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-rw-r--r--include/linux/fs.h100
1 files changed, 52 insertions, 48 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 3f825b0..4edba06 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1065,71 +1065,75 @@ int sync_inode(struct inode *inode, struct writeback_control *wbc);
* with a particular exported file system - particularly enabling nfsd and
* the filesystem to co-operate when dealing with file handles.
*
- * export_operations contains two basic operation for dealing with file handles,
- * decode_fh() and encode_fh(), and allows for some other operations to be defined
- * which standard helper routines use to get specific information from the
- * filesystem.
+ * export_operations contains two basic operation for dealing with file
+ * handles, decode_fh() and encode_fh(), and allows for some other
+ * operations to be defined which standard helper routines use to get
+ * specific information from the filesystem.
*
* nfsd encodes information use to determine which filesystem a filehandle
- * applies to in the initial part of the file handle. The remainder, termed a
- * file handle fragment, is controlled completely by the filesystem.
- * The standard helper routines assume that this fragment will contain one or two
- * sub-fragments, one which identifies the file, and one which may be used to
- * identify the (a) directory containing the file.
+ * applies to in the initial part of the file handle. The remainder, termed
+ * a file handle fragment, is controlled completely by the filesystem. The
+ * standard helper routines assume that this fragment will contain one or
+ * two sub-fragments, one which identifies the file, and one which may be
+ * used to identify the (a) directory containing the file.
*
* In some situations, nfsd needs to get a dentry which is connected into a
- * specific part of the file tree. To allow for this, it passes the function
- * acceptable() together with a @context which can be used to see if the dentry
- * is acceptable. As there can be multiple dentrys for a given file, the filesystem
- * should check each one for acceptability before looking for the next. As soon
- * as an acceptable one is found, it should be returned.
+ * specific part of the file tree. To allow for this, it passes the
+ * function acceptable() together with a @context which can be used to see
+ * if the dentry is acceptable. As there can be multiple dentrys for a
+ * given file, the filesystem should check each one for acceptability before
+ * looking for the next. As soon as an acceptable one is found, it should
+ * be returned.
*
* decode_fh:
- * @decode_fh is given a &struct super_block (@sb), a file handle fragment (@fh, @fh_len)
- * and an acceptability testing function (@acceptable, @context). It should return
- * a &struct dentry which refers to the same file that the file handle fragment refers
- * to, and which passes the acceptability test. If it cannot, it should return
- * a %NULL pointer if the file was found but no acceptable &dentries were available, or
- * a %ERR_PTR error code indicating why it couldn't be found (e.g. %ENOENT or %ENOMEM).
+ * @decode_fh is given a &struct super_block (@sb), a file handle fragment
+ * (@fh, @fh_len) and an acceptability testing function (@acceptable,
+ * @context). It should return a &struct dentry which refers to the same
+ * file that the file handle fragment refers to, and which passes the
+ * acceptability test. If it cannot, it should return a %NULL pointer if
+ * the file was found but no acceptable &dentries were available, or a
+ * %ERR_PTR error code indicating why it couldn't be found (e.g. %ENOENT or
+ * %ENOMEM).
*
* encode_fh:
- * @encode_fh should store in the file handle fragment @fh (using at most @max_len bytes)
- * information that can be used by @decode_fh to recover the file refered to by the
- * &struct dentry @de. If the @connectable flag is set, the encode_fh() should store
- * sufficient information so that a good attempt can be made to find not only
- * the file but also it's place in the filesystem. This typically means storing
- * a reference to de->d_parent in the filehandle fragment.
- * encode_fh() should return the number of bytes stored or a negative error code
- * such as %-ENOSPC
+ * @encode_fh should store in the file handle fragment @fh (using at most
+ * @max_len bytes) information that can be used by @decode_fh to recover the
+ * file refered to by the &struct dentry @de. If the @connectable flag is
+ * set, the encode_fh() should store sufficient information so that a good
+ * attempt can be made to find not only the file but also it's place in the
+ * filesystem. This typically means storing a reference to de->d_parent in
+ * the filehandle fragment. encode_fh() should return the number of bytes
+ * stored or a negative error code such as %-ENOSPC
*
* get_name:
- * @get_name should find a name for the given @child in the given @parent directory.
- * The name should be stored in the @name (with the understanding that it is already
- * pointing to a a %NAME_MAX+1 sized buffer. get_name() should return %0 on success,
- * a negative error code or error.
- * @get_name will be called without @parent->i_sem held.
+ * @get_name should find a name for the given @child in the given @parent
+ * directory. The name should be stored in the @name (with the
+ * understanding that it is already pointing to a a %NAME_MAX+1 sized
+ * buffer. get_name() should return %0 on success, a negative error code
+ * or error. @get_name will be called without @parent->i_sem held.
*
* get_parent:
- * @get_parent should find the parent directory for the given @child which is also
- * a directory. In the event that it cannot be found, or storage space cannot be
- * allocated, a %ERR_PTR should be returned.
+ * @get_parent should find the parent directory for the given @child which
+ * is also a directory. In the event that it cannot be found, or storage
+ * space cannot be allocated, a %ERR_PTR should be returned.
*
* get_dentry:
- * Given a &super_block (@sb) and a pointer to a file-system specific inode identifier,
- * possibly an inode number, (@inump) get_dentry() should find the identified inode and
- * return a dentry for that inode.
- * Any suitable dentry can be returned including, if necessary, a new dentry created
- * with d_alloc_root. The caller can then find any other extant dentrys by following the
- * d_alias links. If a new dentry was created using d_alloc_root, DCACHE_NFSD_DISCONNECTED
- * should be set, and the dentry should be d_rehash()ed.
+ * Given a &super_block (@sb) and a pointer to a file-system specific inode
+ * identifier, possibly an inode number, (@inump) get_dentry() should find
+ * the identified inode and return a dentry for that inode. Any suitable
+ * dentry can be returned including, if necessary, a new dentry created with
+ * d_alloc_root. The caller can then find any other extant dentrys by
+ * following the d_alias links. If a new dentry was created using
+ * d_alloc_root, DCACHE_NFSD_DISCONNECTED should be set, and the dentry
+ * should be d_rehash()ed.
*
- * If the inode cannot be found, either a %NULL pointer or an %ERR_PTR code can be returned.
- * The @inump will be whatever was passed to nfsd_find_fh_dentry() in either the
- * @obj or @parent parameters.
+ * If the inode cannot be found, either a %NULL pointer or an %ERR_PTR code
+ * can be returned. The @inump will be whatever was passed to
+ * nfsd_find_fh_dentry() in either the @obj or @parent parameters.
*
* Locking rules:
- * get_parent is called with child->d_inode->i_sem down
- * get_name is not (which is possibly inconsistent)
+ * get_parent is called with child->d_inode->i_sem down
+ * get_name is not (which is possibly inconsistent)
*/
struct export_operations {
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