try_write_vid_and_data(9)

📦 version 7.3.1, in nixpkgs unstable

🦋 try_write_vid_and_data(9) — the kernel API page, but make it make sense 🦋

okay so this is a page from the Kernel API Manual, and the function we're stanning today is try_write_vid_and_data. bestie, it's giving "one last shot at writing this thing to a fresh block," and honestly? iconic. 💅

✨ NAME ✨

try_write_vid_and_data — try to write VID header and data to a new PEB.

like, try. the name said what it said and it was honest about it. 🙈

🌸 SYNOPSIS 🌸

int try_write_vid_and_data (struct ubi_volume *vol , int lnum , struct
       ubi_vid_io_buf *vidb , const void *buf , int offset , int len );

that returns an int, bestie. remember that. it comes back at the end. 👀

🎀 ARGUMENTS 🎀

  • vol — the volume description object. it's the volume we're doing all this for, main character of the whole operation fr.
  • lnum — the logical eraseblock number. yes, logical — keep that in your head, it matters later.
  • vidb — the VID buffer to write. this is the actual header payload you're handing over.
  • buf — buffer containing the data. the vibes, the contents, the whole point.
  • offset — where to start writing data. not from the top, from here. 💫
  • len — how many bytes should be written. don't skip this one, girlies, the kernel will just read past the end of your buffer and that is not the slay you think it is.

💖 DESCRIPTION 💖

so here's the tea ☕: this function tries to write the VID header and the data belonging to logical eraseblock lnum of volume vol to a new physical eraseblock.

returns zero in case of success and a negative error code in case of failure. zero = good, negative = not good, that's the whole love language of the kernel.

⚠️ and now the part where you pay attention 🙈: in case of error, it is possible that something was still written to the flash media, but may be some garbage. so like — error doesn't mean "nothing happened," it means "something maybe happened and it might be a mess." no cap. check your state, don't assume. 💀

🔥 SEE ALSO 🔥

this list is LONG, bestie, but we do not skip. every single one matters. 💜

Kernel file ./drivers/mtd/ubi/eba.c:

and that's the whole page, periodt. 🫶 this little beauty lives in ./drivers/mtd/ubi, dated October 2026, from the Kernel API Manual, and it's titled try_write_vid_and_data(9) — go forth and write your VID headers responsibly, queen 👑✨

📦 where this page comes from