Gleb Chesnokov
45d3123fe4
Make scst_vdisk and scst_user composite modules so KUnit can link additional objects without including test sources. Rename the implementation files while preserving the module names and update source-path consumers. Move existing private command and device layouts into local headers without changing their fields, constants or logic. No installed interface is expanded.
2.1 KiB
SCST User-Space Programs
Ownership and interfaces
This directory owns C programs that consume SCST kernel/user interfaces:
fileio/implements a user-space device handler over/dev/scst_user.scst/include/scst_user.handscst/src/dev_handlers/scst_user_main.cown the kernel side of that ABI.stpgd/consumes SCST events and dispatches ALUA state transitions throughscst_on_stpg.events/is a small event-API example and is not part of the defaultusr/Makefilebuild/install set.scst/include/scst_event.handscst/src/scst_event.cown the event ABI.
These programs do not own generic SCST configuration, backend kernel handler semantics, or target transport protocols.
Change boundaries
- Update user and kernel producers/consumers together for any ioctl, event, structure layout, command/subcommand, flag, error, or version change. Keep fixed-width types, 32/64-bit compatibility, interface versioning where present, and ownership/reuse rules for shared buffers and commands.
- For
fileio, trace registration, memory mapping/allocation, command receive, execution, completion, exception, abort, and unregister paths before changing lifetime behavior. Use current code anddoc/scst_user_spec.sgml; do not rely on the document alone. - For
stpgd, treat event filtering and the external helper invocation as a cluster/control boundary. Changes may alter ALUA state on multiple nodes.
Generated files, validation, and safety
fileio_tgt, stpgd, the optional events binary, .depend*, objects, and
installed files are generated artifacts. Build through usr/Makefile or the
focused top-level make usr; the default build covers fileio and stpgd,
not events. These programs use CC directly; kernel ARCH and
CROSS_COMPILE settings do not by themselves select a user-space cross
compiler. There is no local unit-test target.
Do not run these programs against /dev/scst_user, install them, invoke
scst_on_stpg, or change ALUA/cluster state without explicit authorization.
Do not point a handler at a real backing file or block device unless the exact
storage and destructive-test scope are approved.