1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Transport specific attributes. 4 * 5 * Copyright (c) 2003 Silicon Graphics, Inc. All rights reserved. 6 */ 7 #ifndef SCSI_TRANSPORT_H 8 #define SCSI_TRANSPORT_H 9 10 #include <linux/transport_class.h> 11 #include <linux/blkdev.h> 12 #include <linux/bug.h> 13 #include <scsi/scsi_host.h> 14 #include <scsi/scsi_device.h> 15 16 struct scsi_transport_template { 17 /* the attribute containers */ 18 struct transport_container host_attrs; 19 struct transport_container target_attrs; 20 struct transport_container device_attrs; 21 22 /* 23 * If set, called from sysfs and legacy procfs rescanning code. 24 */ 25 int (*user_scan)(struct Scsi_Host *, uint, uint, u64); 26 27 /* The size of the specific transport attribute structure (a 28 * space of this size will be left at the end of the 29 * scsi_* structure */ 30 int device_size; 31 int device_private_offset; 32 int target_size; 33 int target_private_offset; 34 int host_size; 35 /* no private offset for the host; there's an alternative mechanism */ 36 37 /* 38 * True if the transport wants to use a host-based work-queue 39 */ 40 unsigned int create_work_queue : 1; 41 42 /* 43 * Allows a transport to override the default error handler. 44 */ 45 void (* eh_strategy_handler)(struct Scsi_Host *); 46 }; 47 48 #define transport_class_to_shost(tc) \ 49 dev_to_shost((tc)->parent) 50 51 52 /* Private area maintenance. The driver requested allocations come 53 * directly after the transport class allocations (if any). The idea 54 * is that you *must* call these only once. The code assumes that the 55 * initial values are the ones the transport specific code requires */ 56 static inline void 57 scsi_transport_reserve_target(struct scsi_transport_template * t, int space) 58 { 59 BUG_ON(t->target_private_offset != 0); 60 t->target_private_offset = ALIGN(t->target_size, sizeof(void *)); 61 t->target_size = t->target_private_offset + space; 62 } 63 static inline void 64 scsi_transport_reserve_device(struct scsi_transport_template * t, int space) 65 { 66 BUG_ON(t->device_private_offset != 0); 67 t->device_private_offset = ALIGN(t->device_size, sizeof(void *)); 68 t->device_size = t->device_private_offset + space; 69 } 70 static inline void * 71 scsi_transport_target_data(struct scsi_target *starget) 72 { 73 struct Scsi_Host *shost = dev_to_shost(&starget->dev); 74 return (u8 *)starget->starget_data 75 + shost->transportt->target_private_offset; 76 77 } 78 static inline void * 79 scsi_transport_device_data(struct scsi_device *sdev) 80 { 81 struct Scsi_Host *shost = sdev->host; 82 return (u8 *)sdev->sdev_data 83 + shost->transportt->device_private_offset; 84 } 85 86 void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q); 87 88 #endif /* SCSI_TRANSPORT_H */ 89