nfs: chain calls to pg_test

Now that pg_test can change the size of the request (by returning a non-zero
size smaller than the request), pg_test functions that call other
pg_test functions must return the minimum of the result - or 0 if any fail.

Also clean up the logic of some pg_test functions so that all checks are
for contitions where coalescing is not possible.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Weston Andros Adamson 2014-05-15 11:56:51 -04:00 committed by Trond Myklebust
parent 6094f83864
commit 0f9c429eca
3 changed files with 30 additions and 21 deletions

View File

@ -928,26 +928,27 @@ static size_t
filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
struct nfs_page *req)
{
unsigned int size;
u64 p_stripe, r_stripe;
u32 stripe_unit;
if (!pnfs_generic_pg_test(pgio, prev, req) ||
!nfs_generic_pg_test(pgio, prev, req))
/* calls nfs_generic_pg_test */
size = pnfs_generic_pg_test(pgio, prev, req);
if (!size)
return 0;
if (!prev)
return req->wb_bytes;
if (prev) {
p_stripe = (u64)req_offset(prev);
r_stripe = (u64)req_offset(req);
stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
p_stripe = (u64)req_offset(prev);
r_stripe = (u64)req_offset(req);
stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
do_div(p_stripe, stripe_unit);
do_div(r_stripe, stripe_unit);
do_div(p_stripe, stripe_unit);
do_div(r_stripe, stripe_unit);
if (p_stripe == r_stripe)
return req->wb_bytes;
return 0;
if (p_stripe != r_stripe)
return 0;
}
return min(size, req->wb_bytes);
}
static void

View File

@ -571,12 +571,15 @@ int objio_write_pagelist(struct nfs_pgio_data *wdata, int how)
static size_t objio_pg_test(struct nfs_pageio_descriptor *pgio,
struct nfs_page *prev, struct nfs_page *req)
{
if (!pnfs_generic_pg_test(pgio, prev, req) ||
pgio->pg_count + req->wb_bytes >
unsigned int size;
size = pnfs_generic_pg_test(pgio, prev, req);
if (!size || pgio->pg_count + req->wb_bytes >
(unsigned long)pgio->pg_layout_private)
return 0;
return req->wb_bytes;
return min(size, req->wb_bytes);
}
static void objio_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)

View File

@ -1442,8 +1442,12 @@ size_t
pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
struct nfs_page *req)
{
if (pgio->pg_lseg == NULL)
return nfs_generic_pg_test(pgio, prev, req);
unsigned int size;
size = nfs_generic_pg_test(pgio, prev, req);
if (!size)
return 0;
/*
* Test if a nfs_page is fully contained in the pnfs_layout_range.
@ -1459,10 +1463,11 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
* first byte that lies outside the pnfs_layout_range. FIXME?
*
*/
if (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 req->wb_bytes;
return 0;
return 0;
return min(size, req->wb_bytes);
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);