nfs42: respect clone_blksize
draft-ietf-nfsv4-minorversion2-38.txt says:
Both cl_src_offset and
cl_dst_offset must be aligned to the clone block size Section 12.2.1.
The number of bytes to be cloned must be a multiple of the clone
block size, except in the case in which cl_src_offset plus the number
of bytes to be cloned is equal to the source file size.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index fc68ba5..4f463dd 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -199,8 +199,10 @@
u64 src_off, u64 dst_off, u64 count)
{
struct inode *dst_inode = file_inode(dst_file);
+ struct nfs_server *server = NFS_SERVER(dst_inode);
struct fd src_file;
struct inode *src_inode;
+ unsigned int bs = server->clone_blksize;
int ret;
/* dst file must be opened for writing */
@@ -238,6 +240,15 @@
src_inode->i_sb != dst_inode->i_sb)
goto out_fput;
+ /* check alignment w.r.t. clone_blksize */
+ ret = -EINVAL;
+ if (bs) {
+ if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
+ goto out_fput;
+ if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
+ goto out_fput;
+ }
+
/* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
if (dst_inode < src_inode) {
mutex_lock_nested(&dst_inode->i_mutex, I_MUTEX_PARENT);