powerpc/mm: Convert 4k hash insert to C

Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Aneesh Kumar K.V 2015-12-01 09:06:43 +05:30 committed by Michael Ellerman
parent 17ed9e3192
commit 91f1da9979
4 changed files with 208 additions and 381 deletions

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@ -18,6 +18,9 @@ obj-$(CONFIG_PPC_STD_MMU_32) += ppc_mmu_32.o
obj-$(CONFIG_PPC_STD_MMU) += hash_low_$(CONFIG_WORD_SIZE).o \
tlb_hash$(CONFIG_WORD_SIZE).o \
mmu_context_hash$(CONFIG_WORD_SIZE).o
ifeq ($(CONFIG_PPC_STD_MMU_64),y)
obj-$(CONFIG_PPC_64K_PAGES) += hash64_64k.o
endif
obj-$(CONFIG_PPC_ICSWX) += icswx.o
obj-$(CONFIG_PPC_ICSWX_PID) += icswx_pid.o
obj-$(CONFIG_40x) += 40x_mmu.o

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@ -0,0 +1,202 @@
/*
* Copyright IBM Corporation, 2015
* Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU Lesser General Public License
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
*/
#include <linux/mm.h>
#include <asm/machdep.h>
#include <asm/mmu.h>
int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
pte_t *ptep, unsigned long trap, unsigned long flags,
int ssize, int subpg_prot)
{
real_pte_t rpte;
unsigned long *hidxp;
unsigned long hpte_group;
unsigned int subpg_index;
unsigned long rflags, pa, hidx;
unsigned long old_pte, new_pte, subpg_pte;
unsigned long vpn, hash, slot;
unsigned long shift = mmu_psize_defs[MMU_PAGE_4K].shift;
/*
* atomically mark the linux large page PTE busy and dirty
*/
do {
pte_t pte = READ_ONCE(*ptep);
old_pte = pte_val(pte);
/* If PTE busy, retry the access */
if (unlikely(old_pte & _PAGE_BUSY))
return 0;
/* If PTE permissions don't match, take page fault */
if (unlikely(access & ~old_pte))
return 1;
/*
* Try to lock the PTE, add ACCESSED and DIRTY if it was
* a write access. Since this is 4K insert of 64K page size
* also add _PAGE_COMBO
*/
new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED | _PAGE_COMBO;
if (access & _PAGE_RW)
new_pte |= _PAGE_DIRTY;
} while (old_pte != __cmpxchg_u64((unsigned long *)ptep,
old_pte, new_pte));
/*
* Handle the subpage protection bits
*/
subpg_pte = new_pte & ~subpg_prot;
/*
* PP bits. _PAGE_USER is already PP bit 0x2, so we only
* need to add in 0x1 if it's a read-only user page
*/
rflags = subpg_pte & _PAGE_USER;
if ((subpg_pte & _PAGE_USER) && !((subpg_pte & _PAGE_RW) &&
(subpg_pte & _PAGE_DIRTY)))
rflags |= 0x1;
/*
* _PAGE_EXEC -> HW_NO_EXEC since it's inverted
*/
rflags |= ((subpg_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
/*
* Always add C and Memory coherence bit
*/
rflags |= HPTE_R_C | HPTE_R_M;
/*
* Add in WIMG bits
*/
rflags |= (subpg_pte & (_PAGE_WRITETHRU | _PAGE_NO_CACHE |
_PAGE_COHERENT | _PAGE_GUARDED));
if (!cpu_has_feature(CPU_FTR_NOEXECUTE) &&
!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
/*
* No CPU has hugepages but lacks no execute, so we
* don't need to worry about that case
*/
rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap);
}
subpg_index = (ea & (PAGE_SIZE - 1)) >> shift;
vpn = hpt_vpn(ea, vsid, ssize);
rpte = __real_pte(__pte(old_pte), ptep);
/*
*None of the sub 4k page is hashed
*/
if (!(old_pte & _PAGE_HASHPTE))
goto htab_insert_hpte;
/*
* Check if the pte was already inserted into the hash table
* as a 64k HW page, and invalidate the 64k HPTE if so.
*/
if (!(old_pte & _PAGE_COMBO)) {
flush_hash_page(vpn, rpte, MMU_PAGE_64K, ssize, flags);
old_pte &= ~_PAGE_HPTE_SUB;
goto htab_insert_hpte;
}
/*
* Check for sub page valid and update
*/
if (__rpte_sub_valid(rpte, subpg_index)) {
int ret;
hash = hpt_hash(vpn, shift, ssize);
hidx = __rpte_to_hidx(rpte, subpg_index);
if (hidx & _PTEIDX_SECONDARY)
hash = ~hash;
slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
slot += hidx & _PTEIDX_GROUP_IX;
ret = ppc_md.hpte_updatepp(slot, rflags, vpn,
MMU_PAGE_4K, MMU_PAGE_4K,
ssize, flags);
/*
*if we failed because typically the HPTE wasn't really here
* we try an insertion.
*/
if (ret == -1)
goto htab_insert_hpte;
*ptep = __pte(new_pte & ~_PAGE_BUSY);
return 0;
}
htab_insert_hpte:
/*
* handle _PAGE_4K_PFN case
*/
if (old_pte & _PAGE_4K_PFN) {
/*
* All the sub 4k page have the same
* physical address.
*/
pa = pte_pfn(__pte(old_pte)) << HW_PAGE_SHIFT;
} else {
pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
pa += (subpg_index << shift);
}
hash = hpt_hash(vpn, shift, ssize);
repeat:
hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
/* Insert into the hash table, primary slot */
slot = ppc_md.hpte_insert(hpte_group, vpn, pa, rflags, 0,
MMU_PAGE_4K, MMU_PAGE_4K, ssize);
/*
* Primary is full, try the secondary
*/
if (unlikely(slot == -1)) {
hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
slot = ppc_md.hpte_insert(hpte_group, vpn, pa,
rflags, HPTE_V_SECONDARY,
MMU_PAGE_4K, MMU_PAGE_4K, ssize);
if (slot == -1) {
if (mftb() & 0x1)
hpte_group = ((hash & htab_hash_mask) *
HPTES_PER_GROUP) & ~0x7UL;
ppc_md.hpte_remove(hpte_group);
/*
* FIXME!! Should be try the group from which we removed ?
*/
goto repeat;
}
}
/*
* Hypervisor failure. Restore old pmd and return -1
* similar to __hash_page_*
*/
if (unlikely(slot == -2)) {
*ptep = __pte(old_pte);
hash_failure_debug(ea, access, vsid, trap, ssize,
MMU_PAGE_4K, MMU_PAGE_4K, old_pte);
return -1;
}
/*
* Insert slot number & secondary bit in PTE second half,
* clear _PAGE_BUSY and set appropriate HPTE slot bit
* Since we have _PAGE_BUSY set on ptep, we can be sure
* nobody is undating hidx.
*/
hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
/* __real_pte use pte_val() any idea why ? FIXME!! */
rpte.hidx &= ~(0xfUL << (subpg_index << 2));
*hidxp = rpte.hidx | (slot << (subpg_index << 2));
new_pte |= (_PAGE_HPTE_SUB0 >> subpg_index);
/*
* check __real_pte for details on matching smp_rmb()
*/
smp_wmb();
*ptep = __pte(new_pte & ~_PAGE_BUSY);
return 0;
}

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@ -328,381 +328,8 @@ htab_pte_insert_failure:
li r3,-1
b htab_bail
#else /* CONFIG_PPC_64K_PAGES */
/*****************************************************************************
* *
* 64K SW & 4K or 64K HW in a 4K segment pages implementation *
* *
*****************************************************************************/
/* _hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* pte_t *ptep, unsigned long trap, unsigned local flags,
* int ssize, int subpg_prot)
*/
/*
* For now, we do NOT implement Admixed pages
*/
_GLOBAL(__hash_page_4K)
mflr r0
std r0,16(r1)
stdu r1,-STACKFRAMESIZE(r1)
/* Save all params that we need after a function call */
std r6,STK_PARAM(R6)(r1)
std r8,STK_PARAM(R8)(r1)
std r9,STK_PARAM(R9)(r1)
/* Save non-volatile registers.
* r31 will hold "old PTE"
* r30 is "new PTE"
* r29 is vpn
* r28 is a hash value
* r27 is hashtab mask (maybe dynamic patched instead ?)
* r26 is the hidx mask
* r25 is the index in combo page
*/
std r25,STK_REG(R25)(r1)
std r26,STK_REG(R26)(r1)
std r27,STK_REG(R27)(r1)
std r28,STK_REG(R28)(r1)
std r29,STK_REG(R29)(r1)
std r30,STK_REG(R30)(r1)
std r31,STK_REG(R31)(r1)
/* Step 1:
*
* Check permissions, atomically mark the linux PTE busy
* and hashed.
*/
1:
ldarx r31,0,r6
/* Check access rights (access & ~(pte_val(*ptep))) */
andc. r0,r4,r31
bne- htab_wrong_access
/* Check if PTE is busy */
andi. r0,r31,_PAGE_BUSY
/* If so, just bail out and refault if needed. Someone else
* is changing this PTE anyway and might hash it.
*/
bne- htab_bail_ok
/* Prepare new PTE value (turn access RW into DIRTY, then
* add BUSY and ACCESSED)
*/
rlwinm r30,r4,32-9+7,31-7,31-7 /* _PAGE_RW -> _PAGE_DIRTY */
or r30,r30,r31
ori r30,r30,_PAGE_BUSY | _PAGE_ACCESSED
oris r30,r30,_PAGE_COMBO@h
/* Write the linux PTE atomically (setting busy) */
stdcx. r30,0,r6
bne- 1b
isync
/* Step 2:
*
* Insert/Update the HPTE in the hash table. At this point,
* r4 (access) is re-useable, we use it for the new HPTE flags
*/
/* Load the hidx index */
rldicl r25,r3,64-12,60
BEGIN_FTR_SECTION
cmpdi r9,0 /* check segment size */
bne 3f
END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
/* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT - VPN_SHIFT
/*
* clrldi r3,r3,64 - SID_SHIFT --> ea & 0xfffffff
* srdi r28,r3,VPN_SHIFT
*/
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT - VPN_SHIFT)
or r29,r28,r29
/*
* Calculate hash value for primary slot and store it in r28
* r3 = va, r5 = vsid
* r0 = (va >> 12) & ((1ul << (28 - 12)) -1)
*/
rldicl r0,r3,64-12,48
xor r28,r5,r0 /* hash */
b 4f
3: /* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT_1T - VPN_SHIFT
/*
* clrldi r3,r3,64 - SID_SHIFT_1T --> ea & 0xffffffffff
* srdi r28,r3,VPN_SHIFT
*/
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT_1T - VPN_SHIFT)
or r29,r28,r29
/*
* Calculate hash value for primary slot and
* store it in r28 for 1T segment
* r3 = va, r5 = vsid
*/
sldi r28,r5,25 /* vsid << 25 */
/* r0 = (va >> 12) & ((1ul << (40 - 12)) -1) */
rldicl r0,r3,64-12,36
xor r28,r28,r5 /* vsid ^ ( vsid << 25) */
xor r28,r28,r0 /* hash */
/* Convert linux PTE bits into HW equivalents */
4:
#ifdef CONFIG_PPC_SUBPAGE_PROT
andc r10,r30,r10
andi. r3,r10,0x1fe /* Get basic set of flags */
rlwinm r0,r10,32-9+1,30,30 /* _PAGE_RW -> _PAGE_USER (r0) */
#else
andi. r3,r30,0x1fe /* Get basic set of flags */
rlwinm r0,r30,32-9+1,30,30 /* _PAGE_RW -> _PAGE_USER (r0) */
#endif
xori r3,r3,HPTE_R_N /* _PAGE_EXEC -> NOEXEC */
rlwinm r4,r30,32-7+1,30,30 /* _PAGE_DIRTY -> _PAGE_USER (r4) */
and r0,r0,r4 /* _PAGE_RW & _PAGE_DIRTY ->r0 bit 30*/
andc r0,r3,r0 /* r0 = pte & ~r0 */
rlwimi r3,r0,32-1,31,31 /* Insert result into PP lsb */
/*
* Always add "C" bit for perf. Memory coherence is always enabled
*/
ori r3,r3,HPTE_R_C | HPTE_R_M
/* We eventually do the icache sync here (maybe inline that
* code rather than call a C function...)
*/
BEGIN_FTR_SECTION
mr r4,r30
mr r5,r7
bl hash_page_do_lazy_icache
END_FTR_SECTION(CPU_FTR_NOEXECUTE|CPU_FTR_COHERENT_ICACHE, CPU_FTR_NOEXECUTE)
/* At this point, r3 contains new PP bits, save them in
* place of "access" in the param area (sic)
*/
std r3,STK_PARAM(R4)(r1)
/* Get htab_hash_mask */
ld r4,htab_hash_mask@got(2)
ld r27,0(r4) /* htab_hash_mask -> r27 */
/* Check if we may already be in the hashtable, in this case, we
* go to out-of-line code to try to modify the HPTE. We look for
* the bit at (1 >> (index + 32))
*/
rldicl. r0,r31,64-12,48
li r26,0 /* Default hidx */
beq htab_insert_pte
/*
* Check if the pte was already inserted into the hash table
* as a 64k HW page, and invalidate the 64k HPTE if so.
*/
andis. r0,r31,_PAGE_COMBO@h
beq htab_inval_old_hpte
ld r6,STK_PARAM(R6)(r1)
ori r26,r6,PTE_PAGE_HIDX_OFFSET /* Load the hidx mask. */
ld r26,0(r26)
addi r5,r25,36 /* Check actual HPTE_SUB bit, this */
rldcr. r0,r31,r5,0 /* must match pgtable.h definition */
bne htab_modify_pte
htab_insert_pte:
/* real page number in r5, PTE RPN value + index */
andis. r0,r31,_PAGE_4K_PFN@h
srdi r5,r31,PTE_RPN_SHIFT
bne- htab_special_pfn
sldi r5,r5,PAGE_FACTOR
add r5,r5,r25
htab_special_pfn:
sldi r5,r5,HW_PAGE_SHIFT
/* Calculate primary group hash */
and r0,r28,r27
rldicr r3,r0,3,63-3 /* r0 = (hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,0 /* !bolted, !secondary */
li r8,MMU_PAGE_4K /* page size */
li r9,MMU_PAGE_4K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl htab_call_hpte_insert1
htab_call_hpte_insert1:
bl . /* patched by htab_finish_init() */
cmpdi 0,r3,0
bge htab_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- htab_pte_insert_failure
/* Now try secondary slot */
/* real page number in r5, PTE RPN value + index */
andis. r0,r31,_PAGE_4K_PFN@h
srdi r5,r31,PTE_RPN_SHIFT
bne- 3f
sldi r5,r5,PAGE_FACTOR
add r5,r5,r25
3: sldi r5,r5,HW_PAGE_SHIFT
/* Calculate secondary group hash */
andc r0,r27,r28
rldicr r3,r0,3,63-3 /* r0 = (~hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,HPTE_V_SECONDARY /* !bolted, secondary */
li r8,MMU_PAGE_4K /* page size */
li r9,MMU_PAGE_4K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl htab_call_hpte_insert2
htab_call_hpte_insert2:
bl . /* patched by htab_finish_init() */
cmpdi 0,r3,0
bge+ htab_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- htab_pte_insert_failure
/* Both are full, we need to evict something */
mftb r0
/* Pick a random group based on TB */
andi. r0,r0,1
mr r5,r28
bne 2f
not r5,r5
2: and r0,r5,r27
rldicr r3,r0,3,63-3 /* r0 = (hash & mask) << 3 */
/* Call ppc_md.hpte_remove */
.globl htab_call_hpte_remove
htab_call_hpte_remove:
bl . /* patched by htab_finish_init() */
/* Try all again */
b htab_insert_pte
/*
* Call out to C code to invalidate an 64k HW HPTE that is
* useless now that the segment has been switched to 4k pages.
*/
htab_inval_old_hpte:
mr r3,r29 /* vpn */
mr r4,r31 /* PTE.pte */
li r5,0 /* PTE.hidx */
li r6,MMU_PAGE_64K /* psize */
ld r7,STK_PARAM(R9)(r1) /* ssize */
ld r8,STK_PARAM(R8)(r1) /* flags */
bl flush_hash_page
/* Clear out _PAGE_HPTE_SUB bits in the new linux PTE */
lis r0,_PAGE_HPTE_SUB@h
ori r0,r0,_PAGE_HPTE_SUB@l
andc r30,r30,r0
b htab_insert_pte
htab_bail_ok:
li r3,0
b htab_bail
htab_pte_insert_ok:
/* Insert slot number & secondary bit in PTE second half,
* clear _PAGE_BUSY and set approriate HPTE slot bit
*/
ld r6,STK_PARAM(R6)(r1)
li r0,_PAGE_BUSY
andc r30,r30,r0
/* HPTE SUB bit */
li r0,1
subfic r5,r25,27 /* Must match bit position in */
sld r0,r0,r5 /* pgtable.h */
or r30,r30,r0
/* hindx */
sldi r5,r25,2
sld r3,r3,r5
li r4,0xf
sld r4,r4,r5
andc r26,r26,r4
or r26,r26,r3
ori r5,r6,PTE_PAGE_HIDX_OFFSET
std r26,0(r5)
lwsync
std r30,0(r6)
li r3, 0
htab_bail:
ld r25,STK_REG(R25)(r1)
ld r26,STK_REG(R26)(r1)
ld r27,STK_REG(R27)(r1)
ld r28,STK_REG(R28)(r1)
ld r29,STK_REG(R29)(r1)
ld r30,STK_REG(R30)(r1)
ld r31,STK_REG(R31)(r1)
addi r1,r1,STACKFRAMESIZE
ld r0,16(r1)
mtlr r0
blr
htab_modify_pte:
/* Keep PP bits in r4 and slot idx from the PTE around in r3 */
mr r4,r3
sldi r5,r25,2
srd r3,r26,r5
/* Secondary group ? if yes, get a inverted hash value */
mr r5,r28
andi. r0,r3,0x8 /* page secondary ? */
beq 1f
not r5,r5
1: andi. r3,r3,0x7 /* extract idx alone */
/* Calculate proper slot value for ppc_md.hpte_updatepp */
and r0,r5,r27
rldicr r0,r0,3,63-3 /* r0 = (hash & mask) << 3 */
add r3,r0,r3 /* add slot idx */
/* Call ppc_md.hpte_updatepp */
mr r5,r29 /* vpn */
li r6,MMU_PAGE_4K /* base page size */
li r7,MMU_PAGE_4K /* actual page size */
ld r8,STK_PARAM(R9)(r1) /* segment size */
ld r9,STK_PARAM(R8)(r1) /* get "flags" param */
.globl htab_call_hpte_updatepp
htab_call_hpte_updatepp:
bl . /* patched by htab_finish_init() */
/* if we failed because typically the HPTE wasn't really here
* we try an insertion.
*/
cmpdi 0,r3,-1
beq- htab_insert_pte
/* Clear the BUSY bit and Write out the PTE */
li r0,_PAGE_BUSY
andc r30,r30,r0
ld r6,STK_PARAM(R6)(r1)
std r30,0(r6)
li r3,0
b htab_bail
htab_wrong_access:
/* Bail out clearing reservation */
stdcx. r31,0,r6
li r3,1
b htab_bail
htab_pte_insert_failure:
/* Bail out restoring old PTE */
ld r6,STK_PARAM(R6)(r1)
std r31,0(r6)
li r3,-1
b htab_bail
#endif /* CONFIG_PPC_64K_PAGES */
#ifdef CONFIG_PPC_64K_PAGES
/*****************************************************************************
* *
* 64K SW & 64K HW in a 64K segment pages implementation *
@ -994,10 +621,3 @@ ht64_pte_insert_failure:
#endif /* CONFIG_PPC_64K_PAGES */
/*****************************************************************************
* *
* Huge pages implementation is in hugetlbpage.c *
* *
*****************************************************************************/

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@ -653,7 +653,7 @@ static void __init htab_finish_init(void)
patch_branch(ht64_call_hpte_updatepp,
ppc_function_entry(ppc_md.hpte_updatepp),
BRANCH_SET_LINK);
#endif /* CONFIG_PPC_64K_PAGES */
#else /* !CONFIG_PPC_64K_PAGES */
patch_branch(htab_call_hpte_insert1,
ppc_function_entry(ppc_md.hpte_insert),
@ -667,6 +667,8 @@ static void __init htab_finish_init(void)
patch_branch(htab_call_hpte_updatepp,
ppc_function_entry(ppc_md.hpte_updatepp),
BRANCH_SET_LINK);
#endif
}
static void __init htab_initialize(void)