diff options
author | David S. Miller <davem@davemloft.net> | 2013-02-19 13:20:08 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-02-28 05:38:34 -0800 |
commit | 77913178ddf081e3d9afe2f866fb36cc33904c92 (patch) | |
tree | e31b8d9efedb0f9a73c7771155dbfb944b33b30a /arch | |
parent | 9e84c1288f809abcb9d7bfaff0dc882627a1a56d (diff) |
sparc64: Handle hugepage TSB being NULL.
[ Upstream commit bcd896bae0166b4443503482a26ecf84d9ba60ab ]
Accomodate the possibility that the TSB might be NULL at
the point that update_mmu_cache() is invoked. This is
necessary because we will sometimes need to defer the TSB
allocation to the first fault that happens in the 'mm'.
Seperate out the hugepage PTE test into a seperate function
so that the logic is clearer.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/sparc/mm/init_64.c | 38 |
1 files changed, 22 insertions, 16 deletions
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index c3b72423c84..0d0bc392c35 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -314,16 +314,31 @@ static void __update_mmu_tsb_insert(struct mm_struct *mm, unsigned long tsb_inde struct tsb *tsb = mm->context.tsb_block[tsb_index].tsb; unsigned long tag; + if (unlikely(!tsb)) + return; + tsb += ((address >> tsb_hash_shift) & (mm->context.tsb_block[tsb_index].tsb_nentries - 1UL)); tag = (address >> 22UL); tsb_insert(tsb, tag, tte); } +#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) +static inline bool is_hugetlb_pte(pte_t pte) +{ + if ((tlb_type == hypervisor && + (pte_val(pte) & _PAGE_SZALL_4V) == _PAGE_SZHUGE_4V) || + (tlb_type != hypervisor && + (pte_val(pte) & _PAGE_SZALL_4U) == _PAGE_SZHUGE_4U)) + return true; + return false; +} +#endif + void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) { - unsigned long tsb_index, tsb_hash_shift, flags; struct mm_struct *mm; + unsigned long flags; pte_t pte = *ptep; if (tlb_type != hypervisor) { @@ -335,25 +350,16 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t * mm = vma->vm_mm; - tsb_index = MM_TSB_BASE; - tsb_hash_shift = PAGE_SHIFT; - spin_lock_irqsave(&mm->context.lock, flags); #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) - if (mm->context.tsb_block[MM_TSB_HUGE].tsb != NULL) { - if ((tlb_type == hypervisor && - (pte_val(pte) & _PAGE_SZALL_4V) == _PAGE_SZHUGE_4V) || - (tlb_type != hypervisor && - (pte_val(pte) & _PAGE_SZALL_4U) == _PAGE_SZHUGE_4U)) { - tsb_index = MM_TSB_HUGE; - tsb_hash_shift = HPAGE_SHIFT; - } - } + if (mm->context.huge_pte_count && is_hugetlb_pte(pte)) + __update_mmu_tsb_insert(mm, MM_TSB_HUGE, HPAGE_SHIFT, + address, pte_val(pte)); + else #endif - - __update_mmu_tsb_insert(mm, tsb_index, tsb_hash_shift, - address, pte_val(pte)); + __update_mmu_tsb_insert(mm, MM_TSB_BASE, PAGE_SHIFT, + address, pte_val(pte)); spin_unlock_irqrestore(&mm->context.lock, flags); } |