+vnode_t vfs_devvp(mount_t mp); /* Please see block comment with implementation */
+int vfs_nativexattrs (mount_t mp); /* whether or not the FS supports EAs natively */
+void * vfs_mntlabel(mount_t mp); /* Safe to cast to "struct label*"; returns "void*" to limit dependence of mount.h on security headers. */
+void vfs_setcompoundopen(mount_t mp);
+uint64_t vfs_throttle_mask(mount_t mp);
+int vfs_isswapmount(mount_t mp);
+
+struct vnode_trigger_info;
+
+/*!
+ @function vfs_addtrigger
+ @abstract Create an "external" trigger vnode: look up a vnode and mark it as
+ a trigger. Can only safely be called in the context of a callback set by
+ vfs_settriggercallback(). May only be used on a file which is not already
+ marked as a trigger.
+ @param relpath Path relative to root of mountpoint at which to mark trigger.
+ @param vtip Information about trigger; analogous to "vnode_trigger_param"
+ argument to vnode_create.
+ @param ctx Authorization context.
+ */
+int vfs_addtrigger(mount_t mp, const char *relpath, struct vnode_trigger_info *vtip, vfs_context_t ctx);
+
+
+/*!
+ @enum vfs_trigger_callback_op_t
+ @abstract Operation to perform after an attempted unmount (successful or otherwise).
+ @constant VTC_REPLACE Unmount failed: attempt to replace triggers. Only valid
+ VFS operation to perform in this context is vfs_addtrigger().
+ @constant VTC_RELEASE Unmount succeeded: release external triggering context.
+ */
+typedef enum {
+ VTC_REPLACE,
+ VTC_RELEASE
+} vfs_trigger_callback_op_t;
+
+/*!
+ @typedef vfs_trigger_callback_t
+ @abstract Callback to be passed to vfs_settriggercallback() and invoked from
+ unmount context.
+ @param mp Mountpoint on which unmount is occurring.
+ @param op Operation (see vfs_trigger_callback_op_t)
+ @param data Context passed to vfs_settriggercallback()
+ @param ctx Authorization context in which unmount is occurring.
+ */
+typedef void vfs_trigger_callback_t(mount_t mp, vfs_trigger_callback_op_t op, void *data, vfs_context_t ctx);
+
+/*!
+ @function vfs_settriggercallback
+ @abstract Install a callback to be called after unmount attempts on a volume,
+ to restore triggers for failed unmounts and release state for successful ones.
+ @discussion Installs a callback which will be called in two situations: a
+ failed unmount where vnodes may have been reclaimed and a successful unmount.
+ Gives an external trigger-marking entity an opportunity to replace triggers
+ which may have been reclaimed. The callback can only be installed (not
+ cleared), and only one callback can be installed. The callback will be called
+ with a read-write lock held on the mount point; in the VTC_REPLACE case, the
+ <em>only</em> valid VFS operation to perform in the context of the callback is
+ vfs_addtrigger() on the mountpoint in question. This rwlock is held in order
+ to attempt to provide some modicum of coverage from lookups which might find
+ missing trigger vnodes and receive spurious ENOENTs. Note that this
+ protection is incomplete--current working directories, or traversals up into a
+ volume via ".." may still find missing triggers. As of this writing, no
+ serialization mechanism exists to do better than this.
+ When the "op" is VTC_RELEASE, the mountpoint is going away, and the only valid
+ VFS operation is to free the private data pointer if needed. The callback
+ will be called immediately, with VTC_REPLACE, from vfs_settriggercallback(),
+ if installation is successful.
+ @param fsid FSID for filesystem in question.
+ @param vtc Callback pointer.
+ @param data Context pointer to be passed to callback.
+ @param flags Currently unused.
+ @param ctx Authorization context.
+ @return 0 for success. EBUSY if a trigger has already been installed.
+ */
+int vfs_settriggercallback(fsid_t *fsid, vfs_trigger_callback_t vtc, void *data, uint32_t flags, vfs_context_t ctx);
+
+/* tags a volume as not supporting extended readdir for NFS exports */
+void mount_set_noreaddirext (mount_t);
+
projects / apple / xnu.git / blobdiff