Add a LIO storage engine that presents commands to userspace for execution.
This would allow more complex backstores to be implemented out-of-kernel,
and also make experimentation a-la FUSE (but at the SCSI level -- "SUSE"?)
possible.
It uses a mmap()able UIO device per LUN to share a command ring and data
area. The commands are raw SCSI CDBs and iovs for in/out data. The command
ring is also reused for returning scsi command status and optional sense
data.
This implementation is based on Shaohua Li's earlier version but heavily
modified. Differences include:
* Shared memory allocated by kernel, not locked-down user pages
* Single ring for command request and response
* Offsets instead of embedded pointers
* Generic SCSI CDB passthrough instead of per-cmd specialization in ring
format.
* Uses UIO device instead of anon_file passed in mailbox.
* Optional in-kernel handling of some commands.
The main reason for these differences is to permit greater resiliency
if the user process dies or hangs.
Things not yet implemented (on purpose):
* Zero copy. The data area is flexible enough to allow page flipping or
backend-allocated pages to be used by fabrics, but it's not clear these
are performance wins. Can come later.
* Out-of-order command completion by userspace. Possible to add by just
allowing userspace to change cmd_id in rsp cmd entries, but currently
not supported.
* No locks between kernel cmd submission and completion routines. Sounds
like it's possible, but this can come later.
* Sparse allocation of mmaped area. Current code vmallocs the whole thing.
If the mapped area was larger and not fully mapped then the driver would
have more freedom to change cmd and data area sizes based on demand.
Current code open issues:
* The use of idrs may be overkill -- we maybe can replace them with a
simple counter to generate cmd_ids, and a hash table to get a cmd_id's
associated pointer.
* Use of a free-running counter for cmd ring instead of explicit modulo
math. This would require power-of-2 cmd ring size.
(Add kconfig depends NET - Randy)
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds support for EXTENDED_COPY emulation from SPC-3, that
enables full copy offload target support within both a single virtual
backend device, and across multiple virtual backend devices. It also
functions independent of target fabric, and supports copy offload
across multiple target fabric ports.
This implemenation supports both EXTENDED_COPY PUSH and PULL models
of operation, so the actual CDB may be received on either source or
desination logical unit.
For Target Descriptors, it currently supports the NAA IEEE Registered
Extended designator (type 0xe4), which allows the reference of target
ports to occur independent of fabric type using EVPD 0x83 WWNs.
For Segment Descriptors, it currently supports copy from block to
block (0x02) mode.
It also honors any present SCSI reservations of the destination target
port. Note that only Supports No List Identifier (SNLID=1) mode is
supported.
Also included is basic RECEIVE_COPY_RESULTS with service action type
OPERATING PARAMETERS (0x03) required for SNLID=1 operation.
v3 changes:
- Fix incorrect return type in target_do_receive_copy_results()
(Fengguang)
v2 changes:
- Use target_alloc_sgl() instead of transport_generic_get_mem()
- Convert debug output to use pr_debug()
- Convert target_xcopy_parse_target_descriptors() NAA IEEN WWN
dump to use 0x%16phN format specification
- Drop unnecessary xcopy_pt_cmd->xpt_passthrough_wsem, and
associated usage in xcopy_pt_write_pending() and
target_xcopy_issue_pt_cmd()
- Add check for unsupported EXTENDED_COPY(LID4) service action
bits in target_do_xcopy()
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Zach Brown <zab@redhat.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
Move the existing code in target_core_cdb.c into the files for the command
sets that the emulations implement.
(roland + nab: Squash patch: Fix range calculation in WRITE SAME emulation
when num blocks == 0s)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Instead of trying to handle all SCSI command sets in one function
(transport_generic_cmd_sequencer) call out to the backend driver to perform
this functionality. For pSCSI a copy of the existing code is used, but for
all virtual backends we can use a new parse_sbc_cdb helper is used to
provide a simple SBC emulation.
For now this setups means a fair amount of duplication between pSCSI and the
SBC library, but patches later in this series will sort out that problem.
(nab: Fix up build failure in target_core_pscsi.c)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The FireWire SBP-2 Target is a driver for using an IEEE-1394 connection
as a SCSI transport. This module uses the SCSI Target framework to
expose LUNs to other machines attached to a FireWire bus, in effect
acting as a FireWire hard disk similar to FireWire Target Disk mode
on many Apple computers.
This commit contains the squashed pull from Chris Boot's SBP-2-Target:
https://github.com/bootc/Linux-SBP-2-Target.git patch-v3
firewire-sbp-target: Add sbp_base.h header
firewire-sbp-target: Add sbp_configfs.c
firewire-sbp-target: Add sbp_fabric.{c,h}
firewire-sbp-target: Add sbp_management_agent.{c,h}
firewire-sbp-target: Add sbp_login.{c,h}
firewire-sbp-target: Add sbp_target_agent.{c,h}
firewire-sbp-target: Add sbp_scsi_cmnd.{c,h}
firewire-sbp-target: Add to target Kconfig and Makefile
Also add bootc's entry to the MAINTAINERS file. Great work Chris !!
Signed-off-by: Chris Boot <bootc@bootc.net>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Add a switch statement implementing the CDB LBA/len update directly
in target_get_task_cdb and remove the old ->transport_split_cdb
callback and all its implementations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The Linux-iSCSI.org target module is a full featured in-kernel
software implementation of iSCSI target mode (RFC-3720) for the
current WIP mainline target v4.1 infrastructure code for the v3.1
kernel. More information can be found here:
http://linux-iscsi.org/wiki/ISCSI
This includes support for:
* RFC-3720 defined request / response state machines and support for
all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi
include/scsi/iscsi_proto.h PDU definitions
* Target v4.1 compatible control plane using the generic layout in
target_core_fabric_configfs.c and fabric dependent attributes
within /sys/kernel/config/target/iscsi/ subdirectories.
* Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS)
* Support for IPv6 and IPv4 network portals in M:N mapping to TPGs
* iSCSI Error Recovery Hierarchy support
* Per iSCSI connection RX/TX thread pair scheduling affinity
* crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto
* CHAP Authentication support using libcrypto
* Conversion to use internal SGl allocation with iscsit_alloc_buffs() ->
transport_generic_map_mem_to_cmd()
(nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit:
iscsi: Use struct scsi_lun in iscsi structs instead of u8[8])
(nab: Fix 32-bit compile warnings)
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Grover <agrover@redhat.com>
Acked-by: Roland Dreier <roland@kernel.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
This is a comprehensive patch for FC-FC4 provider. tcm_fc is a FC-FC4
provider which glues target core (TCM) with Fiber channel library
(libfc). tcm_fc uses existing FC4 provider hooks from Fiber channel
library. This Fiber channel library is used by FCoE (transport - FC
over Ethernet) protocol driver as well.
Combination of modules such as Fiber channel library, tcm_fc, TCM
target core, and FCoE protocol driver enables functional FCoE target.
This patch includes initial commit for tcm_fc plus additional
enhancement, bug fixes.
This tcm_fc module essentially contains 3 entry points such as "prli",
"prlo", "recv". When process login request (ELS_PRLI) request is
received, Fiber channel library (libfc) module calls passive providers
(FC-FC4, tcm_fc) (if any registered) "prli" function. Likewise when
LOGO request is received, "prlo" function of passive provider is
invoked by libfc. For all other request (e.g. any read/write, task
management, LUN inquiry commands), "recv" function of passiver
provider is invoked by libfc. Those passive providers "prli, prlo,
recv" functions interact with TCM target core for requested operation.
This module was primarily developed by "Joe Eykholt" and there were
significant contributions from the people listed under signed-off.
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Acked-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch adds the TCM_Loop Linux/SCSI LLD fabric module for
accessing TCM device backstores as locally accessable SCSI LUNs in
virtual SAS, FC, and iSCSI Target ports using the generic fabric
TransportID and Target Port WWN naming handlers from TCM's
target_core_fabric_lib.c The TCM_Loop module uses the generic fabric
configfs infratructure provided by target_core_fabric_configfs.c and
adds a module dependent attribute for the creation/release of the
virtual I_T Nexus connected the TCM_Loop Target and Initiator Ports.
TCM_Loop can also be used with scsi-generic and BSG drivers so that
STGT userspace fabric modules, QEMU-KVM and other hypervisor SCSI
passthrough support can access TCM device backstore and control CDB
emulation.
For more information please see:
http://linux-iscsi.org/wiki/Tcm_loop
[jejb: fixed up checkpatch stuff]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch adds a target_core_mib.c statistics conversion for
backend context struct se_subsystem_dev + struct se_device config_group
based statistics in target_core_device.c using CONFIGFS_EATTR()
based struct config_item_types from target_core_stat.c code.
The conversion from backend /proc/scsi_target/mib/ context output to configfs
default groups+attributes include scsi_dev, scsi_lu, and scsi_tgt_dev output
from within individual:
/sys/kernel/config/target/core/$HBA/DEV/
The legacy procfs output now appear as individual configfs attributes under:
*) $HBA/$DEV/statistics/scsi_dev:
|-- indx
|-- inst
|-- ports
`-- role
*) $HBA/$DEV/statistics/scsi_lu:
|-- creation_time
|-- dev
|-- dev_type
|-- full_stat
|-- hs_num_cmds
|-- indx
|-- inst
|-- lu_name
|-- lun
|-- num_cmds
|-- prod
|-- read_mbytes
|-- resets
|-- rev
|-- state_bit
|-- status
|-- vend
`-- write_mbytes
*) $HBA/$DEV/statistics/scsi_tgt_dev:
|-- indx
|-- inst
|-- non_access_lus
|-- num_lus
|-- resets
`-- status
The conversion from backend /proc/scsi_target/mib/ context output to configfs
default groups+attributes include scsi_port, scsi_tgt_port and scsi_transport
output from within individual:
/sys/kernel/config/target/fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/
The legacy procfs output now appear as individual configfs attributes under:
*) fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/scsi_port
|-- busy_count
|-- dev
|-- indx
|-- inst
`-- role
*) fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/scsi_tgt_port
|-- dev
|-- hs_in_cmds
|-- in_cmds
|-- indx
|-- inst
|-- name
|-- port_index
|-- read_mbytes
`-- write_mbytes
*) fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/scsi_transport
|-- dev_name
|-- device
|-- indx
`-- inst
The conversion from backend /proc/scsi_target/mib/ context output to configfs
default groups+attributes include scsi_att_intr_port and scsi_auth_intr output
from within individual:
/sys/kernel/config/target/fabric/$WWN/tpgt_$TPGT/acls/$INITIATOR_WWN/lun_$LUN_ID/statistics/
The legacy procfs output now appear as individual configfs attributes under:
*) acls/$INITIATOR_WWN/lun_$LUN_ID/statistics/scsi_att_intr_port
|-- dev
|-- indx
|-- inst
|-- port
|-- port_auth_indx
`-- port_ident
*) acls/$INITIATOR_WWN/lun_$LUN_ID/statistics/scsi_auth_intr
|-- att_count
|-- creation_time
|-- dev
|-- dev_or_port
|-- hs_num_cmds
|-- indx
|-- inst
|-- intr_name
|-- map_indx
|-- num_cmds
|-- port
|-- read_mbytes
|-- row_status
`-- write_mbytes
Also, this includes adding struct target_fabric_configfs_template->
tfc_wwn_fabric_stats_cit and ->tfc_tpg_nacl_stat_cit respectively for
use during target_core_fabric_configfs.c:target_fabric_setup_cits()
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Add the current directory is superflous in general, and no includes in
drivers/scsi are needed either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch removes the legacy procfs based target_core_mib.c code,
and moves the necessary scsi_index_tables functions and defines into
target_core_transport.c and target_core_base.h code to allow existing
fabric independent statistics to function.
This includes the removal of a handful of 'atomic_t mib_ref_count'
counters used in struct se_node_acl, se_session and se_hba to prevent
removal while using seq_list procfs walking logic.
[jejb: fix up compile failures]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
LIO target is a full featured in-kernel target framework with the
following feature set:
High-performance, non-blocking, multithreaded architecture with SIMD
support.
Advanced SCSI feature set:
* Persistent Reservations (PRs)
* Asymmetric Logical Unit Assignment (ALUA)
* Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S)
* Full Error Recovery (ERL=0,1,2)
* Active/active task migration and session continuation (ERL=2)
* Thin LUN provisioning (UNMAP and WRITE_SAMExx)
Multiprotocol target plugins
Storage media independence:
* Virtualization of all storage media; transparent mapping of IO to LUNs
* No hard limits on number of LUNs per Target; maximum LUN size ~750 TB
* Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc.
Standards compliance:
* Full compliance with IETF (RFC 3720)
* Full implementation of SPC-4 PRs and ALUA
Significant code cleanups done by Christoph Hellwig.
[jejb: fix up for new block bdev exclusive interface. Minor fixes from
Randy Dunlap and Dan Carpenter.]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
