freebsd-dev/sys/cam/ctl/ctl_mem_pool.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

84 lines
2.7 KiB
C

/*-
* Copyright (c) 2003, 2004 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_mem_pool.h#1 $
* $FreeBSD$
*/
/*
* CAM Target Layer memory pool code.
*
* Author: Ken Merry <ken@FreeBSD.org>
*/
#ifndef _CTL_MEMPOOL_H_
#define _CTL_MEMPOOL_H_
typedef enum {
CTL_MEM_POOL_NONE,
CTL_MEM_POOL_PERM_GROW
} ctl_mem_pool_flags;
struct ctl_mem_pool {
ctl_mem_pool_flags flags;
int chunk_size;
int grow_inc;
struct mtx lock;
struct cv wait_mem;
STAILQ_HEAD(, ctl_mem_element) free_mem_list;
};
typedef enum {
CTL_MEM_ELEMENT_NONE,
CTL_MEM_ELEMENT_PREALLOC
} ctl_mem_element_flags;
struct ctl_mem_element {
ctl_mem_element_flags flags;
struct ctl_mem_pool *pool;
uint8_t *bytes;
STAILQ_ENTRY(ctl_mem_element) links;
};
#ifdef _KERNEL
MALLOC_DECLARE(M_CTL_POOL);
int ctl_init_mem_pool(struct ctl_mem_pool *pool, int chunk_size,
ctl_mem_pool_flags flags, int grow_inc,
int initial_pool_size);
struct ctl_mem_element *ctl_alloc_mem_element(struct ctl_mem_pool *pool,
int can_wait);
void ctl_free_mem_element(struct ctl_mem_element *mem);
int ctl_grow_mem_pool(struct ctl_mem_pool *pool, int count,
int can_wait);
int ctl_shrink_mem_pool(struct ctl_mem_pool *pool);
#endif /* _KERNEL */
#endif /* _CTL_MEMPOOL_H_ */