lpfc_scsi_prep_dma_buf_s4(9)

💅 lpfc_scsi_prep_dma_buf_s4 — a Kernel API Manual moment

okay so bestie, welcome to the Kernel API Manual, section 9, and today's main character is lpfc_scsi_prep_dma_buf_s4. yes that's a whole mouthful, we're gonna get through it together 🫶

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✨ NAME ✨

lpfc_scsi_prep_dma_buf_s4 — DMA mapping for scsi buffer to SLI4 IF spec

like, that's the whole vibe. it maps a scsi buffer's DMA situation to the SLI-4 interface spec. no cap. 💅

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🌸 SYNOPSIS 🌸

int lpfc_scsi_prep_dma_buf_s4 (struct lpfc_hba *phba , struct
lpfc_io_buf *lpfc_cmd );

it returns an int, it takes two pointers, and it's giving "small function, big responsibilities" energy fr fr ✨

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🎀 ARGUMENTS 🎀

• phba — The Hba for which this call is being executed. that's your host bus adapter, the whole reason we're here 👑
• lpfc_cmd — The scsi buffer which is going to be mapped. this is the little guy getting the DMA glow-up 🦋

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💖 DESCRIPTION 💖

so what does this routine actually do, you ask? okay so — it does the pci DMA mapping for the scatter-gather list of the scsi cmnd field of lpfc_cmd, and it does that for a device with the SLI-4 interface spec. that's it. that's the whole job. iconic behavior honestly 🌈

Return codes, and listen, these matter, do not skip them:

• 2 — Error — Do not retry
• 1 — Error — Retry
• 0 — Success

⚠️ okay bestie real talk, pay attention to that 2 — it literally says do not retry. do not be out here retrying a 2. that's not the vibe. 💀

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🧚 SEE ALSO 🧚

Kernel file ./drivers/scsi/lpfc/lpfc_scsi.c — the source, the origin story, the mothership 🌟

and now, the roll call. every single one of these. we don't leave a single reference behind, not on my watch 🫶

• lpfc_sli4_set_rsp_sgl_last(9)
• lpfc_rampdown_queue_depth(9)
• lpfc_ramp_down_queue_handler(9)
• lpfc_scsi_dev_block(9)
• lpfc_new_scsi_buf_s3(9)
• lpfc_sli4_vport_delete_fcp_xri_aborted(9)
• lpfc_sli4_io_xri_aborted(9)
• lpfc_get_scsi_buf_s3(9)
• lpfc_get_scsi_buf_s4(9)
• lpfc_get_scsi_buf(9)
• lpfc_release_scsi_buf_s3(9)
• lpfc_release_scsi_buf_s4(9)
• lpfc_release_scsi_buf(9)
• lpfc_fcpcmd_to_iocb(9)
• lpfc_scsi_prep_dma_buf_s3(9)
• lpfc_bg_err_inject(9)
• lpfc_sc_to_bg_opcodes(9)
• lpfc_bg_err_opcodes(9)
• lpfc_bg_setup_bpl(9)
• lpfc_bg_setup_bpl_prot(9)
• lpfc_bg_setup_sgl(9)
• lpfc_bg_setup_sgl_prot(9)
• lpfc_prot_group_type(9)
• lpfc_bg_scsi_adjust_dl(9)
• lpfc_bg_scsi_prep_dma_buf_s3(9)
• lpfc_bg_scsi_prep_dma_buf_s4(9)
• lpfc_scsi_prep_dma_buf(9)
• lpfc_bg_scsi_prep_dma_buf(9)
• lpfc_scsi_prep_cmnd_buf(9)
• lpfc_send_scsi_error_event(9)
• lpfc_scsi_unprep_dma_buf(9)
• lpfc_unblock_requests(9)
• lpfc_block_requests(9)
• lpfc_update_cmf_cmpl(9)
• lpfc_update_cmf_cmd(9)
• lpfc_handle_fcp_err(9)
• lpfc_fcp_io_cmd_wqe_cmpl(9)
• lpfc_scsi_cmd_iocb_cmpl(9)
• lpfc_scsi_prep_cmnd_buf_s3(9)
• lpfc_scsi_prep_cmnd_buf_s4(9)
• lpfc_scsi_prep_cmnd(9)
• lpfc_scsi_prep_task_mgmt_cmd_s3(9)
• lpfc_scsi_prep_task_mgmt_cmd_s4(9)
• lpfc_scsi_api_table_setup(9)
• lpfc_tskmgmt_def_cmpl(9)
• lpfc_check_pci_resettable(9)
• lpfc_info(9)
• lpfc_poll_rearm_timer(9)
• lpfc_poll_start_timer(9)
• lpfc_poll_timeout(9)
• lpfc_queuecommand(9)
• lpfc_abort_handler(9)
• lpfc_check_fcp_rsp(9)
• lpfc_send_taskmgmt(9)
• lpfc_chk_tgt_mapped(9)
• lpfc_reset_flush_io_context(9)
• lpfc_device_reset_handler(9)
• lpfc_target_reset_handler(9)
• lpfc_host_reset_handler(9)
• lpfc_sdev_init(9)
• lpfc_sdev_configure(9)
• lpfc_sdev_destroy(9)
• lpfc_create_device_data(9)
• lpfc_delete_device_data(9)
• __lpfc_get_device_data(9)
• lpfc_find_next_oas_lun(9)
• lpfc_enable_oas_lun(9)
• lpfc_disable_oas_lun(9)

like, that's the whole friend group. every one of them showed up to the party 🎉

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okay that's the page!! sourced straight from ./drivers/scsi/lpfc, dated October 2026 — so yeah, she's a little futuristic, we don't question it 💜 go map some DMA bestie, you got this 🦋✨