NFSv4.1: define nfs_generic_pg_test
By default, unless pnfs is used coalesce pages until pg_bsize
(rsize or wsize) is reached.
pnfs layout drivers define their own pg_test methods that use
pnfs_generic_pg_test and need to define their own I/O size
limits (e.g. based on the file stripe size).
[Move a check from nfs_pageio_do_add_request to nfs_generic_pg_test]
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 5344371..7913961 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -204,6 +204,21 @@
TASK_UNINTERRUPTIBLE);
}
+static bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *prev, struct nfs_page *req)
+{
+ /*
+ * FIXME: ideally we should be able to coalesce all requests
+ * that are not block boundary aligned, but currently this
+ * is problematic for the case of bsize < PAGE_CACHE_SIZE,
+ * since nfs_flush_multi and nfs_pagein_multi assume you
+ * can have only one struct nfs_page.
+ */
+ if (desc->pg_bsize < PAGE_SIZE)
+ return 0;
+
+ return desc->pg_count + req->wb_bytes <= desc->pg_bsize;
+}
+
/**
* nfs_pageio_init - initialise a page io descriptor
* @desc: pointer to descriptor
@@ -229,7 +244,7 @@
desc->pg_ioflags = io_flags;
desc->pg_error = 0;
desc->pg_lseg = NULL;
- desc->pg_test = NULL;
+ desc->pg_test = nfs_generic_pg_test;
pnfs_pageio_init(desc, inode);
}
@@ -260,13 +275,7 @@
return false;
if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE)
return false;
- /*
- * Non-whole file layouts need to check that req is inside of
- * pgio->pg_lseg.
- */
- if (pgio->pg_test && !pgio->pg_test(pgio, prev, req))
- return false;
- return true;
+ return pgio->pg_test(pgio, prev, req);
}
/**
@@ -280,31 +289,18 @@
static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
struct nfs_page *req)
{
- size_t newlen = req->wb_bytes;
-
if (desc->pg_count != 0) {
struct nfs_page *prev;
- /*
- * FIXME: ideally we should be able to coalesce all requests
- * that are not block boundary aligned, but currently this
- * is problematic for the case of bsize < PAGE_CACHE_SIZE,
- * since nfs_flush_multi and nfs_pagein_multi assume you
- * can have only one struct nfs_page.
- */
- if (desc->pg_bsize < PAGE_SIZE)
- return 0;
- newlen += desc->pg_count;
- if (newlen > desc->pg_bsize)
- return 0;
prev = nfs_list_entry(desc->pg_list.prev);
if (!nfs_can_coalesce_requests(prev, req, desc))
return 0;
- } else
+ } else {
desc->pg_base = req->wb_pgbase;
+ }
nfs_list_remove_request(req);
nfs_list_add_request(req, &desc->pg_list);
- desc->pg_count = newlen;
+ desc->pg_count += req->wb_bytes;
return 1;
}