[PATCH 6.10 158/375] cifs: Fix copy offload to flush destination region

[PATCH 6.10 158/375] cifs: Fix copy offload to flush destination region

[Greg Kroah-Hartman]

6.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Howells <dhowells@redhat.com>

[ Upstream commit 8101d6e112e2524e967368f920c404ae445a9757 ]

Fix cifs_file_copychunk_range() to flush the destination region before
invalidating it to avoid potential loss of data should the copy fail, in
whole or in part, in some way.

Fixes: 7b2404a886f8 ("cifs: Fix flushing, invalidation and file size with copy_file_range()")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Matthew Wilcox <willy@infradead.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/client/cifsfs.c | 21 ++++-----------------
 1 file changed, 4 insertions(+), 17 deletions(-)

diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c
index 2c4b357d85e2..a1acf5bd1e3a 100644
--- a/fs/smb/client/cifsfs.c
+++ b/fs/smb/client/cifsfs.c
@@ -1341,7 +1341,6 @@ ssize_t cifs_file_copychunk_range(unsigned int xid,
 	struct cifsFileInfo *smb_file_target;
 	struct cifs_tcon *src_tcon;
 	struct cifs_tcon *target_tcon;
-	unsigned long long destend, fstart, fend;
 	ssize_t rc;
 
 	cifs_dbg(FYI, "copychunk range\n");
@@ -1391,25 +1390,13 @@ ssize_t cifs_file_copychunk_range(unsigned int xid,
 			goto unlock;
 	}
 
-	destend = destoff + len - 1;
-
-	/* Flush the folios at either end of the destination range to prevent
-	 * accidental loss of dirty data outside of the range.
+	/* Flush and invalidate all the folios in the destination region.  If
+	 * the copy was successful, then some of the flush is extra overhead,
+	 * but we need to allow for the copy failing in some way (eg. ENOSPC).
 	 */
-	fstart = destoff;
-	fend = destend;
-
-	rc = cifs_flush_folio(target_inode, destoff, &fstart, &fend, true);
+	rc = filemap_invalidate_inode(target_inode, true, destoff, destoff + len - 1);
 	if (rc)
 		goto unlock;
-	rc = cifs_flush_folio(target_inode, destend, &fstart, &fend, false);
-	if (rc)
-		goto unlock;
-	if (fend > target_cifsi->netfs.zero_point)
-		target_cifsi->netfs.zero_point = fend + 1;
-
-	/* Discard all the folios that overlap the destination region. */
-	truncate_inode_pages_range(&target_inode->i_data, fstart, fend);
 
 	fscache_invalidate(cifs_inode_cookie(target_inode), NULL,
 			   i_size_read(target_inode), 0);
-- 
2.43.0

[PATCH 6.10 159/375] cifs: Fix FALLOC_FL_ZERO_RANGE to preflush buffered part of target region

[Greg Kroah-Hartman]

6.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Howells <dhowells@redhat.com>

[ Upstream commit 91d1dfae464987aaf6c79ff51d8674880fb3be77 ]

Under certain conditions, the range to be cleared by FALLOC_FL_ZERO_RANGE
may only be buffered locally and not yet have been flushed to the server.
For example:

	xfs_io -f -t -c "pwrite -S 0x41 0 4k" \
		     -c "pwrite -S 0x42 4k 4k" \
		     -c "fzero 0 4k" \
		     -c "pread -v 0 8k" /xfstest.test/foo

will write two 4KiB blocks of data, which get buffered in the pagecache,
and then fallocate() is used to clear the first 4KiB block on the server -
but we don't flush the data first, which means the EOF position on the
server is wrong, and so the FSCTL_SET_ZERO_DATA RPC fails (and xfs_io
ignores the error), but then when we try to read it, we see the old data.

Fix this by preflushing any part of the target region that above the
server's idea of the EOF position to force the server to update its EOF
position.

Note, however, that we don't want to simply expand the file by moving the
EOF before doing the FSCTL_SET_ZERO_DATA[*] because someone else might see
the zeroed region or if the RPC fails we then have to try to clean it up or
risk getting corruption.

[*] And we have to move the EOF first otherwise FSCTL_SET_ZERO_DATA won't
do what we want.

This fixes the generic/008 xfstest.

[!] Note: A better way to do this might be to split the operation into two
parts: we only do FSCTL_SET_ZERO_DATA for the part of the range below the
server's EOF and then, if that worked, invalidate the buffered pages for the
part above the range.

Fixes: 6b69040247e1 ("cifs/smb3: Fix data inconsistent when zero file range")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.com>
cc: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
cc: Pavel Shilovsky <pshilov@microsoft.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/client/smb2ops.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 42352f70b01c..1d6e8eacdd74 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -3219,13 +3219,15 @@ static long smb3_zero_data(struct file *file, struct cifs_tcon *tcon,
 }
 
 static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
-			    loff_t offset, loff_t len, bool keep_size)
+			    unsigned long long offset, unsigned long long len,
+			    bool keep_size)
 {
 	struct cifs_ses *ses = tcon->ses;
 	struct inode *inode = file_inode(file);
 	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 	struct cifsFileInfo *cfile = file->private_data;
-	unsigned long long new_size;
+	struct netfs_inode *ictx = netfs_inode(inode);
+	unsigned long long i_size, new_size, remote_size;
 	long rc;
 	unsigned int xid;
 
@@ -3237,6 +3239,16 @@ static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
 	inode_lock(inode);
 	filemap_invalidate_lock(inode->i_mapping);
 
+	i_size = i_size_read(inode);
+	remote_size = ictx->remote_i_size;
+	if (offset + len >= remote_size && offset < i_size) {
+		unsigned long long top = umin(offset + len, i_size);
+
+		rc = filemap_write_and_wait_range(inode->i_mapping, offset, top - 1);
+		if (rc < 0)
+			goto zero_range_exit;
+	}
+
 	/*
 	 * We zero the range through ioctl, so we need remove the page caches
 	 * first, otherwise the data may be inconsistent with the server.
-- 
2.43.0

[PATCH 6.10 363/375] cifs: Fix zero_point init on inode initialisation

[Greg Kroah-Hartman]

6.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Howells <dhowells@redhat.com>

[ Upstream commit 517b58c1f9242a6b4ac9443d95569dee58bf6b8b ]

Fix cifs_fattr_to_inode() such that the ->zero_point tracking variable
is initialised when the inode is initialised.

Fixes: 3ee1a1fc3981 ("cifs: Cut over to using netfslib")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/smb/client/inode.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/smb/client/inode.c b/fs/smb/client/inode.c
index dd0afa23734c..73e2e6c230b7 100644
--- a/fs/smb/client/inode.c
+++ b/fs/smb/client/inode.c
@@ -172,6 +172,8 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr,
 		CIFS_I(inode)->time = 0; /* force reval */
 		return -ESTALE;
 	}
+	if (inode->i_state & I_NEW)
+		CIFS_I(inode)->netfs.zero_point = fattr->cf_eof;
 
 	cifs_revalidate_cache(inode, fattr);
 
-- 
2.43.0