Re: [PATCH v2 0/6] Open HugeTLB allocation routine for more generic use

[Oscar Salvador]

On Wed, May 06, 2026 at 08:54:36AM -0700, Ackerley Tng via B4 Relay wrote:
> Hi,
> 
> The motivation for this patch series is guest_memfd, which would like
> to use HugeTLB as a generic source of huge pages but not adopt
> HugeTLB's reservation at mmap() time.
> 
> By refactoring alloc_hugetlb_folio() and some dependent functions,
> there is now an option to allocate HugeTLB folios without providing a
> VMA. Specifically, HugeTLB allocation used to be dependent on the VMA
> to
> 
> 1. Look up reservations in the resv_map
> 2. Get mpol, stored at vma->vm_policy
> 
> This refactoring provides hugetlb_alloc_folio(), which focuses on just
> the allocation itself, and associated memory and HugeTLB charging
> (cgroups). alloc_hugetlb_folio() still handles reservations in the
> resv_map and subpools.
> 
> Regarding naming, I'm definitely open to alternative names :) I chose
> hugetlb_alloc_folio() because I'm seeing this function as a general
> allocation function that is provided by the HugeTLB subsystem (hence
> the hugetlb_ prefix). I'm intending for alloc_hugetlb_folio() to be
> later refactored as a static function for use just by HugeTLB, and
> HugeTLBfs should probably use hugetlb_alloc_folio() directly.
> 
> To see how hugetlb_alloc_folio() is used by guest_memfd, the most
> recent patch series that uses this more generic HugeTLB allocation
> routine is at [1], and a newer revision of that patch series is at
> [2].

Would that be

https://lore.kernel.org/all/cover.1747264138.git.ackerleytng@xxxxxxxxxx/T/#me2152fa2cc79d651ecea7a2bce8b57725fb57465

?


-- 
Oscar Salvador
SUSE Labs