On Thu, Dec 3, 2020 at 3:27 PM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote: > > > > > On Dec 3, 2020, at 3:18 PM, schumaker.anna@xxxxxxxxx wrote: > > > > From: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> > > > > We might need this to better handle shifting around data in the reply > > buffer. > > > > Suggested-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> > > Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> > > --- > > fs/nfs/nfs42xdr.c | 2 ++ > > fs/nfs/read.c | 13 +++++++++++-- > > include/linux/nfs_xdr.h | 1 + > > 3 files changed, 14 insertions(+), 2 deletions(-) > > > > diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c > > index 8432bd6b95f0..ef095a5f86f7 100644 > > --- a/fs/nfs/nfs42xdr.c > > +++ b/fs/nfs/nfs42xdr.c > > @@ -1297,6 +1297,8 @@ static int nfs4_xdr_dec_read_plus(struct rpc_rqst *rqstp, > > struct compound_hdr hdr; > > int status; > > > > + xdr_set_scratch_buffer(xdr, page_address(res->scratch), PAGE_SIZE); > > I intend to submit this for v5.11: > > https://git.linux-nfs.org/?p=cel/cel-2.6.git;a=commit;h=0ae4c3e8a64ace1b8d7de033b0751afe43024416 Thanks for the heads up! This patch can probably be deferred until yours goes in. > > But seems like enough callers need a scratch buffer that the XDR > layer should set up it transparently for all requests. That could work too, and save some headache. Anna > > > > + > > status = decode_compound_hdr(xdr, &hdr); > > if (status) > > goto out; > > diff --git a/fs/nfs/read.c b/fs/nfs/read.c > > index eb854f1f86e2..012deb5a136f 100644 > > --- a/fs/nfs/read.c > > +++ b/fs/nfs/read.c > > @@ -37,15 +37,24 @@ static struct kmem_cache *nfs_rdata_cachep; > > > > static struct nfs_pgio_header *nfs_readhdr_alloc(void) > > { > > - struct nfs_pgio_header *p = kmem_cache_zalloc(nfs_rdata_cachep, GFP_KERNEL); > > + struct nfs_pgio_header *p; > > + struct page *page; > > > > - if (p) > > + page = alloc_page(GFP_KERNEL); > > + if (!page) > > + return ERR_PTR(-ENOMEM); > > + > > + p = kmem_cache_zalloc(nfs_rdata_cachep, GFP_KERNEL); > > + if (p) { > > p->rw_mode = FMODE_READ; > > + p->res.scratch = page; > > + } > > return p; > > } > > > > static void nfs_readhdr_free(struct nfs_pgio_header *rhdr) > > { > > + __free_page(rhdr->res.scratch); > > kmem_cache_free(nfs_rdata_cachep, rhdr); > > } > > > > diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h > > index d63cb862d58e..e0a1c97f11a9 100644 > > --- a/include/linux/nfs_xdr.h > > +++ b/include/linux/nfs_xdr.h > > @@ -659,6 +659,7 @@ struct nfs_pgio_res { > > struct nfs_fattr * fattr; > > __u64 count; > > __u32 op_status; > > + struct page * scratch; > > union { > > struct { > > unsigned int replen; /* used by read */ > > -- > > 2.29.2 > > > > -- > Chuck Lever > > >
