ecryptfs_rea...page_segment(9)

💅 ecryptfs_rea...page_segment(9) — kernel API manual energy ✨

okay bestie, so this is a page from the Kernel API Manual (yes, the actual kernel, no cap) and it's about one very specific little function. she's niche, she's lowercase, she's ecryptfs_read_lower_page_segment. let's get into it 🫶

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🌸 NAME 🌸

ecryptfs_read_lower_page_segment — and honestly? the original NAME section just trails off into the void 😭 that's the whole name, that's the entry, we move.

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✨ SYNOPSIS ✨

int ecryptfs_read_lower_page_segment (struct folio *folio_for_ecryptfs ,
pgoff_t page_index , size_t offset_in_page , size_t size , struct inode
*ecryptfs_inode );

that's the signature, character for character, do not touch her 💅

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🎀 ARGUMENTS 🎀

• folio_for_ecryptfs — the folio that the eCryptfs data is gonna get written into. that's her home. her little apartment. 🏠
• page_index — page index in page_for_ecryptfs where the writing starts. yep, the docs say page_for_ecryptfs here — quoting it exactly, iykyk 🙈
• offset_in_page — offset in page_for_ecryptfs where the writing starts. again: exactly as written, no editing bestie, i don't make the rules ⭐
• size — how many bytes get written into page_for_ecryptfs. the byte budget. the vibe check on length 📏
• ecryptfs_inode — the eCryptfs inode. that's it, that's the whole description, she's simple and i respect it 💜

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🔥 DESCRIPTION 🔥

so what does she do, you ask? okay so:

she determines the byte offset in the file for the given page plus the offset within that page, then maps the page, and then makes the call to read the contents of page_for_ecryptfs from the lower inode. like, she does the math, she does the mapping, she makes the call. main character energy fr fr 👑

and the return value?

returns zero on success; non-zero otherwise 🍓

that's the whole contract. zero = slay, anything else = not slay.

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🦋 SEE ALSO 🦋

• Kernel file ./fs/ecryptfs/read_write.c
• ecryptfs_write_lower(9)
• ecryptfs_write_lower_page_segment(9)
• ecryptfs_write(9)
• ecryptfs_read_lower(9)

go read those too, they're the friend group 💖

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and that's the page!! brought to you by ./fs/ecryptfs, dated October 2026 — a whole future date, iconique behavior honestly 🌈✨ mwah, go read your kernel source bestie 💜🧚