linux.git/drivers/target/target_core_file.c, branch v5.8

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Richard Fontana 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman

iov_iter: Separate type from direction and use accessor functions

2018-10-23T23:41:07+00:00

In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells

scsi: target: target/file: Add support of direct and async I/O

2018-05-15T02:40:08+00:00

There are two advantages:

* Direct I/O allows to avoid the write-back cache, so it reduces affects
  to other processes in the system.
* Async I/O allows to handle a few commands concurrently.

DIO + AIO shows a better perfomance for random write operations:

Mode: O_DSYNC Async: 1
$ ./fio --bs=4K --direct=1 --rw=randwrite --ioengine=libaio --iodepth=64 --name=/dev/sda --runtime=20 --numjobs=2
  WRITE: bw=45.9MiB/s (48.1MB/s), 21.9MiB/s-23.0MiB/s (22.0MB/s-25.2MB/s), io=919MiB (963MB), run=20002-20020msec

Mode: O_DSYNC Async: 0
$ ./fio --bs=4K --direct=1 --rw=randwrite --ioengine=libaio --iodepth=64 --name=/dev/sdb --runtime=20 --numjobs=2
  WRITE: bw=1607KiB/s (1645kB/s), 802KiB/s-805KiB/s (821kB/s-824kB/s), io=31.8MiB (33.4MB), run=20280-20295msec

Known issue:

DIF (PI) emulation doesn't work when a target uses async I/O, because
DIF metadata is saved in a separate file, and it is another non-trivial
task how to synchronize writing in two files, so that a following read
operation always returns a consisten metadata for a specified block.

Cc: "Nicholas A. Bellinger" 
Cc: Christoph Hellwig 
Cc: Bryant G. Ly 
Tested-by: Bryant G. Ly 
Signed-off-by: Andrei Vagin 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Bryant G. Ly 
Reviewed-by: Mike Christie 
Signed-off-by: Martin K. Petersen

target/file: Do not return error for UNMAP if length is zero

2017-11-04T21:45:16+00:00

The function fd_execute_unmap() in target_core_file.c calles

ret = file->f_op->fallocate(file, mode, pos, len);

Some filesystems implement fallocate() to return error if
length is zero (e.g. btrfs) but according to SCSI Block
Commands spec UNMAP should return success for zero length.

Signed-off-by: Jiang Yi 
Signed-off-by: Nicholas Bellinger

fs: fix kernel_write prototype

2017-09-04T23:05:15+00:00

Make the position an in/out argument like all the other read/write
helpers and and make the buf argument a void pointer.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

2017-07-13T21:27:32+00:00

Pull SCSI target updates from Nicholas Bellinger:
 "It's been usually busy for summer, with most of the efforts centered
  around TCMU developments and various target-core + fabric driver bug
  fixing activities. Not particularly large in terms of LoC, but lots of
  smaller patches from many different folks.

  The highlights include:

   - ibmvscsis logical partition manager support (Michael Cyr + Bryant
     Ly)

   - Convert target/iblock WRITE_SAME to blkdev_issue_zeroout (hch +
     nab)

   - Add support for TMR percpu LUN reference counting (nab)

   - Fix a potential deadlock between EXTENDED_COPY and iscsi shutdown
     (Bart)

   - Fix COMPARE_AND_WRITE caw_sem leak during se_cmd quiesce (Jiang Yi)

   - Fix TMCU module removal (Xiubo Li)

   - Fix iser-target OOPs during login failure (Andrea Righi + Sagi)

   - Breakup target-core free_device backend driver callback (mnc)

   - Perform TCMU add/delete/reconfig synchronously (mnc)

   - Fix TCMU multiple UIO open/close sequences (mnc)

   - Fix TCMU CHECK_CONDITION sense handling (mnc)

   - Fix target-core SAM_STAT_BUSY + TASK_SET_FULL handling (mnc + nab)

   - Introduce TYPE_ZBC support in PSCSI (Damien Le Moal)

   - Fix possible TCMU memory leak + OOPs when recalculating cmd base
     size (Xiubo Li + Bryant Ly + Damien Le Moal + mnc)

   - Add login_keys_workaround attribute for non RFC initiators (Robert
     LeBlanc + Arun Easi + nab)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (68 commits)
  iscsi-target: Add login_keys_workaround attribute for non RFC initiators
  Revert "qla2xxx: Fix incorrect tcm_qla2xxx_free_cmd use during TMR ABORT"
  tcmu: clean up the code and with one small fix
  tcmu: Fix possbile memory leak / OOPs when recalculating cmd base size
  target: export lio pgr/alua support as device attr
  target: Fix return sense reason in target_scsi3_emulate_pr_out
  target: Fix cmd size for PR-OUT in passthrough_parse_cdb
  tcmu: Fix dev_config_store
  target: pscsi: Introduce TYPE_ZBC support
  target: Use macro for WRITE_VERIFY_32 operation codes
  target: fix SAM_STAT_BUSY/TASK_SET_FULL handling
  target: remove transport_complete
  pscsi: finish cmd processing from pscsi_req_done
  tcmu: fix sense handling during completion
  target: add helper to copy sense to se_cmd buffer
  target: do not require a transport_complete for SCF_TRANSPORT_TASK_SENSE
  target: make device_mutex and device_list static
  tcmu: Fix flushing cmd entry dcache page
  tcmu: fix multiple uio open/close sequences
  tcmu: drop configured check in destroy
  ...

target: break up free_device callback

2017-07-07T06:11:37+00:00

With this patch free_device is now used to free what is allocated in the
alloc_device callback and destroy_device tears down the resources that are
setup in the configure_device callback.

This patch will be needed in the next patch where tcmu needs
to be able to look up the device in the destroy callback.

Signed-off-by: Mike Christie 
Reviewed-by: Bart Van Assche 
Signed-off-by: Nicholas Bellinger

fs: implement vfs_iter_write using do_iter_write

2017-06-29T21:49:23+00:00

De-dupliate some code and allow for passing the flags argument to
vfs_iter_write.  Additionally it now properly updates timestamps.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

fs: implement vfs_iter_read using do_iter_read

2017-06-29T21:49:23+00:00

De-dupliate some code and allow for passing the flags argument to
vfs_iter_read.  Additional it properly updates atime now.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

target/fileio: Fix zero-length READ and WRITE handling

2017-05-07T23:05:16+00:00

This patch fixes zero-length READ and WRITE handling in target/FILEIO,
which was broken a long time back by:

Since:

  commit d81cb44726f050d7cf1be4afd9cb45d153b52066
  Author: Paolo Bonzini 
  Date:   Mon Sep 17 16:36:11 2012 -0700

      target: go through normal processing for all zero-length commands

which moved zero-length READ and WRITE completion out of target-core,
to doing submission into backend driver code.

To address this, go ahead and invoke target_complete_cmd() for any
non negative return value in fd_do_rw().

Signed-off-by: Bart Van Assche 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Christoph Hellwig 
Cc: Andy Grover 
Cc: David Disseldorp 
Cc:  # v3.7+
Signed-off-by: Nicholas Bellinger