From 60ec5585496871345c1a8113d7b60ed9d9474866 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sat, 29 Oct 2005 18:16:34 -0700 Subject: [PATCH] mm: i386 sh sh64 ready for split ptlock Use pte_offset_map_lock, instead of pte_offset_map (or inappropriate pte_offset_kernel) and mm-wide page_table_lock, in sundry arch places. The i386 vm86 mark_screen_rdonly: yes, there was and is an assumption that the screen fits inside the one page table, as indeed it does. The sh __do_page_fault: which handles both kernel faults (without lock) and user mm faults (locked - though it set_pte without locking before). The sh64 flush_cache_range and helpers: which wrongly thought callers held page_table_lock before (only its tlb_start_vma did, and no longer does so); moved the flush loop down, and adjusted the large versus small range decision to consider a range which spans page tables as large. Signed-off-by: Hugh Dickins Acked-by: Paul Mundt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/sh64/mm/cache.c | 68 +++++++++++++++++++++++----------------------------- 1 file changed, 30 insertions(+), 38 deletions(-) (limited to 'arch/sh64/mm') diff --git a/arch/sh64/mm/cache.c b/arch/sh64/mm/cache.c index 3b87e25ea77..c0c1b21350d 100644 --- a/arch/sh64/mm/cache.c +++ b/arch/sh64/mm/cache.c @@ -584,32 +584,36 @@ static void sh64_dcache_purge_phy_page(unsigned long paddr) } } -static void sh64_dcache_purge_user_page(struct mm_struct *mm, unsigned long eaddr) +static void sh64_dcache_purge_user_pages(struct mm_struct *mm, + unsigned long addr, unsigned long end) { pgd_t *pgd; pmd_t *pmd; pte_t *pte; pte_t entry; + spinlock_t *ptl; unsigned long paddr; - /* NOTE : all the callers of this have mm->page_table_lock held, so the - following page table traversal is safe even on SMP/pre-emptible. */ - - if (!mm) return; /* No way to find physical address of page */ - pgd = pgd_offset(mm, eaddr); - if (pgd_bad(*pgd)) return; - - pmd = pmd_offset(pgd, eaddr); - if (pmd_none(*pmd) || pmd_bad(*pmd)) return; - - pte = pte_offset_kernel(pmd, eaddr); - entry = *pte; - if (pte_none(entry) || !pte_present(entry)) return; - - paddr = pte_val(entry) & PAGE_MASK; - - sh64_dcache_purge_coloured_phy_page(paddr, eaddr); - + if (!mm) + return; /* No way to find physical address of page */ + + pgd = pgd_offset(mm, addr); + if (pgd_bad(*pgd)) + return; + + pmd = pmd_offset(pgd, addr); + if (pmd_none(*pmd) || pmd_bad(*pmd)) + return; + + pte = pte_offset_map_lock(mm, pmd, addr, &ptl); + do { + entry = *pte; + if (pte_none(entry) || !pte_present(entry)) + continue; + paddr = pte_val(entry) & PAGE_MASK; + sh64_dcache_purge_coloured_phy_page(paddr, addr); + } while (pte++, addr += PAGE_SIZE, addr != end); + pte_unmap_unlock(pte - 1, ptl); } /****************************************************************************/ @@ -668,7 +672,7 @@ static void sh64_dcache_purge_user_range(struct mm_struct *mm, int n_pages; n_pages = ((end - start) >> PAGE_SHIFT); - if (n_pages >= 64) { + if (n_pages >= 64 || ((start ^ (end - 1)) & PMD_MASK)) { #if 1 sh64_dcache_purge_all(); #else @@ -707,20 +711,10 @@ static void sh64_dcache_purge_user_range(struct mm_struct *mm, } #endif } else { - /* 'Small' range */ - unsigned long aligned_start; - unsigned long eaddr; - unsigned long last_page_start; - - aligned_start = start & PAGE_MASK; - /* 'end' is 1 byte beyond the end of the range */ - last_page_start = (end - 1) & PAGE_MASK; - - eaddr = aligned_start; - while (eaddr <= last_page_start) { - sh64_dcache_purge_user_page(mm, eaddr); - eaddr += PAGE_SIZE; - } + /* Small range, covered by a single page table page */ + start &= PAGE_MASK; /* should already be so */ + end = PAGE_ALIGN(end); /* should already be so */ + sh64_dcache_purge_user_pages(mm, start, end); } return; } @@ -880,9 +874,7 @@ void flush_cache_range(struct vm_area_struct *vma, unsigned long start, addresses from the user address space specified by mm, after writing back any dirty data. - Note(1), 'end' is 1 byte beyond the end of the range to flush. - - Note(2), this is called with mm->page_table_lock held.*/ + Note, 'end' is 1 byte beyond the end of the range to flush. */ sh64_dcache_purge_user_range(mm, start, end); sh64_icache_inv_user_page_range(mm, start, end); @@ -898,7 +890,7 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long eaddr, unsigned the I-cache must be searched too in case the page in question is both writable and being executed from (e.g. stack trampolines.) - Note(1), this is called with mm->page_table_lock held. + Note, this is called with pte lock held. */ sh64_dcache_purge_phy_page(pfn << PAGE_SHIFT); -- cgit v1.2.3-18-g5258