powerpc/mm: flatten function __find_linux_pte() step 1

__find_linux_pte() is full of if/else which is hard to
follow allthough the handling is pretty simple.

This patch flattens the function by getting rid of as much if/else
as possible. In order to ease the review, this is done in three steps.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Christophe Leroy 2019-04-26 05:59:51 +00:00 committed by Michael Ellerman
parent 4df4b27585
commit fab9a1165b

View file

@ -339,12 +339,16 @@ pte_t *__find_linux_pte(pgd_t *pgdir, unsigned long ea,
*/ */
if (pgd_none(pgd)) if (pgd_none(pgd))
return NULL; return NULL;
else if (pgd_huge(pgd)) {
ret_pte = (pte_t *) pgdp; if (pgd_huge(pgd)) {
ret_pte = (pte_t *)pgdp;
goto out; goto out;
} else if (is_hugepd(__hugepd(pgd_val(pgd)))) }
if (is_hugepd(__hugepd(pgd_val(pgd)))) {
hpdp = (hugepd_t *)&pgd; hpdp = (hugepd_t *)&pgd;
else { goto out_huge;
}
{
/* /*
* Even if we end up with an unmap, the pgtable will not * Even if we end up with an unmap, the pgtable will not
* be freed, because we do an rcu free and here we are * be freed, because we do an rcu free and here we are
@ -356,12 +360,16 @@ pte_t *__find_linux_pte(pgd_t *pgdir, unsigned long ea,
if (pud_none(pud)) if (pud_none(pud))
return NULL; return NULL;
else if (pud_huge(pud)) {
if (pud_huge(pud)) {
ret_pte = (pte_t *) pudp; ret_pte = (pte_t *) pudp;
goto out; goto out;
} else if (is_hugepd(__hugepd(pud_val(pud)))) }
if (is_hugepd(__hugepd(pud_val(pud)))) {
hpdp = (hugepd_t *)&pud; hpdp = (hugepd_t *)&pud;
else { goto out_huge;
}
{
pdshift = PMD_SHIFT; pdshift = PMD_SHIFT;
pmdp = pmd_offset(&pud, ea); pmdp = pmd_offset(&pud, ea);
pmd = READ_ONCE(*pmdp); pmd = READ_ONCE(*pmdp);
@ -386,12 +394,16 @@ pte_t *__find_linux_pte(pgd_t *pgdir, unsigned long ea,
if (pmd_huge(pmd) || pmd_large(pmd)) { if (pmd_huge(pmd) || pmd_large(pmd)) {
ret_pte = (pte_t *) pmdp; ret_pte = (pte_t *) pmdp;
goto out; goto out;
} else if (is_hugepd(__hugepd(pmd_val(pmd)))) }
if (is_hugepd(__hugepd(pmd_val(pmd)))) {
hpdp = (hugepd_t *)&pmd; hpdp = (hugepd_t *)&pmd;
else goto out_huge;
return pte_offset_kernel(&pmd, ea); }
return pte_offset_kernel(&pmd, ea);
} }
} }
out_huge:
if (!hpdp) if (!hpdp)
return NULL; return NULL;