diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index 0f8bb86995b405a6bfaf6da978c955aebf805304..86aa3745af7f65f1d1240bac863be9145eda91f2 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -20,7 +20,7 @@ config DEBUG_STACK_USAGE config DEBUG_PAGEALLOC bool "Debug page memory allocations" - depends on DEBUG_KERNEL && !SOFTWARE_SUSPEND && PPC32 + depends on DEBUG_KERNEL && !SOFTWARE_SUSPEND help Unmap pages from the kernel linear mapping after free_pages(). This results in a large slowdown, but helps to find certain types diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index aae08531701842e1506d45c9cdd2fc2e4190a64f..49618461defbda9a4e2017477c1326530281272e 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -100,6 +100,11 @@ unsigned int HPAGE_SHIFT; #ifdef CONFIG_PPC_64K_PAGES int mmu_ci_restrictions; #endif +#ifdef CONFIG_DEBUG_PAGEALLOC +static u8 *linear_map_hash_slots; +static unsigned long linear_map_hash_count; +static spinlock_t linear_map_hash_lock; +#endif /* CONFIG_DEBUG_PAGEALLOC */ /* There are definitions of page sizes arrays to be used when none * is provided by the firmware. @@ -152,11 +157,10 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend, for (vaddr = vstart, paddr = pstart; vaddr < vend; vaddr += step, paddr += step) { - unsigned long vpn, hash, hpteg; + unsigned long hash, hpteg; unsigned long vsid = get_kernel_vsid(vaddr); unsigned long va = (vsid << 28) | (vaddr & 0x0fffffff); - vpn = va >> shift; tmp_mode = mode; /* Make non-kernel text non-executable */ @@ -174,6 +178,10 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend, if (ret < 0) break; +#ifdef CONFIG_DEBUG_PAGEALLOC + if ((paddr >> PAGE_SHIFT) < linear_map_hash_count) + linear_map_hash_slots[paddr >> PAGE_SHIFT] = ret | 0x80; +#endif /* CONFIG_DEBUG_PAGEALLOC */ } return ret < 0 ? ret : 0; } @@ -281,6 +289,7 @@ static void __init htab_init_page_sizes(void) memcpy(mmu_psize_defs, mmu_psize_defaults_gp, sizeof(mmu_psize_defaults_gp)); found: +#ifndef CONFIG_DEBUG_PAGEALLOC /* * Pick a size for the linear mapping. Currently, we only support * 16M, 1M and 4K which is the default @@ -289,6 +298,7 @@ static void __init htab_init_page_sizes(void) mmu_linear_psize = MMU_PAGE_16M; else if (mmu_psize_defs[MMU_PAGE_1M].shift) mmu_linear_psize = MMU_PAGE_1M; +#endif /* CONFIG_DEBUG_PAGEALLOC */ #ifdef CONFIG_PPC_64K_PAGES /* @@ -303,12 +313,14 @@ static void __init htab_init_page_sizes(void) if (mmu_psize_defs[MMU_PAGE_64K].shift) { mmu_virtual_psize = MMU_PAGE_64K; mmu_vmalloc_psize = MMU_PAGE_64K; + if (mmu_linear_psize == MMU_PAGE_4K) + mmu_linear_psize = MMU_PAGE_64K; if (cpu_has_feature(CPU_FTR_CI_LARGE_PAGE)) mmu_io_psize = MMU_PAGE_64K; else mmu_ci_restrictions = 1; } -#endif +#endif /* CONFIG_PPC_64K_PAGES */ printk(KERN_DEBUG "Page orders: linear mapping = %d, " "virtual = %d, io = %d\n", @@ -476,6 +488,13 @@ void __init htab_initialize(void) mode_rw = _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_COHERENT | PP_RWXX; +#ifdef CONFIG_DEBUG_PAGEALLOC + linear_map_hash_count = lmb_end_of_DRAM() >> PAGE_SHIFT; + linear_map_hash_slots = __va(lmb_alloc_base(linear_map_hash_count, + 1, lmb.rmo_size)); + memset(linear_map_hash_slots, 0, linear_map_hash_count); +#endif /* CONFIG_DEBUG_PAGEALLOC */ + /* On U3 based machines, we need to reserve the DART area and * _NOT_ map it to avoid cache paradoxes as it's remapped non * cacheable later on @@ -842,3 +861,62 @@ void low_hash_fault(struct pt_regs *regs, unsigned long address) } bad_page_fault(regs, address, SIGBUS); } + +#ifdef CONFIG_DEBUG_PAGEALLOC +static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi) +{ + unsigned long hash, hpteg, vsid = get_kernel_vsid(vaddr); + unsigned long va = (vsid << 28) | (vaddr & 0x0fffffff); + unsigned long mode = _PAGE_ACCESSED | _PAGE_DIRTY | + _PAGE_COHERENT | PP_RWXX | HPTE_R_N; + int ret; + + hash = hpt_hash(va, PAGE_SHIFT); + hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); + + ret = ppc_md.hpte_insert(hpteg, va, __pa(vaddr), + mode, HPTE_V_BOLTED, mmu_linear_psize); + BUG_ON (ret < 0); + spin_lock(&linear_map_hash_lock); + BUG_ON(linear_map_hash_slots[lmi] & 0x80); + linear_map_hash_slots[lmi] = ret | 0x80; + spin_unlock(&linear_map_hash_lock); +} + +static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) +{ + unsigned long hash, hidx, slot, vsid = get_kernel_vsid(vaddr); + unsigned long va = (vsid << 28) | (vaddr & 0x0fffffff); + + hash = hpt_hash(va, PAGE_SHIFT); + spin_lock(&linear_map_hash_lock); + BUG_ON(!(linear_map_hash_slots[lmi] & 0x80)); + hidx = linear_map_hash_slots[lmi] & 0x7f; + linear_map_hash_slots[lmi] = 0; + spin_unlock(&linear_map_hash_lock); + if (hidx & _PTEIDX_SECONDARY) + hash = ~hash; + slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; + slot += hidx & _PTEIDX_GROUP_IX; + ppc_md.hpte_invalidate(slot, va, mmu_linear_psize, 0); +} + +void kernel_map_pages(struct page *page, int numpages, int enable) +{ + unsigned long flags, vaddr, lmi; + int i; + + local_irq_save(flags); + for (i = 0; i < numpages; i++, page++) { + vaddr = (unsigned long)page_address(page); + lmi = __pa(vaddr) >> PAGE_SHIFT; + if (lmi >= linear_map_hash_count) + continue; + if (enable) + kernel_map_linear_page(vaddr, lmi); + else + kernel_unmap_linear_page(vaddr, lmi); + } + local_irq_restore(flags); +} +#endif /* CONFIG_DEBUG_PAGEALLOC */