* [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area
@ 2011-12-20 18:51 K. Y. Srinivasan
2011-12-20 23:06 ` Dan Williams
0 siblings, 1 reply; 6+ messages in thread
From: K. Y. Srinivasan @ 2011-12-20 18:51 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch, linux-scsi
Cc: K. Y. Srinivasan
The storage driver (storvsc_drv.c) handles all block storage devices
assigned to Linux guests hosted on Hyper-V. This driver has been in the
staging tree for a while and this patch moves it out of the staging area.
As per Greg's recommendation, this patch makes no changes to the staging/hv
directory. Once the driver moves out of staging, we will cleanup the
staging/hv directory.
This patch includes all the patches that I have sent against the staging/hv
tree to address the comments I have gotten to date on this storage driver.
Greg has already applied all these patches to the staging tree.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/scsi/Kconfig | 7 +
drivers/scsi/Makefile | 3 +
drivers/scsi/storvsc_drv.c | 1586 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1596 insertions(+), 0 deletions(-)
create mode 100644 drivers/scsi/storvsc_drv.c
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 06ea3bc..4910269 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -662,6 +662,13 @@ config VMWARE_PVSCSI
To compile this driver as a module, choose M here: the
module will be called vmw_pvscsi.
+config HYPERV_STORAGE
+ tristate "Microsoft Hyper-V virtual storage driver"
+ depends on SCSI && HYPERV
+ default HYPERV
+ help
+ Select this option to enable the Hyper-V virtual storage driver.
+
config LIBFC
tristate "LibFC module"
select SCSI_FC_ATTRS
diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 2b88749..e4c1a69 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -142,6 +142,7 @@ obj-$(CONFIG_SCSI_BNX2_ISCSI) += libiscsi.o bnx2i/
obj-$(CONFIG_BE2ISCSI) += libiscsi.o be2iscsi/
obj-$(CONFIG_SCSI_PMCRAID) += pmcraid.o
obj-$(CONFIG_VMWARE_PVSCSI) += vmw_pvscsi.o
+obj-$(CONFIG_HYPERV_STORAGE) += hv_storvsc.o
obj-$(CONFIG_ARM) += arm/
@@ -170,6 +171,8 @@ scsi_mod-$(CONFIG_SCSI_PROC_FS) += scsi_proc.o
scsi_mod-y += scsi_trace.o
scsi_mod-$(CONFIG_PM) += scsi_pm.o
+hv_storvsc-y := storvsc_drv.o
+
scsi_tgt-y += scsi_tgt_lib.o scsi_tgt_if.o
sd_mod-objs := sd.o
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
new file mode 100644
index 0000000..eb853f7
--- /dev/null
+++ b/drivers/scsi/storvsc_drv.c
@@ -0,0 +1,1586 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ * K. Y. Srinivasan <kys@microsoft.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/hyperv.h>
+#include <linux/mempool.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_devinfo.h>
+#include <scsi/scsi_dbg.h>
+
+
+#define STORVSC_MIN_BUF_NR 64
+#define STORVSC_RING_BUFFER_SIZE (20*PAGE_SIZE)
+static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
+
+module_param(storvsc_ringbuffer_size, int, S_IRUGO);
+MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
+
+/* to alert the user that structure sizes may be mismatched even though the */
+/* protocol versions match. */
+
+
+#define REVISION_STRING(REVISION_) #REVISION_
+#define FILL_VMSTOR_REVISION(RESULT_LVALUE_) \
+ do { \
+ char *revision_string \
+ = REVISION_STRING($Rev : 6 $) + 6; \
+ RESULT_LVALUE_ = 0; \
+ while (*revision_string >= '0' \
+ && *revision_string <= '9') { \
+ RESULT_LVALUE_ *= 10; \
+ RESULT_LVALUE_ += *revision_string - '0'; \
+ revision_string++; \
+ } \
+ } while (0)
+
+/* Major/minor macros. Minor version is in LSB, meaning that earlier flat */
+/* version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1). */
+#define VMSTOR_PROTOCOL_MAJOR(VERSION_) (((VERSION_) >> 8) & 0xff)
+#define VMSTOR_PROTOCOL_MINOR(VERSION_) (((VERSION_)) & 0xff)
+#define VMSTOR_PROTOCOL_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
+ (((MINOR_) & 0xff)))
+#define VMSTOR_INVALID_PROTOCOL_VERSION (-1)
+
+/* Version history: */
+/* V1 Beta 0.1 */
+/* V1 RC < 2008/1/31 1.0 */
+/* V1 RC > 2008/1/31 2.0 */
+#define VMSTOR_PROTOCOL_VERSION_CURRENT VMSTOR_PROTOCOL_VERSION(4, 2)
+
+
+
+
+/* This will get replaced with the max transfer length that is possible on */
+/* the host adapter. */
+/* The max transfer length will be published when we offer a vmbus channel. */
+#define MAX_TRANSFER_LENGTH 0x40000
+#define DEFAULT_PACKET_SIZE (sizeof(struct vmdata_gpa_direct) + \
+ sizeof(struct vstor_packet) + \
+ sizesizeof(u64) * (MAX_TRANSFER_LENGTH / PAGE_SIZE)))
+
+
+/* Packet structure describing virtual storage requests. */
+enum vstor_packet_operation {
+ VSTOR_OPERATION_COMPLETE_IO = 1,
+ VSTOR_OPERATION_REMOVE_DEVICE = 2,
+ VSTOR_OPERATION_EXECUTE_SRB = 3,
+ VSTOR_OPERATION_RESET_LUN = 4,
+ VSTOR_OPERATION_RESET_ADAPTER = 5,
+ VSTOR_OPERATION_RESET_BUS = 6,
+ VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
+ VSTOR_OPERATION_END_INITIALIZATION = 8,
+ VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
+ VSTOR_OPERATION_QUERY_PROPERTIES = 10,
+ VSTOR_OPERATION_ENUMERATE_BUS = 11,
+ VSTOR_OPERATION_MAXIMUM = 11
+};
+
+/*
+ * Platform neutral description of a scsi request -
+ * this remains the same across the write regardless of 32/64 bit
+ * note: it's patterned off the SCSI_PASS_THROUGH structure
+ */
+#define CDB16GENERIC_LENGTH 0x10
+
+#ifndef SENSE_BUFFER_SIZE
+#define SENSE_BUFFER_SIZE 0x12
+#endif
+
+#define MAX_DATA_BUF_LEN_WITH_PADDING 0x14
+
+struct vmscsi_request {
+ unsigned short length;
+ unsigned char srb_status;
+ unsigned char scsi_status;
+
+ unsigned char port_number;
+ unsigned char path_id;
+ unsigned char target_id;
+ unsigned char lun;
+
+ unsigned char cdb_length;
+ unsigned char sense_info_length;
+ unsigned char data_in;
+ unsigned char reserved;
+
+ unsigned int data_transfer_length;
+
+ union {
+ unsigned char cdb[CDB16GENERIC_LENGTH];
+ unsigned char sense_data[SENSE_BUFFER_SIZE];
+ unsigned char reserved_array[MAX_DATA_BUF_LEN_WITH_PADDING];
+ };
+} __attribute((packed));
+
+
+/*
+ * This structure is sent during the intialization phase to get the different
+ * properties of the channel.
+ */
+struct vmstorage_channel_properties {
+ unsigned short protocol_version;
+ unsigned char path_id;
+ unsigned char target_id;
+
+ /* Note: port number is only really known on the client side */
+ unsigned int port_number;
+ unsigned int flags;
+ unsigned int max_transfer_bytes;
+
+ /* This id is unique for each channel and will correspond with */
+ /* vendor specific data in the inquirydata */
+ unsigned long long unique_id;
+} __packed;
+
+/* This structure is sent during the storage protocol negotiations. */
+struct vmstorage_protocol_version {
+ /* Major (MSW) and minor (LSW) version numbers. */
+ unsigned short major_minor;
+
+ /*
+ * Revision number is auto-incremented whenever this file is changed
+ * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
+ * definitely indicate incompatibility--but it does indicate mismatched
+ * builds.
+ */
+ unsigned short revision;
+} __packed;
+
+/* Channel Property Flags */
+#define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
+#define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
+
+struct vstor_packet {
+ /* Requested operation type */
+ enum vstor_packet_operation operation;
+
+ /* Flags - see below for values */
+ unsigned int flags;
+
+ /* Status of the request returned from the server side. */
+ unsigned int status;
+
+ /* Data payload area */
+ union {
+ /*
+ * Structure used to forward SCSI commands from the
+ * client to the server.
+ */
+ struct vmscsi_request vm_srb;
+
+ /* Structure used to query channel properties. */
+ struct vmstorage_channel_properties storage_channel_properties;
+
+ /* Used during version negotiations. */
+ struct vmstorage_protocol_version version;
+ };
+} __packed;
+
+/* Packet flags */
+/*
+ * This flag indicates that the server should send back a completion for this
+ * packet.
+ */
+#define REQUEST_COMPLETION_FLAG 0x1
+
+/* This is the set of flags that the vsc can set in any packets it sends */
+#define VSC_LEGAL_FLAGS (REQUEST_COMPLETION_FLAG)
+
+
+/* Defines */
+
+#define STORVSC_MAX_IO_REQUESTS 128
+
+/*
+ * In Hyper-V, each port/path/target maps to 1 scsi host adapter. In
+ * reality, the path/target is not used (ie always set to 0) so our
+ * scsi host adapter essentially has 1 bus with 1 target that contains
+ * up to 256 luns.
+ */
+#define STORVSC_MAX_LUNS_PER_TARGET 64
+#define STORVSC_MAX_TARGETS 1
+#define STORVSC_MAX_CHANNELS 1
+#define STORVSC_MAX_CMD_LEN 16
+
+/* Matches Windows-end */
+enum storvsc_request_type {
+ WRITE_TYPE,
+ READ_TYPE,
+ UNKNOWN_TYPE,
+};
+
+
+struct hv_storvsc_request {
+ struct hv_device *device;
+
+ /* Synchronize the request/response if needed */
+ struct completion wait_event;
+
+ unsigned char *sense_buffer;
+ void *context;
+ void (*on_io_completion)(struct hv_storvsc_request *request);
+ struct hv_multipage_buffer data_buffer;
+
+ struct vstor_packet vstor_packet;
+};
+
+
+/* A storvsc device is a device object that contains a vmbus channel */
+struct storvsc_device {
+ struct hv_device *device;
+
+ bool destroy;
+ bool drain_notify;
+ atomic_t num_outstanding_req;
+ struct Scsi_Host *host;
+
+ wait_queue_head_t waiting_to_drain;
+
+ /*
+ * Each unique Port/Path/Target represents 1 channel ie scsi
+ * controller. In reality, the pathid, targetid is always 0
+ * and the port is set by us
+ */
+ unsigned int port_number;
+ unsigned char path_id;
+ unsigned char target_id;
+
+ /* Used for vsc/vsp channel reset process */
+ struct hv_storvsc_request init_request;
+ struct hv_storvsc_request reset_request;
+};
+
+struct stor_mem_pools {
+ struct kmem_cache *request_pool;
+ mempool_t *request_mempool;
+};
+
+struct hv_host_device {
+ struct hv_device *dev;
+ unsigned int port;
+ unsigned char path;
+ unsigned char target;
+};
+
+struct storvsc_cmd_request {
+ struct list_head entry;
+ struct scsi_cmnd *cmd;
+
+ unsigned int bounce_sgl_count;
+ struct scatterlist *bounce_sgl;
+
+ struct hv_storvsc_request request;
+};
+
+struct storvsc_scan_work {
+ struct work_struct work;
+ struct Scsi_Host *host;
+ uint lun;
+};
+
+static void storvsc_bus_scan(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ int id, order_id;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ for (id = 0; id < wrk->host->max_id; ++id) {
+ if (wrk->host->reverse_ordering)
+ order_id = wrk->host->max_id - id - 1;
+ else
+ order_id = id;
+
+ scsi_scan_target(&wrk->host->shost_gendev, 0,
+ order_id, SCAN_WILD_CARD, 1);
+ }
+ kfree(wrk);
+}
+
+static void storvsc_remove_lun(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ struct scsi_device *sdev;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ if (!scsi_host_get(wrk->host))
+ goto done;
+
+ sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
+
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ }
+ scsi_host_put(wrk->host);
+
+done:
+ kfree(wrk);
+}
+
+static inline struct storvsc_device *get_out_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (stor_device && stor_device->destroy)
+ stor_device = NULL;
+
+ return stor_device;
+}
+
+
+static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
+{
+ dev->drain_notify = true;
+ wait_event(dev->waiting_to_drain,
+ atomic_read(&dev->num_outstanding_req) == 0);
+ dev->drain_notify = false;
+}
+
+static inline struct storvsc_device *get_in_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (!stor_device)
+ goto get_in_err;
+
+ /*
+ * If the device is being destroyed; allow incoming
+ * traffic only to cleanup outstanding requests.
+ */
+
+ if (stor_device->destroy &&
+ (atomic_read(&stor_device->num_outstanding_req) == 0))
+ stor_device = NULL;
+
+get_in_err:
+ return stor_device;
+
+}
+
+static int storvsc_channel_init(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ struct hv_storvsc_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return -ENODEV;
+
+ request = &stor_device->init_request;
+ vstor_packet = &request->vstor_packet;
+
+ /*
+ * Now, initiate the vsc/vsp initialization protocol on the open
+ * channel
+ */
+ memset(request, 0, sizeof(struct hv_storvsc_request));
+ init_completion(&request->wait_event);
+ vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ /* reuse the packet for version range supported */
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->version.major_minor = VMSTOR_PROTOCOL_VERSION_CURRENT;
+ FILL_VMSTOR_REVISION(vstor_packet->version.revision);
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->storage_channel_properties.port_number =
+ stor_device->port_number;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+ stor_device->path_id = vstor_packet->storage_channel_properties.path_id;
+ stor_device->target_id
+ = vstor_packet->storage_channel_properties.target_id;
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+cleanup:
+ return ret;
+}
+
+static void storvsc_on_io_completion(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *stor_pkt;
+
+ stor_device = hv_get_drvdata(device);
+ stor_pkt = &request->vstor_packet;
+
+ /*
+ * The current SCSI handling on the host side does
+ * not correctly handle:
+ * INQUIRY command with page code parameter set to 0x80
+ * MODE_SENSE command with cmd[2] == 0x1c
+ *
+ * Setup srb and scsi status so this won't be fatal.
+ * We do this so we can distinguish truly fatal failues
+ * (srb status == 0x4) and off-line the device in that case.
+ */
+
+ if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
+ (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
+ vstor_packet->vm_srb.scsi_status = 0;
+ vstor_packet->vm_srb.srb_status = 0x1;
+ }
+
+
+ /* Copy over the status...etc */
+ stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
+ stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
+ stor_pkt->vm_srb.sense_info_length =
+ vstor_packet->vm_srb.sense_info_length;
+
+ if (vstor_packet->vm_srb.scsi_status != 0 ||
+ vstor_packet->vm_srb.srb_status != 1){
+ dev_warn(&device->device,
+ "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
+ stor_pkt->vm_srb.cdb[0],
+ vstor_packet->vm_srb.scsi_status,
+ vstor_packet->vm_srb.srb_status);
+ }
+
+ if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
+ /* CHECK_CONDITION */
+ if (vstor_packet->vm_srb.srb_status & 0x80) {
+ /* autosense data available */
+ dev_warn(&device->device,
+ "stor pkt %p autosense data valid - len %d\n",
+ request,
+ vstor_packet->vm_srb.sense_info_length);
+
+ memcpy(request->sense_buffer,
+ vstor_packet->vm_srb.sense_data,
+ vstor_packet->vm_srb.sense_info_length);
+
+ }
+ }
+
+ stor_pkt->vm_srb.data_transfer_length =
+ vstor_packet->vm_srb.data_transfer_length;
+
+ request->on_io_completion(request);
+
+ if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
+ stor_device->drain_notify)
+ wake_up(&stor_device->waiting_to_drain);
+
+
+}
+
+static void storvsc_on_receive(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_scan_work *work;
+ struct storvsc_device *stor_device;
+
+ switch (vstor_packet->operation) {
+ case VSTOR_OPERATION_COMPLETE_IO:
+ storvsc_on_io_completion(device, vstor_packet, request);
+ break;
+
+ case VSTOR_OPERATION_REMOVE_DEVICE:
+ case VSTOR_OPERATION_ENUMERATE_BUS:
+ stor_device = get_in_stor_device(device);
+ work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
+ if (!work)
+ return;
+
+ INIT_WORK(&work->work, storvsc_bus_scan);
+ work->host = stor_device->host;
+ schedule_work(&work->work);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void storvsc_on_channel_callback(void *context)
+{
+ struct hv_device *device = (struct hv_device *)context;
+ struct storvsc_device *stor_device;
+ u32 bytes_recvd;
+ u64 request_id;
+ unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
+ struct hv_storvsc_request *request;
+ int ret;
+
+
+ stor_device = get_in_stor_device(device);
+ if (!stor_device)
+ return;
+
+ do {
+ ret = vmbus_recvpacket(device->channel, packet,
+ ALIGN(sizeof(struct vstor_packet), 8),
+ &bytes_recvd, &request_id);
+ if (ret == 0 && bytes_recvd > 0) {
+
+ request = (struct hv_storvsc_request *)
+ (unsigned long)request_id;
+
+ if ((request == &stor_device->init_request) ||
+ (request == &stor_device->reset_request)) {
+
+ memcpy(&request->vstor_packet, packet,
+ sizeof(struct vstor_packet));
+ complete(&request->wait_event);
+ } else {
+ storvsc_on_receive(device,
+ (struct vstor_packet *)packet,
+ request);
+ }
+ } else {
+ break;
+ }
+ } while (1);
+
+ return;
+}
+
+static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
+{
+ struct vmstorage_channel_properties props;
+ int ret;
+
+ memset(&props, 0, sizeof(struct vmstorage_channel_properties));
+
+ /* Open the channel */
+ ret = vmbus_open(device->channel,
+ ring_size,
+ ring_size,
+ (void *)&props,
+ sizeof(struct vmstorage_channel_properties),
+ storvsc_on_channel_callback, device);
+
+ if (ret != 0)
+ return ret;
+
+ ret = storvsc_channel_init(device);
+
+ return ret;
+}
+
+static int storvsc_dev_remove(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ unsigned long flags;
+
+ stor_device = hv_get_drvdata(device);
+
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ stor_device->destroy = true;
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /*
+ * At this point, all outbound traffic should be disable. We
+ * only allow inbound traffic (responses) to proceed so that
+ * outstanding requests can be completed.
+ */
+
+ storvsc_wait_to_drain(stor_device);
+
+ /*
+ * Since we have already drained, we don't need to busy wait
+ * as was done in final_release_stor_device()
+ * Note that we cannot set the ext pointer to NULL until
+ * we have drained - to drain the outgoing packets, we need to
+ * allow incoming packets.
+ */
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ hv_set_drvdata(device, NULL);
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /* Close the channel */
+ vmbus_close(device->channel);
+
+ kfree(stor_device);
+ return 0;
+}
+
+static int storvsc_do_io(struct hv_device *device,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *vstor_packet;
+ int ret = 0;
+
+ vstor_packet = &request->vstor_packet;
+ stor_device = get_out_stor_device(device);
+
+ if (!stor_device)
+ return -ENODEV;
+
+
+ request->device = device;
+
+
+ vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
+
+
+ vstor_packet->vm_srb.sense_info_length = SENSE_BUFFER_SIZE;
+
+
+ vstor_packet->vm_srb.data_transfer_length =
+ request->data_buffer.len;
+
+ vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
+
+ if (request->data_buffer.len) {
+ ret = vmbus_sendpacket_multipagebuffer(device->channel,
+ &request->data_buffer,
+ vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request);
+ } else {
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ }
+
+ if (ret != 0)
+ return ret;
+
+ atomic_inc(&stor_device->num_outstanding_req);
+
+ return ret;
+}
+
+static void storvsc_get_ide_info(struct hv_device *dev, int *target, int *path)
+{
+ *target =
+ dev->dev_instance.b[5] << 8 | dev->dev_instance.b[4];
+
+ *path =
+ dev->dev_instance.b[3] << 24 |
+ dev->dev_instance.b[2] << 16 |
+ dev->dev_instance.b[1] << 8 | dev->dev_instance.b[0];
+}
+
+
+static int storvsc_device_alloc(struct scsi_device *sdevice)
+{
+ struct stor_mem_pools *memp;
+ int number = STORVSC_MIN_BUF_NR;
+
+ memp = kzalloc(sizeof(struct stor_mem_pools), GFP_KERNEL);
+ if (!memp)
+ return -ENOMEM;
+
+ memp->request_pool =
+ kmem_cache_create(dev_name(&sdevice->sdev_dev),
+ sizeof(struct storvsc_cmd_request), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+
+ if (!memp->request_pool)
+ goto err0;
+
+ memp->request_mempool = mempool_create(number, mempool_alloc_slab,
+ mempool_free_slab,
+ memp->request_pool);
+
+ if (!memp->request_mempool)
+ goto err1;
+
+ sdevice->hostdata = memp;
+
+ return 0;
+
+err1:
+ kmem_cache_destroy(memp->request_pool);
+
+err0:
+ kfree(memp);
+ return -ENOMEM;
+}
+
+static void storvsc_device_destroy(struct scsi_device *sdevice)
+{
+ struct stor_mem_pools *memp = sdevice->hostdata;
+
+ mempool_destroy(memp->request_mempool);
+ kmem_cache_destroy(memp->request_pool);
+ kfree(memp);
+ sdevice->hostdata = NULL;
+}
+
+static int storvsc_device_configure(struct scsi_device *sdevice)
+{
+ scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
+ STORVSC_MAX_IO_REQUESTS);
+
+ blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
+
+ blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
+
+ return 0;
+}
+
+static void destroy_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count)
+{
+ int i;
+ struct page *page_buf;
+
+ for (i = 0; i < sg_count; i++) {
+ page_buf = sg_page((&sgl[i]));
+ if (page_buf != NULL)
+ __free_page(page_buf);
+ }
+
+ kfree(sgl);
+}
+
+static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
+{
+ int i;
+
+ /* No need to check */
+ if (sg_count < 2)
+ return -1;
+
+ /* We have at least 2 sg entries */
+ for (i = 0; i < sg_count; i++) {
+ if (i == 0) {
+ /* make sure 1st one does not have hole */
+ if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
+ return i;
+ } else if (i == sg_count - 1) {
+ /* make sure last one does not have hole */
+ if (sgl[i].offset != 0)
+ return i;
+ } else {
+ /* make sure no hole in the middle */
+ if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
+ return i;
+ }
+ }
+ return -1;
+}
+
+static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count,
+ unsigned int len,
+ int write)
+{
+ int i;
+ int num_pages;
+ struct scatterlist *bounce_sgl;
+ struct page *page_buf;
+ unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE);
+
+ num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT;
+
+ bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
+ if (!bounce_sgl)
+ return NULL;
+
+ for (i = 0; i < num_pages; i++) {
+ page_buf = alloc_page(GFP_ATOMIC);
+ if (!page_buf)
+ goto cleanup;
+ sg_set_page(&bounce_sgl[i], page_buf, buf_len, 0);
+ }
+
+ return bounce_sgl;
+
+cleanup:
+ destroy_bounce_buffer(bounce_sgl, num_pages);
+ return NULL;
+}
+
+
+/* Assume the original sgl has enough room */
+static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count,
+ unsigned int bounce_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long dest_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
+ dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
+ KM_IRQ0) + orig_sgl[i].offset;
+ dest = dest_addr;
+ destlen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
+ bounce_addr =
+ (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
+ KM_IRQ0);
+
+ while (destlen) {
+ src = bounce_addr + bounce_sgl[j].offset;
+ srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].offset += copylen;
+ destlen -= copylen;
+ dest += copylen;
+
+ if (bounce_sgl[j].offset == bounce_sgl[j].length) {
+ /* full */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ j++;
+
+ /*
+ * It is possible that the number of elements
+ * in the bounce buffer may not be equal to
+ * the number of elements in the original
+ * scatter list. Handle this correctly.
+ */
+
+ if (j == bounce_sgl_count) {
+ /*
+ * We are done; cleanup and return.
+ */
+ kunmap_atomic((void *)(dest_addr -
+ orig_sgl[i].offset),
+ KM_IRQ0);
+ local_irq_restore(flags);
+ return total_copied;
+ }
+
+ /* if we need to use another bounce buffer */
+ if (destlen || i != orig_sgl_count - 1)
+ bounce_addr =
+ (unsigned long)kmap_atomic(
+ sg_page((&bounce_sgl[j])), KM_IRQ0);
+ } else if (destlen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ }
+ }
+
+ kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset),
+ KM_IRQ0);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+
+/* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
+static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long src_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
+ src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
+ KM_IRQ0) + orig_sgl[i].offset;
+ src = src_addr;
+ srclen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
+ bounce_addr =
+ (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
+ KM_IRQ0);
+
+ while (srclen) {
+ /* assume bounce offset always == 0 */
+ dest = bounce_addr + bounce_sgl[j].length;
+ destlen = PAGE_SIZE - bounce_sgl[j].length;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].length += copylen;
+ srclen -= copylen;
+ src += copylen;
+
+ if (bounce_sgl[j].length == PAGE_SIZE) {
+ /* full..move to next entry */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ j++;
+
+ /* if we need to use another bounce buffer */
+ if (srclen || i != orig_sgl_count - 1)
+ bounce_addr =
+ (unsigned long)kmap_atomic(
+ sg_page((&bounce_sgl[j])), KM_IRQ0);
+
+ } else if (srclen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ }
+ }
+
+ kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+
+static int storvsc_remove(struct hv_device *dev)
+{
+ struct storvsc_device *stor_device = hv_get_drvdata(dev);
+ struct Scsi_Host *host = stor_device->host;
+
+ scsi_remove_host(host);
+
+ scsi_host_put(host);
+
+ storvsc_dev_remove(dev);
+
+ return 0;
+}
+
+
+static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
+ sector_t capacity, int *info)
+{
+ sector_t nsect = capacity;
+ sector_t cylinders = nsect;
+ int heads, sectors_pt;
+
+ /*
+ * We are making up these values; let us keep it simple.
+ */
+ heads = 0xff;
+ sectors_pt = 0x3f; /* Sectors per track */
+ sector_div(cylinders, heads * sectors_pt);
+ if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
+ cylinders = 0xffff;
+
+ info[0] = heads;
+ info[1] = sectors_pt;
+ info[2] = (int)cylinders;
+
+ return 0;
+}
+
+static int storvsc_host_reset(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ struct hv_storvsc_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return FAILED;
+
+ request = &stor_device->reset_request;
+ vstor_packet = &request->vstor_packet;
+
+ init_completion(&request->wait_event);
+
+ vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->vm_srb.path_id = stor_device->path_id;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)&stor_device->reset_request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ return FAILED;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0)
+ return TIMEOUT_ERROR;
+
+
+ /*
+ * At this point, all outstanding requests in the adapter
+ * should have been flushed out and return to us
+ */
+
+ return SUCCESS;
+}
+
+
+/*
+ * storvsc_host_reset_handler - Reset the scsi HBA
+ */
+static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
+{
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ struct hv_device *dev = host_dev->dev;
+
+ return storvsc_host_reset(dev);
+}
+
+
+/*
+ * storvsc_command_completion - Command completion processing
+ */
+static void storvsc_command_completion(struct hv_storvsc_request *request)
+{
+ struct storvsc_cmd_request *cmd_request =
+ (struct storvsc_cmd_request *)request->context;
+ struct scsi_cmnd *scmnd = cmd_request->cmd;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ void (*scsi_done_fn)(struct scsi_cmnd *);
+ struct scsi_sense_hdr sense_hdr;
+ struct vmscsi_request *vm_srb;
+ struct storvsc_scan_work *wrk;
+ struct stor_mem_pools *memp = scmnd->device->hostdata;
+
+ vm_srb = &request->vstor_packet.vm_srb;
+ if (cmd_request->bounce_sgl_count) {
+ if (vm_srb->data_in == READ_TYPE)
+ copy_from_bounce_buffer(scsi_sglist(scmnd),
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd),
+ cmd_request->bounce_sgl_count);
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+ }
+
+ /*
+ * If there is an error; offline the device since all
+ * error recovery strategies would have already been
+ * deployed on the host side.
+ */
+ if (vm_srb->srb_status == 0x4)
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ else
+ scmnd->result = vm_srb->scsi_status;
+
+ /*
+ * If the LUN is invalid; remove the device.
+ */
+ if (vm_srb->srb_status == 0x20) {
+ struct storvsc_device *stor_dev;
+ struct hv_device *dev = host_dev->dev;
+ struct Scsi_Host *host;
+
+ stor_dev = get_in_stor_device(dev);
+ host = stor_dev->host;
+
+ wrk = kmalloc(sizeof(struct storvsc_scan_work),
+ GFP_ATOMIC);
+ if (!wrk) {
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ } else {
+ wrk->host = host;
+ wrk->lun = vm_srb->lun;
+ INIT_WORK(&wrk->work, storvsc_remove_lun);
+ schedule_work(&wrk->work);
+ }
+ }
+
+ if (scmnd->result) {
+ if (scsi_normalize_sense(scmnd->sense_buffer,
+ SCSI_SENSE_BUFFERSIZE, &sense_hdr))
+ scsi_print_sense_hdr("storvsc", &sense_hdr);
+ }
+
+ scsi_set_resid(scmnd,
+ request->data_buffer.len -
+ vm_srb->data_transfer_length);
+
+ scsi_done_fn = scmnd->scsi_done;
+
+ scmnd->host_scribble = NULL;
+ scmnd->scsi_done = NULL;
+
+ scsi_done_fn(scmnd);
+
+ mempool_free(cmd_request, memp->request_mempool);
+}
+
+static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
+{
+ bool allowed = true;
+ u8 scsi_op = scmnd->cmnd[0];
+
+ switch (scsi_op) {
+ /* smartd sends this command, which will offline the device */
+ case SET_WINDOW:
+ scmnd->result = ILLEGAL_REQUEST << 16;
+ allowed = false;
+ break;
+ default:
+ break;
+ }
+ return allowed;
+}
+
+/*
+ * storvsc_queuecommand - Initiate command processing
+ */
+static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
+{
+ int ret;
+ struct hv_host_device *host_dev = shost_priv(host);
+ struct hv_device *dev = host_dev->dev;
+ struct hv_storvsc_request *request;
+ struct storvsc_cmd_request *cmd_request;
+ unsigned int request_size = 0;
+ int i;
+ struct scatterlist *sgl;
+ unsigned int sg_count = 0;
+ struct vmscsi_request *vm_srb;
+ struct stor_mem_pools *memp = scmnd->device->hostdata;
+
+ if (storvsc_check_scsi_cmd(scmnd) == false) {
+ scmnd->scsi_done(scmnd);
+ return 0;
+ }
+
+ /* If retrying, no need to prep the cmd */
+ if (scmnd->host_scribble) {
+
+ cmd_request =
+ (struct storvsc_cmd_request *)scmnd->host_scribble;
+
+ goto retry_request;
+ }
+
+ request_size = sizeof(struct storvsc_cmd_request);
+
+ cmd_request = mempool_alloc(memp->request_mempool,
+ GFP_ATOMIC);
+ if (!cmd_request)
+ return SCSI_MLQUEUE_DEVICE_BUSY;
+
+ memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
+
+ /* Setup the cmd request */
+ cmd_request->bounce_sgl_count = 0;
+ cmd_request->bounce_sgl = NULL;
+ cmd_request->cmd = scmnd;
+
+ scmnd->host_scribble = (unsigned char *)cmd_request;
+
+ request = &cmd_request->request;
+ vm_srb = &request->vstor_packet.vm_srb;
+
+
+ /* Build the SRB */
+ switch (scmnd->sc_data_direction) {
+ case DMA_TO_DEVICE:
+ vm_srb->data_in = WRITE_TYPE;
+ break;
+ case DMA_FROM_DEVICE:
+ vm_srb->data_in = READ_TYPE;
+ break;
+ default:
+ vm_srb->data_in = UNKNOWN_TYPE;
+ break;
+ }
+
+ request->on_io_completion = storvsc_command_completion;
+ request->context = cmd_request;/* scmnd; */
+
+ vm_srb->port_number = host_dev->port;
+ vm_srb->path_id = scmnd->device->channel;
+ vm_srb->target_id = scmnd->device->id;
+ vm_srb->lun = scmnd->device->lun;
+
+ vm_srb->cdb_length = scmnd->cmd_len;
+
+ memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
+
+ request->sense_buffer = scmnd->sense_buffer;
+
+
+ request->data_buffer.len = scsi_bufflen(scmnd);
+ if (scsi_sg_count(scmnd)) {
+ sgl = (struct scatterlist *)scsi_sglist(scmnd);
+ sg_count = scsi_sg_count(scmnd);
+
+ /* check if we need to bounce the sgl */
+ if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
+ cmd_request->bounce_sgl =
+ create_bounce_buffer(sgl, scsi_sg_count(scmnd),
+ scsi_bufflen(scmnd),
+ vm_srb->data_in);
+ if (!cmd_request->bounce_sgl) {
+ scmnd->host_scribble = NULL;
+ mempool_free(cmd_request,
+ memp->request_mempool);
+
+ return SCSI_MLQUEUE_HOST_BUSY;
+ }
+
+ cmd_request->bounce_sgl_count =
+ ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >>
+ PAGE_SHIFT;
+
+ if (vm_srb->data_in == WRITE_TYPE)
+ copy_to_bounce_buffer(sgl,
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd));
+
+ sgl = cmd_request->bounce_sgl;
+ sg_count = cmd_request->bounce_sgl_count;
+ }
+
+ request->data_buffer.offset = sgl[0].offset;
+
+ for (i = 0; i < sg_count; i++)
+ request->data_buffer.pfn_array[i] =
+ page_to_pfn(sg_page((&sgl[i])));
+
+ } else if (scsi_sglist(scmnd)) {
+ request->data_buffer.offset =
+ virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
+ request->data_buffer.pfn_array[0] =
+ virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
+ }
+
+retry_request:
+ /* Invokes the vsc to start an IO */
+ ret = storvsc_do_io(dev, &cmd_request->request);
+
+ if (ret == -EAGAIN) {
+ /* no more space */
+
+ if (cmd_request->bounce_sgl_count)
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+
+ mempool_free(cmd_request, memp->request_mempool);
+
+ scmnd->host_scribble = NULL;
+
+ ret = SCSI_MLQUEUE_DEVICE_BUSY;
+ }
+
+ return ret;
+}
+
+/* Scsi driver */
+static struct scsi_host_template scsi_driver = {
+ .module = THIS_MODULE,
+ .name = "storvsc_host_t",
+ .bios_param = storvsc_get_chs,
+ .queuecommand = storvsc_queuecommand,
+ .eh_host_reset_handler = storvsc_host_reset_handler,
+ .slave_alloc = storvsc_device_alloc,
+ .slave_destroy = storvsc_device_destroy,
+ .slave_configure = storvsc_device_configure,
+ .cmd_per_lun = 1,
+ /* 64 max_queue * 1 target */
+ .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS,
+ .this_id = -1,
+ /* no use setting to 0 since ll_blk_rw reset it to 1 */
+ /* currently 32 */
+ .sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT,
+ .use_clustering = DISABLE_CLUSTERING,
+ /* Make sure we dont get a sg segment crosses a page boundary */
+ .dma_boundary = PAGE_SIZE-1,
+};
+
+enum {
+ SCSI_GUID,
+ IDE_GUID,
+};
+
+static const struct hv_vmbus_device_id id_table[] = {
+ /* SCSI guid */
+ { VMBUS_DEVICE(0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
+ 0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f)
+ .driver_data = SCSI_GUID },
+ /* IDE guid */
+ { VMBUS_DEVICE(0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
+ 0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5)
+ .driver_data = IDE_GUID },
+ { },
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+
+/*
+ * storvsc_probe - Add a new device for this driver
+ */
+
+static int storvsc_probe(struct hv_device *device,
+ const struct hv_vmbus_device_id *dev_id)
+{
+ int ret;
+ struct Scsi_Host *host;
+ struct hv_host_device *host_dev;
+ bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
+ int path = 0;
+ int target = 0;
+ struct storvsc_device *stor_device;
+
+ host = scsi_host_alloc(&scsi_driver,
+ sizeof(struct hv_host_device));
+ if (!host)
+ return -ENOMEM;
+
+ host_dev = shost_priv(host);
+ memset(host_dev, 0, sizeof(struct hv_host_device));
+
+ host_dev->port = host->host_no;
+ host_dev->dev = device;
+
+
+ stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
+ if (!stor_device) {
+ ret = -ENOMEM;
+ goto err_out0;
+ }
+
+ stor_device->destroy = false;
+ init_waitqueue_head(&stor_device->waiting_to_drain);
+ stor_device->device = device;
+ stor_device->host = host;
+ hv_set_drvdata(device, stor_device);
+
+ stor_device->port_number = host->host_no;
+ ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
+ if (ret)
+ goto err_out1;
+
+ if (dev_is_ide)
+ storvsc_get_ide_info(device, &target, &path);
+
+ host_dev->path = stor_device->path_id;
+ host_dev->target = stor_device->target_id;
+
+ /* max # of devices per target */
+ host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
+ /* max # of targets per channel */
+ host->max_id = STORVSC_MAX_TARGETS;
+ /* max # of channels */
+ host->max_channel = STORVSC_MAX_CHANNELS - 1;
+ /* max cmd length */
+ host->max_cmd_len = STORVSC_MAX_CMD_LEN;
+
+ /* Register the HBA and start the scsi bus scan */
+ ret = scsi_add_host(host, &device->device);
+ if (ret != 0)
+ goto err_out2;
+
+ if (!dev_is_ide) {
+ scsi_scan_host(host);
+ return 0;
+ }
+ ret = scsi_add_device(host, 0, target, 0);
+ if (ret) {
+ scsi_remove_host(host);
+ goto err_out2;
+ }
+ return 0;
+
+err_out2:
+ /*
+ * Once we have connected with the host, we would need to
+ * to invoke storvsc_dev_remove() to rollback this state and
+ * this call also frees up the stor_device; hence the jump around
+ * err_out1 label.
+ */
+ storvsc_dev_remove(device);
+ goto err_out0;
+
+err_out1:
+ kfree(stor_device);
+
+err_out0:
+ scsi_host_put(host);
+ return ret;
+}
+
+/* The one and only one */
+
+static struct hv_driver storvsc_drv = {
+ .name = KBUILD_MODNAME,
+ .id_table = id_table,
+ .probe = storvsc_probe,
+ .remove = storvsc_remove,
+};
+
+static int __init storvsc_drv_init(void)
+{
+ u32 max_outstanding_req_per_channel;
+
+ /*
+ * Divide the ring buffer data size (which is 1 page less
+ * than the ring buffer size since that page is reserved for
+ * the ring buffer indices) by the max request size (which is
+ * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
+ */
+ max_outstanding_req_per_channel =
+ ((storvsc_ringbuffer_size - PAGE_SIZE) /
+ ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
+ sizeof(struct vstor_packet) + sizeof(u64),
+ sizeof(u64)));
+
+ if (max_outstanding_req_per_channel <
+ STORVSC_MAX_IO_REQUESTS)
+ return -EINVAL;
+
+ return vmbus_driver_register(&storvsc_drv);
+}
+
+static void __exit storvsc_drv_exit(void)
+{
+ vmbus_driver_unregister(&storvsc_drv);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION(HV_DRV_VERSION);
+MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
+module_init(storvsc_drv_init);
+module_exit(storvsc_drv_exit);
--
1.7.4.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area
2011-12-20 18:51 K. Y. Srinivasan
@ 2011-12-20 23:06 ` Dan Williams
2011-12-21 0:42 ` KY Srinivasan
0 siblings, 1 reply; 6+ messages in thread
From: Dan Williams @ 2011-12-20 23:06 UTC (permalink / raw)
To: K. Y. Srinivasan
Cc: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch, linux-scsi
On Tue, Dec 20, 2011 at 10:51 AM, K. Y. Srinivasan <kys@microsoft.com> wrote:
> The storage driver (storvsc_drv.c) handles all block storage devices
> assigned to Linux guests hosted on Hyper-V. This driver has been in the
> staging tree for a while and this patch moves it out of the staging area.
> As per Greg's recommendation, this patch makes no changes to the staging/hv
> directory. Once the driver moves out of staging, we will cleanup the
> staging/hv directory.
>
> This patch includes all the patches that I have sent against the staging/hv
> tree to address the comments I have gotten to date on this storage driver.
> Greg has already applied all these patches to the staging tree.
>
> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
> ---
> drivers/scsi/Kconfig | 7 +
> drivers/scsi/Makefile | 3 +
> drivers/scsi/storvsc_drv.c | 1586 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 1596 insertions(+), 0 deletions(-)
> create mode 100644 drivers/scsi/storvsc_drv.c
Shouldn't this diffstat be something like the following?
drivers/scsi/Kconfig | 7 +
drivers/scsi/Makefile | 3 +
drivers/{staging/hv => scsi}/storvsc_drv.c | 310 +++++++++++++++++++---------
3 files changed, 218 insertions(+), 102 deletions(-)
rename drivers/{staging/hv => scsi}/storvsc_drv.c (87%)
^ permalink raw reply [flat|nested] 6+ messages in thread
* RE: [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area
2011-12-20 23:06 ` Dan Williams
@ 2011-12-21 0:42 ` KY Srinivasan
0 siblings, 0 replies; 6+ messages in thread
From: KY Srinivasan @ 2011-12-21 0:42 UTC (permalink / raw)
To: Dan Williams
Cc: gregkh@suse.de, linux-kernel@vger.kernel.org,
devel@linuxdriverproject.org, virtualization@lists.osdl.org,
ohering@suse.com, James.Bottomley@hansenpartnership.com,
hch@infradead.org, linux-scsi@vger.kernel.org
> -----Original Message-----
> From: dan.j.williams@gmail.com [mailto:dan.j.williams@gmail.com] On Behalf Of
> Dan Williams
> Sent: Tuesday, December 20, 2011 6:06 PM
> To: KY Srinivasan
> Cc: gregkh@suse.de; linux-kernel@vger.kernel.org;
> devel@linuxdriverproject.org; virtualization@lists.osdl.org; ohering@suse.com;
> James.Bottomley@hansenpartnership.com; hch@infradead.org; linux-
> scsi@vger.kernel.org
> Subject: Re: [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver
> out of the staging area
>
> On Tue, Dec 20, 2011 at 10:51 AM, K. Y. Srinivasan <kys@microsoft.com> wrote:
> > The storage driver (storvsc_drv.c) handles all block storage devices
> > assigned to Linux guests hosted on Hyper-V. This driver has been in the
> > staging tree for a while and this patch moves it out of the staging area.
> > As per Greg's recommendation, this patch makes no changes to the staging/hv
> > directory. Once the driver moves out of staging, we will cleanup the
> > staging/hv directory.
> >
> > This patch includes all the patches that I have sent against the staging/hv
> > tree to address the comments I have gotten to date on this storage driver.
> > Greg has already applied all these patches to the staging tree.
> >
> > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
> > ---
> > drivers/scsi/Kconfig | 7 +
> > drivers/scsi/Makefile | 3 +
> > drivers/scsi/storvsc_drv.c | 1586
> ++++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 1596 insertions(+), 0 deletions(-)
> > create mode 100644 drivers/scsi/storvsc_drv.c
>
> Shouldn't this diffstat be something like the following?
>
> drivers/scsi/Kconfig | 7 +
> drivers/scsi/Makefile | 3 +
> drivers/{staging/hv => scsi}/storvsc_drv.c | 310 +++++++++++++++++++---------
> 3 files changed, 218 insertions(+), 102 deletions(-)
> rename drivers/{staging/hv => scsi}/storvsc_drv.c (87%)
As per Greg's suggestion, this patch does not remove the driver from
the staging tree. Once the driver lands in the correct directory, we will
remove the driver from the staging directory.
Regards,
K. Y
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area
@ 2012-01-03 20:27 K. Y. Srinivasan
2012-01-11 10:36 ` Christoph Hellwig
0 siblings, 1 reply; 6+ messages in thread
From: K. Y. Srinivasan @ 2012-01-03 20:27 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch, linux-scsi
Cc: K. Y. Srinivasan
The storage driver (storvsc_drv.c) handles all block storage devices
assigned to Linux guests hosted on Hyper-V. This driver has been in the
staging tree for a while and this patch moves it out of the staging area.
As per Greg's recommendation, this patch makes no changes to the staging/hv
directory. Once the driver moves out of staging, we will cleanup the
staging/hv directory.
This patch includes all the patches that I have sent against the staging/hv
tree to address the comments I have gotten to date on this storage driver.
Greg has already applied all these patches to the staging tree.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/scsi/Kconfig | 7 +
drivers/scsi/Makefile | 3 +
drivers/scsi/storvsc_drv.c | 1586 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1596 insertions(+), 0 deletions(-)
create mode 100644 drivers/scsi/storvsc_drv.c
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 06ea3bc..4910269 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -662,6 +662,13 @@ config VMWARE_PVSCSI
To compile this driver as a module, choose M here: the
module will be called vmw_pvscsi.
+config HYPERV_STORAGE
+ tristate "Microsoft Hyper-V virtual storage driver"
+ depends on SCSI && HYPERV
+ default HYPERV
+ help
+ Select this option to enable the Hyper-V virtual storage driver.
+
config LIBFC
tristate "LibFC module"
select SCSI_FC_ATTRS
diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 2b88749..e4c1a69 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -142,6 +142,7 @@ obj-$(CONFIG_SCSI_BNX2_ISCSI) += libiscsi.o bnx2i/
obj-$(CONFIG_BE2ISCSI) += libiscsi.o be2iscsi/
obj-$(CONFIG_SCSI_PMCRAID) += pmcraid.o
obj-$(CONFIG_VMWARE_PVSCSI) += vmw_pvscsi.o
+obj-$(CONFIG_HYPERV_STORAGE) += hv_storvsc.o
obj-$(CONFIG_ARM) += arm/
@@ -170,6 +171,8 @@ scsi_mod-$(CONFIG_SCSI_PROC_FS) += scsi_proc.o
scsi_mod-y += scsi_trace.o
scsi_mod-$(CONFIG_PM) += scsi_pm.o
+hv_storvsc-y := storvsc_drv.o
+
scsi_tgt-y += scsi_tgt_lib.o scsi_tgt_if.o
sd_mod-objs := sd.o
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
new file mode 100644
index 0000000..eb853f7
--- /dev/null
+++ b/drivers/scsi/storvsc_drv.c
@@ -0,0 +1,1586 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ * K. Y. Srinivasan <kys@microsoft.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/hyperv.h>
+#include <linux/mempool.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_devinfo.h>
+#include <scsi/scsi_dbg.h>
+
+
+#define STORVSC_MIN_BUF_NR 64
+#define STORVSC_RING_BUFFER_SIZE (20*PAGE_SIZE)
+static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
+
+module_param(storvsc_ringbuffer_size, int, S_IRUGO);
+MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
+
+/* to alert the user that structure sizes may be mismatched even though the */
+/* protocol versions match. */
+
+
+#define REVISION_STRING(REVISION_) #REVISION_
+#define FILL_VMSTOR_REVISION(RESULT_LVALUE_) \
+ do { \
+ char *revision_string \
+ = REVISION_STRING($Rev : 6 $) + 6; \
+ RESULT_LVALUE_ = 0; \
+ while (*revision_string >= '0' \
+ && *revision_string <= '9') { \
+ RESULT_LVALUE_ *= 10; \
+ RESULT_LVALUE_ += *revision_string - '0'; \
+ revision_string++; \
+ } \
+ } while (0)
+
+/* Major/minor macros. Minor version is in LSB, meaning that earlier flat */
+/* version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1). */
+#define VMSTOR_PROTOCOL_MAJOR(VERSION_) (((VERSION_) >> 8) & 0xff)
+#define VMSTOR_PROTOCOL_MINOR(VERSION_) (((VERSION_)) & 0xff)
+#define VMSTOR_PROTOCOL_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
+ (((MINOR_) & 0xff)))
+#define VMSTOR_INVALID_PROTOCOL_VERSION (-1)
+
+/* Version history: */
+/* V1 Beta 0.1 */
+/* V1 RC < 2008/1/31 1.0 */
+/* V1 RC > 2008/1/31 2.0 */
+#define VMSTOR_PROTOCOL_VERSION_CURRENT VMSTOR_PROTOCOL_VERSION(4, 2)
+
+
+
+
+/* This will get replaced with the max transfer length that is possible on */
+/* the host adapter. */
+/* The max transfer length will be published when we offer a vmbus channel. */
+#define MAX_TRANSFER_LENGTH 0x40000
+#define DEFAULT_PACKET_SIZE (sizeof(struct vmdata_gpa_direct) + \
+ sizeof(struct vstor_packet) + \
+ sizesizeof(u64) * (MAX_TRANSFER_LENGTH / PAGE_SIZE)))
+
+
+/* Packet structure describing virtual storage requests. */
+enum vstor_packet_operation {
+ VSTOR_OPERATION_COMPLETE_IO = 1,
+ VSTOR_OPERATION_REMOVE_DEVICE = 2,
+ VSTOR_OPERATION_EXECUTE_SRB = 3,
+ VSTOR_OPERATION_RESET_LUN = 4,
+ VSTOR_OPERATION_RESET_ADAPTER = 5,
+ VSTOR_OPERATION_RESET_BUS = 6,
+ VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
+ VSTOR_OPERATION_END_INITIALIZATION = 8,
+ VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
+ VSTOR_OPERATION_QUERY_PROPERTIES = 10,
+ VSTOR_OPERATION_ENUMERATE_BUS = 11,
+ VSTOR_OPERATION_MAXIMUM = 11
+};
+
+/*
+ * Platform neutral description of a scsi request -
+ * this remains the same across the write regardless of 32/64 bit
+ * note: it's patterned off the SCSI_PASS_THROUGH structure
+ */
+#define CDB16GENERIC_LENGTH 0x10
+
+#ifndef SENSE_BUFFER_SIZE
+#define SENSE_BUFFER_SIZE 0x12
+#endif
+
+#define MAX_DATA_BUF_LEN_WITH_PADDING 0x14
+
+struct vmscsi_request {
+ unsigned short length;
+ unsigned char srb_status;
+ unsigned char scsi_status;
+
+ unsigned char port_number;
+ unsigned char path_id;
+ unsigned char target_id;
+ unsigned char lun;
+
+ unsigned char cdb_length;
+ unsigned char sense_info_length;
+ unsigned char data_in;
+ unsigned char reserved;
+
+ unsigned int data_transfer_length;
+
+ union {
+ unsigned char cdb[CDB16GENERIC_LENGTH];
+ unsigned char sense_data[SENSE_BUFFER_SIZE];
+ unsigned char reserved_array[MAX_DATA_BUF_LEN_WITH_PADDING];
+ };
+} __attribute((packed));
+
+
+/*
+ * This structure is sent during the intialization phase to get the different
+ * properties of the channel.
+ */
+struct vmstorage_channel_properties {
+ unsigned short protocol_version;
+ unsigned char path_id;
+ unsigned char target_id;
+
+ /* Note: port number is only really known on the client side */
+ unsigned int port_number;
+ unsigned int flags;
+ unsigned int max_transfer_bytes;
+
+ /* This id is unique for each channel and will correspond with */
+ /* vendor specific data in the inquirydata */
+ unsigned long long unique_id;
+} __packed;
+
+/* This structure is sent during the storage protocol negotiations. */
+struct vmstorage_protocol_version {
+ /* Major (MSW) and minor (LSW) version numbers. */
+ unsigned short major_minor;
+
+ /*
+ * Revision number is auto-incremented whenever this file is changed
+ * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
+ * definitely indicate incompatibility--but it does indicate mismatched
+ * builds.
+ */
+ unsigned short revision;
+} __packed;
+
+/* Channel Property Flags */
+#define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
+#define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
+
+struct vstor_packet {
+ /* Requested operation type */
+ enum vstor_packet_operation operation;
+
+ /* Flags - see below for values */
+ unsigned int flags;
+
+ /* Status of the request returned from the server side. */
+ unsigned int status;
+
+ /* Data payload area */
+ union {
+ /*
+ * Structure used to forward SCSI commands from the
+ * client to the server.
+ */
+ struct vmscsi_request vm_srb;
+
+ /* Structure used to query channel properties. */
+ struct vmstorage_channel_properties storage_channel_properties;
+
+ /* Used during version negotiations. */
+ struct vmstorage_protocol_version version;
+ };
+} __packed;
+
+/* Packet flags */
+/*
+ * This flag indicates that the server should send back a completion for this
+ * packet.
+ */
+#define REQUEST_COMPLETION_FLAG 0x1
+
+/* This is the set of flags that the vsc can set in any packets it sends */
+#define VSC_LEGAL_FLAGS (REQUEST_COMPLETION_FLAG)
+
+
+/* Defines */
+
+#define STORVSC_MAX_IO_REQUESTS 128
+
+/*
+ * In Hyper-V, each port/path/target maps to 1 scsi host adapter. In
+ * reality, the path/target is not used (ie always set to 0) so our
+ * scsi host adapter essentially has 1 bus with 1 target that contains
+ * up to 256 luns.
+ */
+#define STORVSC_MAX_LUNS_PER_TARGET 64
+#define STORVSC_MAX_TARGETS 1
+#define STORVSC_MAX_CHANNELS 1
+#define STORVSC_MAX_CMD_LEN 16
+
+/* Matches Windows-end */
+enum storvsc_request_type {
+ WRITE_TYPE,
+ READ_TYPE,
+ UNKNOWN_TYPE,
+};
+
+
+struct hv_storvsc_request {
+ struct hv_device *device;
+
+ /* Synchronize the request/response if needed */
+ struct completion wait_event;
+
+ unsigned char *sense_buffer;
+ void *context;
+ void (*on_io_completion)(struct hv_storvsc_request *request);
+ struct hv_multipage_buffer data_buffer;
+
+ struct vstor_packet vstor_packet;
+};
+
+
+/* A storvsc device is a device object that contains a vmbus channel */
+struct storvsc_device {
+ struct hv_device *device;
+
+ bool destroy;
+ bool drain_notify;
+ atomic_t num_outstanding_req;
+ struct Scsi_Host *host;
+
+ wait_queue_head_t waiting_to_drain;
+
+ /*
+ * Each unique Port/Path/Target represents 1 channel ie scsi
+ * controller. In reality, the pathid, targetid is always 0
+ * and the port is set by us
+ */
+ unsigned int port_number;
+ unsigned char path_id;
+ unsigned char target_id;
+
+ /* Used for vsc/vsp channel reset process */
+ struct hv_storvsc_request init_request;
+ struct hv_storvsc_request reset_request;
+};
+
+struct stor_mem_pools {
+ struct kmem_cache *request_pool;
+ mempool_t *request_mempool;
+};
+
+struct hv_host_device {
+ struct hv_device *dev;
+ unsigned int port;
+ unsigned char path;
+ unsigned char target;
+};
+
+struct storvsc_cmd_request {
+ struct list_head entry;
+ struct scsi_cmnd *cmd;
+
+ unsigned int bounce_sgl_count;
+ struct scatterlist *bounce_sgl;
+
+ struct hv_storvsc_request request;
+};
+
+struct storvsc_scan_work {
+ struct work_struct work;
+ struct Scsi_Host *host;
+ uint lun;
+};
+
+static void storvsc_bus_scan(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ int id, order_id;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ for (id = 0; id < wrk->host->max_id; ++id) {
+ if (wrk->host->reverse_ordering)
+ order_id = wrk->host->max_id - id - 1;
+ else
+ order_id = id;
+
+ scsi_scan_target(&wrk->host->shost_gendev, 0,
+ order_id, SCAN_WILD_CARD, 1);
+ }
+ kfree(wrk);
+}
+
+static void storvsc_remove_lun(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ struct scsi_device *sdev;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ if (!scsi_host_get(wrk->host))
+ goto done;
+
+ sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
+
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ }
+ scsi_host_put(wrk->host);
+
+done:
+ kfree(wrk);
+}
+
+static inline struct storvsc_device *get_out_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (stor_device && stor_device->destroy)
+ stor_device = NULL;
+
+ return stor_device;
+}
+
+
+static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
+{
+ dev->drain_notify = true;
+ wait_event(dev->waiting_to_drain,
+ atomic_read(&dev->num_outstanding_req) == 0);
+ dev->drain_notify = false;
+}
+
+static inline struct storvsc_device *get_in_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (!stor_device)
+ goto get_in_err;
+
+ /*
+ * If the device is being destroyed; allow incoming
+ * traffic only to cleanup outstanding requests.
+ */
+
+ if (stor_device->destroy &&
+ (atomic_read(&stor_device->num_outstanding_req) == 0))
+ stor_device = NULL;
+
+get_in_err:
+ return stor_device;
+
+}
+
+static int storvsc_channel_init(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ struct hv_storvsc_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return -ENODEV;
+
+ request = &stor_device->init_request;
+ vstor_packet = &request->vstor_packet;
+
+ /*
+ * Now, initiate the vsc/vsp initialization protocol on the open
+ * channel
+ */
+ memset(request, 0, sizeof(struct hv_storvsc_request));
+ init_completion(&request->wait_event);
+ vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ /* reuse the packet for version range supported */
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->version.major_minor = VMSTOR_PROTOCOL_VERSION_CURRENT;
+ FILL_VMSTOR_REVISION(vstor_packet->version.revision);
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->storage_channel_properties.port_number =
+ stor_device->port_number;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+ stor_device->path_id = vstor_packet->storage_channel_properties.path_id;
+ stor_device->target_id
+ = vstor_packet->storage_channel_properties.target_id;
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+cleanup:
+ return ret;
+}
+
+static void storvsc_on_io_completion(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *stor_pkt;
+
+ stor_device = hv_get_drvdata(device);
+ stor_pkt = &request->vstor_packet;
+
+ /*
+ * The current SCSI handling on the host side does
+ * not correctly handle:
+ * INQUIRY command with page code parameter set to 0x80
+ * MODE_SENSE command with cmd[2] == 0x1c
+ *
+ * Setup srb and scsi status so this won't be fatal.
+ * We do this so we can distinguish truly fatal failues
+ * (srb status == 0x4) and off-line the device in that case.
+ */
+
+ if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
+ (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
+ vstor_packet->vm_srb.scsi_status = 0;
+ vstor_packet->vm_srb.srb_status = 0x1;
+ }
+
+
+ /* Copy over the status...etc */
+ stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
+ stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
+ stor_pkt->vm_srb.sense_info_length =
+ vstor_packet->vm_srb.sense_info_length;
+
+ if (vstor_packet->vm_srb.scsi_status != 0 ||
+ vstor_packet->vm_srb.srb_status != 1){
+ dev_warn(&device->device,
+ "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
+ stor_pkt->vm_srb.cdb[0],
+ vstor_packet->vm_srb.scsi_status,
+ vstor_packet->vm_srb.srb_status);
+ }
+
+ if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
+ /* CHECK_CONDITION */
+ if (vstor_packet->vm_srb.srb_status & 0x80) {
+ /* autosense data available */
+ dev_warn(&device->device,
+ "stor pkt %p autosense data valid - len %d\n",
+ request,
+ vstor_packet->vm_srb.sense_info_length);
+
+ memcpy(request->sense_buffer,
+ vstor_packet->vm_srb.sense_data,
+ vstor_packet->vm_srb.sense_info_length);
+
+ }
+ }
+
+ stor_pkt->vm_srb.data_transfer_length =
+ vstor_packet->vm_srb.data_transfer_length;
+
+ request->on_io_completion(request);
+
+ if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
+ stor_device->drain_notify)
+ wake_up(&stor_device->waiting_to_drain);
+
+
+}
+
+static void storvsc_on_receive(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_scan_work *work;
+ struct storvsc_device *stor_device;
+
+ switch (vstor_packet->operation) {
+ case VSTOR_OPERATION_COMPLETE_IO:
+ storvsc_on_io_completion(device, vstor_packet, request);
+ break;
+
+ case VSTOR_OPERATION_REMOVE_DEVICE:
+ case VSTOR_OPERATION_ENUMERATE_BUS:
+ stor_device = get_in_stor_device(device);
+ work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
+ if (!work)
+ return;
+
+ INIT_WORK(&work->work, storvsc_bus_scan);
+ work->host = stor_device->host;
+ schedule_work(&work->work);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void storvsc_on_channel_callback(void *context)
+{
+ struct hv_device *device = (struct hv_device *)context;
+ struct storvsc_device *stor_device;
+ u32 bytes_recvd;
+ u64 request_id;
+ unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
+ struct hv_storvsc_request *request;
+ int ret;
+
+
+ stor_device = get_in_stor_device(device);
+ if (!stor_device)
+ return;
+
+ do {
+ ret = vmbus_recvpacket(device->channel, packet,
+ ALIGN(sizeof(struct vstor_packet), 8),
+ &bytes_recvd, &request_id);
+ if (ret == 0 && bytes_recvd > 0) {
+
+ request = (struct hv_storvsc_request *)
+ (unsigned long)request_id;
+
+ if ((request == &stor_device->init_request) ||
+ (request == &stor_device->reset_request)) {
+
+ memcpy(&request->vstor_packet, packet,
+ sizeof(struct vstor_packet));
+ complete(&request->wait_event);
+ } else {
+ storvsc_on_receive(device,
+ (struct vstor_packet *)packet,
+ request);
+ }
+ } else {
+ break;
+ }
+ } while (1);
+
+ return;
+}
+
+static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
+{
+ struct vmstorage_channel_properties props;
+ int ret;
+
+ memset(&props, 0, sizeof(struct vmstorage_channel_properties));
+
+ /* Open the channel */
+ ret = vmbus_open(device->channel,
+ ring_size,
+ ring_size,
+ (void *)&props,
+ sizeof(struct vmstorage_channel_properties),
+ storvsc_on_channel_callback, device);
+
+ if (ret != 0)
+ return ret;
+
+ ret = storvsc_channel_init(device);
+
+ return ret;
+}
+
+static int storvsc_dev_remove(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ unsigned long flags;
+
+ stor_device = hv_get_drvdata(device);
+
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ stor_device->destroy = true;
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /*
+ * At this point, all outbound traffic should be disable. We
+ * only allow inbound traffic (responses) to proceed so that
+ * outstanding requests can be completed.
+ */
+
+ storvsc_wait_to_drain(stor_device);
+
+ /*
+ * Since we have already drained, we don't need to busy wait
+ * as was done in final_release_stor_device()
+ * Note that we cannot set the ext pointer to NULL until
+ * we have drained - to drain the outgoing packets, we need to
+ * allow incoming packets.
+ */
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ hv_set_drvdata(device, NULL);
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /* Close the channel */
+ vmbus_close(device->channel);
+
+ kfree(stor_device);
+ return 0;
+}
+
+static int storvsc_do_io(struct hv_device *device,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *vstor_packet;
+ int ret = 0;
+
+ vstor_packet = &request->vstor_packet;
+ stor_device = get_out_stor_device(device);
+
+ if (!stor_device)
+ return -ENODEV;
+
+
+ request->device = device;
+
+
+ vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
+
+
+ vstor_packet->vm_srb.sense_info_length = SENSE_BUFFER_SIZE;
+
+
+ vstor_packet->vm_srb.data_transfer_length =
+ request->data_buffer.len;
+
+ vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
+
+ if (request->data_buffer.len) {
+ ret = vmbus_sendpacket_multipagebuffer(device->channel,
+ &request->data_buffer,
+ vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request);
+ } else {
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ }
+
+ if (ret != 0)
+ return ret;
+
+ atomic_inc(&stor_device->num_outstanding_req);
+
+ return ret;
+}
+
+static void storvsc_get_ide_info(struct hv_device *dev, int *target, int *path)
+{
+ *target =
+ dev->dev_instance.b[5] << 8 | dev->dev_instance.b[4];
+
+ *path =
+ dev->dev_instance.b[3] << 24 |
+ dev->dev_instance.b[2] << 16 |
+ dev->dev_instance.b[1] << 8 | dev->dev_instance.b[0];
+}
+
+
+static int storvsc_device_alloc(struct scsi_device *sdevice)
+{
+ struct stor_mem_pools *memp;
+ int number = STORVSC_MIN_BUF_NR;
+
+ memp = kzalloc(sizeof(struct stor_mem_pools), GFP_KERNEL);
+ if (!memp)
+ return -ENOMEM;
+
+ memp->request_pool =
+ kmem_cache_create(dev_name(&sdevice->sdev_dev),
+ sizeof(struct storvsc_cmd_request), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+
+ if (!memp->request_pool)
+ goto err0;
+
+ memp->request_mempool = mempool_create(number, mempool_alloc_slab,
+ mempool_free_slab,
+ memp->request_pool);
+
+ if (!memp->request_mempool)
+ goto err1;
+
+ sdevice->hostdata = memp;
+
+ return 0;
+
+err1:
+ kmem_cache_destroy(memp->request_pool);
+
+err0:
+ kfree(memp);
+ return -ENOMEM;
+}
+
+static void storvsc_device_destroy(struct scsi_device *sdevice)
+{
+ struct stor_mem_pools *memp = sdevice->hostdata;
+
+ mempool_destroy(memp->request_mempool);
+ kmem_cache_destroy(memp->request_pool);
+ kfree(memp);
+ sdevice->hostdata = NULL;
+}
+
+static int storvsc_device_configure(struct scsi_device *sdevice)
+{
+ scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
+ STORVSC_MAX_IO_REQUESTS);
+
+ blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
+
+ blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
+
+ return 0;
+}
+
+static void destroy_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count)
+{
+ int i;
+ struct page *page_buf;
+
+ for (i = 0; i < sg_count; i++) {
+ page_buf = sg_page((&sgl[i]));
+ if (page_buf != NULL)
+ __free_page(page_buf);
+ }
+
+ kfree(sgl);
+}
+
+static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
+{
+ int i;
+
+ /* No need to check */
+ if (sg_count < 2)
+ return -1;
+
+ /* We have at least 2 sg entries */
+ for (i = 0; i < sg_count; i++) {
+ if (i == 0) {
+ /* make sure 1st one does not have hole */
+ if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
+ return i;
+ } else if (i == sg_count - 1) {
+ /* make sure last one does not have hole */
+ if (sgl[i].offset != 0)
+ return i;
+ } else {
+ /* make sure no hole in the middle */
+ if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
+ return i;
+ }
+ }
+ return -1;
+}
+
+static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count,
+ unsigned int len,
+ int write)
+{
+ int i;
+ int num_pages;
+ struct scatterlist *bounce_sgl;
+ struct page *page_buf;
+ unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE);
+
+ num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT;
+
+ bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
+ if (!bounce_sgl)
+ return NULL;
+
+ for (i = 0; i < num_pages; i++) {
+ page_buf = alloc_page(GFP_ATOMIC);
+ if (!page_buf)
+ goto cleanup;
+ sg_set_page(&bounce_sgl[i], page_buf, buf_len, 0);
+ }
+
+ return bounce_sgl;
+
+cleanup:
+ destroy_bounce_buffer(bounce_sgl, num_pages);
+ return NULL;
+}
+
+
+/* Assume the original sgl has enough room */
+static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count,
+ unsigned int bounce_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long dest_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
+ dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
+ KM_IRQ0) + orig_sgl[i].offset;
+ dest = dest_addr;
+ destlen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
+ bounce_addr =
+ (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
+ KM_IRQ0);
+
+ while (destlen) {
+ src = bounce_addr + bounce_sgl[j].offset;
+ srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].offset += copylen;
+ destlen -= copylen;
+ dest += copylen;
+
+ if (bounce_sgl[j].offset == bounce_sgl[j].length) {
+ /* full */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ j++;
+
+ /*
+ * It is possible that the number of elements
+ * in the bounce buffer may not be equal to
+ * the number of elements in the original
+ * scatter list. Handle this correctly.
+ */
+
+ if (j == bounce_sgl_count) {
+ /*
+ * We are done; cleanup and return.
+ */
+ kunmap_atomic((void *)(dest_addr -
+ orig_sgl[i].offset),
+ KM_IRQ0);
+ local_irq_restore(flags);
+ return total_copied;
+ }
+
+ /* if we need to use another bounce buffer */
+ if (destlen || i != orig_sgl_count - 1)
+ bounce_addr =
+ (unsigned long)kmap_atomic(
+ sg_page((&bounce_sgl[j])), KM_IRQ0);
+ } else if (destlen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ }
+ }
+
+ kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset),
+ KM_IRQ0);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+
+/* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
+static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long src_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
+ src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
+ KM_IRQ0) + orig_sgl[i].offset;
+ src = src_addr;
+ srclen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
+ bounce_addr =
+ (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
+ KM_IRQ0);
+
+ while (srclen) {
+ /* assume bounce offset always == 0 */
+ dest = bounce_addr + bounce_sgl[j].length;
+ destlen = PAGE_SIZE - bounce_sgl[j].length;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].length += copylen;
+ srclen -= copylen;
+ src += copylen;
+
+ if (bounce_sgl[j].length == PAGE_SIZE) {
+ /* full..move to next entry */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ j++;
+
+ /* if we need to use another bounce buffer */
+ if (srclen || i != orig_sgl_count - 1)
+ bounce_addr =
+ (unsigned long)kmap_atomic(
+ sg_page((&bounce_sgl[j])), KM_IRQ0);
+
+ } else if (srclen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ }
+ }
+
+ kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+
+static int storvsc_remove(struct hv_device *dev)
+{
+ struct storvsc_device *stor_device = hv_get_drvdata(dev);
+ struct Scsi_Host *host = stor_device->host;
+
+ scsi_remove_host(host);
+
+ scsi_host_put(host);
+
+ storvsc_dev_remove(dev);
+
+ return 0;
+}
+
+
+static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
+ sector_t capacity, int *info)
+{
+ sector_t nsect = capacity;
+ sector_t cylinders = nsect;
+ int heads, sectors_pt;
+
+ /*
+ * We are making up these values; let us keep it simple.
+ */
+ heads = 0xff;
+ sectors_pt = 0x3f; /* Sectors per track */
+ sector_div(cylinders, heads * sectors_pt);
+ if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
+ cylinders = 0xffff;
+
+ info[0] = heads;
+ info[1] = sectors_pt;
+ info[2] = (int)cylinders;
+
+ return 0;
+}
+
+static int storvsc_host_reset(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ struct hv_storvsc_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return FAILED;
+
+ request = &stor_device->reset_request;
+ vstor_packet = &request->vstor_packet;
+
+ init_completion(&request->wait_event);
+
+ vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->vm_srb.path_id = stor_device->path_id;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)&stor_device->reset_request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ return FAILED;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0)
+ return TIMEOUT_ERROR;
+
+
+ /*
+ * At this point, all outstanding requests in the adapter
+ * should have been flushed out and return to us
+ */
+
+ return SUCCESS;
+}
+
+
+/*
+ * storvsc_host_reset_handler - Reset the scsi HBA
+ */
+static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
+{
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ struct hv_device *dev = host_dev->dev;
+
+ return storvsc_host_reset(dev);
+}
+
+
+/*
+ * storvsc_command_completion - Command completion processing
+ */
+static void storvsc_command_completion(struct hv_storvsc_request *request)
+{
+ struct storvsc_cmd_request *cmd_request =
+ (struct storvsc_cmd_request *)request->context;
+ struct scsi_cmnd *scmnd = cmd_request->cmd;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ void (*scsi_done_fn)(struct scsi_cmnd *);
+ struct scsi_sense_hdr sense_hdr;
+ struct vmscsi_request *vm_srb;
+ struct storvsc_scan_work *wrk;
+ struct stor_mem_pools *memp = scmnd->device->hostdata;
+
+ vm_srb = &request->vstor_packet.vm_srb;
+ if (cmd_request->bounce_sgl_count) {
+ if (vm_srb->data_in == READ_TYPE)
+ copy_from_bounce_buffer(scsi_sglist(scmnd),
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd),
+ cmd_request->bounce_sgl_count);
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+ }
+
+ /*
+ * If there is an error; offline the device since all
+ * error recovery strategies would have already been
+ * deployed on the host side.
+ */
+ if (vm_srb->srb_status == 0x4)
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ else
+ scmnd->result = vm_srb->scsi_status;
+
+ /*
+ * If the LUN is invalid; remove the device.
+ */
+ if (vm_srb->srb_status == 0x20) {
+ struct storvsc_device *stor_dev;
+ struct hv_device *dev = host_dev->dev;
+ struct Scsi_Host *host;
+
+ stor_dev = get_in_stor_device(dev);
+ host = stor_dev->host;
+
+ wrk = kmalloc(sizeof(struct storvsc_scan_work),
+ GFP_ATOMIC);
+ if (!wrk) {
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ } else {
+ wrk->host = host;
+ wrk->lun = vm_srb->lun;
+ INIT_WORK(&wrk->work, storvsc_remove_lun);
+ schedule_work(&wrk->work);
+ }
+ }
+
+ if (scmnd->result) {
+ if (scsi_normalize_sense(scmnd->sense_buffer,
+ SCSI_SENSE_BUFFERSIZE, &sense_hdr))
+ scsi_print_sense_hdr("storvsc", &sense_hdr);
+ }
+
+ scsi_set_resid(scmnd,
+ request->data_buffer.len -
+ vm_srb->data_transfer_length);
+
+ scsi_done_fn = scmnd->scsi_done;
+
+ scmnd->host_scribble = NULL;
+ scmnd->scsi_done = NULL;
+
+ scsi_done_fn(scmnd);
+
+ mempool_free(cmd_request, memp->request_mempool);
+}
+
+static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
+{
+ bool allowed = true;
+ u8 scsi_op = scmnd->cmnd[0];
+
+ switch (scsi_op) {
+ /* smartd sends this command, which will offline the device */
+ case SET_WINDOW:
+ scmnd->result = ILLEGAL_REQUEST << 16;
+ allowed = false;
+ break;
+ default:
+ break;
+ }
+ return allowed;
+}
+
+/*
+ * storvsc_queuecommand - Initiate command processing
+ */
+static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
+{
+ int ret;
+ struct hv_host_device *host_dev = shost_priv(host);
+ struct hv_device *dev = host_dev->dev;
+ struct hv_storvsc_request *request;
+ struct storvsc_cmd_request *cmd_request;
+ unsigned int request_size = 0;
+ int i;
+ struct scatterlist *sgl;
+ unsigned int sg_count = 0;
+ struct vmscsi_request *vm_srb;
+ struct stor_mem_pools *memp = scmnd->device->hostdata;
+
+ if (storvsc_check_scsi_cmd(scmnd) == false) {
+ scmnd->scsi_done(scmnd);
+ return 0;
+ }
+
+ /* If retrying, no need to prep the cmd */
+ if (scmnd->host_scribble) {
+
+ cmd_request =
+ (struct storvsc_cmd_request *)scmnd->host_scribble;
+
+ goto retry_request;
+ }
+
+ request_size = sizeof(struct storvsc_cmd_request);
+
+ cmd_request = mempool_alloc(memp->request_mempool,
+ GFP_ATOMIC);
+ if (!cmd_request)
+ return SCSI_MLQUEUE_DEVICE_BUSY;
+
+ memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
+
+ /* Setup the cmd request */
+ cmd_request->bounce_sgl_count = 0;
+ cmd_request->bounce_sgl = NULL;
+ cmd_request->cmd = scmnd;
+
+ scmnd->host_scribble = (unsigned char *)cmd_request;
+
+ request = &cmd_request->request;
+ vm_srb = &request->vstor_packet.vm_srb;
+
+
+ /* Build the SRB */
+ switch (scmnd->sc_data_direction) {
+ case DMA_TO_DEVICE:
+ vm_srb->data_in = WRITE_TYPE;
+ break;
+ case DMA_FROM_DEVICE:
+ vm_srb->data_in = READ_TYPE;
+ break;
+ default:
+ vm_srb->data_in = UNKNOWN_TYPE;
+ break;
+ }
+
+ request->on_io_completion = storvsc_command_completion;
+ request->context = cmd_request;/* scmnd; */
+
+ vm_srb->port_number = host_dev->port;
+ vm_srb->path_id = scmnd->device->channel;
+ vm_srb->target_id = scmnd->device->id;
+ vm_srb->lun = scmnd->device->lun;
+
+ vm_srb->cdb_length = scmnd->cmd_len;
+
+ memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
+
+ request->sense_buffer = scmnd->sense_buffer;
+
+
+ request->data_buffer.len = scsi_bufflen(scmnd);
+ if (scsi_sg_count(scmnd)) {
+ sgl = (struct scatterlist *)scsi_sglist(scmnd);
+ sg_count = scsi_sg_count(scmnd);
+
+ /* check if we need to bounce the sgl */
+ if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
+ cmd_request->bounce_sgl =
+ create_bounce_buffer(sgl, scsi_sg_count(scmnd),
+ scsi_bufflen(scmnd),
+ vm_srb->data_in);
+ if (!cmd_request->bounce_sgl) {
+ scmnd->host_scribble = NULL;
+ mempool_free(cmd_request,
+ memp->request_mempool);
+
+ return SCSI_MLQUEUE_HOST_BUSY;
+ }
+
+ cmd_request->bounce_sgl_count =
+ ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >>
+ PAGE_SHIFT;
+
+ if (vm_srb->data_in == WRITE_TYPE)
+ copy_to_bounce_buffer(sgl,
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd));
+
+ sgl = cmd_request->bounce_sgl;
+ sg_count = cmd_request->bounce_sgl_count;
+ }
+
+ request->data_buffer.offset = sgl[0].offset;
+
+ for (i = 0; i < sg_count; i++)
+ request->data_buffer.pfn_array[i] =
+ page_to_pfn(sg_page((&sgl[i])));
+
+ } else if (scsi_sglist(scmnd)) {
+ request->data_buffer.offset =
+ virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
+ request->data_buffer.pfn_array[0] =
+ virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
+ }
+
+retry_request:
+ /* Invokes the vsc to start an IO */
+ ret = storvsc_do_io(dev, &cmd_request->request);
+
+ if (ret == -EAGAIN) {
+ /* no more space */
+
+ if (cmd_request->bounce_sgl_count)
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+
+ mempool_free(cmd_request, memp->request_mempool);
+
+ scmnd->host_scribble = NULL;
+
+ ret = SCSI_MLQUEUE_DEVICE_BUSY;
+ }
+
+ return ret;
+}
+
+/* Scsi driver */
+static struct scsi_host_template scsi_driver = {
+ .module = THIS_MODULE,
+ .name = "storvsc_host_t",
+ .bios_param = storvsc_get_chs,
+ .queuecommand = storvsc_queuecommand,
+ .eh_host_reset_handler = storvsc_host_reset_handler,
+ .slave_alloc = storvsc_device_alloc,
+ .slave_destroy = storvsc_device_destroy,
+ .slave_configure = storvsc_device_configure,
+ .cmd_per_lun = 1,
+ /* 64 max_queue * 1 target */
+ .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS,
+ .this_id = -1,
+ /* no use setting to 0 since ll_blk_rw reset it to 1 */
+ /* currently 32 */
+ .sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT,
+ .use_clustering = DISABLE_CLUSTERING,
+ /* Make sure we dont get a sg segment crosses a page boundary */
+ .dma_boundary = PAGE_SIZE-1,
+};
+
+enum {
+ SCSI_GUID,
+ IDE_GUID,
+};
+
+static const struct hv_vmbus_device_id id_table[] = {
+ /* SCSI guid */
+ { VMBUS_DEVICE(0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
+ 0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f)
+ .driver_data = SCSI_GUID },
+ /* IDE guid */
+ { VMBUS_DEVICE(0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
+ 0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5)
+ .driver_data = IDE_GUID },
+ { },
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+
+/*
+ * storvsc_probe - Add a new device for this driver
+ */
+
+static int storvsc_probe(struct hv_device *device,
+ const struct hv_vmbus_device_id *dev_id)
+{
+ int ret;
+ struct Scsi_Host *host;
+ struct hv_host_device *host_dev;
+ bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
+ int path = 0;
+ int target = 0;
+ struct storvsc_device *stor_device;
+
+ host = scsi_host_alloc(&scsi_driver,
+ sizeof(struct hv_host_device));
+ if (!host)
+ return -ENOMEM;
+
+ host_dev = shost_priv(host);
+ memset(host_dev, 0, sizeof(struct hv_host_device));
+
+ host_dev->port = host->host_no;
+ host_dev->dev = device;
+
+
+ stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
+ if (!stor_device) {
+ ret = -ENOMEM;
+ goto err_out0;
+ }
+
+ stor_device->destroy = false;
+ init_waitqueue_head(&stor_device->waiting_to_drain);
+ stor_device->device = device;
+ stor_device->host = host;
+ hv_set_drvdata(device, stor_device);
+
+ stor_device->port_number = host->host_no;
+ ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
+ if (ret)
+ goto err_out1;
+
+ if (dev_is_ide)
+ storvsc_get_ide_info(device, &target, &path);
+
+ host_dev->path = stor_device->path_id;
+ host_dev->target = stor_device->target_id;
+
+ /* max # of devices per target */
+ host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
+ /* max # of targets per channel */
+ host->max_id = STORVSC_MAX_TARGETS;
+ /* max # of channels */
+ host->max_channel = STORVSC_MAX_CHANNELS - 1;
+ /* max cmd length */
+ host->max_cmd_len = STORVSC_MAX_CMD_LEN;
+
+ /* Register the HBA and start the scsi bus scan */
+ ret = scsi_add_host(host, &device->device);
+ if (ret != 0)
+ goto err_out2;
+
+ if (!dev_is_ide) {
+ scsi_scan_host(host);
+ return 0;
+ }
+ ret = scsi_add_device(host, 0, target, 0);
+ if (ret) {
+ scsi_remove_host(host);
+ goto err_out2;
+ }
+ return 0;
+
+err_out2:
+ /*
+ * Once we have connected with the host, we would need to
+ * to invoke storvsc_dev_remove() to rollback this state and
+ * this call also frees up the stor_device; hence the jump around
+ * err_out1 label.
+ */
+ storvsc_dev_remove(device);
+ goto err_out0;
+
+err_out1:
+ kfree(stor_device);
+
+err_out0:
+ scsi_host_put(host);
+ return ret;
+}
+
+/* The one and only one */
+
+static struct hv_driver storvsc_drv = {
+ .name = KBUILD_MODNAME,
+ .id_table = id_table,
+ .probe = storvsc_probe,
+ .remove = storvsc_remove,
+};
+
+static int __init storvsc_drv_init(void)
+{
+ u32 max_outstanding_req_per_channel;
+
+ /*
+ * Divide the ring buffer data size (which is 1 page less
+ * than the ring buffer size since that page is reserved for
+ * the ring buffer indices) by the max request size (which is
+ * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
+ */
+ max_outstanding_req_per_channel =
+ ((storvsc_ringbuffer_size - PAGE_SIZE) /
+ ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
+ sizeof(struct vstor_packet) + sizeof(u64),
+ sizeof(u64)));
+
+ if (max_outstanding_req_per_channel <
+ STORVSC_MAX_IO_REQUESTS)
+ return -EINVAL;
+
+ return vmbus_driver_register(&storvsc_drv);
+}
+
+static void __exit storvsc_drv_exit(void)
+{
+ vmbus_driver_unregister(&storvsc_drv);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION(HV_DRV_VERSION);
+MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
+module_init(storvsc_drv_init);
+module_exit(storvsc_drv_exit);
--
1.7.4.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area
2012-01-03 20:27 [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area K. Y. Srinivasan
@ 2012-01-11 10:36 ` Christoph Hellwig
2012-01-12 17:55 ` KY Srinivasan
0 siblings, 1 reply; 6+ messages in thread
From: Christoph Hellwig @ 2012-01-11 10:36 UTC (permalink / raw)
To: K. Y. Srinivasan
Cc: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch, linux-scsi
> +#define STORVSC_MIN_BUF_NR 64
What about a comment explaining what this is for?
> +#define STORVSC_RING_BUFFER_SIZE (20*PAGE_SIZE)
> +static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
I don't think you need the #define here.
> +/* to alert the user that structure sizes may be mismatched even though the */
> +/* protocol versions match. */
> +
> +
> +#define REVISION_STRING(REVISION_) #REVISION_
> +#define FILL_VMSTOR_REVISION(RESULT_LVALUE_) \
> + do { \
> + char *revision_string \
> + = REVISION_STRING($Rev : 6 $) + 6; \
> + RESULT_LVALUE_ = 0; \
> + while (*revision_string >= '0' \
> + && *revision_string <= '9') { \
> + RESULT_LVALUE_ *= 10; \
> + RESULT_LVALUE_ += *revision_string - '0'; \
> + revision_string++; \
> + } \
> + } while (0)
> +
How can these macros work? I don't think git ever expans $Rev, and in
either case I really don't get how this is supposed to work.
> +/* Major/minor macros. Minor version is in LSB, meaning that earlier flat */
> +/* version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1). */
Please use comment formats like this:
/*
* Blah ....
* .....
*/
(this also applies to a few other places).
> +#define VMSTOR_PROTOCOL_MAJOR(VERSION_) (((VERSION_) >> 8) & 0xff)
> +#define VMSTOR_PROTOCOL_MINOR(VERSION_) (((VERSION_)) & 0xff)
> +#define VMSTOR_PROTOCOL_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
> + (((MINOR_) & 0xff)))
All these should be inline functions.
> +#define VMSTOR_INVALID_PROTOCOL_VERSION (-1)
Not used.
> + * Platform neutral description of a scsi request -
> + * this remains the same across the write regardless of 32/64 bit
> + * note: it's patterned off the SCSI_PASS_THROUGH structure
> + */
> +#define CDB16GENERIC_LENGTH 0x10
> +
> +#ifndef SENSE_BUFFER_SIZE
> +#define SENSE_BUFFER_SIZE 0x12
> +#endif
> +
> +#define MAX_DATA_BUF_LEN_WITH_PADDING 0x14
Please don't conditionally re-use the SCSI-layer SENSE_BUFFER_SIZE for
your on the wire packets, but define your own. Please also give all
theses constants a VMSCSI_ or similar prefix.
> +struct vmscsi_request {
> + unsigned short length;
> + unsigned char srb_status;
> + unsigned char scsi_status;
> +
> + unsigned char port_number;
> + unsigned char path_id;
> + unsigned char target_id;
> + unsigned char lun;
> +
> + unsigned char cdb_length;
> + unsigned char sense_info_length;
> + unsigned char data_in;
> + unsigned char reserved;
> +
> + unsigned int data_transfer_length;
> +
> + union {
> + unsigned char cdb[CDB16GENERIC_LENGTH];
> + unsigned char sense_data[SENSE_BUFFER_SIZE];
> + unsigned char reserved_array[MAX_DATA_BUF_LEN_WITH_PADDING];
> + };
> +} __attribute((packed));
Please use fixed size u8/16/32/etc types for all the on-wire defintions.
I'd also really recommend splitting the actual protocol defintion in
a header separate from the driver implementation to make it clear what
is part of the protocol and what's internal to the driver.
> +/* This is the set of flags that the vsc can set in any packets it sends */
> +#define VSC_LEGAL_FLAGS (REQUEST_COMPLETION_FLAG)
unused.
> +#define STORVSC_MAX_CMD_LEN 16
This seems to duplicate the CDB16GENERIC_LENGTH define used above,
please make sure you only have one #define for this constant.
> +
> +/* Matches Windows-end */
> +enum storvsc_request_type {
> + WRITE_TYPE,
> + READ_TYPE,
> + UNKNOWN_TYPE,
> +};
For enums specifying the protocol please always use explicit values.
> +struct hv_storvsc_request {
> + struct hv_device *device;
> +
> + /* Synchronize the request/response if needed */
> + struct completion wait_event;
> +
> + unsigned char *sense_buffer;
> + void *context;
This always is a struct storvsc_cmd_request, and should be typed as
such.
> + void (*on_io_completion)(struct hv_storvsc_request *request);
This always points to storvsc_command_completion, so please remove the
indirect call and use it directly.
> + struct hv_multipage_buffer data_buffer;
> +
> + struct vstor_packet vstor_packet;
> +};
Btw, what is the reason that storvsc_cmd_request and hv_storvsc_request
are separate structures and not merged into one? This wastes a tiny
amount of memory for the init/reset requests, but keeps the code
a lot simpler.
> +static inline struct storvsc_device *get_out_stor_device(
> + struct hv_device *device)
> +static inline struct storvsc_device *get_in_stor_device(
> + struct hv_device *device)
I'm pretty sure you defended this odd reference counting scheme last
time the discussion came up, but please write up a long comment in
the code explaning it so that the question doesn't come up again
all the time.
> + /*
> + * The current SCSI handling on the host side does
> + * not correctly handle:
> + * INQUIRY command with page code parameter set to 0x80
> + * MODE_SENSE command with cmd[2] == 0x1c
> + *
> + * Setup srb and scsi status so this won't be fatal.
> + * We do this so we can distinguish truly fatal failues
> + * (srb status == 0x4) and off-line the device in that case.
> + */
> +
> + if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
> + (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
This should be:
if (stor_pkt->vm_srb.cdb[0] == INQUIRY ||
stor_pkt->vm_srb.cdb[0] == MODE_SENSE) {
or even better use a switch statement to clarify what's going on.
> +static int storvsc_remove(struct hv_device *dev)
> +{
> + struct storvsc_device *stor_device = hv_get_drvdata(dev);
> + struct Scsi_Host *host = stor_device->host;
> +
> + scsi_remove_host(host);
> +
> + scsi_host_put(host);
> +
> + storvsc_dev_remove(dev);
> +
> + return 0;
> +}
Why isn't this near storvcs_probe at the end of the file given that
they logically belong together? Also please only do the scsi_host_put
once you are fully done with it, that is after storvsc_dev_remove.
> +/*
> + * storvsc_host_reset_handler - Reset the scsi HBA
> + */
> +static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
> +{
> + struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
> + struct hv_device *dev = host_dev->dev;
> +
> + return storvsc_host_reset(dev);
> +}
Why is storvsc_host_reset split from this function? Also the comment
really doesn't tell us anything, I'd rather leave it away.
> +/*
> + * storvsc_command_completion - Command completion processing
> + */
> +static void storvsc_command_completion(struct hv_storvsc_request *request)
I really don't see how this comment adds any value over the pure
function name.
> + if (vm_srb->srb_status == 0x4)
> + if (vm_srb->srb_status == 0x20) {
Please add defines for the vm_srb->srb_status values.
> +static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
Please call this storvsc_ignore_command or similar to make the use more
obvious.
> + /* If retrying, no need to prep the cmd */
> + if (scmnd->host_scribble) {
> +
> + cmd_request =
> + (struct storvsc_cmd_request *)scmnd->host_scribble;
> +
> + goto retry_request;
> + }
I don't think this can ever happen given that you make sure to always
clear ->host_scribble when returning SCSI_MLQUEUE_*_BUSY.
> + request_size = sizeof(struct storvsc_cmd_request);
> +
> + cmd_request = mempool_alloc(memp->request_mempool,
> + GFP_ATOMIC);
> + if (!cmd_request)
> + return SCSI_MLQUEUE_DEVICE_BUSY;
The point of the mempool allocator is that it will never return NULL.
> +
> + memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
> +
> + /* Setup the cmd request */
> + cmd_request->bounce_sgl_count = 0;
> + cmd_request->bounce_sgl = NULL;
> + cmd_request->cmd = scmnd;
Either use memset for the whole structure, or set the fields that need
it to 0 explicitly, but not both. I doubt it's more efficient to only
initialise the fields that need it.
> + if (!cmd_request->bounce_sgl) {
> + scmnd->host_scribble = NULL;
> + mempool_free(cmd_request,
> + memp->request_mempool);
> +
> + return SCSI_MLQUEUE_HOST_BUSY;
> + }
> + if (cmd_request->bounce_sgl_count)
> + destroy_bounce_buffer(cmd_request->bounce_sgl,
> + cmd_request->bounce_sgl_count);
> +
> + mempool_free(cmd_request, memp->request_mempool);
> +
> + scmnd->host_scribble = NULL;
> +
> + ret = SCSI_MLQUEUE_DEVICE_BUSY;
Please use goto labels and a single error exit for unwindining on
failure.
> +/* Scsi driver */
Not a useful comment, just remove it.
> +/*
> + * storvsc_probe - Add a new device for this driver
> + */
Not a very useful comment, just remove it.
> + if (dev_is_ide)
> + storvsc_get_ide_info(device, &target, &path);
path is never used, so drop that argument from storvsc_get_ide_info
please. Target is only used in the next dev_is_ide block, so please
move this call to it.
> + /* max # of devices per target */
> + host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
> + /* max # of targets per channel */
> + host->max_id = STORVSC_MAX_TARGETS;
> + /* max # of channels */
> + host->max_channel = STORVSC_MAX_CHANNELS - 1;
> + /* max cmd length */
> + host->max_cmd_len = STORVSC_MAX_CMD_LEN;
Any reason these aren't set directly in the host template?
> + if (!dev_is_ide) {
> + scsi_scan_host(host);
> + return 0;
> + }
> + ret = scsi_add_device(host, 0, target, 0);
> + if (ret) {
> + scsi_remove_host(host);
> + goto err_out2;
> + }
> + return 0;
I'd write this as an if/else block to be be more clear.
> +/* The one and only one */
this isn't an overly useful comment.
^ permalink raw reply [flat|nested] 6+ messages in thread
* RE: [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area
2012-01-11 10:36 ` Christoph Hellwig
@ 2012-01-12 17:55 ` KY Srinivasan
0 siblings, 0 replies; 6+ messages in thread
From: KY Srinivasan @ 2012-01-12 17:55 UTC (permalink / raw)
To: Christoph Hellwig
Cc: gregkh@suse.de, linux-kernel@vger.kernel.org,
devel@linuxdriverproject.org, virtualization@lists.osdl.org,
ohering@suse.com, James.Bottomley@HansenPartnership.com,
linux-scsi@vger.kernel.org
Christoph,
Let me begin by first thanking you for your detailed review. I have addressed all the issues you have
identified - the code looks much better now; thank you! I am currently testing this code and I will post
the patches soon - individual patches against the current code in the staging tree as well as a patch to
move the driver out of staging (as I have done in the past). Please find my responses to your comments
in-line.
Regards,
K. Y
> -----Original Message-----
> From: Christoph Hellwig [mailto:hch@infradead.org]
> Sent: Wednesday, January 11, 2012 5:37 AM
> To: KY Srinivasan
> Cc: gregkh@suse.de; linux-kernel@vger.kernel.org;
> devel@linuxdriverproject.org; virtualization@lists.osdl.org; ohering@suse.com;
> James.Bottomley@HansenPartnership.com; hch@infradead.org; linux-
> scsi@vger.kernel.org
> Subject: Re: [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver
> out of the staging area
>
>
> I'd also really recommend splitting the actual protocol defintion in
> a header separate from the driver implementation to make it clear what
> is part of the protocol and what's internal to the driver.
I have consolidated all of the protocol defines at the start of the file and
these are properly commented. The decision to not have a separate header file
was based on the comments I got from the community a while ago. Hopefully,
this consolidation will address all the concerns.
>
> > +static inline struct storvsc_device *get_out_stor_device(
> > + struct hv_device *device)
>
> > +static inline struct storvsc_device *get_in_stor_device(
> > + struct hv_device *device)
>
> I'm pretty sure you defended this odd reference counting scheme last
> time the discussion came up, but please write up a long comment in
> the code explaning it so that the question doesn't come up again
> all the time.
I don't have any reference counting anymore. I have added a comment
explaining the protocol for managing the life-cycle.
>
> > + request_size = sizeof(struct storvsc_cmd_request);
> > +
> > + cmd_request = mempool_alloc(memp->request_mempool,
> > + GFP_ATOMIC);
> > + if (!cmd_request)
> > + return SCSI_MLQUEUE_DEVICE_BUSY;
>
> The point of the mempool allocator is that it will never return NULL.
With GFP_ATOMIC flag, the allocation I think can fail. At least that is what
mempool_alloc() comment says.
>
> > + /* max # of devices per target */
> > + host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
> > + /* max # of targets per channel */
> > + host->max_id = STORVSC_MAX_TARGETS;
> > + /* max # of channels */
> > + host->max_channel = STORVSC_MAX_CHANNELS - 1;
> > + /* max cmd length */
> > + host->max_cmd_len = STORVSC_MAX_CMD_LEN;
>
> Any reason these aren't set directly in the host template?
This state is not in the scsi_host_template. What am I missing here.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-01-12 17:55 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2012-01-03 20:27 [PATCH 1/1][RESEND] Staging: hv: storvsc: Move the storage driver out of the staging area K. Y. Srinivasan
2012-01-11 10:36 ` Christoph Hellwig
2012-01-12 17:55 ` KY Srinivasan
-- strict thread matches above, loose matches on Subject: below --
2011-12-20 18:51 K. Y. Srinivasan
2011-12-20 23:06 ` Dan Williams
2011-12-21 0:42 ` KY Srinivasan
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