nfsd: use vfs_iter_read/write
Instead of messing with the address limit to use vfs_read/vfs_writev.
Note that this requires that exported file implement ->read_iter and
->write_iter. All currently exportable file systems do this.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 2be3295..37a03c4 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -911,13 +911,12 @@
__be32 nfsd_readv(struct file *file, loff_t offset, struct kvec *vec, int vlen,
unsigned long *count)
{
- mm_segment_t oldfs;
+ struct iov_iter iter;
int host_err;
- oldfs = get_fs();
- set_fs(KERNEL_DS);
- host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset, 0);
- set_fs(oldfs);
+ iov_iter_kvec(&iter, READ | ITER_KVEC, vec, vlen, *count);
+ host_err = vfs_iter_read(file, &iter, &offset, 0);
+
return nfsd_finish_read(file, count, host_err);
}
@@ -974,7 +973,7 @@
unsigned long *cnt, int stable)
{
struct svc_export *exp;
- mm_segment_t oldfs;
+ struct iov_iter iter;
__be32 err = 0;
int host_err;
int use_wgather;
@@ -1000,10 +999,8 @@
if (stable && !use_wgather)
flags |= RWF_SYNC;
- /* Write the data. */
- oldfs = get_fs(); set_fs(KERNEL_DS);
- host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &pos, flags);
- set_fs(oldfs);
+ iov_iter_kvec(&iter, WRITE | ITER_KVEC, vec, vlen, *cnt);
+ host_err = vfs_iter_write(file, &iter, &pos, flags);
if (host_err < 0)
goto out_nfserr;
*cnt = host_err;