From de5542b5a8dc74f413bf2f1b0d5f4b370aa6801b Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Wed, 5 Jun 2019 13:57:05 +0200
Subject: [PATCH 17/23] qemu-io: Add write -n for BDRV_REQ_NO_FALLBACK

RH-Author: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: <20190605135705.24526-10-mlevitsk@redhat.com>
Patchwork-id: 88565
O-Subject: [RHEL-7.7 qemu-kvm-rhev PATCH 9/9] qemu-io: Add write -n for BDRV_REQ_NO_FALLBACK
Bugzilla: 1648622
RH-Acked-by: Max Reitz <mreitz@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: John Snow <jsnow@redhat.com>

From: Kevin Wolf <kwolf@redhat.com>

This makes the new BDRV_REQ_NO_FALLBACK flag available in the qemu-io
write command.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Eric Blake <eblake@redhat.com>

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1648622

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
(Cherry picked from c6e3f520c802c5cb2de80576aba7f9f1fe985d8b)

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 qemu-io-cmds.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index 9c51e57..ac8c533 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -945,6 +945,7 @@ static void write_help(void)
 " -b, -- write to the VM state rather than the virtual disk\n"
 " -c, -- write compressed data with blk_write_compressed\n"
 " -f, -- use Force Unit Access semantics\n"
+" -n, -- with -z, don't allow slow fallback\n"
 " -p, -- ignored for backwards compatibility\n"
 " -P, -- use different pattern to fill file\n"
 " -C, -- report statistics in a machine parsable format\n"
@@ -963,7 +964,7 @@ static const cmdinfo_t write_cmd = {
     .perm       = BLK_PERM_WRITE,
     .argmin     = 2,
     .argmax     = -1,
-    .args       = "[-bcCfquz] [-P pattern] off len",
+    .args       = "[-bcCfnquz] [-P pattern] off len",
     .oneline    = "writes a number of bytes at a specified offset",
     .help       = write_help,
 };
@@ -982,7 +983,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
     int64_t total = 0;
     int pattern = 0xcd;
 
-    while ((c = getopt(argc, argv, "bcCfpP:quz")) != -1) {
+    while ((c = getopt(argc, argv, "bcCfnpP:quz")) != -1) {
         switch (c) {
         case 'b':
             bflag = true;
@@ -996,6 +997,9 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
         case 'f':
             flags |= BDRV_REQ_FUA;
             break;
+        case 'n':
+            flags |= BDRV_REQ_NO_FALLBACK;
+            break;
         case 'p':
             /* Ignored for backwards compatibility */
             break;
@@ -1036,6 +1040,11 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
         return -EINVAL;
     }
 
+    if ((flags & BDRV_REQ_NO_FALLBACK) && !zflag) {
+        printf("-n requires -z to be specified\n");
+        return -EINVAL;
+    }
+
     if ((flags & BDRV_REQ_MAY_UNMAP) && !zflag) {
         printf("-u requires -z to be specified\n");
         return -EINVAL;
-- 
1.8.3.1