diff options
Diffstat (limited to 'arch/powerpc/mm/dump_hashpagetable.c')
| -rw-r--r-- | arch/powerpc/mm/dump_hashpagetable.c | 550 |
1 files changed, 0 insertions, 550 deletions
diff --git a/arch/powerpc/mm/dump_hashpagetable.c b/arch/powerpc/mm/dump_hashpagetable.c deleted file mode 100644 index 869294695048..000000000000 --- a/arch/powerpc/mm/dump_hashpagetable.c +++ /dev/null @@ -1,550 +0,0 @@ -/* - * Copyright 2016, Rashmica Gupta, IBM Corp. - * - * This traverses the kernel virtual memory and dumps the pages that are in - * the hash pagetable, along with their flags to - * /sys/kernel/debug/kernel_hash_pagetable. - * - * If radix is enabled then there is no hash page table and so no debugfs file - * is generated. - * - * 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/io.h> -#include <linux/mm.h> -#include <linux/sched.h> -#include <linux/seq_file.h> -#include <asm/pgtable.h> -#include <linux/const.h> -#include <asm/page.h> -#include <asm/pgalloc.h> -#include <asm/plpar_wrappers.h> -#include <linux/memblock.h> -#include <asm/firmware.h> - -struct pg_state { - struct seq_file *seq; - const struct addr_marker *marker; - unsigned long start_address; - 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" }, - { 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" }, - { -1, NULL }, -}; - -struct flag_info { - u64 mask; - u64 val; - const char *set; - const char *clear; - bool is_val; - int shift; -}; - -static const struct flag_info v_flag_array[] = { - { - .mask = SLB_VSID_B, - .val = SLB_VSID_B_256M, - .set = "ssize: 256M", - .clear = "ssize: 1T ", - }, { - .mask = HPTE_V_SECONDARY, - .val = HPTE_V_SECONDARY, - .set = "secondary", - .clear = "primary ", - }, { - .mask = HPTE_V_VALID, - .val = HPTE_V_VALID, - .set = "valid ", - .clear = "invalid", - }, { - .mask = HPTE_V_BOLTED, - .val = HPTE_V_BOLTED, - .set = "bolted", - .clear = "", - } -}; - -static const struct flag_info r_flag_array[] = { - { - .mask = HPTE_R_PP0 | HPTE_R_PP, - .val = PP_RWXX, - .set = "prot:RW--", - }, { - .mask = HPTE_R_PP0 | HPTE_R_PP, - .val = PP_RWRX, - .set = "prot:RWR-", - }, { - .mask = HPTE_R_PP0 | HPTE_R_PP, - .val = PP_RWRW, - .set = "prot:RWRW", - }, { - .mask = HPTE_R_PP0 | HPTE_R_PP, - .val = PP_RXRX, - .set = "prot:R-R-", - }, { - .mask = HPTE_R_PP0 | HPTE_R_PP, - .val = PP_RXXX, - .set = "prot:R---", - }, { - .mask = HPTE_R_KEY_HI | HPTE_R_KEY_LO, - .val = HPTE_R_KEY_HI | HPTE_R_KEY_LO, - .set = "key", - .clear = "", - .is_val = true, - }, { - .mask = HPTE_R_R, - .val = HPTE_R_R, - .set = "ref", - .clear = " ", - }, { - .mask = HPTE_R_C, - .val = HPTE_R_C, - .set = "changed", - .clear = " ", - }, { - .mask = HPTE_R_N, - .val = HPTE_R_N, - .set = "no execute", - }, { - .mask = HPTE_R_WIMG, - .val = HPTE_R_W, - .set = "writethru", - }, { - .mask = HPTE_R_WIMG, - .val = HPTE_R_I, - .set = "no cache", - }, { - .mask = HPTE_R_WIMG, - .val = HPTE_R_G, - .set = "guarded", - } -}; - -static int calculate_pagesize(struct pg_state *st, int ps, char s[]) -{ - static const char units[] = "BKMGTPE"; - const char *unit = units; - - while (ps > 9 && unit[1]) { - ps -= 10; - unit++; - } - seq_printf(st->seq, " %s_ps: %i%c\t", s, 1<<ps, *unit); - return ps; -} - -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); - } - } -} - -static void dump_hpte_info(struct pg_state *st, unsigned long ea, u64 v, u64 r, - unsigned long rpn, int bps, int aps, unsigned long lp) -{ - int aps_index; - - while (ea >= st->marker[1].start_address) { - st->marker++; - seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); - } - seq_printf(st->seq, "0x%lx:\t", ea); - seq_printf(st->seq, "AVPN:%llx\t", HPTE_V_AVPN_VAL(v)); - dump_flag_info(st, v_flag_array, v, ARRAY_SIZE(v_flag_array)); - seq_printf(st->seq, " rpn: %lx\t", rpn); - dump_flag_info(st, r_flag_array, r, ARRAY_SIZE(r_flag_array)); - - calculate_pagesize(st, bps, "base"); - aps_index = calculate_pagesize(st, aps, "actual"); - if (aps_index != 2) - seq_printf(st->seq, "LP enc: %lx", lp); - seq_putc(st->seq, '\n'); -} - - -static int native_find(unsigned long ea, int psize, bool primary, u64 *v, u64 - *r) -{ - struct hash_pte *hptep; - unsigned long hash, vsid, vpn, hpte_group, want_v, hpte_v; - int i, ssize = mmu_kernel_ssize; - unsigned long shift = mmu_psize_defs[psize].shift; - - /* calculate hash */ - vsid = get_kernel_vsid(ea, ssize); - vpn = hpt_vpn(ea, vsid, ssize); - hash = hpt_hash(vpn, shift, ssize); - want_v = hpte_encode_avpn(vpn, psize, ssize); - - /* to check in the secondary hash table, we invert the hash */ - if (!primary) - hash = ~hash; - hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; - for (i = 0; i < HPTES_PER_GROUP; i++) { - hptep = htab_address + hpte_group; - hpte_v = be64_to_cpu(hptep->v); - - if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID)) { - /* HPTE matches */ - *v = be64_to_cpu(hptep->v); - *r = be64_to_cpu(hptep->r); - return 0; - } - ++hpte_group; - } - return -1; -} - -#ifdef CONFIG_PPC_PSERIES -static int pseries_find(unsigned long ea, int psize, bool primary, u64 *v, u64 *r) -{ - struct hash_pte ptes[4]; - unsigned long vsid, vpn, hash, hpte_group, want_v; - int i, j, ssize = mmu_kernel_ssize; - long lpar_rc = 0; - unsigned long shift = mmu_psize_defs[psize].shift; - - /* calculate hash */ - vsid = get_kernel_vsid(ea, ssize); - vpn = hpt_vpn(ea, vsid, ssize); - hash = hpt_hash(vpn, shift, ssize); - want_v = hpte_encode_avpn(vpn, psize, ssize); - - /* to check in the secondary hash table, we invert the hash */ - if (!primary) - hash = ~hash; - hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; - /* see if we can find an entry in the hpte with this hash */ - for (i = 0; i < HPTES_PER_GROUP; i += 4, hpte_group += 4) { - lpar_rc = plpar_pte_read_4(0, hpte_group, (void *)ptes); - - if (lpar_rc != H_SUCCESS) - continue; - for (j = 0; j < 4; j++) { - if (HPTE_V_COMPARE(ptes[j].v, want_v) && - (ptes[j].v & HPTE_V_VALID)) { - /* HPTE matches */ - *v = ptes[j].v; - *r = ptes[j].r; - return 0; - } - } - } - return -1; -} -#endif - -static void decode_r(int bps, unsigned long r, unsigned long *rpn, int *aps, - unsigned long *lp_bits) -{ - struct mmu_psize_def entry; - unsigned long arpn, mask, lp; - int penc = -2, idx = 0, shift; - - /*. - * The LP field has 8 bits. Depending on the actual page size, some of - * these bits are concatenated with the APRN to get the RPN. The rest - * of the bits in the LP field is the LP value and is an encoding for - * the base page size and the actual page size. - * - * - find the mmu entry for our base page size - * - go through all page encodings and use the associated mask to - * find an encoding that matches our encoding in the LP field. - */ - arpn = (r & HPTE_R_RPN) >> HPTE_R_RPN_SHIFT; - lp = arpn & 0xff; - - entry = mmu_psize_defs[bps]; - while (idx < MMU_PAGE_COUNT) { - penc = entry.penc[idx]; - if ((penc != -1) && (mmu_psize_defs[idx].shift)) { - shift = mmu_psize_defs[idx].shift - HPTE_R_RPN_SHIFT; - mask = (0x1 << (shift)) - 1; - if ((lp & mask) == penc) { - *aps = mmu_psize_to_shift(idx); - *lp_bits = lp & mask; - *rpn = arpn >> shift; - return; - } - } - idx++; - } -} - -static int base_hpte_find(unsigned long ea, int psize, bool primary, u64 *v, - u64 *r) -{ -#ifdef CONFIG_PPC_PSERIES - if (firmware_has_feature(FW_FEATURE_LPAR)) - return pseries_find(ea, psize, primary, v, r); -#endif - return native_find(ea, psize, primary, v, r); -} - -static unsigned long hpte_find(struct pg_state *st, unsigned long ea, int psize) -{ - unsigned long slot; - u64 v = 0, r = 0; - unsigned long rpn, lp_bits; - int base_psize = 0, actual_psize = 0; - - if (ea < PAGE_OFFSET) - return -1; - - /* Look in primary table */ - slot = base_hpte_find(ea, psize, true, &v, &r); - - /* Look in secondary table */ - if (slot == -1) - slot = base_hpte_find(ea, psize, true, &v, &r); - - /* No entry found */ - if (slot == -1) - return -1; - - /* - * We found an entry in the hash page table: - * - check that this has the same base page - * - find the actual page size - * - find the RPN - */ - base_psize = mmu_psize_to_shift(psize); - - if ((v & HPTE_V_LARGE) == HPTE_V_LARGE) { - decode_r(psize, r, &rpn, &actual_psize, &lp_bits); - } else { - /* 4K actual page size */ - actual_psize = 12; - rpn = (r & HPTE_R_RPN) >> HPTE_R_RPN_SHIFT; - /* In this case there are no LP bits */ - lp_bits = -1; - } - /* - * We didn't find a matching encoding, so the PTE we found isn't for - * this address. - */ - if (actual_psize == -1) - return -1; - - dump_hpte_info(st, ea, v, r, rpn, base_psize, actual_psize, lp_bits); - return 0; -} - -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, pteval, psize; - int i, status; - - for (i = 0; i < PTRS_PER_PTE; i++, pte++) { - addr = start + i * PAGE_SIZE; - pteval = pte_val(*pte); - - if (addr < VMALLOC_END) - psize = mmu_vmalloc_psize; - else - psize = mmu_io_psize; -#ifdef CONFIG_PPC_64K_PAGES - /* check for secret 4K mappings */ - if (((pteval & H_PAGE_COMBO) == H_PAGE_COMBO) || - ((pteval & H_PAGE_4K_PFN) == H_PAGE_4K_PFN)) - psize = mmu_io_psize; -#endif - /* check for hashpte */ - status = hpte_find(st, addr, psize); - - if (((pteval & H_PAGE_HASHPTE) != H_PAGE_HASHPTE) - && (status != -1)) { - /* found a hpte that is not in the linux page tables */ - seq_printf(st->seq, "page probably bolted before linux" - " pagetables were set: addr:%lx, pteval:%lx\n", - addr, pteval); - } - } -} - -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 exists */ - walk_pte(st, pmd, addr); - } -} - -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 exists */ - walk_pmd(st, pud, addr); - } -} - -static void walk_pagetables(struct pg_state *st) -{ - pgd_t *pgd = pgd_offset_k(0UL); - unsigned int i; - unsigned long addr; - - /* - * Traverse the linux pagetable structure and dump pages that are in - * the hash pagetable. - */ - for (i = 0; i < PTRS_PER_PGD; i++, pgd++) { - addr = KERN_VIRT_START + i * PGDIR_SIZE; - if (!pgd_none(*pgd)) - /* pgd exists */ - walk_pud(st, pgd, addr); - } -} - - -static void walk_linearmapping(struct pg_state *st) -{ - unsigned long addr; - - /* - * Traverse the linear mapping section of virtual memory and dump pages - * that are in the hash pagetable. - */ - unsigned long psize = 1 << mmu_psize_defs[mmu_linear_psize].shift; - - for (addr = PAGE_OFFSET; addr < PAGE_OFFSET + - memblock_end_of_DRAM(); addr += psize) - hpte_find(st, addr, mmu_linear_psize); -} - -static void walk_vmemmap(struct pg_state *st) -{ -#ifdef CONFIG_SPARSEMEM_VMEMMAP - struct vmemmap_backing *ptr = vmemmap_list; - - /* - * Traverse the vmemmaped memory and dump pages that are in the hash - * pagetable. - */ - while (ptr->list) { - hpte_find(st, ptr->virt_addr, mmu_vmemmap_psize); - ptr = ptr->list; - } - seq_puts(st->seq, "---[ vmemmap end ]---\n"); -#endif -} - -static void populate_markers(void) -{ - address_markers[0].start_address = PAGE_OFFSET; - address_markers[1].start_address = VMALLOC_START; - address_markers[2].start_address = VMALLOC_END; - address_markers[3].start_address = ISA_IO_BASE; - address_markers[4].start_address = ISA_IO_END; - address_markers[5].start_address = PHB_IO_BASE; - address_markers[6].start_address = PHB_IO_END; - address_markers[7].start_address = IOREMAP_BASE; - address_markers[8].start_address = IOREMAP_END; -#ifdef CONFIG_PPC_BOOK3S_64 - address_markers[9].start_address = H_VMEMMAP_BASE; -#else - address_markers[9].start_address = VMEMMAP_BASE; -#endif -} - -static int ptdump_show(struct seq_file *m, void *v) -{ - struct pg_state st = { - .seq = m, - .start_address = PAGE_OFFSET, - .marker = address_markers, - }; - /* - * Traverse the 0xc, 0xd and 0xf areas of the kernel virtual memory and - * dump pages that are in the hash pagetable. - */ - walk_linearmapping(&st); - walk_pagetables(&st); - walk_vmemmap(&st); - 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 *debugfs_file; - - if (!radix_enabled()) { - populate_markers(); - debugfs_file = debugfs_create_file("kernel_hash_pagetable", - 0400, NULL, NULL, &ptdump_fops); - return debugfs_file ? 0 : -ENOMEM; - } - return 0; -} -device_initcall(ptdump_init); |