From: The pNFS Team <linux-nfs@xxxxxxxxxxxxxxx>
Signed-off-by: Andy Adamson <andros@xxxxxxxxxx>
---
fs/nfs/nfs4filelayout.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 88 insertions(+), 0 deletions(-)
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index d1c0d35..c9251ca 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -124,6 +124,93 @@ filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
}
/*
+ * Call ops for the async read/write cases
+ * In the case of dense layouts, the offset needs to be reset to its
+ * original value.
+ */
+static void filelayout_read_call_done(struct rpc_task *task, void *data)
+{
+ struct nfs_read_data *rdata = (struct nfs_read_data *)data;
+
+ if (rdata->fldata.orig_offset) {
+ dprintk("%s new off %llu orig offset %llu\n", __func__,
+ rdata->args.offset, rdata->fldata.orig_offset);
+ rdata->args.offset = rdata->fldata.orig_offset;
+ }
+
+ /* Note this may cause RPC to be resent */
+ rdata->pdata.call_ops->rpc_call_done(task, data);
+}
+
+static void filelayout_read_release(void *data)
+{
+ struct nfs_read_data *rdata = (struct nfs_read_data *)data;
+
+ put_lseg(rdata->pdata.lseg);
+ rdata->pdata.lseg = NULL;
+ rdata->pdata.call_ops->rpc_release(data);
+}
+
+struct rpc_call_ops filelayout_read_call_ops = {
+ .rpc_call_prepare = nfs_read_prepare,
+ .rpc_call_done = filelayout_read_call_done,
+ .rpc_release = filelayout_read_release,
+};
+
+/* Perform sync or async reads.
+ *
+ * An optimization for the NFS file layout driver
+ * allows the original read/write data structs to be passed in the
+ * last argument.
+ *
+ * TODO: join with write_pagelist?
+ */
+static enum pnfs_try_status
+filelayout_read_pagelist(struct nfs_read_data *data, unsigned nr_pages)
+{
+ struct pnfs_layout_segment *lseg = data->pdata.lseg;
+ struct nfs4_pnfs_ds *ds;
+ loff_t offset = data->args.offset;
+ u32 idx;
+ struct nfs_fh *fh;
+
+ dprintk("--> %s ino %lu nr_pages %d pgbase %u req %Zu@%llu\n",
+ __func__, data->inode->i_ino, nr_pages,
+ data->args.pgbase, (size_t)data->args.count, offset);
+
+ /* Retrieve the correct rpc_client for the byte range */
+ idx = nfs4_fl_calc_ds_index(lseg, offset);
+ ds = nfs4_fl_prepare_ds(lseg, idx);
+ if (!ds) {
+ printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
+ return PNFS_NOT_ATTEMPTED;
+ }
+ dprintk("%s USE DS:ip %x %s\n", __func__,
+ htonl(ds->ds_ip_addr), ds->r_addr);
+
+ /* just try the first data server for the index..*/
+ data->fldata.ds_nfs_client = ds->ds_clp;
+ fh = nfs4_fl_select_ds_fh(lseg, offset);
+ if (fh)
+ data->args.fh = fh;
+
+ /*
+ * Now get the file offset on the dserver
+ * Set the read offset to this offset, and
+ * save the original offset in orig_offset
+ * In the case of aync reads, the offset will be reset in the
+ * call_ops->rpc_call_done() routine.
+ */
+ data->args.offset = filelayout_get_dserver_offset(lseg, offset);
+ data->fldata.orig_offset = offset;
+
+ /* Perform an asynchronous read */
+ nfs_initiate_read(data, ds->ds_clp->cl_rpcclient,
+ &filelayout_read_call_ops);
+ return PNFS_ATTEMPTED;
+}
+
+/*
* Create a filelayout layout structure and return it. The pNFS client
* will use the pnfs_layout_type type to refer to the layout for this
* inode from now on.
@@ -377,6 +464,7 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
}
struct layoutdriver_io_operations filelayout_io_operations = {
+ .read_pagelist = filelayout_read_pagelist,
.alloc_layout = filelayout_alloc_layout,
.free_layout = filelayout_free_layout,
.alloc_lseg = filelayout_alloc_lseg,
--
1.6.2.5
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