On 7/28/21 7:04 AM, Dan Williams wrote:
> On Wed, Jul 14, 2021 at 12:36 PM Joao Martins <[email protected]>
> 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 <[email protected]>
>> ---
>> 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
That fixup definitely needs to be moved here.
>, but might as well not leave the
> bisect breakage lying around, and the kbuild robot would gripe about
> this eventually as well.
>
Yeap. Fixed, thanks for noticing.
>
>> +}
>> +
>> +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.
>
Fixed.