kernel/linux.git/include/target, branch master

scsi: target: Add support for completing commands from backend context

2026-03-01T02:04:02+00:00

To complete a command several drivers just drop their reference and add it to list to be processed by a driver specific thread. So there's no need to go from backend context to the LIO thread then to the driver's thread. When avoiding the LIO thread, IOPS can increase from 20-30% for workloads like: fio --filename=/dev/sdb --direct=1 --rw=randrw --bs=8K \ --ioengine=libaio --iodepth=128 --numjobs=$jobs where increasing jobs increases the performance improvement (this is using NVMe drives with LIO's submit_type=1 to directly submit). Add the infrastructure so drivers and userspace can control how to complete a command like is done for the submission path. In this commit there is no behavior change and we continue to defer to the LIO workqueue thread. In the subsequent commits we will allow drivers to report what they support and allow userspace to control the behavior. Signed-off-by: Mike Christie Link: https://patch.msgid.link/20260222232946.7637-2-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: core: Add emulation for REPORT IDENTIFYING INFORMATION

2025-12-17T02:07:22+00:00

Add emulation for REPORT IDENTIFYING INFORMATION command using the configfs file 'pd_text_id_info' in target core module. The configfs file is created in /sys/kernel/config/target/core// /wwn/. An emulation function, spc_emulate_report_id_info(), is defined to return the identification string based on the contents of 'pd_text_id_info'. The details of the REPORT IDENTIFYING INFORMATION command is defined in section 6.32 of SPC4. [mkp: checkpatch tweaks] Signed-off-by: Gulam Mohamed Reviewed-by: John Garry Link: https://patch.msgid.link/20251201110716.227588-1-gulam.mohamed@oracle.com Signed-off-by: Martin K. Petersen

Merge patch series "target: RW/num_cmds stats improvements"

2025-11-03T03:07:27+00:00

Mike Christie says: The following patches were made over Linus tree. They fix/improve the stats used in the main IO path. The first patch fixes an issue where I made some stats u32 when they should have stayed u64. The rest of the patches improve the handling of RW/num_cmds stats to reduce code duplication and improve performance. Link: https://patch.msgid.link/20250917221338.14813-1-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Move LUN stats to per-CPU

2025-11-03T03:06:12+00:00

The atomic use in the main I/O path is causing perf issues when using higher performance backend devices and multiple queues (more than 10 when using vhost-scsi) like with this fio workload: [global] bs=4K iodepth=128 direct=1 ioengine=libaio group_reporting time_based runtime=120 name=standard-iops rw=randread numjobs=16 cpus_allowed=0-15 To fix this issue, move the LUN stats to per CPU. Note: I forgot to include this patch with the delayed/ordered per CPU tracking and per device/device entry per CPU stats. With this patch you get the full 33% improvements when using fast backends, multiple queues and multiple IO submiters. Signed-off-by: Mike Christie Reviewed-by: Dmitry Bogdanov Link: https://patch.msgid.link/20250917221338.14813-4-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Fix LUN/device R/W and total command stats

2025-11-03T03:06:11+00:00

In commit 9cf2317b795d ("scsi: target: Move I/O path stats to per CPU") I saw we sometimes use %u and also misread the spec. As a result I thought all the stats were supposed to be 32-bit only. However, for the majority of cases we support currently, the spec specifies u64 bit stats. This patch converts the stats changed in the commit above to u64. Fixes: 9cf2317b795d ("scsi: target: Move I/O path stats to per CPU") Signed-off-by: Mike Christie Reviewed-by: Dmitry Bogdanov Link: https://patch.msgid.link/20250917221338.14813-2-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Add WRITE_ATOMIC_16 handler

2025-11-03T02:40:02+00:00

Add the core LIO code to process the WRITE_ATOMIC_16 command. Signed-off-by: Mike Christie jpg: fix return code from sbc_check_atomic, reformat Signed-off-by: John Garry Link: https://patch.msgid.link/20251020103820.2917593-5-john.g.garry@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Add helper to set up atomic values from block_device

2025-11-03T02:40:01+00:00

Add a helper function that sets up the atomic value based on a block_device similar to what we do for unmap. Signed-off-by: Mike Christie jpg: Set atomic alignment, drop atomic_supported reference Signed-off-by: John Garry Link: https://patch.msgid.link/20251020103820.2917593-4-john.g.garry@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Add atomic se_device fields

2025-11-03T02:40:01+00:00

Add atomic fields to the se_device and export them in configfs. Initially only target_core_iblock will be supported and we will inherit all the settings from the block layer. Signed-off-by: Mike Christie jpg: Stop being allowed to configure atomic write alignment, Signed-off-by: John Garry Link: https://patch.msgid.link/20251020103820.2917593-3-john.g.garry@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Rename target_configure_unmap_from_queue()

2025-11-03T02:40:01+00:00

Rename target_configure_unmap_from_queue() to target_configure_unmap_from_bdev() since it now takes a bdev. Signed-off-by: Mike Christie Signed-off-by: John Garry Reviewed-by: John Garry Link: https://patch.msgid.link/20251020103820.2917593-2-john.g.garry@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: core: Constify enabled() in struct target_opcode_descriptor

2025-05-21T02:11:03+00:00

Constify the first argument of the enabled() function in struct target_opcode_descriptor. This is the first step in order to constify struct target_opcode_descriptor. Signed-off-by: Christophe JAILLET Link: https://lore.kernel.org/r/4290cf1dbe100c1b1edf2ede5e5aef19b04ee7f2.1747592774.git.christophe.jaillet@wanadoo.fr Signed-off-by: Martin K. Petersen