Merge branch 'kmap_atomic' of git://github.com/congwang/linux
[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / scsi / storvsc_drv.c
similarity index 82%
rename from drivers/staging/hv/storvsc_drv.c
rename to drivers/scsi/storvsc_drv.c
index ddbdec8..83a1972 100644 (file)
 #include <scsi/scsi_devinfo.h>
 #include <scsi/scsi_dbg.h>
 
+/*
+ * All wire protocol details (storage protocol between the guest and the host)
+ * are consolidated here.
+ *
+ * Begin protocol definitions.
+ */
 
-#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)
-
-
-
+/*
+ * Version history:
+ * V1 Beta: 0.1
+ * V1 RC < 2008/1/31: 1.0
+ * V1 RC > 2008/1/31:  2.0
+ * Win7: 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)))
+#define VMSTOR_CURRENT_MAJOR  4
+#define VMSTOR_CURRENT_MINOR  2
 
 
 /*  Packet structure describing virtual storage requests. */
@@ -115,35 +82,31 @@ enum vstor_packet_operation {
  * 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
+#define STORVSC_MAX_CMD_LEN                    0x10
+#define STORVSC_SENSE_BUFFER_SIZE              0x12
+#define STORVSC_MAX_BUF_LEN_WITH_PADDING       0x14
 
 struct vmscsi_request {
-       unsigned short length;
-       unsigned char srb_status;
-       unsigned char scsi_status;
+       u16 length;
+       u8 srb_status;
+       u8 scsi_status;
 
-       unsigned char port_number;
-       unsigned char path_id;
-       unsigned char target_id;
-       unsigned char lun;
+       u port_number;
+       u path_id;
+       u target_id;
+       u lun;
 
-       unsigned char cdb_length;
-       unsigned char sense_info_length;
-       unsigned char data_in;
-       unsigned char reserved;
+       u cdb_length;
+       u sense_info_length;
+       u data_in;
+       u reserved;
 
-       unsigned int data_transfer_length;
+       u32 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];
+               u8 cdb[STORVSC_MAX_CMD_LEN];
+               u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
+               u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
        };
 } __attribute((packed));
 
@@ -153,32 +116,36 @@ struct vmscsi_request {
  * properties of the channel.
  */
 struct vmstorage_channel_properties {
-       unsigned short protocol_version;
-       unsigned char path_id;
-       unsigned char target_id;
+       u16 protocol_version;
+       u path_id;
+       u8 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;
+       u32  port_number;
+       u32  flags;
+       u32   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;
+       /*
+        * This id is unique for each channel and will correspond with
+        * vendor specific data in the inquiry data.
+        */
+
+       u64  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;
+       u16 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.
+        * This is only used on the windows side. Just set it to 0.
         */
-       unsigned short revision;
+       u16 revision;
 } __packed;
 
 /* Channel Property Flags */
@@ -190,10 +157,10 @@ struct vstor_packet {
        enum vstor_packet_operation operation;
 
        /*  Flags - see below for values */
-       unsigned int flags;
+       u32 flags;
 
        /* Status of the request returned from the server side. */
-       unsigned int status;
+       u32 status;
 
        /* Data payload area */
        union {
@@ -211,18 +178,47 @@ struct vstor_packet {
        };
 } __packed;
 
-/* Packet flags */
 /*
+ * 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)
+/* Matches Windows-end */
+enum storvsc_request_type {
+       WRITE_TYPE = 0,
+       READ_TYPE,
+       UNKNOWN_TYPE,
+};
+
+/*
+ * SRB status codes and masks; a subset of the codes used here.
+ */
+
+#define SRB_STATUS_AUTOSENSE_VALID     0x80
+#define SRB_STATUS_INVALID_LUN 0x20
+#define SRB_STATUS_SUCCESS     0x01
+#define SRB_STATUS_ERROR       0x04
+
+/*
+ * This is the end of Protocol specific defines.
+ */
+
+
+/*
+ * We setup a mempool to allocate request structures for this driver
+ * on a per-lun basis. The following define specifies the number of
+ * elements in the pool.
+ */
 
+#define STORVSC_MIN_BUF_NR                             64
+static int storvsc_ringbuffer_size = (20 * PAGE_SIZE);
 
-/* Defines */
+module_param(storvsc_ringbuffer_size, int, S_IRUGO);
+MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
 
 #define STORVSC_MAX_IO_REQUESTS                                128
 
@@ -235,27 +231,23 @@ struct vstor_packet {
 #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 storvsc_cmd_request {
+       struct list_head entry;
+       struct scsi_cmnd *cmd;
+
+       unsigned int bounce_sgl_count;
+       struct scatterlist *bounce_sgl;
+
        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;
 };
 
@@ -281,8 +273,8 @@ struct storvsc_device {
        unsigned char target_id;
 
        /* Used for vsc/vsp channel reset process */
-       struct hv_storvsc_request init_request;
-       struct hv_storvsc_request reset_request;
+       struct storvsc_cmd_request init_request;
+       struct storvsc_cmd_request reset_request;
 };
 
 struct stor_mem_pools {
@@ -297,16 +289,6 @@ struct hv_host_device {
        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;
@@ -352,6 +334,34 @@ done:
        kfree(wrk);
 }
 
+/*
+ * 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).
+ */
+
+static inline u16 storvsc_get_version(u8 major, u8 minor)
+{
+       u16 version;
+
+       version = ((major << 8) | minor);
+       return version;
+}
+
+/*
+ * We can get incoming messages from the host that are not in response to
+ * messages that we have sent out. An example of this would be messages
+ * received by the guest to notify dynamic addition/removal of LUNs. To
+ * deal with potential race conditions where the driver may be in the
+ * midst of being unloaded when we might receive an unsolicited message
+ * from the host, we have implemented a mechanism to gurantee sequential
+ * consistency:
+ *
+ * 1) Once the device is marked as being destroyed, we will fail all
+ *    outgoing messages.
+ * 2) We permit incoming messages when the device is being destroyed,
+ *    only to properly account for messages already sent out.
+ */
+
 static inline struct storvsc_device *get_out_stor_device(
                                        struct hv_device *device)
 {
@@ -398,122 +408,348 @@ get_in_err:
 
 }
 
-static int storvsc_channel_init(struct hv_device *device)
+static void destroy_bounce_buffer(struct scatterlist *sgl,
+                                 unsigned int sg_count)
 {
-       struct storvsc_device *stor_device;
-       struct hv_storvsc_request *request;
-       struct vstor_packet *vstor_packet;
-       int ret, t;
+       int i;
+       struct page *page_buf;
 
-       stor_device = get_out_stor_device(device);
-       if (!stor_device)
-               return -ENODEV;
+       for (i = 0; i < sg_count; i++) {
+               page_buf = sg_page((&sgl[i]));
+               if (page_buf != NULL)
+                       __free_page(page_buf);
+       }
 
-       request = &stor_device->init_request;
-       vstor_packet = &request->vstor_packet;
+       kfree(sgl);
+}
 
-       /*
-        * 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;
+static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
+{
+       int i;
 
-       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;
+       /* No need to check */
+       if (sg_count < 2)
+               return -1;
 
-       t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
-       if (t == 0) {
-               ret = -ETIMEDOUT;
-               goto cleanup;
+       /* 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;
+}
 
-       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;
+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);
 
-       vstor_packet->version.major_minor = VMSTOR_PROTOCOL_VERSION_CURRENT;
-       FILL_VMSTOR_REVISION(vstor_packet->version.revision);
+       num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT;
 
-       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;
+       bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
+       if (!bounce_sgl)
+               return NULL;
 
-       t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
-       if (t == 0) {
-               ret = -ETIMEDOUT;
-               goto cleanup;
+       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);
        }
 
-       if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
-           vstor_packet->status != 0)
-               goto cleanup;
-
+       return bounce_sgl;
 
-       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;
+cleanup:
+       destroy_bounce_buffer(bounce_sgl, num_pages);
+       return NULL;
+}
 
-       ret = vmbus_sendpacket(device->channel, vstor_packet,
-                              sizeof(struct vstor_packet),
-                              (unsigned long)request,
-                              VM_PKT_DATA_INBAND,
-                              VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+/* Disgusting wrapper functions */
+static inline unsigned long sg_kmap_atomic(struct scatterlist *sgl, int idx)
+{
+       void *addr = kmap_atomic(sg_page(sgl + idx));
+       return (unsigned long)addr;
+}
 
-       if (ret != 0)
-               goto cleanup;
+static inline void sg_kunmap_atomic(unsigned long addr)
+{
+       kunmap_atomic((void *)addr);
+}
 
-       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;
+/* 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;
 
-       stor_device->path_id = vstor_packet->storage_channel_properties.path_id;
-       stor_device->target_id
-               = vstor_packet->storage_channel_properties.target_id;
+       local_irq_save(flags);
 
-       memset(vstor_packet, 0, sizeof(struct vstor_packet));
-       vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
-       vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+       for (i = 0; i < orig_sgl_count; i++) {
+               dest_addr = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset;
+               dest = dest_addr;
+               destlen = orig_sgl[i].length;
 
-       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 (bounce_addr == 0)
+                       bounce_addr = sg_kmap_atomic(bounce_sgl,j);
 
-       if (ret != 0)
-               goto cleanup;
+               while (destlen) {
+                       src = bounce_addr + bounce_sgl[j].offset;
+                       srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
 
-       t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
-       if (t == 0) {
-               ret = -ETIMEDOUT;
-               goto cleanup;
-       }
+                       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 */
+                               sg_kunmap_atomic(bounce_addr);
+                               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.
+                                        */
+                                       sg_kunmap_atomic(dest_addr - orig_sgl[i].offset);
+                                       local_irq_restore(flags);
+                                       return total_copied;
+                               }
+
+                               /* if we need to use another bounce buffer */
+                               if (destlen || i != orig_sgl_count - 1)
+                                       bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+                       } else if (destlen == 0 && i == orig_sgl_count - 1) {
+                               /* unmap the last bounce that is < PAGE_SIZE */
+                               sg_kunmap_atomic(bounce_addr);
+                       }
+               }
+
+               sg_kunmap_atomic(dest_addr - orig_sgl[i].offset);
+       }
+
+       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 = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset;
+               src = src_addr;
+               srclen = orig_sgl[i].length;
+
+               if (bounce_addr == 0)
+                       bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+
+               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 */
+                               sg_kunmap_atomic(bounce_addr);
+                               j++;
+
+                               /* if we need to use another bounce buffer */
+                               if (srclen || i != orig_sgl_count - 1)
+                                       bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+
+                       } else if (srclen == 0 && i == orig_sgl_count - 1) {
+                               /* unmap the last bounce that is < PAGE_SIZE */
+                               sg_kunmap_atomic(bounce_addr);
+                       }
+               }
+
+               sg_kunmap_atomic(src_addr - orig_sgl[i].offset);
+       }
+
+       local_irq_restore(flags);
+
+       return total_copied;
+}
+
+static int storvsc_channel_init(struct hv_device *device)
+{
+       struct storvsc_device *stor_device;
+       struct storvsc_cmd_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 storvsc_cmd_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 =
+               storvsc_get_version(VMSTOR_CURRENT_MAJOR, VMSTOR_CURRENT_MINOR);
+
+       /*
+        * The revision number is only used in Windows; set it to 0.
+        */
+       vstor_packet->version.revision = 0;
+
+       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)
@@ -524,9 +760,84 @@ cleanup:
        return ret;
 }
 
+
+static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request)
+{
+       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 = &cmd_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 == SRB_STATUS_ERROR)
+               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 == SRB_STATUS_INVALID_LUN) {
+               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,
+               cmd_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 void storvsc_on_io_completion(struct hv_device *device,
                                  struct vstor_packet *vstor_packet,
-                                 struct hv_storvsc_request *request)
+                                 struct storvsc_cmd_request *request)
 {
        struct storvsc_device *stor_device;
        struct vstor_packet *stor_pkt;
@@ -546,9 +857,9 @@ static void storvsc_on_io_completion(struct hv_device *device,
         */
 
        if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
-               (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
+          (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
                vstor_packet->vm_srb.scsi_status = 0;
-               vstor_packet->vm_srb.srb_status = 0x1;
+               vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
        }
 
 
@@ -559,7 +870,7 @@ static void storvsc_on_io_completion(struct hv_device *device,
        vstor_packet->vm_srb.sense_info_length;
 
        if (vstor_packet->vm_srb.scsi_status != 0 ||
-               vstor_packet->vm_srb.srb_status != 1){
+               vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS){
                dev_warn(&device->device,
                         "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
                         stor_pkt->vm_srb.cdb[0],
@@ -569,7 +880,8 @@ static void storvsc_on_io_completion(struct hv_device *device,
 
        if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
                /* CHECK_CONDITION */
-               if (vstor_packet->vm_srb.srb_status & 0x80) {
+               if (vstor_packet->vm_srb.srb_status &
+                       SRB_STATUS_AUTOSENSE_VALID) {
                        /* autosense data available */
                        dev_warn(&device->device,
                                 "stor pkt %p autosense data valid - len %d\n",
@@ -586,7 +898,7 @@ static void storvsc_on_io_completion(struct hv_device *device,
        stor_pkt->vm_srb.data_transfer_length =
        vstor_packet->vm_srb.data_transfer_length;
 
-       request->on_io_completion(request);
+       storvsc_command_completion(request);
 
        if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
                stor_device->drain_notify)
@@ -597,7 +909,7 @@ static void storvsc_on_io_completion(struct hv_device *device,
 
 static void storvsc_on_receive(struct hv_device *device,
                             struct vstor_packet *vstor_packet,
-                            struct hv_storvsc_request *request)
+                            struct storvsc_cmd_request *request)
 {
        struct storvsc_scan_work *work;
        struct storvsc_device *stor_device;
@@ -631,7 +943,7 @@ static void storvsc_on_channel_callback(void *context)
        u32 bytes_recvd;
        u64 request_id;
        unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
-       struct hv_storvsc_request *request;
+       struct storvsc_cmd_request *request;
        int ret;
 
 
@@ -645,7 +957,7 @@ static void storvsc_on_channel_callback(void *context)
                                       &bytes_recvd, &request_id);
                if (ret == 0 && bytes_recvd > 0) {
 
-                       request = (struct hv_storvsc_request *)
+                       request = (struct storvsc_cmd_request *)
                                        (unsigned long)request_id;
 
                        if ((request == &stor_device->init_request) ||
@@ -674,7 +986,6 @@ static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
 
        memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 
-       /* Open the channel */
        ret = vmbus_open(device->channel,
                         ring_size,
                         ring_size,
@@ -728,7 +1039,7 @@ static int storvsc_dev_remove(struct hv_device *device)
 }
 
 static int storvsc_do_io(struct hv_device *device,
-                             struct hv_storvsc_request *request)
+                             struct storvsc_cmd_request *request)
 {
        struct storvsc_device *stor_device;
        struct vstor_packet *vstor_packet;
@@ -749,342 +1060,94 @@ static int storvsc_do_io(struct hv_device *device,
        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])))
-                                       + 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])));
-
-               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);
-                               j++;
+       vstor_packet->vm_srb.sense_info_length = STORVSC_SENSE_BUFFER_SIZE;
 
-                               /*
-                                * 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;
-                               }
+       vstor_packet->vm_srb.data_transfer_length =
+       request->data_buffer.len;
 
-                               /* 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])));
-                       } else if (destlen == 0 && i == orig_sgl_count - 1) {
-                               /* unmap the last bounce that is < PAGE_SIZE */
-                               kunmap_atomic((void *)bounce_addr);
-                       }
-               }
+       vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
 
-               kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset));
+       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);
        }
 
-       local_irq_restore(flags);
+       if (ret != 0)
+               return ret;
 
-       return total_copied;
-}
+       atomic_inc(&stor_device->num_outstanding_req);
 
+       return ret;
+}
 
-/* 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)
+static int storvsc_device_alloc(struct scsi_device *sdevice)
 {
-       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);
+       struct stor_mem_pools *memp;
+       int number = STORVSC_MIN_BUF_NR;
 
-       for (i = 0; i < orig_sgl_count; i++) {
-               src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])))
-                               + orig_sgl[i].offset;
-               src = src_addr;
-               srclen = orig_sgl[i].length;
+       memp = kzalloc(sizeof(struct stor_mem_pools), GFP_KERNEL);
+       if (!memp)
+               return -ENOMEM;
 
-               if (bounce_addr == 0)
-                       bounce_addr =
-                       (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])));
+       memp->request_pool =
+               kmem_cache_create(dev_name(&sdevice->sdev_dev),
+                               sizeof(struct storvsc_cmd_request), 0,
+                               SLAB_HWCACHE_ALIGN, NULL);
 
-               while (srclen) {
-                       /* assume bounce offset always == 0 */
-                       dest = bounce_addr + bounce_sgl[j].length;
-                       destlen = PAGE_SIZE - bounce_sgl[j].length;
+       if (!memp->request_pool)
+               goto err0;
 
-                       copylen = min(srclen, destlen);
-                       memcpy((void *)dest, (void *)src, copylen);
+       memp->request_mempool = mempool_create(number, mempool_alloc_slab,
+                                               mempool_free_slab,
+                                               memp->request_pool);
 
-                       total_copied += copylen;
-                       bounce_sgl[j].length += copylen;
-                       srclen -= copylen;
-                       src += copylen;
+       if (!memp->request_mempool)
+               goto err1;
 
-                       if (bounce_sgl[j].length == PAGE_SIZE) {
-                               /* full..move to next entry */
-                               kunmap_atomic((void *)bounce_addr);
-                               j++;
+       sdevice->hostdata = memp;
 
-                               /* 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])));
+       return 0;
 
-                       } else if (srclen == 0 && i == orig_sgl_count - 1) {
-                               /* unmap the last bounce that is < PAGE_SIZE */
-                               kunmap_atomic((void *)bounce_addr);
-                       }
-               }
+err1:
+       kmem_cache_destroy(memp->request_pool);
 
-               kunmap_atomic((void *)(src_addr - orig_sgl[i].offset));
-       }
+err0:
+       kfree(memp);
+       return -ENOMEM;
+}
 
-       local_irq_restore(flags);
+static void storvsc_device_destroy(struct scsi_device *sdevice)
+{
+       struct stor_mem_pools *memp = sdevice->hostdata;
 
-       return total_copied;
+       mempool_destroy(memp->request_mempool);
+       kmem_cache_destroy(memp->request_pool);
+       kfree(memp);
+       sdevice->hostdata = NULL;
 }
 
-
-static int storvsc_remove(struct hv_device *dev)
+static int storvsc_device_configure(struct scsi_device *sdevice)
 {
-       struct storvsc_device *stor_device = hv_get_drvdata(dev);
-       struct Scsi_Host *host = stor_device->host;
-
-       scsi_remove_host(host);
+       scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
+                               STORVSC_MAX_IO_REQUESTS);
 
-       scsi_host_put(host);
+       blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
 
-       storvsc_dev_remove(dev);
+       blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
 
        return 0;
 }
 
-
 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
                           sector_t capacity, int *info)
 {
@@ -1108,10 +1171,13 @@ static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
        return 0;
 }
 
-static int storvsc_host_reset(struct hv_device *device)
+static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
 {
+       struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+       struct hv_device *device = host_dev->dev;
+
        struct storvsc_device *stor_device;
-       struct hv_storvsc_request *request;
+       struct storvsc_cmd_request *request;
        struct vstor_packet *vstor_packet;
        int ret, t;
 
@@ -1150,105 +1216,16 @@ static int storvsc_host_reset(struct hv_device *device)
        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)
+static bool storvsc_scsi_cmd_ok(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 */
+       /*
+        * smartd sends this command and the host does not handle
+        * this. So, don't send it.
+        */
        case SET_WINDOW:
                scmnd->result = ILLEGAL_REQUEST << 16;
                allowed = false;
@@ -1259,15 +1236,11 @@ static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
        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;
@@ -1276,38 +1249,31 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
        struct vmscsi_request *vm_srb;
        struct stor_mem_pools *memp = scmnd->device->hostdata;
 
-       if (storvsc_check_scsi_cmd(scmnd) == false) {
+       if (!storvsc_scsi_cmd_ok(scmnd)) {
                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);
+
+       /*
+        * We might be invoked in an interrupt context; hence
+        * mempool_alloc() can fail.
+        */
        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;
+       vm_srb = &cmd_request->vstor_packet.vm_srb;
 
 
        /* Build the SRB */
@@ -1323,8 +1289,6 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
                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;
@@ -1335,10 +1299,10 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
 
        memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
 
-       request->sense_buffer = scmnd->sense_buffer;
+       cmd_request->sense_buffer = scmnd->sense_buffer;
 
 
-       request->data_buffer.len = scsi_bufflen(scmnd);
+       cmd_request->data_buffer.len = scsi_bufflen(scmnd);
        if (scsi_sg_count(scmnd)) {
                sgl = (struct scatterlist *)scsi_sglist(scmnd);
                sg_count = scsi_sg_count(scmnd);
@@ -1350,11 +1314,8 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *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;
+                               ret = SCSI_MLQUEUE_HOST_BUSY;
+                               goto queue_error;
                        }
 
                        cmd_request->bounce_sgl_count =
@@ -1370,41 +1331,42 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
                        sg_count = cmd_request->bounce_sgl_count;
                }
 
-               request->data_buffer.offset = sgl[0].offset;
+               cmd_request->data_buffer.offset = sgl[0].offset;
 
                for (i = 0; i < sg_count; i++)
-                       request->data_buffer.pfn_array[i] =
+                       cmd_request->data_buffer.pfn_array[i] =
                                page_to_pfn(sg_page((&sgl[i])));
 
        } else if (scsi_sglist(scmnd)) {
-               request->data_buffer.offset =
+               cmd_request->data_buffer.offset =
                        virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
-               request->data_buffer.pfn_array[0] =
+               cmd_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);
+       ret = storvsc_do_io(dev, cmd_request);
 
        if (ret == -EAGAIN) {
                /* no more space */
 
-               if (cmd_request->bounce_sgl_count)
+               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;
+                       ret = SCSI_MLQUEUE_DEVICE_BUSY;
+                       goto queue_error;
+               }
        }
 
+       return 0;
+
+queue_error:
+       mempool_free(cmd_request, memp->request_mempool);
+       scmnd->host_scribble = NULL;
        return ret;
 }
 
-/* Scsi driver */
 static struct scsi_host_template scsi_driver = {
        .module =               THIS_MODULE,
        .name =                 "storvsc_host_t",
@@ -1445,11 +1407,6 @@ static const struct hv_vmbus_device_id id_table[] = {
 
 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)
 {
@@ -1457,7 +1414,6 @@ static int storvsc_probe(struct hv_device *device,
        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;
 
@@ -1490,9 +1446,6 @@ static int storvsc_probe(struct hv_device *device,
        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;
 
@@ -1512,12 +1465,14 @@ static int storvsc_probe(struct hv_device *device,
 
        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;
+       } else {
+               target = (device->dev_instance.b[5] << 8 |
+                        device->dev_instance.b[4]);
+               ret = scsi_add_device(host, 0, target, 0);
+               if (ret) {
+                       scsi_remove_host(host);
+                       goto err_out2;
+               }
        }
        return 0;
 
@@ -1539,7 +1494,17 @@ err_out0:
        return ret;
 }
 
-/* The one and only one */
+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);
+       storvsc_dev_remove(dev);
+       scsi_host_put(host);
+
+       return 0;
+}
 
 static struct hv_driver storvsc_drv = {
        .name = KBUILD_MODNAME,