WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-changelog

[Xen-changelog] [linux-2.6.18-xen] pvSCSI frontend driver

To: xen-changelog@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-changelog] [linux-2.6.18-xen] pvSCSI frontend driver
From: "Xen patchbot-linux-2.6.18-xen" <patchbot-linux-2.6.18-xen@xxxxxxxxxxxxxxxxxxx>
Date: Mon, 02 Jun 2008 08:40:09 -0700
Delivery-date: Mon, 02 Jun 2008 08:40:27 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-changelog-request@lists.xensource.com?subject=help>
List-id: BK change log <xen-changelog.lists.xensource.com>
List-post: <mailto:xen-changelog@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=unsubscribe>
Reply-to: xen-devel@xxxxxxxxxxxxxxxxxxx
Sender: xen-changelog-bounces@xxxxxxxxxxxxxxxxxxx
# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1212397136 -3600
# Node ID 3b3701ad4eece5b99e88394d15846c2fc54a4506
# Parent  66faefe721ebb4c9490f3b06b653386d9d2ad4af
pvSCSI frontend driver

Signed-off-by: Tomonari Horikoshi <t.horikoshi@xxxxxxxxxxxxxx>
Signed-off-by: Jun Kamada <kama@xxxxxxxxxxxxxx>
---
 buildconfigs/linux-defconfig_xen0_ia64   |    1 
 buildconfigs/linux-defconfig_xen0_x86_32 |    1 
 buildconfigs/linux-defconfig_xen0_x86_64 |    1 
 buildconfigs/linux-defconfig_xenU_ia64   |    1 
 buildconfigs/linux-defconfig_xenU_x86_32 |    1 
 buildconfigs/linux-defconfig_xenU_x86_64 |    1 
 buildconfigs/linux-defconfig_xen_ia64    |    1 
 buildconfigs/linux-defconfig_xen_x86_32  |    1 
 buildconfigs/linux-defconfig_xen_x86_64  |    1 
 drivers/xen/Kconfig                      |    8 
 drivers/xen/Makefile                     |    1 
 drivers/xen/scsifront/Makefile           |    3 
 drivers/xen/scsifront/common.h           |  132 +++++++
 drivers/xen/scsifront/scsifront.c        |  519 +++++++++++++++++++++++++++++++
 drivers/xen/scsifront/xenbus.c           |  446 ++++++++++++++++++++++++++
 15 files changed, 1118 insertions(+)

diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xen0_ia64
--- a/buildconfigs/linux-defconfig_xen0_ia64    Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xen0_ia64    Mon Jun 02 09:58:56 2008 +0100
@@ -1684,6 +1684,7 @@ CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 CONFIG_XEN_GRANT_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_FRAMEBUFFER=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xen0_x86_32
--- a/buildconfigs/linux-defconfig_xen0_x86_32  Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xen0_x86_32  Mon Jun 02 09:58:56 2008 +0100
@@ -1421,6 +1421,7 @@ CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 CONFIG_XEN_GRANT_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_SCRUB_PAGES=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xen0_x86_64
--- a/buildconfigs/linux-defconfig_xen0_x86_64  Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xen0_x86_64  Mon Jun 02 09:58:56 2008 +0100
@@ -1362,6 +1362,7 @@ CONFIG_XEN_PCIDEV_BACKEND_PASS=y
 # CONFIG_XEN_SCSI_BACKEND is not set
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 CONFIG_XEN_GRANT_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_SCRUB_PAGES=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xenU_ia64
--- a/buildconfigs/linux-defconfig_xenU_ia64    Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xenU_ia64    Mon Jun 02 09:58:56 2008 +0100
@@ -1492,6 +1492,7 @@ CONFIG_XEN_XENBUS_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_UTIL is not set
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 # CONFIG_XEN_GRANT_DEV is not set
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_FRAMEBUFFER=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xenU_x86_32
--- a/buildconfigs/linux-defconfig_xenU_x86_32  Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xenU_x86_32  Mon Jun 02 09:58:56 2008 +0100
@@ -916,6 +916,7 @@ CONFIG_XEN_XENBUS_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_UTIL is not set
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 # CONFIG_XEN_GRANT_DEV is not set
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_SCRUB_PAGES=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xenU_x86_64
--- a/buildconfigs/linux-defconfig_xenU_x86_64  Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xenU_x86_64  Mon Jun 02 09:58:56 2008 +0100
@@ -878,6 +878,7 @@ CONFIG_XEN_XENBUS_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_UTIL is not set
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 CONFIG_XEN_GRANT_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_SCRUB_PAGES=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xen_ia64
--- a/buildconfigs/linux-defconfig_xen_ia64     Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xen_ia64     Mon Jun 02 09:58:56 2008 +0100
@@ -1684,6 +1684,7 @@ CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 CONFIG_XEN_GRANT_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_FRAMEBUFFER=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xen_x86_32
--- a/buildconfigs/linux-defconfig_xen_x86_32   Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xen_x86_32   Mon Jun 02 09:58:56 2008 +0100
@@ -3279,6 +3279,7 @@ CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 CONFIG_XEN_GRANT_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_FRAMEBUFFER=y
diff -r 66faefe721eb -r 3b3701ad4eec buildconfigs/linux-defconfig_xen_x86_64
--- a/buildconfigs/linux-defconfig_xen_x86_64   Mon Jun 02 09:58:27 2008 +0100
+++ b/buildconfigs/linux-defconfig_xen_x86_64   Mon Jun 02 09:58:56 2008 +0100
@@ -3109,6 +3109,7 @@ CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_SCSI_BACKEND=m
 CONFIG_XEN_BLKDEV_FRONTEND=y
 CONFIG_XEN_NETDEV_FRONTEND=y
+CONFIG_XEN_SCSI_FRONTEND=m
 CONFIG_XEN_GRANT_DEV=y
 # CONFIG_XEN_NETDEV_ACCEL_SFC_FRONTEND is not set
 CONFIG_XEN_FRAMEBUFFER=y
diff -r 66faefe721eb -r 3b3701ad4eec drivers/xen/Kconfig
--- a/drivers/xen/Kconfig       Mon Jun 02 09:58:27 2008 +0100
+++ b/drivers/xen/Kconfig       Mon Jun 02 09:58:56 2008 +0100
@@ -199,6 +199,14 @@ config XEN_NETDEV_ACCEL_SFC_FRONTEND
        select XEN_NETDEV_ACCEL_SFC_UTIL
        default m
 
+config XEN_SCSI_FRONTEND
+       tristate "SCSI frontend driver"
+       depends on SCSI
+       default m
+       help
+         The SCSI frontend driver allows the kernel to access SCSI Devices
+         within another guest OS.
+
 config XEN_GRANT_DEV
        tristate "User-space granted page access driver"
        default XEN_PRIVILEGED_GUEST
diff -r 66faefe721eb -r 3b3701ad4eec drivers/xen/Makefile
--- a/drivers/xen/Makefile      Mon Jun 02 09:58:27 2008 +0100
+++ b/drivers/xen/Makefile      Mon Jun 02 09:58:56 2008 +0100
@@ -17,6 +17,7 @@ obj-$(CONFIG_XEN_FRAMEBUFFER)         += fbfron
 obj-$(CONFIG_XEN_FRAMEBUFFER)          += fbfront/
 obj-$(CONFIG_XEN_KEYBOARD)             += fbfront/
 obj-$(CONFIG_XEN_SCSI_BACKEND)         += scsiback/
+obj-$(CONFIG_XEN_SCSI_FRONTEND)                += scsifront/
 obj-$(CONFIG_XEN_PRIVCMD)      += privcmd/
 obj-$(CONFIG_XEN_GRANT_DEV)    += gntdev/
 obj-$(CONFIG_XEN_NETDEV_ACCEL_SFC_UTIL)                += sfc_netutil/
diff -r 66faefe721eb -r 3b3701ad4eec drivers/xen/scsifront/Makefile
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/drivers/xen/scsifront/Makefile    Mon Jun 02 09:58:56 2008 +0100
@@ -0,0 +1,3 @@
+
+obj-$(CONFIG_XEN_SCSI_FRONTEND)        := xenscsi.o
+xenscsi-objs := scsifront.o xenbus.o
diff -r 66faefe721eb -r 3b3701ad4eec drivers/xen/scsifront/common.h
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/drivers/xen/scsifront/common.h    Mon Jun 02 09:58:56 2008 +0100
@@ -0,0 +1,132 @@
+/*
+ * Xen SCSI frontend driver
+ *
+ * Copyright (c) 2008, FUJITSU Limited
+ *
+ * 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.
+ */
+
+#ifndef __XEN_DRIVERS_SCSIFRONT_H__
+#define __XEN_DRIVERS_SCSIFRONT_H__
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/kthread.h>
+#include <linux/wait.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include <linux/blkdev.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+#include <xen/xenbus.h>
+#include <xen/gnttab.h>
+#include <xen/evtchn.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/io/ring.h>
+#include <xen/interface/io/vscsiif.h>
+#include <asm/delay.h>
+
+
+#define GRANT_INVALID_REF      0
+#define VSCSI_IN_ABORT         1
+#define VSCSI_IN_RESET         2
+
+/* tuning point*/
+#define VSCSIIF_DEFAULT_CMD_PER_LUN 10
+#define VSCSIIF_MAX_TARGET          64
+#define VSCSIIF_MAX_LUN             255
+
+#define VSCSIIF_RING_SIZE      \
+    __RING_SIZE((struct vscsiif_sring *)0, PAGE_SIZE)
+#define VSCSIIF_MAX_REQS       VSCSIIF_RING_SIZE
+
+struct vscsifrnt_shadow {
+       uint16_t next_free;
+       
+       /* command between backend and frontend
+        * VSCSIIF_ACT_SCSI_CDB or VSCSIIF_ACT_SCSI_RESET */
+       unsigned char act;
+       
+       /* do reset function */
+       wait_queue_head_t wq_reset;     /* reset work queue           */
+       int wait_reset;                 /* reset work queue condition */
+       int32_t rslt_reset;             /* reset response status      */
+                                       /* (SUCESS or FAILED)         */
+
+       /* for DMA_TO_DEVICE(1), DMA_FROM_DEVICE(2), DMA_NONE(3) 
+          requests */
+       unsigned int sc_data_direction;
+       
+       /* Number of pieces of scatter-gather */
+       unsigned int nr_segments;
+
+       /* requested struct scsi_cmnd is stored from kernel */
+       unsigned long req_scsi_cmnd;
+       int gref[VSCSIIF_SG_TABLESIZE];
+};
+
+struct vscsifrnt_info {
+       struct xenbus_device *dev;
+
+       struct Scsi_Host *host;
+
+       spinlock_t io_lock;
+       spinlock_t shadow_lock;
+       unsigned int evtchn;
+       unsigned int irq;
+
+       grant_ref_t ring_ref;
+       struct vscsiif_front_ring ring;
+       struct vscsiif_response ring_res;
+
+       struct vscsifrnt_shadow shadow[VSCSIIF_MAX_REQS];
+       uint32_t shadow_free;
+
+       struct task_struct *kthread;
+       wait_queue_head_t wq;
+       unsigned int waiting_resp;
+       
+       /* abort reset condition bit*/
+       atomic_t abort_reset_cond;
+
+};
+
+#define DPRINTK(_f, _a...)                             \
+       pr_debug("(file=%s, line=%d) " _f,      \
+                __FILE__ , __LINE__ , ## _a )
+
+int scsifront_xenbus_init(void);
+void scsifront_xenbus_unregister(void);
+int scsifront_schedule(void *data);
+irqreturn_t scsifront_intr(int irq, void *dev_id, struct pt_regs *ptregs);
+int scsifront_cmd_done(struct vscsifrnt_info *info);
+
+
+#endif /* __XEN_DRIVERS_SCSIFRONT_H__  */
diff -r 66faefe721eb -r 3b3701ad4eec drivers/xen/scsifront/scsifront.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/drivers/xen/scsifront/scsifront.c Mon Jun 02 09:58:56 2008 +0100
@@ -0,0 +1,519 @@
+/*
+ * Xen SCSI frontend driver
+ *
+ * Copyright (c) 2008, FUJITSU Limited
+ *
+ * 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.
+ */
+ 
+
+#include <linux/version.h>
+#include "common.h"
+
+static int get_id_from_freelist(struct vscsifrnt_info *info)
+{
+       unsigned long flags;
+       uint32_t free;
+
+       spin_lock_irqsave(&info->shadow_lock, flags);
+
+       free = info->shadow_free;
+       BUG_ON(free > VSCSIIF_MAX_REQS);
+       info->shadow_free = info->shadow[free].next_free;
+       info->shadow[free].next_free = 0x0fff;
+
+       info->shadow[free].wait_reset = 0;
+
+       spin_unlock_irqrestore(&info->shadow_lock, flags);
+
+       return free;
+}
+
+static void add_id_to_freelist(struct vscsifrnt_info *info, uint32_t id)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->shadow_lock, flags);
+
+       info->shadow[id].next_free  = info->shadow_free;
+       info->shadow[id].req_scsi_cmnd = 0;
+       info->shadow_free = id;
+
+       spin_unlock_irqrestore(&info->shadow_lock, flags);
+}
+
+
+struct vscsiif_request * scsifront_pre_request(struct vscsifrnt_info *info)
+{
+       struct vscsiif_front_ring *ring = &(info->ring);
+       vscsiif_request_t *ring_req;
+       uint32_t id;
+
+       ring_req = RING_GET_REQUEST(&(info->ring), ring->req_prod_pvt);
+
+       ring->req_prod_pvt++;
+       
+       id = get_id_from_freelist(info);        /* use id by response */
+       ring_req->rqid = (uint16_t)id;
+
+       return ring_req;
+}
+
+
+static void scsifront_notify_work(struct vscsifrnt_info *info)
+{
+       info->waiting_resp = 1;
+       wake_up(&info->wq);
+}
+
+
+static void scsifront_do_request(struct vscsifrnt_info *info)
+{
+       struct vscsiif_front_ring *ring = &(info->ring);
+       unsigned int irq = info->irq;
+       int notify;
+
+       RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(ring, notify);
+       if (notify)
+               notify_remote_via_irq(irq);
+}
+
+irqreturn_t scsifront_intr(int irq, void *dev_id, struct pt_regs *ptregs)
+{
+       scsifront_notify_work((struct vscsifrnt_info *)dev_id);
+       return IRQ_HANDLED;
+}
+
+
+static void scsifront_gnttab_done(struct vscsifrnt_shadow *s, uint32_t id)
+{
+       int i;
+
+       if (s->sc_data_direction == DMA_NONE)
+               return;
+
+       if (s->nr_segments) {
+               for (i = 0; i < s->nr_segments; i++) {
+                       if (unlikely(gnttab_query_foreign_access(
+                               s->gref[i]) != 0)) {
+                               printk(KERN_ALERT "scsifront: "
+                                       "grant still in use by backend.\n");
+                               BUG();
+                       }
+                       gnttab_end_foreign_access(s->gref[i], 0UL);
+               }
+       }
+
+       return;
+}
+
+
+static void scsifront_cdb_cmd_done(struct vscsifrnt_info *info,
+                      vscsiif_response_t *ring_res)
+{
+       struct scsi_cmnd *sc;
+       uint32_t id;
+       uint8_t sense_len;
+
+       id = ring_res->rqid;
+       sc = (struct scsi_cmnd *)info->shadow[id].req_scsi_cmnd;
+
+       if (sc == NULL)
+               BUG();
+
+       scsifront_gnttab_done(&info->shadow[id], id);
+       add_id_to_freelist(info, id);
+
+       rmb();
+       if (atomic_read(&info->abort_reset_cond) == VSCSI_IN_RESET) {
+               sc->result = (DID_RESET << 16);
+       } else {
+               sc->result = ring_res->rslt;
+       }
+
+       sc->resid  = 0;
+
+       if (ring_res->sense_len > VSCSIIF_SENSE_BUFFERSIZE)
+               sense_len = VSCSIIF_SENSE_BUFFERSIZE;
+       else
+               sense_len = ring_res->sense_len;
+
+       if (sense_len)
+               memcpy(sc->sense_buffer, ring_res->sense_buffer, sense_len);
+
+       sc->scsi_done(sc);
+
+       return;
+}
+
+
+static void scsifront_sync_cmd_done(struct vscsifrnt_info *info,
+                               vscsiif_response_t *ring_res)
+{
+       uint16_t id = ring_res->rqid;
+       unsigned long flags;
+       
+       spin_lock_irqsave(&info->shadow_lock, flags);
+       info->shadow[id].wait_reset = 1;
+       info->shadow[id].rslt_reset = ring_res->rslt;
+       spin_unlock_irqrestore(&info->shadow_lock, flags);
+
+       wake_up(&(info->shadow[id].wq_reset));
+}
+
+
+int scsifront_cmd_done(struct vscsifrnt_info *info)
+{
+       vscsiif_response_t *ring_res;
+
+       RING_IDX i, rp;
+       int more_to_do = 0;
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->io_lock, flags);
+
+       rp = info->ring.sring->rsp_prod;
+       rmb();
+       for (i = info->ring.rsp_cons; i != rp; i++) {
+               
+               ring_res = RING_GET_RESPONSE(&info->ring, i);
+
+               if (info->shadow[ring_res->rqid].act == VSCSIIF_ACT_SCSI_CDB)
+                       scsifront_cdb_cmd_done(info, ring_res);
+               else
+                       scsifront_sync_cmd_done(info, ring_res);
+       }
+
+       info->ring.rsp_cons = i;
+
+       if (i != info->ring.req_prod_pvt) {
+               RING_FINAL_CHECK_FOR_RESPONSES(&info->ring, more_to_do);
+       } else {
+               info->ring.sring->rsp_event = i + 1;
+       }
+
+       spin_unlock_irqrestore(&info->io_lock, flags);
+
+       return more_to_do;
+}
+
+
+
+
+int scsifront_schedule(void *data)
+{
+       struct vscsifrnt_info *info = (struct vscsifrnt_info *)data;
+
+       while (!kthread_should_stop()) {
+               wait_event_interruptible(
+                       info->wq,
+                       info->waiting_resp || kthread_should_stop());
+
+               info->waiting_resp = 0;
+               smp_mb();
+
+               if (scsifront_cmd_done(info))
+                       info->waiting_resp = 1;
+       }
+
+       info->kthread = NULL;
+
+       return 0;
+}
+
+
+
+static int map_data_for_request(struct vscsifrnt_info *info,
+               struct scsi_cmnd *sc, vscsiif_request_t *ring_req, uint32_t id)
+{
+       grant_ref_t gref_head;
+       struct page *page;
+       int err, i, ref, ref_cnt = 0;
+       int write = (sc->sc_data_direction == DMA_TO_DEVICE);
+       int nr_pages, off, len, bytes;
+       unsigned long buffer_pfn;
+       unsigned int data_len = 0;
+
+       if (sc->sc_data_direction == DMA_NONE)
+               return 0;
+
+       err = gnttab_alloc_grant_references(VSCSIIF_SG_TABLESIZE, &gref_head);
+       if (err) {
+               printk(KERN_ERR "scsifront: gnttab_alloc_grant_references() 
error\n");
+               return -ENOMEM;
+       }
+
+       if (sc->use_sg) {
+               /* quoted scsi_lib.c/scsi_req_map_sg . */
+               struct scatterlist *sg = (struct scatterlist 
*)sc->request_buffer;
+               nr_pages = (sc->request_bufflen + sg[0].offset + PAGE_SIZE - 1) 
>> PAGE_SHIFT;
+
+               if (nr_pages > VSCSIIF_SG_TABLESIZE) {
+                       printk(KERN_ERR "scsifront: Unable to map 
request_buffer for command!\n");
+                       ref_cnt = (-E2BIG);
+                       goto big_to_sg;
+               }
+
+               for (i = 0; i < sc->use_sg; i++) {
+                       page = sg[i].page;
+                       off = sg[i].offset;
+                       len = sg[i].length;
+                       data_len += len;
+
+                       buffer_pfn = page_to_phys(page) >> PAGE_SHIFT;
+
+                       while (len > 0) {
+                               bytes = min_t(unsigned int, len, PAGE_SIZE - 
off);
+                               
+                               ref = gnttab_claim_grant_reference(&gref_head);
+                               BUG_ON(ref == -ENOSPC);
+
+                               gnttab_grant_foreign_access_ref(ref, 
info->dev->otherend_id,
+                                       buffer_pfn, write);
+
+                               info->shadow[id].gref[ref_cnt]  = ref;
+                               ring_req->seg[ref_cnt].gref     = ref;
+                               ring_req->seg[ref_cnt].offset   = (uint16_t)off;
+                               ring_req->seg[ref_cnt].length   = 
(uint16_t)bytes;
+
+                               buffer_pfn++;
+                               len -= bytes;
+                               off = 0;
+                               ref_cnt++;
+                       }
+               }
+       } else if (sc->request_bufflen) {
+               unsigned long end   = ((unsigned long)sc->request_buffer
+                                       + sc->request_bufflen + PAGE_SIZE - 1) 
>> PAGE_SHIFT;
+               unsigned long start = (unsigned long)sc->request_buffer >> 
PAGE_SHIFT;
+
+               page = virt_to_page(sc->request_buffer);
+               nr_pages = end - start;
+               len = sc->request_bufflen;
+
+               if (nr_pages > VSCSIIF_SG_TABLESIZE) {
+                       ref_cnt = (-E2BIG);
+                       goto big_to_sg;
+               }
+
+               buffer_pfn = page_to_phys(page) >> PAGE_SHIFT;
+
+               off = offset_in_page((unsigned long)sc->request_buffer);
+               for (i = 0; i < nr_pages; i++) {
+                       bytes = PAGE_SIZE - off;
+
+                       if (bytes > len)
+                               bytes = len;
+
+                       ref = gnttab_claim_grant_reference(&gref_head);
+                       BUG_ON(ref == -ENOSPC);
+
+                       gnttab_grant_foreign_access_ref(ref, 
info->dev->otherend_id,
+                               buffer_pfn, write);
+
+                       info->shadow[id].gref[i] = ref;
+                       ring_req->seg[i].gref     = ref;
+                       ring_req->seg[i].offset   = (uint16_t)off;
+                       ring_req->seg[i].length   = (uint16_t)bytes;
+
+                       buffer_pfn++;
+                       len -= bytes;
+                       off = 0;
+                       ref_cnt++;
+               }
+       }
+
+big_to_sg:
+
+       gnttab_free_grant_references(gref_head);
+
+       return ref_cnt;
+}
+
+static int scsifront_queuecommand(struct scsi_cmnd *sc,
+                                 void (*done)(struct scsi_cmnd *))
+{
+       struct vscsifrnt_info *info =
+               (struct vscsifrnt_info *) sc->device->host->hostdata;
+       vscsiif_request_t *ring_req;
+       int ref_cnt;
+       uint16_t rqid;
+
+       if (RING_FULL(&info->ring)) {
+               goto out_host_busy;
+       }
+
+       sc->scsi_done = done;
+       sc->result    = 0;
+
+       ring_req          = scsifront_pre_request(info);
+       rqid              = ring_req->rqid;
+       ring_req->act     = VSCSIIF_ACT_SCSI_CDB;
+
+       ring_req->id      = sc->device->id;
+       ring_req->lun     = sc->device->lun;
+       ring_req->channel = sc->device->channel;
+       ring_req->cmd_len = sc->cmd_len;
+
+       BUG_ON(sc->cmd_len > VSCSIIF_MAX_COMMAND_SIZE);
+
+       if ( sc->cmd_len )
+               memcpy(ring_req->cmnd, sc->cmnd, sc->cmd_len);
+       else
+               memset(ring_req->cmnd, 0, VSCSIIF_MAX_COMMAND_SIZE);
+
+       ring_req->sc_data_direction   = (uint8_t)sc->sc_data_direction;
+       ring_req->timeout_per_command = (sc->timeout_per_command / HZ);
+
+       info->shadow[rqid].req_scsi_cmnd     = (unsigned long)sc;
+       info->shadow[rqid].sc_data_direction = sc->sc_data_direction;
+       info->shadow[rqid].act               = ring_req->act;
+
+       ref_cnt = map_data_for_request(info, sc, ring_req, rqid);
+       if (ref_cnt < 0) {
+               add_id_to_freelist(info, rqid);
+               if (ref_cnt == (-ENOMEM))
+                       goto out_host_busy;
+               else {
+                       sc->result = (DID_ERROR << 16);
+                       goto out_fail_command;
+               }
+       }
+
+       ring_req->nr_segments          = (uint8_t)ref_cnt;
+       info->shadow[rqid].nr_segments = ref_cnt;
+
+       scsifront_do_request(info);
+
+       return 0;
+
+out_host_busy:
+       return SCSI_MLQUEUE_HOST_BUSY;
+
+out_fail_command:
+       done(sc);
+       return 0;
+}
+
+
+static int scsifront_eh_abort_handler(struct scsi_cmnd *sc)
+{
+       return (FAILED);
+}
+
+/* vscsi supports only device_reset, because it is each of LUNs */
+static int scsifront_dev_reset_handler(struct scsi_cmnd *sc)
+{
+       struct Scsi_Host *host = sc->device->host;
+       struct vscsifrnt_info *info =
+               (struct vscsifrnt_info *) sc->device->host->hostdata;
+
+       vscsiif_request_t *ring_req;
+       int err;
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
+       spin_lock_irq(host->host_lock);
+#endif
+
+       atomic_set(&info->abort_reset_cond, VSCSI_IN_RESET);
+       while (RING_HAS_UNCONSUMED_RESPONSES(&info->ring)) {
+               if (!scsifront_cmd_done(info))
+                       break;
+       }
+
+       ring_req      = scsifront_pre_request(info);
+       ring_req->act = VSCSIIF_ACT_SCSI_RESET;
+
+       info->shadow[ring_req->rqid].act = VSCSIIF_ACT_SCSI_RESET;
+
+       ring_req->channel = sc->device->channel;
+       ring_req->id      = sc->device->id;
+       ring_req->lun     = sc->device->lun;
+       ring_req->cmd_len = sc->cmd_len;
+
+       if ( sc->cmd_len )
+               memcpy(ring_req->cmnd, sc->cmnd, sc->cmd_len);
+       else
+               memset(ring_req->cmnd, 0, VSCSIIF_MAX_COMMAND_SIZE);
+
+       ring_req->sc_data_direction   = (uint8_t)sc->sc_data_direction;
+       ring_req->timeout_per_command = (sc->timeout_per_command / HZ);
+       ring_req->nr_segments         = 0;
+
+       spin_unlock_irq(host->host_lock);
+       scsifront_do_request(info);     
+       wait_event_interruptible(info->shadow[ring_req->rqid].wq_reset,
+                        info->shadow[ring_req->rqid].wait_reset);
+
+       spin_lock_irq(host->host_lock);
+
+       err = info->shadow[ring_req->rqid].rslt_reset;
+       atomic_set(&info->abort_reset_cond, 0);
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
+       spin_unlock_irq(host->host_lock);
+#endif
+
+       return (err);
+}
+
+
+struct scsi_host_template scsifront_sht = {
+       .module                 = THIS_MODULE,
+       .name                   = "Xen SCSI frontend driver",
+       .queuecommand           = scsifront_queuecommand,
+       .eh_abort_handler       = scsifront_eh_abort_handler,
+       .eh_device_reset_handler= scsifront_dev_reset_handler,
+       .cmd_per_lun            = VSCSIIF_DEFAULT_CMD_PER_LUN,
+       .can_queue              = VSCSIIF_MAX_REQS,
+       .this_id                = -1,
+       .sg_tablesize           = VSCSIIF_SG_TABLESIZE,
+       .use_clustering         = DISABLE_CLUSTERING,
+       .proc_name              = "scsifront",
+};
+
+
+static int __init scsifront_init(void)
+{
+       int err;
+
+       if (!is_running_on_xen())
+               return -ENODEV;
+
+       err = scsifront_xenbus_init();
+
+       return err;
+}
+
+static void __exit scsifront_exit(void)
+{
+       scsifront_xenbus_unregister();
+}
+
+module_init(scsifront_init);
+module_exit(scsifront_exit);
+
+MODULE_DESCRIPTION("Xen SCSI frontend driver");
+MODULE_LICENSE("GPL");
diff -r 66faefe721eb -r 3b3701ad4eec drivers/xen/scsifront/xenbus.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/drivers/xen/scsifront/xenbus.c    Mon Jun 02 09:58:56 2008 +0100
@@ -0,0 +1,446 @@
+/*
+ * Xen SCSI frontend driver
+ *
+ * Copyright (c) 2008, FUJITSU Limited
+ *
+ * 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.
+ */
+ 
+
+#include <linux/version.h>
+#include "common.h"
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,11)
+  #define DEFAULT_TASK_COMM_LEN        16
+#else
+  #define DEFAULT_TASK_COMM_LEN        TASK_COMM_LEN
+#endif
+
+extern struct scsi_host_template scsifront_sht;
+
+static void scsifront_free(struct vscsifrnt_info *info)
+{
+       struct Scsi_Host *host = info->host;
+
+       if (scsi_host_get(host) != NULL)
+               scsi_host_put(host);
+
+       if (info->ring_ref != GRANT_INVALID_REF) {
+               gnttab_end_foreign_access(info->ring_ref,
+                                       (unsigned long)info->ring.sring);
+               info->ring_ref = GRANT_INVALID_REF;
+               info->ring.sring = NULL;
+       }
+
+       if (info->irq)
+               unbind_from_irqhandler(info->irq, info);
+       info->irq = 0;
+}
+
+
+static int scsifront_alloc_ring(struct vscsifrnt_info *info)
+{
+       struct xenbus_device *dev = info->dev;
+       struct vscsiif_sring *sring;
+       int err = -ENOMEM;
+
+
+       info->ring_ref = GRANT_INVALID_REF;
+
+       /***** Frontend to Backend ring start *****/
+       sring = (struct vscsiif_sring *) __get_free_page(GFP_KERNEL);
+       if (!sring) {
+               xenbus_dev_fatal(dev, err, "fail to allocate shared ring (Front 
to Back)");
+               return err;
+       }
+       SHARED_RING_INIT(sring);
+       FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE);
+
+       err = xenbus_grant_ring(dev, virt_to_mfn(sring));
+       if (err < 0) {
+               free_page((unsigned long) sring);
+               info->ring.sring = NULL;
+               xenbus_dev_fatal(dev, err, "fail to grant shared ring (Front to 
Back)");
+               goto free_sring;
+       }
+       info->ring_ref = err;
+
+       err = bind_listening_port_to_irqhandler(
+                       dev->otherend_id, scsifront_intr,
+                       SA_SAMPLE_RANDOM, "scsifront", info);
+
+       if (err <= 0) {
+               xenbus_dev_fatal(dev, err, "bind_listening_port_to_irqhandler");
+               goto fail;
+       }
+       info->irq = err;
+
+       return 0;
+fail:
+       /* free resource */
+free_sring:
+       scsifront_free(info);
+
+       return err;
+}
+
+
+static int scsifront_init_ring(struct vscsifrnt_info *info)
+{
+       struct xenbus_device *dev = info->dev;
+       struct xenbus_transaction xbt;
+       int err;
+
+       DPRINTK("%s\n",__FUNCTION__);
+
+       err = scsifront_alloc_ring(info);
+       if (err)
+               return err;
+       DPRINTK("%u %u\n", info->ring_ref, info->evtchn);
+
+again:
+       err = xenbus_transaction_start(&xbt);
+       if (err) {
+               xenbus_dev_fatal(dev, err, "starting transaction");
+       }
+
+       err = xenbus_printf(xbt, dev->nodename, "ring-ref", "%u",
+                               info->ring_ref);
+       if (err) {
+               xenbus_dev_fatal(dev, err, "%s", "writing ring-ref");
+               goto fail;
+       }
+
+       err = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
+                               irq_to_evtchn_port(info->irq));
+
+       if (err) {
+               xenbus_dev_fatal(dev, err, "%s", "writing event-channel");
+               goto fail;
+       }
+
+       err = xenbus_printf(xbt, dev->nodename, "vhostno", "%u",
+                               info->host->host_no);
+       if (err) {
+               xenbus_dev_fatal(dev, err, "%s", "writing vhostno");
+               goto fail;
+       }
+
+       err = xenbus_transaction_end(xbt, 0);
+       if (err) {
+               if (err == -EAGAIN)
+                       goto again;
+               xenbus_dev_fatal(dev, err, "completing transaction");
+       } else
+               xenbus_switch_state(dev, XenbusStateInitialised);
+
+       return 0;
+
+fail:
+       xenbus_transaction_end(xbt, 1);
+       /* free resource */
+       scsifront_free(info);
+       
+       return err;
+}
+
+
+static int scsifront_probe(struct xenbus_device *dev,
+                               const struct xenbus_device_id *id)
+{
+       struct vscsifrnt_info *info;
+       struct Scsi_Host *host;
+       int i, err = -ENOMEM;
+       char name[DEFAULT_TASK_COMM_LEN];
+
+       host = scsi_host_alloc(&scsifront_sht, sizeof(*info));
+       if (!host) {
+               xenbus_dev_fatal(dev, err, "fail to allocate scsi host");
+               return err;
+       }
+       info = (struct vscsifrnt_info *) host->hostdata;
+       info->host = host;
+
+
+       dev->dev.driver_data = info;
+       info->dev  = dev;
+
+       for (i = 0; i < VSCSIIF_MAX_REQS; i++) {
+               info->shadow[i].next_free = i + 1;
+               init_waitqueue_head(&(info->shadow[i].wq_reset));
+               info->shadow[i].wait_reset = 0;
+       }
+       info->shadow[VSCSIIF_MAX_REQS - 1].next_free = 0x0fff;
+
+       atomic_set(&info->abort_reset_cond, 0);
+
+       err = scsifront_init_ring(info);
+       if (err) {
+               scsi_host_put(host);
+               return err;
+       }
+
+       init_waitqueue_head(&info->wq);
+       spin_lock_init(&info->io_lock);
+       spin_lock_init(&info->shadow_lock);
+
+       snprintf(name, DEFAULT_TASK_COMM_LEN, "vscsiif.%d", 
info->host->host_no);
+
+       info->kthread = kthread_run(scsifront_schedule, info, name);
+       if (IS_ERR(info->kthread)) {
+               err = PTR_ERR(info->kthread);
+               info->kthread = NULL;
+       }
+
+       host->max_id      = VSCSIIF_MAX_TARGET;
+       host->max_channel = 0;
+       host->max_lun     = VSCSIIF_MAX_LUN;
+       host->max_sectors = (VSCSIIF_SG_TABLESIZE * PAGE_SIZE / 512);
+
+       err = scsi_add_host(host, &dev->dev);
+       if (err) {
+               printk(KERN_ERR "scsifront: fail to add scsi host %d\n", err);
+               return err;
+       }
+
+       xenbus_switch_state(dev, XenbusStateInitialised);
+
+ #if 0
+       /* All SCSI device scan */
+       scsi_scan_host(host);
+
+       err = xenbus_printf(XBT_NIL, dev->nodename, "hotplug-status", "%s",
+                                                               "connected");
+       if (err) {
+               xenbus_dev_fatal(dev, err, "%s", "writing hotplug-status");
+               return err;
+       }
+ #endif
+       return 0;
+}
+
+static int scsifront_remove(struct xenbus_device *dev)
+{
+       struct vscsifrnt_info *info = dev->dev.driver_data;
+
+       DPRINTK("%s: %s removed\n",__FUNCTION__ ,dev->nodename);
+
+       if (info->kthread) {
+               kthread_stop(info->kthread);
+               info->kthread = NULL;
+       }
+
+       scsifront_free(info);
+       
+       return 0;
+}
+
+
+static int scsifront_disconnect(struct vscsifrnt_info *info)
+{
+       struct xenbus_device *dev = info->dev;
+       struct Scsi_Host *host = info->host;
+
+       unsigned long flags;
+
+       DPRINTK("%s: %s disconnect\n",__FUNCTION__ ,dev->nodename);
+
+       spin_lock_irqsave(host->host_lock, flags);
+       while (RING_HAS_UNCONSUMED_RESPONSES(&info->ring)) {
+               if (!scsifront_cmd_done(info))
+                       break;
+       }
+
+       spin_unlock_irqrestore(host->host_lock, flags);
+
+       spin_lock(&info->io_lock);
+
+       scsi_remove_host(host);
+       scsi_host_put(host);
+
+       spin_unlock(&info->io_lock);
+
+
+       xenbus_frontend_closed(dev);
+
+       return 0;
+}
+
+#define VSCSIFRONT_OP_ADD_LUN  1
+#define VSCSIFRONT_OP_DEL_LUN  2
+
+static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op)
+{
+       struct xenbus_device *dev = info->dev;
+       int i, err = 0;
+       char str[64], state_str[64];
+       char **dir;
+       unsigned int dir_n = 0;
+       unsigned int device_state;
+       unsigned int hst, chn, tgt, lun;
+       struct scsi_device *sdev;
+
+       dir = xenbus_directory(XBT_NIL, dev->otherend, "vscsi-devs", &dir_n);
+       if (IS_ERR(dir))
+               return;
+
+       for (i = 0; i < dir_n; i++) {
+               /* read status */
+               snprintf(str, sizeof(str), "vscsi-devs/%s/state", dir[i]);
+               err = xenbus_scanf(XBT_NIL, dev->otherend, str, "%u",
+                       &device_state);
+               if (XENBUS_EXIST_ERR(err))
+                       goto fail;
+               
+               /* virtual SCSI device */
+               snprintf(str, sizeof(str), "vscsi-devs/%s/v-dev", dir[i]);
+               err = xenbus_scanf(XBT_NIL, dev->otherend, str,
+                       "%u:%u:%u:%u", &hst, &chn, &tgt, &lun);
+               if (XENBUS_EXIST_ERR(err))
+                       goto fail;
+
+               /* front device state path */
+               snprintf(state_str, sizeof(state_str), "vscsi-devs/%s/state", 
dir[i]);
+
+               switch (op) {
+               case VSCSIFRONT_OP_ADD_LUN:
+                       if (device_state == XenbusStateInitialised) {
+                               sdev = scsi_device_lookup(info->host, chn, tgt, 
lun);
+                               if (sdev) {
+                                       xenbus_printf(XBT_NIL, dev->nodename,
+                                               state_str, "%d", 
XenbusStateClosing);
+                               } else {
+                                       scsi_add_device(info->host, chn, tgt, 
lun);
+                                       xenbus_printf(XBT_NIL, dev->nodename,
+                                               state_str, "%d", 
XenbusStateInitialised);
+                               }
+                       }
+                       break;
+               case VSCSIFRONT_OP_DEL_LUN:
+                       if (device_state == XenbusStateClosing) {
+                               sdev = scsi_device_lookup(info->host, chn, tgt, 
lun);
+                               if (sdev) {
+                                       scsi_remove_device(sdev);
+                                       scsi_device_put(sdev);
+                                       xenbus_printf(XBT_NIL, dev->nodename,
+                                               state_str, "%d", 
XenbusStateClosing);
+                               } else {
+                                       err = PTR_ERR(sdev);
+                                       goto scsi_del_fail;
+                               }
+                       }
+                       break;
+               default:
+                       goto fail;
+                       break;
+               }
+       }
+       
+       kfree(dir);
+       return;
+
+fail:
+       kfree(dir);
+       xenbus_dev_fatal(dev, err, "read or write %s ", str);
+       return;
+
+scsi_del_fail:
+       kfree(dir);
+       printk(KERN_ERR "scsifront: fail to del scsi lun %d\n", err);
+       return;
+
+}
+
+
+
+
+static void scsifront_backend_changed(struct xenbus_device *dev,
+                               enum xenbus_state backend_state)
+{
+       struct vscsifrnt_info *info = dev->dev.driver_data;
+
+       DPRINTK("%p %u %u\n", dev, dev->state, backend_state);
+
+       switch (backend_state) {
+       case XenbusStateUnknown:
+       case XenbusStateInitialising:
+       case XenbusStateInitWait:
+       case XenbusStateClosed:
+               break;
+
+       case XenbusStateInitialised:
+               break;
+
+       case XenbusStateConnected:
+               if (xenbus_read_driver_state(dev->nodename) ==
+                       XenbusStateInitialised) {
+                       scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_ADD_LUN);
+               }
+               xenbus_switch_state(dev, XenbusStateConnected);
+               break;
+
+       case XenbusStateClosing:
+               scsifront_disconnect(info);
+               break;
+
+       case XenbusStateReconfiguring:
+               scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_DEL_LUN);
+               xenbus_switch_state(dev, XenbusStateReconfiguring);
+               break;
+
+       case XenbusStateReconfigured:
+               scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_ADD_LUN);
+               xenbus_switch_state(dev, XenbusStateConnected);
+               break;
+       }
+}
+
+
+static struct xenbus_device_id scsifront_ids[] = {
+       { "vscsi" },
+       { "" }
+};
+
+
+static struct xenbus_driver scsifront_driver = {
+       .name                   = "vscsi",
+       .owner                  = THIS_MODULE,
+       .ids                    = scsifront_ids,
+       .probe                  = scsifront_probe,
+       .remove                 = scsifront_remove,
+/*     .resume                 = scsifront_resume, */
+       .otherend_changed       = scsifront_backend_changed,
+};
+
+int scsifront_xenbus_init(void)
+{
+       return xenbus_register_frontend(&scsifront_driver);
+}
+
+void scsifront_xenbus_unregister(void)
+{
+       xenbus_unregister_driver(&scsifront_driver);
+}
+

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-changelog] [linux-2.6.18-xen] pvSCSI frontend driver, Xen patchbot-linux-2.6.18-xen <=