freebsd-dev/sys/cam/ctl/ctl_frontend.h
Kenneth D. Merry 130f4520cb Add the CAM Target Layer (CTL).
CTL is a disk and processor device emulation subsystem originally written
for Copan Systems under Linux starting in 2003.  It has been shipping in
Copan (now SGI) products since 2005.

It was ported to FreeBSD in 2008, and thanks to an agreement between SGI
(who acquired Copan's assets in 2010) and Spectra Logic in 2010, CTL is
available under a BSD-style license.  The intent behind the agreement was
that Spectra would work to get CTL into the FreeBSD tree.

Some CTL features:

 - Disk and processor device emulation.
 - Tagged queueing
 - SCSI task attribute support (ordered, head of queue, simple tags)
 - SCSI implicit command ordering support.  (e.g. if a read follows a mode
   select, the read will be blocked until the mode select completes.)
 - Full task management support (abort, LUN reset, target reset, etc.)
 - Support for multiple ports
 - Support for multiple simultaneous initiators
 - Support for multiple simultaneous backing stores
 - Persistent reservation support
 - Mode sense/select support
 - Error injection support
 - High Availability support (1)
 - All I/O handled in-kernel, no userland context switch overhead.

(1) HA Support is just an API stub, and needs much more to be fully
    functional.

ctl.c:			The core of CTL.  Command handlers and processing,
			character driver, and HA support are here.

ctl.h:			Basic function declarations and data structures.

ctl_backend.c,
ctl_backend.h:		The basic CTL backend API.

ctl_backend_block.c,
ctl_backend_block.h:	The block and file backend.  This allows for using
			a disk or a file as the backing store for a LUN.
			Multiple threads are started to do I/O to the
			backing device, primarily because the VFS API
			requires that to get any concurrency.

ctl_backend_ramdisk.c:	A "fake" ramdisk backend.  It only allocates a
			small amount of memory to act as a source and sink
			for reads and writes from an initiator.  Therefore
			it cannot be used for any real data, but it can be
			used to test for throughput.  It can also be used
			to test initiators' support for extremely large LUNs.

ctl_cmd_table.c:	This is a table with all 256 possible SCSI opcodes,
			and command handler functions defined for supported
			opcodes.

ctl_debug.h:		Debugging support.

ctl_error.c,
ctl_error.h:		CTL-specific wrappers around the CAM sense building
			functions.

ctl_frontend.c,
ctl_frontend.h:		These files define the basic CTL frontend port API.

ctl_frontend_cam_sim.c:	This is a CTL frontend port that is also a CAM SIM.
			This frontend allows for using CTL without any
			target-capable hardware.  So any LUNs you create in
			CTL are visible in CAM via this port.

ctl_frontend_internal.c,
ctl_frontend_internal.h:
			This is a frontend port written for Copan to do
			some system-specific tasks that required sending
			commands into CTL from inside the kernel.  This
			isn't entirely relevant to FreeBSD in general,
			but can perhaps be repurposed.

ctl_ha.h:		This is a stubbed-out High Availability API.  Much
			more is needed for full HA support.  See the
			comments in the header and the description of what
			is needed in the README.ctl.txt file for more
			details.

ctl_io.h:		This defines most of the core CTL I/O structures.
			union ctl_io is conceptually very similar to CAM's
			union ccb.

ctl_ioctl.h:		This defines all ioctls available through the CTL
			character device, and the data structures needed
			for those ioctls.

ctl_mem_pool.c,
ctl_mem_pool.h:		Generic memory pool implementation used by the
			internal frontend.

ctl_private.h:		Private data structres (e.g. CTL softc) and
			function prototypes.  This also includes the SCSI
			vendor and product names used by CTL.

ctl_scsi_all.c,
ctl_scsi_all.h:		CTL wrappers around CAM sense printing functions.

ctl_ser_table.c:	Command serialization table.  This defines what
			happens when one type of command is followed by
			another type of command.

ctl_util.c,
ctl_util.h:		CTL utility functions, primarily designed to be
			used from userland.  See ctladm for the primary
			consumer of these functions.  These include CDB
			building functions.

scsi_ctl.c:		CAM target peripheral driver and CTL frontend port.
			This is the path into CTL for commands from
			target-capable hardware/SIMs.

README.ctl.txt:		CTL code features, roadmap, to-do list.

usr.sbin/Makefile:	Add ctladm.

ctladm/Makefile,
ctladm/ctladm.8,
ctladm/ctladm.c,
ctladm/ctladm.h,
ctladm/util.c:		ctladm(8) is the CTL management utility.
			It fills a role similar to camcontrol(8).
			It allow configuring LUNs, issuing commands,
			injecting errors and various other control
			functions.

usr.bin/Makefile:	Add ctlstat.

ctlstat/Makefile
ctlstat/ctlstat.8,
ctlstat/ctlstat.c:	ctlstat(8) fills a role similar to iostat(8).
			It reports I/O statistics for CTL.

sys/conf/files:		Add CTL files.

sys/conf/NOTES:		Add device ctl.

sys/cam/scsi_all.h:	To conform to more recent specs, the inquiry CDB
			length field is now 2 bytes long.

			Add several mode page definitions for CTL.

sys/cam/scsi_all.c:	Handle the new 2 byte inquiry length.

sys/dev/ciss/ciss.c,
sys/dev/ata/atapi-cam.c,
sys/cam/scsi/scsi_targ_bh.c,
scsi_target/scsi_cmds.c,
mlxcontrol/interface.c:	Update for 2 byte inquiry length field.

scsi_da.h:		Add versions of the format and rigid disk pages
			that are in a more reasonable format for CTL.

amd64/conf/GENERIC,
i386/conf/GENERIC,
ia64/conf/GENERIC,
sparc64/conf/GENERIC:	Add device ctl.

i386/conf/PAE:		The CTL frontend SIM at least does not compile
			cleanly on PAE.

Sponsored by:	Copan Systems, SGI and Spectra Logic
MFC after:	1 month
2012-01-12 00:34:33 +00:00

296 lines
12 KiB
C

/*-
* Copyright (c) 2003 Silicon Graphics International Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_frontend.h#2 $
* $FreeBSD$
*/
/*
* CAM Target Layer front end registration hooks
*
* Author: Ken Merry <ken@FreeBSD.org>
*/
#ifndef _CTL_FRONTEND_H_
#define _CTL_FRONTEND_H_
typedef enum {
CTL_PORT_STATUS_NONE = 0x00,
CTL_PORT_STATUS_ONLINE = 0x01,
CTL_PORT_STATUS_TARG_ONLINE = 0x02,
CTL_PORT_STATUS_LUN_ONLINE = 0x04
} ctl_port_status;
typedef void (*port_func_t)(void *onoff_arg);
typedef int (*targ_func_t)(void *arg, struct ctl_id targ_id);
typedef int (*lun_func_t)(void *arg, struct ctl_id targ_id, int lun_id);
/*
* The ctl_frontend structure is the registration mechanism between a FETD
* (Front End Target Driver) and the CTL layer. Here is a description of
* the fields:
*
* port_type: This field tells CTL what kind of front end it is
* dealing with. This field serves two purposes.
* The first is to let CTL know whether the frontend
* in question is inside the main CTL module (i.e.
* the ioctl front end), and therefore its module
* reference count shouldn't be incremented. The
* CTL ioctl front end should continue to use the
* CTL_PORT_IOCTL argument as long as it is part of
* the main CTL module. The second is to let CTL
* know what kind of front end it is dealing with, so
* it can return the proper inquiry data for that
* particular port.
*
* num_requested_ctl_io: This is the number of ctl_io structures that the
* front end needs for its pool. This should
* generally be the maximum number of outstanding
* transactions that the FETD can handle. The CTL
* layer will add a few to this to account for
* ctl_io buffers queued for pending sense data.
* (Pending sense only gets queued if the FETD
* doesn't support autosense. e.g. non-packetized
* parallel SCSI doesn't support autosense.)
*
* port_name: A string describing the FETD. e.g. "LSI 1030T U320"
* or whatever you want to use to describe the driver.
*
*
* physical_port: This is the physical port number of this
* particular port within the driver/hardware. This
* number is hardware/driver specific.
* virtual_port: This is the virtual port number of this
* particular port. This is for things like NP-IV.
*
* port_online(): This function is called, with onoff_arg as its
* argument, by the CTL layer when it wants the FETD
* to start responding to selections on the specified
* target ID. (targ_target)
*
* port_offline(): This function is called, with onoff_arg as its
* argument, by the CTL layer when it wants the FETD
* to stop responding to selection on the specified
* target ID. (targ_target)
*
* onoff_arg: This is supplied as an argument to port_online()
* and port_offline(). This is specified by the
* FETD.
*
* targ_enable(): This function is called, with targ_lun_arg and a
* target ID as its arguments, by CTL when it wants
* the FETD to enable a particular target. targ_enable()
* will always be called for a particular target ID
* before any LUN is enabled for that target. If the
* FETD does not support enabling targets, but rather
* LUNs, it should ignore this call and return 0. If
* the FETD does support enabling targets, it should
* return 0 for success and non-zero if it cannot
* enable the given target.
*
* TODO: Add the ability to specify a WWID here.
*
* targ_disable(): This function is called, with targ_lun_arg and a
* target ID as its arguments, by CTL when it wants
* the FETD to disable a particular target.
* targ_disable() will always be called for a
* particular target ID after all LUNs are disabled
* on that particular target. If the FETD does not
* support enabling targets, it should ignore this
* call and return 0. If the FETD does support
* enabling targets, it should return 0 for success,
* and non-zero if it cannot disable the given target.
*
* lun_enable(): This function is called, with targ_lun_arg, a target
* ID and a LUN ID as its arguments, by CTL when it
* wants the FETD to enable a particular LUN. If the
* FETD doesn't really know about LUNs, it should
* just ignore this call and return 0. If the FETD
* cannot enable the requested LUN for some reason, the
* FETD should return non-zero status.
*
* lun_disable(): This function is called, with targ_lun_arg, a target
* ID and LUN ID as its arguments, by CTL when it
* wants the FETD to disable a particular LUN. If the
* FETD doesn't really know about LUNs, it should just
* ignore this call and return 0. If the FETD cannot
* disable the requested LUN for some reason, the
* FETD should return non-zero status.
*
* targ_lun_arg: This is supplied as an argument to the targ/lun
* enable/disable() functions. This is specified by
* the FETD.
*
* fe_datamove(): This function is called one or more times per I/O
* by the CTL layer to tell the FETD to initiate a
* DMA to or from the data buffer(s) specified by
* the passed-in ctl_io structure.
*
* fe_done(): This function is called by the CTL layer when a
* particular SCSI I/O or task management command has
* completed. For SCSI I/O requests (CTL_IO_SCSI),
* sense data is always supplied if the status is
* CTL_SCSI_ERROR and the SCSI status byte is
* SCSI_STATUS_CHECK_COND. If the FETD doesn't
* support autosense, the sense should be queued
* back to the CTL layer via ctl_queue_sense().
*
* fe_dump(): This function, if it exists, is called by CTL
* to request a dump of any debugging information or
* state to the console.
*
* max_targets: The maximum number of targets that we can create
* per-port.
*
* max_target_id: The highest target ID that we can use.
*
* targ_port: The CTL layer assigns a "port number" to every
* FETD. This port number should be passed back in
* in the header of every ctl_io that is queued to
* the CTL layer. This enables us to determine
* which bus the command came in on.
*
* ctl_pool_ref: Memory pool reference used by the FETD in calls to
* ctl_alloc_io().
*
* max_initiators: Maximum number of initiators that the FETD is
* allowed to have. Initiators should be numbered
* from 0 to max_initiators - 1. This value will
* typically be 16, and thus not a problem for
* parallel SCSI. This may present issues for Fibre
* Channel.
*
* wwnn World Wide Node Name to be used by the FETD.
* Note that this is set *after* registration. It
* will be set prior to the online function getting
* called.
*
* wwpn World Wide Port Name to be used by the FETD.
* Note that this is set *after* registration. It
* will be set prior to the online function getting
* called.
*
* status: Used by CTL to keep track of per-FETD state.
*
* links: Linked list pointers, used by CTL. The FETD
* shouldn't touch this field.
*/
struct ctl_frontend {
ctl_port_type port_type; /* passed to CTL */
int num_requested_ctl_io; /* passed to CTL */
char *port_name; /* passed to CTL */
int physical_port; /* passed to CTL */
int virtual_port; /* passed to CTL */
port_func_t port_online; /* passed to CTL */
port_func_t port_offline; /* passed to CTL */
void *onoff_arg; /* passed to CTL */
targ_func_t targ_enable; /* passed to CTL */
targ_func_t targ_disable; /* passed to CTL */
lun_func_t lun_enable; /* passed to CTL */
lun_func_t lun_disable; /* passed to CTL */
void *targ_lun_arg; /* passed to CTL */
void (*fe_datamove)(union ctl_io *io); /* passed to CTL */
void (*fe_done)(union ctl_io *io); /* passed to CTL */
void (*fe_dump)(void); /* passed to CTL */
int max_targets; /* passed to CTL */
int max_target_id; /* passed to CTL */
int32_t targ_port; /* passed back to FETD */
void *ctl_pool_ref; /* passed back to FETD */
uint32_t max_initiators; /* passed back to FETD */
uint64_t wwnn; /* set by CTL before online */
uint64_t wwpn; /* set by CTL before online */
ctl_port_status status; /* used by CTL */
STAILQ_ENTRY(ctl_frontend) links; /* used by CTL */
};
/*
* This may block until resources are allocated. Called at FETD module load
* time. Returns 0 for success, non-zero for failure.
*/
int ctl_frontend_register(struct ctl_frontend *fe, int master_SC);
/*
* Called at FETD module unload time.
* Returns 0 for success, non-zero for failure.
*/
int ctl_frontend_deregister(struct ctl_frontend *fe);
/*
* Called to set the WWNN and WWPN for a particular frontend.
*/
void ctl_frontend_set_wwns(struct ctl_frontend *fe, int wwnn_valid,
uint64_t wwnn, int wwpn_valid, uint64_t wwpn);
/*
* Called to bring a particular frontend online.
*/
void ctl_frontend_online(struct ctl_frontend *fe);
/*
* Called to take a particular frontend offline.
*/
void ctl_frontend_offline(struct ctl_frontend *fe);
/*
* This routine queues I/O and task management requests from the FETD to the
* CTL layer. Returns immediately. Returns 0 for success, non-zero for
* failure.
*/
int ctl_queue(union ctl_io *io);
/*
* This routine is used if the front end interface doesn't support
* autosense (e.g. non-packetized parallel SCSI). This will queue the
* scsiio structure back to a per-lun pending sense queue. This MUST be
* called BEFORE any request sense can get queued to the CTL layer -- I
* need it in the queue in order to service the request. The scsiio
* structure passed in here will be freed by the CTL layer when sense is
* retrieved by the initiator. Returns 0 for success, non-zero for failure.
*/
int ctl_queue_sense(union ctl_io *io);
/*
* This routine adds an initiator to CTL's port database. The WWPN should
* be the FC WWPN, if available. The targ_port field should be the same as
* the targ_port passed back from CTL in the ctl_frontend structure above.
* The iid field should be the same as the iid passed in the nexus of each
* ctl_io from this initiator.
*/
int ctl_add_initiator(uint64_t wwpn, int32_t targ_port, uint32_t iid);
/*
* This routine will remove an initiator from CTL's port database. The
* targ_port field should be the same as the targ_port passed back in the
* ctl_frontend structure above. The iid field should be the same as the
* iid passed in the nexus of each ctl_io from this initiator.
*/
int
ctl_remove_initiator(int32_t targ_port, uint32_t iid);
#endif /* _CTL_FRONTEND_H_ */