[PATCH v19 08/15] cifs: Use generic_file_splice_read()

[David Howells <dhowells@redhat.com>]

Make cifs use generic_file_splice_read() rather than doing it for itself.

As a consequence, filemap_splice_read() no longer needs to be exported.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: Steve French <smfrench@gmail.com>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: David Hildenbrand <david@redhat.com>
cc: John Hubbard <jhubbard@nvidia.com>
cc: linux-mm@kvack.org
cc: linux-block@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
---

Notes:
    ver #18)
     - Split out from change to generic_file_splice_read().

 fs/cifs/cifsfs.c |  8 ++++----
 fs/cifs/cifsfs.h |  3 ---
 fs/cifs/file.c   | 16 ----------------
 mm/filemap.c     |  1 -
 4 files changed, 4 insertions(+), 24 deletions(-)

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index cbcf210d56e4..ba963a26cb19 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1359,7 +1359,7 @@ const struct file_operations cifs_file_ops = {
 	.fsync = cifs_fsync,
 	.flush = cifs_flush,
 	.mmap  = cifs_file_mmap,
-	.splice_read = cifs_splice_read,
+	.splice_read = generic_file_splice_read,
 	.splice_write = iter_file_splice_write,
 	.llseek = cifs_llseek,
 	.unlocked_ioctl	= cifs_ioctl,
@@ -1379,7 +1379,7 @@ const struct file_operations cifs_file_strict_ops = {
 	.fsync = cifs_strict_fsync,
 	.flush = cifs_flush,
 	.mmap = cifs_file_strict_mmap,
-	.splice_read = cifs_splice_read,
+	.splice_read = generic_file_splice_read,
 	.splice_write = iter_file_splice_write,
 	.llseek = cifs_llseek,
 	.unlocked_ioctl	= cifs_ioctl,
@@ -1417,7 +1417,7 @@ const struct file_operations cifs_file_nobrl_ops = {
 	.fsync = cifs_fsync,
 	.flush = cifs_flush,
 	.mmap  = cifs_file_mmap,
-	.splice_read = cifs_splice_read,
+	.splice_read = generic_file_splice_read,
 	.splice_write = iter_file_splice_write,
 	.llseek = cifs_llseek,
 	.unlocked_ioctl	= cifs_ioctl,
@@ -1435,7 +1435,7 @@ const struct file_operations cifs_file_strict_nobrl_ops = {
 	.fsync = cifs_strict_fsync,
 	.flush = cifs_flush,
 	.mmap = cifs_file_strict_mmap,
-	.splice_read = cifs_splice_read,
+	.splice_read = generic_file_splice_read,
 	.splice_write = iter_file_splice_write,
 	.llseek = cifs_llseek,
 	.unlocked_ioctl	= cifs_ioctl,
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 71fe0a0a7992..8b239854e590 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -100,9 +100,6 @@ extern ssize_t cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to);
 extern ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from);
 extern ssize_t cifs_direct_writev(struct kiocb *iocb, struct iov_iter *from);
 extern ssize_t cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from);
-extern ssize_t cifs_splice_read(struct file *in, loff_t *ppos,
-				struct pipe_inode_info *pipe, size_t len,
-				unsigned int flags);
 extern int cifs_flock(struct file *pfile, int cmd, struct file_lock *plock);
 extern int cifs_lock(struct file *, int, struct file_lock *);
 extern int cifs_fsync(struct file *, loff_t, loff_t, int);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 4d4a2d82636d..321f9b7c84c9 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -5066,19 +5066,3 @@ const struct address_space_operations cifs_addr_ops_smallbuf = {
 	.launder_folio = cifs_launder_folio,
 	.migrate_folio = filemap_migrate_folio,
 };
-
-/*
- * Splice data from a file into a pipe.
- */
-ssize_t cifs_splice_read(struct file *in, loff_t *ppos,
-			 struct pipe_inode_info *pipe, size_t len,
-			 unsigned int flags)
-{
-	if (unlikely(*ppos >= file_inode(in)->i_sb->s_maxbytes))
-		return 0;
-	if (unlikely(!len))
-		return 0;
-	if (in->f_flags & O_DIRECT)
-		return direct_splice_read(in, ppos, pipe, len, flags);
-	return filemap_splice_read(in, ppos, pipe, len, flags);
-}
diff --git a/mm/filemap.c b/mm/filemap.c
index 2723104cc06a..3a93515ae2ed 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2967,7 +2967,6 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos,
 
 	return total_spliced ? total_spliced : error;
 }
-EXPORT_SYMBOL(filemap_splice_read);
 
 static inline loff_t folio_seek_hole_data(struct xa_state *xas,
 		struct address_space *mapping, struct folio *folio,