NFSv4.1: Fix some issues with pnfs_generic_pg_test

1. If the intention is to coalesce requests 'prev' and 'req' then we
   have to ensure at least that we have a layout starting at
   req_offset(prev).

2. If we're only requesting a minimal layout of length desc->pg_count,
   we need to test the length actually returned by the server before
   we allow the coalescing to occur.

3. We need to deal correctly with (pgio->lseg == NULL)

4. Fixup the test guarding the pnfs_update_layout.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2011-06-10 13:30:22 -04:00
Родитель 19345cb299
Коммит 8f7d5efbef
2 изменённых файлов: 10 добавлений и 5 удалений

Просмотреть файл

@ -1000,6 +1000,9 @@ static bool objio_pg_test(struct nfs_pageio_descriptor *pgio,
if (!pnfs_generic_pg_test(pgio, prev, req))
return false;
if (pgio->pg_lseg == NULL)
return true;
return pgio->pg_count + req->wb_bytes <=
OBJIO_LSEG(pgio->pg_lseg)->max_io_size;
}

Просмотреть файл

@ -1064,19 +1064,21 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
gfp_flags = GFP_NOFS;
}
if (pgio->pg_count == prev->wb_bytes) {
if (pgio->pg_lseg == NULL) {
if (pgio->pg_count != prev->wb_bytes)
return true;
/* This is first coelesce call for a series of nfs_pages */
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
prev->wb_context,
req_offset(req),
req_offset(prev),
pgio->pg_count,
access_type,
gfp_flags);
return true;
if (pgio->pg_lseg == NULL)
return true;
}
if (pgio->pg_lseg &&
req_offset(req) > end_offset(pgio->pg_lseg->pls_range.offset,
if (req_offset(req) > end_offset(pgio->pg_lseg->pls_range.offset,
pgio->pg_lseg->pls_range.length))
return false;