readlink: no
follow_link: no
put_link: no
-truncate: yes (see below)
setattr: yes
permission: no (may not block if called in rcu-walk mode)
get_acl: no
Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
victim.
cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
- ->truncate() is never called directly - it's a callback, not a
-method. It's called by vmtruncate() - deprecated library function used by
-->setattr(). Locking information above applies to that call (i.e. is
-inherited from ->setattr() - vmtruncate() is used when ATTR_SIZE had been
-passed).
See Documentation/filesystems/directory-locking for more detailed discussion
of the locking scheme for directory operations.
[mandatory]
- ->truncate is going away. The whole truncate sequence needs to be
+ ->truncate is gone. The whole truncate sequence needs to be
implemented in ->setattr, which is now mandatory for filesystems
implementing on-disk size changes. Start with a copy of the old inode_setattr
and vmtruncate, and the reorder the vmtruncate + foofs_vmtruncate sequence to
int (*readlink) (struct dentry *, char __user *,int);
void * (*follow_link) (struct dentry *, struct nameidata *);
void (*put_link) (struct dentry *, struct nameidata *, void *);
- void (*truncate) (struct inode *);
int (*permission) (struct inode *, int);
int (*get_acl)(struct inode *, int);
int (*setattr) (struct dentry *, struct iattr *);
started might not be in the page cache at the end of the
walk).
- truncate: Deprecated. This will not be called if ->setsize is defined.
- Called by the VFS to change the size of a file. The
- i_size field of the inode is set to the desired size by the
- VFS before this method is called. This method is called by
- the truncate(2) system call and related functionality.
-
- Note: ->truncate and vmtruncate are deprecated. Do not add new
- instances/calls of these. Filesystems should be converted to do their
- truncate sequence via ->setattr().
-
permission: called by the VFS to check for access rights on a POSIX-like
filesystem.