diff options
Diffstat (limited to 'arch/powerpc/mm')
| -rw-r--r-- | arch/powerpc/mm/Makefile | 10 | ||||
| -rw-r--r-- | arch/powerpc/mm/fault.c | 16 | ||||
| -rw-r--r-- | arch/powerpc/mm/hash_low_32.S | 111 | ||||
| -rw-r--r-- | arch/powerpc/mm/hugetlbpage.c | 22 | ||||
| -rw-r--r-- | arch/powerpc/mm/init_32.c | 6 | ||||
| -rw-r--r-- | arch/powerpc/mm/mem.c | 6 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_context_32.c | 84 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_context_hash32.c | 103 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_context_hash64.c (renamed from arch/powerpc/mm/mmu_context_64.c) | 8 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_context_nohash.c | 397 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_decl.h | 65 | ||||
| -rw-r--r-- | arch/powerpc/mm/pgtable.c | 117 | ||||
| -rw-r--r-- | arch/powerpc/mm/pgtable_32.c | 56 | ||||
| -rw-r--r-- | arch/powerpc/mm/ppc_mmu_32.c | 10 | ||||
| -rw-r--r-- | arch/powerpc/mm/tlb_hash32.c (renamed from arch/powerpc/mm/tlb_32.c) | 4 | ||||
| -rw-r--r-- | arch/powerpc/mm/tlb_hash64.c (renamed from arch/powerpc/mm/tlb_64.c) | 86 | ||||
| -rw-r--r-- | arch/powerpc/mm/tlb_nohash.c | 209 | ||||
| -rw-r--r-- | arch/powerpc/mm/tlb_nohash_low.S | 166 |
18 files changed, 1192 insertions, 284 deletions
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile index e7392b45a5e..953cc4a1cde 100644 --- a/arch/powerpc/mm/Makefile +++ b/arch/powerpc/mm/Makefile @@ -6,17 +6,19 @@ ifeq ($(CONFIG_PPC64),y) EXTRA_CFLAGS += -mno-minimal-toc endif -obj-y := fault.o mem.o \ +obj-y := fault.o mem.o pgtable.o \ init_$(CONFIG_WORD_SIZE).o \ - pgtable_$(CONFIG_WORD_SIZE).o \ - mmu_context_$(CONFIG_WORD_SIZE).o + pgtable_$(CONFIG_WORD_SIZE).o +obj-$(CONFIG_PPC_MMU_NOHASH) += mmu_context_nohash.o tlb_nohash.o \ + tlb_nohash_low.o hash-$(CONFIG_PPC_NATIVE) := hash_native_64.o obj-$(CONFIG_PPC64) += hash_utils_64.o \ slb_low.o slb.o stab.o \ gup.o mmap.o $(hash-y) obj-$(CONFIG_PPC_STD_MMU_32) += ppc_mmu_32.o obj-$(CONFIG_PPC_STD_MMU) += hash_low_$(CONFIG_WORD_SIZE).o \ - tlb_$(CONFIG_WORD_SIZE).o + tlb_hash$(CONFIG_WORD_SIZE).o \ + mmu_context_hash$(CONFIG_WORD_SIZE).o obj-$(CONFIG_40x) += 40x_mmu.o obj-$(CONFIG_44x) += 44x_mmu.o obj-$(CONFIG_FSL_BOOKE) += fsl_booke_mmu.o diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 565b7a237c8..91c7b8636b8 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -30,6 +30,7 @@ #include <linux/kprobes.h> #include <linux/kdebug.h> +#include <asm/firmware.h> #include <asm/page.h> #include <asm/pgtable.h> #include <asm/mmu.h> @@ -283,7 +284,7 @@ good_area: } pte_update(ptep, 0, _PAGE_HWEXEC | _PAGE_ACCESSED); - _tlbie(address, mm->context.id); + local_flush_tlb_page(vma, address); pte_unmap_unlock(ptep, ptl); up_read(&mm->mmap_sem); return 0; @@ -318,9 +319,16 @@ good_area: goto do_sigbus; BUG(); } - if (ret & VM_FAULT_MAJOR) + if (ret & VM_FAULT_MAJOR) { current->maj_flt++; - else +#ifdef CONFIG_PPC_SMLPAR + if (firmware_has_feature(FW_FEATURE_CMO)) { + preempt_disable(); + get_lppaca()->page_ins += (1 << PAGE_FACTOR); + preempt_enable(); + } +#endif + } else current->min_flt++; up_read(&mm->mmap_sem); return 0; @@ -339,7 +347,7 @@ bad_area_nosemaphore: && printk_ratelimit()) printk(KERN_CRIT "kernel tried to execute NX-protected" " page (%lx) - exploit attempt? (uid: %d)\n", - address, current->uid); + address, current_uid()); return SIGSEGV; diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S index 7bffb70b9fe..67850ec9feb 100644 --- a/arch/powerpc/mm/hash_low_32.S +++ b/arch/powerpc/mm/hash_low_32.S @@ -36,36 +36,6 @@ mmu_hash_lock: #endif /* CONFIG_SMP */ /* - * Sync CPUs with hash_page taking & releasing the hash - * table lock - */ -#ifdef CONFIG_SMP - .text -_GLOBAL(hash_page_sync) - mfmsr r10 - rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ - mtmsr r0 - lis r8,mmu_hash_lock@h - ori r8,r8,mmu_hash_lock@l - lis r0,0x0fff - b 10f -11: lwz r6,0(r8) - cmpwi 0,r6,0 - bne 11b -10: lwarx r6,0,r8 - cmpwi 0,r6,0 - bne- 11b - stwcx. r0,0,r8 - bne- 10b - isync - eieio - li r0,0 - stw r0,0(r8) - mtmsr r10 - blr -#endif /* CONFIG_SMP */ - -/* * Load a PTE into the hash table, if possible. * The address is in r4, and r3 contains an access flag: * _PAGE_RW (0x400) if a write. @@ -353,8 +323,8 @@ _GLOBAL(create_hpte) ori r8,r8,0xe14 /* clear out reserved bits and M */ andc r8,r5,r8 /* PP = user? (rw&dirty? 2: 3): 0 */ BEGIN_FTR_SECTION - ori r8,r8,_PAGE_COHERENT /* set M (coherence required) */ -END_FTR_SECTION_IFSET(CPU_FTR_NEED_COHERENT) + rlwinm r8,r8,0,~_PAGE_COHERENT /* clear M (coherence not required) */ +END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT) #ifdef CONFIG_PTE_64BIT /* Put the XPN bits into the PTE */ rlwimi r8,r10,8,20,22 @@ -663,3 +633,80 @@ _GLOBAL(flush_hash_patch_B) SYNC_601 isync blr + +/* + * Flush an entry from the TLB + */ +_GLOBAL(_tlbie) +#ifdef CONFIG_SMP + rlwinm r8,r1,0,0,(31-THREAD_SHIFT) + lwz r8,TI_CPU(r8) + oris r8,r8,11 + mfmsr r10 + SYNC + rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ + rlwinm r0,r0,0,28,26 /* clear DR */ + mtmsr r0 + SYNC_601 + isync + lis r9,mmu_hash_lock@h + ori r9,r9,mmu_hash_lock@l + tophys(r9,r9) +10: lwarx r7,0,r9 + cmpwi 0,r7,0 + bne- 10b + stwcx. r8,0,r9 + bne- 10b + eieio + tlbie r3 + sync + TLBSYNC + li r0,0 + stw r0,0(r9) /* clear mmu_hash_lock */ + mtmsr r10 + SYNC_601 + isync +#else /* CONFIG_SMP */ + tlbie r3 + sync +#endif /* CONFIG_SMP */ + blr + +/* + * Flush the entire TLB. 603/603e only + */ +_GLOBAL(_tlbia) +#if defined(CONFIG_SMP) + rlwinm r8,r1,0,0,(31-THREAD_SHIFT) + lwz r8,TI_CPU(r8) + oris r8,r8,10 + mfmsr r10 + SYNC + rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ + rlwinm r0,r0,0,28,26 /* clear DR */ + mtmsr r0 + SYNC_601 + isync + lis r9,mmu_hash_lock@h + ori r9,r9,mmu_hash_lock@l + tophys(r9,r9) +10: lwarx r7,0,r9 + cmpwi 0,r7,0 + bne- 10b + stwcx. r8,0,r9 + bne- 10b + sync + tlbia + sync + TLBSYNC + li r0,0 + stw r0,0(r9) /* clear mmu_hash_lock */ + mtmsr r10 + SYNC_601 + isync +#else /* CONFIG_SMP */ + sync + tlbia + sync +#endif /* CONFIG_SMP */ + blr diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index f0c3b88d50f..201c7a5486c 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -53,8 +53,7 @@ unsigned int mmu_huge_psizes[MMU_PAGE_COUNT] = { }; /* initialize all to 0 */ /* Subtract one from array size because we don't need a cache for 4K since * is not a huge page size */ -#define huge_pgtable_cache(psize) (pgtable_cache[HUGEPTE_CACHE_NUM \ - + psize-1]) +#define HUGE_PGTABLE_INDEX(psize) (HUGEPTE_CACHE_NUM + psize - 1) #define HUGEPTE_CACHE_NAME(psize) (huge_pgtable_cache_name[psize]) static const char *huge_pgtable_cache_name[MMU_PAGE_COUNT] = { @@ -113,7 +112,7 @@ static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr, static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp, unsigned long address, unsigned int psize) { - pte_t *new = kmem_cache_zalloc(huge_pgtable_cache(psize), + pte_t *new = kmem_cache_zalloc(pgtable_cache[HUGE_PGTABLE_INDEX(psize)], GFP_KERNEL|__GFP_REPEAT); if (! new) @@ -121,7 +120,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp, spin_lock(&mm->page_table_lock); if (!hugepd_none(*hpdp)) - kmem_cache_free(huge_pgtable_cache(psize), new); + kmem_cache_free(pgtable_cache[HUGE_PGTABLE_INDEX(psize)], new); else hpdp->pd = (unsigned long)new | HUGEPD_OK; spin_unlock(&mm->page_table_lock); @@ -763,13 +762,14 @@ static int __init hugetlbpage_init(void) for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { if (mmu_huge_psizes[psize]) { - huge_pgtable_cache(psize) = kmem_cache_create( - HUGEPTE_CACHE_NAME(psize), - HUGEPTE_TABLE_SIZE(psize), - HUGEPTE_TABLE_SIZE(psize), - 0, - NULL); - if (!huge_pgtable_cache(psize)) + pgtable_cache[HUGE_PGTABLE_INDEX(psize)] = + kmem_cache_create( + HUGEPTE_CACHE_NAME(psize), + HUGEPTE_TABLE_SIZE(psize), + HUGEPTE_TABLE_SIZE(psize), + 0, + NULL); + if (!pgtable_cache[HUGE_PGTABLE_INDEX(psize)]) panic("hugetlbpage_init(): could not create %s"\ "\n", HUGEPTE_CACHE_NAME(psize)); } diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c index 388ceda632f..666a5e8a5be 100644 --- a/arch/powerpc/mm/init_32.c +++ b/arch/powerpc/mm/init_32.c @@ -35,7 +35,6 @@ #include <asm/pgalloc.h> #include <asm/prom.h> #include <asm/io.h> -#include <asm/mmu_context.h> #include <asm/pgtable.h> #include <asm/mmu.h> #include <asm/smp.h> @@ -49,7 +48,7 @@ #if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL) /* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */ -#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE)) +#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - PAGE_OFFSET)) #error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL" #endif #endif @@ -180,9 +179,6 @@ void __init MMU_init(void) if (ppc_md.progress) ppc_md.progress("MMU:setio", 0x302); - /* Initialize the context management stuff */ - mmu_context_init(); - if (ppc_md.progress) ppc_md.progress("MMU:exit", 0x211); diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index b9e1a1da6e5..53b06ebb3f2 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -102,8 +102,8 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); if (!page_is_ram(pfn)) - vma_prot = __pgprot(pgprot_val(vma_prot) - | _PAGE_GUARDED | _PAGE_NO_CACHE); + vma_prot = pgprot_noncached(vma_prot); + return vma_prot; } EXPORT_SYMBOL(phys_mem_access_prot); @@ -488,7 +488,7 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, * we invalidate the TLB here, thus avoiding dcbst * misbehaviour. */ - _tlbie(address, 0 /* 8xx doesn't care about PID */); + _tlbil_va(address, 0 /* 8xx doesn't care about PID */); #endif /* The _PAGE_USER test should really be _PAGE_EXEC, but * older glibc versions execute some code from no-exec diff --git a/arch/powerpc/mm/mmu_context_32.c b/arch/powerpc/mm/mmu_context_32.c deleted file mode 100644 index cc32ba41d90..00000000000 --- a/arch/powerpc/mm/mmu_context_32.c +++ /dev/null @@ -1,84 +0,0 @@ -/* - * This file contains the routines for handling the MMU on those - * PowerPC implementations where the MMU substantially follows the - * architecture specification. This includes the 6xx, 7xx, 7xxx, - * 8260, and POWER3 implementations but excludes the 8xx and 4xx. - * -- paulus - * - * Derived from arch/ppc/mm/init.c: - * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) - * - * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) - * and Cort Dougan (PReP) (cort@cs.nmt.edu) - * Copyright (C) 1996 Paul Mackerras - * - * Derived from "arch/i386/mm/init.c" - * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - */ - -#include <linux/mm.h> -#include <linux/init.h> - -#include <asm/mmu_context.h> -#include <asm/tlbflush.h> - -unsigned long next_mmu_context; -unsigned long context_map[LAST_CONTEXT / BITS_PER_LONG + 1]; -#ifdef FEW_CONTEXTS -atomic_t nr_free_contexts; -struct mm_struct *context_mm[LAST_CONTEXT+1]; -void steal_context(void); -#endif /* FEW_CONTEXTS */ - -/* - * Initialize the context management stuff. - */ -void __init -mmu_context_init(void) -{ - /* - * Some processors have too few contexts to reserve one for - * init_mm, and require using context 0 for a normal task. - * Other processors reserve the use of context zero for the kernel. - * This code assumes FIRST_CONTEXT < 32. - */ - context_map[0] = (1 << FIRST_CONTEXT) - 1; - next_mmu_context = FIRST_CONTEXT; -#ifdef FEW_CONTEXTS - atomic_set(&nr_free_contexts, LAST_CONTEXT - FIRST_CONTEXT + 1); -#endif /* FEW_CONTEXTS */ -} - -#ifdef FEW_CONTEXTS -/* - * Steal a context from a task that has one at the moment. - * This is only used on 8xx and 4xx and we presently assume that - * they don't do SMP. If they do then this will have to check - * whether the MM we steal is in use. - * We also assume that this is only used on systems that don't - * use an MMU hash table - this is true for 8xx and 4xx. - * This isn't an LRU system, it just frees up each context in - * turn (sort-of pseudo-random replacement :). This would be the - * place to implement an LRU scheme if anyone was motivated to do it. - * -- paulus - */ -void -steal_context(void) -{ - struct mm_struct *mm; - - /* free up context `next_mmu_context' */ - /* if we shouldn't free context 0, don't... */ - if (next_mmu_context < FIRST_CONTEXT) - next_mmu_context = FIRST_CONTEXT; - mm = context_mm[next_mmu_context]; - flush_tlb_mm(mm); - destroy_context(mm); -} -#endif /* FEW_CONTEXTS */ diff --git a/arch/powerpc/mm/mmu_context_hash32.c b/arch/powerpc/mm/mmu_context_hash32.c new file mode 100644 index 00000000000..0dfba2bf7f3 --- /dev/null +++ b/arch/powerpc/mm/mmu_context_hash32.c @@ -0,0 +1,103 @@ +/* + * This file contains the routines for handling the MMU on those + * PowerPC implementations where the MMU substantially follows the + * architecture specification. This includes the 6xx, 7xx, 7xxx, + * 8260, and POWER3 implementations but excludes the 8xx and 4xx. + * -- paulus + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ + +#include <linux/mm.h> +#include <linux/init.h> + +#include <asm/mmu_context.h> +#include <asm/tlbflush.h> + +/* + * On 32-bit PowerPC 6xx/7xx/7xxx CPUs, we use a set of 16 VSIDs + * (virtual segment identifiers) for each context. Although the + * hardware supports 24-bit VSIDs, and thus >1 million contexts, + * we only use 32,768 of them. That is ample, since there can be + * at most around 30,000 tasks in the system anyway, and it means + * that we can use a bitmap to indicate which contexts are in use. + * Using a bitmap means that we entirely avoid all of the problems + * that we used to have when the context number overflowed, + * particularly on SMP systems. + * -- paulus. + */ +#define NO_CONTEXT ((unsigned long) -1) +#define LAST_CONTEXT 32767 +#define FIRST_CONTEXT 1 + +/* + * This function defines the mapping from contexts to VSIDs (virtual + * segment IDs). We use a skew on both the context and the high 4 bits + * of the 32-bit virtual address (the "effective segment ID") in order + * to spread out the entries in the MMU hash table. Note, if this + * function is changed then arch/ppc/mm/hashtable.S will have to be + * changed to correspond. + * + * + * CTX_TO_VSID(ctx, va) (((ctx) * (897 * 16) + ((va) >> 28) * 0x111) \ + * & 0xffffff) + */ + +static unsigned long next_mmu_context; +static unsigned long context_map[LAST_CONTEXT / BITS_PER_LONG + 1]; + + +/* + * Set up the context for a new address space. + */ +int init_new_context(struct task_struct *t, struct mm_struct *mm) +{ + unsigned long ctx = next_mmu_context; + + while (test_and_set_bit(ctx, context_map)) { + ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx); + if (ctx > LAST_CONTEXT) + ctx = 0; + } + next_mmu_context = (ctx + 1) & LAST_CONTEXT; + mm->context.id = ctx; + + return 0; +} + +/* + * We're finished using the context for an address space. + */ +void destroy_context(struct mm_struct *mm) +{ + preempt_disable(); + if (mm->context.id != NO_CONTEXT) { + clear_bit(mm->context.id, context_map); + mm->context.id = NO_CONTEXT; + } + preempt_enable(); +} + +/* + * Initialize the context management stuff. + */ +void __init mmu_context_init(void) +{ + /* Reserve context 0 for kernel use */ + context_map[0] = (1 << FIRST_CONTEXT) - 1; + next_mmu_context = FIRST_CONTEXT; +} diff --git a/arch/powerpc/mm/mmu_context_64.c b/arch/powerpc/mm/mmu_context_hash64.c index 1db38ba1f54..dbeb86ac90c 100644 --- a/arch/powerpc/mm/mmu_context_64.c +++ b/arch/powerpc/mm/mmu_context_hash64.c @@ -24,6 +24,14 @@ static DEFINE_SPINLOCK(mmu_context_lock); static DEFINE_IDR(mmu_context_idr); +/* + * The proto-VSID space has 2^35 - 1 segments available for user mappings. + * Each segment contains 2^28 bytes. Each context maps 2^44 bytes, + * so we can support 2^19-1 contexts (19 == 35 + 28 - 44). + */ +#define NO_CONTEXT 0 +#define MAX_CONTEXT ((1UL << 19) - 1) + int init_new_context(struct task_struct *tsk, struct mm_struct *mm) { int index; diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c new file mode 100644 index 00000000000..52a0cfc38b6 --- /dev/null +++ b/arch/powerpc/mm/mmu_context_nohash.c @@ -0,0 +1,397 @@ +/* + * This file contains the routines for handling the MMU on those + * PowerPC implementations where the MMU is not using the hash + * table, such as 8xx, 4xx, BookE's etc... + * + * Copyright 2008 Ben Herrenschmidt <benh@kernel.crashing.org> + * IBM Corp. + * + * Derived from previous arch/powerpc/mm/mmu_context.c + * and arch/powerpc/include/asm/mmu_context.h + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * TODO: + * + * - The global context lock will not scale very well + * - The maps should be dynamically allocated to allow for processors + * that support more PID bits at runtime + * - Implement flush_tlb_mm() by making the context stale and picking + * a new one + * - More aggressively clear stale map bits and maybe find some way to + * also clear mm->cpu_vm_mask bits when processes are migrated + */ + +#undef DEBUG +#define DEBUG_STEAL_ONLY +#undef DEBUG_MAP_CONSISTENCY +/*#define DEBUG_CLAMP_LAST_CONTEXT 15 */ + +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/bootmem.h> +#include <linux/notifier.h> +#include <linux/cpu.h> + +#include <asm/mmu_context.h> +#include <asm/tlbflush.h> + +static unsigned int first_context, last_context; +static unsigned int next_context, nr_free_contexts; +static unsigned long *context_map; +static unsigned long *stale_map[NR_CPUS]; +static struct mm_struct **context_mm; +static spinlock_t context_lock = SPIN_LOCK_UNLOCKED; + +#define CTX_MAP_SIZE \ + (sizeof(unsigned long) * (last_context / BITS_PER_LONG + 1)) + + +/* Steal a context from a task that has one at the moment. + * + * This is used when we are running out of available PID numbers + * on the processors. + * + * This isn't an LRU system, it just frees up each context in + * turn (sort-of pseudo-random replacement :). This would be the + * place to implement an LRU scheme if anyone was motivated to do it. + * -- paulus + * + * For context stealing, we use a slightly different approach for + * SMP and UP. Basically, the UP one is simpler and doesn't use + * the stale map as we can just flush the local CPU + * -- benh + */ +#ifdef CONFIG_SMP +static unsigned int steal_context_smp(unsigned int id) +{ + struct mm_struct *mm; + unsigned int cpu, max; + + again: + max = last_context - first_context; + + /* Attempt to free next_context first and then loop until we manage */ + while (max--) { + /* Pick up the victim mm */ + mm = context_mm[id]; + + /* We have a candidate victim, check if it's active, on SMP + * we cannot steal active contexts + */ + if (mm->context.active) { + id++; + if (id > last_context) + id = first_context; + continue; + } + pr_debug("[%d] steal context %d from mm @%p\n", + smp_processor_id(), id, mm); + + /* Mark this mm has having no context anymore */ + mm->context.id = MMU_NO_CONTEXT; + + /* Mark it stale on all CPUs that used this mm */ + for_each_cpu_mask_nr(cpu, mm->cpu_vm_mask) + __set_bit(id, stale_map[cpu]); + return id; + } + + /* This will happen if you have more CPUs than available contexts, + * all we can do here is wait a bit and try again + */ + spin_unlock(&context_lock); + cpu_relax(); + spin_lock(&context_lock); + goto again; +} +#endif /* CONFIG_SMP */ + +/* Note that this will also be called on SMP if all other CPUs are + * offlined, which means that it may be called for cpu != 0. For + * this to work, we somewhat assume that CPUs that are onlined + * come up with a fully clean TLB (or are cleaned when offlined) + */ +static unsigned int steal_context_up(unsigned int id) +{ + struct mm_struct *mm; + int cpu = smp_processor_id(); + + /* Pick up the victim mm */ + mm = context_mm[id]; + + pr_debug("[%d] steal context %d from mm @%p\n", cpu, id, mm); + + /* Mark this mm has having no context anymore */ + mm->context.id = MMU_NO_CONTEXT; + + /* Flush the TLB for that context */ + local_flush_tlb_mm(mm); + + /* XXX This clear should ultimately be part of local_flush_tlb_mm */ + __clear_bit(id, stale_map[cpu]); + + return id; +} + +#ifdef DEBUG_MAP_CONSISTENCY +static void context_check_map(void) +{ + unsigned int id, nrf, nact; + + nrf = nact = 0; + for (id = first_context; id <= last_context; id++) { + int used = test_bit(id, context_map); + if (!used) + nrf++; + if (used != (context_mm[id] != NULL)) + pr_err("MMU: Context %d is %s and MM is %p !\n", + id, used ? "used" : "free", context_mm[id]); + if (context_mm[id] != NULL) + nact += context_mm[id]->context.active; + } + if (nrf != nr_free_contexts) { + pr_err("MMU: Free context count out of sync ! (%d vs %d)\n", + nr_free_contexts, nrf); + nr_free_contexts = nrf; + } + if (nact > num_online_cpus()) + pr_err("MMU: More active contexts than CPUs ! (%d vs %d)\n", + nact, num_online_cpus()); + if (first_context > 0 && !test_bit(0, context_map)) + pr_err("MMU: Context 0 has been freed !!!\n"); +} +#else +static void context_check_map(void) { } +#endif + +void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next) +{ + unsigned int id, cpu = smp_processor_id(); + unsigned long *map; + + /* No lockless fast path .. yet */ + spin_lock(&context_lock); + +#ifndef DEBUG_STEAL_ONLY + pr_debug("[%d] activating context for mm @%p, active=%d, id=%d\n", + cpu, next, next->context.active, next->context.id); +#endif + +#ifdef CONFIG_SMP + /* Mark us active and the previous one not anymore */ + next->context.active++; + if (prev) { +#ifndef DEBUG_STEAL_ONLY + pr_debug(" old context %p active was: %d\n", + prev, prev->context.active); +#endif + WARN_ON(prev->context.active < 1); + prev->context.active--; + } +#endif /* CONFIG_SMP */ + + /* If we already have a valid assigned context, skip all that */ + id = next->context.id; + if (likely(id != MMU_NO_CONTEXT)) + goto ctxt_ok; + + /* We really don't have a context, let's try to acquire one */ + id = next_context; + if (id > last_context) + id = first_context; + map = context_map; + + /* No more free contexts, let's try to steal one */ + if (nr_free_contexts == 0) { +#ifdef CONFIG_SMP + if (num_online_cpus() > 1) { + id = steal_context_smp(id); + goto stolen; + } +#endif /* CONFIG_SMP */ + id = steal_context_up(id); + goto stolen; + } + nr_free_contexts--; + + /* We know there's at least one free context, try to find it */ + while (__test_and_set_bit(id, map)) { + id = find_next_zero_bit(map, last_context+1, id); + if (id > last_context) + id = first_context; + } + stolen: + next_context = id + 1; + context_mm[id] = next; + next->context.id = id; + +#ifndef DEBUG_STEAL_ONLY + pr_debug("[%d] picked up new id %d, nrf is now %d\n", + cpu, id, nr_free_contexts); +#endif + + context_check_map(); + ctxt_ok: + + /* If that context got marked stale on this CPU, then flush the + * local TLB for it and unmark it before we use it + */ + if (test_bit(id, stale_map[cpu])) { + pr_debug("[%d] flushing stale context %d for mm @%p !\n", + cpu, id, next); + local_flush_tlb_mm(next); + + /* XXX This clear should ultimately be part of local_flush_tlb_mm */ + __clear_bit(id, stale_map[cpu]); + } + + /* Flick the MMU and release lock */ + set_context(id, next->pgd); + spin_unlock(&context_lock); +} + +/* + * Set up the context for a new address space. + */ +int init_new_context(struct task_struct *t, struct mm_struct *mm) +{ + mm->context.id = MMU_NO_CONTEXT; + mm->context.active = 0; + + return 0; +} + +/* + * We're finished using the context for an address space. + */ +void destroy_context(struct mm_struct *mm) +{ + unsigned int id; + + if (mm->context.id == MMU_NO_CONTEXT) + return; + + WARN_ON(mm->context.active != 0); + + spin_lock(&context_lock); + id = mm->context.id; + if (id != MMU_NO_CONTEXT) { + __clear_bit(id, context_map); + mm->context.id = MMU_NO_CONTEXT; +#ifdef DEBUG_MAP_CONSISTENCY + mm->context.active = 0; + context_mm[id] = NULL; +#endif + nr_free_contexts++; + } + spin_unlock(&context_lock); +} + +#ifdef CONFIG_SMP + +static int __cpuinit mmu_context_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + unsigned int cpu = (unsigned int)(long)hcpu; + + /* We don't touch CPU 0 map, it's allocated at aboot and kept + * around forever + */ + if (cpu == 0) + return NOTIFY_OK; + + switch (action) { + case CPU_ONLINE: + case CPU_ONLINE_FROZEN: + pr_debug("MMU: Allocating stale context map for CPU %d\n", cpu); + stale_map[cpu] = kzalloc(CTX_MAP_SIZE, GFP_KERNEL); + break; +#ifdef CONFIG_HOTPLUG_CPU + case CPU_DEAD: + case CPU_DEAD_FROZEN: + pr_debug("MMU: Freeing stale context map for CPU %d\n", cpu); + kfree(stale_map[cpu]); + stale_map[cpu] = NULL; + break; +#endif + } + return NOTIFY_OK; +} + +static struct notifier_block __cpuinitdata mmu_context_cpu_nb = { + .notifier_call = mmu_context_cpu_notify, +}; + +#endif /* CONFIG_SMP */ + +/* + * Initialize the context management stuff. + */ +void __init mmu_context_init(void) +{ + /* Mark init_mm as being active on all possible CPUs since + * we'll get called with prev == init_mm the first time + * we schedule on a given CPU + */ + init_mm.context.active = NR_CPUS; + + /* + * The MPC8xx has only 16 contexts. We rotate through them on each + * task switch. A better way would be to keep track of tasks that + * own contexts, and implement an LRU usage. That way very active + * tasks don't always have to pay the TLB reload overhead. The + * kernel pages are mapped shared, so the kernel can run on behalf + * of any task that makes a kernel entry. Shared does not mean they + * are not protected, just that the ASID comparison is not performed. + * -- Dan + * + * The IBM4xx has 256 contexts, so we can just rotate through these + * as a way of "switching" contexts. If the TID of the TLB is zero, + * the PID/TID comparison is disabled, so we can use a TID of zero + * to represent all kernel pages as shared among all contexts. + * -- Dan + */ + if (mmu_has_feature(MMU_FTR_TYPE_8xx)) { + first_context = 0; + last_context = 15; + } else { + first_context = 1; + last_context = 255; + } + +#ifdef DEBUG_CLAMP_LAST_CONTEXT + last_context = DEBUG_CLAMP_LAST_CONTEXT; +#endif + /* + * Allocate the maps used by context management + */ + context_map = alloc_bootmem(CTX_MAP_SIZE); + context_mm = alloc_bootmem(sizeof(void *) * (last_context + 1)); + stale_map[0] = alloc_bootmem(CTX_MAP_SIZE); + +#ifdef CONFIG_SMP + register_cpu_notifier(&mmu_context_cpu_nb); +#endif + + printk(KERN_INFO + "MMU: Allocated %d bytes of context maps for %d contexts\n", + 2 * CTX_MAP_SIZE + (sizeof(void *) * (last_context + 1)), + last_context - first_context + 1); + + /* + * Some processors have too few contexts to reserve one for + * init_mm, and require using context 0 for a normal task. + * Other processors reserve the use of context zero for the kernel. + * This code assumes first_context < 32. + */ + context_map[0] = (1 << first_context) - 1; + next_context = first_context; + nr_free_contexts = last_context - first_context + 1; +} + diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index fab3cfad409..4314b39b6fa 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -22,10 +22,58 @@ #include <asm/tlbflush.h> #include <asm/mmu.h> +#ifdef CONFIG_PPC_MMU_NOHASH + +/* + * On 40x and 8xx, we directly inline tlbia and tlbivax + */ +#if defined(CONFIG_40x) || defined(CONFIG_8xx) +static inline void _tlbil_all(void) +{ + asm volatile ("sync; tlbia; isync" : : : "memory") +} +static inline void _tlbil_pid(unsigned int pid) +{ + asm volatile ("sync; tlbia; isync" : : : "memory") +} +#else /* CONFIG_40x || CONFIG_8xx */ +extern void _tlbil_all(void); +extern void _tlbil_pid(unsigned int pid); +#endif /* !(CONFIG_40x || CONFIG_8xx) */ + +/* + * On 8xx, we directly inline tlbie, on others, it's extern + */ +#ifdef CONFIG_8xx +static inline void _tlbil_va(unsigned long address, unsigned int pid) +{ + asm volatile ("tlbie %0; sync" : : "r" (address) : "memory") +} +#else /* CONFIG_8xx */ +extern void _tlbil_va(unsigned long address, unsigned int pid); +#endif /* CONIFG_8xx */ + +/* + * As of today, we don't support tlbivax broadcast on any + * implementation. When that becomes the case, this will be + * an extern. + */ +static inline void _tlbivax_bcast(unsigned long address, unsigned int pid) +{ |