From: Christoph Hellwig <hch@xxxxxx> Subject: mm: move the powerpc hugepd code to mm/gup.c While only powerpc supports the hugepd case, the code is pretty generic and I'd like to keep all GUP internals in one place. Link: http://lkml.kernel.org/r/20190625143715.1689-15-hch@xxxxxx Signed-off-by: Christoph Hellwig <hch@xxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: David Miller <davem@xxxxxxxxxxxxx> Cc: James Hogan <jhogan@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Cc: Khalid Aziz <khalid.aziz@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Paul Burton <paul.burton@xxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/powerpc/Kconfig | 1 arch/powerpc/mm/hugetlbpage.c | 72 ---------------------------- include/linux/hugetlb.h | 18 ------- mm/Kconfig | 10 +++ mm/gup.c | 82 ++++++++++++++++++++++++++++++++ 5 files changed, 93 insertions(+), 90 deletions(-) --- a/arch/powerpc/Kconfig~mm-move-the-powerpc-hugepd-code-to-mm-gupc +++ a/arch/powerpc/Kconfig @@ -125,6 +125,7 @@ config PPC select ARCH_HAS_FORTIFY_SOURCE select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_HAS_KCOV + select ARCH_HAS_HUGEPD if HUGETLB_PAGE select ARCH_HAS_MMIOWB if PPC64 select ARCH_HAS_PHYS_TO_DMA select ARCH_HAS_PMEM_API if PPC64 --- a/arch/powerpc/mm/hugetlbpage.c~mm-move-the-powerpc-hugepd-code-to-mm-gupc +++ a/arch/powerpc/mm/hugetlbpage.c @@ -511,13 +511,6 @@ retry: return page; } -static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end, - unsigned long sz) -{ - unsigned long __boundary = (addr + sz) & ~(sz-1); - return (__boundary - 1 < end - 1) ? __boundary : end; -} - #ifdef CONFIG_PPC_MM_SLICES unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, unsigned long pgoff, @@ -665,68 +658,3 @@ void flush_dcache_icache_hugepage(struct } } } - -static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr, - unsigned long end, int write, struct page **pages, int *nr) -{ - unsigned long pte_end; - struct page *head, *page; - pte_t pte; - int refs; - - pte_end = (addr + sz) & ~(sz-1); - if (pte_end < end) - end = pte_end; - - pte = READ_ONCE(*ptep); - - if (!pte_access_permitted(pte, write)) - return 0; - - /* hugepages are never "special" */ - VM_BUG_ON(!pfn_valid(pte_pfn(pte))); - - refs = 0; - head = pte_page(pte); - - page = head + ((addr & (sz-1)) >> PAGE_SHIFT); - do { - VM_BUG_ON(compound_head(page) != head); - pages[*nr] = page; - (*nr)++; - page++; - refs++; - } while (addr += PAGE_SIZE, addr != end); - - if (!page_cache_add_speculative(head, refs)) { - *nr -= refs; - return 0; - } - - if (unlikely(pte_val(pte) != pte_val(*ptep))) { - /* Could be optimized better */ - *nr -= refs; - while (refs--) - put_page(head); - return 0; - } - - return 1; -} - -int gup_huge_pd(hugepd_t hugepd, unsigned long addr, unsigned int pdshift, - unsigned long end, int write, struct page **pages, int *nr) -{ - pte_t *ptep; - unsigned long sz = 1UL << hugepd_shift(hugepd); - unsigned long next; - - ptep = hugepte_offset(hugepd, addr, pdshift); - do { - next = hugepte_addr_end(addr, end, sz); - if (!gup_hugepte(ptep, sz, addr, end, write, pages, nr)) - return 0; - } while (ptep++, addr = next, addr != end); - - return 1; -} --- a/include/linux/hugetlb.h~mm-move-the-powerpc-hugepd-code-to-mm-gupc +++ a/include/linux/hugetlb.h @@ -16,29 +16,11 @@ struct user_struct; struct mmu_gather; #ifndef is_hugepd -/* - * Some architectures requires a hugepage directory format that is - * required to support multiple hugepage sizes. For example - * a4fe3ce76 "powerpc/mm: Allow more flexible layouts for hugepage pagetables" - * introduced the same on powerpc. This allows for a more flexible hugepage - * pagetable layout. - */ typedef struct { unsigned long pd; } hugepd_t; #define is_hugepd(hugepd) (0) #define __hugepd(x) ((hugepd_t) { (x) }) -static inline int gup_huge_pd(hugepd_t hugepd, unsigned long addr, - unsigned pdshift, unsigned long end, - int write, struct page **pages, int *nr) -{ - return 0; -} -#else -extern int gup_huge_pd(hugepd_t hugepd, unsigned long addr, - unsigned pdshift, unsigned long end, - int write, struct page **pages, int *nr); #endif - #ifdef CONFIG_HUGETLB_PAGE #include <linux/mempolicy.h> --- a/mm/gup.c~mm-move-the-powerpc-hugepd-code-to-mm-gupc +++ a/mm/gup.c @@ -1966,6 +1966,88 @@ static int __gup_device_huge_pud(pud_t p } #endif +#ifdef CONFIG_ARCH_HAS_HUGEPD +static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end, + unsigned long sz) +{ + unsigned long __boundary = (addr + sz) & ~(sz-1); + return (__boundary - 1 < end - 1) ? __boundary : end; +} + +static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr, + unsigned long end, int write, struct page **pages, int *nr) +{ + unsigned long pte_end; + struct page *head, *page; + pte_t pte; + int refs; + + pte_end = (addr + sz) & ~(sz-1); + if (pte_end < end) + end = pte_end; + + pte = READ_ONCE(*ptep); + + if (!pte_access_permitted(pte, write)) + return 0; + + /* hugepages are never "special" */ + VM_BUG_ON(!pfn_valid(pte_pfn(pte))); + + refs = 0; + head = pte_page(pte); + + page = head + ((addr & (sz-1)) >> PAGE_SHIFT); + do { + VM_BUG_ON(compound_head(page) != head); + pages[*nr] = page; + (*nr)++; + page++; + refs++; + } while (addr += PAGE_SIZE, addr != end); + + if (!page_cache_add_speculative(head, refs)) { + *nr -= refs; + return 0; + } + + if (unlikely(pte_val(pte) != pte_val(*ptep))) { + /* Could be optimized better */ + *nr -= refs; + while (refs--) + put_page(head); + return 0; + } + + return 1; +} + +static int gup_huge_pd(hugepd_t hugepd, unsigned long addr, + unsigned int pdshift, unsigned long end, int write, + struct page **pages, int *nr) +{ + pte_t *ptep; + unsigned long sz = 1UL << hugepd_shift(hugepd); + unsigned long next; + + ptep = hugepte_offset(hugepd, addr, pdshift); + do { + next = hugepte_addr_end(addr, end, sz); + if (!gup_hugepte(ptep, sz, addr, end, write, pages, nr)) + return 0; + } while (ptep++, addr = next, addr != end); + + return 1; +} +#else +static inline int gup_huge_pd(hugepd_t hugepd, unsigned long addr, + unsigned pdshift, unsigned long end, int write, + struct page **pages, int *nr) +{ + return 0; +} +#endif /* CONFIG_ARCH_HAS_HUGEPD */ + static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr, unsigned long end, unsigned int flags, struct page **pages, int *nr) { --- a/mm/Kconfig~mm-move-the-powerpc-hugepd-code-to-mm-gupc +++ a/mm/Kconfig @@ -769,4 +769,14 @@ config GUP_GET_PTE_LOW_HIGH config ARCH_HAS_PTE_SPECIAL bool +# +# Some architectures require a special hugepage directory format that is +# required to support multiple hugepage sizes. For example a4fe3ce76 +# "powerpc/mm: Allow more flexible layouts for hugepage pagetables" +# introduced it on powerpc. This allows for a more flexible hugepage +# pagetable layouts. +# +config ARCH_HAS_HUGEPD + bool + endmenu _
