FAILED: patch "[PATCH] cifs: Fix FALLOC_FL_ZERO_RANGE by setting i_size if EOF moved" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 83d5518b124dfd605f10a68128482c839a239f9d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023120341-floss-starring-3167@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

83d5518b124d ("cifs: Fix FALLOC_FL_ZERO_RANGE by setting i_size if EOF moved") 38c8a9a52082 ("smb: move client and server files to common directory fs/smb") abdb1742a312 ("cifs: get rid of mount options string parsing")
9fd29a5bae6e ("cifs: use fs_context for automounts")
c919c164fc87 ("smb3: missing inode locks in zero range")
400d0ad63b19 ("cifs: remove useless parameter 'is_fsctl' from SMB2_ioctl()") 5dd8ce24667a ("cifs: missing directory in MAINTAINERS file")
332019e23a51 ("Merge tag '5.20-rc-smb3-client-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 83d5518b124dfd605f10a68128482c839a239f9d Mon Sep 17 00:00:00 2001
From: David Howells <[email protected]>
Date: Wed, 29 Nov 2023 16:56:17 +0000
Subject: [PATCH] cifs: Fix FALLOC_FL_ZERO_RANGE by setting i_size if EOF moved

Fix the cifs filesystem implementations of FALLOC_FL_ZERO_RANGE, in smb3_zero_range(), to set i_size after extending the file on the server.

index 82ab62fd0040..f1b0b2b11ab2 100644
@@ -3311,6 +3311,7 @@ static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
 	struct inode *inode = file_inode(file);
 	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 	struct cifsFileInfo *cfile = file->private_data;
+	unsigned long long new_size;
 	long rc;
 	unsigned int xid;
 	__le64 eof;

@@ -3341,10 +3342,15 @@ static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
 	/*
 	 * do we also need to change the size of the file?
 	 */
-	if (keep_size == false && i_size_read(inode) < offset + len) {
-		eof = cpu_to_le64(offset + len);
+	new_size = offset + len;
+	if (keep_size == false && (unsigned long long)i_size_read(inode) < new_size) {
+		eof = cpu_to_le64(new_size);
 		rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
 				  cfile->fid.volatile_fid, cfile->pid, &eof);
+		if (rc >= 0) {
+			truncate_setsize(inode, new_size);
+			fscache_resize_cookie(cifs_inode_cookie(inode), new_size);
+		}
 	}
 
  zero_range_exit: