blockdev: Fix regression in -drive if=scsi,index=N
Before commit 622b520f, index=12 meant bus=1,unit=5.
Since the commit, it means bus=0,unit=12. The drive is created, but
not the guest device. That's because the controllers we use with
if=scsi drives (lsi53c895a and esp) support only 7 units, and
scsi_bus_legacy_handle_cmdline() ignores drives with unit numbers
exceeding that limit.
Changing the mapping of index to bus, unit is a regression. Breaking
-drive invocations that used to work just makes it worse.
Revert the part of commit 622b520f that causes this, and clean up
some.
Note that the fix only affects if=scsi. You can still put more than 7
units on a SCSI bus with -device & friends.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/blockdev.c b/blockdev.c
index 9c883ce..fba53f9 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -32,8 +32,22 @@
};
static const int if_max_devs[IF_COUNT] = {
- [IF_IDE] = MAX_IDE_DEVS,
- [IF_SCSI] = MAX_SCSI_DEVS,
+ /*
+ * Do not change these numbers! They govern how drive option
+ * index maps to unit and bus. That mapping is ABI.
+ *
+ * All controllers used to imlement if=T drives need to support
+ * if_max_devs[T] units, for any T with if_max_devs[T] != 0.
+ * Otherwise, some index values map to "impossible" bus, unit
+ * values.
+ *
+ * For instance, if you change [IF_SCSI] to 255, -drive
+ * if=scsi,index=12 no longer means bus=1,unit=5, but
+ * bus=0,unit=12. With an lsi53c895a controller (7 units max),
+ * the drive can't be set up. Regression.
+ */
+ [IF_IDE] = 2,
+ [IF_SCSI] = 7,
};
/*
diff --git a/blockdev.h b/blockdev.h
index 2cbbb87..cf8fc01 100644
--- a/blockdev.h
+++ b/blockdev.h
@@ -37,9 +37,6 @@
QTAILQ_ENTRY(DriveInfo) next;
};
-#define MAX_IDE_DEVS 2
-#define MAX_SCSI_DEVS 255
-
DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit);
int drive_get_max_bus(BlockInterfaceType type);
DriveInfo *drive_get_next(BlockInterfaceType type);
diff --git a/hw/ide.h b/hw/ide.h
index 2b5ae7c..73fb550 100644
--- a/hw/ide.h
+++ b/hw/ide.h
@@ -4,6 +4,8 @@
#include "isa.h"
#include "pci.h"
+#define MAX_IDE_DEVS 2
+
/* ide-isa.c */
ISADevice *isa_ide_init(int iobase, int iobase2, int isairq,
DriveInfo *hd0, DriveInfo *hd1);
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index 433171c..671b4df 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -70,7 +70,6 @@
#include "monitor.h"
#include "dma.h"
#include "cpu-common.h"
-#include "blockdev.h"
#include "internal.h"
#include <hw/ide/pci.h>
diff --git a/hw/qdev.c b/hw/qdev.c
index 0c94fb2..c7fec44 100644
--- a/hw/qdev.c
+++ b/hw/qdev.c
@@ -29,7 +29,6 @@
#include "qdev.h"
#include "sysemu.h"
#include "monitor.h"
-#include "blockdev.h"
static int qdev_hotplug = 0;
static bool qdev_hot_added = false;
diff --git a/hw/scsi.h b/hw/scsi.h
index 846fbba..d3b5d56 100644
--- a/hw/scsi.h
+++ b/hw/scsi.h
@@ -3,9 +3,10 @@
#include "qdev.h"
#include "block.h"
-#include "blockdev.h"
#include "block_int.h"
+#define MAX_SCSI_DEVS 255
+
#define SCSI_CMD_BUF_SIZE 16
/* scsi-disk.c */
diff --git a/savevm.c b/savevm.c
index fcd8db4..4453217 100644
--- a/savevm.c
+++ b/savevm.c
@@ -78,7 +78,6 @@
#include "sysemu.h"
#include "qemu-timer.h"
#include "qemu-char.h"
-#include "blockdev.h"
#include "audio/audio.h"
#include "migration.h"
#include "qemu_socket.h"
