block: Catch simultaneous usage of options and their aliases

While thinking about precedence of conflicting block device options from
different sources, I noticed that you can specify both an option and its
legacy alias at the same time (e.g. readonly=on,read-only=off). Rather
than specifying the order of precedence, we should simply forbid such
combinations.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>

3 files changed, 82 insertions, 2 deletions

diff --git a/blockdev.c b/blockdev.c
index 88f79282e9..ad436488b7 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -538,12 +538,18 @@ err_no_opts:
     return NULL;
 }
 
-static void qemu_opt_rename(QemuOpts *opts, const char *from, const char *to)
+static void qemu_opt_rename(QemuOpts *opts, const char *from, const char *to,
+                            Error **errp)
 {
     const char *value;
 
     value = qemu_opt_get(opts, from);
     if (value) {
+        if (qemu_opt_find(opts, to)) {
+            error_setg(errp, "'%s' and its alias '%s' can't be used at the "
+                       "same time", to, from);
+            return;
+        }
         qemu_opt_set(opts, to, value);
         qemu_opt_unset(opts, from);
     }
@@ -676,7 +682,13 @@ DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type)
     };
 
     for (i = 0; i < ARRAY_SIZE(opt_renames); i++) {
-        qemu_opt_rename(all_opts, opt_renames[i].from, opt_renames[i].to);
+        qemu_opt_rename(all_opts, opt_renames[i].from, opt_renames[i].to,
+                        &local_err);
+        if (local_err) {
+            error_report("%s", error_get_pretty(local_err));
+            error_free(local_err);
+            return NULL;
+        }
     }
 
     value = qemu_opt_get(all_opts, "cache");
diff --git a/tests/qemu-iotests/051 b/tests/qemu-iotests/051
index a41334e022..11c858f27d 100755
--- a/tests/qemu-iotests/051
+++ b/tests/qemu-iotests/051
@@ -199,6 +199,29 @@ run_qemu -drive file.driver=raw
 run_qemu -drive foo=bar
 
 echo
+echo === Specifying both an option and its legacy alias ===
+echo
+
+run_qemu -drive file="$TEST_IMG",iops=1234,throttling.iops-total=5678
+run_qemu -drive file="$TEST_IMG",iops_rd=1234,throttling.iops-read=5678
+run_qemu -drive file="$TEST_IMG",iops_wr=1234,throttling.iops-write=5678
+
+run_qemu -drive file="$TEST_IMG",bps=1234,throttling.bps-total=5678
+run_qemu -drive file="$TEST_IMG",bps_rd=1234,throttling.bps-read=5678
+run_qemu -drive file="$TEST_IMG",bps_wr=1234,throttling.bps-write=5678
+
+run_qemu -drive file="$TEST_IMG",iops_max=1234,throttling.iops-total-max=5678
+run_qemu -drive file="$TEST_IMG",iops_rd_max=1234,throttling.iops-read-max=5678
+run_qemu -drive file="$TEST_IMG",iops_wr_max=1234,throttling.iops-write-max=5678
+
+run_qemu -drive file="$TEST_IMG",bps_max=1234,throttling.bps-total-max=5678
+run_qemu -drive file="$TEST_IMG",bps_rd_max=1234,throttling.bps-read-max=5678
+run_qemu -drive file="$TEST_IMG",bps_wr_max=1234,throttling.bps-write-max=5678
+
+run_qemu -drive file="$TEST_IMG",iops_size=1234,throttling.iops-size=5678
+run_qemu -drive file="$TEST_IMG",readonly=on,read-only=off
+
+echo
 echo === Parsing protocol from file name ===
 echo
 
diff --git a/tests/qemu-iotests/051.out b/tests/qemu-iotests/051.out
index a3f28209c8..2c7e808765 100644
--- a/tests/qemu-iotests/051.out
+++ b/tests/qemu-iotests/051.out
@@ -274,6 +274,51 @@ Testing: -drive foo=bar
 QEMU_PROG: -drive foo=bar: could not open disk image ide0-hd0: Must specify either driver or file
 
 
+=== Specifying both an option and its legacy alias ===
+
+Testing: -drive file=TEST_DIR/t.qcow2,iops=1234,throttling.iops-total=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,iops=1234,throttling.iops-total=5678: 'throttling.iops-total' and its alias 'iops' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,iops_rd=1234,throttling.iops-read=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,iops_rd=1234,throttling.iops-read=5678: 'throttling.iops-read' and its alias 'iops_rd' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,iops_wr=1234,throttling.iops-write=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,iops_wr=1234,throttling.iops-write=5678: 'throttling.iops-write' and its alias 'iops_wr' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,bps=1234,throttling.bps-total=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,bps=1234,throttling.bps-total=5678: 'throttling.bps-total' and its alias 'bps' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,bps_rd=1234,throttling.bps-read=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,bps_rd=1234,throttling.bps-read=5678: 'throttling.bps-read' and its alias 'bps_rd' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,bps_wr=1234,throttling.bps-write=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,bps_wr=1234,throttling.bps-write=5678: 'throttling.bps-write' and its alias 'bps_wr' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,iops_max=1234,throttling.iops-total-max=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,iops_max=1234,throttling.iops-total-max=5678: 'throttling.iops-total-max' and its alias 'iops_max' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,iops_rd_max=1234,throttling.iops-read-max=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,iops_rd_max=1234,throttling.iops-read-max=5678: 'throttling.iops-read-max' and its alias 'iops_rd_max' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,iops_wr_max=1234,throttling.iops-write-max=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,iops_wr_max=1234,throttling.iops-write-max=5678: 'throttling.iops-write-max' and its alias 'iops_wr_max' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,bps_max=1234,throttling.bps-total-max=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,bps_max=1234,throttling.bps-total-max=5678: 'throttling.bps-total-max' and its alias 'bps_max' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,bps_rd_max=1234,throttling.bps-read-max=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,bps_rd_max=1234,throttling.bps-read-max=5678: 'throttling.bps-read-max' and its alias 'bps_rd_max' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,bps_wr_max=1234,throttling.bps-write-max=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,bps_wr_max=1234,throttling.bps-write-max=5678: 'throttling.bps-write-max' and its alias 'bps_wr_max' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,iops_size=1234,throttling.iops-size=5678
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,iops_size=1234,throttling.iops-size=5678: 'throttling.iops-size' and its alias 'iops_size' can't be used at the same time
+
+Testing: -drive file=TEST_DIR/t.qcow2,readonly=on,read-only=off
+QEMU_PROG: -drive file=TEST_DIR/t.qcow2,readonly=on,read-only=off: 'read-only' and its alias 'readonly' can't be used at the same time
+
+
 === Parsing protocol from file name ===
 
 Testing: -hda foo:bar