releases/3.16.3/drivers-scsi-storvsc-change-the-limits-to-reflect-the-values-on-the-host.patch

   1 From 4cd83ecdac20d30725b4f96e5d7814a1e290bc7e Mon Sep 17 00:00:00 2001
   2 From: "K. Y. Srinivasan" <kys@microsoft.com>
   3 Date: Sat, 12 Jul 2014 09:48:26 -0700
   4 Subject: Drivers: scsi: storvsc: Change the limits to reflect the values on the host
   5
   6 From: "K. Y. Srinivasan" <kys@microsoft.com>
   7
   8 commit 4cd83ecdac20d30725b4f96e5d7814a1e290bc7e upstream.
   9
  10 Hyper-V hosts can support multiple targets and multiple channels and larger number of
  11 LUNs per target. Update the code to reflect this. With this patch we can correctly
  12 enumerate all the paths in a multi-path storage environment.
  13
  14 Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
  15 Reviewed-by: Hannes Reinecke <hare@suse.de>
  16 Signed-off-by: Christoph Hellwig <hch@lst.de>
  17 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  18
  19 ---
  20  drivers/scsi/storvsc_drv.c |   51 +++++++++++++++++++++++++++++----------------
  21  1 file changed, 33 insertions(+), 18 deletions(-)
  22
  23 --- a/drivers/scsi/storvsc_drv.c
  24 +++ b/drivers/scsi/storvsc_drv.c
  25 @@ -331,17 +331,17 @@ static int storvsc_timeout = 180;
  26
  27  static void storvsc_on_channel_callback(void *context);
  28
  29 -/*
  30 - * In Hyper-V, each port/path/target maps to 1 scsi host adapter.  In
  31 - * reality, the path/target is not used (ie always set to 0) so our
  32 - * scsi host adapter essentially has 1 bus with 1 target that contains
  33 - * up to 256 luns.
  34 - */
  35 -#define STORVSC_MAX_LUNS_PER_TARGET                    64
  36 -#define STORVSC_MAX_TARGETS                            1
  37 -#define STORVSC_MAX_CHANNELS                           1
  38 -
  39 -
  40 +#define STORVSC_MAX_LUNS_PER_TARGET                    255
  41 +#define STORVSC_MAX_TARGETS                            2
  42 +#define STORVSC_MAX_CHANNELS                           8
  43 +
  44 +#define STORVSC_FC_MAX_LUNS_PER_TARGET                 255
  45 +#define STORVSC_FC_MAX_TARGETS                         128
  46 +#define STORVSC_FC_MAX_CHANNELS                                8
  47 +
  48 +#define STORVSC_IDE_MAX_LUNS_PER_TARGET                        64
  49 +#define STORVSC_IDE_MAX_TARGETS                                1
  50 +#define STORVSC_IDE_MAX_CHANNELS                       1
  51
  52  struct storvsc_cmd_request {
  53         struct list_head entry;
  54 @@ -1713,7 +1713,6 @@ static struct scsi_host_template scsi_dr
  55         .slave_destroy =        storvsc_device_destroy,
  56         .slave_configure =      storvsc_device_configure,
  57         .cmd_per_lun =          1,
  58 -       /* 64 max_queue * 1 target */
  59         .can_queue =            STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS,
  60         .this_id =              -1,
  61         /* no use setting to 0 since ll_blk_rw reset it to 1 */
  62 @@ -1778,6 +1777,9 @@ static int storvsc_probe(struct hv_devic
  63         }
  64
  65
  66 +       if (dev_id->driver_data == SFC_GUID)
  67 +               scsi_driver.can_queue = (STORVSC_MAX_IO_REQUESTS *
  68 +                                        STORVSC_FC_MAX_TARGETS);
  69         host = scsi_host_alloc(&scsi_driver,
  70                                sizeof(struct hv_host_device));
  71         if (!host)
  72 @@ -1811,12 +1813,25 @@ static int storvsc_probe(struct hv_devic
  73         host_dev->path = stor_device->path_id;
  74         host_dev->target = stor_device->target_id;
  75
  76 -       /* max # of devices per target */
  77 -       host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
  78 -       /* max # of targets per channel */
  79 -       host->max_id = STORVSC_MAX_TARGETS;
  80 -       /* max # of channels */
  81 -       host->max_channel = STORVSC_MAX_CHANNELS - 1;
  82 +       switch (dev_id->driver_data) {
  83 +       case SFC_GUID:
  84 +               host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
  85 +               host->max_id = STORVSC_FC_MAX_TARGETS;
  86 +               host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
  87 +               break;
  88 +
  89 +       case SCSI_GUID:
  90 +               host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
  91 +               host->max_id = STORVSC_MAX_TARGETS;
  92 +               host->max_channel = STORVSC_MAX_CHANNELS - 1;
  93 +               break;
  94 +
  95 +       default:
  96 +               host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
  97 +               host->max_id = STORVSC_IDE_MAX_TARGETS;
  98 +               host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
  99 +               break;
 100 +       }
 101         /* max cmd length */
 102         host->max_cmd_len = STORVSC_MAX_CMD_LEN;
 103