From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 14 Jan 2013 15:26:56 +0000 (+0100)
Subject: ide: fix TRIM with empty range entry
X-Git-Tag: qemu-xen-4.4.0-rc1~6^2~1400^2~8
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=80bc2e8d807939bee89d1a5ca0dbe89946d39ed1;p=qemu-upstream-4.4-testing.git

ide: fix TRIM with empty range entry

ATA-ACS-3 says "If the two byte range length is zero, then the LBA
Range Entry shall be discarded as padding."  iovecs are used as if
they are linearized, so it is incorrect to discard the rest of
this iovec.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---

diff --git a/hw/ide/core.c b/hw/ide/core.c
index 6f1938a0a..cb77dfcd4 100644
--- a/hw/ide/core.c
+++ b/hw/ide/core.c
@@ -374,7 +374,7 @@ BlockDriverAIOCB *ide_issue_trim(BlockDriverState *bs,
             uint16_t count = entry >> 48;
 
             if (count == 0) {
-                break;
+                continue;
             }
 
             ret = bdrv_discard(bs, sector, count);