NFS: Prevent 3.0 from crashing if it receives a partial layout

This is a backport of critical parts of
commit 7c24d9489f "NFSv4.1: File layout only supports whole file layouts"

It prevents the file layout driver from (incorrectly) using
partial layouts, but ignores the part of the referenced commmit that
relies on additional machinery to change the LAYOUTGET request
based on layout driver.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 614c4d287d72c6521b08356fcfee4379f753249b..75af81211e4f953db666ea96f183a0f73f5100e4 100644 (file)
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -428,6 +428,14 @@ filelayout_check_layout(struct pnfs_layout_hdr *lo,
 
        dprintk("--> %s\n", __func__);
 
+       /* FIXME: remove this check when layout segment support is added */
+       if (lgr->range.offset != 0 ||
+           lgr->range.length != NFS4_MAX_UINT64) {
+               dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
+                       __func__);
+               goto out;
+       }
+
        if (fl->pattern_offset > lgr->range.offset) {
                dprintk("%s pattern_offset %lld too large\n",
                                __func__, fl->pattern_offset);

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index a726c0afa76ea364348d8514623b023ca454a711..36d2a29bfbedcb0e24fbded77770e5a062efdf80 100644 (file)
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -980,7 +980,8 @@ pnfs_update_layout(struct inode *ino,
                arg.offset -= pg_offset;
                arg.length += pg_offset;
        }
-       arg.length = PAGE_CACHE_ALIGN(arg.length);
+       if (arg.length != NFS4_MAX_UINT64)
+               arg.length = PAGE_CACHE_ALIGN(arg.length);
 
        lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
        if (!lseg && first) {