netfs, cifs: Move CIFS_INO_MODIFIED_ATTR to netfs_inode

Move CIFS_INO_MODIFIED_ATTR to netfs_inode as NETFS_ICTX_MODIFIED_ATTR and
then make netfs_perform_write() set it.  This means that cifs doesn't need
to implement the ->post_modify() hook.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20240814203850.2240469-7-dhowells@redhat.com/ # v2
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/netfs/buffered_write.c

@@ -372,8 +372,14 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
 	} while (iov_iter_count(iter));
 
 out:
-	if (likely(written) && ctx->ops->post_modify)
-		ctx->ops->post_modify(inode);
+	if (likely(written)) {
+		/* Set indication that ctime and mtime got updated in case
+		 * close is deferred.
+		 */
+		set_bit(NETFS_ICTX_MODIFIED_ATTR, &ctx->flags);
+		if (unlikely(ctx->ops->post_modify))
+			ctx->ops->post_modify(inode);
+	}
 
 	if (unlikely(wreq)) {
 		ret2 = netfs_end_writethrough(wreq, &wbc, writethrough);

fs/smb/client/cifsglob.h

@@ -1550,7 +1550,6 @@ struct cifsInodeInfo {
 #define CIFS_INO_DELETE_PENDING		  (3) /* delete pending on server */
 #define CIFS_INO_INVALID_MAPPING	  (4) /* pagecache is invalid */
 #define CIFS_INO_LOCK			  (5) /* lock bit for synchronization */
-#define CIFS_INO_MODIFIED_ATTR            (6) /* Indicate change in mtime/ctime */
 #define CIFS_INO_CLOSE_ON_LOCK            (7) /* Not to defer the close when lock is set */
 	unsigned long flags;
 	spinlock_t writers_lock;

fs/smb/client/file.c

@@ -316,12 +316,6 @@ static void cifs_rreq_done(struct netfs_io_request *rreq)
 		inode_set_atime_to_ts(inode, inode_get_mtime(inode));
 }
 
-static void cifs_post_modify(struct inode *inode)
-{
-	/* Indication to update ctime and mtime as close is deferred */
-	set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
-}
-
 static void cifs_free_request(struct netfs_io_request *rreq)
 {
 	struct cifs_io_request *req = container_of(rreq, struct cifs_io_request, rreq);
@@ -372,7 +366,6 @@ const struct netfs_request_ops cifs_req_ops = {
 	.clamp_length		= cifs_clamp_length,
 	.issue_read		= cifs_req_issue_read,
 	.done			= cifs_rreq_done,
-	.post_modify		= cifs_post_modify,
 	.begin_writeback	= cifs_begin_writeback,
 	.prepare_write		= cifs_prepare_write,
 	.issue_write		= cifs_issue_write,
@@ -1396,7 +1389,7 @@ int cifs_close(struct inode *inode, struct file *file)
 		dclose = kmalloc(sizeof(struct cifs_deferred_close), GFP_KERNEL);
 		if ((cfile->status_file_deleted == false) &&
 		    (smb2_can_defer_close(inode, dclose))) {
-			if (test_and_clear_bit(CIFS_INO_MODIFIED_ATTR, &cinode->flags)) {
+			if (test_and_clear_bit(NETFS_ICTX_MODIFIED_ATTR, &cinode->netfs.flags)) {
 				inode_set_mtime_to_ts(inode,
 						      inode_set_ctime_current(inode));
 			}

include/linux/netfs.h

@@ -73,6 +73,7 @@ struct netfs_inode {
 #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 */
 };
 
 /*