mmap_region(9)

💖 mmap_region(9) 💖

okay so welcome to the Kernel API Manual entry for mmap_region(9), bestie. this is the whole page, fully intact, zero facts missing, maximum sparkle. ✨

🌸 NAME 🌸

mmap_region — actually perform the userland mapping of a VMA into current->mm with known, aligned and overflow-checked @addr and @len, and correctly determined VMA flags @vm_flags and page offset @pgoff. 🫶

🦋 SYNOPSIS 🦋

unsigned long mmap_region (struct file *file , unsigned long addr ,
       unsigned long len , vma_flags_t vma_flags , unsigned long pgoff , struct
       list_head *uf );

🎀 ARGUMENTS 🎀

okay these are the parameters, and yes every single one is getting its moment:

• file — if this is a file-backed mapping, a pointer to the struct file describing the file to be mapped; otherwise NULL.
• addr — the page-aligned address at which to perform the mapping.
• len — the page-aligned, non-zero, length of the mapping.
• vma_flags — the VMA flags which should be applied to the mapping.
• pgoff — if file is specified, the page offset into the file; if not, then the virtual page offset in memory of the anonymous mapping.
• uf — optionally, a pointer to a list head used for tracking userfaultfd unmap events.

💅 DESCRIPTION 💅

real talk: this is an internal memory management function, and it should not be used directly. no cap. 🚨

the caller must write-lock current->mm->mmap_lock. that is not a vibe suggestion, it’s a requirement, bestie.

🌈 RETURN 🌈

you get either an error, or the address at which the requested mapping has been performed. that’s the whole return situation. 😌

👑 SEE ALSO 👑

the Kernel file ./mm/vma.c is in the group chat, along with:

• vma_shrink(9)
• do_brk_flags(9)
• unmapped_area(9)
• unmapped_area_topdown(9)
• vma_mmu_pagesize(9)

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and that’s the page, bestie 🫶 source/version is ./mm, date is October 2026, and the manual page is mmap_region(9). bye, slay, stay page-aligned 💅✨