Messages in this thread | | | Subject | Re: [PATCH v2 2/4] ioremap: Implement TLB_INV before huge mapping | From | Chintan Pandya <> | Date | Thu, 15 Mar 2018 19:49:01 +0530 |
| |
On 3/15/2018 7:01 PM, Mark Rutland wrote: > On Thu, Mar 15, 2018 at 06:15:04PM +0530, Chintan Pandya wrote: >> @@ -91,10 +93,15 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr, >> >> if (ioremap_pmd_enabled() && >> ((next - addr) == PMD_SIZE) && >> - IS_ALIGNED(phys_addr + addr, PMD_SIZE) && >> - pmd_free_pte_page(pmd)) { >> - if (pmd_set_huge(pmd, phys_addr + addr, prot)) >> + IS_ALIGNED(phys_addr + addr, PMD_SIZE)) { >> + old_pmd = *pmd; >> + pmd_clear(pmd); >> + flush_tlb_pgtable(&init_mm, addr); >> + if (pmd_set_huge(pmd, phys_addr + addr, prot)) { >> + pmd_free_pte_page(&old_pmd); >> continue; >> + } else >> + set_pmd(pmd, old_pmd); >> } >> > > Can we have something like a pmd_can_set_huge() helper? Then we could > avoid pointless modification and TLB invalidation work when > pmd_set_huge() will fail.
Actually, pmd_set_huge() will never fail because, if CONFIG_HAVE_ARCH_HUGE_VMAP is disabled, ioremap_pmd_enabled() will fail and if enabled (i.e. ARM64 & x86), they don't fail in their implementation. So, rather we can do the following.
- if (pmd_set_huge(pmd, phys_addr + addr, prot)) { - pmd_free_pte_page(&old_pmd); - continue; - } else - set_pmd(pmd, old_pmd); + pmd_set_huge(pmd, phys_addr + addr, prot) + pmd_free_pte_page(&old_pmd); + continue;
> > if (ioremap_pmd_enabled() && > ((next - addr) == PMD_SIZE) && > IS_ALIGNED(phys_addr + addr, PMD_SIZE) && > pmd_can_set_huge(pmd, phys_addr + addr, prot)) { > // clear entries, invalidate TLBs, and free tables > ... > continue; > > } > > Thanks, > MArk. > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
Chintan -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
| |