hugetlb: add documentation for vma_kernel_pagesize()

This is an exported symbol, so it should have kernel-doc.  Update it to
mention folios, and point out that they might be larger than the supported
page size for this VMA.

Link: https://lkml.kernel.org/r/20230822172459.4190699-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2023-08-22 18:24:59 +01:00 committed by Andrew Morton
parent 61ff748b5b
commit 8cfd014efd

View File

@ -968,9 +968,14 @@ pgoff_t linear_hugepage_index(struct vm_area_struct *vma,
}
EXPORT_SYMBOL_GPL(linear_hugepage_index);
/*
* Return the size of the pages allocated when backing a VMA. In the majority
* cases this will be same size as used by the page table entries.
/**
* vma_kernel_pagesize - Page size granularity for this VMA.
* @vma: The user mapping.
*
* Folios in this VMA will be aligned to, and at least the size of the
* number of bytes returned by this function.
*
* Return: The default size of the folios allocated when backing a VMA.
*/
unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
{