mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
550 lines
13 KiB
550 lines
13 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* 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. |
|
*/ |
|
#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 <linux/const.h> |
|
#include <asm/page.h> |
|
#include <asm/plpar_wrappers.h> |
|
#include <linux/memblock.h> |
|
#include <asm/firmware.h> |
|
#include <asm/pgalloc.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; |
|
} |
|
|
|
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) |
|
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; |
|
} |
|
|
|
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) |
|
{ |
|
if (IS_ENABLED(CONFIG_PPC_PSERIES) && firmware_has_feature(FW_FEATURE_LPAR)) |
|
return pseries_find(ea, psize, primary, v, r); |
|
|
|
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, false, &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; |
|
|
|
/* check for secret 4K mappings */ |
|
if (IS_ENABLED(CONFIG_PPC_64K_PAGES) && |
|
((pteval & H_PAGE_COMBO) == H_PAGE_COMBO || |
|
(pteval & H_PAGE_4K_PFN) == H_PAGE_4K_PFN)) |
|
psize = mmu_io_psize; |
|
|
|
/* 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, p4d_t *p4d, unsigned long start) |
|
{ |
|
pud_t *pud = pud_offset(p4d, 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_p4d(struct pg_state *st, pgd_t *pgd, unsigned long start) |
|
{ |
|
p4d_t *p4d = p4d_offset(pgd, 0); |
|
unsigned long addr; |
|
unsigned int i; |
|
|
|
for (i = 0; i < PTRS_PER_P4D; i++, p4d++) { |
|
addr = start + i * P4D_SIZE; |
|
if (!p4d_none(*p4d)) |
|
/* p4d exists */ |
|
walk_pud(st, p4d, 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_p4d(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) |
|
{ |
|
struct vmemmap_backing *ptr = vmemmap_list; |
|
|
|
if (!IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP)) |
|
return; |
|
/* |
|
* 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"); |
|
} |
|
|
|
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; |
|
address_markers[9].start_address = H_VMEMMAP_START; |
|
} |
|
|
|
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) |
|
{ |
|
if (!radix_enabled()) { |
|
populate_markers(); |
|
debugfs_create_file("kernel_hash_pagetable", 0400, NULL, NULL, |
|
&ptdump_fops); |
|
} |
|
return 0; |
|
} |
|
device_initcall(ptdump_init);
|
|
|