cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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cache.c (9602B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * arch/sh/mm/cache.c
      4 *
      5 * Copyright (C) 1999, 2000, 2002  Niibe Yutaka
      6 * Copyright (C) 2002 - 2010  Paul Mundt
      7 */
      8#include <linux/mm.h>
      9#include <linux/init.h>
     10#include <linux/mutex.h>
     11#include <linux/fs.h>
     12#include <linux/smp.h>
     13#include <linux/highmem.h>
     14#include <linux/module.h>
     15#include <asm/mmu_context.h>
     16#include <asm/cacheflush.h>
     17
     18void (*local_flush_cache_all)(void *args) = cache_noop;
     19void (*local_flush_cache_mm)(void *args) = cache_noop;
     20void (*local_flush_cache_dup_mm)(void *args) = cache_noop;
     21void (*local_flush_cache_page)(void *args) = cache_noop;
     22void (*local_flush_cache_range)(void *args) = cache_noop;
     23void (*local_flush_dcache_page)(void *args) = cache_noop;
     24void (*local_flush_icache_range)(void *args) = cache_noop;
     25void (*local_flush_icache_page)(void *args) = cache_noop;
     26void (*local_flush_cache_sigtramp)(void *args) = cache_noop;
     27
     28void (*__flush_wback_region)(void *start, int size);
     29EXPORT_SYMBOL(__flush_wback_region);
     30void (*__flush_purge_region)(void *start, int size);
     31EXPORT_SYMBOL(__flush_purge_region);
     32void (*__flush_invalidate_region)(void *start, int size);
     33EXPORT_SYMBOL(__flush_invalidate_region);
     34
     35static inline void noop__flush_region(void *start, int size)
     36{
     37}
     38
     39static inline void cacheop_on_each_cpu(void (*func) (void *info), void *info,
     40                                   int wait)
     41{
     42	preempt_disable();
     43
     44	/* Needing IPI for cross-core flush is SHX3-specific. */
     45#ifdef CONFIG_CPU_SHX3
     46	/*
     47	 * It's possible that this gets called early on when IRQs are
     48	 * still disabled due to ioremapping by the boot CPU, so don't
     49	 * even attempt IPIs unless there are other CPUs online.
     50	 */
     51	if (num_online_cpus() > 1)
     52		smp_call_function(func, info, wait);
     53#endif
     54
     55	func(info);
     56
     57	preempt_enable();
     58}
     59
     60void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
     61		       unsigned long vaddr, void *dst, const void *src,
     62		       unsigned long len)
     63{
     64	if (boot_cpu_data.dcache.n_aliases && page_mapcount(page) &&
     65	    test_bit(PG_dcache_clean, &page->flags)) {
     66		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
     67		memcpy(vto, src, len);
     68		kunmap_coherent(vto);
     69	} else {
     70		memcpy(dst, src, len);
     71		if (boot_cpu_data.dcache.n_aliases)
     72			clear_bit(PG_dcache_clean, &page->flags);
     73	}
     74
     75	if (vma->vm_flags & VM_EXEC)
     76		flush_cache_page(vma, vaddr, page_to_pfn(page));
     77}
     78
     79void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
     80			 unsigned long vaddr, void *dst, const void *src,
     81			 unsigned long len)
     82{
     83	if (boot_cpu_data.dcache.n_aliases && page_mapcount(page) &&
     84	    test_bit(PG_dcache_clean, &page->flags)) {
     85		void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
     86		memcpy(dst, vfrom, len);
     87		kunmap_coherent(vfrom);
     88	} else {
     89		memcpy(dst, src, len);
     90		if (boot_cpu_data.dcache.n_aliases)
     91			clear_bit(PG_dcache_clean, &page->flags);
     92	}
     93}
     94
     95void copy_user_highpage(struct page *to, struct page *from,
     96			unsigned long vaddr, struct vm_area_struct *vma)
     97{
     98	void *vfrom, *vto;
     99
    100	vto = kmap_atomic(to);
    101
    102	if (boot_cpu_data.dcache.n_aliases && page_mapcount(from) &&
    103	    test_bit(PG_dcache_clean, &from->flags)) {
    104		vfrom = kmap_coherent(from, vaddr);
    105		copy_page(vto, vfrom);
    106		kunmap_coherent(vfrom);
    107	} else {
    108		vfrom = kmap_atomic(from);
    109		copy_page(vto, vfrom);
    110		kunmap_atomic(vfrom);
    111	}
    112
    113	if (pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK) ||
    114	    (vma->vm_flags & VM_EXEC))
    115		__flush_purge_region(vto, PAGE_SIZE);
    116
    117	kunmap_atomic(vto);
    118	/* Make sure this page is cleared on other CPU's too before using it */
    119	smp_wmb();
    120}
    121EXPORT_SYMBOL(copy_user_highpage);
    122
    123void clear_user_highpage(struct page *page, unsigned long vaddr)
    124{
    125	void *kaddr = kmap_atomic(page);
    126
    127	clear_page(kaddr);
    128
    129	if (pages_do_alias((unsigned long)kaddr, vaddr & PAGE_MASK))
    130		__flush_purge_region(kaddr, PAGE_SIZE);
    131
    132	kunmap_atomic(kaddr);
    133}
    134EXPORT_SYMBOL(clear_user_highpage);
    135
    136void __update_cache(struct vm_area_struct *vma,
    137		    unsigned long address, pte_t pte)
    138{
    139	struct page *page;
    140	unsigned long pfn = pte_pfn(pte);
    141
    142	if (!boot_cpu_data.dcache.n_aliases)
    143		return;
    144
    145	page = pfn_to_page(pfn);
    146	if (pfn_valid(pfn)) {
    147		int dirty = !test_and_set_bit(PG_dcache_clean, &page->flags);
    148		if (dirty)
    149			__flush_purge_region(page_address(page), PAGE_SIZE);
    150	}
    151}
    152
    153void __flush_anon_page(struct page *page, unsigned long vmaddr)
    154{
    155	unsigned long addr = (unsigned long) page_address(page);
    156
    157	if (pages_do_alias(addr, vmaddr)) {
    158		if (boot_cpu_data.dcache.n_aliases && page_mapcount(page) &&
    159		    test_bit(PG_dcache_clean, &page->flags)) {
    160			void *kaddr;
    161
    162			kaddr = kmap_coherent(page, vmaddr);
    163			/* XXX.. For now kunmap_coherent() does a purge */
    164			/* __flush_purge_region((void *)kaddr, PAGE_SIZE); */
    165			kunmap_coherent(kaddr);
    166		} else
    167			__flush_purge_region((void *)addr, PAGE_SIZE);
    168	}
    169}
    170
    171void flush_cache_all(void)
    172{
    173	cacheop_on_each_cpu(local_flush_cache_all, NULL, 1);
    174}
    175EXPORT_SYMBOL(flush_cache_all);
    176
    177void flush_cache_mm(struct mm_struct *mm)
    178{
    179	if (boot_cpu_data.dcache.n_aliases == 0)
    180		return;
    181
    182	cacheop_on_each_cpu(local_flush_cache_mm, mm, 1);
    183}
    184
    185void flush_cache_dup_mm(struct mm_struct *mm)
    186{
    187	if (boot_cpu_data.dcache.n_aliases == 0)
    188		return;
    189
    190	cacheop_on_each_cpu(local_flush_cache_dup_mm, mm, 1);
    191}
    192
    193void flush_cache_page(struct vm_area_struct *vma, unsigned long addr,
    194		      unsigned long pfn)
    195{
    196	struct flusher_data data;
    197
    198	data.vma = vma;
    199	data.addr1 = addr;
    200	data.addr2 = pfn;
    201
    202	cacheop_on_each_cpu(local_flush_cache_page, (void *)&data, 1);
    203}
    204
    205void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
    206		       unsigned long end)
    207{
    208	struct flusher_data data;
    209
    210	data.vma = vma;
    211	data.addr1 = start;
    212	data.addr2 = end;
    213
    214	cacheop_on_each_cpu(local_flush_cache_range, (void *)&data, 1);
    215}
    216EXPORT_SYMBOL(flush_cache_range);
    217
    218void flush_dcache_page(struct page *page)
    219{
    220	cacheop_on_each_cpu(local_flush_dcache_page, page, 1);
    221}
    222EXPORT_SYMBOL(flush_dcache_page);
    223
    224void flush_icache_range(unsigned long start, unsigned long end)
    225{
    226	struct flusher_data data;
    227
    228	data.vma = NULL;
    229	data.addr1 = start;
    230	data.addr2 = end;
    231
    232	cacheop_on_each_cpu(local_flush_icache_range, (void *)&data, 1);
    233}
    234EXPORT_SYMBOL(flush_icache_range);
    235
    236void flush_icache_page(struct vm_area_struct *vma, struct page *page)
    237{
    238	/* Nothing uses the VMA, so just pass the struct page along */
    239	cacheop_on_each_cpu(local_flush_icache_page, page, 1);
    240}
    241
    242void flush_cache_sigtramp(unsigned long address)
    243{
    244	cacheop_on_each_cpu(local_flush_cache_sigtramp, (void *)address, 1);
    245}
    246
    247static void compute_alias(struct cache_info *c)
    248{
    249#ifdef CONFIG_MMU
    250	c->alias_mask = ((c->sets - 1) << c->entry_shift) & ~(PAGE_SIZE - 1);
    251#else
    252	c->alias_mask = 0;
    253#endif
    254	c->n_aliases = c->alias_mask ? (c->alias_mask >> PAGE_SHIFT) + 1 : 0;
    255}
    256
    257static void __init emit_cache_params(void)
    258{
    259	printk(KERN_NOTICE "I-cache : n_ways=%d n_sets=%d way_incr=%d\n",
    260		boot_cpu_data.icache.ways,
    261		boot_cpu_data.icache.sets,
    262		boot_cpu_data.icache.way_incr);
    263	printk(KERN_NOTICE "I-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
    264		boot_cpu_data.icache.entry_mask,
    265		boot_cpu_data.icache.alias_mask,
    266		boot_cpu_data.icache.n_aliases);
    267	printk(KERN_NOTICE "D-cache : n_ways=%d n_sets=%d way_incr=%d\n",
    268		boot_cpu_data.dcache.ways,
    269		boot_cpu_data.dcache.sets,
    270		boot_cpu_data.dcache.way_incr);
    271	printk(KERN_NOTICE "D-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
    272		boot_cpu_data.dcache.entry_mask,
    273		boot_cpu_data.dcache.alias_mask,
    274		boot_cpu_data.dcache.n_aliases);
    275
    276	/*
    277	 * Emit Secondary Cache parameters if the CPU has a probed L2.
    278	 */
    279	if (boot_cpu_data.flags & CPU_HAS_L2_CACHE) {
    280		printk(KERN_NOTICE "S-cache : n_ways=%d n_sets=%d way_incr=%d\n",
    281			boot_cpu_data.scache.ways,
    282			boot_cpu_data.scache.sets,
    283			boot_cpu_data.scache.way_incr);
    284		printk(KERN_NOTICE "S-cache : entry_mask=0x%08x alias_mask=0x%08x n_aliases=%d\n",
    285			boot_cpu_data.scache.entry_mask,
    286			boot_cpu_data.scache.alias_mask,
    287			boot_cpu_data.scache.n_aliases);
    288	}
    289}
    290
    291void __init cpu_cache_init(void)
    292{
    293	unsigned int cache_disabled = 0;
    294
    295#ifdef SH_CCR
    296	cache_disabled = !(__raw_readl(SH_CCR) & CCR_CACHE_ENABLE);
    297#endif
    298
    299	compute_alias(&boot_cpu_data.icache);
    300	compute_alias(&boot_cpu_data.dcache);
    301	compute_alias(&boot_cpu_data.scache);
    302
    303	__flush_wback_region		= noop__flush_region;
    304	__flush_purge_region		= noop__flush_region;
    305	__flush_invalidate_region	= noop__flush_region;
    306
    307	/*
    308	 * No flushing is necessary in the disabled cache case so we can
    309	 * just keep the noop functions in local_flush_..() and __flush_..()
    310	 */
    311	if (unlikely(cache_disabled))
    312		goto skip;
    313
    314	if (boot_cpu_data.type == CPU_J2) {
    315		extern void __weak j2_cache_init(void);
    316
    317		j2_cache_init();
    318	} else if (boot_cpu_data.family == CPU_FAMILY_SH2) {
    319		extern void __weak sh2_cache_init(void);
    320
    321		sh2_cache_init();
    322	}
    323
    324	if (boot_cpu_data.family == CPU_FAMILY_SH2A) {
    325		extern void __weak sh2a_cache_init(void);
    326
    327		sh2a_cache_init();
    328	}
    329
    330	if (boot_cpu_data.family == CPU_FAMILY_SH3) {
    331		extern void __weak sh3_cache_init(void);
    332
    333		sh3_cache_init();
    334
    335		if ((boot_cpu_data.type == CPU_SH7705) &&
    336		    (boot_cpu_data.dcache.sets == 512)) {
    337			extern void __weak sh7705_cache_init(void);
    338
    339			sh7705_cache_init();
    340		}
    341	}
    342
    343	if ((boot_cpu_data.family == CPU_FAMILY_SH4) ||
    344	    (boot_cpu_data.family == CPU_FAMILY_SH4A) ||
    345	    (boot_cpu_data.family == CPU_FAMILY_SH4AL_DSP)) {
    346		extern void __weak sh4_cache_init(void);
    347
    348		sh4_cache_init();
    349
    350		if ((boot_cpu_data.type == CPU_SH7786) ||
    351		    (boot_cpu_data.type == CPU_SHX3)) {
    352			extern void __weak shx3_cache_init(void);
    353
    354			shx3_cache_init();
    355		}
    356	}
    357
    358skip:
    359	emit_cache_params();
    360}