fs/netfs: remove unused flag NETFS_ICTX_WRITETHROUGH

This flag was added by commit 41d8e76 ("netfs: Implement a
write-through caching option") but it was never used.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-5-dhowells@redhat.com
cc: Paulo Alcantara <pc@manguebit.com>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: MaxKellermann

fs/netfs/buffered_write.c

@@ -115,8 +115,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
 	size_t max_chunk = mapping_max_folio_size(mapping);
 	bool maybe_trouble = false;
 
-	if (unlikely(test_bit(NETFS_ICTX_WRITETHROUGH, &ctx->flags) ||
-		     iocb->ki_flags & (IOCB_DSYNC | IOCB_SYNC))
+	if (unlikely(iocb->ki_flags & (IOCB_DSYNC | IOCB_SYNC))
 	    ) {
 		wbc_attach_fdatawrite_inode(&wbc, mapping->host);
 

include/linux/netfs.h

@@ -70,7 +70,6 @@ struct netfs_inode {
 	unsigned long		flags;
 #define NETFS_ICTX_ODIRECT	0		/* The file has DIO in progress */
 #define NETFS_ICTX_UNBUFFERED	1		/* I/O should not use the pagecache */
-#define NETFS_ICTX_WRITETHROUGH	2		/* Write-through caching */
 #define NETFS_ICTX_MODIFIED_ATTR 3		/* Indicate change in mtime/ctime */
 #define NETFS_ICTX_SINGLE_NO_UPLOAD 4		/* Monolithic payload, cache but no upload */
 };