lpfc_debugfs_read(9)

📦 version 7.3.1, in nixpkgs unstable

💅 lpfc_debugfs_read(9) — the kernel API manual, but make it make sense

okay so bestie, welcome to lpfc_debugfs_read(9) — yes that's the manual page name, it's not that deep, it's literally just the title of this whole thing 💖 this is a Kernel API Manual entry and we're gonna read it together like it's the group chat, except the group chat is a debugfs file. slay.

✨ NAME ✨

lpfc_debugfs_read — bestie. it reads a debugfs file. that's the whole vibe. 🎀

🦋 SYNOPSIS 🦋

ssize_t lpfc_debugfs_read (struct file *file , char __user *buf , size_t
nbytes , loff_t *ppos );

look at her. iconic signature. not one wasted character. 👑

🌸 ARGUMENTS 🌸

  • file — the file pointer you're reading from. she's the main character, everybody else is just supporting cast.
  • buf — the buffer where the data gets copied to. it's giving "empty cup, ready to be filled" 🫶
  • nbytes — how many bytes you wanna read. the limit. the cap. the "no more than this" energy.
  • ppos — the position in the file where the reading starts. like a bookmark but for bytes 📖✨

💜 DESCRIPTION 💜

so this routine reads data from the buffer that's indicated in the private_data field of file. yes, that private_data field. it's giving "the real data was hiding in the file struct the whole time" 💀

it starts reading at ppos, and copies up to nbytes of data to buf. that's it. that's the routine. lowkey elegant, highkey essential. ✨

🔥 RETURN 🔥

this function returns the amount of data that was read — and heads up bestie, that could be less than nbytes if the end of the file was reached, no cap 😭 — or a negative error value. so like, check your return values, fr fr. 🙈

👑 SEE ALSO 👑

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

and the whole extended friend group, in the order the original lists them, because we do not reorder the squad:

lpfc_debugfs_disc_trc_data(9), lpfc_debugfs_slow_ring_trc_data(9), lpfc_debugfs_hbqinfo_data(9), lpfc_debugfs_commonxripools_data(9), lpfc_debugfs_multixripools_data(9), lpfc_debugfs_lockstat_data(9), lpfc_debugfs_dumpHBASlim_data(9), lpfc_debugfs_dumpHostSlim_data(9), lpfc_debugfs_nodelist_data(9), lpfc_debugfs_nvmestat_data(9), lpfc_debugfs_scsistat_data(9), lpfc_debugfs_ioktime_data(9), lpfc_debugfs_nvmeio_trc_data(9), lpfc_debugfs_hdwqstat_data(9), lpfc_debugfs_disc_trc(9), lpfc_debugfs_slow_ring_trc(9), lpfc_debugfs_nvme_trc(9), lpfc_debugfs_disc_trc_open(9), lpfc_debugfs_slow_ring_trc_open(9), lpfc_debugfs_hbqinfo_open(9), lpfc_debugfs_multixripools_open(9), lpfc_debugfs_lockstat_open(9), lpfc_debugfs_ras_log_open(9), lpfc_debugfs_dumpHBASlim_open(9), lpfc_debugfs_dumpHostSlim_open(9), lpfc_debugfs_nodelist_open(9), lpfc_debugfs_lseek(9), lpfc_debugfs_release(9), lpfc_debugfs_multixripools_write(9), lpfc_idiag_cmd_get(9), lpfc_idiag_open(9), lpfc_idiag_release(9), lpfc_idiag_cmd_release(9), lpfc_idiag_pcicfg_read(9), lpfc_idiag_pcicfg_write(9), lpfc_idiag_baracc_read(9), lpfc_idiag_baracc_write(9), lpfc_idiag_queinfo_read(9), lpfc_idiag_que_param_check(9), lpfc_idiag_queacc_read_qe(9), lpfc_idiag_queacc_read(9), lpfc_idiag_queacc_write(9), lpfc_idiag_drbacc_read_reg(9), lpfc_idiag_drbacc_read(9), lpfc_idiag_drbacc_write(9), lpfc_idiag_ctlacc_read_reg(9), lpfc_idiag_ctlacc_read(9), lpfc_idiag_ctlacc_write(9), lpfc_idiag_mbxacc_get_setup(9), lpfc_idiag_mbxacc_read(9), lpfc_idiag_mbxacc_write(9), lpfc_idiag_extacc_avail_get(9), lpfc_idiag_extacc_alloc_get(9), lpfc_idiag_extacc_drivr_get(9), lpfc_idiag_extacc_write(9), lpfc_idiag_extacc_read(9), lpfc_debugfs_initialize(9), lpfc_debugfs_terminate(9), lpfc_debug_dump_all_queues(9)

okay that's the whole page 💖 go read your debugfs file, bestie, you got this 🫶✨

and that's a wrap on lpfc_debugfs_read(9), from the ./drivers/scsi/lpfc source, dated October 2026 — periodt, no notes, see u in the next manpage 🌈💅🍓

📦 where this page comes from