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 23#include <linux/transport_class.h> 24#include <linux/blkdev.h> 25#include <scsi/scsi_host.h> 26#include <scsi/scsi_device.h> 27 28struct scsi_transport_template { 29 /* the attribute containers */ 30 struct transport_container host_attrs; 31 struct transport_container target_attrs; 32 struct transport_container device_attrs; 33 34 /* 35 * If set, called from sysfs and legacy procfs rescanning code. 36 */ 37 int (*user_scan)(struct Scsi_Host *, uint, uint, uint); 38 39 /* The size of the specific transport attribute structure (a 40 * space of this size will be left at the end of the 41 * scsi_* structure */ 42 int device_size; 43 int device_private_offset; 44 int target_size; 45 int target_private_offset; 46 int host_size; 47 /* no private offset for the host; there's an alternative mechanism */ 48 49 /* 50 * True if the transport wants to use a host-based work-queue 51 */ 52 unsigned int create_work_queue : 1; 53 54 /* 55 * Allows a transport to override the default error handler. 56 */ 57 void (* eh_strategy_handler)(struct Scsi_Host *); 58 59 /* 60 * This is an optional routine that allows the transport to become 61 * involved when a scsi io timer fires. The return value tells the 62 * timer routine how to finish the io timeout handling: 63 * EH_HANDLED: I fixed the error, please complete the command 64 * EH_RESET_TIMER: I need more time, reset the timer and 65 * begin counting again 66 * EH_NOT_HANDLED Begin normal error recovery 67 */ 68 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 69 70 /* 71 * Used as callback for the completion of i_t_nexus request 72 * for target drivers. 73 */ 74 int (* it_nexus_response)(struct Scsi_Host *, u64, int); 75 76 /* 77 * Used as callback for the completion of task management 78 * request for target drivers. 79 */ 80 int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int); 81}; 82 83#define transport_class_to_shost(tc) \ 84 dev_to_shost((tc)->parent) 85 86 87/* Private area maintenance. The driver requested allocations come 88 * directly after the transport class allocations (if any). The idea 89 * is that you *must* call these only once. The code assumes that the 90 * initial values are the ones the transport specific code requires */ 91static inline void 92scsi_transport_reserve_target(struct scsi_transport_template * t, int space) 93{ 94 BUG_ON(t->target_private_offset != 0); 95 t->target_private_offset = ALIGN(t->target_size, sizeof(void *)); 96 t->target_size = t->target_private_offset + space; 97} 98static inline void 99scsi_transport_reserve_device(struct scsi_transport_template * t, int space) 100{ 101 BUG_ON(t->device_private_offset != 0); 102 t->device_private_offset = ALIGN(t->device_size, sizeof(void *)); 103 t->device_size = t->device_private_offset + space; 104} 105static inline void * 106scsi_transport_target_data(struct scsi_target *starget) 107{ 108 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 109 return (u8 *)starget->starget_data 110 + shost->transportt->target_private_offset; 111 112} 113static inline void * 114scsi_transport_device_data(struct scsi_device *sdev) 115{ 116 struct Scsi_Host *shost = sdev->host; 117 return (u8 *)sdev->sdev_data 118 + shost->transportt->device_private_offset; 119} 120 121#endif /* SCSI_TRANSPORT_H */ 122