1 files changed, 162 insertions, 17 deletions

diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c
index ea3a7a668b45..99b0ade833aa 100644
--- a/fs/smb/client/cifsfs.c
+++ b/fs/smb/client/cifsfs.c
@@ -25,6 +25,7 @@
 #include <linux/freezer.h>
 #include <linux/namei.h>
 #include <linux/random.h>
+#include <linux/splice.h>
 #include <linux/uuid.h>
 #include <linux/xattr.h>
 #include <uapi/linux/magic.h>
@@ -1196,32 +1197,103 @@ const struct inode_operations cifs_symlink_inode_ops = {
 	.listxattr = cifs_listxattr,
 };
 
+/*
+ * Advance the EOF marker to after the source range.
+ */
+static int cifs_precopy_set_eof(struct inode *src_inode, struct cifsInodeInfo *src_cifsi,
+				struct cifs_tcon *src_tcon,
+				unsigned int xid, loff_t src_end)
+{
+	struct cifsFileInfo *writeable_srcfile;
+	int rc = -EINVAL;
+
+	writeable_srcfile = find_writable_file(src_cifsi, FIND_WR_FSUID_ONLY);
+	if (writeable_srcfile) {
+		if (src_tcon->ses->server->ops->set_file_size)
+			rc = src_tcon->ses->server->ops->set_file_size(
+				xid, src_tcon, writeable_srcfile,
+				src_inode->i_size, true /* no need to set sparse */);
+		else
+			rc = -ENOSYS;
+		cifsFileInfo_put(writeable_srcfile);
+		cifs_dbg(FYI, "SetFSize for copychunk rc = %d\n", rc);
+	}
+
+	if (rc < 0)
+		goto set_failed;
+
+	netfs_resize_file(&src_cifsi->netfs, src_end);
+	fscache_resize_cookie(cifs_inode_cookie(src_inode), src_end);
+	return 0;
+
+set_failed:
+	return filemap_write_and_wait(src_inode->i_mapping);
+}
+
+/*
+ * Flush out either the folio that overlaps the beginning of a range in which
+ * pos resides or the folio that overlaps the end of a range unless that folio
+ * is entirely within the range we're going to invalidate.  We extend the flush
+ * bounds to encompass the folio.
+ */
+static int cifs_flush_folio(struct inode *inode, loff_t pos, loff_t *_fstart, loff_t *_fend,
+			    bool first)
+{
+	struct folio *folio;
+	unsigned long long fpos, fend;
+	pgoff_t index = pos / PAGE_SIZE;
+	size_t size;
+	int rc = 0;
+
+	folio = filemap_get_folio(inode->i_mapping, index);
+	if (IS_ERR(folio))
+		return 0;
+
+	size = folio_size(folio);
+	fpos = folio_pos(folio);
+	fend = fpos + size - 1;
+	*_fstart = min_t(unsigned long long, *_fstart, fpos);
+	*_fend   = max_t(unsigned long long, *_fend, fend);
+	if ((first && pos == fpos) || (!first && pos == fend))
+		goto out;
+
+	rc = filemap_write_and_wait_range(inode->i_mapping, fpos, fend);
+out:
+	folio_put(folio);
+	return rc;
+}
+
 static loff_t cifs_remap_file_range(struct file *src_file, loff_t off,
 		struct file *dst_file, loff_t destoff, loff_t len,
 		unsigned int remap_flags)
 {
 	struct inode *src_inode = file_inode(src_file);
 	struct inode *target_inode = file_inode(dst_file);
+	struct cifsInodeInfo *src_cifsi = CIFS_I(src_inode);
+	struct cifsInodeInfo *target_cifsi = CIFS_I(target_inode);
 	struct cifsFileInfo *smb_file_src = src_file->private_data;
-	struct cifsFileInfo *smb_file_target;
-	struct cifs_tcon *target_tcon;
+	struct cifsFileInfo *smb_file_target = dst_file->private_data;
+	struct cifs_tcon *target_tcon, *src_tcon;
+	unsigned long long destend, fstart, fend, new_size;
 	unsigned int xid;
 	int rc;
 
-	if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
+	if (remap_flags & REMAP_FILE_DEDUP)
+		return -EOPNOTSUPP;
+	if (remap_flags & ~REMAP_FILE_ADVISORY)
 		return -EINVAL;
 
 	cifs_dbg(FYI, "clone range\n");
 
 	xid = get_xid();
 
-	if (!src_file->private_data || !dst_file->private_data) {
+	if (!smb_file_src || !smb_file_target) {
 		rc = -EBADF;
 		cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
 		goto out;
 	}
 
-	smb_file_target = dst_file->private_data;
+	src_tcon = tlink_tcon(smb_file_src->tlink);
 	target_tcon = tlink_tcon(smb_file_target->tlink);
 
 	/*
@@ -1234,20 +1306,63 @@ static loff_t cifs_remap_file_range(struct file *src_file, loff_t off,
 	if (len == 0)
 		len = src_inode->i_size - off;
 
-	cifs_dbg(FYI, "about to flush pages\n");
-	/* should we flush first and last page first */
-	truncate_inode_pages_range(&target_inode->i_data, destoff,
-				   PAGE_ALIGN(destoff + len)-1);
+	cifs_dbg(FYI, "clone range\n");
 
-	if (target_tcon->ses->server->ops->duplicate_extents)
+	/* Flush the source buffer */
+	rc = filemap_write_and_wait_range(src_inode->i_mapping, off,
+					  off + len - 1);
+	if (rc)
+		goto unlock;
+
+	/* The server-side copy will fail if the source crosses the EOF marker.
+	 * Advance the EOF marker after the flush above to the end of the range
+	 * if it's short of that.
+	 */
+	if (src_cifsi->netfs.remote_i_size < off + len) {
+		rc = cifs_precopy_set_eof(src_inode, src_cifsi, src_tcon, xid, off + len);
+		if (rc < 0)
+			goto unlock;
+	}
+
+	new_size = destoff + len;
+	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.
+	 */
+	fstart = destoff;
+	fend = destend;
+
+	rc = cifs_flush_folio(target_inode, destoff, &fstart, &fend, true);
+	if (rc)
+		goto unlock;
+	rc = cifs_flush_folio(target_inode, destend, &fstart, &fend, false);
+	if (rc)
+		goto unlock;
+
+	/* Discard all the folios that overlap the destination region. */
+	cifs_dbg(FYI, "about to discard pages %llx-%llx\n", fstart, fend);
+	truncate_inode_pages_range(&target_inode->i_data, fstart, fend);
+
+	fscache_invalidate(cifs_inode_cookie(target_inode), NULL,
+			   i_size_read(target_inode), 0);
+
+	rc = -EOPNOTSUPP;
+	if (target_tcon->ses->server->ops->duplicate_extents) {
 		rc = target_tcon->ses->server->ops->duplicate_extents(xid,
 			smb_file_src, smb_file_target, off, len, destoff);
-	else
-		rc = -EOPNOTSUPP;
+		if (rc == 0 && new_size > i_size_read(target_inode)) {
+			truncate_setsize(target_inode, new_size);
+			netfs_resize_file(&target_cifsi->netfs, new_size);
+			fscache_resize_cookie(cifs_inode_cookie(target_inode),
+					      new_size);
+		}
+	}
 
 	/* force revalidate of size and timestamps of target file now
 	   that target is updated on the server */
 	CIFS_I(target_inode)->time = 0;
+unlock:
 	/* although unlocking in the reverse order from locking is not
 	   strictly necessary here it is a little cleaner to be consistent */
 	unlock_two_nondirectories(src_inode, target_inode);
@@ -1263,10 +1378,12 @@ ssize_t cifs_file_copychunk_range(unsigned int xid,
 {
 	struct inode *src_inode = file_inode(src_file);
 	struct inode *target_inode = file_inode(dst_file);
+	struct cifsInodeInfo *src_cifsi = CIFS_I(src_inode);
 	struct cifsFileInfo *smb_file_src;
 	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");
@@ -1306,13 +1423,41 @@ ssize_t cifs_file_copychunk_range(unsigned int xid,
 	if (rc)
 		goto unlock;
 
-	/* should we flush first and last page first */
-	truncate_inode_pages(&target_inode->i_data, 0);
+	/* The server-side copy will fail if the source crosses the EOF marker.
+	 * Advance the EOF marker after the flush above to the end of the range
+	 * if it's short of that.
+	 */
+	if (src_cifsi->server_eof < off + len) {
+		rc = cifs_precopy_set_eof(src_inode, src_cifsi, src_tcon, xid, off + len);
+		if (rc < 0)
+			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.
+	 */
+	fstart = destoff;
+	fend = destend;
+
+	rc = cifs_flush_folio(target_inode, destoff, &fstart, &fend, true);
+	if (rc)
+		goto unlock;
+	rc = cifs_flush_folio(target_inode, destend, &fstart, &fend, false);
+	if (rc)
+		goto unlock;
+
+	/* Discard all the folios that overlap the destination region. */
+	truncate_inode_pages_range(&target_inode->i_data, fstart, fend);
 
 	rc = file_modified(dst_file);
-	if (!rc)
+	if (!rc) {
 		rc = target_tcon->ses->server->ops->copychunk_range(xid,
 			smb_file_src, smb_file_target, off, len, destoff);
+		if (rc > 0 && destoff + rc > i_size_read(target_inode))
+			truncate_setsize(target_inode, destoff + rc);
+	}
 
 	file_accessed(src_file);
 
@@ -1362,8 +1507,8 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off,
 	free_xid(xid);
 
 	if (rc == -EOPNOTSUPP || rc == -EXDEV)
-		rc = generic_copy_file_range(src_file, off, dst_file,
-					     destoff, len, flags);
+		rc = splice_copy_file_range(src_file, off, dst_file,
+					    destoff, len);
 	return rc;
 }