9p: Fix a bunch of kerneldoc warnings shown up by W=1

Fix a bunch of kerneldoc warnings shown up by W=1 in the 9p filesystem:

 (1) Add/remove/fix kerneldoc parameters descriptions.

 (2) Move __add_fid() from between v9fs_fid_add() and its comment.

 (3) 9p's caches_show() doesn't really make sense as an API function, so
     remove the kerneldoc annotation.  It's also not prefixed with 'v9fs_'.
     Also remove the kerneldoc markers from the 9p fscache wrappers.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Mauro Carvalho Chehab <mchehab@kernel.org>
cc: v9fs-developer@lists.sourceforge.net
cc: linux-fsdevel@vger.kernel.org
cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/163214005516.2945267.7000234432243167892.stgit@warthog.procyon.org.uk/ # rfc v1
Link: https://lore.kernel.org/r/163281899704.2790286.9177774252843775348.stgit@warthog.procyon.org.uk/ # rfc v2
diff --git a/fs/9p/cache.c b/fs/9p/cache.c
index eb2151f..1769a44 100644
--- a/fs/9p/cache.c
+++ b/fs/9p/cache.c
@@ -23,7 +23,7 @@ struct fscache_netfs v9fs_cache_netfs = {
 	.version 	= 0,
 };
 
-/**
+/*
  * v9fs_random_cachetag - Generate a random tag to be associated
  *			  with a new cache session.
  *
@@ -233,7 +233,7 @@ static void v9fs_vfs_readpage_complete(struct page *page, void *data,
 	unlock_page(page);
 }
 
-/**
+/*
  * __v9fs_readpage_from_fscache - read a page from cache
  *
  * Returns 0 if the pages are in cache and a BIO is submitted,
@@ -268,7 +268,7 @@ int __v9fs_readpage_from_fscache(struct inode *inode, struct page *page)
 	}
 }
 
-/**
+/*
  * __v9fs_readpages_from_fscache - read multiple pages from cache
  *
  * Returns 0 if the pages are in cache and a BIO is submitted,
@@ -308,7 +308,7 @@ int __v9fs_readpages_from_fscache(struct inode *inode,
 	}
 }
 
-/**
+/*
  * __v9fs_readpage_to_fscache - write a page to the cache
  *
  */
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index 9d9de62..b8863dd 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -19,18 +19,18 @@
 #include "v9fs_vfs.h"
 #include "fid.h"
 
+static inline void __add_fid(struct dentry *dentry, struct p9_fid *fid)
+{
+	hlist_add_head(&fid->dlist, (struct hlist_head *)&dentry->d_fsdata);
+}
+
+
 /**
  * v9fs_fid_add - add a fid to a dentry
  * @dentry: dentry that the fid is being added to
  * @fid: fid to add
  *
  */
-
-static inline void __add_fid(struct dentry *dentry, struct p9_fid *fid)
-{
-	hlist_add_head(&fid->dlist, (struct hlist_head *)&dentry->d_fsdata);
-}
-
 void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
 {
 	spin_lock(&dentry->d_lock);
@@ -67,7 +67,7 @@ static struct p9_fid *v9fs_fid_find_inode(struct inode *inode, kuid_t uid)
 
 /**
  * v9fs_open_fid_add - add an open fid to an inode
- * @dentry: inode that the fid is being added to
+ * @inode: inode that the fid is being added to
  * @fid: fid to add
  *
  */
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index cdb9950..2e0fa7c 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -155,6 +155,7 @@ int v9fs_show_options(struct seq_file *m, struct dentry *root)
 /**
  * v9fs_parse_options - parse mount options into session structure
  * @v9ses: existing v9fs session information
+ * @opts: The mount option string
  *
  * Return 0 upon success, -ERRNO upon failure.
  */
@@ -542,12 +543,9 @@ extern int v9fs_error_init(void);
 static struct kobject *v9fs_kobj;
 
 #ifdef CONFIG_9P_FSCACHE
-/**
- * caches_show - list caches associated with a session
- *
- * Returns the size of buffer written.
+/*
+ * List caches associated with a session
  */
-
 static ssize_t caches_show(struct kobject *kobj,
 			   struct kobj_attribute *attr,
 			   char *buf)
diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
index cce9ace..1c4f1b3 100644
--- a/fs/9p/vfs_addr.c
+++ b/fs/9p/vfs_addr.c
@@ -30,8 +30,7 @@
 
 /**
  * v9fs_fid_readpage - read an entire page in from 9P
- *
- * @fid: fid being read
+ * @data: Opaque pointer to the fid being read
  * @page: structure to page
  *
  */
@@ -116,6 +115,8 @@ static int v9fs_vfs_readpages(struct file *filp, struct address_space *mapping,
 
 /**
  * v9fs_release_page - release the private state associated with a page
+ * @page: The page to be released
+ * @gfp: The caller's allocation restrictions
  *
  * Returns 1 if the page can be released, false otherwise.
  */
@@ -129,9 +130,9 @@ static int v9fs_release_page(struct page *page, gfp_t gfp)
 
 /**
  * v9fs_invalidate_page - Invalidate a page completely or partially
- *
- * @page: structure to page
- * @offset: offset in the page
+ * @page: The page to be invalidated
+ * @offset: offset of the invalidated region
+ * @length: length of the invalidated region
  */
 
 static void v9fs_invalidate_page(struct page *page, unsigned int offset,
@@ -199,6 +200,8 @@ static int v9fs_vfs_writepage(struct page *page, struct writeback_control *wbc)
 
 /**
  * v9fs_launder_page - Writeback a dirty page
+ * @page: The page to be cleaned up
+ *
  * Returns 0 on success.
  */
 
@@ -219,6 +222,7 @@ static int v9fs_launder_page(struct page *page)
 /**
  * v9fs_direct_IO - 9P address space operation for direct I/O
  * @iocb: target I/O control block
+ * @iter: The data/buffer to use
  *
  * The presence of v9fs_direct_IO() in the address space ops vector
  * allowes open() O_DIRECT flags which would have failed otherwise.
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index aab5e65..246235e 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -359,14 +359,11 @@ static int v9fs_file_flock_dotl(struct file *filp, int cmd,
 }
 
 /**
- * v9fs_file_read - read from a file
- * @filp: file pointer to read
- * @udata: user data buffer to read data into
- * @count: size of buffer
- * @offset: offset at which to read data
+ * v9fs_file_read_iter - read from a file
+ * @iocb: The operation parameters
+ * @to: The buffer to read into
  *
  */
-
 static ssize_t
 v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
@@ -388,11 +385,9 @@ v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 }
 
 /**
- * v9fs_file_write - write to a file
- * @filp: file pointer to write
- * @data: data buffer to write data from
- * @count: size of buffer
- * @offset: offset at which to write data
+ * v9fs_file_write_iter - write to a file
+ * @iocb: The operation parameters
+ * @from: The data to write
  *
  */
 static ssize_t
@@ -561,11 +556,9 @@ v9fs_vm_page_mkwrite(struct vm_fault *vmf)
 }
 
 /**
- * v9fs_mmap_file_read - read from a file
- * @filp: file pointer to read
- * @data: user data buffer to read data into
- * @count: size of buffer
- * @offset: offset at which to read data
+ * v9fs_mmap_file_read_iter - read from a file
+ * @iocb: The operation parameters
+ * @to: The buffer to read into
  *
  */
 static ssize_t
@@ -576,11 +569,9 @@ v9fs_mmap_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 }
 
 /**
- * v9fs_mmap_file_write - write to a file
- * @filp: file pointer to write
- * @data: data buffer to write data from
- * @count: size of buffer
- * @offset: offset at which to write data
+ * v9fs_mmap_file_write_iter - write to a file
+ * @iocb: The operation parameters
+ * @from: The data to write
  *
  */
 static ssize_t
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 7957065..08f48b7 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -218,7 +218,7 @@ v9fs_blank_wstat(struct p9_wstat *wstat)
 
 /**
  * v9fs_alloc_inode - helper function to allocate an inode
- *
+ * @sb: The superblock to allocate the inode from
  */
 struct inode *v9fs_alloc_inode(struct super_block *sb)
 {
@@ -238,7 +238,7 @@ struct inode *v9fs_alloc_inode(struct super_block *sb)
 
 /**
  * v9fs_free_inode - destroy an inode
- *
+ * @inode: The inode to be freed
  */
 
 void v9fs_free_inode(struct inode *inode)
@@ -343,7 +343,7 @@ int v9fs_init_inode(struct v9fs_session_info *v9ses,
  * v9fs_get_inode - helper function to setup an inode
  * @sb: superblock
  * @mode: mode to setup inode with
- *
+ * @rdev: The device numbers to set
  */
 
 struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev)
@@ -369,7 +369,7 @@ struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev)
 }
 
 /**
- * v9fs_clear_inode - release an inode
+ * v9fs_evict_inode - Remove an inode from the inode cache
  * @inode: inode to release
  *
  */
@@ -665,14 +665,15 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 
 /**
  * v9fs_vfs_create - VFS hook to create a regular file
+ * @mnt_userns: The user namespace of the mount
+ * @dir: The parent directory
+ * @dentry: The name of file to be created
+ * @mode: The UNIX file mode to set
+ * @excl: True if the file must not yet exist
  *
  * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open().  This is only called
  * for mknod(2).
  *
- * @dir: directory inode that is being created
- * @dentry:  dentry that is being deleted
- * @mode: create permissions
- *
  */
 
 static int
@@ -696,6 +697,7 @@ v9fs_vfs_create(struct user_namespace *mnt_userns, struct inode *dir,
 
 /**
  * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
+ * @mnt_userns: The user namespace of the mount
  * @dir:  inode that is being unlinked
  * @dentry: dentry that is being unlinked
  * @mode: mode for new directory
@@ -900,10 +902,12 @@ int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
 
 /**
  * v9fs_vfs_rename - VFS hook to rename an inode
+ * @mnt_userns: The user namespace of the mount
  * @old_dir:  old dir inode
  * @old_dentry: old dentry
  * @new_dir: new dir inode
  * @new_dentry: new dentry
+ * @flags: RENAME_* flags
  *
  */
 
@@ -1009,6 +1013,7 @@ v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
 
 /**
  * v9fs_vfs_getattr - retrieve file metadata
+ * @mnt_userns: The user namespace of the mount
  * @path: Object to query
  * @stat: metadata structure to populate
  * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
@@ -1050,6 +1055,7 @@ v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
 
 /**
  * v9fs_vfs_setattr - set file metadata
+ * @mnt_userns: The user namespace of the mount
  * @dentry: file whose metadata to set
  * @iattr: metadata assignment structure
  *
@@ -1285,6 +1291,7 @@ static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
 
 /**
  * v9fs_vfs_symlink - helper function to create symlinks
+ * @mnt_userns: The user namespace of the mount
  * @dir: directory inode containing symlink
  * @dentry: dentry for symlink
  * @symname: symlink data
@@ -1340,6 +1347,7 @@ v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
 
 /**
  * v9fs_vfs_mknod - create a special file
+ * @mnt_userns: The user namespace of the mount
  * @dir: inode destination for new link
  * @dentry: dentry for file
  * @mode: mode for creation
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index e1c0240..01b9e12 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -37,7 +37,10 @@ v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
 		    struct dentry *dentry, umode_t omode, dev_t rdev);
 
 /**
- * v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
+ * v9fs_get_fsgid_for_create - Helper function to get the gid for a new object
+ * @dir_inode: The directory inode
+ *
+ * Helper function to get the gid for creating a
  * new file system object. This checks the S_ISGID to determine the owning
  * group of the new file system object.
  */
@@ -211,12 +214,13 @@ int v9fs_open_to_dotl_flags(int flags)
 
 /**
  * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
+ * @mnt_userns: The user namespace of the mount
  * @dir: directory inode that is being created
  * @dentry:  dentry that is being deleted
  * @omode: create permissions
+ * @excl: True if the file must not yet exist
  *
  */
-
 static int
 v9fs_vfs_create_dotl(struct user_namespace *mnt_userns, struct inode *dir,
 		     struct dentry *dentry, umode_t omode, bool excl)
@@ -361,6 +365,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 
 /**
  * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
+ * @mnt_userns: The user namespace of the mount
  * @dir:  inode that is being unlinked
  * @dentry: dentry that is being unlinked
  * @omode: mode for new directory
@@ -537,6 +542,7 @@ static int v9fs_mapped_iattr_valid(int iattr_valid)
 
 /**
  * v9fs_vfs_setattr_dotl - set file metadata
+ * @mnt_userns: The user namespace of the mount
  * @dentry: file whose metadata to set
  * @iattr: metadata assignment structure
  *
@@ -816,6 +822,7 @@ v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
 
 /**
  * v9fs_vfs_mknod_dotl - create a special file
+ * @mnt_userns: The user namespace of the mount
  * @dir: inode destination for new link
  * @dentry: dentry for file
  * @omode: mode for creation