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charset="UTF-8" Binbin Wu writes: > On 5/15/2025 7:42 AM, Ackerley Tng wrote: > [...] >> >> list_for_each_entry(gmem, gmem_list, entry) >> kvm_gmem_invalidate_end(gmem, start, end); >> @@ -776,6 +879,16 @@ static long kvm_gmem_allocate(struct inode *inode, loff_t offset, loff_t len) >> >> start = offset >> PAGE_SHIFT; >> end = (offset + len) >> PAGE_SHIFT; >> + if (kvm_gmem_has_custom_allocator(inode)) { >> + size_t nr_pages; >> + void *p; >> + >> + p = kvm_gmem_allocator_private(inode); >> + nr_pages = kvm_gmem_allocator_ops(inode)->nr_pages_in_folio(p); >> + >> + start = round_down(start, nr_pages); >> + end = round_down(end, nr_pages); > It's weird here. > Should the end be round_up()? > Thanks, you're right. I believe the current consensus is that fallocate() will only be permitted for offset and lengths that are aligned not only to PAGE_SIZE but to allocator page size. In a future revision I'll check for allocator page size earlier on, before this function will get called, so this rounding will probably go away. >> + } >> >> r = 0; >> for (index = start; index < end; ) { >> > [...]