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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/x86/mm/init.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'arch/x86/mm/init.c')
-rw-r--r--arch/x86/mm/init.c416
1 files changed, 416 insertions, 0 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
new file mode 100644
index 00000000..4f0cec7e
--- /dev/null
+++ b/arch/x86/mm/init.c
@@ -0,0 +1,416 @@
+#include <linux/gfp.h>
+#include <linux/initrd.h>
+#include <linux/ioport.h>
+#include <linux/swap.h>
+#include <linux/memblock.h>
+#include <linux/bootmem.h> /* for max_low_pfn */
+
+#include <asm/cacheflush.h>
+#include <asm/e820.h>
+#include <asm/init.h>
+#include <asm/page.h>
+#include <asm/page_types.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/tlbflush.h>
+#include <asm/tlb.h>
+#include <asm/proto.h>
+#include <asm/dma.h> /* for MAX_DMA_PFN */
+
+unsigned long __initdata pgt_buf_start;
+unsigned long __meminitdata pgt_buf_end;
+unsigned long __meminitdata pgt_buf_top;
+
+int after_bootmem;
+
+int direct_gbpages
+#ifdef CONFIG_DIRECT_GBPAGES
+ = 1
+#endif
+;
+
+static void __init find_early_table_space(unsigned long end, int use_pse,
+ int use_gbpages)
+{
+ unsigned long puds, pmds, ptes, tables, start = 0, good_end = end;
+ phys_addr_t base;
+
+ puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
+ tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
+
+ if (use_gbpages) {
+ unsigned long extra;
+
+ extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
+ pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
+ } else
+ pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
+
+ tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
+
+ if (use_pse) {
+ unsigned long extra;
+
+ extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
+#ifdef CONFIG_X86_32
+ extra += PMD_SIZE;
+#endif
+ ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ } else
+ ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
+ tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
+
+#ifdef CONFIG_X86_32
+ /* for fixmap */
+ tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
+#endif
+ good_end = max_pfn_mapped << PAGE_SHIFT;
+
+ base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
+ if (!base)
+ panic("Cannot find space for the kernel page tables");
+
+ pgt_buf_start = base >> PAGE_SHIFT;
+ pgt_buf_end = pgt_buf_start;
+ pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
+
+ printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
+ end, pgt_buf_start << PAGE_SHIFT, pgt_buf_top << PAGE_SHIFT);
+}
+
+void __init native_pagetable_reserve(u64 start, u64 end)
+{
+ memblock_reserve(start, end - start);
+}
+
+struct map_range {
+ unsigned long start;
+ unsigned long end;
+ unsigned page_size_mask;
+};
+
+#ifdef CONFIG_X86_32
+#define NR_RANGE_MR 3
+#else /* CONFIG_X86_64 */
+#define NR_RANGE_MR 5
+#endif
+
+static int __meminit save_mr(struct map_range *mr, int nr_range,
+ unsigned long start_pfn, unsigned long end_pfn,
+ unsigned long page_size_mask)
+{
+ if (start_pfn < end_pfn) {
+ if (nr_range >= NR_RANGE_MR)
+ panic("run out of range for init_memory_mapping\n");
+ mr[nr_range].start = start_pfn<<PAGE_SHIFT;
+ mr[nr_range].end = end_pfn<<PAGE_SHIFT;
+ mr[nr_range].page_size_mask = page_size_mask;
+ nr_range++;
+ }
+
+ return nr_range;
+}
+
+/*
+ * Setup the direct mapping of the physical memory at PAGE_OFFSET.
+ * This runs before bootmem is initialized and gets pages directly from
+ * the physical memory. To access them they are temporarily mapped.
+ */
+unsigned long __init_refok init_memory_mapping(unsigned long start,
+ unsigned long end)
+{
+ unsigned long page_size_mask = 0;
+ unsigned long start_pfn, end_pfn;
+ unsigned long ret = 0;
+ unsigned long pos;
+
+ struct map_range mr[NR_RANGE_MR];
+ int nr_range, i;
+ int use_pse, use_gbpages;
+
+ printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);
+
+#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KMEMCHECK)
+ /*
+ * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
+ * This will simplify cpa(), which otherwise needs to support splitting
+ * large pages into small in interrupt context, etc.
+ */
+ use_pse = use_gbpages = 0;
+#else
+ use_pse = cpu_has_pse;
+ use_gbpages = direct_gbpages;
+#endif
+
+ /* Enable PSE if available */
+ if (cpu_has_pse)
+ set_in_cr4(X86_CR4_PSE);
+
+ /* Enable PGE if available */
+ if (cpu_has_pge) {
+ set_in_cr4(X86_CR4_PGE);
+ __supported_pte_mask |= _PAGE_GLOBAL;
+ }
+
+ if (use_gbpages)
+ page_size_mask |= 1 << PG_LEVEL_1G;
+ if (use_pse)
+ page_size_mask |= 1 << PG_LEVEL_2M;
+
+ memset(mr, 0, sizeof(mr));
+ nr_range = 0;
+
+ /* head if not big page alignment ? */
+ start_pfn = start >> PAGE_SHIFT;
+ pos = start_pfn << PAGE_SHIFT;
+#ifdef CONFIG_X86_32
+ /*
+ * Don't use a large page for the first 2/4MB of memory
+ * because there are often fixed size MTRRs in there
+ * and overlapping MTRRs into large pages can cause
+ * slowdowns.
+ */
+ if (pos == 0)
+ end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
+ else
+ end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+#else /* CONFIG_X86_64 */
+ end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+#endif
+ if (end_pfn > (end >> PAGE_SHIFT))
+ end_pfn = end >> PAGE_SHIFT;
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
+ pos = end_pfn << PAGE_SHIFT;
+ }
+
+ /* big page (2M) range */
+ start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+#ifdef CONFIG_X86_32
+ end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+#else /* CONFIG_X86_64 */
+ end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
+ << (PUD_SHIFT - PAGE_SHIFT);
+ if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
+ end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
+#endif
+
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+ page_size_mask & (1<<PG_LEVEL_2M));
+ pos = end_pfn << PAGE_SHIFT;
+ }
+
+#ifdef CONFIG_X86_64
+ /* big page (1G) range */
+ start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
+ << (PUD_SHIFT - PAGE_SHIFT);
+ end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+ page_size_mask &
+ ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
+ pos = end_pfn << PAGE_SHIFT;
+ }
+
+ /* tail is not big page (1G) alignment */
+ start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+ end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+ page_size_mask & (1<<PG_LEVEL_2M));
+ pos = end_pfn << PAGE_SHIFT;
+ }
+#endif
+
+ /* tail is not big page (2M) alignment */
+ start_pfn = pos>>PAGE_SHIFT;
+ end_pfn = end>>PAGE_SHIFT;
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
+
+ /* try to merge same page size and continuous */
+ for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
+ unsigned long old_start;
+ if (mr[i].end != mr[i+1].start ||
+ mr[i].page_size_mask != mr[i+1].page_size_mask)
+ continue;
+ /* move it */
+ old_start = mr[i].start;
+ memmove(&mr[i], &mr[i+1],
+ (nr_range - 1 - i) * sizeof(struct map_range));
+ mr[i--].start = old_start;
+ nr_range--;
+ }
+
+ for (i = 0; i < nr_range; i++)
+ printk(KERN_DEBUG " %010lx - %010lx page %s\n",
+ mr[i].start, mr[i].end,
+ (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
+ (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
+
+ /*
+ * Find space for the kernel direct mapping tables.
+ *
+ * Later we should allocate these tables in the local node of the
+ * memory mapped. Unfortunately this is done currently before the
+ * nodes are discovered.
+ */
+ if (!after_bootmem)
+ find_early_table_space(end, use_pse, use_gbpages);
+
+ for (i = 0; i < nr_range; i++)
+ ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
+ mr[i].page_size_mask);
+
+#ifdef CONFIG_X86_32
+ early_ioremap_page_table_range_init();
+
+ load_cr3(swapper_pg_dir);
+#endif
+
+ __flush_tlb_all();
+
+ /*
+ * Reserve the kernel pagetable pages we used (pgt_buf_start -
+ * pgt_buf_end) and free the other ones (pgt_buf_end - pgt_buf_top)
+ * so that they can be reused for other purposes.
+ *
+ * On native it just means calling memblock_reserve, on Xen it also
+ * means marking RW the pagetable pages that we allocated before
+ * but that haven't been used.
+ *
+ * In fact on xen we mark RO the whole range pgt_buf_start -
+ * pgt_buf_top, because we have to make sure that when
+ * init_memory_mapping reaches the pagetable pages area, it maps
+ * RO all the pagetable pages, including the ones that are beyond
+ * pgt_buf_end at that time.
+ */
+ if (!after_bootmem && pgt_buf_end > pgt_buf_start)
+ x86_init.mapping.pagetable_reserve(PFN_PHYS(pgt_buf_start),
+ PFN_PHYS(pgt_buf_end));
+
+ if (!after_bootmem)
+ early_memtest(start, end);
+
+ return ret >> PAGE_SHIFT;
+}
+
+
+/*
+ * devmem_is_allowed() checks to see if /dev/mem access to a certain address
+ * is valid. The argument is a physical page number.
+ *
+ *
+ * On x86, access has to be given to the first megabyte of ram because that area
+ * contains bios code and data regions used by X and dosemu and similar apps.
+ * Access has to be given to non-kernel-ram areas as well, these contain the PCI
+ * mmio resources as well as potential bios/acpi data regions.
+ */
+int devmem_is_allowed(unsigned long pagenr)
+{
+ if (pagenr <= 256)
+ return 1;
+ if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
+ return 0;
+ if (!page_is_ram(pagenr))
+ return 1;
+ return 0;
+}
+
+void free_init_pages(char *what, unsigned long begin, unsigned long end)
+{
+ unsigned long addr;
+ unsigned long begin_aligned, end_aligned;
+
+ /* Make sure boundaries are page aligned */
+ begin_aligned = PAGE_ALIGN(begin);
+ end_aligned = end & PAGE_MASK;
+
+ if (WARN_ON(begin_aligned != begin || end_aligned != end)) {
+ begin = begin_aligned;
+ end = end_aligned;
+ }
+
+ if (begin >= end)
+ return;
+
+ addr = begin;
+
+ /*
+ * If debugging page accesses then do not free this memory but
+ * mark them not present - any buggy init-section access will
+ * create a kernel page fault:
+ */
+#ifdef CONFIG_DEBUG_PAGEALLOC
+ printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
+ begin, end);
+ set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
+#else
+ /*
+ * We just marked the kernel text read only above, now that
+ * we are going to free part of that, we need to make that
+ * writeable and non-executable first.
+ */
+ set_memory_nx(begin, (end - begin) >> PAGE_SHIFT);
+ set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
+
+ printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
+
+ for (; addr < end; addr += PAGE_SIZE) {
+ ClearPageReserved(virt_to_page(addr));
+ init_page_count(virt_to_page(addr));
+ memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
+ free_page(addr);
+ totalram_pages++;
+ }
+#endif
+}
+
+void free_initmem(void)
+{
+ free_init_pages("unused kernel memory",
+ (unsigned long)(&__init_begin),
+ (unsigned long)(&__init_end));
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ /*
+ * end could be not aligned, and We can not align that,
+ * decompresser could be confused by aligned initrd_end
+ * We already reserve the end partial page before in
+ * - i386_start_kernel()
+ * - x86_64_start_kernel()
+ * - relocate_initrd()
+ * So here We can do PAGE_ALIGN() safely to get partial page to be freed
+ */
+ free_init_pages("initrd memory", start, PAGE_ALIGN(end));
+}
+#endif
+
+void __init zone_sizes_init(void)
+{
+ unsigned long max_zone_pfns[MAX_NR_ZONES];
+
+ memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+
+#ifdef CONFIG_ZONE_DMA
+ max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
+#endif
+#ifdef CONFIG_ZONE_DMA32
+ max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
+#endif
+ max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
+#ifdef CONFIG_HIGHMEM
+ max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
+#endif
+
+ free_area_init_nodes(max_zone_pfns);
+}
+