Re: [PATCH v2 10/17] powerpc/mm: Merge vsid calculation in hash_page() and copro_data_segment()

Aneesh Kumar K.V
2014-10-01T09:55:58Z

Michael Neuling <mikey@neuling.org> writes:

> From: Ian Munsie <imunsie@au1.ibm.com>
>
> The vsid calculation between hash_page() and copro_data_segment() are very
> similar. This merges these two different versions.
>
> Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
> Signed-off-by: Michael Neuling <mikey@neuling.org>
> ---
> arch/powerpc/include/asm/mmu-hash64.h | 2 ++
> arch/powerpc/mm/copro_fault.c | 45 ++++++--------------------
> arch/powerpc/mm/hash_utils_64.c | 61 ++++++++++++++++++++++-------------
> 3 files changed, 50 insertions(+), 58 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/mmu-hash64.h b/arch/powerpc/include/asm/mmu-hash64.h
> index f84e5a5..bf43fb0 100644
> --- a/arch/powerpc/include/asm/mmu-hash64.h
> +++ b/arch/powerpc/include/asm/mmu-hash64.h
> @@ -322,6 +322,8 @@ extern int __hash_page_64K(unsigned long ea, unsigned long access,
> unsigned int local, int ssize);
> struct mm_struct;
> unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap);
> +int calculate_vsid(struct mm_struct *mm, u64 ea,
> + u64 *vsid, int *psize, int *ssize);
> extern int hash_page_mm(struct mm_struct *mm, unsigned long ea, unsigned long access, unsigned long trap);
> extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap);
> int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
> diff --git a/arch/powerpc/mm/copro_fault.c b/arch/powerpc/mm/copro_fault.c
> index 939abdf..ba8bf8e 100644
> --- a/arch/powerpc/mm/copro_fault.c
> +++ b/arch/powerpc/mm/copro_fault.c
> @@ -94,45 +94,18 @@ EXPORT_SYMBOL_GPL(copro_handle_mm_fault);
>
> int copro_data_segment(struct mm_struct *mm, u64 ea, u64 *esid, u64 *vsid)
> {
> - int psize, ssize;
> + int psize, ssize, rc;
>
> *esid = (ea & ESID_MASK) | SLB_ESID_V;
>
> - switch (REGION_ID(ea)) {
> - case USER_REGION_ID:
> - pr_devel("copro_data_segment: 0x%llx -- USER_REGION_ID\n", ea);
> -#ifdef CONFIG_PPC_MM_SLICES
> - psize = get_slice_psize(mm, ea);
> -#else
> - psize = mm->context.user_psize;
> -#endif
> - ssize = user_segment_size(ea);
> - *vsid = (get_vsid(mm->context.id, ea, ssize)
> - << slb_vsid_shift(ssize)) | SLB_VSID_USER;
> - break;
> - case VMALLOC_REGION_ID:
> - pr_devel("copro_data_segment: 0x%llx -- VMALLOC_REGION_ID\n", ea);
> - if (ea < VMALLOC_END)
> - psize = mmu_vmalloc_psize;
> - else
> - psize = mmu_io_psize;
> - ssize = mmu_kernel_ssize;
> - *vsid = (get_kernel_vsid(ea, mmu_kernel_ssize)
> - << SLB_VSID_SHIFT) | SLB_VSID_KERNEL;
> - break;
> - case KERNEL_REGION_ID:
> - pr_devel("copro_data_segment: 0x%llx -- KERNEL_REGION_ID\n", ea);
> - psize = mmu_linear_psize;
> - ssize = mmu_kernel_ssize;
> - *vsid = (get_kernel_vsid(ea, mmu_kernel_ssize)
> - << SLB_VSID_SHIFT) | SLB_VSID_KERNEL;
> - break;
> - default:
> - /* Future: support kernel segments so that drivers can use the
> - * CoProcessors */
> - pr_debug("invalid region access at %016llx\n", ea);
> - return 1;
> - }
> + rc = calculate_vsid(mm, ea, vsid, &psize, &ssize);
> + if (rc)
> + return rc;
> + if (REGION_ID(ea) == USER_REGION_ID)
> + *vsid = (*vsid << slb_vsid_shift(ssize)) | SLB_VSID_USER;
> + else
> + *vsid = (*vsid << SLB_VSID_SHIFT) | SLB_VSID_KERNEL;
> +
> *vsid |= mmu_psize_defs[psize].sllp |
> ((ssize == MMU_SEGSIZE_1T) ? SLB_VSID_B_1T : 0);
>
> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
> index 0a5c8c0..3fa81ca 100644
> --- a/arch/powerpc/mm/hash_utils_64.c
> +++ b/arch/powerpc/mm/hash_utils_64.c
> @@ -983,6 +983,38 @@ static void check_paca_psize(unsigned long ea, struct mm_struct *mm,
> }
> }
>
> +int calculate_vsid(struct mm_struct *mm, u64 ea,
> + u64 *vsid, int *psize, int *ssize)
> +{
> + switch (REGION_ID(ea)) {
> + case USER_REGION_ID:
> + pr_devel("%s: 0x%llx -- USER_REGION_ID\n", __func__, ea);
> + *psize = get_slice_psize(mm, ea);
> + *ssize = user_segment_size(ea);
> + *vsid = get_vsid(mm->context.id, ea, *ssize);
> + return 0;
> + case VMALLOC_REGION_ID:
> + pr_devel("%s: 0x%llx -- VMALLOC_REGION_ID\n", __func__, ea);
> + if (ea < VMALLOC_END)
> + *psize = mmu_vmalloc_psize;
> + else
> + *psize = mmu_io_psize;
> + *ssize = mmu_kernel_ssize;
> + *vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
> + return 0;
> + case KERNEL_REGION_ID:
> + pr_devel("%s: 0x%llx -- KERNEL_REGION_ID\n", __func__, ea);
> + *psize = mmu_linear_psize;
> + *ssize = mmu_kernel_ssize;
> + *vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
> + return 0;
> + default:
> + pr_debug("%s: invalid region access at %016llx\n", __func__, ea);
> + return 1;
> + }
> +}
> +EXPORT_SYMBOL_GPL(calculate_vsid);
> +
> /* Result code is:
> * 0 - handled
> * 1 - normal page fault
> @@ -993,7 +1025,7 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea, unsigned long access, u
> {
> enum ctx_state prev_state = exception_enter();
> pgd_t *pgdir;
> - unsigned long vsid;
> + u64 vsid;
> pte_t *ptep;
> unsigned hugeshift;
> const struct cpumask *tmp;
> @@ -1003,35 +1035,20 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea, unsigned long access, u
> DBG_LOW("%s(ea=%016lx, access=%lx, trap=%lx\n",
> __func__, ea, access, trap);
>
> - /* Get region & vsid */
> - switch (REGION_ID(ea)) {
> - case USER_REGION_ID:
> + /* Get region */
> + if (REGION_ID(ea) == USER_REGION_ID) {
> user_region = 1;
> if (! mm) {
> DBG_LOW(" user region with no mm !\n");
> rc = 1;
> goto bail;
> }
> - psize = get_slice_psize(mm, ea);
> - ssize = user_segment_size(ea);
> - vsid = get_vsid(mm->context.id, ea, ssize);
> - break;
> - case VMALLOC_REGION_ID:
> + } else
> mm = &init_mm;
> - vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
> - if (ea < VMALLOC_END)
> - psize = mmu_vmalloc_psize;
> - else
> - psize = mmu_io_psize;
> - ssize = mmu_kernel_ssize;
> - break;
> - default:
> - /* Not a valid range
> - * Send the problem up to do_page_fault
> - */
> - rc = 1;

That part is different now. We now handle kernel_region_id in case of
hash_page. Earlier we used consider it a problem.

> + rc = calculate_vsid(mm, ea, &vsid, &psize, &ssize);
> + if (rc)
> goto bail;
> - }
> +
> DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid);
>
> /* Bad address. */
> --
> 1.9.1
>
> --
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