From: Andreas Gruenbacher Subject: [PATCH v11 42/48] sunrpc: Allow to demand-allocate pages to encode into Date: Fri, 16 Oct 2015 17:18:20 +0200 Message-ID: <1445008706-15115-43-git-send-email-agruenba@redhat.com> References: <1445008706-15115-1-git-send-email-agruenba@redhat.com> To: Alexander Viro , "Theodore Ts'o" , Andreas Dilger , "J. Bruce Fields" , Jeff Layton , Trond Myklebust , Anna Schumaker , Dave Chinner , linux-ext4@vger.kernel.org, xfs@oss.sgi.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-api@vger.kernel.org Return-path: In-Reply-To: <1445008706-15115-1-git-send-email-agruenba@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org When encoding large, variable-length objects such as acls into xdr_bufs, it is easier to allocate buffer pages on demand rather than precomputing the required buffer size. Signed-off-by: Andreas Gruenbacher --- net/sunrpc/xdr.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index 4439ac4..63c1c36 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -537,6 +537,15 @@ static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr, */ xdr->scratch.iov_base = xdr->p; xdr->scratch.iov_len = frag1bytes; + + if (!*xdr->page_ptr) { + struct page *page = alloc_page(GFP_NOFS); + + if (!page) + return NULL; + *xdr->page_ptr = page; + } + p = page_address(*xdr->page_ptr); /* * Note this is where the next encode will start after we've -- 2.5.0