lpfc_bsg_diag_loopback_run(9)

💖 lpfc_bsg_diag_loopback_run(9) 💖

okay so bestie, welcome to the Kernel API Manual page for lpfc_bsg_diag_loopback_run — yes that's a whole mouthful, yes I say it in one breath, no you don't have to. This is the gen-z translation, but like... all the facts are still here, promise. 🫶

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✨ NAME ✨

lpfc_bsg_diag_loopback_run — run loopback on a port by issue ct cmd to itself 💅

🌸 SYNOPSIS 🌸

int lpfc_bsg_diag_loopback_run (struct bsg_job *job );

🎀 ARGUMENTS 🎀

• job — the LPFC_BSG_VENDOR_DIAG_TEST fc_bsg_job, aka the little container holding your whole request. it's giving "main character energy" honestly.

🦋 DESCRIPTION 🦋

so what does this icon actually do? it receives a user data buffer that's gonna be transmitted and received on the same port — yes, the port talking to itself, we love a self-sufficient queen 👑. heads up though: the link must be up and already in loopback mode before you call this. no loopback, no vibes. 😭

here's the whole little ritual, step by step:

1. A kernel buffer is allocated to copy the user data into.
2. The port registers with "itself".
3. The transmit and receive exchange ids are obtained.
4. The receive exchange id is posted.
5. A new els loopback event is created.
6. The command and response iocbs are allocated.
7. The cmd iocb FsType is set to elx loopback and the CmdRsp to looppback.

and that's the whole glow-up sequence ✨

lowkey important: this function is meant to be called n times while the port is in loopback, so it is the apps responsibility to issue a reset to take the port out of loopback mode. like, the function will not do it for you, bestie — you gotta clean up after yourself. periodt. 💀

⭐ SEE ALSO ⭐

Kernel file ./drivers/scsi/lpfc/lpfc_bsg.c

and the whole squad, in order, because nobody gets left behind 🫶:

• lpfc_bsg_send_mgmt_cmd_cmp(9)
• lpfc_bsg_send_mgmt_cmd(9)
• lpfc_bsg_rport_els_cmp(9)
• lpfc_bsg_rport_els(9)
• lpfc_bsg_event_free(9)
• lpfc_bsg_event_ref(9)
• lpfc_bsg_event_unref(9)
• lpfc_bsg_event_new(9)
• diag_cmd_data_free(9)
• lpfc_bsg_ct_unsol_abort(9)
• lpfc_bsg_hba_set_event(9)
• lpfc_bsg_hba_get_event(9)
• lpfc_issue_ct_rsp_cmp(9)
• lpfc_issue_ct_rsp(9)
• lpfc_bsg_send_mgmt_rsp(9)
• lpfc_bsg_diag_mode_enter(9)
• lpfc_bsg_diag_mode_exit(9)
• lpfc_sli3_bsg_diag_loopback_mode(9)
• lpfc_sli4_bsg_set_link_diag_state(9)
• lpfc_sli4_bsg_set_loopback_mode(9)
• lpfc_sli4_diag_fcport_reg_setup(9)
• lpfc_sli4_bsg_diag_loopback_mode(9)
• lpfc_bsg_diag_loopback_mode(9)
• lpfc_sli4_bsg_diag_mode_end(9)
• lpfc_sli4_bsg_link_diag_test(9)
• lpfcdiag_loop_self_reg(9)
• lpfcdiag_loop_self_unreg(9)
• lpfcdiag_loop_get_xri(9)
• lpfc_bsg_dma_page_alloc(9)
• lpfc_bsg_dma_page_free(9)
• lpfc_bsg_dma_page_list_free(9)
• diag_cmd_data_alloc(9)
• lpfcdiag_sli3_loop_post_rxbufs(9)
• lpfc_bsg_get_dfc_rev(9)
• lpfc_bsg_issue_mbox_cmpl(9)
• lpfc_bsg_check_cmd_access(9)
• lpfc_bsg_mbox_ext_session_reset(9)
• lpfc_rd_obj_emb0_handle_job(9)
• lpfc_bsg_issue_mbox_ext_handle_job(9)
• lpfc_bsg_issue_read_mbox_ext_cmpl(9)
• lpfc_bsg_issue_write_mbox_ext_cmpl(9)
• lpfc_bsg_sli_cfg_read_cmd_ext(9)
• lpfc_bsg_sli_cfg_write_cmd_ext(9)
• lpfc_bsg_handle_sli_cfg_mbox(9)
• lpfc_bsg_mbox_ext_abort(9)
• lpfc_bsg_read_ebuf_get(9)
• lpfc_bsg_write_ebuf_set(9)
• lpfc_bsg_handle_sli_cfg_ebuf(9)
• lpfc_bsg_handle_sli_cfg_ext(9)
• lpfc_bsg_issue_mbox(9)
• lpfc_bsg_mbox_cmd(9)
• lpfc_check_fwlog_support(9)
• lpfc_bsg_get_ras_config(9)
• lpfc_bsg_set_ras_config(9)
• lpfc_bsg_get_ras_lwpd(9)
• lpfc_bsg_get_ras_fwlog(9)
• lpfc_bsg_hst_vendor(9)
• lpfc_bsg_request(9)
• lpfc_bsg_timeout(9)

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and that's the page, bestie!! 💖✨🎀🦋🌸💅

this little love letter lives in ./drivers/scsi/lpfc and it's dated October 2026 — yes, from the future, we stay ahead of the trend 😌💜 lowkey obsessed with whoever wrote this, ngl. byeee 🫶🍓