From 5f919c9f10c1cf821ee5f414683214a361a1b98c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 21 Aug 2014 11:09:25 -0500 Subject: pnfs: allow splicing pre-encoded pages into the layoutcommit args Currently there is no XDR buffer space allocated for the per-layout driver layoutcommit payload, which leads to server buffer overflows in the blocklayout driver even under simple workloads. As we can't do per-layout sizes for XDR operations we'll have to splice a previously encoded list of pages into the XDR stream, similar to how we handle ACL buffers. Signed-off-by: Christoph Hellwig Signed-off-by: Trond Myklebust --- fs/nfs/nfs4xdr.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) (limited to 'fs/nfs/nfs4xdr.c') diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index e13b59d8d9aa..f2cd957adb90 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -395,7 +395,10 @@ static int nfs4_stat_to_errno(int); 2 /* last byte written */ + \ 1 /* nt_timechanged (false) */ + \ 1 /* layoutupdate4 layout type */ + \ - 1 /* NULL filelayout layoutupdate4 payload */) + 1 /* layoutupdate4 opaqueue len */) + /* the actual content of layoutupdate4 should + be allocated by drivers and spliced in + using xdr_write_pages */ #define decode_layoutcommit_maxsz (op_decode_hdr_maxsz + 3) #define encode_layoutreturn_maxsz (8 + op_encode_hdr_maxsz + \ encode_stateid_maxsz + \ @@ -1990,7 +1993,7 @@ encode_layoutget(struct xdr_stream *xdr, static int encode_layoutcommit(struct xdr_stream *xdr, struct inode *inode, - const struct nfs4_layoutcommit_args *args, + struct nfs4_layoutcommit_args *args, struct compound_hdr *hdr) { __be32 *p; @@ -2011,11 +2014,16 @@ encode_layoutcommit(struct xdr_stream *xdr, *p++ = cpu_to_be32(0); /* Never send time_modify_changed */ *p++ = cpu_to_be32(NFS_SERVER(args->inode)->pnfs_curr_ld->id);/* type */ - if (NFS_SERVER(inode)->pnfs_curr_ld->encode_layoutcommit) + if (NFS_SERVER(inode)->pnfs_curr_ld->encode_layoutcommit) { NFS_SERVER(inode)->pnfs_curr_ld->encode_layoutcommit( NFS_I(inode)->layout, xdr, args); - else - encode_uint32(xdr, 0); /* no layout-type payload */ + } else { + encode_uint32(xdr, args->layoutupdate_len); + if (args->layoutupdate_pages) { + xdr_write_pages(xdr, args->layoutupdate_pages, 0, + args->layoutupdate_len); + } + } return 0; } -- cgit v1.2.3-70-g09d2