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Commit 89ff7250 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Michael Ellerman
Browse files

powerpc/mm: Convert __hash_page_64K to C

parent 227fdbee
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+2 −1
Original line number Diff line number Diff line
@@ -40,7 +40,8 @@
#define _PAGE_COMBO_VALID	(_PAGE_F_GIX | _PAGE_F_SECOND)

/* PTE flags to conserve for HPTE identification */
#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_COMBO)
#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_F_SECOND | \
			 _PAGE_F_GIX | _PAGE_HASHPTE | _PAGE_COMBO)

/* Shift to put page number into pte.
 *
+130 −0
Original line number Diff line number Diff line
@@ -229,3 +229,133 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
	*ptep = __pte(new_pte & ~_PAGE_BUSY);
	return 0;
}

int __hash_page_64K(unsigned long ea, unsigned long access,
		    unsigned long vsid, pte_t *ptep, unsigned long trap,
		    unsigned long flags, int ssize)
{

	unsigned long hpte_group;
	unsigned long rflags, pa;
	unsigned long old_pte, new_pte;
	unsigned long vpn, hash, slot;
	unsigned long shift = mmu_psize_defs[MMU_PAGE_64K].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;
		/*
		 * Check if PTE has the cache-inhibit bit set
		 * If so, bail out and refault as a 4k page
		 */
		if (!mmu_has_feature(MMU_FTR_CI_LARGE_PAGE) &&
		    unlikely(old_pte & _PAGE_NO_CACHE))
			return 0;
		/*
		 * 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;
		if (access & _PAGE_RW)
			new_pte |= _PAGE_DIRTY;
	} while (old_pte != __cmpxchg_u64((unsigned long *)ptep,
					  old_pte, new_pte));
	/*
	 * 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 = new_pte & _PAGE_USER;
	if ((new_pte & _PAGE_USER) && !((new_pte & _PAGE_RW) &&
					(new_pte & _PAGE_DIRTY)))
		rflags |= 0x1;
	/*
	 * _PAGE_EXEC -> HW_NO_EXEC since it's inverted
	 */
	rflags |= ((new_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 |= (new_pte & (_PAGE_WRITETHRU | _PAGE_NO_CACHE |
				_PAGE_COHERENT | _PAGE_GUARDED));

	if (!cpu_has_feature(CPU_FTR_NOEXECUTE) &&
	    !cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
		rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap);

	vpn  = hpt_vpn(ea, vsid, ssize);
	if (unlikely(old_pte & _PAGE_HASHPTE)) {
		/*
		 * There MIGHT be an HPTE for this pte
		 */
		hash = hpt_hash(vpn, shift, ssize);
		if (old_pte & _PAGE_F_SECOND)
			hash = ~hash;
		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
		slot += (old_pte & _PAGE_F_GIX) >> _PAGE_F_GIX_SHIFT;

		if (ppc_md.hpte_updatepp(slot, rflags, vpn, MMU_PAGE_64K,
					 MMU_PAGE_64K, ssize, flags) == -1)
			old_pte &= ~_PAGE_HPTEFLAGS;
	}

	if (likely(!(old_pte & _PAGE_HASHPTE))) {

		pa = pte_pfn(__pte(old_pte)) << PAGE_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_64K, MMU_PAGE_64K, 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_64K, MMU_PAGE_64K, 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_64K, MMU_PAGE_64K, old_pte);
			return -1;
		}
		new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE;
		new_pte |= (slot << _PAGE_F_GIX_SHIFT) & (_PAGE_F_SECOND | _PAGE_F_GIX);
	}
	*ptep = __pte(new_pte & ~_PAGE_BUSY);
	return 0;
}
+1 −289
Original line number Diff line number Diff line
@@ -328,292 +328,4 @@ htab_pte_insert_failure:
	li	r3,-1
	b	htab_bail

#else /* CONFIG_PPC_64K_PAGES */

/*****************************************************************************
 *                                                                           *
 *           64K SW & 64K HW in a 64K segment pages implementation           *
 *                                                                           *
 *****************************************************************************/

_GLOBAL(__hash_page_64K)
	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 ?)
	 */
	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-	ht64_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-	ht64_bail_ok
BEGIN_FTR_SECTION
	/* Check if PTE has the cache-inhibit bit set */
	andi.	r0,r31,_PAGE_NO_CACHE
	/* If so, bail out and refault as a 4k page */
	bne-	ht64_bail_ok
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_CI_LARGE_PAGE)
	/* 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
	/* 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
	 */

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
	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 >> 16) & ((1ul << (28 - 16)) -1)
	 */
	rldicl	r0,r3,64-16,52
	xor	r28,r5,r0		/* hash */
	b	4f

3:	/* Calc vpn and put it in r29 */
	sldi	r29,r5,SID_SHIFT_1T - 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 >> 16) & ((1ul << (40 - 16)) -1) */
	rldicl	r0,r3,64-16,40
	xor	r28,r28,r5		/* vsid ^ ( vsid << 25) */
	xor	r28,r28,r0		/* hash */

	/* Convert linux PTE bits into HW equivalents */
4:	andi.	r3,r30,0x1fe		/* Get basic set of flags */
	xori	r3,r3,HPTE_R_N		/* _PAGE_EXEC -> NOEXEC */
	rlwinm	r0,r30,32-9+1,30,30	/* _PAGE_RW -> _PAGE_USER (r0) */
	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,r30,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
	 */
	rldicl.	r0,r31,64-12,48
	bne	ht64_modify_pte

ht64_insert_pte:
	/* Clear hpte bits in new pte (we also clear BUSY btw) and
	 * add _PAGE_HPTE_SUB0
	 */
	lis	r0,_PAGE_HPTEFLAGS@h
	ori	r0,r0,_PAGE_HPTEFLAGS@l
	andc	r30,r30,r0
	ori	r30,r30,_PAGE_HASHPTE
	/* Phyical address in r5 */
	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
	sldi	r5,r5,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_64K
	li	r9,MMU_PAGE_64K		/* actual page size */
	ld	r10,STK_PARAM(R9)(r1)	/* segment size */
.globl ht64_call_hpte_insert1
ht64_call_hpte_insert1:
	bl	.			/* patched by htab_finish_init() */
	cmpdi	0,r3,0
	bge	ht64_pte_insert_ok	/* Insertion successful */
	cmpdi	0,r3,-2			/* Critical failure */
	beq-	ht64_pte_insert_failure

	/* Now try secondary slot */

	/* Phyical address in r5 */
	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
	sldi	r5,r5,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_64K
	li	r9,MMU_PAGE_64K		/* actual page size */
	ld	r10,STK_PARAM(R9)(r1)	/* segment size */
.globl ht64_call_hpte_insert2
ht64_call_hpte_insert2:
	bl	.			/* patched by htab_finish_init() */
	cmpdi	0,r3,0
	bge+	ht64_pte_insert_ok	/* Insertion successful */
	cmpdi	0,r3,-2			/* Critical failure */
	beq-	ht64_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 ht64_call_hpte_remove
ht64_call_hpte_remove:
	bl	.			/* patched by htab_finish_init() */

	/* Try all again */
	b	ht64_insert_pte

ht64_bail_ok:
	li	r3,0
	b	ht64_bail

ht64_pte_insert_ok:
	/* Insert slot number & secondary bit in PTE */
	rldimi	r30,r3,12,63-15

	/* Write out the PTE with a normal write
	 * (maybe add eieio may be good still ?)
	 */
ht64_write_out_pte:
	ld	r6,STK_PARAM(R6)(r1)
	std	r30,0(r6)
	li	r3, 0
ht64_bail:
	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

ht64_modify_pte:
	/* Keep PP bits in r4 and slot idx from the PTE around in r3 */
	mr	r4,r3
	rlwinm	r3,r31,32-12,29,31

	/* Secondary group ? if yes, get a inverted hash value */
	mr	r5,r28
	andi.	r0,r31,_PAGE_F_SECOND
	beq	1f
	not	r5,r5
1:
	/* 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_64K		/* base page size */
	li	r7,MMU_PAGE_64K		/* actual page size */
	ld	r8,STK_PARAM(R9)(r1)	/* segment size */
	ld	r9,STK_PARAM(R8)(r1)	/* get "flags" param */
.globl ht64_call_hpte_updatepp
ht64_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-	ht64_insert_pte

	/* Clear the BUSY bit and Write out the PTE */
	li	r0,_PAGE_BUSY
	andc	r30,r30,r0
	b	ht64_write_out_pte

ht64_wrong_access:
	/* Bail out clearing reservation */
	stdcx.	r31,0,r6
	li	r3,1
	b	ht64_bail

ht64_pte_insert_failure:
	/* Bail out restoring old PTE */
	ld	r6,STK_PARAM(R6)(r1)
	std	r31,0(r6)
	li	r3,-1
	b	ht64_bail


#endif /* CONFIG_PPC_64K_PAGES */
#endif
+1 −18
Original line number Diff line number Diff line
@@ -633,28 +633,11 @@ extern u32 htab_call_hpte_insert1[];
extern u32 htab_call_hpte_insert2[];
extern u32 htab_call_hpte_remove[];
extern u32 htab_call_hpte_updatepp[];
extern u32 ht64_call_hpte_insert1[];
extern u32 ht64_call_hpte_insert2[];
extern u32 ht64_call_hpte_remove[];
extern u32 ht64_call_hpte_updatepp[];

static void __init htab_finish_init(void)
{
#ifdef CONFIG_PPC_64K_PAGES
	patch_branch(ht64_call_hpte_insert1,
		ppc_function_entry(ppc_md.hpte_insert),
		BRANCH_SET_LINK);
	patch_branch(ht64_call_hpte_insert2,
		ppc_function_entry(ppc_md.hpte_insert),
		BRANCH_SET_LINK);
	patch_branch(ht64_call_hpte_remove,
		ppc_function_entry(ppc_md.hpte_remove),
		BRANCH_SET_LINK);
	patch_branch(ht64_call_hpte_updatepp,
		ppc_function_entry(ppc_md.hpte_updatepp),
		BRANCH_SET_LINK);
#else /* !CONFIG_PPC_64K_PAGES */

#ifdef CONFIG_PPC_4K_PAGES
	patch_branch(htab_call_hpte_insert1,
		ppc_function_entry(ppc_md.hpte_insert),
		BRANCH_SET_LINK);