If in doubt, say Y.
+config HIGHMEM
+ bool "High Memory Support"
+ help
+ Linux can use the full amount of RAM in the system by
+ default. However, the default MMUv2 setup only maps the
+ lowermost 128 MB of memory linearly to the areas starting
+ at 0xd0000000 (cached) and 0xd8000000 (uncached).
+ When there are more than 128 MB memory in the system not
+ all of it can be "permanently mapped" by the kernel.
+ The physical memory that's not permanently mapped is called
+ "high memory".
+
+ If you are compiling a kernel which will never run on a
+ machine with more than 128 MB total physical RAM, answer
+ N here.
+
+ If unsure, say Y.
+
endmenu
config XTENSA_CALIBRATE_CCOUNT
--- /dev/null
+/*
+ * fixmap.h: compile-time virtual memory allocation
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1998 Ingo Molnar
+ *
+ * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
+ */
+
+#ifndef _ASM_FIXMAP_H
+#define _ASM_FIXMAP_H
+
+#include <asm/pgtable.h>
+#ifdef CONFIG_HIGHMEM
+#include <linux/threads.h>
+#include <asm/kmap_types.h>
+#endif
+
+/*
+ * Here we define all the compile-time 'special' virtual
+ * addresses. The point is to have a constant address at
+ * compile time, but to set the physical address only
+ * in the boot process. We allocate these special addresses
+ * from the end of the consistent memory region backwards.
+ * Also this lets us do fail-safe vmalloc(), we
+ * can guarantee that these special addresses and
+ * vmalloc()-ed addresses never overlap.
+ *
+ * these 'compile-time allocated' memory buffers are
+ * fixed-size 4k pages. (or larger if used with an increment
+ * higher than 1) use fixmap_set(idx,phys) to associate
+ * physical memory with fixmap indices.
+ */
+enum fixed_addresses {
+#ifdef CONFIG_HIGHMEM
+ /* reserved pte's for temporary kernel mappings */
+ FIX_KMAP_BEGIN,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+#endif
+ __end_of_fixed_addresses
+};
+
+#define FIXADDR_TOP (VMALLOC_START - PAGE_SIZE)
+#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
+#define FIXADDR_START ((FIXADDR_TOP - FIXADDR_SIZE) & PMD_MASK)
+
+#include <asm-generic/fixmap.h>
+
+#define kmap_get_fixmap_pte(vaddr) \
+ pte_offset_kernel( \
+ pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), \
+ (vaddr) \
+ )
+
+#endif
* this archive for more details.
*
* Copyright (C) 2003 - 2005 Tensilica Inc.
+ * Copyright (C) 2014 Cadence Design Systems Inc.
*/
#ifndef _XTENSA_HIGHMEM_H
#define _XTENSA_HIGHMEM_H
-extern void flush_cache_kmaps(void);
+#include <asm/cacheflush.h>
+#include <asm/fixmap.h>
+#include <asm/kmap_types.h>
+#include <asm/pgtable.h>
+
+#define PKMAP_BASE (FIXADDR_START - PMD_SIZE)
+#define LAST_PKMAP PTRS_PER_PTE
+#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
+#define PKMAP_NR(virt) (((virt) - PKMAP_BASE) >> PAGE_SHIFT)
+#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
+
+#define kmap_prot PAGE_KERNEL
+
+extern pte_t *pkmap_page_table;
+
+void *kmap_high(struct page *page);
+void kunmap_high(struct page *page);
+
+static inline void *kmap(struct page *page)
+{
+ BUG_ON(in_interrupt());
+ if (!PageHighMem(page))
+ return page_address(page);
+ return kmap_high(page);
+}
+
+static inline void kunmap(struct page *page)
+{
+ BUG_ON(in_interrupt());
+ if (!PageHighMem(page))
+ return;
+ kunmap_high(page);
+}
+
+static inline void flush_cache_kmaps(void)
+{
+ flush_cache_all();
+}
+
+void *kmap_atomic(struct page *page);
+void __kunmap_atomic(void *kvaddr);
+
+void kmap_init(void);
#endif
update_pte(ptep, pteval);
}
+static inline void set_pte(pte_t *ptep, pte_t pteval)
+{
+ update_pte(ptep, pteval);
+}
static inline void
set_pmd(pmd_t *pmdp, pmd_t pmdval)
obj-y := init.o cache.o misc.o
obj-$(CONFIG_MMU) += fault.o mmu.o tlb.o
+obj-$(CONFIG_HIGHMEM) += highmem.o
*
*/
+#if (DCACHE_WAY_SIZE > PAGE_SIZE) && defined(CONFIG_HIGHMEM)
+#error "HIGHMEM is not supported on cores with aliasing cache."
+#endif
+
#if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK
/*
#else
if (!PageReserved(page) && !test_bit(PG_arch_1, &page->flags)
&& (vma->vm_flags & VM_EXEC) != 0) {
- unsigned long paddr = (unsigned long) page_address(page);
+ unsigned long paddr = (unsigned long)kmap_atomic(page);
__flush_dcache_page(paddr);
__invalidate_icache_page(paddr);
set_bit(PG_arch_1, &page->flags);
+ kunmap_atomic((void *)paddr);
}
#endif
}
--- /dev/null
+/*
+ * High memory support for Xtensa architecture
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of
+ * this archive for more details.
+ *
+ * Copyright (C) 2014 Cadence Design Systems Inc.
+ */
+
+#include <linux/export.h>
+#include <linux/highmem.h>
+#include <asm/tlbflush.h>
+
+static pte_t *kmap_pte;
+
+void *kmap_atomic(struct page *page)
+{
+ enum fixed_addresses idx;
+ unsigned long vaddr;
+ int type;
+
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+
+ type = kmap_atomic_idx_push();
+ idx = type + KM_TYPE_NR * smp_processor_id();
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(!pte_none(*(kmap_pte - idx)));
+#endif
+ set_pte(kmap_pte - idx, mk_pte(page, PAGE_KERNEL_EXEC));
+
+ return (void *)vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+ int idx, type;
+
+ if (kvaddr >= (void *)FIXADDR_START &&
+ kvaddr < (void *)FIXADDR_TOP) {
+ type = kmap_atomic_idx();
+ idx = type + KM_TYPE_NR * smp_processor_id();
+
+ /*
+ * Force other mappings to Oops if they'll try to access this
+ * pte without first remap it. Keeping stale mappings around
+ * is a bad idea also, in case the page changes cacheability
+ * attributes or becomes a protected page in a hypervisor.
+ */
+ pte_clear(&init_mm, kvaddr, kmap_pte - idx);
+ local_flush_tlb_kernel_range((unsigned long)kvaddr,
+ (unsigned long)kvaddr + PAGE_SIZE);
+
+ kmap_atomic_idx_pop();
+ }
+
+ pagefault_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);
+
+void __init kmap_init(void)
+{
+ unsigned long kmap_vstart;
+
+ /* cache the first kmap pte */
+ kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
+ kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
+}
#include <linux/errno.h>
#include <linux/bootmem.h>
#include <linux/gfp.h>
+#include <linux/highmem.h>
#include <linux/swap.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
void __init zones_init(void)
{
- unsigned long zones_size[MAX_NR_ZONES];
- int i;
-
/* All pages are DMA-able, so we put them all in the DMA zone. */
-
- zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET;
- for (i = 1; i < MAX_NR_ZONES; i++)
- zones_size[i] = 0;
-
+ unsigned long zones_size[MAX_NR_ZONES] = {
+ [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET,
#ifdef CONFIG_HIGHMEM
- zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
+ [ZONE_HIGHMEM] = max_pfn - max_low_pfn,
#endif
-
+ };
free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
}
void __init mem_init(void)
{
- max_mapnr = max_low_pfn - ARCH_PFN_OFFSET;
- high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
-
#ifdef CONFIG_HIGHMEM
-#error HIGHGMEM not implemented in init.c
+ unsigned long tmp;
+
+ reset_all_zones_managed_pages();
+ for (tmp = max_low_pfn; tmp < max_pfn; tmp++)
+ free_highmem_page(pfn_to_page(tmp));
#endif
+ max_mapnr = max_pfn - ARCH_PFN_OFFSET;
+ high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT);
+
free_all_bootmem();
mem_init_print_info(NULL);
+ pr_info("virtual kernel memory layout:\n"
+#ifdef CONFIG_HIGHMEM
+ " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
+ " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
+#endif
+ " vmalloc : 0x%08x - 0x%08x (%5u MB)\n"
+ " lowmem : 0x%08x - 0x%08lx (%5lu MB)\n",
+#ifdef CONFIG_HIGHMEM
+ PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
+ (LAST_PKMAP*PAGE_SIZE) >> 10,
+ FIXADDR_START, FIXADDR_TOP,
+ (FIXADDR_TOP - FIXADDR_START) >> 10,
+#endif
+ VMALLOC_START, VMALLOC_END,
+ (VMALLOC_END - VMALLOC_START) >> 20,
+ PAGE_OFFSET, PAGE_OFFSET +
+ (max_low_pfn - min_low_pfn) * PAGE_SIZE,
+ ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20);
}
#ifdef CONFIG_BLK_DEV_INITRD
*
* Extracted from init.c
*/
+#include <linux/bootmem.h>
#include <linux/percpu.h>
#include <linux/init.h>
#include <linux/string.h>
#include <asm/initialize_mmu.h>
#include <asm/io.h>
+#if defined(CONFIG_HIGHMEM)
+static void * __init init_pmd(unsigned long vaddr)
+{
+ pgd_t *pgd = pgd_offset_k(vaddr);
+ pmd_t *pmd = pmd_offset(pgd, vaddr);
+
+ if (pmd_none(*pmd)) {
+ unsigned i;
+ pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE);
+
+ for (i = 0; i < 1024; i++)
+ pte_clear(NULL, 0, pte + i);
+
+ set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK));
+ BUG_ON(pte != pte_offset_kernel(pmd, 0));
+ pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n",
+ __func__, vaddr, pmd, pte);
+ return pte;
+ } else {
+ return pte_offset_kernel(pmd, 0);
+ }
+}
+
+static void __init fixedrange_init(void)
+{
+ BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE);
+ init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK);
+}
+#endif
+
void __init paging_init(void)
{
memset(swapper_pg_dir, 0, PAGE_SIZE);
+#ifdef CONFIG_HIGHMEM
+ fixedrange_init();
+ pkmap_page_table = init_pmd(PKMAP_BASE);
+ kmap_init();
+#endif
}
/*
projects / firefly-linux-kernel-4.4.55.git / commitdiff