linux_dsm_epyc7002/include/scsi/scsi_transport.h
Christoph Hellwig e02f3f5922 [SCSI] remove target parent limitiation
When James Smart fixed the issue of the userspace scan atributes
crashing the system with the FC transport class he added a patch to
let the transport class check if the parent is valid for a given
transport class.

When adding support for the integrated raid of fusion sas devices
we ran into a problem with that, as it didn't allow adding virtual
raid volumes without the transport class knowing about it.

So this patch adds a user_scan attribute instead, that takes over from
scsi_scan_host_selected if the transport class sets it and thus lets
the transport class control the user-initiated scanning.  As this
plugs the hole about user-initiated scanning the target_parent hook
goes away and we rely on callers of the scanning routines to do
something sensible.

For SAS this meant I had to switch from a spinlock to a mutex to
synchronize the topology linked lists, in FC they were completely
unsynchronized which seems wrong.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14 10:55:05 -06:00

92 lines
2.9 KiB
C

/*
* Transport specific attributes.
*
* Copyright (c) 2003 Silicon Graphics, Inc. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef SCSI_TRANSPORT_H
#define SCSI_TRANSPORT_H
#include <linux/transport_class.h>
#include <scsi/scsi_host.h>
struct scsi_transport_template {
/* the attribute containers */
struct transport_container host_attrs;
struct transport_container target_attrs;
struct transport_container device_attrs;
/*
* If set, called from sysfs and legacy procfs rescanning code.
*/
int (*user_scan)(struct Scsi_Host *, uint, uint, uint);
/* The size of the specific transport attribute structure (a
* space of this size will be left at the end of the
* scsi_* structure */
int device_size;
int device_private_offset;
int target_size;
int target_private_offset;
int host_size;
/* no private offset for the host; there's an alternative mechanism */
/*
* True if the transport wants to use a host-based work-queue
*/
unsigned int create_work_queue : 1;
};
#define transport_class_to_shost(tc) \
dev_to_shost((tc)->dev)
/* Private area maintenance. The driver requested allocations come
* directly after the transport class allocations (if any). The idea
* is that you *must* call these only once. The code assumes that the
* initial values are the ones the transport specific code requires */
static inline void
scsi_transport_reserve_target(struct scsi_transport_template * t, int space)
{
BUG_ON(t->target_private_offset != 0);
t->target_private_offset = ALIGN(t->target_size, sizeof(void *));
t->target_size = t->target_private_offset + space;
}
static inline void
scsi_transport_reserve_device(struct scsi_transport_template * t, int space)
{
BUG_ON(t->device_private_offset != 0);
t->device_private_offset = ALIGN(t->device_size, sizeof(void *));
t->device_size = t->device_private_offset + space;
}
static inline void *
scsi_transport_target_data(struct scsi_target *starget)
{
struct Scsi_Host *shost = dev_to_shost(&starget->dev);
return (u8 *)starget->starget_data
+ shost->transportt->target_private_offset;
}
static inline void *
scsi_transport_device_data(struct scsi_device *sdev)
{
struct Scsi_Host *shost = sdev->host;
return (u8 *)sdev->sdev_data
+ shost->transportt->device_private_offset;
}
#endif /* SCSI_TRANSPORT_H */