| Message ID | 71017345495dadf0cb96839d261ffeb904dbfef8.1715971869.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Reimplement huge pages without hugepd on powerpc (8xx, e500, book3s/64) | expand |
On Fri, May 17, 2024 at 09:00:01PM +0200, Christophe Leroy wrote: > In order to fit better with standard Linux page tables layout, add > support for 8M pages using contiguous PTE entries in a standard > page table. Page tables will then be populated with 1024 similar > entries and two PMD entries will point to that page table. > > The PMD entries also get a flag to tell it is addressing an 8M page, > this is required for the HW tablewalk assistance. > > Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> I guess that this will slightly change if you remove patch#1 and patch#2 as you said you will. So I will not comment on the overall design because I do not know how it will look afterwards, but just some things that caught my eye > --- a/arch/powerpc/include/asm/hugetlb.h > +++ b/arch/powerpc/include/asm/hugetlb.h > @@ -41,7 +41,16 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr, > static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm, > unsigned long addr, pte_t *ptep) > { > - return __pte(pte_update(mm, addr, ptep, ~0UL, 0, 1)); > + pmd_t *pmdp = (pmd_t *)ptep; > + pte_t pte; > + > + if (IS_ENABLED(CONFIG_PPC_8xx) && pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { There are quite some places where you do the "pmd_off" to check whether that is a 8MB entry. I think it would make somse sense to have some kind of macro/function to make more clear what we are checking against. e.g: #define pmd_is_SZ_8M(mm, addr, pmdp) (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) (or whatever name you see fit) then you would just need if (IS_ENABLED(CONFIG_PPC_8xx && pmd_is_SZ_8M(mm, addr, pdmp)) Because I see that is also scaterred in 8xx code. > + pte = __pte(pte_update(mm, addr, pte_offset_kernel(pmdp, 0), ~0UL, 0, 1)); > + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), ~0UL, 0, 1); I have this fresh one because I recently read about 8xx pagetables, but not sure how my memory will survive this, so maybe throw a little comment in there that we are pointing the two pmds to the area. Also, the way we pass the parameters here to pte_update() is a bit awkward. Ideally we should be using some meaningful names? clr_all_bits = ~0UL set_bits = 0 bool is_huge = true pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), clr_all_bits, set_bits, is_huge) or something along those lines > -static inline int check_and_get_huge_psize(int shift) > -{ > - return shift_to_mmu_psize(shift); > + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) Here you could also use the pmd_is_SZ_8M() > + ptep = pte_offset_kernel(pmdp, 0); > + return ptep_get(ptep); > } > > #define __HAVE_ARCH_HUGE_SET_HUGE_PTE_AT > @@ -53,7 +33,14 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, > static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr, > pte_t *ptep, unsigned long sz) > { > - pte_update(mm, addr, ptep, ~0UL, 0, 1); > + pmd_t *pmdp = (pmd_t *)ptep; > + > + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { > + pte_update(mm, addr, pte_offset_kernel(pmdp, 0), ~0UL, 0, 1); > + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), ~0UL, 0, 1); > + } else { > + pte_update(mm, addr, ptep, ~0UL, 0, 1); > + } Could we not leverage this in huge_ptep_get_and_clear()? AFAICS, huge_pet_get_and_clear(mm, addr, pte_t *p) { pte_t pte = pte_val(*p); huge_pte_clear(mm, addr, p); return pte; } Or maybe it is not that easy if different powerpc platforms provide their own. It might be worth checking though. > } > > #define __HAVE_ARCH_HUGE_PTEP_SET_WRPROTECT > @@ -63,7 +50,14 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, > unsigned long clr = ~pte_val(pte_wrprotect(__pte(~0))); > unsigned long set = pte_val(pte_wrprotect(__pte(0))); > > - pte_update(mm, addr, ptep, clr, set, 1); > + pmd_t *pmdp = (pmd_t *)ptep; > + > + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { > + pte_update(mm, addr, pte_offset_kernel(pmdp, 0), clr, set, 1); > + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), clr, set, 1); > + } else { > + pte_update(mm, addr, ptep, clr, set, 1); I would replace the "1" with "is_huge" or "huge", as being done in __ptep_set_access_flags , something that makes it more clear without the need to check pte_update(). > #endif /* _ASM_POWERPC_PGALLOC_32_H */ > diff --git a/arch/powerpc/include/asm/nohash/32/pte-8xx.h b/arch/powerpc/include/asm/nohash/32/pte-8xx.h > index 07df6b664861..b05cc4f87713 100644 > --- a/arch/powerpc/include/asm/nohash/32/pte-8xx.h > +++ b/arch/powerpc/include/asm/nohash/32/pte-8xx.h ... > - * For other page sizes, we have a single entry in the table. > + * For 8M pages, we have 1024 entries as if it was > + * 4M pages, but they are flagged as 8M pages for the hardware. Maybe drop a comment that a single PMD entry is worth 4MB, so > + * For 4k pages, we have a single entry in the table. > */ > -static pmd_t *pmd_off(struct mm_struct *mm, unsigned long addr); > -static int hugepd_ok(hugepd_t hpd); > - > static inline int number_of_cells_per_pte(pmd_t *pmd, pte_basic_t val, int huge) > { > if (!huge) > return PAGE_SIZE / SZ_4K; > - else if (hugepd_ok(*((hugepd_t *)pmd))) > - return 1; > + else if ((pmd_val(*pmd) & _PMD_PAGE_MASK) == _PMD_PAGE_8M) > + return SZ_4M / SZ_4K; this becomes more intuitive. > +static inline void pmd_populate_kernel_size(struct mm_struct *mm, pmd_t *pmdp, > + pte_t *pte, unsigned long sz) > +{ > + if (sz == SZ_8M) > + *pmdp = __pmd(__pa(pte) | _PMD_PRESENT | _PMD_PAGE_8M); > + else > + *pmdp = __pmd(__pa(pte) | _PMD_PRESENT); > +} > + > +static inline void pmd_populate_size(struct mm_struct *mm, pmd_t *pmdp, > + pgtable_t pte_page, unsigned long sz) > +{ > + if (sz == SZ_8M) > + *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT | _PMD_PAGE_8M); > + else > + *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT); > +} In patch#1 you mentioned this will change with the removal of patch#1 and patch#2. > --- a/arch/powerpc/mm/hugetlbpage.c > +++ b/arch/powerpc/mm/hugetlbpage.c > @@ -183,9 +183,6 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, > if (!hpdp) > return NULL; > > - if (IS_ENABLED(CONFIG_PPC_8xx) && pshift < PMD_SHIFT) > - return pte_alloc_huge(mm, (pmd_t *)hpdp, addr, sz); > - > BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp)); > > if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, > @@ -198,10 +195,18 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, > pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, > unsigned long addr, unsigned long sz) > { > + pmd_t *pmd = pmd_off(mm, addr); > + > if (sz < PMD_SIZE) > - return pte_alloc_huge(mm, pmd_off(mm, addr), addr, sz); > + return pte_alloc_huge(mm, pmd, addr, sz); > > - return NULL; > + if (sz != SZ_8M) > + return NULL; > + if (!pte_alloc_huge(mm, pmd, addr, sz)) > + return NULL; > + if (!pte_alloc_huge(mm, pmd + 1, addr, sz)) > + return NULL; > + return (pte_t *)pmd; I think that having the check for invalid huge page sizes upfront would make more sense, maybe just a matter of taste. /* Unsupported size */ if (sz > PMD_SIZE && sz = SZ_8M) return NULL; if (sz < PMD_SIZE) ... /* 8MB huge pages */ ... return (pte_t *) pmd; Also, I am not a big fan of the two separate pte_alloc_huge() for pmd#0+pmd#1, and I am thinking we might want to hide that within a function and drop a comment in there explaining why we are updatng both pmds. > diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c > index d93433e26ded..99f656b3f9f3 100644 > --- a/arch/powerpc/mm/nohash/8xx.c > +++ b/arch/powerpc/mm/nohash/8xx.c > @@ -48,20 +48,6 @@ unsigned long p_block_mapped(phys_addr_t pa) > return 0; > } > > -static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va) > -{ > - if (hpd_val(*pmdp) == 0) { > - pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K); > - > - if (!ptep) > - return NULL; > - > - hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M); > - hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M); > - } > - return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); > -} > - > static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa, > pgprot_t prot, int psize, bool new) Am I blind or do we never use the 'new' parameter? I checked the tree and it seems we always pass it 'true'. arch/powerpc/mm/nohash/8xx.c: err = __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new); arch/powerpc/mm/nohash/8xx.c: err = __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_8M, new); arch/powerpc/mm/nohash/8xx.c: err = __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new); arch/powerpc/mm/nohash/8xx.c: __early_map_kernel_hugepage(VIRT_IMMR_BASE, PHYS_IMMR_BASE, PAGE_KERNEL_NCG, MMU_PAGE_512K, true); I think we can drop the 'new' and the block code that tries to handle it? > diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c > index acdf64c9b93e..59f0d7706d2f 100644 > --- a/arch/powerpc/mm/pgtable.c > +++ b/arch/powerpc/mm/pgtable.c > +void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, > + pte_t pte, unsigned long sz) > +{ > + pmd_t *pmdp = pmd_off(mm, addr); > + > + pte = set_pte_filter(pte, addr); > + > + if (sz == SZ_8M) { > + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp, 0), pte_val(pte)); > + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp + 1, 0), pte_val(pte) + SZ_4M); You also mentioned that this would slightly change after you drop patch#0 and patch#1. The only comment I have right know would be to add a little comment explaining the layout (the replication of 1024 entries), or just something like "see comment from number_of_cells_per_pte".
Le 24/05/2024 à 12:02, Oscar Salvador a écrit : > On Fri, May 17, 2024 at 09:00:01PM +0200, Christophe Leroy wrote: >> In order to fit better with standard Linux page tables layout, add >> support for 8M pages using contiguous PTE entries in a standard >> page table. Page tables will then be populated with 1024 similar >> entries and two PMD entries will point to that page table. >> >> The PMD entries also get a flag to tell it is addressing an 8M page, >> this is required for the HW tablewalk assistance. >> >> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> > > I guess that this will slightly change if you remove patch#1 and patch#2 > as you said you will. > So I will not comment on the overall design because I do not know how it will > look afterwards, but just some things that caught my eye Sure. I should send-out a v3 today or tomorrow, once I've done a few more tests. > >> --- a/arch/powerpc/include/asm/hugetlb.h >> +++ b/arch/powerpc/include/asm/hugetlb.h >> @@ -41,7 +41,16 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr, >> static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm, >> unsigned long addr, pte_t *ptep) >> { >> - return __pte(pte_update(mm, addr, ptep, ~0UL, 0, 1)); >> + pmd_t *pmdp = (pmd_t *)ptep; >> + pte_t pte; >> + >> + if (IS_ENABLED(CONFIG_PPC_8xx) && pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { > > There are quite some places where you do the "pmd_off" to check whether that > is a 8MB entry. I refactored the code, now I have only two places with it: pte_update() and huge_ptep_get() By the way it doesn't check that PMD is 8M, it checks that the ptep points to the first PMD entry matching the said address. > I think it would make somse sense to have some kind of macro/function to make > more clear what we are checking against. > e.g: > > #define pmd_is_SZ_8M(mm, addr, pmdp) (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) > (or whatever name you see fit) > > then you would just need > > if (IS_ENABLED(CONFIG_PPC_8xx && pmd_is_SZ_8M(mm, addr, pdmp)) > > Because I see that is also scaterred in 8xx code. > > >> + pte = __pte(pte_update(mm, addr, pte_offset_kernel(pmdp, 0), ~0UL, 0, 1)); >> + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), ~0UL, 0, 1); > > I have this fresh one because I recently read about 8xx pagetables, but not sure > how my memory will survive this, so maybe throw a little comment in there that > we are pointing the two pmds to the area. The two PMD are now pointing to there own areas, we are not anymore in the hugepd case where the PMD was pointing to a single HUGEPD containing a single HUGEPTE. > > Also, the way we pass the parameters here to pte_update() is a bit awkward. > Ideally we should be using some meaningful names? > > clr_all_bits = ~0UL > set_bits = 0 > bool is_huge = true > > pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), clr_all_bits, set_bits, is_huge) > > or something along those lines Well, with my refactoring those functions are not modified anymore so I won't change them. > >> -static inline int check_and_get_huge_psize(int shift) >> -{ >> - return shift_to_mmu_psize(shift); >> + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) > > Here you could also use the pmd_is_SZ_8M() Yes, may do that. > >> + ptep = pte_offset_kernel(pmdp, 0); >> + return ptep_get(ptep); >> } >> >> #define __HAVE_ARCH_HUGE_SET_HUGE_PTE_AT >> @@ -53,7 +33,14 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, >> static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr, >> pte_t *ptep, unsigned long sz) >> { >> - pte_update(mm, addr, ptep, ~0UL, 0, 1); >> + pmd_t *pmdp = (pmd_t *)ptep; >> + >> + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { >> + pte_update(mm, addr, pte_offset_kernel(pmdp, 0), ~0UL, 0, 1); >> + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), ~0UL, 0, 1); >> + } else { >> + pte_update(mm, addr, ptep, ~0UL, 0, 1); >> + } > > Could we not leverage this in huge_ptep_get_and_clear()? I'm not modifying that anymore > AFAICS, > > huge_pet_get_and_clear(mm, addr, pte_t *p) > { > pte_t pte = pte_val(*p); > > huge_pte_clear(mm, addr, p); > return pte; > } > > Or maybe it is not that easy if different powerpc platforms provide their own. > It might be worth checking though. > >> } >> >> #define __HAVE_ARCH_HUGE_PTEP_SET_WRPROTECT >> @@ -63,7 +50,14 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, >> unsigned long clr = ~pte_val(pte_wrprotect(__pte(~0))); >> unsigned long set = pte_val(pte_wrprotect(__pte(0))); >> >> - pte_update(mm, addr, ptep, clr, set, 1); >> + pmd_t *pmdp = (pmd_t *)ptep; >> + >> + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { >> + pte_update(mm, addr, pte_offset_kernel(pmdp, 0), clr, set, 1); >> + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), clr, set, 1); >> + } else { >> + pte_update(mm, addr, ptep, clr, set, 1); > > I would replace the "1" with "is_huge" or "huge", as being done in > __ptep_set_access_flags , something that makes it more clear without the need > to check pte_update(). It's not modified anymore > > >> #endif /* _ASM_POWERPC_PGALLOC_32_H */ >> diff --git a/arch/powerpc/include/asm/nohash/32/pte-8xx.h b/arch/powerpc/include/asm/nohash/32/pte-8xx.h >> index 07df6b664861..b05cc4f87713 100644 >> --- a/arch/powerpc/include/asm/nohash/32/pte-8xx.h >> +++ b/arch/powerpc/include/asm/nohash/32/pte-8xx.h > ... >> - * For other page sizes, we have a single entry in the table. >> + * For 8M pages, we have 1024 entries as if it was >> + * 4M pages, but they are flagged as 8M pages for the hardware. > > Maybe drop a comment that a single PMD entry is worth 4MB, so Ok, added that the 4M is indeed PMD_SIZE > >> + * For 4k pages, we have a single entry in the table. >> */ >> -static pmd_t *pmd_off(struct mm_struct *mm, unsigned long addr); >> -static int hugepd_ok(hugepd_t hpd); >> - >> static inline int number_of_cells_per_pte(pmd_t *pmd, pte_basic_t val, int huge) >> { >> if (!huge) >> return PAGE_SIZE / SZ_4K; >> - else if (hugepd_ok(*((hugepd_t *)pmd))) >> - return 1; >> + else if ((pmd_val(*pmd) & _PMD_PAGE_MASK) == _PMD_PAGE_8M) >> + return SZ_4M / SZ_4K; > > this becomes more intuitive. > > >> +static inline void pmd_populate_kernel_size(struct mm_struct *mm, pmd_t *pmdp, >> + pte_t *pte, unsigned long sz) >> +{ >> + if (sz == SZ_8M) >> + *pmdp = __pmd(__pa(pte) | _PMD_PRESENT | _PMD_PAGE_8M); >> + else >> + *pmdp = __pmd(__pa(pte) | _PMD_PRESENT); >> +} >> + >> +static inline void pmd_populate_size(struct mm_struct *mm, pmd_t *pmdp, >> + pgtable_t pte_page, unsigned long sz) >> +{ >> + if (sz == SZ_8M) >> + *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT | _PMD_PAGE_8M); >> + else >> + *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT); >> +} > > In patch#1 you mentioned this will change with the removal of patch#1 > and patch#2. Yes this goes away. > >> --- a/arch/powerpc/mm/hugetlbpage.c >> +++ b/arch/powerpc/mm/hugetlbpage.c >> @@ -183,9 +183,6 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, >> if (!hpdp) >> return NULL; >> >> - if (IS_ENABLED(CONFIG_PPC_8xx) && pshift < PMD_SHIFT) >> - return pte_alloc_huge(mm, (pmd_t *)hpdp, addr, sz); >> - >> BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp)); >> >> if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, >> @@ -198,10 +195,18 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, >> pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, >> unsigned long addr, unsigned long sz) >> { >> + pmd_t *pmd = pmd_off(mm, addr); >> + >> if (sz < PMD_SIZE) >> - return pte_alloc_huge(mm, pmd_off(mm, addr), addr, sz); >> + return pte_alloc_huge(mm, pmd, addr, sz); >> >> - return NULL; >> + if (sz != SZ_8M) >> + return NULL; >> + if (!pte_alloc_huge(mm, pmd, addr, sz)) >> + return NULL; >> + if (!pte_alloc_huge(mm, pmd + 1, addr, sz)) >> + return NULL; >> + return (pte_t *)pmd; > > I think that having the check for invalid huge page sizes upfront would > make more sense, maybe just a matter of taste. Well, it would make it less easy when we go one step further to support e500 and book3s/64. I prefer to do it that way to keep it as flat as possible and avoid a deep if ... if ... if By the way I have now squashed patch 11 into patch 5. > > /* Unsupported size */ > if (sz > PMD_SIZE && sz = SZ_8M) > return NULL; > > if (sz < PMD_SIZE) > ... > /* 8MB huge pages */ > ... > > return (pte_t *) pmd; > > Also, I am not a big fan of the two separate pte_alloc_huge() for pmd#0+pmd#1, > and I am thinking we might want to hide that within a function and drop a > comment in there explaining why we are updatng both pmds. Now changed to: + for (i = 0; i < sz / PMD_SIZE; i++) { + if (!pte_alloc_huge(mm, pmd + i, addr)) + return NULL; + } > > > >> diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c >> index d93433e26ded..99f656b3f9f3 100644 >> --- a/arch/powerpc/mm/nohash/8xx.c >> +++ b/arch/powerpc/mm/nohash/8xx.c >> @@ -48,20 +48,6 @@ unsigned long p_block_mapped(phys_addr_t pa) >> return 0; >> } >> >> -static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va) >> -{ >> - if (hpd_val(*pmdp) == 0) { >> - pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K); >> - >> - if (!ptep) >> - return NULL; >> - >> - hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M); >> - hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M); >> - } >> - return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); >> -} >> - >> static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa, >> pgprot_t prot, int psize, bool new) > > Am I blind or do we never use the 'new' parameter? > I checked the tree and it seems we always pass it 'true'. You must be blind :) $ git grep mmu_mapin_ram_chunk arch/powerpc/mm/nohash/8xx.c:static int mmu_mapin_ram_chunk(unsigned long offset, unsigned long top, arch/powerpc/mm/nohash/8xx.c: mmu_mapin_ram_chunk(0, boundary, PAGE_KERNEL_TEXT, true); arch/powerpc/mm/nohash/8xx.c: mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL_TEXT, true); arch/powerpc/mm/nohash/8xx.c: mmu_mapin_ram_chunk(einittext8, top, PAGE_KERNEL, true); arch/powerpc/mm/nohash/8xx.c: err = mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL, false); arch/powerpc/mm/nohash/8xx.c: err = mmu_mapin_ram_chunk(0, sinittext, PAGE_KERNEL_ROX, false); > > arch/powerpc/mm/nohash/8xx.c: err = __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new); > arch/powerpc/mm/nohash/8xx.c: err = __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_8M, new); > arch/powerpc/mm/nohash/8xx.c: err = __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new); > arch/powerpc/mm/nohash/8xx.c: > __early_map_kernel_hugepage(VIRT_IMMR_BASE, PHYS_IMMR_BASE, PAGE_KERNEL_NCG, MMU_PAGE_512K, true); > > I think we can drop the 'new' and the block code that tries to handle > it? > >> diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c >> index acdf64c9b93e..59f0d7706d2f 100644 >> --- a/arch/powerpc/mm/pgtable.c >> +++ b/arch/powerpc/mm/pgtable.c > >> +void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, >> + pte_t pte, unsigned long sz) >> +{ >> + pmd_t *pmdp = pmd_off(mm, addr); >> + >> + pte = set_pte_filter(pte, addr); >> + >> + if (sz == SZ_8M) { >> + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp, 0), pte_val(pte)); >> + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp + 1, 0), pte_val(pte) + SZ_4M); > > You also mentioned that this would slightly change after you drop > patch#0 and patch#1. > The only comment I have right know would be to add a little comment > explaining the layout (the replication of 1024 entries), or just > something like "see comment from number_of_cells_per_pte". > Done. Thanks for the rewiew. Christophe
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index a1a3b3363008..6a4ea7dad23f 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -135,7 +135,6 @@ config PPC select ARCH_HAS_DMA_MAP_DIRECT if PPC_PSERIES select ARCH_HAS_FORTIFY_SOURCE select ARCH_HAS_GCOV_PROFILE_ALL - select ARCH_HAS_HUGEPD if HUGETLB_PAGE select ARCH_HAS_KCOV select ARCH_HAS_MEMBARRIER_CALLBACKS select ARCH_HAS_MEMBARRIER_SYNC_CORE diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h index 79176a499763..36ed6d976cf9 100644 --- a/arch/powerpc/include/asm/hugetlb.h +++ b/arch/powerpc/include/asm/hugetlb.h @@ -41,7 +41,16 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr, static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - return __pte(pte_update(mm, addr, ptep, ~0UL, 0, 1)); + pmd_t *pmdp = (pmd_t *)ptep; + pte_t pte; + + if (IS_ENABLED(CONFIG_PPC_8xx) && pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { + pte = __pte(pte_update(mm, addr, pte_offset_kernel(pmdp, 0), ~0UL, 0, 1)); + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), ~0UL, 0, 1); + } else { + pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 1)); + } + return pte; } #define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH diff --git a/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h b/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h index 92df40c6cc6b..1414cfd28987 100644 --- a/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h @@ -4,45 +4,25 @@ #define PAGE_SHIFT_8M 23 -static inline pte_t *hugepd_page(hugepd_t hpd) -{ - BUG_ON(!hugepd_ok(hpd)); - - return (pte_t *)__va(hpd_val(hpd) & ~HUGEPD_SHIFT_MASK); -} - -static inline unsigned int hugepd_shift(hugepd_t hpd) -{ - return PAGE_SHIFT_8M; -} - -static inline pte_t *hugepte_offset(hugepd_t hpd, unsigned long addr, - unsigned int pdshift) -{ - unsigned long idx = (addr & (SZ_4M - 1)) >> PAGE_SHIFT; - - return hugepd_page(hpd) + idx; -} - static inline void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr) { flush_tlb_page(vma, vmaddr); } -static inline void hugepd_populate(hugepd_t *hpdp, pte_t *new, unsigned int pshift) +static inline int check_and_get_huge_psize(int shift) { - *hpdp = __hugepd(__pa(new) | _PMD_USER | _PMD_PRESENT | _PMD_PAGE_8M); + return shift_to_mmu_psize(shift); } -static inline void hugepd_populate_kernel(hugepd_t *hpdp, pte_t *new, unsigned int pshift) +#define __HAVE_ARCH_HUGE_PTEP_GET +static inline pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - *hpdp = __hugepd(__pa(new) | _PMD_PRESENT | _PMD_PAGE_8M); -} + pmd_t *pmdp = (pmd_t *)ptep; -static inline int check_and_get_huge_psize(int shift) -{ - return shift_to_mmu_psize(shift); + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) + ptep = pte_offset_kernel(pmdp, 0); + return ptep_get(ptep); } #define __HAVE_ARCH_HUGE_SET_HUGE_PTE_AT @@ -53,7 +33,14 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep, unsigned long sz) { - pte_update(mm, addr, ptep, ~0UL, 0, 1); + pmd_t *pmdp = (pmd_t *)ptep; + + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { + pte_update(mm, addr, pte_offset_kernel(pmdp, 0), ~0UL, 0, 1); + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), ~0UL, 0, 1); + } else { + pte_update(mm, addr, ptep, ~0UL, 0, 1); + } } #define __HAVE_ARCH_HUGE_PTEP_SET_WRPROTECT @@ -63,7 +50,14 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long clr = ~pte_val(pte_wrprotect(__pte(~0))); unsigned long set = pte_val(pte_wrprotect(__pte(0))); - pte_update(mm, addr, ptep, clr, set, 1); + pmd_t *pmdp = (pmd_t *)ptep; + + if (pmdp == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M))) { + pte_update(mm, addr, pte_offset_kernel(pmdp, 0), clr, set, 1); + pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), clr, set, 1); + } else { + pte_update(mm, addr, ptep, clr, set, 1); + } } #ifdef CONFIG_PPC_4K_PAGES diff --git a/arch/powerpc/include/asm/nohash/32/pgalloc.h b/arch/powerpc/include/asm/nohash/32/pgalloc.h index 11eac371e7e0..ff4f90cfb461 100644 --- a/arch/powerpc/include/asm/nohash/32/pgalloc.h +++ b/arch/powerpc/include/asm/nohash/32/pgalloc.h @@ -14,6 +14,7 @@ #define __pmd_free_tlb(tlb,x,a) do { } while (0) /* #define pgd_populate(mm, pmd, pte) BUG() */ +#ifndef CONFIG_PPC_8xx static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *pte) { @@ -31,5 +32,6 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp, else *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT); } +#endif #endif /* _ASM_POWERPC_PGALLOC_32_H */ diff --git a/arch/powerpc/include/asm/nohash/32/pte-8xx.h b/arch/powerpc/include/asm/nohash/32/pte-8xx.h index 07df6b664861..b05cc4f87713 100644 --- a/arch/powerpc/include/asm/nohash/32/pte-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/pte-8xx.h @@ -129,32 +129,34 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, } #define ptep_set_wrprotect ptep_set_wrprotect +static pmd_t *pmd_off(struct mm_struct *mm, unsigned long addr); +static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address); + static inline void __ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep, pte_t entry, unsigned long address, int psize) { unsigned long set = pte_val(entry) & (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_EXEC); unsigned long clr = ~pte_val(entry) & _PAGE_RO; int huge = psize > mmu_virtual_psize ? 1 : 0; + pmd_t *pmdp = (pmd_t *)ptep; - pte_update(vma->vm_mm, address, ptep, clr, set, huge); + if (pmdp == pmd_off(vma->vm_mm, ALIGN_DOWN(address, SZ_8M))) { + pte_update(vma->vm_mm, address, pte_offset_kernel(pmdp, 0), clr, set, huge); + pte_update(vma->vm_mm, address, pte_offset_kernel(pmdp + 1, 0), clr, set, huge); + } else { + pte_update(vma->vm_mm, address, ptep, clr, set, huge); + } flush_tlb_page(vma, address); } #define __ptep_set_access_flags __ptep_set_access_flags -static inline unsigned long pgd_leaf_size(pgd_t pgd) -{ - if (pgd_val(pgd) & _PMD_PAGE_8M) - return SZ_8M; - return SZ_4M; -} - -#define pgd_leaf_size pgd_leaf_size - static inline unsigned long pte_leaf_size(pmd_t pmd, pte_t pte) { pte_basic_t val = pte_val(pte); + if (pmd_val(pmd) & _PMD_PAGE_8M) + return SZ_8M; if (val & _PAGE_HUGE) return SZ_512K; if (val & _PAGE_SPS) @@ -168,17 +170,16 @@ static inline unsigned long pte_leaf_size(pmd_t pmd, pte_t pte) * On the 8xx, the page tables are a bit special. For 16k pages, we have * 4 identical entries. For 512k pages, we have 128 entries as if it was * 4k pages, but they are flagged as 512k pages for the hardware. - * For other page sizes, we have a single entry in the table. + * For 8M pages, we have 1024 entries as if it was + * 4M pages, but they are flagged as 8M pages for the hardware. + * For 4k pages, we have a single entry in the table. */ -static pmd_t *pmd_off(struct mm_struct *mm, unsigned long addr); -static int hugepd_ok(hugepd_t hpd); - static inline int number_of_cells_per_pte(pmd_t *pmd, pte_basic_t val, int huge) { if (!huge) return PAGE_SIZE / SZ_4K; - else if (hugepd_ok(*((hugepd_t *)pmd))) - return 1; + else if ((pmd_val(*pmd) & _PMD_PAGE_MASK) == _PMD_PAGE_8M) + return SZ_4M / SZ_4K; else if (IS_ENABLED(CONFIG_PPC_4K_PAGES) && !(val & _PAGE_HUGE)) return SZ_16K / SZ_4K; else @@ -198,7 +199,7 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p for (i = 0; i < num; i += PAGE_SIZE / SZ_4K, new += PAGE_SIZE) { *entry++ = new; - if (IS_ENABLED(CONFIG_PPC_16K_PAGES) && num != 1) { + if (IS_ENABLED(CONFIG_PPC_16K_PAGES)) { *entry++ = new; *entry++ = new; *entry++ = new; @@ -221,6 +222,28 @@ static inline pte_t ptep_get(pte_t *ptep) } #endif /* CONFIG_PPC_16K_PAGES */ +static inline void pmd_populate_kernel_size(struct mm_struct *mm, pmd_t *pmdp, + pte_t *pte, unsigned long sz) +{ + if (sz == SZ_8M) + *pmdp = __pmd(__pa(pte) | _PMD_PRESENT | _PMD_PAGE_8M); + else + *pmdp = __pmd(__pa(pte) | _PMD_PRESENT); +} + +static inline void pmd_populate_size(struct mm_struct *mm, pmd_t *pmdp, + pgtable_t pte_page, unsigned long sz) +{ + if (sz == SZ_8M) + *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT | _PMD_PAGE_8M); + else + *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT); +} +#define pmd_populate_size pmd_populate_size + +#define pmd_populate(mm, pmdp, pte) pmd_populate_size(mm, pmdp, pte, PAGE_SIZE) +#define pmd_populate_kernel(mm, pmdp, pte) pmd_populate_kernel_size(mm, pmdp, pte, PAGE_SIZE) + #endif #endif /* __KERNEL__ */ diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h index ac3353f7f2ac..c4be7754e96f 100644 --- a/arch/powerpc/include/asm/nohash/pgtable.h +++ b/arch/powerpc/include/asm/nohash/pgtable.h @@ -343,12 +343,8 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, #ifdef CONFIG_ARCH_HAS_HUGEPD static inline int hugepd_ok(hugepd_t hpd) { -#ifdef CONFIG_PPC_8xx - return ((hpd_val(hpd) & _PMD_PAGE_MASK) == _PMD_PAGE_8M); -#else /* We clear the top bit to indicate hugepd */ return (hpd_val(hpd) && (hpd_val(hpd) & PD_HUGE) == 0); -#endif } #define is_hugepd(hpd) (hugepd_ok(hpd)) diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h index e411e5a70ea3..018c3d55232c 100644 --- a/arch/powerpc/include/asm/page.h +++ b/arch/powerpc/include/asm/page.h @@ -293,13 +293,8 @@ static inline const void *pfn_to_kaddr(unsigned long pfn) /* * Some number of bits at the level of the page table that points to * a hugepte are used to encode the size. This masks those bits. - * On 8xx, HW assistance requires 4k alignment for the hugepte. */ -#ifdef CONFIG_PPC_8xx -#define HUGEPD_SHIFT_MASK 0xfff -#else #define HUGEPD_SHIFT_MASK 0x3f -#endif #ifndef __ASSEMBLY__ diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index 239709a2f68e..264a6c09517a 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -106,6 +106,9 @@ unsigned long vmalloc_to_phys(void *vmalloc_addr); void pgtable_cache_add(unsigned int shift); +#ifdef CONFIG_PPC32 +void __init *early_alloc_pgtable(unsigned long size); +#endif pte_t *early_pte_alloc_kernel(pmd_t *pmdp, unsigned long va); #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_PPC32) diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 647b0b445e89..43919ae0bd11 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -415,14 +415,13 @@ FixupDAR:/* Entry point for dcbx workaround. */ oris r11, r11, (swapper_pg_dir - PAGE_OFFSET)@ha 3: lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ + rlwinm r11, r11, 0, ~_PMD_PAGE_8M mtspr SPRN_MD_TWC, r11 - mtcrf 0x01, r11 mfspr r11, SPRN_MD_TWC lwz r11, 0(r11) /* Get the pte */ - bt 28,200f /* bit 28 = Large page (8M) */ /* concat physical page address(r11) and page offset(r10) */ rlwimi r11, r10, 0, 32 - PAGE_SHIFT, 31 -201: lwz r11,0(r11) + lwz r11,0(r11) /* Check if it really is a dcbx instruction. */ /* dcbt and dcbtst does not generate DTLB Misses/Errors, * no need to include them here */ @@ -441,11 +440,6 @@ FixupDAR:/* Entry point for dcbx workaround. */ 141: mfspr r10,SPRN_M_TW b DARFixed /* Nope, go back to normal TLB processing */ -200: - /* concat physical page address(r11) and page offset(r10) */ - rlwimi r11, r10, 0, 32 - PAGE_SHIFT_8M, 31 - b 201b - 144: mfspr r10, SPRN_DSISR rlwinm r10, r10,0,7,5 /* Clear store bit for buggy dcbst insn */ mtspr SPRN_DSISR, r10 diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index 82495b8ea793..42b12e1ec851 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -183,9 +183,6 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, if (!hpdp) return NULL; - if (IS_ENABLED(CONFIG_PPC_8xx) && pshift < PMD_SHIFT) - return pte_alloc_huge(mm, (pmd_t *)hpdp, addr, sz); - BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp)); if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, @@ -198,10 +195,18 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long sz) { + pmd_t *pmd = pmd_off(mm, addr); + if (sz < PMD_SIZE) - return pte_alloc_huge(mm, pmd_off(mm, addr), addr, sz); + return pte_alloc_huge(mm, pmd, addr, sz); - return NULL; + if (sz != SZ_8M) + return NULL; + if (!pte_alloc_huge(mm, pmd, addr, sz)) + return NULL; + if (!pte_alloc_huge(mm, pmd + 1, addr, sz)) + return NULL; + return (pte_t *)pmd; } #endif @@ -599,8 +604,7 @@ static int __init hugetlbpage_init(void) if (pdshift > shift) { if (!IS_ENABLED(CONFIG_PPC_8xx)) pgtable_cache_add(pdshift - shift); - } else if (IS_ENABLED(CONFIG_PPC_E500) || - IS_ENABLED(CONFIG_PPC_8xx)) { + } else if (IS_ENABLED(CONFIG_PPC_E500)) { pgtable_cache_add(PTE_T_ORDER); } diff --git a/arch/powerpc/mm/kasan/8xx.c b/arch/powerpc/mm/kasan/8xx.c index 2784224054f8..a4f33508cb6e 100644 --- a/arch/powerpc/mm/kasan/8xx.c +++ b/arch/powerpc/mm/kasan/8xx.c @@ -12,22 +12,25 @@ kasan_init_shadow_8M(unsigned long k_start, unsigned long k_end, void *block) pmd_t *pmd = pmd_off_k(k_start); unsigned long k_cur, k_next; - for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd += 2, block += SZ_8M) { - pte_basic_t *new; + for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd++, block += SZ_4M) { + pte_t *ptep; + int i; k_next = pgd_addr_end(k_cur, k_end); k_next = pgd_addr_end(k_next, k_end); if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte) continue; - new = memblock_alloc(sizeof(pte_basic_t), SZ_4K); + ptep = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE); if (!new) return -ENOMEM; - *new = pte_val(pte_mkhuge(pfn_pte(PHYS_PFN(__pa(block)), PAGE_KERNEL))); + for (i = 0; i < PTRS_PER_PTE; i++) { + pte_t pte = pte_mkhuge(pfn_pte(PHYS_PFN(__pa(block + i * PAGE_SIZE)), PAGE_KERNEL)); - hugepd_populate_kernel((hugepd_t *)pmd, (pte_t *)new, PAGE_SHIFT_8M); - hugepd_populate_kernel((hugepd_t *)pmd + 1, (pte_t *)new, PAGE_SHIFT_8M); + __set_pte_at(&init_mm, k_cur, ptep + i, pte, 1); + } + pmd_populate_kernel_size(&init_mm, pmd, ptep, SZ_8M); } return 0; } diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c index d93433e26ded..99f656b3f9f3 100644 --- a/arch/powerpc/mm/nohash/8xx.c +++ b/arch/powerpc/mm/nohash/8xx.c @@ -48,20 +48,6 @@ unsigned long p_block_mapped(phys_addr_t pa) return 0; } -static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va) -{ - if (hpd_val(*pmdp) == 0) { - pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K); - - if (!ptep) - return NULL; - - hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M); - hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M); - } - return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); -} - static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa, pgprot_t prot, int psize, bool new) { @@ -75,24 +61,33 @@ static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa, if (WARN_ON(slab_is_available())) return -EINVAL; - if (psize == MMU_PAGE_512K) + if (psize == MMU_PAGE_8M) { + if (WARN_ON(!pmd_none(*pmdp) || !pmd_none(*(pmdp + 1)))) + return -EINVAL; + + ptep = early_alloc_pgtable(PTE_FRAG_SIZE); + pmd_populate_kernel_size(&init_mm, pmdp, ptep, SZ_8M); + + ptep = early_alloc_pgtable(PTE_FRAG_SIZE); + pmd_populate_kernel_size(&init_mm, pmdp + 1, ptep, SZ_8M); + + ptep = (pte_t *)pmdp; + } else { ptep = early_pte_alloc_kernel(pmdp, va); - else - ptep = early_hugepd_alloc_kernel((hugepd_t *)pmdp, va); + /* The PTE should never be already present */ + if (WARN_ON(pte_present(*ptep) && pgprot_val(prot))) + return -EINVAL; + } } else { - if (psize == MMU_PAGE_512K) - ptep = pte_offset_kernel(pmdp, va); + if (psize == MMU_PAGE_8M) + ptep = (pte_t *)pmdp; else - ptep = hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); + ptep = pte_offset_kernel(pmdp, va); } if (WARN_ON(!ptep)) return -ENOMEM; - /* The PTE should never be already present */ - if (new && WARN_ON(pte_present(*ptep) && pgprot_val(prot))) - return -EINVAL; - set_huge_pte_at(&init_mm, va, ptep, pte_mkhuge(pfn_pte(pa >> PAGE_SHIFT, prot)), 1UL << mmu_psize_to_shift(psize)); diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index acdf64c9b93e..59f0d7706d2f 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -297,11 +297,8 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, } #if defined(CONFIG_PPC_8xx) -void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, - pte_t pte, unsigned long sz) +static void __set_huge_pte_at(pmd_t *pmd, pte_t *ptep, pte_basic_t val) { - pmd_t *pmd = pmd_off(mm, addr); - pte_basic_t val; pte_basic_t *entry = (pte_basic_t *)ptep; int num, i; @@ -311,15 +308,26 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, */ VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep)); - pte = set_pte_filter(pte, addr); - - val = pte_val(pte); - num = number_of_cells_per_pte(pmd, val, 1); for (i = 0; i < num; i++, entry++, val += SZ_4K) *entry = val; } + +void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, + pte_t pte, unsigned long sz) +{ + pmd_t *pmdp = pmd_off(mm, addr); + + pte = set_pte_filter(pte, addr); + + if (sz == SZ_8M) { + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp, 0), pte_val(pte)); + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp + 1, 0), pte_val(pte) + SZ_4M); + } else { + __set_huge_pte_at(pmdp, ptep, pte_val(pte)); + } +} #endif #endif /* CONFIG_HUGETLB_PAGE */ diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index cfd622ebf774..787b22206386 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -48,7 +48,7 @@ notrace void __init early_ioremap_init(void) early_ioremap_setup(); } -static void __init *early_alloc_pgtable(unsigned long size) +void __init *early_alloc_pgtable(unsigned long size) { void *ptr = memblock_alloc(size, size); diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index b2d8c0da2ad9..fa4bb096b3ae 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -98,6 +98,7 @@ config PPC_BOOK3S_64 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION select ARCH_ENABLE_SPLIT_PMD_PTLOCK select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE + select ARCH_HAS_HUGEPD if HUGETLB_PAGE select ARCH_SUPPORTS_HUGETLBFS select ARCH_SUPPORTS_NUMA_BALANCING select HAVE_MOVE_PMD @@ -290,6 +291,7 @@ config PPC_BOOK3S config PPC_E500 select FSL_EMB_PERFMON bool + select ARCH_HAS_HUGEPD if HUGETLB_PAGE select ARCH_SUPPORTS_HUGETLBFS if PHYS_64BIT || PPC64 select PPC_SMP_MUXED_IPI select PPC_DOORBELL
In order to fit better with standard Linux page tables layout, add support for 8M pages using contiguous PTE entries in a standard page table. Page tables will then be populated with 1024 similar entries and two PMD entries will point to that page table. The PMD entries also get a flag to tell it is addressing an 8M page, this is required for the HW tablewalk assistance. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- arch/powerpc/Kconfig | 1 - arch/powerpc/include/asm/hugetlb.h | 11 +++- .../include/asm/nohash/32/hugetlb-8xx.h | 54 ++++++++---------- arch/powerpc/include/asm/nohash/32/pgalloc.h | 2 + arch/powerpc/include/asm/nohash/32/pte-8xx.h | 57 +++++++++++++------ arch/powerpc/include/asm/nohash/pgtable.h | 4 -- arch/powerpc/include/asm/page.h | 5 -- arch/powerpc/include/asm/pgtable.h | 3 + arch/powerpc/kernel/head_8xx.S | 10 +--- arch/powerpc/mm/hugetlbpage.c | 18 +++--- arch/powerpc/mm/kasan/8xx.c | 15 +++-- arch/powerpc/mm/nohash/8xx.c | 43 +++++++------- arch/powerpc/mm/pgtable.c | 24 +++++--- arch/powerpc/mm/pgtable_32.c | 2 +- arch/powerpc/platforms/Kconfig.cputype | 2 + 15 files changed, 139 insertions(+), 112 deletions(-)