Commit graph

12 commits

Author SHA1 Message Date
Christoph Hellwig
0fd97ccf45 target: kill struct se_subsystem_dev
Simplify the code a lot by killing the superflous struct se_subsystem_dev.
Instead se_device is allocated early on by the backend driver, which allocates
it as part of its own per-device structure, borrowing the scheme that is for
example used for inode allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:43 -08:00
Andy Grover
44bfd01850 target/iblock: Add parameter to specify read-only devices
see https://bugzilla.redhat.com/show_bug.cgi?id=818855

Adds a parameter so read-only block devices may be registered as
LIO backstores.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-07-16 17:29:11 -07:00
Christoph Hellwig
5787cacd0b target: remove struct se_task
We can use struct se_cmd for everything it did.  Make sure to pass the S/G
list and data direction to the execution function to ease adding back BIDI
support later on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-05-06 15:11:26 -07:00
Christoph Hellwig
d5b4a21b3d target: increase iblock task sizes
There is no real limit for task sizes in the iblock driver given that we
can chain bios.  Increase the maximum size to UINT_MAX, and change the
code to submit bios in a smaller batch size to avoid deadlocks when
having more bios in flight than the pool supports.  Also increase the
pool size to always allow multiple tasks to be in flight.

I also had to change the task refcounting to include one reference for
the submission task, which is a standard practice in this kind of code
in Linux (e.g. XFS I/O submission).  This was wrong before, but couldn't
be hit easily.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:46 -08:00
Christoph Hellwig
6e315a066d target: remove the unused struct iblock_hba
There is no reason to allocate a struct just to store the host number for
a debug printk in the detach path.  I've simply removed the verbose
debugging given that the calling code thinks the number passed in is
something different from a host ID anyway.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:46 -08:00
Christoph Hellwig
6193f06e6f target: make the ->get_cdb method optional
The most commonly used file, iblock and rd backends have no use for
a per-task CDB and thus don't need a method to copy it into their
otherwise unused CDB fields.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:11 +00:00
Christoph Hellwig
dbbf3e94c2 target: cleanup iblock bio submission
Move the entirely bio allocation, mapping and submission into ->do_task.
This

 a) avoids blocking the I/O submission thread unessecarily, and
 b) simplifies the code greatly

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:43 +00:00
Andy Grover
6708bb27bb target: Follow up core updates from AGrover and HCH (round 4)
This patch contains the squashed version of forth round series cleanups
from Andy and Christoph following the post heavy lifting in the preceeding:
'Eliminate usage of struct se_mem' and 'Make all control CDBs scatter-gather'
changes.  This also includes a conversion of target core and the v3.0
mainline fabric modules (loopback and tcm_fc) to use pr_debug and the
CONFIG_DYNAMIC_DEBUG infrastructure!

These have been squashed into this third and final round for v3.1.

target: Remove ifdeffed code in t_g_process_write
target: Remove direct ramdisk code
target: Rename task_sg_num to task_sg_nents
target: Remove custom debug macros for pr_debug. Use pr_err().
target: Remove custom debug macros in mainline fabrics
target: Set WSNZ=1 in block limits VPD. Abort if WRITE_SAME sectors = 0
target: Remove transport do_se_mem_map callback
target: Further simplify transport_free_pages
target: Redo task allocation return value handling
target: Remove extra parentheses
target: change alloc_task call to take *cdb, not *cmd

(nab: Fix bogus struct file assignments in fd_do_readv and fd_do_writev)

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Roland Dreier
21bca31c96 target/iblock: Remove unused iblock_dev members
ibd_depth and ibd_force are used write-only.  Remove them.
ibd_major/minor can be easily retrieved from ibd_bd, so get
rid of them too.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:46 +00:00
Nicholas Bellinger
8f3d14e2b0 target/iblock: Use request_queue->nr_request for se_device defaults
This patch converts iblock_create_virtdevice() to use request_queue->nr_request
for se_dev_limits usage of ->hw_queue_depth and ->queue_depth for individual
struct se_device export.

It also removes the now unused defines for IBLOCK_DEVICE_QUEUE_DEPTH and
IBLOCK_MAX_DEVICE_QUEUE_DEPTH

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:45 +00:00
Andy Grover
e3d6f909ed target: Core cleanups from AGrover (round 1)
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: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:43 +00:00
Nicholas Bellinger
c66ac9db8d [SCSI] target: Add LIO target core v4.0.0-rc6
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>
2011-01-14 10:12:29 -06:00