Re: [PATCH v3 03/25] NFS41: Let layoutcommit handle multiple segments

From: Jim Rees <rees@umich.edu>
To: Boaz Harrosh <bharrosh@panasas.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>,
	linux-nfs@vger.kernel.org, peter honeyman <honey@citi.umich.edu>
Subject: Re: [PATCH v3 03/25] NFS41: Let layoutcommit handle multiple segments
Date: Wed, 27 Jul 2011 19:40:41 -0400	[thread overview]
Message-ID: <20110727234041.GC14319@merit.edu> (raw)
In-Reply-To: <4E307E6F.6090309@panasas.com>

Boaz Harrosh wrote:

  On 07/27/2011 01:58 PM, Jim Rees wrote:
  >   But I thought for simplicity since this patchset was reviewed then, I've
  >   tested with this patch and it works good as well. If you are going to
  >   break things up, I can test with the minimal patches and report what is
  >   need in Stable. (Is anyone working on it?)
  > 
  > We may have over-squashed that one for block layout.  I can dig up the
  > original patches if necessary, but I'm guessing you probably have them.
  
  Please do. Because by now I'm confused. the first I discovered it was
  by git diff of a branch that worked. I lost tracked of where the code
  was originated from.

Here is just the original multiple segments patch.  This is from the
88-patch set I sent out before Bakeathon.  I don't know if this would still
apply separately.

>From fc3381fa66adfcee4203b5a55ca6605bcfc8dafb Mon Sep 17 00:00:00 2001
From: Peng Tao <bergwolf@gmail.com>
Date: Tue, 31 May 2011 00:42:56 -0400
Subject: [PATCH 03/89] pnfs: let layoutcommit code handle multiple segments

Some layout driver like block will have multiple segments.
Generic code should be able to handle it.
---
 fs/nfs/pnfs.c |   15 ++++++++++++---
 fs/nfs/pnfs.h |    1 +
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index e3d618b..c18cda0 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1193,10 +1193,18 @@ pnfs_try_to_read_data(struct nfs_read_data *rdata,
 static struct pnfs_layout_segment *pnfs_list_write_lseg(struct inode *inode)
 {
 	struct pnfs_layout_segment *lseg, *rv = NULL;
+	loff_t max_pos = 0;
+
+	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
+		if (lseg->pls_range.iomode == IOMODE_RW) {
+			if (max_pos < lseg->pls_end_pos)
+				max_pos = lseg->pls_end_pos;
+			if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
+				rv = lseg;
+		}
+	}
+	rv->pls_end_pos = max_pos;
 
-	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list)
-		if (lseg->pls_range.iomode == IOMODE_RW)
-			rv = lseg;
 	return rv;
 }
 
@@ -1211,6 +1219,7 @@ pnfs_set_layoutcommit(struct nfs_write_data *wdata)
 	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
 		/* references matched in nfs4_layoutcommit_release */
 		get_lseg(wdata->lseg);
+		set_bit(NFS_LSEG_LAYOUTCOMMIT, &wdata->lseg->pls_flags);
 		wdata->lseg->pls_lc_cred =
 			get_rpccred(wdata->args.context->state->owner->so_cred);
 		mark_as_dirty = true;
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 53819d0..c6a9af2 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -36,6 +36,7 @@
 enum {
 	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
 	NFS_LSEG_ROC,		/* roc bit received from server */
+	NFS_LSEG_LAYOUTCOMMIT,	/* layoutcommit bit set for layoutcommit */
 };
 
 struct pnfs_layout_segment {
-- 
1.7.4.2
