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alistair23-linux/arch/powerpc/mm/hash_utils_64.c
Nicholas Piggin c610d65c0a powerpc/pseries: lift RTAS limit for hash 
With the previous patch to switch to 64-bit mode after returning from
RTAS and before doing any memory accesses, the RMA limit need not be
clamped to 1GB to avoid RTAS bugs.

Keep the 1GB limit for older firmware (although this is more of a kernel
concern than RTAS), and remove it starting with POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:45:34 +11:00

1900 lines
50 KiB
C
Raw Blame History

/*
* PowerPC64 port by Mike Corrigan and Dave Engebretsen
* {mikejc|engebret}@us.ibm.com
*
* Copyright (c) 2000 Mike Corrigan <mikejc@us.ibm.com>
*
* SMP scalability work:
* Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
*
* Module name: htab.c
*
* Description:
* PowerPC Hashed Page Table functions
*
* 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; either version
* 2 of the License, or (at your option) any later version.
*/
#undef DEBUG
#undef DEBUG_LOW
#define pr_fmt(fmt) "hash-mmu: " fmt
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/sched/mm.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/sysctl.h>
#include <linux/export.h>
#include <linux/ctype.h>
#include <linux/cache.h>
#include <linux/init.h>
#include <linux/signal.h>
#include <linux/memblock.h>
#include <linux/context_tracking.h>
#include <linux/libfdt.h>
#include <asm/debugfs.h>
#include <asm/processor.h>
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/mmu_context.h>
#include <asm/page.h>
#include <asm/types.h>
#include <linux/uaccess.h>
#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/tlbflush.h>
#include <asm/io.h>
#include <asm/eeh.h>
#include <asm/tlb.h>
#include <asm/cacheflush.h>
#include <asm/cputable.h>
#include <asm/sections.h>
#include <asm/copro.h>
#include <asm/udbg.h>
#include <asm/code-patching.h>
#include <asm/fadump.h>
#include <asm/firmware.h>
#include <asm/tm.h>
#include <asm/trace.h>
#include <asm/ps3.h>
#include <asm/pte-walk.h>
#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif
#ifdef DEBUG_LOW
#define DBG_LOW(fmt...) udbg_printf(fmt)
#else
#define DBG_LOW(fmt...)
#endif
#define KB (1024)
#define MB (1024*KB)
#define GB (1024L*MB)
/*
* Note: pte --> Linux PTE
* HPTE --> PowerPC Hashed Page Table Entry
*
* Execution context:
* htab_initialize is called with the MMU off (of course), but
* the kernel has been copied down to zero so it can directly
* reference global data. At this point it is very difficult
* to print debug info.
*
*/
static unsigned long _SDR1;
struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
EXPORT_SYMBOL_GPL(mmu_psize_defs);
u8 hpte_page_sizes[1 << LP_BITS];
EXPORT_SYMBOL_GPL(hpte_page_sizes);
struct hash_pte *htab_address;
unsigned long htab_size_bytes;
unsigned long htab_hash_mask;
EXPORT_SYMBOL_GPL(htab_hash_mask);
int mmu_linear_psize = MMU_PAGE_4K;
EXPORT_SYMBOL_GPL(mmu_linear_psize);
int mmu_virtual_psize = MMU_PAGE_4K;
int mmu_vmalloc_psize = MMU_PAGE_4K;
#ifdef CONFIG_SPARSEMEM_VMEMMAP
int mmu_vmemmap_psize = MMU_PAGE_4K;
#endif
int mmu_io_psize = MMU_PAGE_4K;
int mmu_kernel_ssize = MMU_SEGSIZE_256M;
EXPORT_SYMBOL_GPL(mmu_kernel_ssize);
int mmu_highuser_ssize = MMU_SEGSIZE_256M;
u16 mmu_slb_size = 64;
EXPORT_SYMBOL_GPL(mmu_slb_size);
#ifdef CONFIG_PPC_64K_PAGES
int mmu_ci_restrictions;
#endif
#ifdef CONFIG_DEBUG_PAGEALLOC
static u8 *linear_map_hash_slots;
static unsigned long linear_map_hash_count;
static DEFINE_SPINLOCK(linear_map_hash_lock);
#endif /* CONFIG_DEBUG_PAGEALLOC */
struct mmu_hash_ops mmu_hash_ops;
EXPORT_SYMBOL(mmu_hash_ops);
/* There are definitions of page sizes arrays to be used when none
* is provided by the firmware.
*/
/* Pre-POWER4 CPUs (4k pages only)
*/
static struct mmu_psize_def mmu_psize_defaults_old[] = {
[MMU_PAGE_4K] = {
.shift = 12,
.sllp = 0,
.penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1},
.avpnm = 0,
.tlbiel = 0,
},
};
/* POWER4, GPUL, POWER5
*
* Support for 16Mb large pages
*/
static struct mmu_psize_def mmu_psize_defaults_gp[] = {
[MMU_PAGE_4K] = {
.shift = 12,
.sllp = 0,
.penc = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1},
.avpnm = 0,
.tlbiel = 1,
},
[MMU_PAGE_16M] = {
.shift = 24,
.sllp = SLB_VSID_L,
.penc = {[0 ... MMU_PAGE_16M - 1] = -1, [MMU_PAGE_16M] = 0,
[MMU_PAGE_16M + 1 ... MMU_PAGE_COUNT - 1] = -1 },
.avpnm = 0x1UL,
.tlbiel = 0,
},
};
/*
* 'R' and 'C' update notes:
* - Under pHyp or KVM, the updatepp path will not set C, thus it *will*
* create writeable HPTEs without C set, because the hcall H_PROTECT
* that we use in that case will not update C
* - The above is however not a problem, because we also don't do that
* fancy "no flush" variant of eviction and we use H_REMOVE which will
* do the right thing and thus we don't have the race I described earlier
*
* - Under bare metal, we do have the race, so we need R and C set
* - We make sure R is always set and never lost
* - C is _PAGE_DIRTY, and *should* always be set for a writeable mapping
*/
unsigned long htab_convert_pte_flags(unsigned long pteflags)
{
unsigned long rflags = 0;
/* _PAGE_EXEC -> NOEXEC */
if ((pteflags & _PAGE_EXEC) == 0)
rflags |= HPTE_R_N;
/*
* PPP bits:
* Linux uses slb key 0 for kernel and 1 for user.
* kernel RW areas are mapped with PPP=0b000
* User area is mapped with PPP=0b010 for read/write
* or PPP=0b011 for read-only (including writeable but clean pages).
*/
if (pteflags & _PAGE_PRIVILEGED) {
/*
* Kernel read only mapped with ppp bits 0b110
*/
if (!(pteflags & _PAGE_WRITE)) {
if (mmu_has_feature(MMU_FTR_KERNEL_RO))
rflags |= (HPTE_R_PP0 | 0x2);
else
rflags |= 0x3;
}
} else {
if (pteflags & _PAGE_RWX)
rflags |= 0x2;
if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY)))
rflags |= 0x1;
}
/*
* We can't allow hardware to update hpte bits. Hence always
* set 'R' bit and set 'C' if it is a write fault
*/
rflags |= HPTE_R_R;
if (pteflags & _PAGE_DIRTY)
rflags |= HPTE_R_C;
/*
* Add in WIG bits
*/
if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_TOLERANT)
rflags |= HPTE_R_I;
else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT)
rflags |= (HPTE_R_I | HPTE_R_G);
else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_SAO)
rflags |= (HPTE_R_W | HPTE_R_I | HPTE_R_M);
else
/*
* Add memory coherence if cache inhibited is not set
*/
rflags |= HPTE_R_M;
return rflags;
}
int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
unsigned long pstart, unsigned long prot,
int psize, int ssize)
{
unsigned long vaddr, paddr;
unsigned int step, shift;
int ret = 0;
shift = mmu_psize_defs[psize].shift;
step = 1 << shift;
prot = htab_convert_pte_flags(prot);
DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n",
vstart, vend, pstart, prot, psize, ssize);
for (vaddr = vstart, paddr = pstart; vaddr < vend;
vaddr += step, paddr += step) {
unsigned long hash, hpteg;
unsigned long vsid = get_kernel_vsid(vaddr, ssize);
unsigned long vpn = hpt_vpn(vaddr, vsid, ssize);
unsigned long tprot = prot;
/*
* If we hit a bad address return error.
*/
if (!vsid)
return -1;
/* Make kernel text executable */
if (overlaps_kernel_text(vaddr, vaddr + step))
tprot &= ~HPTE_R_N;
/* Make kvm guest trampolines executable */
if (overlaps_kvm_tmp(vaddr, vaddr + step))
tprot &= ~HPTE_R_N;
/*
* If relocatable, check if it overlaps interrupt vectors that
* are copied down to real 0. For relocatable kernel
* (e.g. kdump case) we copy interrupt vectors down to real
* address 0. Mark that region as executable. This is
* because on p8 system with relocation on exception feature
* enabled, exceptions are raised with MMU (IR=DR=1) ON. Hence
* in order to execute the interrupt handlers in virtual
* mode the vector region need to be marked as executable.
*/
if ((PHYSICAL_START > MEMORY_START) &&
overlaps_interrupt_vector_text(vaddr, vaddr + step))
tprot &= ~HPTE_R_N;
hash = hpt_hash(vpn, shift, ssize);
hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
BUG_ON(!mmu_hash_ops.hpte_insert);
ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot,
HPTE_V_BOLTED, psize, psize,
ssize);
if (ret < 0)
break;
#ifdef CONFIG_DEBUG_PAGEALLOC
if (debug_pagealloc_enabled() &&
(paddr >> PAGE_SHIFT) < linear_map_hash_count)
linear_map_hash_slots[paddr >> PAGE_SHIFT] = ret | 0x80;
#endif /* CONFIG_DEBUG_PAGEALLOC */
}
return ret < 0 ? ret : 0;
}
int htab_remove_mapping(unsigned long vstart, unsigned long vend,
int psize, int ssize)
{
unsigned long vaddr;
unsigned int step, shift;
int rc;
int ret = 0;
shift = mmu_psize_defs[psize].shift;
step = 1 << shift;
if (!mmu_hash_ops.hpte_removebolted)
return -ENODEV;
for (vaddr = vstart; vaddr < vend; vaddr += step) {
rc = mmu_hash_ops.hpte_removebolted(vaddr, psize, ssize);
if (rc == -ENOENT) {
ret = -ENOENT;
continue;
}
if (rc < 0)
return rc;
}
return ret;
}
static bool disable_1tb_segments = false;
static int __init parse_disable_1tb_segments(char *p)
{
disable_1tb_segments = true;
return 0;
}
early_param("disable_1tb_segments", parse_disable_1tb_segments);
static int __init htab_dt_scan_seg_sizes(unsigned long node,
const char *uname, int depth,
void *data)
{
const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const __be32 *prop;
int size = 0;
/* We are scanning "cpu" nodes only */
if (type == NULL || strcmp(type, "cpu") != 0)
return 0;
prop = of_get_flat_dt_prop(node, "ibm,processor-segment-sizes", &size);
if (prop == NULL)
return 0;
for (; size >= 4; size -= 4, ++prop) {
if (be32_to_cpu(prop[0]) == 40) {
DBG("1T segment support detected\n");
if (disable_1tb_segments) {
DBG("1T segments disabled by command line\n");
break;
}
cur_cpu_spec->mmu_features |= MMU_FTR_1T_SEGMENT;
return 1;
}
}
cur_cpu_spec->mmu_features &= ~MMU_FTR_NO_SLBIE_B;
return 0;
}
static int __init get_idx_from_shift(unsigned int shift)
{
int idx = -1;
switch (shift) {
case 0xc:
idx = MMU_PAGE_4K;
break;
case 0x10:
idx = MMU_PAGE_64K;
break;
case 0x14:
idx = MMU_PAGE_1M;
break;
case 0x18:
idx = MMU_PAGE_16M;
break;
case 0x22:
idx = MMU_PAGE_16G;
break;
}
return idx;
}
static int __init htab_dt_scan_page_sizes(unsigned long node,
const char *uname, int depth,
void *data)
{
const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const __be32 *prop;
int size = 0;
/* We are scanning "cpu" nodes only */
if (type == NULL || strcmp(type, "cpu") != 0)
return 0;
prop = of_get_flat_dt_prop(node, "ibm,segment-page-sizes", &size);
if (!prop)
return 0;
pr_info("Page sizes from device-tree:\n");
size /= 4;
cur_cpu_spec->mmu_features &= ~(MMU_FTR_16M_PAGE);
while(size > 0) {
unsigned int base_shift = be32_to_cpu(prop[0]);
unsigned int slbenc = be32_to_cpu(prop[1]);
unsigned int lpnum = be32_to_cpu(prop[2]);
struct mmu_psize_def *def;
int idx, base_idx;
size -= 3; prop += 3;
base_idx = get_idx_from_shift(base_shift);
if (base_idx < 0) {
/* skip the pte encoding also */
prop += lpnum * 2; size -= lpnum * 2;
continue;
}
def = &mmu_psize_defs[base_idx];
if (base_idx == MMU_PAGE_16M)
cur_cpu_spec->mmu_features |= MMU_FTR_16M_PAGE;
def->shift = base_shift;
if (base_shift <= 23)
def->avpnm = 0;
else
def->avpnm = (1 << (base_shift - 23)) - 1;
def->sllp = slbenc;
/*
* We don't know for sure what's up with tlbiel, so
* for now we only set it for 4K and 64K pages
*/
if (base_idx == MMU_PAGE_4K || base_idx == MMU_PAGE_64K)
def->tlbiel = 1;
else
def->tlbiel = 0;
while (size > 0 && lpnum) {
unsigned int shift = be32_to_cpu(prop[0]);
int penc = be32_to_cpu(prop[1]);
prop += 2; size -= 2;
lpnum--;
idx = get_idx_from_shift(shift);
if (idx < 0)
continue;
if (penc == -1)
pr_err("Invalid penc for base_shift=%d "
"shift=%d\n", base_shift, shift);
def->penc[idx] = penc;
pr_info("base_shift=%d: shift=%d, sllp=0x%04lx,"
" avpnm=0x%08lx, tlbiel=%d, penc=%d\n",
base_shift, shift, def->sllp,
def->avpnm, def->tlbiel, def->penc[idx]);
}
}
return 1;
}
#ifdef CONFIG_HUGETLB_PAGE
/* Scan for 16G memory blocks that have been set aside for huge pages
* and reserve those blocks for 16G huge pages.
*/
static int __init htab_dt_scan_hugepage_blocks(unsigned long node,
const char *uname, int depth,
void *data) {
const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const __be64 *addr_prop;
const __be32 *page_count_prop;
unsigned int expected_pages;
long unsigned int phys_addr;
long unsigned int block_size;
/* We are scanning "memory" nodes only */
if (type == NULL || strcmp(type, "memory") != 0)
return 0;
/* This property is the log base 2 of the number of virtual pages that
* will represent this memory block. */
page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL);
if (page_count_prop == NULL)
return 0;
expected_pages = (1 << be32_to_cpu(page_count_prop[0]));
addr_prop = of_get_flat_dt_prop(node, "reg", NULL);
if (addr_prop == NULL)
return 0;
phys_addr = be64_to_cpu(addr_prop[0]);
block_size = be64_to_cpu(addr_prop[1]);
if (block_size != (16 * GB))
return 0;
printk(KERN_INFO "Huge page(16GB) memory: "
"addr = 0x%lX size = 0x%lX pages = %d\n",
phys_addr, block_size, expected_pages);
if (phys_addr + block_size * expected_pages <= memblock_end_of_DRAM()) {
memblock_reserve(phys_addr, block_size * expected_pages);
pseries_add_gpage(phys_addr, block_size, expected_pages);
}
return 0;
}
#endif /* CONFIG_HUGETLB_PAGE */
static void mmu_psize_set_default_penc(void)
{
int bpsize, apsize;
for (bpsize = 0; bpsize < MMU_PAGE_COUNT; bpsize++)
for (apsize = 0; apsize < MMU_PAGE_COUNT; apsize++)
mmu_psize_defs[bpsize].penc[apsize] = -1;
}
#ifdef CONFIG_PPC_64K_PAGES
static bool might_have_hea(void)
{
/*
* The HEA ethernet adapter requires awareness of the
* GX bus. Without that awareness we can easily assume
* we will never see an HEA ethernet device.
*/
#ifdef CONFIG_IBMEBUS
return !cpu_has_feature(CPU_FTR_ARCH_207S) &&
firmware_has_feature(FW_FEATURE_SPLPAR);
#else
return false;
#endif
}
#endif /* #ifdef CONFIG_PPC_64K_PAGES */
static void __init htab_scan_page_sizes(void)
{
int rc;
/* se the invalid penc to -1 */
mmu_psize_set_default_penc();
/* Default to 4K pages only */
memcpy(mmu_psize_defs, mmu_psize_defaults_old,
sizeof(mmu_psize_defaults_old));
/*
* Try to find the available page sizes in the device-tree
*/
rc = of_scan_flat_dt(htab_dt_scan_page_sizes, NULL);
if (rc == 0 && early_mmu_has_feature(MMU_FTR_16M_PAGE)) {
/*
* Nothing in the device-tree, but the CPU supports 16M pages,
* so let's fallback on a known size list for 16M capable CPUs.
*/
memcpy(mmu_psize_defs, mmu_psize_defaults_gp,
sizeof(mmu_psize_defaults_gp));
}
#ifdef CONFIG_HUGETLB_PAGE
/* Reserve 16G huge page memory sections for huge pages */
of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
#endif /* CONFIG_HUGETLB_PAGE */
}
/*
* Fill in the hpte_page_sizes[] array.
* We go through the mmu_psize_defs[] array looking for all the
* supported base/actual page size combinations. Each combination
* has a unique pagesize encoding (penc) value in the low bits of
* the LP field of the HPTE. For actual page sizes less than 1MB,
* some of the upper LP bits are used for RPN bits, meaning that
* we need to fill in several entries in hpte_page_sizes[].
*
* In diagrammatic form, with r = RPN bits and z = page size bits:
* PTE LP actual page size
* rrrr rrrz >=8KB
* rrrr rrzz >=16KB
* rrrr rzzz >=32KB
* rrrr zzzz >=64KB
* ...
*
* The zzzz bits are implementation-specific but are chosen so that
* no encoding for a larger page size uses the same value in its
* low-order N bits as the encoding for the 2^(12+N) byte page size
* (if it exists).
*/
static void init_hpte_page_sizes(void)
{
long int ap, bp;
long int shift, penc;
for (bp = 0; bp < MMU_PAGE_COUNT; ++bp) {
if (!mmu_psize_defs[bp].shift)
continue; /* not a supported page size */
for (ap = bp; ap < MMU_PAGE_COUNT; ++ap) {
penc = mmu_psize_defs[bp].penc[ap];
if (penc == -1)
continue;
shift = mmu_psize_defs[ap].shift - LP_SHIFT;
if (shift <= 0)
continue; /* should never happen */
/*
* For page sizes less than 1MB, this loop
* replicates the entry for all possible values
* of the rrrr bits.
*/
while (penc < (1 << LP_BITS)) {
hpte_page_sizes[penc] = (ap << 4) | bp;
penc += 1 << shift;
}
}
}
}
static void __init htab_init_page_sizes(void)
{
init_hpte_page_sizes();
if (!debug_pagealloc_enabled()) {
/*
* Pick a size for the linear mapping. Currently, we only
* support 16M, 1M and 4K which is the default
*/
if (mmu_psize_defs[MMU_PAGE_16M].shift)
mmu_linear_psize = MMU_PAGE_16M;
else if (mmu_psize_defs[MMU_PAGE_1M].shift)
mmu_linear_psize = MMU_PAGE_1M;
}
#ifdef CONFIG_PPC_64K_PAGES
/*
* Pick a size for the ordinary pages. Default is 4K, we support
* 64K for user mappings and vmalloc if supported by the processor.
* We only use 64k for ioremap if the processor
* (and firmware) support cache-inhibited large pages.
* If not, we use 4k and set mmu_ci_restrictions so that
* hash_page knows to switch processes that use cache-inhibited
* mappings to 4k pages.
*/
if (mmu_psize_defs[MMU_PAGE_64K].shift) {
mmu_virtual_psize = MMU_PAGE_64K;
mmu_vmalloc_psize = MMU_PAGE_64K;
if (mmu_linear_psize == MMU_PAGE_4K)
mmu_linear_psize = MMU_PAGE_64K;
if (mmu_has_feature(MMU_FTR_CI_LARGE_PAGE)) {
/*
* When running on pSeries using 64k pages for ioremap
* would stop us accessing the HEA ethernet. So if we
* have the chance of ever seeing one, stay at 4k.
*/
if (!might_have_hea())
mmu_io_psize = MMU_PAGE_64K;
} else
mmu_ci_restrictions = 1;
}
#endif /* CONFIG_PPC_64K_PAGES */
#ifdef CONFIG_SPARSEMEM_VMEMMAP
/* We try to use 16M pages for vmemmap if that is supported
* and we have at least 1G of RAM at boot
*/
if (mmu_psize_defs[MMU_PAGE_16M].shift &&
memblock_phys_mem_size() >= 0x40000000)
mmu_vmemmap_psize = MMU_PAGE_16M;
else if (mmu_psize_defs[MMU_PAGE_64K].shift)
mmu_vmemmap_psize = MMU_PAGE_64K;
else
mmu_vmemmap_psize = MMU_PAGE_4K;
#endif /* CONFIG_SPARSEMEM_VMEMMAP */
printk(KERN_DEBUG "Page orders: linear mapping = %d, "
"virtual = %d, io = %d"
#ifdef CONFIG_SPARSEMEM_VMEMMAP
", vmemmap = %d"
#endif
"\n",
mmu_psize_defs[mmu_linear_psize].shift,
mmu_psize_defs[mmu_virtual_psize].shift,
mmu_psize_defs[mmu_io_psize].shift
#ifdef CONFIG_SPARSEMEM_VMEMMAP
,mmu_psize_defs[mmu_vmemmap_psize].shift
#endif
);
}
static int __init htab_dt_scan_pftsize(unsigned long node,
const char *uname, int depth,
void *data)
{
const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const __be32 *prop;
/* We are scanning "cpu" nodes only */
if (type == NULL || strcmp(type, "cpu") != 0)
return 0;
prop = of_get_flat_dt_prop(node, "ibm,pft-size", NULL);
if (prop != NULL) {
/* pft_size[0] is the NUMA CEC cookie */
ppc64_pft_size = be32_to_cpu(prop[1]);
return 1;
}
return 0;
}
unsigned htab_shift_for_mem_size(unsigned long mem_size)
{
unsigned memshift = __ilog2(mem_size);
unsigned pshift = mmu_psize_defs[mmu_virtual_psize].shift;
unsigned pteg_shift;
/* round mem_size up to next power of 2 */
if ((1UL << memshift) < mem_size)
memshift += 1;
/* aim for 2 pages / pteg */
pteg_shift = memshift - (pshift + 1);
/*
* 2^11 PTEGS of 128 bytes each, ie. 2^18 bytes is the minimum htab
* size permitted by the architecture.
*/
return max(pteg_shift + 7, 18U);
}
static unsigned long __init htab_get_table_size(void)
{
/* If hash size isn't already provided by the platform, we try to
* retrieve it from the device-tree. If it's not there neither, we
* calculate it now based on the total RAM size
*/
if (ppc64_pft_size == 0)
of_scan_flat_dt(htab_dt_scan_pftsize, NULL);
if (ppc64_pft_size)
return 1UL << ppc64_pft_size;
return 1UL << htab_shift_for_mem_size(memblock_phys_mem_size());
}
#ifdef CONFIG_MEMORY_HOTPLUG
void resize_hpt_for_hotplug(unsigned long new_mem_size)
{
unsigned target_hpt_shift;
if (!mmu_hash_ops.resize_hpt)
return;
target_hpt_shift = htab_shift_for_mem_size(new_mem_size);
/*
* To avoid lots of HPT resizes if memory size is fluctuating
* across a boundary, we deliberately have some hysterisis
* here: we immediately increase the HPT size if the target
* shift exceeds the current shift, but we won't attempt to
* reduce unless the target shift is at least 2 below the
* current shift
*/
if ((target_hpt_shift > ppc64_pft_size)
|| (target_hpt_shift < (ppc64_pft_size - 1))) {
int rc;
rc = mmu_hash_ops.resize_hpt(target_hpt_shift);
if (rc)
printk(KERN_WARNING
"Unable to resize hash page table to target order %d: %d\n",
target_hpt_shift, rc);
}
}
int hash__create_section_mapping(unsigned long start, unsigned long end)
{
int rc = htab_bolt_mapping(start, end, __pa(start),
pgprot_val(PAGE_KERNEL), mmu_linear_psize,
mmu_kernel_ssize);
if (rc < 0) {
int rc2 = htab_remove_mapping(start, end, mmu_linear_psize,
mmu_kernel_ssize);
BUG_ON(rc2 && (rc2 != -ENOENT));
}
return rc;
}
int hash__remove_section_mapping(unsigned long start, unsigned long end)
{
int rc = htab_remove_mapping(start, end, mmu_linear_psize,
mmu_kernel_ssize);
WARN_ON(rc < 0);
return rc;
}
#endif /* CONFIG_MEMORY_HOTPLUG */
static void update_hid_for_hash(void)
{
unsigned long hid0;
unsigned long rb = 3UL << PPC_BITLSHIFT(53); /* IS = 3 */
asm volatile("ptesync": : :"memory");
/* prs = 0, ric = 2, rs = 0, r = 1 is = 3 */
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(0), "i"(0), "i"(2), "r"(0) : "memory");
asm volatile("eieio; tlbsync; ptesync; isync; slbia": : :"memory");
trace_tlbie(0, 0, rb, 0, 2, 0, 0);
/*
* now switch the HID
*/
hid0 = mfspr(SPRN_HID0);
hid0 &= ~HID0_POWER9_RADIX;
mtspr(SPRN_HID0, hid0);
asm volatile("isync": : :"memory");
/* Wait for it to happen */
while ((mfspr(SPRN_HID0) & HID0_POWER9_RADIX))
cpu_relax();
}
static void __init hash_init_partition_table(phys_addr_t hash_table,
unsigned long htab_size)
{
mmu_partition_table_init();
/*
* PS field (VRMA page size) is not used for LPID 0, hence set to 0.
* For now, UPRT is 0 and we have no segment table.
*/
htab_size = __ilog2(htab_size) - 18;
mmu_partition_table_set_entry(0, hash_table | htab_size, 0);
pr_info("Partition table %p\n", partition_tb);
if (cpu_has_feature(CPU_FTR_POWER9_DD1))
update_hid_for_hash();
}
static void __init htab_initialize(void)
{
unsigned long table;
unsigned long pteg_count;
unsigned long prot;
unsigned long base = 0, size = 0;
struct memblock_region *reg;
DBG(" -> htab_initialize()\n");
if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) {
mmu_kernel_ssize = MMU_SEGSIZE_1T;
mmu_highuser_ssize = MMU_SEGSIZE_1T;
printk(KERN_INFO "Using 1TB segments\n");
}
/*
* Calculate the required size of the htab. We want the number of
* PTEGs to equal one half the number of real pages.
*/
htab_size_bytes = htab_get_table_size();
pteg_count = htab_size_bytes >> 7;
htab_hash_mask = pteg_count - 1;
if (firmware_has_feature(FW_FEATURE_LPAR) ||
firmware_has_feature(FW_FEATURE_PS3_LV1)) {
/* Using a hypervisor which owns the htab */
htab_address = NULL;
_SDR1 = 0;
#ifdef CONFIG_FA_DUMP
/*
* If firmware assisted dump is active firmware preserves
* the contents of htab along with entire partition memory.
* Clear the htab if firmware assisted dump is active so
* that we dont end up using old mappings.
*/
if (is_fadump_active() && mmu_hash_ops.hpte_clear_all)
mmu_hash_ops.hpte_clear_all();
#endif
} else {
unsigned long limit = MEMBLOCK_ALLOC_ANYWHERE;
#ifdef CONFIG_PPC_CELL
/*
* Cell may require the hash table down low when using the
* Axon IOMMU in order to fit the dynamic region over it, see
* comments in cell/iommu.c
*/
if (fdt_subnode_offset(initial_boot_params, 0, "axon") > 0) {
limit = 0x80000000;
pr_info("Hash table forced below 2G for Axon IOMMU\n");
}
#endif /* CONFIG_PPC_CELL */
table = memblock_alloc_base(htab_size_bytes, htab_size_bytes,
limit);
DBG("Hash table allocated at %lx, size: %lx\n", table,
htab_size_bytes);
htab_address = __va(table);
/* htab absolute addr + encoded htabsize */
_SDR1 = table + __ilog2(htab_size_bytes) - 18;
/* Initialize the HPT with no entries */
memset((void *)table, 0, htab_size_bytes);
if (!cpu_has_feature(CPU_FTR_ARCH_300))
/* Set SDR1 */
mtspr(SPRN_SDR1, _SDR1);
else
hash_init_partition_table(table, htab_size_bytes);
}
prot = pgprot_val(PAGE_KERNEL);
#ifdef CONFIG_DEBUG_PAGEALLOC
if (debug_pagealloc_enabled()) {
linear_map_hash_count = memblock_end_of_DRAM() >> PAGE_SHIFT;
linear_map_hash_slots = __va(memblock_alloc_base(
linear_map_hash_count, 1, ppc64_rma_size));
memset(linear_map_hash_slots, 0, linear_map_hash_count);
}
#endif /* CONFIG_DEBUG_PAGEALLOC */
/* create bolted the linear mapping in the hash table */
for_each_memblock(memory, reg) {
base = (unsigned long)__va(reg->base);
size = reg->size;
DBG("creating mapping for region: %lx..%lx (prot: %lx)\n",
base, size, prot);
BUG_ON(htab_bolt_mapping(base, base + size, __pa(base),
prot, mmu_linear_psize, mmu_kernel_ssize));
}
memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE);
/*
* If we have a memory_limit and we've allocated TCEs then we need to
* explicitly map the TCE area at the top of RAM. We also cope with the
* case that the TCEs start below memory_limit.
* tce_alloc_start/end are 16MB aligned so the mapping should work
* for either 4K or 16MB pages.
*/
if (tce_alloc_start) {
tce_alloc_start = (unsigned long)__va(tce_alloc_start);
tce_alloc_end = (unsigned long)__va(tce_alloc_end);
if (base + size >= tce_alloc_start)
tce_alloc_start = base + size + 1;
BUG_ON(htab_bolt_mapping(tce_alloc_start, tce_alloc_end,
__pa(tce_alloc_start), prot,
mmu_linear_psize, mmu_kernel_ssize));
}
DBG(" <- htab_initialize()\n");
}
#undef KB
#undef MB
void __init hash__early_init_devtree(void)
{
/* Initialize segment sizes */
of_scan_flat_dt(htab_dt_scan_seg_sizes, NULL);
/* Initialize page sizes */
htab_scan_page_sizes();
}
void __init hash__early_init_mmu(void)
{
#ifndef CONFIG_PPC_64K_PAGES
/*
* We have code in __hash_page_4K() and elsewhere, which assumes it can
* do the following:
* new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX);
*
* Where the slot number is between 0-15, and values of 8-15 indicate
* the secondary bucket. For that code to work H_PAGE_F_SECOND and
* H_PAGE_F_GIX must occupy four contiguous bits in the PTE, and
* H_PAGE_F_SECOND must be placed above H_PAGE_F_GIX. Assert that here
* with a BUILD_BUG_ON().
*/
BUILD_BUG_ON(H_PAGE_F_SECOND != (1ul << (H_PAGE_F_GIX_SHIFT + 3)));
#endif /* CONFIG_PPC_64K_PAGES */
htab_init_page_sizes();
/*
* initialize page table size
*/
__pte_frag_nr = H_PTE_FRAG_NR;
__pte_frag_size_shift = H_PTE_FRAG_SIZE_SHIFT;
__pte_index_size = H_PTE_INDEX_SIZE;
__pmd_index_size = H_PMD_INDEX_SIZE;
__pud_index_size = H_PUD_INDEX_SIZE;
__pgd_index_size = H_PGD_INDEX_SIZE;
__pmd_cache_index = H_PMD_CACHE_INDEX;
__pte_table_size = H_PTE_TABLE_SIZE;
__pmd_table_size = H_PMD_TABLE_SIZE;
__pud_table_size = H_PUD_TABLE_SIZE;
__pgd_table_size = H_PGD_TABLE_SIZE;
/*
* 4k use hugepd format, so for hash set then to
* zero
*/
__pmd_val_bits = 0;
__pud_val_bits = 0;
__pgd_val_bits = 0;
__kernel_virt_start = H_KERN_VIRT_START;
__kernel_virt_size = H_KERN_VIRT_SIZE;
__vmalloc_start = H_VMALLOC_START;
__vmalloc_end = H_VMALLOC_END;
__kernel_io_start = H_KERN_IO_START;
vmemmap = (struct page *)H_VMEMMAP_BASE;
ioremap_bot = IOREMAP_BASE;
#ifdef CONFIG_PCI
pci_io_base = ISA_IO_BASE;
#endif
/* Select appropriate backend */
if (firmware_has_feature(FW_FEATURE_PS3_LV1))
ps3_early_mm_init();
else if (firmware_has_feature(FW_FEATURE_LPAR))
hpte_init_pseries();
else if (IS_ENABLED(CONFIG_PPC_NATIVE))
hpte_init_native();
if (!mmu_hash_ops.hpte_insert)
panic("hash__early_init_mmu: No MMU hash ops defined!\n");
/* Initialize the MMU Hash table and create the linear mapping
* of memory. Has to be done before SLB initialization as this is
* currently where the page size encoding is obtained.
*/
htab_initialize();
pr_info("Initializing hash mmu with SLB\n");
/* Initialize SLB management */
slb_initialize();
if (cpu_has_feature(CPU_FTR_ARCH_206)
&& cpu_has_feature(CPU_FTR_HVMODE))
tlbiel_all();
}
#ifdef CONFIG_SMP
void hash__early_init_mmu_secondary(void)
{
/* Initialize hash table for that CPU */
if (!firmware_has_feature(FW_FEATURE_LPAR)) {
if (cpu_has_feature(CPU_FTR_POWER9_DD1))
update_hid_for_hash();
if (!cpu_has_feature(CPU_FTR_ARCH_300))
mtspr(SPRN_SDR1, _SDR1);
else
mtspr(SPRN_PTCR,
__pa(partition_tb) | (PATB_SIZE_SHIFT - 12));
}
/* Initialize SLB */
slb_initialize();
if (cpu_has_feature(CPU_FTR_ARCH_206)
&& cpu_has_feature(CPU_FTR_HVMODE))
tlbiel_all();
}
#endif /* CONFIG_SMP */
/*
* Called by asm hashtable.S for doing lazy icache flush
*/
unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
{
struct page *page;
if (!pfn_valid(pte_pfn(pte)))
return pp;
page = pte_page(pte);
/* page is dirty */
if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
if (trap == 0x400) {
flush_dcache_icache_page(page);
set_bit(PG_arch_1, &page->flags);
} else
pp |= HPTE_R_N;
}
return pp;
}
#ifdef CONFIG_PPC_MM_SLICES
static unsigned int get_paca_psize(unsigned long addr)
{
u64 lpsizes;
unsigned char *hpsizes;
unsigned long index, mask_index;
if (addr < SLICE_LOW_TOP) {
lpsizes = get_paca()->mm_ctx_low_slices_psize;
index = GET_LOW_SLICE_INDEX(addr);
return (lpsizes >> (index * 4)) & 0xF;
}
hpsizes = get_paca()->mm_ctx_high_slices_psize;
index = GET_HIGH_SLICE_INDEX(addr);
mask_index = index & 0x1;
return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xF;
}
#else
unsigned int get_paca_psize(unsigned long addr)
{
return get_paca()->mm_ctx_user_psize;
}
#endif
/*
* Demote a segment to using 4k pages.
* For now this makes the whole process use 4k pages.
*/
#ifdef CONFIG_PPC_64K_PAGES
void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
{
if (get_slice_psize(mm, addr) == MMU_PAGE_4K)
return;
slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K);
copro_flush_all_slbs(mm);
if ((get_paca_psize(addr) != MMU_PAGE_4K) && (current->mm == mm)) {
copy_mm_to_paca(mm);
slb_flush_and_rebolt();
}
}
#endif /* CONFIG_PPC_64K_PAGES */
#ifdef CONFIG_PPC_SUBPAGE_PROT
/*
* This looks up a 2-bit protection code for a 4k subpage of a 64k page.
* Userspace sets the subpage permissions using the subpage_prot system call.
*
* Result is 0: full permissions, _PAGE_RW: read-only,
* _PAGE_RWX: no access.
*/
static int subpage_protection(struct mm_struct *mm, unsigned long ea)
{
struct subpage_prot_table *spt = &mm->context.spt;
u32 spp = 0;
u32 **sbpm, *sbpp;
if (ea >= spt->maxaddr)
return 0;
if (ea < 0x100000000UL) {
/* addresses below 4GB use spt->low_prot */
sbpm = spt->low_prot;
} else {
sbpm = spt->protptrs[ea >> SBP_L3_SHIFT];
if (!sbpm)
return 0;
}
sbpp = sbpm[(ea >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1)];
if (!sbpp)
return 0;
spp = sbpp[(ea >> PAGE_SHIFT) & (SBP_L1_COUNT - 1)];
/* extract 2-bit bitfield for this 4k subpage */
spp >>= 30 - 2 * ((ea >> 12) & 0xf);
/*
* 0 -> full premission
* 1 -> Read only
* 2 -> no access.
* We return the flag that need to be cleared.
*/
spp = ((spp & 2) ? _PAGE_RWX : 0) | ((spp & 1) ? _PAGE_WRITE : 0);
return spp;
}
#else /* CONFIG_PPC_SUBPAGE_PROT */
static inline int subpage_protection(struct mm_struct *mm, unsigned long ea)
{
return 0;
}
#endif
void hash_failure_debug(unsigned long ea, unsigned long access,
unsigned long vsid, unsigned long trap,
int ssize, int psize, int lpsize, unsigned long pte)
{
if (!printk_ratelimit())
return;
pr_info("mm: Hashing failure ! EA=0x%lx access=0x%lx current=%s\n",
ea, access, current->comm);
pr_info(" trap=0x%lx vsid=0x%lx ssize=%d base psize=%d psize %d pte=0x%lx\n",
trap, vsid, ssize, psize, lpsize, pte);
}
static void check_paca_psize(unsigned long ea, struct mm_struct *mm,
int psize, bool user_region)
{
if (user_region) {
if (psize != get_paca_psize(ea)) {
copy_mm_to_paca(mm);
slb_flush_and_rebolt();
}
} else if (get_paca()->vmalloc_sllp !=
mmu_psize_defs[mmu_vmalloc_psize].sllp) {
get_paca()->vmalloc_sllp =
mmu_psize_defs[mmu_vmalloc_psize].sllp;
slb_vmalloc_update();
}
}
/* Result code is:
* 0 - handled
* 1 - normal page fault
* -1 - critical hash insertion error
* -2 - access not permitted by subpage protection mechanism
*/
int hash_page_mm(struct mm_struct *mm, unsigned long ea,
unsigned long access, unsigned long trap,
unsigned long flags)
{
bool is_thp;
enum ctx_state prev_state = exception_enter();
pgd_t *pgdir;
unsigned long vsid;
pte_t *ptep;
unsigned hugeshift;
int rc, user_region = 0;
int psize, ssize;
DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n",
ea, access, trap);
trace_hash_fault(ea, access, trap);
/* Get region & vsid */
switch (REGION_ID(ea)) {
case USER_REGION_ID:
user_region = 1;
if (! mm) {
DBG_LOW(" user region with no mm !\n");
rc = 1;
goto bail;
}
psize = get_slice_psize(mm, ea);
ssize = user_segment_size(ea);
vsid = get_vsid(mm->context.id, ea, ssize);
break;
case VMALLOC_REGION_ID:
vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
if (ea < VMALLOC_END)
psize = mmu_vmalloc_psize;
else
psize = mmu_io_psize;
ssize = mmu_kernel_ssize;
break;
default:
/* Not a valid range
* Send the problem up to do_page_fault
*/
rc = 1;
goto bail;
}
DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid);
/* Bad address. */
if (!vsid) {
DBG_LOW("Bad address!\n");
rc = 1;
goto bail;
}
/* Get pgdir */
pgdir = mm->pgd;
if (pgdir == NULL) {
rc = 1;
goto bail;
}
/* Check CPU locality */
if (user_region && mm_is_thread_local(mm))
flags |= HPTE_LOCAL_UPDATE;
#ifndef CONFIG_PPC_64K_PAGES
/* If we use 4K pages and our psize is not 4K, then we might
* be hitting a special driver mapping, and need to align the
* address before we fetch the PTE.
*
* It could also be a hugepage mapping, in which case this is
* not necessary, but it's not harmful, either.
*/
if (psize != MMU_PAGE_4K)
ea &= ~((1ul << mmu_psize_defs[psize].shift) - 1);
#endif /* CONFIG_PPC_64K_PAGES */
/* Get PTE and page size from page tables */
ptep = find_linux_pte(pgdir, ea, &is_thp, &hugeshift);
if (ptep == NULL || !pte_present(*ptep)) {
DBG_LOW(" no PTE !\n");
rc = 1;
goto bail;
}
/* Add _PAGE_PRESENT to the required access perm */
access |= _PAGE_PRESENT;
/* Pre-check access permissions (will be re-checked atomically
* in __hash_page_XX but this pre-check is a fast path
*/
if (!check_pte_access(access, pte_val(*ptep))) {
DBG_LOW(" no access !\n");
rc = 1;
goto bail;
}
if (hugeshift) {
if (is_thp)
rc = __hash_page_thp(ea, access, vsid, (pmd_t *)ptep,
trap, flags, ssize, psize);
#ifdef CONFIG_HUGETLB_PAGE
else
rc = __hash_page_huge(ea, access, vsid, ptep, trap,
flags, ssize, hugeshift, psize);
#else
else {
/*
* if we have hugeshift, and is not transhuge with
* hugetlb disabled, something is really wrong.
*/
rc = 1;
WARN_ON(1);
}
#endif
if (current->mm == mm)
check_paca_psize(ea, mm, psize, user_region);
goto bail;
}
#ifndef CONFIG_PPC_64K_PAGES
DBG_LOW(" i-pte: %016lx\n", pte_val(*ptep));
#else
DBG_LOW(" i-pte: %016lx %016lx\n", pte_val(*ptep),
pte_val(*(ptep + PTRS_PER_PTE)));
#endif
/* Do actual hashing */
#ifdef CONFIG_PPC_64K_PAGES
/* If H_PAGE_4K_PFN is set, make sure this is a 4k segment */
if ((pte_val(*ptep) & H_PAGE_4K_PFN) && psize == MMU_PAGE_64K) {
demote_segment_4k(mm, ea);
psize = MMU_PAGE_4K;
}
/* If this PTE is non-cacheable and we have restrictions on
* using non cacheable large pages, then we switch to 4k
*/
if (mmu_ci_restrictions && psize == MMU_PAGE_64K && pte_ci(*ptep)) {
if (user_region) {
demote_segment_4k(mm, ea);
psize = MMU_PAGE_4K;
} else if (ea < VMALLOC_END) {
/*
* some driver did a non-cacheable mapping
* in vmalloc space, so switch vmalloc
* to 4k pages
*/
printk(KERN_ALERT "Reducing vmalloc segment "
"to 4kB pages because of "
"non-cacheable mapping\n");
psize = mmu_vmalloc_psize = MMU_PAGE_4K;
copro_flush_all_slbs(mm);
}
}
#endif /* CONFIG_PPC_64K_PAGES */
if (current->mm == mm)
check_paca_psize(ea, mm, psize, user_region);
#ifdef CONFIG_PPC_64K_PAGES
if (psize == MMU_PAGE_64K)
rc = __hash_page_64K(ea, access, vsid, ptep, trap,
flags, ssize);
else
#endif /* CONFIG_PPC_64K_PAGES */
{
int spp = subpage_protection(mm, ea);
if (access & spp)
rc = -2;
else
rc = __hash_page_4K(ea, access, vsid, ptep, trap,
flags, ssize, spp);
}
/* Dump some info in case of hash insertion failure, they should
* never happen so it is really useful to know if/when they do
*/
if (rc == -1)
hash_failure_debug(ea, access, vsid, trap, ssize, psize,
psize, pte_val(*ptep));
#ifndef CONFIG_PPC_64K_PAGES
DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep));
#else
DBG_LOW(" o-pte: %016lx %016lx\n", pte_val(*ptep),
pte_val(*(ptep + PTRS_PER_PTE)));
#endif
DBG_LOW(" -> rc=%d\n", rc);
bail:
exception_exit(prev_state);
return rc;
}
EXPORT_SYMBOL_GPL(hash_page_mm);
int hash_page(unsigned long ea, unsigned long access, unsigned long trap,
unsigned long dsisr)
{
unsigned long flags = 0;
struct mm_struct *mm = current->mm;
if (REGION_ID(ea) == VMALLOC_REGION_ID)
mm = &init_mm;
if (dsisr & DSISR_NOHPTE)
flags |= HPTE_NOHPTE_UPDATE;
return hash_page_mm(mm, ea, access, trap, flags);
}
EXPORT_SYMBOL_GPL(hash_page);
int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap,
unsigned long dsisr)
{
unsigned long access = _PAGE_PRESENT | _PAGE_READ;
unsigned long flags = 0;
struct mm_struct *mm = current->mm;
if (REGION_ID(ea) == VMALLOC_REGION_ID)
mm = &init_mm;
if (dsisr & DSISR_NOHPTE)
flags |= HPTE_NOHPTE_UPDATE;
if (dsisr & DSISR_ISSTORE)
access |= _PAGE_WRITE;
/*
* We set _PAGE_PRIVILEGED only when
* kernel mode access kernel space.
*
* _PAGE_PRIVILEGED is NOT set
* 1) when kernel mode access user space
* 2) user space access kernel space.
*/
access |= _PAGE_PRIVILEGED;
if ((msr & MSR_PR) || (REGION_ID(ea) == USER_REGION_ID))
access &= ~_PAGE_PRIVILEGED;
if (trap == 0x400)
access |= _PAGE_EXEC;
return hash_page_mm(mm, ea, access, trap, flags);
}
#ifdef CONFIG_PPC_MM_SLICES
static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
{
int psize = get_slice_psize(mm, ea);
/* We only prefault standard pages for now */
if (unlikely(psize != mm->context.user_psize))
return false;
/*
* Don't prefault if subpage protection is enabled for the EA.
*/
if (unlikely((psize == MMU_PAGE_4K) && subpage_protection(mm, ea)))
return false;
return true;
}
#else
static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
{
return true;
}
#endif
void hash_preload(struct mm_struct *mm, unsigned long ea,
unsigned long access, unsigned long trap)
{
int hugepage_shift;
unsigned long vsid;
pgd_t *pgdir;
pte_t *ptep;
unsigned long flags;
int rc, ssize, update_flags = 0;
BUG_ON(REGION_ID(ea) != USER_REGION_ID);
if (!should_hash_preload(mm, ea))
return;
DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx,"
" trap=%lx\n", mm, mm->pgd, ea, access, trap);
/* Get Linux PTE if available */
pgdir = mm->pgd;
if (pgdir == NULL)
return;
/* Get VSID */
ssize = user_segment_size(ea);
vsid = get_vsid(mm->context.id, ea, ssize);
if (!vsid)
return;
/*
* Hash doesn't like irqs. Walking linux page table with irq disabled
* saves us from holding multiple locks.
*/
local_irq_save(flags);
/*
* THP pages use update_mmu_cache_pmd. We don't do
* hash preload there. Hence can ignore THP here
*/
ptep = find_current_mm_pte(pgdir, ea, NULL, &hugepage_shift);
if (!ptep)
goto out_exit;
WARN_ON(hugepage_shift);
#ifdef CONFIG_PPC_64K_PAGES
/* If either H_PAGE_4K_PFN or cache inhibited is set (and we are on
* a 64K kernel), then we don't preload, hash_page() will take
* care of it once we actually try to access the page.
* That way we don't have to duplicate all of the logic for segment
* page size demotion here
*/
if ((pte_val(*ptep) & H_PAGE_4K_PFN) || pte_ci(*ptep))
goto out_exit;
#endif /* CONFIG_PPC_64K_PAGES */
/* Is that local to this CPU ? */
if (mm_is_thread_local(mm))
update_flags |= HPTE_LOCAL_UPDATE;
/* Hash it in */
#ifdef CONFIG_PPC_64K_PAGES
if (mm->context.user_psize == MMU_PAGE_64K)
rc = __hash_page_64K(ea, access, vsid, ptep, trap,
update_flags, ssize);
else
#endif /* CONFIG_PPC_64K_PAGES */
rc = __hash_page_4K(ea, access, vsid, ptep, trap, update_flags,
ssize, subpage_protection(mm, ea));
/* Dump some info in case of hash insertion failure, they should
* never happen so it is really useful to know if/when they do
*/
if (rc == -1)
hash_failure_debug(ea, access, vsid, trap, ssize,
mm->context.user_psize,
mm->context.user_psize,
pte_val(*ptep));
out_exit:
local_irq_restore(flags);
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
static inline void tm_flush_hash_page(int local)
{
/*
* Transactions are not aborted by tlbiel, only tlbie. Without, syncing a
* page back to a block device w/PIO could pick up transactional data
* (bad!) so we force an abort here. Before the sync the page will be
* made read-only, which will flush_hash_page. BIG ISSUE here: if the
* kernel uses a page from userspace without unmapping it first, it may
* see the speculated version.
*/
if (local && cpu_has_feature(CPU_FTR_TM) && current->thread.regs &&
MSR_TM_ACTIVE(current->thread.regs->msr)) {
tm_enable();
tm_abort(TM_CAUSE_TLBI);
}
}
#else
static inline void tm_flush_hash_page(int local)
{
}
#endif
/*
* Return the global hash slot, corresponding to the given PTE, which contains
* the HPTE.
*/
unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift,
int ssize, real_pte_t rpte, unsigned int subpg_index)
{
unsigned long hash, gslot, hidx;
hash = hpt_hash(vpn, shift, ssize);
hidx = __rpte_to_hidx(rpte, subpg_index);
if (hidx & _PTEIDX_SECONDARY)
hash = ~hash;
gslot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
gslot += hidx & _PTEIDX_GROUP_IX;
return gslot;
}
/* WARNING: This is called from hash_low_64.S, if you change this prototype,
* do not forget to update the assembly call site !
*/
void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize,
unsigned long flags)
{
unsigned long index, shift, gslot;
int local = flags & HPTE_LOCAL_UPDATE;
DBG_LOW("flush_hash_page(vpn=%016lx)\n", vpn);
pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) {
gslot = pte_get_hash_gslot(vpn, shift, ssize, pte, index);
DBG_LOW(" sub %ld: gslot=%lx\n", index, gslot);
/*
* We use same base page size and actual psize, because we don't
* use these functions for hugepage
*/
mmu_hash_ops.hpte_invalidate(gslot, vpn, psize, psize,
ssize, local);
} pte_iterate_hashed_end();
tm_flush_hash_page(local);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void flush_hash_hugepage(unsigned long vsid, unsigned long addr,
pmd_t *pmdp, unsigned int psize, int ssize,
unsigned long flags)
{
int i, max_hpte_count, valid;
unsigned long s_addr;
unsigned char *hpte_slot_array;
unsigned long hidx, shift, vpn, hash, slot;
int local = flags & HPTE_LOCAL_UPDATE;
s_addr = addr & HPAGE_PMD_MASK;
hpte_slot_array = get_hpte_slot_array(pmdp);
/*
* IF we try to do a HUGE PTE update after a withdraw is done.
* we will find the below NULL. This happens when we do
* split_huge_page_pmd
*/
if (!hpte_slot_array)
return;
if (mmu_hash_ops.hugepage_invalidate) {
mmu_hash_ops.hugepage_invalidate(vsid, s_addr, hpte_slot_array,
psize, ssize, local);
goto tm_abort;
}
/*
* No bluk hpte removal support, invalidate each entry
*/
shift = mmu_psize_defs[psize].shift;
max_hpte_count = HPAGE_PMD_SIZE >> shift;
for (i = 0; i < max_hpte_count; i++) {
/*
* 8 bits per each hpte entries
* 000| [ secondary group (one bit) | hidx (3 bits) | valid bit]
*/
valid = hpte_valid(hpte_slot_array, i);
if (!valid)
continue;
hidx = hpte_hash_index(hpte_slot_array, i);
/* get the vpn */
addr = s_addr + (i * (1ul << shift));
vpn = hpt_vpn(addr, vsid, ssize);
hash = hpt_hash(vpn, shift, ssize);
if (hidx & _PTEIDX_SECONDARY)
hash = ~hash;
slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
slot += hidx & _PTEIDX_GROUP_IX;
mmu_hash_ops.hpte_invalidate(slot, vpn, psize,
MMU_PAGE_16M, ssize, local);
}
tm_abort:
tm_flush_hash_page(local);
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
void flush_hash_range(unsigned long number, int local)
{
if (mmu_hash_ops.flush_hash_range)
mmu_hash_ops.flush_hash_range(number, local);
else {
int i;
struct ppc64_tlb_batch *batch =
this_cpu_ptr(&ppc64_tlb_batch);
for (i = 0; i < number; i++)
flush_hash_page(batch->vpn[i], batch->pte[i],
batch->psize, batch->ssize, local);
}
}
/*
* low_hash_fault is called when we the low level hash code failed
* to instert a PTE due to an hypervisor error
*/
void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc)
{
enum ctx_state prev_state = exception_enter();
if (user_mode(regs)) {
#ifdef CONFIG_PPC_SUBPAGE_PROT
if (rc == -2)
_exception(SIGSEGV, regs, SEGV_ACCERR, address);
else
#endif
_exception(SIGBUS, regs, BUS_ADRERR, address);
} else
bad_page_fault(regs, address, SIGBUS);
exception_exit(prev_state);
}
long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
unsigned long pa, unsigned long rflags,
unsigned long vflags, int psize, int ssize)
{
unsigned long hpte_group;
long slot;
repeat:
hpte_group = ((hash & htab_hash_mask) *
HPTES_PER_GROUP) & ~0x7UL;
/* Insert into the hash table, primary slot */
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, vflags,
psize, psize, ssize);
/* Primary is full, try the secondary */
if (unlikely(slot == -1)) {
hpte_group = ((~hash & htab_hash_mask) *
HPTES_PER_GROUP) & ~0x7UL;
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags,
vflags | HPTE_V_SECONDARY,
psize, psize, ssize);
if (slot == -1) {
if (mftb() & 0x1)
hpte_group = ((hash & htab_hash_mask) *
HPTES_PER_GROUP)&~0x7UL;
mmu_hash_ops.hpte_remove(hpte_group);
goto repeat;
}
}
return slot;
}
#ifdef CONFIG_DEBUG_PAGEALLOC
static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi)
{
unsigned long hash;
unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize);
unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize);
unsigned long mode = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL));
long ret;
hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize);
/* Don't create HPTE entries for bad address */
if (!vsid)
return;
ret = hpte_insert_repeating(hash, vpn, __pa(vaddr), mode,
HPTE_V_BOLTED,
mmu_linear_psize, mmu_kernel_ssize);
BUG_ON (ret < 0);
spin_lock(&linear_map_hash_lock);
BUG_ON(linear_map_hash_slots[lmi] & 0x80);
linear_map_hash_slots[lmi] = ret | 0x80;
spin_unlock(&linear_map_hash_lock);
}
static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi)
{
unsigned long hash, hidx, slot;
unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize);
unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize);
hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize);
spin_lock(&linear_map_hash_lock);
BUG_ON(!(linear_map_hash_slots[lmi] & 0x80));
hidx = linear_map_hash_slots[lmi] & 0x7f;
linear_map_hash_slots[lmi] = 0;
spin_unlock(&linear_map_hash_lock);
if (hidx & _PTEIDX_SECONDARY)
hash = ~hash;
slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
slot += hidx & _PTEIDX_GROUP_IX;
mmu_hash_ops.hpte_invalidate(slot, vpn, mmu_linear_psize,
mmu_linear_psize,
mmu_kernel_ssize, 0);
}
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
unsigned long flags, vaddr, lmi;
int i;
local_irq_save(flags);
for (i = 0; i < numpages; i++, page++) {
vaddr = (unsigned long)page_address(page);
lmi = __pa(vaddr) >> PAGE_SHIFT;
if (lmi >= linear_map_hash_count)
continue;
if (enable)
kernel_map_linear_page(vaddr, lmi);
else
kernel_unmap_linear_page(vaddr, lmi);
}
local_irq_restore(flags);
}
#endif /* CONFIG_DEBUG_PAGEALLOC */
void hash__setup_initial_memory_limit(phys_addr_t first_memblock_base,
phys_addr_t first_memblock_size)
{
/* We don't currently support the first MEMBLOCK not mapping 0
* physical on those processors
*/
BUG_ON(first_memblock_base != 0);
/*
* On virtualized systems the first entry is our RMA region aka VRMA,
* non-virtualized 64-bit hash MMU systems don't have a limitation
* on real mode access.
*
* For guests on platforms before POWER9, we clamp the it limit to 1G
* to avoid some funky things such as RTAS bugs etc...
*/
if (!early_cpu_has_feature(CPU_FTR_HVMODE)) {
ppc64_rma_size = first_memblock_size;
if (!early_cpu_has_feature(CPU_FTR_ARCH_300))
ppc64_rma_size = min_t(u64, ppc64_rma_size, 0x40000000);
/* Finally limit subsequent allocations */
memblock_set_current_limit(ppc64_rma_size);
} else {
ppc64_rma_size = ULONG_MAX;
}
}
#ifdef CONFIG_DEBUG_FS
static int hpt_order_get(void *data, u64 *val)
{
*val = ppc64_pft_size;
return 0;
}
static int hpt_order_set(void *data, u64 val)
{
if (!mmu_hash_ops.resize_hpt)
return -ENODEV;
return mmu_hash_ops.resize_hpt(val);
}
DEFINE_SIMPLE_ATTRIBUTE(fops_hpt_order, hpt_order_get, hpt_order_set, "%llu\n");
static int __init hash64_debugfs(void)
{
if (!debugfs_create_file("hpt_order", 0600, powerpc_debugfs_root,
NULL, &fops_hpt_order)) {
pr_err("lpar: unable to create hpt_order debugsfs file\n");
}
return 0;
}
machine_device_initcall(pseries, hash64_debugfs);
#endif /* CONFIG_DEBUG_FS */
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