ecryptfs_wr...page_segment(9)

🦋 ecryptfs_wr...page_segment(9) 🦋

okay so bestie, this one lives in the Kernel API Manual (yes, the actual kernel, no we're not joking) and the name got truncated in the header because someone at the terminal was being dramatic. It's giving "my name is too long for the tab bar" energy. 💅

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✨ NAME ✨

ecryptfs_write_lower_page_segment — and honestly? That's it. That's the whole name section. The description is literally blank, so we're just gonna sit here together and appreciate the name for a sec. 🎀

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🌸 SYNOPSIS 🌸

int ecryptfs_write_lower_page_segment (struct inode *ecryptfs_inode ,
struct folio *folio_for_lower , size_t offset_in_page , size_t size );

Look at that signature. Four arguments. int return. Iconic, no notes. 🫶

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💖 ARGUMENTS 💖

• ecryptfs_inode — the eCryptfs inode itself, like the main character of this whole operation 👑
• folio_for_lower — the folio holding the data that's about to get written down to the lower file. It's the cargo, basically 🚚
• offset_in_page — where inside folio_for_lower we start copying from. Like, don't start at zero, start here ✨
• size — how much of folio_for_lower we're actually writing to the lower file. The amount. The quantity. The vibe check on length 📏

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🔥 DESCRIPTION 🔥

So here's the whole situation, bestie: this function figures out the byte offset in the file for the given page, plus the offset within that page. Then it maps the page. Then it makes the call that writes the contents of folio_for_lower to the lower inode. That's the entire plot, and honestly it ate. 💅

Returns zero on success; non-zero otherwise. So like, 0 = slay, anything else = not slay. Remember that. 😭

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🌈 SEE ALSO 🌈

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

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fr fr that's the whole page. 🍓

signed off by that one directory, ./fs/ecryptfs, dated October 2026, from the Kernel API Manual itself — mwah, drink water, read your kernel source 💜🧚