From 2d89a1d3c9ff8ceb115f001e66cff9788338ca47 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Mon, 31 Aug 2015 02:05:47 -0700
Subject: [PATCH] NFSv4.1/pNFS: Don't request a minimal read layout beyond the
end of file
If we have a read layout, then sanity check the minimal layout length
so that it does not extend beyond the end of file.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
---
fs/nfs/pnfs.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index c4f918eca3d2..ba1246433794 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -868,6 +868,7 @@ send_layoutget(struct pnfs_layout_hdr *lo,
struct nfs_server *server = NFS_SERVER(ino);
struct nfs4_layoutget *lgp;
struct pnfs_layout_segment *lseg;
+ loff_t i_size;
dprintk("--> %s\n", __func__);
@@ -875,9 +876,17 @@ send_layoutget(struct pnfs_layout_hdr *lo,
if (lgp == NULL)
return NULL;
+ i_size = i_size_read(ino);
+
lgp->args.minlength = PAGE_CACHE_SIZE;
if (lgp->args.minlength > range->length)
lgp->args.minlength = range->length;
+ if (range->iomode == IOMODE_READ) {
+ if (range->offset >= i_size)
+ lgp->args.minlength = 0;
+ else if (i_size - range->offset < lgp->args.minlength)
+ lgp->args.minlength = i_size - range->offset;
+ }
lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
lgp->args.range = *range;
lgp->args.type = server->pnfs_curr_ld->id;