This patch contains the squashed version of a number of cleanups and
minor fixes from Andy's initial series (round 1) for target core this
past spring.  The condensed log looks like:

target: use errno values instead of returning -1 for everything
target: Rename transport_calc_sg_num to transport_init_task_sg
target: Fix leak in error path in transport_init_task_sg
target/pscsi: Remove pscsi_get_sh() usage
target: Make two runtime checks into WARN_ONs
target: Remove hba queue depth and convert to spin_lock_irq usage
target: dev->dev_status_queue_obj is unused
target: Make struct se_queue_req.cmd type struct se_cmd *
target: Remove __transport_get_qr_from_queue()
target: Rename se_dev->g_se_dev_list to se_dev_node
target: Remove struct se_global
target: Simplify scsi mib index table code
target: Make dev_queue_obj a member of se_device instead of a pointer
target: remove extraneous returns at end of void functions
target: Ensure transport_dump_vpd_ident_type returns null-terminated str
target: Function pointers don't need to use '&' to be assigned
target: Fix comment in __transport_execute_tasks()
target: Misc style cleanups
target: rename struct pr_reservation_template to pr_reservation
target: Remove #defines that just perform indirection
target: Inline transport_get_task_from_execute_queue()
target: Minor header comment fixes
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch removes two instances of left over v3.x code performing local
scope access to struct target_core_fabric_ops->tf_subsys->su_group in
target_fabric_configfs_register() and target_fabric_configfs_deregister().
Reported-by: NChristophe Fergeau <cfergeau@gmail.com>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>

This patch fixes a number of cases in target core using an incorrectly

	if (strlen(foo) > SOME_MAX_SIZE)

As strlen() returns the number of characters in the string not counting
the NULL character at the end.  So if you do something like:

        char buf[10];

        if (strlen("0123456789") > 10)
                return -ETOOLONG;
        snprintf(buf, 10, "0123456789");
        printf("%s\n", buf);

then the last "9" gets chopped off and only "012345678" is printed.

Plus I threw in one small related cleanup.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In the original code, there were several places inside the
target_fabric_configfs_init() function that returned NULL on error
and one place the returned an ERR_PTR.  There are two places that
call this function and they only check for NULL returns; they don't
check for ERR_PTRs.  So I've changed the ERR_PTR so now the function
only returns NULL on error.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch converts transport_core_report_lun_response() to use
drivers/scsi/scsi_scan.c:int_to_scsilun instead of using the
struct target_core_fabric_ops->pack_lun() fabric provided API vector.

It also removes the tfo->pack_lun check from target_fabric_tf_ops_check()
and removes from struct target_core_fabric_ops->pack_lun() from
target_core_fabric_ops.h, and the following mainline scsi-misc fabric
modules:

*) tcm_loop: Drop tcm_loop_pack_lun() usage
*) tcm_fc: Drop ft_pack_lun() usage
Reported-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>

This patch converts transport_core_report_lun_response() to use
drivers/scsi/scsi_scan.c:int_to_scsilun instead of using the
struct target_core_fabric_ops->pack_lun() fabric provided API vector.

It also removes the tfo->pack_lun check from target_fabric_tf_ops_check()
and removes from struct target_core_fabric_ops->pack_lun() from
target_core_fabric_ops.h, and the following mainline scsi-misc fabric
modules:

*) tcm_loop: Drop tcm_loop_pack_lun() usage
*) tcm_fc: Drop ft_pack_lun() usage
Reported-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>

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: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This patch fixes the follownig section mismatch warning:

WARNING: vmlinux.o(.text+0x21617a): Section mismatch in reference from the
function target_core_init_configfs() to the function .init.text:rd_module_init()

The function target_core_init_configfs() references the function __init
rd_module_init().  This is often because target_core_init_configfs() lacks
a __init annotation or the annotation of rd_module_init is wrong.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This patch converts the target_core_store_dev_enable() -> struct
se_subsystem_api->create_virtdevice() call to return proper ERR_PTR values
back up to configfs logic during backend dependent struct se_device ENABLE
exception conditions.

Along with the change to target_core_configfs.c, this includes converting IBLOCK,
FILEIO, pSCSI, and RAMDISK_* backend subsystem plugins to obtain upper level
PTR_ERR return codes (where available), and return via ERR_PTR during a
*_create_virtdev() failure.
Reported-by: NFubo Chen <fubo.chen@gmail.com>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

match_strdup() dynamically allocates memory and it is the responsabillity
of the caller to free that memory. The following three cases:

drivers/target/target_core_file.c:fd_set_configfs_dev_params()
drivers/target/target_core_iblock.c:iblock_set_configfs_dev_params()
drivers/target/target_core_configfs.c:target_core_dev_pr_store_attr_res_aptpl_metadata()

should be kfree()'ing the allocated memory once it is no longer needed.
It also makes sure to return -ENOMEM if the memory allocation in match_strdup()
should fail.  For target_core_configfs.c, this patch adds kfree()'s around
Opt_initiator_fabric, Opt_initiator_node, Opt_initiator_sid, Opt_sa_res_key,
Opt_target_fabric, and Opt_target_node for the Persistent Reservations
Activate Persistence across Target Power Loss (APTPL=1) token parsing.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This patch moves a large number of memory release paths inside of the
configfs callback target_core_hba_item_ops->release() called from
within fs/configfs/item.c: config_item_cleanup() context.  This patch
resolves the SLUB 'Poison overwritten' warnings.
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames 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: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This patch fixes two bugs uncovered during testing with
slub_debug=FPUZ during module_exit() -> target_core_exit_configfs()
with release of configfs subsystem consumer default groups, namely how
this should be working with
fs/configfs/dir.c:configfs_unregister_subsystem() release logic for
struct config_group->default_group.

The first issue involves configfs_unregister_subsystem() expecting to
walk+drain the top-level subsys->su_group.default_groups directly in
unlink_group(), and not directly from the configfs subsystem consumer
for the top level struct config_group->default_groups.  This patch
drops the walk+drain of subsys->su_group.default_groups from TCM
configfs subsystem consumer code, and moves the top-level
->default_groups kfree() after configfs_unregister_subsystem() has
been called.

The second issue involves calling
core_alua_free_lu_gp(se_global->default_lu_gp) to release the
default_lu_gp->lu_gp_group before configfs_unregister_subsystem() has
been called.  This patches also moves the core_alua_free_lu_gp() call
to release default_lu_group->lu_gp_group after the subsys has been
unregistered.

Finally, this patch explictly clears the
[lu_gp,alua,hba]_cg->default_groups pointers after kfree() to ensure
that no stale memory is picked up from child struct
config_group->default_group[] while configfs_unregister_subsystem() is
called.
Reported-by: NFubo Chen <fubo.chen@gmail.com>
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames 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: NNicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>