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