scsi_device_block(9)

💖 NAME 💖

okay so bestie, this is scsi_device_block from the Kernel API Manual — and her whole thing is: try to transition to the SDEV_BLOCK state. that's the name, that's the mission, no cap. 💅

✨ SYNOPSIS ✨

void scsi_device_block (struct scsi_device *sdev , void *data );

🎀 ARGUMENTS 🎀

• sdev — the device to block, bestie. that's the one getting the pause vibe.
• data — dummy argument, ignored. literally just there for the function signature. 🙈

🦋 DESCRIPTION 🦋

okay so what this icon does: it pauses SCSI command processing on the specified device. it's giving main character pause-button energy, fr fr.

and the important part — callers must wait until all ongoing scsi_queue_rq calls have finished after this function returns. like, after this function returns, do not just assume the coast is clear; wait for every ongoing scsi_queue_rq call to wrap up. periodt. 🔥

💀 NOTE 💀

this routine transitions the device to the SDEV_BLOCK state — and that transition must be a legal transition. lowkey no sketchy state jumps, iykyk. when the device is in this state, command processing is paused until the device leaves the SDEV_BLOCK state.

see also scsi_internal_device_unblock. 🫶

🌈 SEE ALSO 🌈

kernel file: ./drivers/scsi/scsi_lib.c — and the whole linked-up squad is: __scsi_queue_insert(9), scsi_queue_insert(9), scsi_failures_reset_retries(9), scsi_check_passthrough(9), scsi_execute_cmd(9), scsi_run_queue(9), scsi_result_to_blk_status(9), scsi_rq_err_bytes(9), scsi_io_completion(9), scsi_alloc_sgtables(9), scsi_initialize_rq(9), scsi_alloc_request(9), scsi_dispatch_cmd(9), scsi_get_internal_cmd(9), scsi_put_internal_cmd(9), scsi_device_from_queue(9), scsi_block_requests(9), scsi_unblock_requests(9), scsi_mode_select(9), scsi_mode_sense(9), scsi_test_unit_ready(9), scsi_device_set_state(9), scsi_evt_emit(9), scsi_evt_thread(9), sdev_evt_send(9), sdev_evt_alloc(9), sdev_evt_send_simple(9), scsi_device_quiesce(9), scsi_device_resume(9), scsi_internal_device_block_nowait(9), scsi_internal_device_unblock_nowait(9), scsi_internal_device_unblock(9), scsi_block_targets(9), scsi_host_block(9), scsi_kmap_atomic_sg(9), scsi_kunmap_atomic_sg(9), scsi_vpd_lun_id(9), scsi_vpd_lun_serial(9), scsi_vpd_tpg_id(9), scsi_build_sense(9).

xoxo, your kernel bestie 💋 — source/version vibes from ./drivers/scsi, date October 2026, and yes she ate. 💖