+#include <sys/vnode_if.h>
+
+__BEGIN_DECLS
+
+/*!
+ @function vnode_create
+ @abstract Create and initialize a vnode.
+ @discussion Returns wth an iocount held on the vnode which must eventually be dropped with vnode_put().
+ @param flavor Should be VNCREATE_FLAVOR.
+ @param size Size of the struct vnode_fsparam in "data".
+ @param data Pointer to a struct vnode_fsparam containing initialization information.
+ @param vpp Pointer to a vnode pointer, to be filled in with newly created vnode.
+ @return 0 for success, error code otherwise.
+ */
+errno_t vnode_create(uint32_t flavor, uint32_t size, void *data, vnode_t *vpp);
+
+#ifdef KERNEL_PRIVATE
+/*!
+ @function vnode_create_empty
+ @abstract Create an empty, uninitialized vnode.
+ @discussion Returns with an iocount held on the vnode which must eventually be
+ dropped with vnode_put(). The next operation performed on the vnode must be
+ vnode_initialize (or vnode_put if the vnode is not needed anymore).
+ This interface is provided as a mechanism to pre-flight obtaining a vnode for
+ certain filesystem operations which may need to get a vnode without filesystem
+ locks held. It is imperative that nothing be done with the vnode till the
+ succeeding vnode_initialize (or vnode_put as the case may be) call.
+ @param vpp Pointer to a vnode pointer, to be filled in with newly created vnode.
+ @return 0 for success, error code otherwise.
+ */
+errno_t vnode_create_empty(vnode_t *vpp);
+
+/*!
+ @function vnode_initialize
+ @abstract Initialize a vnode obtained by vnode_create_empty
+ @discussion Does not drop iocount held on the vnode which must eventually be
+ dropped with vnode_put(). In case of an error however, the vnode's iocount is
+ dropped and the vnode must not be referenced again by the caller.
+ @param flavor Should be VNCREATE_FLAVOR.
+ @param size Size of the struct vnode_fsparam in "data".
+ @param data Pointer to a struct vnode_fsparam containing initialization information.
+ @param vpp Pointer to a vnode pointer, to be filled in with newly created vnode.
+ @return 0 for success, error code otherwise.
+ */
+errno_t vnode_initialize(uint32_t flavor, uint32_t size, void *data, vnode_t *vpp);
+#endif /* KERNEL_PRIVATE */
+
+/*!
+ @function vnode_addfsref
+ @abstract Mark a vnode as being stored in a filesystem hash.
+ @discussion Should only be called once on a vnode, and never if that vnode was created with VNFS_ADDFSREF.
+ There should be a corresponding call to vnode_removefsref() when the vnode is reclaimed; VFS assumes that a
+ n unused vnode will not be marked as referenced by a filesystem.
+ @param vp The vnode to mark.
+ @return Always 0.
+ */
+int vnode_addfsref(vnode_t vp);
+
+/*!
+ @function vnode_removefsref
+ @abstract Mark a vnode as no longer being stored in a filesystem hash.
+ @discussion Should only be called once on a vnode (during a reclaim), and only after the vnode has either been created with VNFS_ADDFSREF or marked by vnode_addfsref().
+ @param vp The vnode to unmark.
+ @return Always 0.
+ */
+int vnode_removefsref(vnode_t vp);
+
+/*!
+ @function vnode_hasdirtyblks
+ @abstract Check if a vnode has dirty data waiting to be written to disk.
+ @discussion Note that this routine is unsynchronized; it is only a snapshot and its result may cease to be true at the moment it is returned..
+ @param vp The vnode to test.
+ @return Nonzero if there are dirty blocks, 0 otherwise
+ */
+int vnode_hasdirtyblks(vnode_t vp);
+
+/*!
+ @function vnode_hascleanblks
+ @abstract Check if a vnode has clean buffers associated with it.
+ @discussion Note that this routine is unsynchronized; it is only a snapshot and its result may cease to be true at the moment it is returned..
+ @param vp The vnode to test.
+ @return Nonzero if there are clean blocks, 0 otherwise.
+ */
+int vnode_hascleanblks(vnode_t vp);
+
+#define VNODE_ASYNC_THROTTLE 15
+/*!
+ @function vnode_waitforwrites
+ @abstract Wait for the number of pending writes on a vnode to drop below a target.
+ @param vp The vnode to monitor.
+ @param output_target Max pending write count with which to return.
+ @param slpflag Flags for msleep().
+ @param slptimeout Frequency with which to force a check for completion; increments of 10 ms.
+ @param msg String to pass msleep() .
+ @return 0 for success, or an error value from msleep().
+ */
+int vnode_waitforwrites(vnode_t vp, int output_target, int slpflag, int slptimeout, const char *msg);
+
+/*!
+ @function vnode_startwrite
+ @abstract Increment the count of pending writes on a vnode.
+ @param vp The vnode whose count to increment.
+ */
+void vnode_startwrite(vnode_t vp);
+
+/*!
+ @function vnode_startwrite
+ @abstract Decrement the count of pending writes on a vnode .
+ @discussion Also wakes up threads waiting for the write count to drop, as in vnode_waitforwrites.
+ @param vp The vnode whose count to decrement.
+ */
+void vnode_writedone(vnode_t vp);
+
+/*!
+ @function vnode_vtype
+ @abstract Return a vnode's type.
+ @param vp The vnode whose type to grab.
+ @return The vnode's type.
+ */
+enum vtype vnode_vtype(vnode_t vp);
+
+/*!
+ @function vnode_vid
+ @abstract Return a vnode's vid (generation number), which is constant from creation until reclaim.
+ @param vp The vnode whose vid to grab.
+ @return The vnode's vid.
+ */
+uint32_t vnode_vid(vnode_t vp);
+
+/*!
+ @function vnode_mountedhere
+ @abstract Returns a pointer to a mount placed on top of a vnode, should it exist.
+ @param vp The vnode from whom to take the covering mount.
+ @return Pointer to mount covering a vnode, or NULL if none exists.
+ */
+mount_t vnode_mountedhere(vnode_t vp);
+
+/*!
+ @function vnode_mount
+ @abstract Get the mount structure for the filesystem that a vnode belongs to.
+ @param vp The vnode whose mount to grab.
+ @return The mount, directly.
+ */
+mount_t vnode_mount(vnode_t vp);
+
+/*!
+ @function vnode_specrdev
+ @abstract Return the device id of the device associated with a special file.
+ @param vp The vnode whose device id to extract--vnode must be a special file.
+ @return The device id.
+ */
+dev_t vnode_specrdev(vnode_t vp);
+
+/*!
+ @function vnode_fsnode
+ @abstract Gets the filesystem-specific data associated with a vnode.
+ @param vp The vnode whose data to grab.
+ @return The filesystem-specific data, directly.
+ */
+void * vnode_fsnode(vnode_t vp);
+
+/*!
+ @function vnode_clearfsnode
+ @abstract Sets a vnode's filesystem-specific data to be NULL.
+ @discussion This routine should only be called when a vnode is no longer in use, i.e. during a VNOP_RECLAIM.
+ @param vp The vnode whose data to clear out.
+ */
+void vnode_clearfsnode(vnode_t vp);
+
+/*!
+ @function vnode_isvroot
+ @abstract Determine if a vnode is the root of its filesystem.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is the root, 0 if it is not.
+ */
+int vnode_isvroot(vnode_t vp);
+
+/*!
+ @function vnode_issystem
+ @abstract Determine if a vnode is marked as a System vnode.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is a system vnode, 0 if it is not.
+ */
+int vnode_issystem(vnode_t vp);
+
+/*!
+ @function vnode_ismount
+ @abstract Determine if there is currently a mount occurring which will cover this vnode.
+ @discussion Note that this is only a snapshot; a mount may begin or end at any time.
+ @param vp The vnode to test.
+ @return Nonzero if there is a mount in progress, 0 otherwise.
+ */
+int vnode_ismount(vnode_t vp);
+
+/*!
+ @function vnode_isreg
+ @abstract Determine if a vnode is a regular file.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is of type VREG, 0 otherwise.
+ */
+int vnode_isreg(vnode_t vp);
+
+/*!
+ @function vnode_isdir
+ @abstract Determine if a vnode is a directory.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is of type VDIR, 0 otherwise.
+ */
+int vnode_isdir(vnode_t vp);
+
+/*!
+ @function vnode_islnk
+ @abstract Determine if a vnode is a symbolic link.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is of type VLNK, 0 otherwise.
+ */
+int vnode_islnk(vnode_t vp);
+
+/*!
+ @function vnode_isfifo
+ @abstract Determine if a vnode is a named pipe.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is of type VFIFO, 0 otherwise.
+ */
+int vnode_isfifo(vnode_t vp);
+
+/*!
+ @function vnode_isblk
+ @abstract Determine if a vnode is a block device special file.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is of type VBLK, 0 otherwise.
+ */
+int vnode_isblk(vnode_t vp);
+
+/*!
+ @function vnode_ischr
+ @abstract Determine if a vnode is a character device special file.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is of type VCHR, 0 otherwise.
+ */
+int vnode_ischr(vnode_t vp);
+
+/*!
+ @function vnode_isswap
+ @abstract Determine if a vnode is being used as a swap file.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is being used as swap, 0 otherwise.
+ */
+int vnode_isswap(vnode_t vp);
+
+/*!
+ @function vnode_isnamedstream
+ @abstract Determine if a vnode is a named stream.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is a named stream, 0 otherwise.
+ */
+int vnode_isnamedstream(vnode_t vp);
+
+/*!
+ @function vnode_ismountedon
+ @abstract Determine if a vnode is a block device on which a filesystem has been mounted.
+ @discussion A block device marked as being mounted on cannot be opened.
+ @param vp The vnode to test.
+ @return Nonzero if the vnode is a block device on which an filesystem is mounted, 0 otherwise.
+ */
+int vnode_ismountedon(vnode_t vp);
+
+/*!
+ @function vnode_setmountedon
+ @abstract Set flags indicating that a block device vnode has been mounted as a filesystem.
+ @discussion A block device marked as being mounted on cannot be opened.
+ @param vp The vnode to set flags on, a block device.
+ */
+void vnode_setmountedon(vnode_t vp);
+
+/*!
+ @function vnode_clearmountedon
+ @abstract Clear flags indicating that a block device vnode has been mounted as a filesystem.
+ @param vp The vnode to clear flags on, a block device.
+ */
+void vnode_clearmountedon(vnode_t vp);
+
+/*!
+ @function vnode_isrecycled
+ @abstract Check if a vnode is dead or in the process of being killed (recycled).
+ @discussion This is only a snapshot: a vnode may start to be recycled, or go from dead to in use, at any time.
+ @param vp The vnode to test.
+ @return Nonzero if vnode is dead or being recycled, 0 otherwise.
+ */
+int vnode_isrecycled(vnode_t vp);
+
+/*!
+ @function vnode_isnocache
+ @abstract Check if a vnode is set to not have its data cached in memory (i.e. we write-through to disk and always read from disk).
+ @param vp The vnode to test.
+ @return Nonzero if vnode is set to not have data chached, 0 otherwise.
+ */
+int vnode_isnocache(vnode_t vp);
+
+/*!
+ @function vnode_israge
+ @abstract Check if a vnode is marked for rapid aging
+ @param vp The vnode to test.
+ @return Nonzero if vnode is marked for rapid aging, 0 otherwise
+ */
+int vnode_israge(vnode_t vp);
+
+/*!
+ @function vnode_needssnapshots
+ @abstract Check if a vnode needs snapshots events (regardless of its ctime status)
+ @param vp The vnode to test.
+ @return Nonzero if vnode needs snapshot events, 0 otherwise
+ */
+int vnode_needssnapshots(vnode_t vp);
+
+/*!
+ @function vnode_setnocache
+ @abstract Set a vnode to not have its data cached in memory (i.e. we write-through to disk and always read from disk).
+ @param vp The vnode whose flags to set.
+ */
+void vnode_setnocache(vnode_t vp);
+
+/*!
+ @function vnode_clearnocache
+ @abstract Clear the flag on a vnode indicating that data should not be cached in memory (i.e. we write-through to disk and always read from disk).
+ @param vp The vnode whose flags to clear.
+ */
+void vnode_clearnocache(vnode_t vp);
+
+/*!
+ @function vnode_isnoreadahead
+ @abstract Check if a vnode is set to not have data speculatively read in in hopes of future cache hits.
+ @param vp The vnode to test.
+ @return Nonzero if readahead is disabled, 0 otherwise.
+ */
+int vnode_isnoreadahead(vnode_t vp);
+
+/*!
+ @function vnode_setnoreadahead
+ @abstract Set a vnode to not have data speculatively read in in hopes of hitting in cache.
+ @param vp The vnode on which to prevent readahead.
+ */
+void vnode_setnoreadahead(vnode_t vp);
+
+/*!
+ @function vnode_clearnoreadahead
+ @abstract Clear the flag indicating that a vnode should not have data speculatively read in.
+ @param vp The vnode whose flag to clear.
+ */
+void vnode_clearnoreadahead(vnode_t vp);
+
+/*!
+ @function vnode_isfastdevicecandidate
+ @abstract Check if a vnode is a candidate to store on the fast device of a composite disk system
+ @param vp The vnode which you want to test.
+ @return Nonzero if the vnode is marked as a fast-device candidate
+ */
+int vnode_isfastdevicecandidate(vnode_t vp);
+
+/*!
+ @function vnode_setfastdevicecandidate
+ @abstract Mark a vnode as a candidate to store on the fast device of a composite disk system
+ @discussion If the vnode is a directory, all its children will inherit this bit.
+ @param vp The vnode which you want marked.
+ */
+void vnode_setfastdevicecandidate(vnode_t vp);
+
+/*!
+ @function vnode_clearfastdevicecandidate
+ @abstract Clear the status of a vnode being a candidate to store on the fast device of a composite disk system.
+ @param vp The vnode whose flag to clear.
+ */
+void vnode_clearfastdevicecandidate(vnode_t vp);
+
+/*!
+ @function vnode_isautocandidate
+ @abstract Check if a vnode was automatically selected to be fast-dev candidate (see vnode_setfastdevicecandidate)
+ @param vp The vnode which you want to test.
+ @return Nonzero if the vnode was automatically marked as a fast-device candidate
+ */
+int vnode_isautocandidate(vnode_t vp);
+
+/*!
+ @function vnode_setfastdevicecandidate
+ @abstract Mark a vnode as an automatically selected candidate for storing on the fast device of a composite disk system
+ @discussion If the vnode is a directory, all its children will inherit this bit.
+ @param vp The vnode which you want marked.
+ */
+void vnode_setautocandidate(vnode_t vp);
+
+/*!
+ @function vnode_clearautocandidate
+ @abstract Clear the status of a vnode being an automatic candidate (see above)
+ @param vp The vnode whose flag to clear.
+ */
+void vnode_clearautocandidate(vnode_t vp);
+
+/* left only for compat reasons as User code depends on this from getattrlist, for ex */
+
+/*!
+ @function vnode_settag
+ @abstract Set a vnode filesystem-specific "tag."
+ @discussion Sets a tag indicating which filesystem a vnode belongs to, e.g. VT_HFS, VT_UDF, VT_ZFS. The kernel never inspects this data, though the filesystem tags are defined in vnode.h; it is for the benefit of user programs via getattrlist.
+ @param vp The vnode whose tag to set.
+ */
+void vnode_settag(vnode_t vp, int tag);
+
+/*!
+ @function vnode_tag
+ @abstract Get the vnode filesystem-specific "tag."
+ @discussion Gets the tag indicating which filesystem a vnode belongs to, e.g. VT_HFS, VT_UDF, VT_ZFS. The kernel never inspects this data, though the filesystem tags are defined in vnode.h; it is for the benefit of user programs via getattrlist.
+ @param vp The vnode whose tag to grab.
+ @return The tag.
+ */
+int vnode_tag(vnode_t vp);
+
+/*!
+ @function vnode_getattr
+ @abstract Get vnode attributes.
+ @discussion Desired attributes are set with VATTR_SET_ACTIVE and VNODE_ATTR* macros. Supported attributes are determined after call with VATTR_IS_SUPPORTED.
+ @param vp The vnode whose attributes to grab.
+ @param vap Structure containing: 1) A list of requested attributes 2) Space to indicate which attributes are supported and being returned 3) Space to return attributes.
+ @param ctx Context for authentication.
+ @return 0 for success or an error code.
+ */
+int vnode_getattr(vnode_t vp, struct vnode_attr *vap, vfs_context_t ctx);
+
+/*!
+ @function vnode_setattr
+ @abstract Set vnode attributes.
+ @discussion Attributes to set are marked with VATTR_SET_ACTIVE and VNODE_ATTR* macros. Attributes successfully set are determined after call with VATTR_IS_SUPPORTED.
+ @param vp The vnode whose attributes to set.
+ @param vap Structure containing: 1) A list of attributes to set 2) Space for values for those attributes 3) Space to indicate which attributes were set.
+ @param ctx Context for authentication.
+ @return 0 for success or an error code.
+ */
+int vnode_setattr(vnode_t vp, struct vnode_attr *vap, vfs_context_t ctx);
+
+/*!
+ @function vfs_rootvnode
+ @abstract Returns the root vnode with an iocount.
+ @discussion Caller must vnode_put() the root node when done.
+ @return Pointer to root vnode if successful; error code if there is a problem taking an iocount.
+ */
+vnode_t vfs_rootvnode(void);
+
+/*!
+ @function vnode_uncache_credentials
+ @abstract Clear out cached credentials on a vnode.
+ @discussion When we authorize an action on a vnode, we cache the credential that was authorized and the actions it was authorized for in case a similar request follows. This function destroys that caching.
+ @param vp The vnode whose cache to clear.
+ */
+void vnode_uncache_credentials(vnode_t vp);
+
+/*!
+ @function vnode_setmultipath
+ @abstract Mark a vnode as being reachable by multiple paths, i.e. as a hard link.
+ @discussion "Multipath" vnodes can be reached through more than one entry in the filesystem, and so must be handled differently for caching and event notification purposes. A filesystem should mark a vnode with multiple hardlinks this way.
+ @param vp The vnode to mark.
+ */
+void vnode_setmultipath(vnode_t vp);
+
+/*!
+ @function vnode_vfsmaxsymlen
+ @abstract Determine the maximum length of a symbolic link for the filesystem on which a vnode resides.
+ @param vp The vnode for which to get filesystem symlink size cap.
+ @return Max symlink length.
+ */
+uint32_t vnode_vfsmaxsymlen(vnode_t vp);
+
+/*!
+ @function vnode_vfsisrdonly
+ @abstract Determine if the filesystem to which a vnode belongs is mounted read-only.
+ @param vp The vnode for which to get filesystem writeability.
+ @return Nonzero if the filesystem is read-only, 0 otherwise.
+ */
+int vnode_vfsisrdonly(vnode_t vp);
+
+/*!
+ @function vnode_vfstypenum
+ @abstract Get the "type number" of the filesystem to which a vnode belongs.
+ @discussion This is an archaic construct; most filesystems are assigned a type number based on the order in which they are registered with the system.
+ @param vp The vnode whose filesystem to examine.
+ @return The type number of the fileystem to which the vnode belongs.
+ */
+int vnode_vfstypenum(vnode_t vp);
+
+/*!
+ @function vnode_vfsname
+ @abstract Get the name of the filesystem to which a vnode belongs.
+ @param vp The vnode whose filesystem to examine.
+ @param buf Destination for vfs name: should have size MFSNAMELEN or greater.
+ */
+void vnode_vfsname(vnode_t vp, char *buf);
+
+/*!
+ @function vnode_vfs64bitready
+ @abstract Determine if the filesystem to which a vnode belongs is marked as ready to interact with 64-bit user processes.
+ @param vp The vnode whose filesystem to examine.
+ @return Nonzero if filesystem is marked ready for 64-bit interactions; 0 otherwise.
+ */
+int vnode_vfs64bitready(vnode_t vp);
+
+/* These should move to private ... not documenting for now */
+int vfs_context_get_special_port(vfs_context_t, int, ipc_port_t *);
+int vfs_context_set_special_port(vfs_context_t, int, ipc_port_t);
+
+/*!
+ @function vfs_context_proc
+ @abstract Get the BSD process structure associated with a vfs_context_t.
+ @param ctx Context whose associated process to find.
+ @return Process if available, NULL otherwise.
+ */
+proc_t vfs_context_proc(vfs_context_t ctx);
+
+/*!
+ @function vfs_context_ucred
+ @abstract Get the credential associated with a vfs_context_t.
+ @discussion Succeeds if and only if the context has a thread, the thread has a task, and the task has a BSD proc.
+ @param ctx Context whose associated process to find.
+ @returns credential if process available; NULL otherwise
+ */
+kauth_cred_t vfs_context_ucred(vfs_context_t ctx);
+
+/*!
+ @function vfs_context_pid
+ @abstract Get the process id of the BSD process associated with a vfs_context_t.
+ @param ctx Context whose associated process to find.
+ @return Process id.
+ */
+int vfs_context_pid(vfs_context_t ctx);
+
+/*!
+ @function vfs_context_issignal
+ @abstract Get a bitfield of pending signals for the BSD process associated with a vfs_context_t.
+ @discussion The bitfield is constructed using the sigmask() macro, in the sense of bits |= sigmask(SIGSEGV).
+ @param ctx Context whose associated process to find.
+ @return Bitfield of pending signals.
+ */
+int vfs_context_issignal(vfs_context_t ctx, sigset_t mask);
+
+/*!
+ @function vfs_context_suser
+ @abstract Determine if a vfs_context_t corresponds to the superuser.
+ @param ctx Context to examine.
+ @return 0 if context belongs to superuser, EPERM otherwise.
+ */
+int vfs_context_suser(vfs_context_t ctx);
+
+/*!
+ @function vfs_context_is64bit
+ @abstract Determine if a vfs_context_t corresponds to a 64-bit user process.
+ @param ctx Context to examine.
+ @return Nonzero if context is of 64-bit process, 0 otherwise.
+ */
+int vfs_context_is64bit(vfs_context_t ctx);
+
+/*!
+ @function vfs_context_create
+ @abstract Create a new vfs_context_t with appropriate references held.
+ @discussion The context must be released with vfs_context_rele() when no longer in use.
+ @param ctx Context to copy, or NULL to use information from running thread.
+ @return The new context, or NULL in the event of failure.
+ */
+vfs_context_t vfs_context_create(vfs_context_t ctx);
+
+/*!
+ @function vfs_context_rele
+ @abstract Release references on components of a context and deallocate it.
+ @discussion A context should not be referenced after vfs_context_rele has been called.
+ @param ctx Context to release.
+ @return Always 0.
+ */
+int vfs_context_rele(vfs_context_t ctx);
+
+/*!
+ @function vfs_context_current
+ @abstract Get the vfs_context for the current thread, or the kernel context if there is no context for current thread.
+ @discussion Kexts should not use this function--it is preferred to use vfs_context_create(NULL) and vfs_context_rele(), which ensure proper reference counting of underlying structures.
+ @return Context for current thread, or kernel context if thread context is unavailable.
+ */
+vfs_context_t vfs_context_current(void);
+#ifdef KERNEL_PRIVATE
+int vfs_context_bind(vfs_context_t);
+
+/*!
+ @function vfs_ctx_skipatime
+ @abstract Check to see if this context should skip updating a vnode's access times.
+ @discussion This is currently tied to the vnode rapid aging process. If the process is marked for rapid aging,
+ then the kernel should not update vnodes it touches for access time purposes. This will check to see if the
+ specified process and/or thread is marked for rapid aging when it manipulates vnodes.
+ @param ctx The context being investigated.
+ @return 1 if we should skip access time updates.
+ @return 0 if we should NOT skip access time updates.
+ */
+
+int vfs_ctx_skipatime(vfs_context_t ctx);
+
+#endif
+
+/*!
+ @function vflush
+ @abstract Reclaim the vnodes associated with a mount.
+ @param mp The mount whose vnodes to kill.
+ @param skipvp A specific vnode to not reclaim or to let interrupt an un-forced flush
+ @param flags Control which
+ @discussion This function is used to clear out the vnodes associated with a mount as part of the unmount process.
+ Its parameters can determine which vnodes to skip in the process and whether in-use vnodes should be forcibly reclaimed.
+ Filesystems should call this function from their unmount code, because VFS code will always call it with SKIPROOT | SKIPSWAP | SKIPSYSTEM; filesystems
+ must take care of such vnodes themselves.
+ SKIPSYSTEM skip vnodes marked VSYSTEM
+ FORCECLOSE force file closeure
+ WRITECLOSE only close writeable files
+ SKIPSWAP skip vnodes marked VSWAP
+ SKIPROOT skip root vnodes marked VROOT
+ @return 0 for success, EBUSY if vnodes were busy and FORCECLOSE was not set.
+ */
+int vflush(struct mount *mp, struct vnode *skipvp, int flags);
+
+/*!
+ @function vnode_get
+ @abstract Increase the iocount on a vnode.
+ @discussion If vnode_get() succeeds, the resulting io-reference must be dropped with vnode_put().
+ This function succeeds unless the vnode in question is dead or in the process of dying AND the current iocount is zero.
+ This means that it can block an ongoing reclaim which is blocked behind some other iocount.
+
+ On success, vnode_get() returns with an iocount held on the vnode; this type of reference is intended to be held only for short periods of time (e.g.
+ across a function call) and provides a strong guarantee about the life of the vnode; vnodes with positive iocounts cannot be
+ recycled, and an iocount is required for any operation on a vnode. However, vnode_get() does not provide any guarantees
+ about the identity of the vnode it is called on; unless there is a known existing iocount on the vnode at time the call is made,
+ it could be recycled and put back in use before the vnode_get() succeeds, so the caller may be referencing a
+ completely different vnode than was intended. vnode_getwithref() and vnode_getwithvid()
+ provide guarantees about vnode identity.
+
+ @return 0 for success, ENOENT if the vnode is dead and without existing io-reference.
+ */
+int vnode_get(vnode_t);
+
+/*!
+ @function vnode_getwithvid
+ @abstract Increase the iocount on a vnode, checking that the vnode is alive and has not changed vid (i.e. been recycled)
+ @discussion If vnode_getwithvid() succeeds, the resulting io-reference must be dropped with vnode_put().
+ This function succeeds unless the vnode in question is dead, in the process of dying, or has been recycled (and given a different vnode id).
+ The intended usage is that a vnode is stored and its vid (vnode_vid(vp)) recorded while an iocount is held (example: a filesystem hash). The
+ iocount is then dropped, and time passes (perhaps locks are dropped and picked back up). Subsequently, vnode_getwithvid() is called to get an iocount,
+ but we are alerted if the vnode has been recycled.
+
+ On success, vnode_getwithvid() returns with an iocount held on the vnode; this type of reference is intended to be held only for short periods of time (e.g.
+ across a function call) and provides a strong guarantee about the life of the vnode. vnodes with positive iocounts cannot be
+ recycled. An iocount is required for any operation on a vnode.
+ @return 0 for success, ENOENT if the vnode is dead, in the process of being reclaimed, or has been recycled and reused.
+ */
+int vnode_getwithvid(vnode_t, uint32_t);
+
+#ifdef BSD_KERNEL_PRIVATE
+int vnode_getwithvid_drainok(vnode_t, uint32_t);
+#endif /* BSD_KERNEL_PRIVATE */
+
+/*!
+ @function vnode_getwithref
+ @abstract Increase the iocount on a vnode on which a usecount (persistent reference) is held.
+ @discussion If vnode_getwithref() succeeds, the resulting io-reference must be dropped with vnode_put().
+ vnode_getwithref() will succeed on dead vnodes; it should fail with ENOENT on vnodes which are in the process of being reclaimed.
+ Because it is only called with a usecount on the vnode, the caller is guaranteed that the vnode has not been
+ reused for a different file, though it may now be dead and have deadfs vnops (which return errors like EIO, ENXIO, ENOTDIR).
+ On success, vnode_getwithref() returns with an iocount held on the vnode; this type of reference is intended to be held only for short periods of time (e.g.
+ across a function call) and provides a strong guarantee about the life of the vnode. vnodes with positive iocounts cannot be
+ recycled. An iocount is required for any operation on a vnode.
+ @return 0 for success, ENOENT if the vnode is dead, in the process of being reclaimed, or has been recycled and reused.
+ */
+int vnode_getwithref(vnode_t vp);
+
+/*!
+ @function vnode_put
+ @abstract Decrement the iocount on a vnode.
+ @discussion vnode_put() is called to indicate that a vnode is no longer in active use. It removes the guarantee that a
+ vnode will not be recycled. This routine should be used to release io references no matter how they were obtained.
+ @param vp The vnode whose iocount to drop.
+ @return Always 0.
+ */
+int vnode_put(vnode_t vp);
+
+/*!
+ @function vnode_ref
+ @abstract Increment the usecount on a vnode.
+ @discussion If vnode_ref() succeeds, the resulting usecount must be released with vnode_rele(). vnode_ref() is called to obtain
+ a persistent reference on a vnode. This type of reference does not provide the same strong guarantee that a vnode will persist
+ as does an iocount--it merely ensures that a vnode will not be reused to represent a different file. However, a usecount may be
+ held for extended periods of time, whereas an iocount is intended to be obtained and released quickly as part of performing a
+ vnode operation. A holder of a usecount must call vnode_getwithref()/vnode_put() in order to perform any operations on that vnode.
+ @param vp The vnode on which to obtain a persistent reference.
+ @return 0 for success; ENOENT if the vnode is dead or in the process of being recycled AND the calling thread is not the vnode owner.
+ */
+int vnode_ref(vnode_t vp);
+
+/*!
+ @function vnode_rele
+ @abstract Decrement the usecount on a vnode.
+ @discussion vnode_rele() is called to relese a persistent reference on a vnode. Releasing the last usecount
+ opens the door for a vnode to be reused as a new file; it also triggers a VNOP_INACTIVE call to the filesystem,
+ though that will not happen immediately if there are outstanding iocount references.
+ @param vp The vnode whose usecount to drop.
+ */
+void vnode_rele(vnode_t vp);
+
+/*!
+ @function vnode_isinuse
+ @abstract Determine if the number of persistent (usecount) references on a vnode is greater than a given count.
+ @discussion vnode_isinuse() compares a vnode's usecount (corresponding to vnode_ref() calls) to its refcnt parameter
+ (the number of references the caller expects to be on the vnode). Note that "kusecount" references, corresponding
+ to parties interested only in event notifications, e.g. open(..., O_EVTONLY), are not counted towards the total; the comparison is
+ (usecount - kusecount > recnt). It is
+ also important to note that the result is only a snapshot; usecounts can change from moment to moment, and the result of vnode_isinuse
+ may no longer be correct the very moment that the caller receives it.
+ @param vp The vnode whose use-status to check.
+ @param refcnt The threshold for saying that a vnode is in use.
+ */
+int vnode_isinuse(vnode_t vp, int refcnt);
+
+/*!
+ @function vnode_recycle
+ @abstract Cause a vnode to be reclaimed and prepared for reuse.
+ @discussion Like all vnode KPIs, must be called with an iocount on the target vnode.
+ vnode_recycle() will mark that vnode for reclaim when all existing references are dropped.
+ @param vp The vnode to recycle.
+ @return 1 if the vnode was reclaimed (i.e. there were no existing references), 0 if it was only marked for future reclaim.
+ */
+int vnode_recycle(vnode_t vp);
+
+#ifdef KERNEL_PRIVATE
+
+#define VNODE_EVENT_DELETE 0x00000001 /* file was removed */
+#define VNODE_EVENT_WRITE 0x00000002 /* file or directory contents changed */
+#define VNODE_EVENT_EXTEND 0x00000004 /* ubc size increased */
+#define VNODE_EVENT_ATTRIB 0x00000008 /* attributes changed (suitable for permission changes if type unknown)*/
+#define VNODE_EVENT_LINK 0x00000010 /* link count changed */
+#define VNODE_EVENT_RENAME 0x00000020 /* vnode was renamed */
+#define VNODE_EVENT_PERMS 0x00000040 /* permissions changed: will cause a NOTE_ATTRIB */
+#define VNODE_EVENT_FILE_CREATED 0x00000080 /* file created in directory: will cause NOTE_WRITE */
+#define VNODE_EVENT_DIR_CREATED 0x00000100 /* directory created inside this directory: will cause NOTE_WRITE */
+#define VNODE_EVENT_FILE_REMOVED 0x00000200 /* file removed from this directory: will cause NOTE_WRITE */
+#define VNODE_EVENT_DIR_REMOVED 0x00000400 /* subdirectory from this directory: will cause NOTE_WRITE */
+
+#ifdef BSD_KERNEL_PRIVATE
+#define VNODE_NOTIFY_ATTRS (VNODE_ATTR_BIT(va_fsid) | \
+ VNODE_ATTR_BIT(va_fileid)| \
+ VNODE_ATTR_BIT(va_mode) | \
+ VNODE_ATTR_BIT(va_uid) | \
+ VNODE_ATTR_BIT(va_gid) | \
+ VNODE_ATTR_BIT(va_dirlinkcount) | \
+ VNODE_ATTR_BIT(va_nlink))
+
+
+
+#endif /* BSD_KERNEL_PRIVATE */
+
+/*!
+ @function vnode_ismonitored
+ @abstract Check whether a file has watchers that would make it useful to query a server
+ for file changes.
+ @param vp Vnode to examine.
+ @discussion Will not reenter the filesystem.
+ @return Zero if not monitored, nonzero if monitored.
+ */
+int vnode_ismonitored(vnode_t vp);
+
+
+/*!
+ @function vnode_isdyldsharedcache
+ @abstract Check whether a file is a dyld shared cache file.
+ @param vp Vnode to examine.
+ @discussion Will not reenter the filesystem.
+ @return nonzero if a dyld shared cache file, zero otherwise.
+ */
+int vnode_isdyldsharedcache(vnode_t vp);
+
+
+/*!
+ @function vn_getpath_fsenter
+ @abstract Attempt to get a vnode's path, willing to enter the filesystem.
+ @discussion Paths to vnodes are not always straightforward: a file with multiple hard-links will have multiple pathnames,
+ and it is sometimes impossible to determine a vnode's full path. vn_getpath_fsenter() may enter the filesystem
+ to try to construct a path, so filesystems should be wary of calling it.
+ @param vp Vnode whose path to get
+ @param pathbuf Buffer in which to store path.
+ @param len Destination for length of resulting path string. Result will include NULL-terminator in count--that is, "len"
+ will be strlen(pathbuf) + 1.
+ @return 0 for success or an error.
+ */
+int vn_getpath_fsenter(struct vnode *vp, char *pathbuf, int *len);
+
+/*!
+ @function vn_getpath_fsenter_with_parent
+ @abstract Attempt to get a vnode's path by entering the file system if needed given a vnode and it's directory vnode.
+ @discussion Same as vn_getpath_fsenter but is given the directory vnode as well as the target vnode. Used
+to get the path from the vnode while performing rename, rmdir, and unlink. This is done to avoid potential
+dead lock if another thread is doing a forced unmount.
+ @param dvp Containing directory vnode. Must be holding an IO count.
+ @param vp Vnode whose path to get. Must be holding an IO count.
+ @param pathbuf Buffer in which to store path.
+ @param len Destination for length of resulting path string. Result will include NULL-terminator in count--that is, "len"
+ will be strlen(pathbuf) + 1.
+ @return 0 for success or an error.
+*/
+int vn_getpath_fsenter_with_parent(struct vnode *dvp, struct vnode *vp, char *pathbuf, int *len);
+
+#endif /* KERNEL_PRIVATE */
+
+#define VNODE_UPDATE_PARENT 0x01
+#define VNODE_UPDATE_NAME 0x02
+#define VNODE_UPDATE_CACHE 0x04
+#define VNODE_UPDATE_PURGE 0x08
+/*!
+ @function vnode_update_identity
+ @abstract Update vnode data associated with the vfs cache.
+ @discussion The vfs namecache is central to tracking vnode-identifying data and to locating files on the system. vnode_update_identity()
+ is used to update vnode data associated with the cache. It can set a vnode's parent and/or name (also potentially set by vnode_create())
+ or flush cache data.
+ @param vp The vnode whose information to update.
+ @param dvp Parent to set on the vnode if VNODE_UPDATE_PARENT is used.
+ @param name Name to set in the cache for the vnode if VNODE_UPDATE_NAME is used. The buffer passed in can be subsequently freed, as the cache
+ does its own name storage. String should be NULL-terminated unless length and hash value are specified.
+ @param name_len Length of name, if known. Passing 0 causes the cache to determine the length itself.
+ @param name_hashval Hash value of name, if known. Passing 0 causes the cache to hash the name itself.
+ @param flags VNODE_UPDATE_PARENT: set parent. VNODE_UPDATE_NAME: set name. VNODE_UPDATE_CACHE: flush cache entries for hard links
+ associated with this file. VNODE_UPDATE_PURGE: flush cache entries for hard links and children of this file.
+ */
+void vnode_update_identity(vnode_t vp, vnode_t dvp, const char *name, int name_len, uint32_t name_hashval, int flags);
+
+/*!
+ @function vn_bwrite
+ @abstract System-provided implementation of "bwrite" vnop.
+ @discussion This routine is available for filesystems which do not want to implement their own "bwrite" vnop. It just calls
+ buf_bwrite() without modifying its arguments.
+ @param ap Standard parameters to a bwrite vnop.
+ @return Results of buf_bwrite directly.
+ */
+int vn_bwrite(struct vnop_bwrite_args *ap);
+
+/*!
+ @function vnode_authorize
+ @abstract Authorize a kauth-style action on a vnode.
+ @discussion Operations on dead vnodes are always allowed (though never do anything).
+ @param vp Vnode on which to authorize action.
+ @param dvp Parent of "vp," can be NULL.
+ @param action Action to authorize, e.g. KAUTH_VNODE_READ_DATA. See bsd/sys/kauth.h.
+ @param ctx Context for which to authorize actions.
+ @return EACCESS if permission is denied. 0 if operation allowed. Various errors from lower layers.
+ */
+int vnode_authorize(vnode_t vp, vnode_t dvp, kauth_action_t action, vfs_context_t ctx);
+
+#ifdef KERNEL_PRIVATE
+/*!
+ @function vnode_attr_authorize_init
+ @abstract Initialize attributes for authorization of a kauth-style action on a file system object based on its attributes.
+ @discussion This function tells the caller what attributes may be required for a authorizing
+ a kauth style action.
+ @param vap attributes of file system object on which to authorize action.
+ @param dvap attributes of parent of file system object, can be NULL.
+ @param action Action to authorize, e.g. KAUTH_VNODE_READ_DATA. See bsd/sys/kauth.h.
+ @param ctx Context for which to authorize actions.
+ @return EINVAL if a required parameters are not passed (for eg. not passing dvap when the action is KAUTH_ACTION_DELETE), 0 otherwise.
+ */
+#define VNODE_ATTR_AUTHORIZE_AVAILABLE 0x01
+int vnode_attr_authorize_init(struct vnode_attr *vap, struct vnode_attr *dvap, kauth_action_t action, vfs_context_t ctx);
+
+/*!
+ @function vnode_attr_authorize
+ @abstract Authorize a kauth-style action on a file system object based on its attributes.
+ @discussion This function should be preceded by a call to vnode_attr_authorize_init to get what attributes are required.
+ @param vap attributes of file system object on which to authorize action.
+ @param dvap attributes of parent of file system object, can be NULL.
+ @param mp mountpoint to which file system object belongs, can be NULL.
+ @param action Action to authorize, e.g. KAUTH_VNODE_READ_DATA. See bsd/sys/kauth.h.
+ @param ctx Context for which to authorize actions.
+ @return EACCESS if permission is denied. 0 if operation allowed. Various errors from lower layers.
+ */
+int vnode_attr_authorize(struct vnode_attr *vap, struct vnode_attr *dvap, mount_t mp, kauth_action_t action, vfs_context_t ctx);
+#endif /* KERNEL_PRIVATE */
+
+/*!
+ @function vnode_authattr
+ @abstract Given a vnode_attr structure, determine what kauth-style actions must be authorized in order to set those attributes.
+ @discussion vnode_authorize requires kauth-style actions; if we want to set a vnode_attr structure on a vnode, we need to translate
+ the set of attributes to a set of kauth-style actions. This routine will return errors for certain obviously disallowed, or
+ incoherent, actions.
+ @param vp The vnode on which to authorize action.
+ @param vap Pointer to vnode_attr struct containing desired attributes to set and their values.
+ @param actionp Destination for set of actions to authorize
+ @param ctx Context for which to authorize actions.
+ @return 0 (and a result in "actionp" for success. Otherwise, an error code.
+ */
+int vnode_authattr(vnode_t vp, struct vnode_attr *vap, kauth_action_t *actionp, vfs_context_t ctx);
+
+/*!
+ @function vnode_authattr_new
+ @abstract Initialize and validate file creation parameters with respect to the current context.
+ @discussion vnode_authattr_new() will fill in unitialized values in the vnode_attr struct with defaults, and will validate the structure
+ with respect to the current context for file creation.
+ @param dvp The directory in which creation will occur.
+ @param vap Pointer to vnode_attr struct containing desired attributes to set and their values.
+ @param noauth If 1, treat the caller as the superuser, i.e. do not check permissions.
+ @param ctx Context for which to authorize actions.
+ @return KAUTH_RESULT_ALLOW for success, an error to indicate invalid or disallowed attributes.
+ */
+int vnode_authattr_new(vnode_t dvp, struct vnode_attr *vap, int noauth, vfs_context_t ctx);
+
+/*!
+ @function vnode_close
+ @abstract Close a file as opened with vnode_open().
+ @discussion vnode_close() drops the refcount (persistent reference) picked up in vnode_open() and calls down to the filesystem with VNOP_CLOSE. It should
+ be called with both an iocount and a refcount on the vnode and will drop both.
+ @param vp The vnode to close.
+ @param flags Flags to close: FWASWRITTEN indicates that the file was written to.
+ @param ctx Context against which to validate operation.
+ @return 0 for success or an error from the filesystem.
+ */
+errno_t vnode_close(vnode_t vp, int flags, vfs_context_t ctx);
+
+/*!
+ @function vn_getpath
+ @abstract Construct the path to a vnode.
+ @discussion Paths to vnodes are not always straightforward: a file with multiple hard-links will have multiple pathnames,
+ and it is sometimes impossible to determine a vnode's full path. vn_getpath() will not enter the filesystem.
+ @param vp The vnode whose path to obtain.
+ @param pathbuf Destination for pathname; should be of size MAXPATHLEN
+ @param len Destination for length of resulting path string. Result will include NULL-terminator in count--that is, "len"
+ will be strlen(pathbuf) + 1.
+ @return 0 for success or an error code.
+ */
+int vn_getpath(struct vnode *vp, char *pathbuf, int *len);
+
+/*!
+ @function vnode_notify
+ @abstract Send a notification up to VFS.
+ @param vp Vnode for which to provide notification.
+ @param vap Attributes for that vnode, to be passed to fsevents.
+ @discussion Filesystem determines which attributes to pass up using
+ vfs_get_notify_attributes(&vap). The most specific events possible should be passed,
+ e.g. VNODE_EVENT_FILE_CREATED on a directory rather than just VNODE_EVENT_WRITE, but
+ a less specific event can be passed up if more specific information is not available.
+ Will not reenter the filesystem.
+ @return 0 for success, else an error code.
+ */
+int vnode_notify(vnode_t vp, uint32_t events, struct vnode_attr *vap);
+
+/*!
+ @function vfs_get_notify_attributes
+ @abstract Determine what attributes are required to send up a notification with vnode_notify().
+ @param vap Structure to initialize and activate required attributes on.
+ @discussion Will not reenter the filesystem.
+ @return 0 for success, nonzero for error (currently always succeeds).
+ */
+int vfs_get_notify_attributes(struct vnode_attr *vap);
+
projects / apple / xnu.git / blobdiff