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-rw-r--r--arch/powerpc/mm/hash_low_64.S847
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diff --git a/arch/powerpc/mm/hash_low_64.S b/arch/powerpc/mm/hash_low_64.S
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+/*
+ * ppc64 MMU hashtable management routines
+ *
+ * (c) Copyright IBM Corp. 2003, 2005
+ *
+ * Maintained by: Benjamin Herrenschmidt
+ * <benh@kernel.crashing.org>
+ *
+ * This file is covered by the GNU Public Licence v2 as
+ * described in the kernel's COPYING file.
+ */
+
+#include <linux/config.h>
+#include <asm/reg.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/page.h>
+#include <asm/types.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/cputable.h>
+
+ .text
+
+/*
+ * Stackframe:
+ *
+ * +-> Back chain (SP + 256)
+ * | General register save area (SP + 112)
+ * | Parameter save area (SP + 48)
+ * | TOC save area (SP + 40)
+ * | link editor doubleword (SP + 32)
+ * | compiler doubleword (SP + 24)
+ * | LR save area (SP + 16)
+ * | CR save area (SP + 8)
+ * SP ---> +-- Back chain (SP + 0)
+ */
+#define STACKFRAMESIZE 256
+
+/* Save parameters offsets */
+#define STK_PARM(i) (STACKFRAMESIZE + 48 + ((i)-3)*8)
+
+/* Save non-volatile offsets */
+#define STK_REG(i) (112 + ((i)-14)*8)
+
+
+#ifndef CONFIG_PPC_64K_PAGES
+
+/*****************************************************************************
+ * *
+ * 4K SW & 4K HW pages implementation *
+ * *
+ *****************************************************************************/
+
+
+/*
+ * _hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
+ * pte_t *ptep, unsigned long trap, int local)
+ *
+ * Adds a 4K page to the hash table in a segment of 4K pages only
+ */
+
+_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_PARM(r6)(r1)
+ std r8,STK_PARM(r8)(r1)
+
+ /* Add _PAGE_PRESENT to access */
+ ori r4,r4,_PAGE_PRESENT
+
+ /* Save non-volatile registers.
+ * r31 will hold "old PTE"
+ * r30 is "new PTE"
+ * r29 is "va"
+ * 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- 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,HASHPTE 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 | _PAGE_HASHPTE
+ /* 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
+ */
+
+ /* Calc va and put it in r29 */
+ rldicr r29,r5,28,63-28
+ rldicl r3,r3,0,36
+ or r29,r3,r29
+
+ /* Calculate hash value for primary slot and store it in r28 */
+ rldicl r5,r5,0,25 /* vsid & 0x0000007fffffffff */
+ rldicl r0,r3,64-12,48 /* (ea >> 12) & 0xffff */
+ xor r28,r5,r0
+
+ /* Convert linux PTE bits into HW equivalents */
+ 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 */
+
+ /* 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_PARM(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
+ */
+ andi. r0,r31,_PAGE_HASHPTE
+ bne htab_modify_pte
+
+htab_insert_pte:
+ /* Clear hpte bits in new pte (we also clear BUSY btw) and
+ * add _PAGE_HASHPTE
+ */
+ lis r0,_PAGE_HPTEFLAGS@h
+ ori r0,r0,_PAGE_HPTEFLAGS@l
+ andc r30,r30,r0
+ ori r30,r30,_PAGE_HASHPTE
+
+ /* physical address 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 /* r3 = (hash & mask) << 3 */
+
+ /* Call ppc_md.hpte_insert */
+ ld r6,STK_PARM(r4)(r1) /* Retreive new pp bits */
+ mr r4,r29 /* Retreive va */
+ li r7,0 /* !bolted, !secondary */
+ li r8,MMU_PAGE_4K /* page size */
+_GLOBAL(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 */
+
+ /* physical address 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_PARM(r4)(r1) /* Retreive new pp bits */
+ mr r4,r29 /* Retreive va */
+ li r7,HPTE_V_SECONDARY /* !bolted, secondary */
+ li r8,MMU_PAGE_4K /* page size */
+_GLOBAL(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 */
+_GLOBAL(htab_call_hpte_remove)
+ bl . /* Patched by htab_finish_init() */
+
+ /* Try all again */
+ b htab_insert_pte
+
+htab_bail_ok:
+ li r3,0
+ b htab_bail
+
+htab_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 ?)
+ */
+htab_write_out_pte:
+ ld r6,STK_PARM(r6)(r1)
+ std r30,0(r6)
+ li r3, 0
+htab_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
+
+htab_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_SECONDARY
+ 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 /* va */
+ li r6,MMU_PAGE_4K /* page size */
+ ld r7,STK_PARM(r8)(r1) /* get "local" param */
+_GLOBAL(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
+ b htab_write_out_pte
+
+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_PARM(r6)(r1)
+ std r31,0(r6)
+ 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, int local)
+ */
+
+/*
+ * 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_PARM(r6)(r1)
+ std r8,STK_PARM(r8)(r1)
+
+ /* Add _PAGE_PRESENT to access */
+ ori r4,r4,_PAGE_PRESENT
+
+ /* Save non-volatile registers.
+ * r31 will hold "old PTE"
+ * r30 is "new PTE"
+ * r29 is "va"
+ * 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 | _PAGE_HASHPTE
+ /* 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
+
+ /* Calc va and put it in r29 */
+ rldicr r29,r5,28,63-28 /* r29 = (vsid << 28) */
+ rldicl r3,r3,0,36 /* r3 = (ea & 0x0fffffff) */
+ or r29,r3,r29 /* r29 = va
+
+ /* Calculate hash value for primary slot and store it in r28 */
+ rldicl r5,r5,0,25 /* vsid & 0x0000007fffffffff */
+ rldicl r0,r3,64-12,48 /* (ea >> 12) & 0xffff */
+ xor r28,r5,r0
+
+ /* Convert linux PTE bits into HW equivalents */
+ 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 */
+
+ /* 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_PARM(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))
+ */
+ andi. r0,r31,_PAGE_HASHPTE
+ li r26,0 /* Default hidx */
+ beq htab_insert_pte
+ ld r6,STK_PARM(r6)(r1)
+ ori r26,r6,0x8000 /* 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 */
+ rldicl r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+ sldi r5,r5,PAGE_SHIFT-HW_PAGE_SHIFT
+ add r5,r5,r25
+ 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_PARM(r4)(r1) /* Retreive new pp bits */
+ mr r4,r29 /* Retreive va */
+ li r7,0 /* !bolted, !secondary */
+ li r8,MMU_PAGE_4K /* page size */
+_GLOBAL(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 */
+ rldicl r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+ sldi r5,r5,PAGE_SHIFT-HW_PAGE_SHIFT
+ add r5,r5,r25
+ 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_PARM(r4)(r1) /* Retreive new pp bits */
+ mr r4,r29 /* Retreive va */
+ li r7,HPTE_V_SECONDARY /* !bolted, secondary */
+ li r8,MMU_PAGE_4K /* page size */
+_GLOBAL(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 */
+_GLOBAL(htab_call_hpte_remove)
+ bl . /* patched by htab_finish_init() */
+
+ /* Try all again */
+ 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_PARM(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,r6,0x8000
+ 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 /* va */
+ li r6,MMU_PAGE_4K /* page size */
+ ld r7,STK_PARM(r8)(r1) /* get "local" param */
+_GLOBAL(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_PARM(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_PARM(r6)(r1)
+ std r31,0(r6)
+ li r3,-1
+ b htab_bail
+
+
+/*****************************************************************************
+ * *
+ * 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_PARM(r6)(r1)
+ std r8,STK_PARM(r8)(r1)
+
+ /* Add _PAGE_PRESENT to access */
+ ori r4,r4,_PAGE_PRESENT
+
+ /* Save non-volatile registers.
+ * r31 will hold "old PTE"
+ * r30 is "new PTE"
+ * r29 is "va"
+ * 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
+ /* Prepare new PTE value (turn access RW into DIRTY, then
+ * add BUSY,HASHPTE 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 | _PAGE_HASHPTE
+ /* 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
+ */
+
+ /* Calc va and put it in r29 */
+ rldicr r29,r5,28,63-28
+ rldicl r3,r3,0,36
+ or r29,r3,r29
+
+ /* Calculate hash value for primary slot and store it in r28 */
+ rldicl r5,r5,0,25 /* vsid & 0x0000007fffffffff */
+ rldicl r0,r3,64-16,52 /* (ea >> 16) & 0xfff */
+ xor r28,r5,r0
+
+ /* Convert linux PTE bits into HW equivalents */
+ 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 */
+
+ /* 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_PARM(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
+ */
+ andi. r0,r31,_PAGE_HASHPTE
+ bne ht64_modify_pte
+
+ht64_insert_pte:
+ /* Clear hpte bits in new pte (we also clear BUSY btw) and
+ * add _PAGE_HASHPTE
+ */
+ 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_PARM(r4)(r1) /* Retreive new pp bits */
+ mr r4,r29 /* Retreive va */
+ li r7,0 /* !bolted, !secondary */
+ li r8,MMU_PAGE_64K
+_GLOBAL(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_PARM(r4)(r1) /* Retreive new pp bits */
+ mr r4,r29 /* Retreive va */
+ li r7,HPTE_V_SECONDARY /* !bolted, secondary */
+ li r8,MMU_PAGE_64K
+_GLOBAL(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 */
+_GLOBAL(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_PARM(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 /* va */
+ li r6,MMU_PAGE_64K
+ ld r7,STK_PARM(r8)(r1) /* get "local" param */
+_GLOBAL(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_PARM(r6)(r1)
+ std r31,0(r6)
+ li r3,-1
+ b ht64_bail
+
+
+#endif /* CONFIG_PPC_64K_PAGES */
+
+
+/*****************************************************************************
+ * *
+ * Huge pages implementation is in hugetlbpage.c *
+ * *
+ *****************************************************************************/