diff options
| -rw-r--r-- | mm/gup.c | 179 |
1 files changed, 94 insertions, 85 deletions
@@ -2826,11 +2826,11 @@ static bool gup_fast_folio_allowed(struct folio *folio, unsigned int flags) * also check pmd here to make sure pmd doesn't change (corresponds to * pmdp_collapse_flush() in the THP collapse code path). */ -static int gup_fast_pte_range(pmd_t pmd, pmd_t *pmdp, unsigned long addr, - unsigned long end, unsigned int flags, struct page **pages, - int *nr) +static unsigned long gup_fast_pte_range(pmd_t pmd, pmd_t *pmdp, + unsigned long addr, unsigned long end, + unsigned int flags, struct page **pages) { - int ret = 0; + unsigned long nr_pages = 0; pte_t *ptep, *ptem; ptem = ptep = pte_offset_map(&pmd, addr); @@ -2892,15 +2892,13 @@ static int gup_fast_pte_range(pmd_t pmd, pmd_t *pmdp, unsigned long addr, goto pte_unmap; } folio_set_referenced(folio); - pages[*nr] = page; - (*nr)++; + pages[nr_pages] = page; + nr_pages++; } while (ptep++, addr += PAGE_SIZE, addr != end); - ret = 1; - pte_unmap: pte_unmap(ptem); - return ret; + return nr_pages; } #else @@ -2913,21 +2911,21 @@ pte_unmap: * get_user_pages_fast_only implementation that can pin pages. Thus it's still * useful to have gup_fast_pmd_leaf even if we can't operate on ptes. */ -static int gup_fast_pte_range(pmd_t pmd, pmd_t *pmdp, unsigned long addr, - unsigned long end, unsigned int flags, struct page **pages, - int *nr) +static unsigned long gup_fast_pte_range(pmd_t pmd, pmd_t *pmdp, + unsigned long addr, unsigned long end, + unsigned int flags, struct page **pages) { return 0; } #endif /* CONFIG_ARCH_HAS_PTE_SPECIAL */ -static int gup_fast_pmd_leaf(pmd_t orig, pmd_t *pmdp, unsigned long addr, - unsigned long end, unsigned int flags, struct page **pages, - int *nr) +static unsigned long gup_fast_pmd_leaf(pmd_t orig, pmd_t *pmdp, + unsigned long addr, unsigned long end, + unsigned int flags, struct page **pages) { struct page *page; struct folio *folio; - int refs; + unsigned long nr_pages, i; /* See gup_fast_pte_range() */ if (pmd_protnone(orig)) @@ -2939,42 +2937,40 @@ static int gup_fast_pmd_leaf(pmd_t orig, pmd_t *pmdp, unsigned long addr, if (pmd_special(orig)) return 0; - refs = (end - addr) >> PAGE_SHIFT; + nr_pages = (end - addr) >> PAGE_SHIFT; page = pmd_page(orig) + ((addr & ~PMD_MASK) >> PAGE_SHIFT); - folio = try_grab_folio_fast(page, refs, flags); + folio = try_grab_folio_fast(page, nr_pages, flags); if (!folio) return 0; if (unlikely(pmd_val(orig) != pmd_val(pmdp_get_lockless(pmdp)))) { - gup_put_folio(folio, refs, flags); + gup_put_folio(folio, nr_pages, flags); return 0; } if (!gup_fast_folio_allowed(folio, flags)) { - gup_put_folio(folio, refs, flags); + gup_put_folio(folio, nr_pages, flags); return 0; } if (!pmd_write(orig) && gup_must_unshare(NULL, flags, &folio->page)) { - gup_put_folio(folio, refs, flags); + gup_put_folio(folio, nr_pages, flags); return 0; } - pages += *nr; - *nr += refs; - for (; refs; refs--) + for (i = 0; i < nr_pages; i++) *(pages++) = page++; folio_set_referenced(folio); - return 1; + return nr_pages; } -static int gup_fast_pud_leaf(pud_t orig, pud_t *pudp, unsigned long addr, - unsigned long end, unsigned int flags, struct page **pages, - int *nr) +static unsigned long gup_fast_pud_leaf(pud_t orig, pud_t *pudp, + unsigned long addr, unsigned long end, + unsigned int flags, struct page **pages) { struct page *page; struct folio *folio; - int refs; + unsigned long nr_pages, i; if (!pud_access_permitted(orig, flags & FOLL_WRITE)) return 0; @@ -2982,41 +2978,39 @@ static int gup_fast_pud_leaf(pud_t orig, pud_t *pudp, unsigned long addr, if (pud_special(orig)) return 0; - refs = (end - addr) >> PAGE_SHIFT; + nr_pages = (end - addr) >> PAGE_SHIFT; page = pud_page(orig) + ((addr & ~PUD_MASK) >> PAGE_SHIFT); - folio = try_grab_folio_fast(page, refs, flags); + folio = try_grab_folio_fast(page, nr_pages, flags); if (!folio) return 0; if (unlikely(pud_val(orig) != pud_val(pudp_get(pudp)))) { - gup_put_folio(folio, refs, flags); + gup_put_folio(folio, nr_pages, flags); return 0; } if (!gup_fast_folio_allowed(folio, flags)) { - gup_put_folio(folio, refs, flags); + gup_put_folio(folio, nr_pages, flags); return 0; } if (!pud_write(orig) && gup_must_unshare(NULL, flags, &folio->page)) { - gup_put_folio(folio, refs, flags); + gup_put_folio(folio, nr_pages, flags); return 0; } - pages += *nr; - *nr += refs; - for (; refs; refs--) + for (i = 0; i < nr_pages; i++) *(pages++) = page++; folio_set_referenced(folio); - return 1; + return nr_pages; } -static int gup_fast_pmd_range(pud_t *pudp, pud_t pud, unsigned long addr, - unsigned long end, unsigned int flags, struct page **pages, - int *nr) +static unsigned long gup_fast_pmd_range(pud_t *pudp, pud_t pud, + unsigned long addr, unsigned long end, + unsigned int flags, struct page **pages) { - unsigned long next; + unsigned long next, nr_pages = 0, chunk_nr_pages; pmd_t *pmdp; pmdp = pmd_offset_lockless(pudp, pud, addr); @@ -3025,26 +3019,30 @@ static int gup_fast_pmd_range(pud_t *pudp, pud_t pud, unsigned long addr, next = pmd_addr_end(addr, end); if (!pmd_present(pmd)) - return 0; + break; if (unlikely(pmd_leaf(pmd))) { - if (!gup_fast_pmd_leaf(pmd, pmdp, addr, next, flags, - pages, nr)) - return 0; - - } else if (!gup_fast_pte_range(pmd, pmdp, addr, next, flags, - pages, nr)) - return 0; + chunk_nr_pages = gup_fast_pmd_leaf(pmd, pmdp, addr, + next, flags, + &pages[nr_pages]); + + } else + chunk_nr_pages = gup_fast_pte_range(pmd, pmdp, addr, + next, flags, + &pages[nr_pages]); + nr_pages += chunk_nr_pages; + if (chunk_nr_pages != (next - addr) >> PAGE_SHIFT) + break; } while (pmdp++, addr = next, addr != end); - return 1; + return nr_pages; } -static int gup_fast_pud_range(p4d_t *p4dp, p4d_t p4d, unsigned long addr, - unsigned long end, unsigned int flags, struct page **pages, - int *nr) +static unsigned long gup_fast_pud_range(p4d_t *p4dp, p4d_t p4d, + unsigned long addr, unsigned long end, + unsigned int flags, struct page **pages) { - unsigned long next; + unsigned long next, nr_pages = 0, chunk_nr_pages; pud_t *pudp; pudp = pud_offset_lockless(p4dp, p4d, addr); @@ -3053,24 +3051,27 @@ static int gup_fast_pud_range(p4d_t *p4dp, p4d_t p4d, unsigned long addr, next = pud_addr_end(addr, end); if (unlikely(!pud_present(pud))) - return 0; - if (unlikely(pud_leaf(pud))) { - if (!gup_fast_pud_leaf(pud, pudp, addr, next, flags, - pages, nr)) - return 0; - } else if (!gup_fast_pmd_range(pudp, pud, addr, next, flags, - pages, nr)) - return 0; + break; + if (unlikely(pud_leaf(pud))) + chunk_nr_pages = gup_fast_pud_leaf(pud, pudp, addr, + next, flags, + &pages[nr_pages]); + else + chunk_nr_pages = gup_fast_pmd_range(pudp, pud, addr, + next, flags, + &pages[nr_pages]); + nr_pages += chunk_nr_pages; + if (chunk_nr_pages != (next - addr) >> PAGE_SHIFT) + break; } while (pudp++, addr = next, addr != end); - return 1; + return nr_pages; } -static int gup_fast_p4d_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr, - unsigned long end, unsigned int flags, struct page **pages, - int *nr) +static unsigned long gup_fast_p4d_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr, + unsigned long end, unsigned int flags, struct page **pages) { - unsigned long next; + unsigned long next, nr_pages = 0, chunk_nr_pages; p4d_t *p4dp; p4dp = p4d_offset_lockless(pgdp, pgd, addr); @@ -3079,20 +3080,23 @@ static int gup_fast_p4d_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr, next = p4d_addr_end(addr, end); if (!p4d_present(p4d)) - return 0; + break; BUILD_BUG_ON(p4d_leaf(p4d)); - if (!gup_fast_pud_range(p4dp, p4d, addr, next, flags, - pages, nr)) - return 0; + chunk_nr_pages = gup_fast_pud_range(p4dp, p4d, addr, next, + flags, &pages[nr_pages]); + nr_pages += chunk_nr_pages; + if (chunk_nr_pages != (next - addr) >> PAGE_SHIFT) + break; } while (p4dp++, addr = next, addr != end); - return 1; + return nr_pages; } -static void gup_fast_pgd_range(unsigned long addr, unsigned long end, - unsigned int flags, struct page **pages, int *nr) +static unsigned long gup_fast_pgd_range(unsigned long addr, + unsigned long end, unsigned int flags, + struct page **pages) { - unsigned long next; + unsigned long next, nr_pages = 0, chunk_nr_pages; pgd_t *pgdp; pgdp = pgd_offset(current->mm, addr); @@ -3101,17 +3105,23 @@ static void gup_fast_pgd_range(unsigned long addr, unsigned long end, next = pgd_addr_end(addr, end); if (pgd_none(pgd)) - return; + break; BUILD_BUG_ON(pgd_leaf(pgd)); - if (!gup_fast_p4d_range(pgdp, pgd, addr, next, flags, - pages, nr)) - return; + chunk_nr_pages = gup_fast_p4d_range(pgdp, pgd, addr, next, + flags, &pages[nr_pages]); + nr_pages += chunk_nr_pages; + if (chunk_nr_pages != (next - addr) >> PAGE_SHIFT) + break; } while (pgdp++, addr = next, addr != end); + + return nr_pages; } #else -static inline void gup_fast_pgd_range(unsigned long addr, unsigned long end, - unsigned int flags, struct page **pages, int *nr) +static inline unsigned long gup_fast_pgd_range(unsigned long addr, + unsigned long end, unsigned int flags, + struct page **pages) { + return 0; } #endif /* CONFIG_HAVE_GUP_FAST */ @@ -3129,8 +3139,7 @@ static bool gup_fast_permitted(unsigned long start, unsigned long end) static unsigned long gup_fast(unsigned long start, unsigned long end, unsigned int gup_flags, struct page **pages) { - unsigned long flags; - int nr_pinned = 0; + unsigned long flags, nr_pinned; unsigned seq; if (!IS_ENABLED(CONFIG_HAVE_GUP_FAST) || @@ -3154,7 +3163,7 @@ static unsigned long gup_fast(unsigned long start, unsigned long end, * that come from callers of tlb_remove_table_sync_one(). */ local_irq_save(flags); - gup_fast_pgd_range(start, end, gup_flags, pages, &nr_pinned); + nr_pinned = gup_fast_pgd_range(start, end, gup_flags, pages); local_irq_restore(flags); /* |