From 73da852e3831bdc7a38d8d5fba178f35c923b264 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 27 May 2017 11:16:53 +0300 Subject: [PATCH] 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 Signed-off-by: Al Viro --- fs/nfsd/vfs.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 2be32955d7f2..37a03c456b38 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -911,13 +911,12 @@ __be32 nfsd_splice_read(struct svc_rqst *rqstp, __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 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, 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 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, 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;