On Thu, Apr 01, 2021 at 09:27:56AM -0400, Olga Kornievskaia wrote: > On Wed, Mar 31, 2021 at 9:50 PM J. Bruce Fields <bfields@xxxxxxxxxx> wrote: > > > > On Wed, Mar 31, 2021 at 03:28:19PM -0400, Olga Kornievskaia wrote: > > > From: Olga Kornievskaia <kolga@xxxxxxxxxx> > > > > > > According to the RFC 7862, "if the server cannot find a > > > corresponding sa_what, then the status will still be NFS4_OK, > > > but sr_eof would be TRUE". If there is a file that ends with > > > a hole and a SEEK request made for sa_what=SEEK_DATA with > > > an offset in the middle of the last hole, then the server > > > has to return OK and set the eof. Currently the linux server > > > returns ERR_NXIO. > > > > Makes sense, but I think you can use the return value from vfs_llseek > > instead of checking the file size again. E.g.: > > > > seek->seek_pos = vfs_llseek(nfs->nf_file, seek->seek_offset, whence); > > if (seek->seek_pos == -ENXIO) > > seek->seek_eof = true; > > I don't believe this is correct. (1) ENXIO doesn't imply eof. If the > specified seek_offset was beyond the end of the file the server must > return ERR_NXIO and not OK. OK, never mind. > and (2) for the same reason I need to > check if the requested type was looking for data but didn't find it > because the offset is in the middle of the hole but still within the > file size (thus the need to check if the seek_offset is within the > file size). But I'm happy to check specifically if the seek_pos was > ENXIO (and not the generic negative error) and then also check if > request was for data and request was within file size. > > Also while I'm fixing this and have your attention, Can you tell if > the "else if" condition in the original code makes sense to you. I > didn't touch it but I don't think it's correct. "else if > (seek->seek_pos >= i_size_read(file_inode(nf->nf_file)))" I don't > believe this can ever happen. How can vfs_llseek() ever return a > position that is greater than the size of the file (or actually even > equal to it)? I agree, I don't get it either. --b. > > > else if (seek->seek_pos < 0) > > status = nfserrno(seek->seek_pos); > > > > --b. > > > > > > > > Fixes: 24bab491220fa ("NFSD: Implement SEEK") > > > Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx> > > > --- > > > fs/nfsd/nfs4proc.c | 10 +++++++--- > > > 1 file changed, 7 insertions(+), 3 deletions(-) > > > > > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > > > index e13c4c81fb89..2e7ceb9f1d5d 100644 > > > --- a/fs/nfsd/nfs4proc.c > > > +++ b/fs/nfsd/nfs4proc.c > > > @@ -1737,9 +1737,13 @@ nfsd4_seek(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > > > * should ever file->f_pos. > > > */ > > > seek->seek_pos = vfs_llseek(nf->nf_file, seek->seek_offset, whence); > > > - if (seek->seek_pos < 0) > > > - status = nfserrno(seek->seek_pos); > > > - else if (seek->seek_pos >= i_size_read(file_inode(nf->nf_file))) > > > + if (seek->seek_pos < 0) { > > > + if (whence == SEEK_DATA && > > > + seek->seek_offset < i_size_read(file_inode(nf->nf_file))) > > > + seek->seek_eof = true; > > > + else > > > + status = nfserrno(seek->seek_pos); > > > + } else if (seek->seek_pos >= i_size_read(file_inode(nf->nf_file))) > > > seek->seek_eof = true; > > > > > > out: > > > -- > > > 2.18.2 > > > > > >