base_asce_alloc(9)

🎀 base_asce_alloc(9) 🎀

okay bestie, this is the Kernel API Manual entry for base_asce_alloc. It's giving very specific kernel-mapping energy, and we're gonna get through it together 💅✨

🌸 NAME 🌸

base_asce_alloc — create kernel mapping without enhanced DAT features

🦋 SYNOPSIS 🦋

unsigned long base_asce_alloc (unsigned long addr , unsigned long
       num_pages );

💖 ARGUMENTS 💖

• addr — virtual start address of kernel mapping
• num_pages — number of consecutive pages

✨ DESCRIPTION ✨

So base_asce_alloc generates an asce, including all required region, segment and page tables, that can be used to access the virtual kernel mapping. The difference? The returned asce does not make use of any enhanced DAT features like e.g. large pages. This is required for some I/O functions that pass an asce, like e.g. some service call requests. No cap, that's the assignment 🫶

⚠️ NOTE ⚠️

Bestie, be so fr: the returned asce may NEVER be attached to any cpu. It may only be used for I/O requests. tlb entries that might result because the asce was attached to a cpu won't be cleared. That is not a vibe — do not do it 😭🔥

🔥 SEE ALSO 🔥

• Kernel file ./arch/s390/mm/pgalloc.c
• base_asce_free(9)

mwah 💋 — footer tea: this page comes from ./arch/s390/mm, dated October 2026. That's the whole sign-off, bestie 🎀🦋