From: Juergen Gross jgr...@suse.com
Introduces the XEN pvSCSI backend. With pvSCSI it is possible for a XEN domU
to issue SCSI commands to a SCSI LUN assigned to that domU. The SCSI commands
are passed to the pvSCSI backend in a driver domain (usually Dom0) which is
owner of the physical device. This allows e.g. to use SCSI tape drives in a
XEN domU.
The code is taken from the pvSCSI implementation in XEN done by Fujitsu based
on Linux kernel 2.6.18.
Changes from the original version are:
- port to upstream kernel
- put all code in just one source file
- adapt to Linux style guide
- use target core infrastructure instead doing pure pass-through
- enable module unloading
- support SG-list in grant page(s)
- support task abort
- remove redundant struct backend
- allocate resources dynamically
- correct minor error in scsiback_fast_flush_area
- free allocated resources in case of error during I/O preparation
- initialize SCSI emulation table statically
- fix emulation of report LUNs to not needing retry
Signed-off-by: Juergen Gross jgr...@suse.com
---
drivers/xen/Kconfig|9 +
drivers/xen/Makefile |1 +
drivers/xen/xen-scsiback.c | 2655
3 files changed, 2665 insertions(+)
create mode 100644 drivers/xen/xen-scsiback.c
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index 38fb36e..fc8f420 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -172,6 +172,15 @@ config XEN_PCIDEV_BACKEND
If in doubt, say m.
+config XEN_SCSI_BACKEND
+ tristate XEN SCSI backend driver
+ depends on SCSI XEN XEN_BACKEND TARGET_CORE
+ help
+ The SCSI backend driver allows the kernel to export its SCSI Devices
+ to other guests via a high-performance shared-memory interface.
+ Only needed for systems running as XEN driver domains (e.g. Dom0) and
+ if guests need generic access to SCSI devices.
+
config XEN_PRIVCMD
tristate
depends on XEN
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index 45e00af..b42ee75 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_XEN_STUB)+= xen-stub.o
obj-$(CONFIG_XEN_ACPI_HOTPLUG_MEMORY) += xen-acpi-memhotplug.o
obj-$(CONFIG_XEN_ACPI_HOTPLUG_CPU) += xen-acpi-cpuhotplug.o
obj-$(CONFIG_XEN_ACPI_PROCESSOR) += xen-acpi-processor.o
+obj-$(CONFIG_XEN_SCSI_BACKEND) += xen-scsiback.o
xen-evtchn-y := evtchn.o
xen-gntdev-y := gntdev.o
xen-gntalloc-y := gntalloc.o
diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c
new file mode 100644
index 000..6eed255
--- /dev/null
+++ b/drivers/xen/xen-scsiback.c
@@ -0,0 +1,2655 @@
+/*
+ * Xen SCSI backend driver
+ *
+ * Copyright (c) 2008, FUJITSU Limited
+ *
+ * Based on the blkback driver code.
+ * Adaption to kernel taget core infrastructure taken from vhost/scsi.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the Software), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+/*
+ * Patched to support 2TB drives + allow tape autoloader operations
+ * 2010, Samuel Kvasnica, IMS Nanofabrication AG
+ */
+
+#include stdarg.h
+
+#include linux/module.h
+#include linux/utsname.h
+#include linux/interrupt.h
+#include linux/slab.h
+#include linux/wait.h
+#include linux/sched.h
+#include linux/blkdev.h
+#include linux/list.h
+#include linux/gfp.h
+#include linux/kthread.h
+#include linux/delay.h
+#include linux/vmalloc.h
+#include linux/spinlock.h
+#include linux/configfs.h
+
+#include generated/utsrelease.h
+
+#include scsi/scsi.h
+#include scsi/scsi_cmnd.h
