From: Sanath Kumar <sanath.s.kumar@oracle.com>
Date: Mon, 10 Apr 2017 21:52:32 +0000 (-0500)
Subject: sparc64: DAX request for non 4MB memory should return with unique errno
X-Git-Tag: v4.1.12-98.0.20170517_2143~33^2~6
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=f9ed59900b00a092f72a85d7ff54c2f0e789810c;p=users%2Fjedix%2Flinux-maple.git

sparc64: DAX request for non 4MB memory should return with unique errno

Orabug:25852910

With this change libdax can detect that mmap failed due to lack of flow
control in DAX HW and it can proceed with dax_subpage allocation.

Reviewed-by: Rob Gardner <rob.gardner@oracle.com>
Signed-off-by: Sanath Kumar <sanath.s.kumar@oracle.com>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
---

diff --git a/arch/sparc/dax/dax_mm.c b/arch/sparc/dax/dax_mm.c
index 510672d85539..031767e9bda9 100644
--- a/arch/sparc/dax/dax_mm.c
+++ b/arch/sparc/dax/dax_mm.c
@@ -44,6 +44,7 @@ static int dax_alloc_ram(struct file *filp, struct vm_area_struct *vma)
 	if (dax_no_flow_ctl && len != DAX_SYN_LARGE_PAGE_SIZE) {
 		dax_map_dbg("unsupported length 0x%lx != 0x%lx virtual page size",
 			    len, DAX_SYN_LARGE_PAGE_SIZE);
+		ret = -EOVERFLOW;
 		goto done;
 	}