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-rw-r--r--arch/tile/mm/homecache.c428
1 files changed, 0 insertions, 428 deletions
diff --git a/arch/tile/mm/homecache.c b/arch/tile/mm/homecache.c
deleted file mode 100644
index 4432f31e8479..000000000000
--- a/arch/tile/mm/homecache.c
+++ /dev/null
@@ -1,428 +0,0 @@
-/*
- * Copyright 2010 Tilera Corporation. All Rights Reserved.
- *
- * 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, version 2.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for
- * more details.
- *
- * This code maintains the "home" for each page in the system.
- */
-
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/spinlock.h>
-#include <linux/list.h>
-#include <linux/bootmem.h>
-#include <linux/rmap.h>
-#include <linux/pagemap.h>
-#include <linux/mutex.h>
-#include <linux/interrupt.h>
-#include <linux/sysctl.h>
-#include <linux/pagevec.h>
-#include <linux/ptrace.h>
-#include <linux/timex.h>
-#include <linux/cache.h>
-#include <linux/smp.h>
-#include <linux/module.h>
-#include <linux/hugetlb.h>
-
-#include <asm/page.h>
-#include <asm/sections.h>
-#include <asm/tlbflush.h>
-#include <asm/pgalloc.h>
-#include <asm/homecache.h>
-
-#include <arch/sim.h>
-
-#include "migrate.h"
-
-
-/*
- * The noallocl2 option suppresses all use of the L2 cache to cache
- * locally from a remote home.
- */
-static int __ro_after_init noallocl2;
-static int __init set_noallocl2(char *str)
-{
- noallocl2 = 1;
- return 0;
-}
-early_param("noallocl2", set_noallocl2);
-
-
-/*
- * Update the irq_stat for cpus that we are going to interrupt
- * with TLB or cache flushes. Also handle removing dataplane cpus
- * from the TLB flush set, and setting dataplane_tlb_state instead.
- */
-static void hv_flush_update(const struct cpumask *cache_cpumask,
- struct cpumask *tlb_cpumask,
- unsigned long tlb_va, unsigned long tlb_length,
- HV_Remote_ASID *asids, int asidcount)
-{
- struct cpumask mask;
- int i, cpu;
-
- cpumask_clear(&mask);
- if (cache_cpumask)
- cpumask_or(&mask, &mask, cache_cpumask);
- if (tlb_cpumask && tlb_length) {
- cpumask_or(&mask, &mask, tlb_cpumask);
- }
-
- for (i = 0; i < asidcount; ++i)
- cpumask_set_cpu(asids[i].y * smp_width + asids[i].x, &mask);
-
- /*
- * Don't bother to update atomically; losing a count
- * here is not that critical.
- */
- for_each_cpu(cpu, &mask)
- ++per_cpu(irq_stat, cpu).irq_hv_flush_count;
-}
-
-/*
- * This wrapper function around hv_flush_remote() does several things:
- *
- * - Provides a return value error-checking panic path, since
- * there's never any good reason for hv_flush_remote() to fail.
- * - Accepts a 32-bit PFN rather than a 64-bit PA, which generally
- * is the type that Linux wants to pass around anyway.
- * - Canonicalizes that lengths of zero make cpumasks NULL.
- * - Handles deferring TLB flushes for dataplane tiles.
- * - Tracks remote interrupts in the per-cpu irq_cpustat_t.
- *
- * Note that we have to wait until the cache flush completes before
- * updating the per-cpu last_cache_flush word, since otherwise another
- * concurrent flush can race, conclude the flush has already
- * completed, and start to use the page while it's still dirty
- * remotely (running concurrently with the actual evict, presumably).
- */
-void flush_remote(unsigned long cache_pfn, unsigned long cache_control,
- const struct cpumask *cache_cpumask_orig,
- HV_VirtAddr tlb_va, unsigned long tlb_length,
- unsigned long tlb_pgsize,
- const struct cpumask *tlb_cpumask_orig,
- HV_Remote_ASID *asids, int asidcount)
-{
- int rc;
- struct cpumask cache_cpumask_copy, tlb_cpumask_copy;
- struct cpumask *cache_cpumask, *tlb_cpumask;
- HV_PhysAddr cache_pa;
-
- mb(); /* provided just to simplify "magic hypervisor" mode */
-
- /*
- * Canonicalize and copy the cpumasks.
- */
- if (cache_cpumask_orig && cache_control) {
- cpumask_copy(&cache_cpumask_copy, cache_cpumask_orig);
- cache_cpumask = &cache_cpumask_copy;
- } else {
- cpumask_clear(&cache_cpumask_copy);
- cache_cpumask = NULL;
- }
- if (cache_cpumask == NULL)
- cache_control = 0;
- if (tlb_cpumask_orig && tlb_length) {
- cpumask_copy(&tlb_cpumask_copy, tlb_cpumask_orig);
- tlb_cpumask = &tlb_cpumask_copy;
- } else {
- cpumask_clear(&tlb_cpumask_copy);
- tlb_cpumask = NULL;
- }
-
- hv_flush_update(cache_cpumask, tlb_cpumask, tlb_va, tlb_length,
- asids, asidcount);
- cache_pa = (HV_PhysAddr)cache_pfn << PAGE_SHIFT;
- rc = hv_flush_remote(cache_pa, cache_control,
- cpumask_bits(cache_cpumask),
- tlb_va, tlb_length, tlb_pgsize,
- cpumask_bits(tlb_cpumask),
- asids, asidcount);
- if (rc == 0)
- return;
-
- pr_err("hv_flush_remote(%#llx, %#lx, %p [%*pb], %#lx, %#lx, %#lx, %p [%*pb], %p, %d) = %d\n",
- cache_pa, cache_control, cache_cpumask,
- cpumask_pr_args(&cache_cpumask_copy),
- (unsigned long)tlb_va, tlb_length, tlb_pgsize, tlb_cpumask,
- cpumask_pr_args(&tlb_cpumask_copy), asids, asidcount, rc);
- panic("Unsafe to continue.");
-}
-
-static void homecache_finv_page_va(void* va, int home)
-{
- int cpu = get_cpu();
- if (home == cpu) {
- finv_buffer_local(va, PAGE_SIZE);
- } else if (home == PAGE_HOME_HASH) {
- finv_buffer_remote(va, PAGE_SIZE, 1);
- } else {
- BUG_ON(home < 0 || home >= NR_CPUS);
- finv_buffer_remote(va, PAGE_SIZE, 0);
- }
- put_cpu();
-}
-
-void homecache_finv_map_page(struct page *page, int home)
-{
- unsigned long flags;
- unsigned long va;
- pte_t *ptep;
- pte_t pte;
-
- if (home == PAGE_HOME_UNCACHED)
- return;
- local_irq_save(flags);
-#ifdef CONFIG_HIGHMEM
- va = __fix_to_virt(FIX_KMAP_BEGIN + kmap_atomic_idx_push() +
- (KM_TYPE_NR * smp_processor_id()));
-#else
- va = __fix_to_virt(FIX_HOMECACHE_BEGIN + smp_processor_id());
-#endif
- ptep = virt_to_kpte(va);
- pte = pfn_pte(page_to_pfn(page), PAGE_KERNEL);
- __set_pte(ptep, pte_set_home(pte, home));
- homecache_finv_page_va((void *)va, home);
- __pte_clear(ptep);
- hv_flush_page(va, PAGE_SIZE);
-#ifdef CONFIG_HIGHMEM
- kmap_atomic_idx_pop();
-#endif
- local_irq_restore(flags);
-}
-
-static void homecache_finv_page_home(struct page *page, int home)
-{
- if (!PageHighMem(page) && home == page_home(page))
- homecache_finv_page_va(page_address(page), home);
- else
- homecache_finv_map_page(page, home);
-}
-
-static inline bool incoherent_home(int home)
-{
- return home == PAGE_HOME_IMMUTABLE || home == PAGE_HOME_INCOHERENT;
-}
-
-static void homecache_finv_page_internal(struct page *page, int force_map)
-{
- int home = page_home(page);
- if (home == PAGE_HOME_UNCACHED)
- return;
- if (incoherent_home(home)) {
- int cpu;
- for_each_cpu(cpu, &cpu_cacheable_map)
- homecache_finv_map_page(page, cpu);
- } else if (force_map) {
- /* Force if, e.g., the normal mapping is migrating. */
- homecache_finv_map_page(page, home);
- } else {
- homecache_finv_page_home(page, home);
- }
- sim_validate_lines_evicted(PFN_PHYS(page_to_pfn(page)), PAGE_SIZE);
-}
-
-void homecache_finv_page(struct page *page)
-{
- homecache_finv_page_internal(page, 0);
-}
-
-void homecache_evict(const struct cpumask *mask)
-{
- flush_remote(0, HV_FLUSH_EVICT_L2, mask, 0, 0, 0, NULL, NULL, 0);
-}
-
-/* Report the home corresponding to a given PTE. */
-static int pte_to_home(pte_t pte)
-{
- if (hv_pte_get_nc(pte))
- return PAGE_HOME_IMMUTABLE;
- switch (hv_pte_get_mode(pte)) {
- case HV_PTE_MODE_CACHE_TILE_L3:
- return get_remote_cache_cpu(pte);
- case HV_PTE_MODE_CACHE_NO_L3:
- return PAGE_HOME_INCOHERENT;
- case HV_PTE_MODE_UNCACHED:
- return PAGE_HOME_UNCACHED;
- case HV_PTE_MODE_CACHE_HASH_L3:
- return PAGE_HOME_HASH;
- }
- panic("Bad PTE %#llx\n", pte.val);
-}
-
-/* Update the home of a PTE if necessary (can also be used for a pgprot_t). */
-pte_t pte_set_home(pte_t pte, int home)
-{
-#if CHIP_HAS_MMIO()
- /* Check for MMIO mappings and pass them through. */
- if (hv_pte_get_mode(pte) == HV_PTE_MODE_MMIO)
- return pte;
-#endif
-
-
- /*
- * Only immutable pages get NC mappings. If we have a
- * non-coherent PTE, but the underlying page is not
- * immutable, it's likely the result of a forced
- * caching setting running up against ptrace setting
- * the page to be writable underneath. In this case,
- * just keep the PTE coherent.
- */
- if (hv_pte_get_nc(pte) && home != PAGE_HOME_IMMUTABLE) {
- pte = hv_pte_clear_nc(pte);
- pr_err("non-immutable page incoherently referenced: %#llx\n",
- pte.val);
- }
-
- switch (home) {
-
- case PAGE_HOME_UNCACHED:
- pte = hv_pte_set_mode(pte, HV_PTE_MODE_UNCACHED);
- break;
-
- case PAGE_HOME_INCOHERENT:
- pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_NO_L3);
- break;
-
- case PAGE_HOME_IMMUTABLE:
- /*
- * We could home this page anywhere, since it's immutable,
- * but by default just home it to follow "hash_default".
- */
- BUG_ON(hv_pte_get_writable(pte));
- if (pte_get_forcecache(pte)) {
- /* Upgrade "force any cpu" to "No L3" for immutable. */
- if (hv_pte_get_mode(pte) == HV_PTE_MODE_CACHE_TILE_L3
- && pte_get_anyhome(pte)) {
- pte = hv_pte_set_mode(pte,
- HV_PTE_MODE_CACHE_NO_L3);
- }
- } else
- if (hash_default)
- pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_HASH_L3);
- else
- pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_NO_L3);
- pte = hv_pte_set_nc(pte);
- break;
-
- case PAGE_HOME_HASH:
- pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_HASH_L3);
- break;
-
- default:
- BUG_ON(home < 0 || home >= NR_CPUS ||
- !cpu_is_valid_lotar(home));
- pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_TILE_L3);
- pte = set_remote_cache_cpu(pte, home);
- break;
- }
-
- if (noallocl2)
- pte = hv_pte_set_no_alloc_l2(pte);
-
- /* Simplify "no local and no l3" to "uncached" */
- if (hv_pte_get_no_alloc_l2(pte) && hv_pte_get_no_alloc_l1(pte) &&
- hv_pte_get_mode(pte) == HV_PTE_MODE_CACHE_NO_L3) {
- pte = hv_pte_set_mode(pte, HV_PTE_MODE_UNCACHED);
- }
-
- /* Checking this case here gives a better panic than from the hv. */
- BUG_ON(hv_pte_get_mode(pte) == 0);
-
- return pte;
-}
-EXPORT_SYMBOL(pte_set_home);
-
-/*
- * The routines in this section are the "static" versions of the normal
- * dynamic homecaching routines; they just set the home cache
- * of a kernel page once, and require a full-chip cache/TLB flush,
- * so they're not suitable for anything but infrequent use.
- */
-
-int page_home(struct page *page)
-{
- if (PageHighMem(page)) {
- return PAGE_HOME_HASH;
- } else {
- unsigned long kva = (unsigned long)page_address(page);
- return pte_to_home(*virt_to_kpte(kva));
- }
-}
-EXPORT_SYMBOL(page_home);
-
-void homecache_change_page_home(struct page *page, int order, int home)
-{
- int i, pages = (1 << order);
- unsigned long kva;
-
- BUG_ON(PageHighMem(page));
- BUG_ON(page_count(page) > 1);
- BUG_ON(page_mapcount(page) != 0);
- kva = (unsigned long) page_address(page);
- flush_remote(0, HV_FLUSH_EVICT_L2, &cpu_cacheable_map,
- kva, pages * PAGE_SIZE, PAGE_SIZE, cpu_online_mask,
- NULL, 0);
-
- for (i = 0; i < pages; ++i, kva += PAGE_SIZE) {
- pte_t *ptep = virt_to_kpte(kva);
- pte_t pteval = *ptep;
- BUG_ON(!pte_present(pteval) || pte_huge(pteval));
- __set_pte(ptep, pte_set_home(pteval, home));
- }
-}
-EXPORT_SYMBOL(homecache_change_page_home);
-
-struct page *homecache_alloc_pages(gfp_t gfp_mask,
- unsigned int order, int home)
-{
- struct page *page;
- BUG_ON(gfp_mask & __GFP_HIGHMEM); /* must be lowmem */
- page = alloc_pages(gfp_mask, order);
- if (page)
- homecache_change_page_home(page, order, home);
- return page;
-}
-EXPORT_SYMBOL(homecache_alloc_pages);
-
-struct page *homecache_alloc_pages_node(int nid, gfp_t gfp_mask,
- unsigned int order, int home)
-{
- struct page *page;
- BUG_ON(gfp_mask & __GFP_HIGHMEM); /* must be lowmem */
- page = alloc_pages_node(nid, gfp_mask, order);
- if (page)
- homecache_change_page_home(page, order, home);
- return page;
-}
-
-void __homecache_free_pages(struct page *page, unsigned int order)
-{
- if (put_page_testzero(page)) {
- homecache_change_page_home(page, order, PAGE_HOME_HASH);
- if (order == 0) {
- free_unref_page(page);
- } else {
- init_page_count(page);
- __free_pages(page, order);
- }
- }
-}
-EXPORT_SYMBOL(__homecache_free_pages);
-
-void homecache_free_pages(unsigned long addr, unsigned int order)
-{
- if (addr != 0) {
- VM_BUG_ON(!virt_addr_valid((void *)addr));
- __homecache_free_pages(virt_to_page((void *)addr), order);
- }
-}
-EXPORT_SYMBOL(homecache_free_pages);