NFS: Move the pnfs read code into pnfs.c
...and ensure that we recoalese to take into account differences in
block sizes when falling back to read through the MDS.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 5b3cc3f..9eca5a8 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -28,6 +28,7 @@
*/
#include <linux/nfs_fs.h>
+#include <linux/nfs_page.h>
#include "internal.h"
#include "pnfs.h"
#include "iostat.h"
@@ -1216,18 +1217,32 @@
}
EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
+static void
+pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
+ struct nfs_read_data *data)
+{
+ list_splice_tail_init(&data->pages, &desc->pg_list);
+ if (data->req && list_empty(&data->req->wb_list))
+ nfs_list_add_request(data->req, &desc->pg_list);
+ nfs_pageio_reset_read_mds(desc);
+ desc->pg_recoalesce = 1;
+ nfs_readdata_release(data);
+}
+
/*
* Call the appropriate parallel I/O subsystem read function.
*/
-enum pnfs_try_status
+static enum pnfs_try_status
pnfs_try_to_read_data(struct nfs_read_data *rdata,
- const struct rpc_call_ops *call_ops)
+ const struct rpc_call_ops *call_ops,
+ struct pnfs_layout_segment *lseg)
{
struct inode *inode = rdata->inode;
struct nfs_server *nfss = NFS_SERVER(inode);
enum pnfs_try_status trypnfs;
rdata->mds_ops = call_ops;
+ rdata->lseg = get_lseg(lseg);
dprintk("%s: Reading ino:%lu %u@%llu\n",
__func__, inode->i_ino, rdata->args.count, rdata->args.offset);
@@ -1243,6 +1258,44 @@
return trypnfs;
}
+static void
+pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *head)
+{
+ struct nfs_read_data *data;
+ const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
+ struct pnfs_layout_segment *lseg = desc->pg_lseg;
+
+ desc->pg_lseg = NULL;
+ while (!list_empty(head)) {
+ enum pnfs_try_status trypnfs;
+
+ data = list_entry(head->next, struct nfs_read_data, list);
+ list_del_init(&data->list);
+
+ trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);
+ if (trypnfs == PNFS_NOT_ATTEMPTED)
+ pnfs_read_through_mds(desc, data);
+ }
+ put_lseg(lseg);
+}
+
+int
+pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
+{
+ LIST_HEAD(head);
+ int ret;
+
+ ret = nfs_generic_pagein(desc, &head);
+ if (ret != 0) {
+ put_lseg(desc->pg_lseg);
+ desc->pg_lseg = NULL;
+ return ret;
+ }
+ pnfs_do_multiple_reads(desc, &head);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
+
/*
* Currently there is only one (whole file) write lseg.
*/
