[PATCH 5/8] pnfs-submit: request whole-file layouts only

[Alexandros Batsakis <batsakis@netapp.com>]

In the first iteration of the pNFS code, we support only whole file layouts.
To facilitate the move to multiple-segments, we keep the segment processing
code, but the segment list should always contain at most one segment per I/O type

Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
---
 fs/nfs/callback_proc.c |    7 ++++---
 fs/nfs/pnfs.c          |   25 ++++++++-----------------
 2 files changed, 12 insertions(+), 20 deletions(-)

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 8752239..16b4510 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -213,6 +213,10 @@ static int pnfs_recall_layout(void *data)
    then return layouts, resume after layoutreturns complete
  */
 
+	/* support whole file layouts only */
+	rl.cbl_seg.offset = 0;
+	rl.cbl_seg.length = NFS4_MAX_UINT64;
+
 	if (rl.cbl_recall_type == RETURN_FILE) {
 		status = pnfs_return_layout(inode, &rl.cbl_seg, &rl.cbl_stateid,
 					    RETURN_FILE, true);
@@ -221,9 +225,6 @@ static int pnfs_recall_layout(void *data)
 		goto out;
 	}
 
-	rl.cbl_seg.offset = 0;
-	rl.cbl_seg.length = NFS4_MAX_UINT64;
-
 	/* FIXME: This loop is inefficient, running in O(|s_inodes|^2) */
 	while ((ino = nfs_layoutrecall_find_inode(clp, &rl)) != NULL) {
 		/* XXX need to check status on pnfs_return_layout */
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index dd7ad26..8985e9f 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -551,12 +551,6 @@ pnfs_layout_from_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
 *    for now, assume that whole file layouts are requested.
 *    arg->offset: 0
 *    arg->length: all ones
-*
-*    for now, assume the LAYOUTGET operation is triggered by an I/O request.
-*    the count field is the count in the I/O request, and will be used
-*    as the minlength. for the file operation that piggy-backs
-*    the LAYOUTGET operation with an OPEN, s
-*    arg->minlength = count.
 */
 static int
 get_layout(struct inode *ino,
@@ -577,11 +571,11 @@ get_layout(struct inode *ino,
 		return -ENOMEM;
 	}
 	lgp->lo = lo;
-	lgp->args.minlength = PAGE_CACHE_SIZE;
+	lgp->args.minlength = NFS4_MAX_UINT64;
 	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 	lgp->args.lseg.iomode = range->iomode;
-	lgp->args.lseg.offset = range->offset;
-	lgp->args.lseg.length = max(range->length, lgp->args.minlength);
+	lgp->args.lseg.offset = 0;
+	lgp->args.lseg.length = NFS4_MAX_UINT64;
 	lgp->args.type = server->pnfs_curr_ld->id;
 	lgp->args.inode = ino;
 	lgp->lsegpp = lsegpp;
@@ -756,7 +750,7 @@ _pnfs_return_layout(struct inode *ino, struct nfs4_pnfs_layout_segment *range,
 	else {
 		arg.iomode = IOMODE_ANY;
 		arg.offset = 0;
-		arg.length = ~0;
+		arg.length = NFS4_MAX_UINT64;
 	}
 	if (type == RETURN_FILE) {
 		lo = get_lock_current_layout(nfsi);
@@ -1051,8 +1045,8 @@ pnfs_update_layout(struct inode *ino,
 {
 	struct nfs4_pnfs_layout_segment arg = {
 		.iomode = iomode,
-		.offset = pos,
-		.length = count
+		.offset = 0,
+		.length = ~0
 	};
 	struct nfs_inode *nfsi = NFS_I(ino);
 	struct pnfs_layout_type *lo;
@@ -1142,7 +1136,6 @@ out_put:
 void
 pnfs_get_layout_done(struct nfs4_pnfs_layoutget *lgp, int rpc_status)
 {
-	struct nfs4_pnfs_layoutget_res *res = &lgp->res;
 	struct pnfs_layout_segment *lseg = NULL;
 	struct nfs_inode *nfsi = PNFS_NFS_INODE(lgp->lo);
 	time_t suspend = 0;
@@ -1151,11 +1144,10 @@ pnfs_get_layout_done(struct nfs4_pnfs_layoutget *lgp, int rpc_status)
 
 	lgp->status = rpc_status;
 	if (likely(!rpc_status)) {
-		if (unlikely(res->layout.len <= 0)) {
+		if (unlikely(lgp->res.layout.len < 0)) {
 			printk(KERN_ERR
-			       "%s: ERROR!  Layout size is ZERO!\n", __func__);
+			       "%s: ERROR Returned layout size is ZERO\n", __func__);
 			lgp->status = -EIO;
-			goto get_out;
 		}
 		goto out;
 	}
@@ -1233,7 +1225,6 @@ pnfs_get_layout_done(struct nfs4_pnfs_layoutget *lgp, int rpc_status)
 		break;
 	}
 
-get_out:
 	/* remember that get layout failed and suspend trying */
 	nfsi->layout.pnfs_layout_suspend = suspend;
 	set_bit(lo_fail_bit(lgp->args.lseg.iomode),
-- 
1.6.2.5