| /* |
| * Debug helper to dump the current kernel pagetables of the system |
| * so that we can see what the various memory ranges are set to. |
| * |
| * Derived from x86 implementation: |
| * (C) Copyright 2008 Intel Corporation |
| * |
| * Author: Arjan van de Ven <arjan@linux.intel.com> |
| * |
| * 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/mm.h> |
| #include <linux/seq_file.h> |
| |
| #include <asm/domain.h> |
| #include <asm/fixmap.h> |
| #include <asm/memory.h> |
| #include <asm/pgtable.h> |
| |
| struct addr_marker { |
| unsigned long start_address; |
| const char *name; |
| }; |
| |
| static struct addr_marker address_markers[] = { |
| { MODULES_VADDR, "Modules" }, |
| { PAGE_OFFSET, "Kernel Mapping" }, |
| { 0, "vmalloc() Area" }, |
| { VMALLOC_END, "vmalloc() End" }, |
| { FIXADDR_START, "Fixmap Area" }, |
| { VECTORS_BASE, "Vectors" }, |
| { VECTORS_BASE + PAGE_SIZE * 2, "Vectors End" }, |
| { -1, NULL }, |
| }; |
| |
| struct pg_state { |
| struct seq_file *seq; |
| const struct addr_marker *marker; |
| unsigned long start_address; |
| unsigned level; |
| u64 current_prot; |
| const char *current_domain; |
| }; |
| |
| struct prot_bits { |
| u64 mask; |
| u64 val; |
| const char *set; |
| const char *clear; |
| }; |
| |
| static const struct prot_bits pte_bits[] = { |
| { |
| .mask = L_PTE_USER, |
| .val = L_PTE_USER, |
| .set = "USR", |
| .clear = " ", |
| }, { |
| .mask = L_PTE_RDONLY, |
| .val = L_PTE_RDONLY, |
| .set = "ro", |
| .clear = "RW", |
| }, { |
| .mask = L_PTE_XN, |
| .val = L_PTE_XN, |
| .set = "NX", |
| .clear = "x ", |
| }, { |
| .mask = L_PTE_SHARED, |
| .val = L_PTE_SHARED, |
| .set = "SHD", |
| .clear = " ", |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_UNCACHED, |
| .set = "SO/UNCACHED", |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_BUFFERABLE, |
| .set = "MEM/BUFFERABLE/WC", |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_WRITETHROUGH, |
| .set = "MEM/CACHED/WT", |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_WRITEBACK, |
| .set = "MEM/CACHED/WBRA", |
| #ifndef CONFIG_ARM_LPAE |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_MINICACHE, |
| .set = "MEM/MINICACHE", |
| #endif |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_WRITEALLOC, |
| .set = "MEM/CACHED/WBWA", |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_DEV_SHARED, |
| .set = "DEV/SHARED", |
| #ifndef CONFIG_ARM_LPAE |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_DEV_NONSHARED, |
| .set = "DEV/NONSHARED", |
| #endif |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_DEV_WC, |
| .set = "DEV/WC", |
| }, { |
| .mask = L_PTE_MT_MASK, |
| .val = L_PTE_MT_DEV_CACHED, |
| .set = "DEV/CACHED", |
| }, |
| }; |
| |
| static const struct prot_bits section_bits[] = { |
| #ifdef CONFIG_ARM_LPAE |
| { |
| .mask = PMD_SECT_USER, |
| .val = PMD_SECT_USER, |
| .set = "USR", |
| }, { |
| .mask = L_PMD_SECT_RDONLY | PMD_SECT_AP2, |
| .val = L_PMD_SECT_RDONLY | PMD_SECT_AP2, |
| .set = "ro", |
| .clear = "RW", |
| #elif __LINUX_ARM_ARCH__ >= 6 |
| { |
| .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = PMD_SECT_APX | PMD_SECT_AP_WRITE, |
| .set = " ro", |
| }, { |
| .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = PMD_SECT_AP_WRITE, |
| .set = " RW", |
| }, { |
| .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = PMD_SECT_AP_READ, |
| .set = "USR ro", |
| }, { |
| .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .set = "USR RW", |
| #else /* ARMv4/ARMv5 */ |
| /* These are approximate */ |
| { |
| .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = 0, |
| .set = " ro", |
| }, { |
| .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = PMD_SECT_AP_WRITE, |
| .set = " RW", |
| }, { |
| .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = PMD_SECT_AP_READ, |
| .set = "USR ro", |
| }, { |
| .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .val = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE, |
| .set = "USR RW", |
| #endif |
| }, { |
| .mask = PMD_SECT_XN, |
| .val = PMD_SECT_XN, |
| .set = "NX", |
| .clear = "x ", |
| }, { |
| .mask = PMD_SECT_S, |
| .val = PMD_SECT_S, |
| .set = "SHD", |
| .clear = " ", |
| }, |
| }; |
| |
| struct pg_level { |
| const struct prot_bits *bits; |
| size_t num; |
| u64 mask; |
| }; |
| |
| static struct pg_level pg_level[] = { |
| { |
| }, { /* pgd */ |
| }, { /* pud */ |
| }, { /* pmd */ |
| .bits = section_bits, |
| .num = ARRAY_SIZE(section_bits), |
| }, { /* pte */ |
| .bits = pte_bits, |
| .num = ARRAY_SIZE(pte_bits), |
| }, |
| }; |
| |
| static void dump_prot(struct pg_state *st, const struct prot_bits *bits, size_t num) |
| { |
| unsigned i; |
| |
| for (i = 0; i < num; i++, bits++) { |
| const char *s; |
| |
| if ((st->current_prot & bits->mask) == bits->val) |
| s = bits->set; |
| else |
| s = bits->clear; |
| |
| if (s) |
| seq_printf(st->seq, " %s", s); |
| } |
| } |
| |
| static void note_page(struct pg_state *st, unsigned long addr, |
| unsigned int level, u64 val, const char *domain) |
| { |
| static const char units[] = "KMGTPE"; |
| u64 prot = val & pg_level[level].mask; |
| |
| if (!st->level) { |
| st->level = level; |
| st->current_prot = prot; |
| st->current_domain = domain; |
| seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); |
| } else if (prot != st->current_prot || level != st->level || |
| domain != st->current_domain || |
| addr >= st->marker[1].start_address) { |
| const char *unit = units; |
| unsigned long delta; |
| |
| if (st->current_prot) { |
| seq_printf(st->seq, "0x%08lx-0x%08lx ", |
| st->start_address, addr); |
| |
| delta = (addr - st->start_address) >> 10; |
| while (!(delta & 1023) && unit[1]) { |
| delta >>= 10; |
| unit++; |
| } |
| seq_printf(st->seq, "%9lu%c", delta, *unit); |
| if (st->current_domain) |
| seq_printf(st->seq, " %s", st->current_domain); |
| if (pg_level[st->level].bits) |
| dump_prot(st, pg_level[st->level].bits, pg_level[st->level].num); |
| seq_printf(st->seq, "\n"); |
| } |
| |
| if (addr >= st->marker[1].start_address) { |
| st->marker++; |
| seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); |
| } |
| st->start_address = addr; |
| st->current_prot = prot; |
| st->current_domain = domain; |
| st->level = level; |
| } |
| } |
| |
| static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start, |
| const char *domain) |
| { |
| pte_t *pte = pte_offset_kernel(pmd, 0); |
| unsigned long addr; |
| unsigned i; |
| |
| for (i = 0; i < PTRS_PER_PTE; i++, pte++) { |
| addr = start + i * PAGE_SIZE; |
| note_page(st, addr, 4, pte_val(*pte), domain); |
| } |
| } |
| |
| static const char *get_domain_name(pmd_t *pmd) |
| { |
| #ifndef CONFIG_ARM_LPAE |
| switch (pmd_val(*pmd) & PMD_DOMAIN_MASK) { |
| case PMD_DOMAIN(DOMAIN_KERNEL): |
| return "KERNEL "; |
| case PMD_DOMAIN(DOMAIN_USER): |
| return "USER "; |
| case PMD_DOMAIN(DOMAIN_IO): |
| return "IO "; |
| case PMD_DOMAIN(DOMAIN_VECTORS): |
| return "VECTORS"; |
| default: |
| return "unknown"; |
| } |
| #endif |
| return NULL; |
| } |
| |
| 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 i; |
| const char *domain; |
| |
| for (i = 0; i < PTRS_PER_PMD; i++, pmd++) { |
| addr = start + i * PMD_SIZE; |
| domain = get_domain_name(pmd); |
| if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd)) |
| note_page(st, addr, 3, pmd_val(*pmd), domain); |
| else |
| walk_pte(st, pmd, addr, domain); |
| |
| if (SECTION_SIZE < PMD_SIZE && pmd_large(pmd[1])) { |
| addr += SECTION_SIZE; |
| pmd++; |
| domain = get_domain_name(pmd); |
| note_page(st, addr, 3, pmd_val(*pmd), domain); |
| } |
| } |
| } |
| |
| 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 i; |
| |
| for (i = 0; i < PTRS_PER_PUD; i++, pud++) { |
| addr = start + i * PUD_SIZE; |
| if (!pud_none(*pud)) { |
| walk_pmd(st, pud, addr); |
| } else { |
| note_page(st, addr, 2, pud_val(*pud), NULL); |
| } |
| } |
| } |
| |
| static void walk_pgd(struct seq_file *m) |
| { |
| pgd_t *pgd = swapper_pg_dir; |
| struct pg_state st; |
| unsigned long addr; |
| unsigned i; |
| |
| memset(&st, 0, sizeof(st)); |
| st.seq = m; |
| st.marker = address_markers; |
| |
| for (i = 0; i < PTRS_PER_PGD; i++, pgd++) { |
| addr = i * PGDIR_SIZE; |
| if (!pgd_none(*pgd)) { |
| walk_pud(&st, pgd, addr); |
| } else { |
| note_page(&st, addr, 1, pgd_val(*pgd), NULL); |
| } |
| } |
| |
| note_page(&st, 0, 0, 0, NULL); |
| } |
| |
| static int ptdump_show(struct seq_file *m, void *v) |
| { |
| walk_pgd(m); |
| 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 int ptdump_init(void) |
| { |
| struct dentry *pe; |
| unsigned i, j; |
| |
| for (i = 0; i < ARRAY_SIZE(pg_level); i++) |
| if (pg_level[i].bits) |
| for (j = 0; j < pg_level[i].num; j++) |
| pg_level[i].mask |= pg_level[i].bits[j].mask; |
| |
| address_markers[2].start_address = VMALLOC_START; |
| |
| pe = debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, |
| &ptdump_fops); |
| return pe ? 0 : -ENOMEM; |
| } |
| __initcall(ptdump_init); |