diff options
Diffstat (limited to 'fs/nfsd/vfs.c')
| -rw-r--r-- | fs/nfsd/vfs.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index ff476e654b8f..8ca642fe9b21 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -513,6 +513,22 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst, count)); } +ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst, + u64 dst_pos, u64 count) +{ + + /* + * Limit copy to 4MB to prevent indefinitely blocking an nfsd + * thread and client rpc slot. The choice of 4MB is somewhat + * arbitrary. We might instead base this on r/wsize, or make it + * tunable, or use a time instead of a byte limit, or implement + * asynchronous copy. In theory a client could also recognize a + * limit like this and pipeline multiple COPY requests. + */ + count = min_t(u64, count, 1 << 22); + return vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0); +} + __be32 nfsd4_vfs_fallocate(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, loff_t offset, loff_t len, int flags) |