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 <linux/bug.h> 26 #include <scsi/scsi_host.h> 27 #include <scsi/scsi_device.h> 28 29 struct scsi_transport_template { 30 /* the attribute containers */ 31 struct transport_container host_attrs; 32 struct transport_container target_attrs; 33 struct transport_container device_attrs; 34 35 /* 36 * If set, called from sysfs and legacy procfs rescanning code. 37 */ 38 int (*user_scan)(struct Scsi_Host *, uint, uint, u64); 39 40 /* The size of the specific transport attribute structure (a 41 * space of this size will be left at the end of the 42 * scsi_* structure */ 43 int device_size; 44 int device_private_offset; 45 int target_size; 46 int target_private_offset; 47 int host_size; 48 /* no private offset for the host; there's an alternative mechanism */ 49 50 /* 51 * True if the transport wants to use a host-based work-queue 52 */ 53 unsigned int create_work_queue : 1; 54 55 /* 56 * Allows a transport to override the default error handler. 57 */ 58 void (* eh_strategy_handler)(struct Scsi_Host *); 59 60 /* 61 * This is an optional routine that allows the transport to become 62 * involved when a scsi io timer fires. The return value tells the 63 * timer routine how to finish the io timeout handling: 64 * EH_HANDLED: I fixed the error, please complete the command 65 * EH_RESET_TIMER: I need more time, reset the timer and 66 * begin counting again 67 * EH_NOT_HANDLED Begin normal error recovery 68 */ 69 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 70 71 /* 72 * Used as callback for the completion of i_t_nexus request 73 * for target drivers. 74 */ 75 int (* it_nexus_response)(struct Scsi_Host *, u64, int); 76 77 /* 78 * Used as callback for the completion of task management 79 * request for target drivers. 80 */ 81 int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int); 82 }; 83 84 #define transport_class_to_shost(tc) \ 85 dev_to_shost((tc)->parent) 86 87 88 /* Private area maintenance. The driver requested allocations come 89 * directly after the transport class allocations (if any). The idea 90 * is that you *must* call these only once. The code assumes that the 91 * initial values are the ones the transport specific code requires */ 92 static inline void 93 scsi_transport_reserve_target(struct scsi_transport_template * t, int space) 94 { 95 BUG_ON(t->target_private_offset != 0); 96 t->target_private_offset = ALIGN(t->target_size, sizeof(void *)); 97 t->target_size = t->target_private_offset + space; 98 } 99 static inline void 100 scsi_transport_reserve_device(struct scsi_transport_template * t, int space) 101 { 102 BUG_ON(t->device_private_offset != 0); 103 t->device_private_offset = ALIGN(t->device_size, sizeof(void *)); 104 t->device_size = t->device_private_offset + space; 105 } 106 static inline void * 107 scsi_transport_target_data(struct scsi_target *starget) 108 { 109 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 110 return (u8 *)starget->starget_data 111 + shost->transportt->target_private_offset; 112 113 } 114 static inline void * 115 scsi_transport_device_data(struct scsi_device *sdev) 116 { 117 struct Scsi_Host *shost = sdev->host; 118 return (u8 *)sdev->sdev_data 119 + shost->transportt->device_private_offset; 120 } 121 122 #endif /* SCSI_TRANSPORT_H */ 123