diff options
Diffstat (limited to 'arch/sparc64/mm/tsb.c')
-rw-r--r-- | arch/sparc64/mm/tsb.c | 496 |
1 files changed, 0 insertions, 496 deletions
diff --git a/arch/sparc64/mm/tsb.c b/arch/sparc64/mm/tsb.c deleted file mode 100644 index f0282fa..0000000 --- a/arch/sparc64/mm/tsb.c +++ /dev/null @@ -1,496 +0,0 @@ -/* arch/sparc64/mm/tsb.c - * - * Copyright (C) 2006, 2008 David S. Miller <davem@davemloft.net> - */ - -#include <linux/kernel.h> -#include <linux/preempt.h> -#include <asm/system.h> -#include <asm/page.h> -#include <asm/tlbflush.h> -#include <asm/tlb.h> -#include <asm/mmu_context.h> -#include <asm/pgtable.h> -#include <asm/tsb.h> -#include <asm/oplib.h> - -extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES]; - -static inline unsigned long tsb_hash(unsigned long vaddr, unsigned long hash_shift, unsigned long nentries) -{ - vaddr >>= hash_shift; - return vaddr & (nentries - 1); -} - -static inline int tag_compare(unsigned long tag, unsigned long vaddr) -{ - return (tag == (vaddr >> 22)); -} - -/* TSB flushes need only occur on the processor initiating the address - * space modification, not on each cpu the address space has run on. - * Only the TLB flush needs that treatment. - */ - -void flush_tsb_kernel_range(unsigned long start, unsigned long end) -{ - unsigned long v; - - for (v = start; v < end; v += PAGE_SIZE) { - unsigned long hash = tsb_hash(v, PAGE_SHIFT, - KERNEL_TSB_NENTRIES); - struct tsb *ent = &swapper_tsb[hash]; - - if (tag_compare(ent->tag, v)) - ent->tag = (1UL << TSB_TAG_INVALID_BIT); - } -} - -static void __flush_tsb_one(struct mmu_gather *mp, unsigned long hash_shift, unsigned long tsb, unsigned long nentries) -{ - unsigned long i; - - for (i = 0; i < mp->tlb_nr; i++) { - unsigned long v = mp->vaddrs[i]; - unsigned long tag, ent, hash; - - v &= ~0x1UL; - - hash = tsb_hash(v, hash_shift, nentries); - ent = tsb + (hash * sizeof(struct tsb)); - tag = (v >> 22UL); - - tsb_flush(ent, tag); - } -} - -void flush_tsb_user(struct mmu_gather *mp) -{ - struct mm_struct *mm = mp->mm; - unsigned long nentries, base, flags; - - spin_lock_irqsave(&mm->context.lock, flags); - - base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb; - nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries; - if (tlb_type == cheetah_plus || tlb_type == hypervisor) - base = __pa(base); - __flush_tsb_one(mp, PAGE_SHIFT, base, nentries); - -#ifdef CONFIG_HUGETLB_PAGE - if (mm->context.tsb_block[MM_TSB_HUGE].tsb) { - base = (unsigned long) mm->context.tsb_block[MM_TSB_HUGE].tsb; - nentries = mm->context.tsb_block[MM_TSB_HUGE].tsb_nentries; - if (tlb_type == cheetah_plus || tlb_type == hypervisor) - base = __pa(base); - __flush_tsb_one(mp, HPAGE_SHIFT, base, nentries); - } -#endif - spin_unlock_irqrestore(&mm->context.lock, flags); -} - -#if defined(CONFIG_SPARC64_PAGE_SIZE_8KB) -#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_8K -#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_8K -#elif defined(CONFIG_SPARC64_PAGE_SIZE_64KB) -#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_64K -#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_64K -#else -#error Broken base page size setting... -#endif - -#ifdef CONFIG_HUGETLB_PAGE -#if defined(CONFIG_HUGETLB_PAGE_SIZE_64K) -#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_64K -#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_64K -#elif defined(CONFIG_HUGETLB_PAGE_SIZE_512K) -#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_512K -#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_512K -#elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB) -#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_4MB -#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_4MB -#else -#error Broken huge page size setting... -#endif -#endif - -static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_idx, unsigned long tsb_bytes) -{ - unsigned long tsb_reg, base, tsb_paddr; - unsigned long page_sz, tte; - - mm->context.tsb_block[tsb_idx].tsb_nentries = - tsb_bytes / sizeof(struct tsb); - - base = TSBMAP_BASE; - tte = pgprot_val(PAGE_KERNEL_LOCKED); - tsb_paddr = __pa(mm->context.tsb_block[tsb_idx].tsb); - BUG_ON(tsb_paddr & (tsb_bytes - 1UL)); - - /* Use the smallest page size that can map the whole TSB - * in one TLB entry. - */ - switch (tsb_bytes) { - case 8192 << 0: - tsb_reg = 0x0UL; -#ifdef DCACHE_ALIASING_POSSIBLE - base += (tsb_paddr & 8192); -#endif - page_sz = 8192; - break; - - case 8192 << 1: - tsb_reg = 0x1UL; - page_sz = 64 * 1024; - break; - - case 8192 << 2: - tsb_reg = 0x2UL; - page_sz = 64 * 1024; - break; - - case 8192 << 3: - tsb_reg = 0x3UL; - page_sz = 64 * 1024; - break; - - case 8192 << 4: - tsb_reg = 0x4UL; - page_sz = 512 * 1024; - break; - - case 8192 << 5: - tsb_reg = 0x5UL; - page_sz = 512 * 1024; - break; - - case 8192 << 6: - tsb_reg = 0x6UL; - page_sz = 512 * 1024; - break; - - case 8192 << 7: - tsb_reg = 0x7UL; - page_sz = 4 * 1024 * 1024; - break; - - default: - printk(KERN_ERR "TSB[%s:%d]: Impossible TSB size %lu, killing process.\n", - current->comm, current->pid, tsb_bytes); - do_exit(SIGSEGV); - }; - tte |= pte_sz_bits(page_sz); - - if (tlb_type == cheetah_plus || tlb_type == hypervisor) { - /* Physical mapping, no locked TLB entry for TSB. */ - tsb_reg |= tsb_paddr; - - mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg; - mm->context.tsb_block[tsb_idx].tsb_map_vaddr = 0; - mm->context.tsb_block[tsb_idx].tsb_map_pte = 0; - } else { - tsb_reg |= base; - tsb_reg |= (tsb_paddr & (page_sz - 1UL)); - tte |= (tsb_paddr & ~(page_sz - 1UL)); - - mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg; - mm->context.tsb_block[tsb_idx].tsb_map_vaddr = base; - mm->context.tsb_block[tsb_idx].tsb_map_pte = tte; - } - - /* Setup the Hypervisor TSB descriptor. */ - if (tlb_type == hypervisor) { - struct hv_tsb_descr *hp = &mm->context.tsb_descr[tsb_idx]; - - switch (tsb_idx) { - case MM_TSB_BASE: - hp->pgsz_idx = HV_PGSZ_IDX_BASE; - break; -#ifdef CONFIG_HUGETLB_PAGE - case MM_TSB_HUGE: - hp->pgsz_idx = HV_PGSZ_IDX_HUGE; - break; -#endif - default: - BUG(); - }; - hp->assoc = 1; - hp->num_ttes = tsb_bytes / 16; - hp->ctx_idx = 0; - switch (tsb_idx) { - case MM_TSB_BASE: - hp->pgsz_mask = HV_PGSZ_MASK_BASE; - break; -#ifdef CONFIG_HUGETLB_PAGE - case MM_TSB_HUGE: - hp->pgsz_mask = HV_PGSZ_MASK_HUGE; - break; -#endif - default: - BUG(); - }; - hp->tsb_base = tsb_paddr; - hp->resv = 0; - } -} - -static struct kmem_cache *tsb_caches[8] __read_mostly; - -static const char *tsb_cache_names[8] = { - "tsb_8KB", - "tsb_16KB", - "tsb_32KB", - "tsb_64KB", - "tsb_128KB", - "tsb_256KB", - "tsb_512KB", - "tsb_1MB", -}; - -void __init pgtable_cache_init(void) -{ - unsigned long i; - - for (i = 0; i < 8; i++) { - unsigned long size = 8192 << i; - const char *name = tsb_cache_names[i]; - - tsb_caches[i] = kmem_cache_create(name, - size, size, - 0, NULL); - if (!tsb_caches[i]) { - prom_printf("Could not create %s cache\n", name); - prom_halt(); - } - } -} - -/* When the RSS of an address space exceeds tsb_rss_limit for a TSB, - * do_sparc64_fault() invokes this routine to try and grow it. - * - * When we reach the maximum TSB size supported, we stick ~0UL into - * tsb_rss_limit for that TSB so the grow checks in do_sparc64_fault() - * will not trigger any longer. - * - * The TSB can be anywhere from 8K to 1MB in size, in increasing powers - * of two. The TSB must be aligned to it's size, so f.e. a 512K TSB - * must be 512K aligned. It also must be physically contiguous, so we - * cannot use vmalloc(). - * - * The idea here is to grow the TSB when the RSS of the process approaches - * the number of entries that the current TSB can hold at once. Currently, - * we trigger when the RSS hits 3/4 of the TSB capacity. - */ -void tsb_grow(struct mm_struct *mm, unsigned long tsb_index, unsigned long rss) -{ - unsigned long max_tsb_size = 1 * 1024 * 1024; - unsigned long new_size, old_size, flags; - struct tsb *old_tsb, *new_tsb; - unsigned long new_cache_index, old_cache_index; - unsigned long new_rss_limit; - gfp_t gfp_flags; - - if (max_tsb_size > (PAGE_SIZE << MAX_ORDER)) - max_tsb_size = (PAGE_SIZE << MAX_ORDER); - - new_cache_index = 0; - for (new_size = 8192; new_size < max_tsb_size; new_size <<= 1UL) { - unsigned long n_entries = new_size / sizeof(struct tsb); - - n_entries = (n_entries * 3) / 4; - if (n_entries > rss) - break; - - new_cache_index++; - } - - if (new_size == max_tsb_size) - new_rss_limit = ~0UL; - else - new_rss_limit = ((new_size / sizeof(struct tsb)) * 3) / 4; - -retry_tsb_alloc: - gfp_flags = GFP_KERNEL; - if (new_size > (PAGE_SIZE * 2)) - gfp_flags = __GFP_NOWARN | __GFP_NORETRY; - - new_tsb = kmem_cache_alloc_node(tsb_caches[new_cache_index], - gfp_flags, numa_node_id()); - if (unlikely(!new_tsb)) { - /* Not being able to fork due to a high-order TSB - * allocation failure is very bad behavior. Just back - * down to a 0-order allocation and force no TSB - * growing for this address space. - */ - if (mm->context.tsb_block[tsb_index].tsb == NULL && - new_cache_index > 0) { - new_cache_index = 0; - new_size = 8192; - new_rss_limit = ~0UL; - goto retry_tsb_alloc; - } - - /* If we failed on a TSB grow, we are under serious - * memory pressure so don't try to grow any more. - */ - if (mm->context.tsb_block[tsb_index].tsb != NULL) - mm->context.tsb_block[tsb_index].tsb_rss_limit = ~0UL; - return; - } - - /* Mark all tags as invalid. */ - tsb_init(new_tsb, new_size); - - /* Ok, we are about to commit the changes. If we are - * growing an existing TSB the locking is very tricky, - * so WATCH OUT! - * - * We have to hold mm->context.lock while committing to the - * new TSB, this synchronizes us with processors in - * flush_tsb_user() and switch_mm() for this address space. - * - * But even with that lock held, processors run asynchronously - * accessing the old TSB via TLB miss handling. This is OK - * because those actions are just propagating state from the - * Linux page tables into the TSB, page table mappings are not - * being changed. If a real fault occurs, the processor will - * synchronize with us when it hits flush_tsb_user(), this is - * also true for the case where vmscan is modifying the page - * tables. The only thing we need to be careful with is to - * skip any locked TSB entries during copy_tsb(). - * - * When we finish committing to the new TSB, we have to drop - * the lock and ask all other cpus running this address space - * to run tsb_context_switch() to see the new TSB table. - */ - spin_lock_irqsave(&mm->context.lock, flags); - - old_tsb = mm->context.tsb_block[tsb_index].tsb; - old_cache_index = - (mm->context.tsb_block[tsb_index].tsb_reg_val & 0x7UL); - old_size = (mm->context.tsb_block[tsb_index].tsb_nentries * - sizeof(struct tsb)); - - - /* Handle multiple threads trying to grow the TSB at the same time. - * One will get in here first, and bump the size and the RSS limit. - * The others will get in here next and hit this check. - */ - if (unlikely(old_tsb && - (rss < mm->context.tsb_block[tsb_index].tsb_rss_limit))) { - spin_unlock_irqrestore(&mm->context.lock, flags); - - kmem_cache_free(tsb_caches[new_cache_index], new_tsb); - return; - } - - mm->context.tsb_block[tsb_index].tsb_rss_limit = new_rss_limit; - - if (old_tsb) { - extern void copy_tsb(unsigned long old_tsb_base, - unsigned long old_tsb_size, - unsigned long new_tsb_base, - unsigned long new_tsb_size); - unsigned long old_tsb_base = (unsigned long) old_tsb; - unsigned long new_tsb_base = (unsigned long) new_tsb; - - if (tlb_type == cheetah_plus || tlb_type == hypervisor) { - old_tsb_base = __pa(old_tsb_base); - new_tsb_base = __pa(new_tsb_base); - } - copy_tsb(old_tsb_base, old_size, new_tsb_base, new_size); - } - - mm->context.tsb_block[tsb_index].tsb = new_tsb; - setup_tsb_params(mm, tsb_index, new_size); - - spin_unlock_irqrestore(&mm->context.lock, flags); - - /* If old_tsb is NULL, we're being invoked for the first time - * from init_new_context(). - */ - if (old_tsb) { - /* Reload it on the local cpu. */ - tsb_context_switch(mm); - - /* Now force other processors to do the same. */ - preempt_disable(); - smp_tsb_sync(mm); - preempt_enable(); - - /* Now it is safe to free the old tsb. */ - kmem_cache_free(tsb_caches[old_cache_index], old_tsb); - } -} - -int init_new_context(struct task_struct *tsk, struct mm_struct *mm) -{ -#ifdef CONFIG_HUGETLB_PAGE - unsigned long huge_pte_count; -#endif - unsigned int i; - - spin_lock_init(&mm->context.lock); - - mm->context.sparc64_ctx_val = 0UL; - -#ifdef CONFIG_HUGETLB_PAGE - /* We reset it to zero because the fork() page copying - * will re-increment the counters as the parent PTEs are - * copied into the child address space. - */ - huge_pte_count = mm->context.huge_pte_count; - mm->context.huge_pte_count = 0; -#endif - - /* copy_mm() copies over the parent's mm_struct before calling - * us, so we need to zero out the TSB pointer or else tsb_grow() - * will be confused and think there is an older TSB to free up. - */ - for (i = 0; i < MM_NUM_TSBS; i++) - mm->context.tsb_block[i].tsb = NULL; - - /* If this is fork, inherit the parent's TSB size. We would - * grow it to that size on the first page fault anyways. - */ - tsb_grow(mm, MM_TSB_BASE, get_mm_rss(mm)); - -#ifdef CONFIG_HUGETLB_PAGE - if (unlikely(huge_pte_count)) - tsb_grow(mm, MM_TSB_HUGE, huge_pte_count); -#endif - - if (unlikely(!mm->context.tsb_block[MM_TSB_BASE].tsb)) - return -ENOMEM; - - return 0; -} - -static void tsb_destroy_one(struct tsb_config *tp) -{ - unsigned long cache_index; - - if (!tp->tsb) - return; - cache_index = tp->tsb_reg_val & 0x7UL; - kmem_cache_free(tsb_caches[cache_index], tp->tsb); - tp->tsb = NULL; - tp->tsb_reg_val = 0UL; -} - -void destroy_context(struct mm_struct *mm) -{ - unsigned long flags, i; - - for (i = 0; i < MM_NUM_TSBS; i++) - tsb_destroy_one(&mm->context.tsb_block[i]); - - spin_lock_irqsave(&ctx_alloc_lock, flags); - - if (CTX_VALID(mm->context)) { - unsigned long nr = CTX_NRBITS(mm->context); - mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63)); - } - - spin_unlock_irqrestore(&ctx_alloc_lock, flags); -} |