scsi_transport.h 3.9 KB

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  1. /*
  2. * Transport specific attributes.
  3. *
  4. * Copyright (c) 2003 Silicon Graphics, Inc. All rights reserved.
  5. *
  6. * This program is free software; you can redistribute it and/or modify
  7. * it under the terms of the GNU General Public License as published by
  8. * the Free Software Foundation; either version 2 of the License, or
  9. * (at your option) any later version.
  10. *
  11. * This program is distributed in the hope that it will be useful,
  12. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14. * GNU General Public License for more details.
  15. *
  16. * You should have received a copy of the GNU General Public License
  17. * along with this program; if not, write to the Free Software
  18. * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19. */
  20. #ifndef SCSI_TRANSPORT_H
  21. #define SCSI_TRANSPORT_H
  22. #include <linux/transport_class.h>
  23. #include <linux/blkdev.h>
  24. #include <scsi/scsi_host.h>
  25. #include <scsi/scsi_device.h>
  26. struct scsi_transport_template {
  27. /* the attribute containers */
  28. struct transport_container host_attrs;
  29. struct transport_container target_attrs;
  30. struct transport_container device_attrs;
  31. /*
  32. * If set, called from sysfs and legacy procfs rescanning code.
  33. */
  34. int (*user_scan)(struct Scsi_Host *, uint, uint, uint);
  35. /* The size of the specific transport attribute structure (a
  36. * space of this size will be left at the end of the
  37. * scsi_* structure */
  38. int device_size;
  39. int device_private_offset;
  40. int target_size;
  41. int target_private_offset;
  42. int host_size;
  43. /* no private offset for the host; there's an alternative mechanism */
  44. /*
  45. * True if the transport wants to use a host-based work-queue
  46. */
  47. unsigned int create_work_queue : 1;
  48. /*
  49. * Allows a transport to override the default error handler.
  50. */
  51. void (* eh_strategy_handler)(struct Scsi_Host *);
  52. /*
  53. * This is an optional routine that allows the transport to become
  54. * involved when a scsi io timer fires. The return value tells the
  55. * timer routine how to finish the io timeout handling:
  56. * EH_HANDLED: I fixed the error, please complete the command
  57. * EH_RESET_TIMER: I need more time, reset the timer and
  58. * begin counting again
  59. * EH_NOT_HANDLED Begin normal error recovery
  60. */
  61. enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
  62. /*
  63. * Used as callback for the completion of i_t_nexus request
  64. * for target drivers.
  65. */
  66. int (* it_nexus_response)(struct Scsi_Host *, u64, int);
  67. /*
  68. * Used as callback for the completion of task management
  69. * request for target drivers.
  70. */
  71. int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int);
  72. };
  73. #define transport_class_to_shost(tc) \
  74. dev_to_shost((tc)->parent)
  75. /* Private area maintenance. The driver requested allocations come
  76. * directly after the transport class allocations (if any). The idea
  77. * is that you *must* call these only once. The code assumes that the
  78. * initial values are the ones the transport specific code requires */
  79. static inline void
  80. scsi_transport_reserve_target(struct scsi_transport_template * t, int space)
  81. {
  82. BUG_ON(t->target_private_offset != 0);
  83. t->target_private_offset = ALIGN(t->target_size, sizeof(void *));
  84. t->target_size = t->target_private_offset + space;
  85. }
  86. static inline void
  87. scsi_transport_reserve_device(struct scsi_transport_template * t, int space)
  88. {
  89. BUG_ON(t->device_private_offset != 0);
  90. t->device_private_offset = ALIGN(t->device_size, sizeof(void *));
  91. t->device_size = t->device_private_offset + space;
  92. }
  93. static inline void *
  94. scsi_transport_target_data(struct scsi_target *starget)
  95. {
  96. struct Scsi_Host *shost = dev_to_shost(&starget->dev);
  97. return (u8 *)starget->starget_data
  98. + shost->transportt->target_private_offset;
  99. }
  100. static inline void *
  101. scsi_transport_device_data(struct scsi_device *sdev)
  102. {
  103. struct Scsi_Host *shost = sdev->host;
  104. return (u8 *)sdev->sdev_data
  105. + shost->transportt->device_private_offset;
  106. }
  107. #endif /* SCSI_TRANSPORT_H */