diff options
Diffstat (limited to 'arch/powerpc/mm/dump_linuxpagetables.c')
| -rw-r--r-- | arch/powerpc/mm/dump_linuxpagetables.c | 373 |
1 files changed, 0 insertions, 373 deletions
diff --git a/arch/powerpc/mm/dump_linuxpagetables.c b/arch/powerpc/mm/dump_linuxpagetables.c deleted file mode 100644 index 6aa41669ac1a..000000000000 --- a/arch/powerpc/mm/dump_linuxpagetables.c +++ /dev/null @@ -1,373 +0,0 @@ -/* - * Copyright 2016, Rashmica Gupta, IBM Corp. - * - * This traverses the kernel pagetables and dumps the - * information about the used sections of memory to - * /sys/kernel/debug/kernel_pagetables. - * - * Derived from the arm64 implementation: - * Copyright (c) 2014, The Linux Foundation, Laura Abbott. - * (C) Copyright 2008 Intel Corporation, Arjan van de Ven. - * - * 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 - * of the License. - */ -#include <linux/debugfs.h> -#include <linux/fs.h> -#include <linux/hugetlb.h> -#include <linux/io.h> -#include <linux/mm.h> -#include <linux/highmem.h> -#include <linux/sched.h> -#include <linux/seq_file.h> -#include <asm/fixmap.h> -#include <asm/pgtable.h> -#include <linux/const.h> -#include <asm/page.h> -#include <asm/pgalloc.h> - -#include "dump_linuxpagetables.h" - -#ifdef CONFIG_PPC32 -#define KERN_VIRT_START 0 -#endif - -/* - * To visualise what is happening, - * - * - PTRS_PER_P** = how many entries there are in the corresponding P** - * - P**_SHIFT = how many bits of the address we use to index into the - * corresponding P** - * - P**_SIZE is how much memory we can access through the table - not the - * size of the table itself. - * P**={PGD, PUD, PMD, PTE} - * - * - * Each entry of the PGD points to a PUD. Each entry of a PUD points to a - * PMD. Each entry of a PMD points to a PTE. And every PTE entry points to - * a page. - * - * In the case where there are only 3 levels, the PUD is folded into the - * PGD: every PUD has only one entry which points to the PMD. - * - * The page dumper groups page table entries of the same type into a single - * description. It uses pg_state to track the range information while - * iterating over the PTE entries. When the continuity is broken it then - * dumps out a description of the range - ie PTEs that are virtually contiguous - * with the same PTE flags are chunked together. This is to make it clear how - * different areas of the kernel virtual memory are used. - * - */ -struct pg_state { - struct seq_file *seq; - const struct addr_marker *marker; - unsigned long start_address; - unsigned long start_pa; - unsigned long last_pa; - unsigned int level; - u64 current_flags; -}; - -struct addr_marker { - unsigned long start_address; - const char *name; -}; - -static struct addr_marker address_markers[] = { - { 0, "Start of kernel VM" }, - { 0, "vmalloc() Area" }, - { 0, "vmalloc() End" }, -#ifdef CONFIG_PPC64 - { 0, "isa I/O start" }, - { 0, "isa I/O end" }, - { 0, "phb I/O start" }, - { 0, "phb I/O end" }, - { 0, "I/O remap start" }, - { 0, "I/O remap end" }, - { 0, "vmemmap start" }, -#else - { 0, "Early I/O remap start" }, - { 0, "Early I/O remap end" }, -#ifdef CONFIG_NOT_COHERENT_CACHE - { 0, "Consistent mem start" }, - { 0, "Consistent mem end" }, -#endif -#ifdef CONFIG_HIGHMEM - { 0, "Highmem PTEs start" }, - { 0, "Highmem PTEs end" }, -#endif - { 0, "Fixmap start" }, - { 0, "Fixmap end" }, -#endif - { -1, NULL }, -}; - -static void dump_flag_info(struct pg_state *st, const struct flag_info - *flag, u64 pte, int num) -{ - unsigned int i; - - for (i = 0; i < num; i++, flag++) { - const char *s = NULL; - u64 val; - - /* flag not defined so don't check it */ - if (flag->mask == 0) - continue; - /* Some 'flags' are actually values */ - if (flag->is_val) { - val = pte & flag->val; - if (flag->shift) - val = val >> flag->shift; - seq_printf(st->seq, " %s:%llx", flag->set, val); - } else { - if ((pte & flag->mask) == flag->val) - s = flag->set; - else - s = flag->clear; - if (s) - seq_printf(st->seq, " %s", s); - } - st->current_flags &= ~flag->mask; - } - if (st->current_flags != 0) - seq_printf(st->seq, " unknown flags:%llx", st->current_flags); -} - -static void dump_addr(struct pg_state *st, unsigned long addr) -{ - static const char units[] = "KMGTPE"; - const char *unit = units; - unsigned long delta; - -#ifdef CONFIG_PPC64 - seq_printf(st->seq, "0x%016lx-0x%016lx ", st->start_address, addr-1); - seq_printf(st->seq, "0x%016lx ", st->start_pa); -#else - seq_printf(st->seq, "0x%08lx-0x%08lx ", st->start_address, addr - 1); - seq_printf(st->seq, "0x%08lx ", st->start_pa); -#endif - - delta = (addr - st->start_address) >> 10; - /* Work out what appropriate unit to use */ - while (!(delta & 1023) && unit[1]) { - delta >>= 10; - unit++; - } - seq_printf(st->seq, "%9lu%c", delta, *unit); - -} - -static void note_page(struct pg_state *st, unsigned long addr, - unsigned int level, u64 val) -{ - u64 flag = val & pg_level[level].mask; - u64 pa = val & PTE_RPN_MASK; - - /* At first no level is set */ - if (!st->level) { - st->level = level; - st->current_flags = flag; - st->start_address = addr; - st->start_pa = pa; - st->last_pa = pa; - seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); - /* - * Dump the section of virtual memory when: - * - the PTE flags from one entry to the next differs. - * - we change levels in the tree. - * - the address is in a different section of memory and is thus - * used for a different purpose, regardless of the flags. - * - the pa of this page is not adjacent to the last inspected page - */ - } else if (flag != st->current_flags || level != st->level || - addr >= st->marker[1].start_address || - pa != st->last_pa + PAGE_SIZE) { - - /* Check the PTE flags */ - if (st->current_flags) { - dump_addr(st, addr); - - /* Dump all the flags */ - if (pg_level[st->level].flag) - dump_flag_info(st, pg_level[st->level].flag, - st->current_flags, - pg_level[st->level].num); - - seq_putc(st->seq, '\n'); - } - - /* - * Address indicates we have passed the end of the - * current section of virtual memory - */ - while (addr >= st->marker[1].start_address) { - st->marker++; - seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); - } - st->start_address = addr; - st->start_pa = pa; - st->last_pa = pa; - st->current_flags = flag; - st->level = level; - } else { - st->last_pa = pa; - } -} - -static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start) -{ - pte_t *pte = pte_offset_kernel(pmd, 0); - unsigned long addr; - unsigned int i; - - for (i = 0; i < PTRS_PER_PTE; i++, pte++) { - addr = start + i * PAGE_SIZE; - note_page(st, addr, 4, pte_val(*pte)); - - } -} - -static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start) -{ - pmd_t *pmd = pmd_offset(pud, 0); - unsigned long addr; - unsigned int i; - - for (i = 0; i < PTRS_PER_PMD; i++, pmd++) { - addr = start + i * PMD_SIZE; - if (!pmd_none(*pmd) && !pmd_huge(*pmd)) - /* pmd exists */ - walk_pte(st, pmd, addr); - else - note_page(st, addr, 3, pmd_val(*pmd)); - } -} - -static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start) -{ - pud_t *pud = pud_offset(pgd, 0); - unsigned long addr; - unsigned int i; - - for (i = 0; i < PTRS_PER_PUD; i++, pud++) { - addr = start + i * PUD_SIZE; - if (!pud_none(*pud) && !pud_huge(*pud)) - /* pud exists */ - walk_pmd(st, pud, addr); - else - note_page(st, addr, 2, pud_val(*pud)); - } -} - -static void walk_pagetables(struct pg_state *st) -{ - pgd_t *pgd = pgd_offset_k(0UL); - unsigned int i; - unsigned long addr; - - addr = st->start_address; - - /* - * Traverse the linux pagetable structure and dump pages that are in - * the hash pagetable. - */ - for (i = 0; i < PTRS_PER_PGD; i++, pgd++, addr += PGDIR_SIZE) { - if (!pgd_none(*pgd) && !pgd_huge(*pgd)) - /* pgd exists */ - walk_pud(st, pgd, addr); - else - note_page(st, addr, 1, pgd_val(*pgd)); - } -} - -static void populate_markers(void) -{ - int i = 0; - - address_markers[i++].start_address = PAGE_OFFSET; - address_markers[i++].start_address = VMALLOC_START; - address_markers[i++].start_address = VMALLOC_END; -#ifdef CONFIG_PPC64 - address_markers[i++].start_address = ISA_IO_BASE; - address_markers[i++].start_address = ISA_IO_END; - address_markers[i++].start_address = PHB_IO_BASE; - address_markers[i++].start_address = PHB_IO_END; - address_markers[i++].start_address = IOREMAP_BASE; - address_markers[i++].start_address = IOREMAP_END; -#ifdef CONFIG_PPC_BOOK3S_64 - address_markers[i++].start_address = H_VMEMMAP_BASE; -#else - address_markers[i++].start_address = VMEMMAP_BASE; -#endif -#else /* !CONFIG_PPC64 */ - address_markers[i++].start_address = ioremap_bot; - address_markers[i++].start_address = IOREMAP_TOP; -#ifdef CONFIG_NOT_COHERENT_CACHE - address_markers[i++].start_address = IOREMAP_TOP; - address_markers[i++].start_address = IOREMAP_TOP + - CONFIG_CONSISTENT_SIZE; -#endif -#ifdef CONFIG_HIGHMEM - address_markers[i++].start_address = PKMAP_BASE; - address_markers[i++].start_address = PKMAP_ADDR(LAST_PKMAP); -#endif - address_markers[i++].start_address = FIXADDR_START; - address_markers[i++].start_address = FIXADDR_TOP; -#endif /* CONFIG_PPC64 */ -} - -static int ptdump_show(struct seq_file *m, void *v) -{ - struct pg_state st = { - .seq = m, - .marker = address_markers, - }; - - if (radix_enabled()) - st.start_address = PAGE_OFFSET; - else - st.start_address = KERN_VIRT_START; - - /* Traverse kernel page tables */ - walk_pagetables(&st); - note_page(&st, 0, 0, 0); - return 0; -} - - -static int ptdump_open(struct inode *inode, struct file *file) -{ - return single_open(file, ptdump_show, NULL); -} - -static const struct file_operations ptdump_fops = { - .open = ptdump_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static void build_pgtable_complete_mask(void) -{ - unsigned int i, j; - - for (i = 0; i < ARRAY_SIZE(pg_level); i++) - if (pg_level[i].flag) - for (j = 0; j < pg_level[i].num; j++) - pg_level[i].mask |= pg_level[i].flag[j].mask; -} - -static int ptdump_init(void) -{ - struct dentry *debugfs_file; - - populate_markers(); - build_pgtable_complete_mask(); - debugfs_file = debugfs_create_file("kernel_page_tables", 0400, NULL, - NULL, &ptdump_fops); - return debugfs_file ? 0 : -ENOMEM; -} -device_initcall(ptdump_init); |