On Wed, Jul 14, 2021 at 12:36 PM Joao Martins <joao.m.martins@xxxxxxxxxx> wrote:
>
> In preparation for describing a memmap with compound pages, move the
> actual pte population logic into a separate function
> vmemmap_populate_address() and have vmemmap_populate_basepages() walk
> through all base pages it needs to populate.
>
> Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
> ---
> mm/sparse-vmemmap.c | 44 ++++++++++++++++++++++++++------------------
> 1 file changed, 26 insertions(+), 18 deletions(-)
>
> diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
> index 80d3ba30d345..76f4158f6301 100644
> --- a/mm/sparse-vmemmap.c
> +++ b/mm/sparse-vmemmap.c
> @@ -570,33 +570,41 @@ pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
> return pgd;
> }
>
> -int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end,
> - int node, struct vmem_altmap *altmap)
> +static int __meminit vmemmap_populate_address(unsigned long addr, int node,
> + struct vmem_altmap *altmap)
> {
> - unsigned long addr = start;
> pgd_t *pgd;
> p4d_t *p4d;
> pud_t *pud;
> pmd_t *pmd;
> pte_t *pte;
>
> + pgd = vmemmap_pgd_populate(addr, node);
> + if (!pgd)
> + return -ENOMEM;
> + p4d = vmemmap_p4d_populate(pgd, addr, node);
> + if (!p4d)
> + return -ENOMEM;
> + pud = vmemmap_pud_populate(p4d, addr, node);
> + if (!pud)
> + return -ENOMEM;
> + pmd = vmemmap_pmd_populate(pud, addr, node);
> + if (!pmd)
> + return -ENOMEM;
> + pte = vmemmap_pte_populate(pmd, addr, node, altmap);
> + if (!pte)
> + return -ENOMEM;
> + vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
Missing a return here:
mm/sparse-vmemmap.c:598:1: error: control reaches end of non-void
function [-Werror=return-type]
Yes, it's fixed up in a later patch, but might as well not leave the
bisect breakage lying around, and the kbuild robot would gripe about
this eventually as well.
> +}
> +
> +int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end,
> + int node, struct vmem_altmap *altmap)
> +{
> + unsigned long addr = start;
> +
> for (; addr < end; addr += PAGE_SIZE) {
> - pgd = vmemmap_pgd_populate(addr, node);
> - if (!pgd)
> - return -ENOMEM;
> - p4d = vmemmap_p4d_populate(pgd, addr, node);
> - if (!p4d)
> - return -ENOMEM;
> - pud = vmemmap_pud_populate(p4d, addr, node);
> - if (!pud)
> - return -ENOMEM;
> - pmd = vmemmap_pmd_populate(pud, addr, node);
> - if (!pmd)
> - return -ENOMEM;
> - pte = vmemmap_pte_populate(pmd, addr, node, altmap);
> - if (!pte)
> + if (vmemmap_populate_address(addr, node, altmap))
> return -ENOMEM;
I'd prefer:
rc = vmemmap_populate_address(addr, node, altmap);
if (rc)
return rc;
...in case future refactoring adds different error codes to pass up.
> - vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
> }
>
> return 0;
> --
> 2.17.1
>
