01-06 15:18 ` Daniel P. Berrangé
2020-01-06 17:47 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 060/104] virtiofsd: Add timestamp " Dr. David Alan Gilbert (git)
2020-01-07 11:11 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 061/104] virtiofsd: Handle reinit Dr. David Alan Gilbert (git)
2020-01-07 11:12 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 062/104] virtiofsd: Handle hard reboot Dr. David Alan Gilbert (git)
2020-01-07 11:14 ` Daniel P. Berrangé
2020-01-10 15:43 ` Dr. David Alan Gilbert
2020-01-20 6:46 ` Misono Tomohiro
2020-01-22 18:28 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 063/104] virtiofsd: Kill threads when queues are stopped Dr. David Alan Gilbert (git)
2020-01-07 11:16 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 064/104] vhost-user: Print unexpected slave message types Dr. David Alan Gilbert (git)
2020-01-07 11:18 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 065/104] contrib/libvhost-user: Protect slave fd with mutex Dr. David Alan Gilbert (git)
2020-01-07 11:19 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 066/104] virtiofsd: passthrough_ll: add renameat2 support Dr. David Alan Gilbert (git)
2020-01-07 11:21 ` Daniel P. Berrangé
2020-01-10 9:52 ` Dr. David Alan Gilbert
2020-01-13 20:06 ` Dr. David Alan Gilbert
2020-01-14 8:29 ` Daniel P. Berrangé
2020-01-14 10:07 ` Dr. David Alan Gilbert
2020-01-14 10:12 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 067/104] virtiofsd: passthrough_ll: disable readdirplus on cache=never Dr. David Alan Gilbert (git)
2020-01-07 11:22 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 068/104] virtiofsd: passthrough_ll: control readdirplus Dr. David Alan Gilbert (git)
2020-01-07 11:23 ` Daniel P. Berrangé
2020-01-10 15:04 ` Dr. David Alan Gilbert
2020-01-10 15:13 ` Miklos Szeredi
2020-01-10 15:18 ` Daniel P. Berrangé
2020-01-10 15:30 ` Miklos Szeredi
2020-01-10 15:40 ` Vivek Goyal
2020-01-10 16:00 ` Miklos Szeredi
2019-12-12 16:38 ` [PATCH 069/104] virtiofsd: rename unref_inode() to unref_inode_lolocked() Dr. David Alan Gilbert (git)
2020-01-07 11:23 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 070/104] virtiofsd: fail when parent inode isn't known in lo_do_lookup() Dr. David Alan Gilbert (git)
2020-01-16 7:17 ` Misono Tomohiro
2020-01-20 10:08 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 071/104] virtiofsd: extract root inode init into setup_root() Dr. David Alan Gilbert (git)
2020-01-16 7:20 ` Misono Tomohiro
2020-01-16 15:51 ` Dr. David Alan Gilbert
2020-01-20 10:09 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 072/104] virtiofsd: passthrough_ll: fix refcounting on remove/rename Dr. David Alan Gilbert (git)
2020-01-16 11:56 ` Misono Tomohiro
2020-01-16 16:45 ` Dr. David Alan Gilbert
2020-01-17 10:19 ` Miklos Szeredi
2020-01-17 11:37 ` Dr. David Alan Gilbert
2020-01-17 18:43 ` Dr. David Alan Gilbert
2020-01-20 10:17 ` Sergio Lopez
2020-01-20 10:56 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 073/104] virtiofsd: passthrough_ll: clean up cache related options Dr. David Alan Gilbert (git)
2020-01-07 11:24 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 074/104] virtiofsd: passthrough_ll: use hashtable Dr. David Alan Gilbert (git)
2020-01-07 11:28 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 075/104] virtiofsd: Clean up inodes on destroy Dr. David Alan Gilbert (git)
2020-01-07 11:29 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 076/104] virtiofsd: support nanosecond resolution for file timestamp Dr. David Alan Gilbert (git)
2020-01-07 11:30 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 077/104] virtiofsd: fix error handling in main() Dr. David Alan Gilbert (git)
2020-01-07 11:30 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 078/104] virtiofsd: cleanup allocated resource in se Dr. David Alan Gilbert (git)
2020-01-07 11:34 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 079/104] virtiofsd: fix memory leak on lo.source Dr. David Alan Gilbert (git)
2020-01-07 11:37 ` Daniel P. Berrangé
2020-01-09 17:38 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 080/104] virtiofsd: add helper for lo_data cleanup Dr. David Alan Gilbert (git)
2020-01-07 11:40 ` Daniel P. Berrangé
2020-01-09 17:41 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 081/104] virtiofsd: Prevent multiply running with same vhost_user_socket Dr. David Alan Gilbert (git)
2020-01-07 11:43 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 082/104] virtiofsd: enable PARALLEL_DIROPS during INIT Dr. David Alan Gilbert (git)
2020-01-07 11:44 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 083/104] virtiofsd: fix incorrect error handling in lo_do_lookup Dr. David Alan Gilbert (git)
2020-01-07 11:45 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 084/104] Virtiofsd: fix memory leak on fuse queueinfo Dr. David Alan Gilbert (git)
2020-01-15 11:20 ` Misono Tomohiro
2020-01-15 16:57 ` Dr. David Alan Gilbert
2020-01-16 0:54 ` misono.tomohiro
2020-01-16 12:19 ` Dr. David Alan Gilbert
2020-01-20 10:24 ` Sergio Lopez
2020-01-20 10:54 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 085/104] virtiofsd: Support remote posix locks Dr. David Alan Gilbert (git)
2020-01-15 23:38 ` Masayoshi Mizuma
2020-01-16 13:26 ` Vivek Goyal
2020-01-17 9:27 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 086/104] virtiofsd: use fuse_lowlevel_is_virtio() in fuse_session_destroy() Dr. David Alan Gilbert (git)
2020-01-07 12:01 ` Daniel P. Berrangé
2020-01-07 13:24 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 087/104] virtiofsd: prevent fv_queue_thread() vs virtio_loop() races Dr. David Alan Gilbert (git)
2020-01-07 12:02 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 088/104] virtiofsd: make lo_release() atomic Dr. David Alan Gilbert (git)
2020-01-07 12:03 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 089/104] virtiofsd: prevent races with lo_dirp_put() Dr. David Alan Gilbert (git)
2020-01-17 13:52 ` Philippe Mathieu-Daudé
2019-12-12 16:38 ` [PATCH 090/104] virtiofsd: rename inode->refcount to inode->nlookup Dr. David Alan Gilbert (git)
2020-01-17 13:54 ` Philippe Mathieu-Daudé
2019-12-12 16:38 ` [PATCH 091/104] libvhost-user: Fix some memtable remap cases Dr. David Alan Gilbert (git)
2020-01-17 13:58 ` Marc-André Lureau
2020-01-20 15:50 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 092/104] virtiofsd: add man page Dr. David Alan Gilbert (git)
2019-12-13 14:33 ` Liam Merwick
2019-12-13 15:26 ` Dr. David Alan Gilbert
2020-01-07 12:13 ` Daniel P. Berrangé
2020-01-09 20:02 ` Dr. David Alan Gilbert
2020-01-10 9:30 ` Daniel P. Berrangé
2020-01-10 11:06 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 093/104] virtiofsd: introduce inode refcount to prevent use-after-free Dr. David Alan Gilbert (git)
2020-01-16 12:25 ` Misono Tomohiro
2020-01-16 17:21 ` Stefan Hajnoczi
2020-01-16 17:42 ` Dr. David Alan Gilbert
2020-01-17 0:47 ` misono.tomohiro
2020-01-20 10:28 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 094/104] virtiofsd: do not always set FUSE_FLOCK_LOCKS Dr. David Alan Gilbert (git)
2020-01-17 8:50 ` Misono Tomohiro
2020-01-20 10:31 ` Sergio Lopez
2019-12-12 16:38 ` [PATCH 095/104] virtiofsd: convert more fprintf and perror to use fuse log infra Dr. David Alan Gilbert (git)
2020-01-07 12:16 ` Daniel P. Berrangé
2020-01-16 12:29 ` Misono Tomohiro
2020-01-16 16:32 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 096/104] virtiofsd: Reset O_DIRECT flag during file open Dr. David Alan Gilbert (git)
2020-01-07 12:17 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 097/104] virtiofsd: Fix data corruption with O_APPEND wirte in writeback mode Dr. David Alan Gilbert (git)
2020-01-07 12:20 ` Daniel P. Berrangé
2020-01-07 13:27 ` Dr. David Alan Gilbert
2019-12-12 16:38 ` [PATCH 098/104] virtiofsd: add definition of fuse_buf_writev() Dr. David Alan Gilbert (git)
2020-01-07 12:21 ` Daniel P. Berrangé
2019-12-12 16:38 ` [PATCH 099/104] virtiofsd: use fuse_buf_writev to replace fuse_buf_write for better performance Dr. David Alan Gilbert (git)
2020-01-07 12:23 ` Daniel P. Berrangé
2020-01-10 13:15 ` Dr. David Alan Gilbert
2019-12-12 16:39 ` [PATCH 100/104] virtiofsd: process requests in a thread pool Dr. David Alan Gilbert (git)
2020-01-20 12:54 ` Misono Tomohiro
2019-12-12 16:39 ` [PATCH 101/104] virtiofsd: prevent FUSE_INIT/FUSE_DESTROY races Dr. David Alan Gilbert (git)
2020-01-15 23:05 ` Masayoshi Mizuma
2020-01-16 12:24 ` Dr. David Alan Gilbert
2020-01-17 13:40 ` Philippe Mathieu-Daudé
2020-01-17 15:28 ` Dr. David Alan Gilbert
2020-01-17 15:30 ` Philippe Mathieu-Daudé
2019-12-12 16:39 ` [PATCH 102/104] virtiofsd: fix lo_destroy() resource leaks Dr. David Alan Gilbert (git)
2020-01-17 13:43 ` Philippe Mathieu-Daudé
2019-12-12 16:39 ` [PATCH 103/104] virtiofsd: add --thread-pool-size=NUM option Dr. David Alan Gilbert (git)
2020-01-07 12:25 ` Daniel P. Berrangé
2020-01-17 13:35 ` Philippe Mathieu-Daudé
2019-12-12 16:39 ` [PATCH 104/104] virtiofsd: Convert lo_destroy to take the lo->mutex lock itself Dr. David Alan Gilbert (git)
2020-01-17 13:33 ` Philippe Mathieu-Daudé
2019-12-12 18:21 ` [PATCH 000/104] virtiofs daemon [all] no-reply
2020-01-17 11:32 ` Dr. David Alan Gilbert
2020-01-17 13:32 ` [PATCH 105/104] virtiofsd: Unref old/new inodes with the same mutex lock in lo_rename() Philippe Mathieu-Daudé
2020-01-19 8:35 ` Xiao Yang
2020-01-20 8:27 ` Philippe Mathieu-Daudé
2020-01-20 18:52 ` Dr. David Alan Gilbert
2020-01-20 18:55 ` Philippe Mathieu-Daudé
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191212163904.159893-2-dgilbert@redhat.com \
--to=dgilbert@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.com \
--cc=vgoyal@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.