netfs: Further cleanups after struct netfs_inode wrapper introduced

Change the signature of netfs helper functions to take a struct netfs_inode
pointer rather than a struct inode pointer where appropriate, thereby
relieving the need for the network filesystem to convert its internal inode
format down to the VFS inode only for netfslib to bounce it back up.  For
type safety, it's better not to do that (and it's less typing too).

Give netfs_write_begin() an extra argument to pass in a pointer to the
netfs_inode struct rather than deriving it internally from the file
pointer.  Note that the ->write_begin() and ->write_end() ops are intended
to be replaced in the future by netfslib code that manages this without the
need to call in twice for each page.

netfs_readpage() and similar are intended to be pointed at directly by the
address_space_operations table, so must stick to the signature dictated by
the function pointers there.

Changes
=======
- Updated the kerneldoc comments and documentation [DH].

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/CAHk-=wgkwKyNmNdKpQkqZ6DnmUL-x9hp0YBnUGjaPFEAdxDTbw@mail.gmail.com/

1 files changed, 3 insertions, 2 deletions

diff --git a/fs/netfs/buffered_read.c b/fs/netfs/buffered_read.c
index d37e012386f3..42f892c5712e 100644
--- a/fs/netfs/buffered_read.c
+++ b/fs/netfs/buffered_read.c
@@ -297,6 +297,7 @@ zero_out:
 
 /**
  * netfs_write_begin - Helper to prepare for writing
+ * @ctx: The netfs context
  * @file: The file to read from
  * @mapping: The mapping to read from
  * @pos: File position at which the write will begin
@@ -326,12 +327,12 @@ zero_out:
  *
  * This is usable whether or not caching is enabled.
  */
-int netfs_write_begin(struct file *file, struct address_space *mapping,
+int netfs_write_begin(struct netfs_inode *ctx,
+		      struct file *file, struct address_space *mapping,
 		      loff_t pos, unsigned int len, struct folio **_folio,
 		      void **_fsdata)
 {
 	struct netfs_io_request *rreq;
-	struct netfs_inode *ctx = netfs_inode(file_inode(file ));
 	struct folio *folio;
 	unsigned int fgp_flags = FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE;
 	pgoff_t index = pos >> PAGE_SHIFT;