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powerpc/mm: handle hugepage size correctly when invalidating hpte entries

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If a hash bucket gets full, we "evict" a more/less random entry from it.
When we do that we don't invalidate the TLB (hpte_remove) because we assume
the old translation is still technically "valid". This implies that when
we are invalidating or updating pte, even if HPTE entry is not valid
we should do a tlb invalidate. With hugepages, we need to pass the correct
actual page size value for tlb invalidation.

This change update the patch 0608d69246
"powerpc/mm: Always invalidate tlb on hpte invalidate and update" to handle
transparent hugepages correctly.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Aneesh Kumar K.V
2013-06-20 14:30:13 +05:30
committed by Benjamin Herrenschmidt
parent 8998897b8f
commit db3d853490
9 changed files with 95 additions and 107 deletions
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122
arch/powerpc/mm/hash_native_64.c
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@@ -273,61 +273,15 @@ static long native_hpte_remove(unsigned long hpte_group)
return i;
}
static inline int __hpte_actual_psize(unsigned int lp, int psize)
{
int i, shift;
unsigned int mask;
/* start from 1 ignoring MMU_PAGE_4K */
for (i = 1; i < MMU_PAGE_COUNT; i++) {
/* invalid penc */
if (mmu_psize_defs[psize].penc[i] == -1)
continue;
/*
* encoding bits per actual page size
* PTE LP actual page size
* rrrr rrrz >=8KB
* rrrr rrzz >=16KB
* rrrr rzzz >=32KB
* rrrr zzzz >=64KB
* .......
*/
shift = mmu_psize_defs[i].shift - LP_SHIFT;
if (shift > LP_BITS)
shift = LP_BITS;
mask = (1 << shift) - 1;
if ((lp & mask) == mmu_psize_defs[psize].penc[i])
return i;
}
return -1;
}
static inline int hpte_actual_psize(struct hash_pte *hptep, int psize)
{
/* Look at the 8 bit LP value */
unsigned int lp = (hptep->r >> LP_SHIFT) & ((1 << LP_BITS) - 1);
if (!(hptep->v & HPTE_V_VALID))
return -1;
/* First check if it is large page */
if (!(hptep->v & HPTE_V_LARGE))
return MMU_PAGE_4K;
return __hpte_actual_psize(lp, psize);
}
static long native_hpte_updatepp(unsigned long slot, unsigned long newpp,
unsigned long vpn, int psize, int ssize,
int local)
unsigned long vpn, int bpsize,
int apsize, int ssize, int local)
{
struct hash_pte *hptep = htab_address + slot;
unsigned long hpte_v, want_v;
int ret = 0;
int actual_psize;
want_v = hpte_encode_avpn(vpn, psize, ssize);
want_v = hpte_encode_avpn(vpn, bpsize, ssize);
DBG_LOW(" update(vpn=%016lx, avpnv=%016lx, group=%lx, newpp=%lx)",
vpn, want_v & HPTE_V_AVPN, slot, newpp);
@@ -335,7 +289,6 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp,
native_lock_hpte(hptep);
hpte_v = hptep->v;
actual_psize = hpte_actual_psize(hptep, psize);
/*
* We need to invalidate the TLB always because hpte_remove doesn't do
* a tlb invalidate. If a hash bucket gets full, we "evict" a more/less
@@ -343,12 +296,7 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp,
* (hpte_remove) because we assume the old translation is still
* technically "valid".
*/
if (actual_psize < 0) {
actual_psize = psize;
ret = -1;
goto err_out;
}
if (!HPTE_V_COMPARE(hpte_v, want_v)) {
if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID)) {
DBG_LOW(" -> miss\n");
ret = -1;
} else {
@@ -357,11 +305,10 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp,
hptep->r = (hptep->r & ~(HPTE_R_PP | HPTE_R_N)) |
(newpp & (HPTE_R_PP | HPTE_R_N | HPTE_R_C));
}
err_out:
native_unlock_hpte(hptep);
/* Ensure it is out of the tlb too. */
tlbie(vpn, psize, actual_psize, ssize, local);
tlbie(vpn, bpsize, apsize, ssize, local);
return ret;
}
@@ -402,7 +349,6 @@ static long native_hpte_find(unsigned long vpn, int psize, int ssize)
static void native_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,
int psize, int ssize)
{
int actual_psize;
unsigned long vpn;
unsigned long vsid;
long slot;
@@ -415,36 +361,33 @@ static void native_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,
if (slot == -1)
panic("could not find page to bolt\n");
hptep = htab_address + slot;
actual_psize = hpte_actual_psize(hptep, psize);
if (actual_psize < 0)
actual_psize = psize;
/* Update the HPTE */
hptep->r = (hptep->r & ~(HPTE_R_PP | HPTE_R_N)) |
(newpp & (HPTE_R_PP | HPTE_R_N));
/* Ensure it is out of the tlb too. */
tlbie(vpn, psize, actual_psize, ssize, 0);
/*
* Ensure it is out of the tlb too. Bolted entries base and
* actual page size will be same.
*/
tlbie(vpn, psize, psize, ssize, 0);
}
static void native_hpte_invalidate(unsigned long slot, unsigned long vpn,
int psize, int ssize, int local)
int bpsize, int apsize, int ssize, int local)
{
struct hash_pte *hptep = htab_address + slot;
unsigned long hpte_v;
unsigned long want_v;
unsigned long flags;
int actual_psize;
local_irq_save(flags);
DBG_LOW(" invalidate(vpn=%016lx, hash: %lx)\n", vpn, slot);
want_v = hpte_encode_avpn(vpn, psize, ssize);
want_v = hpte_encode_avpn(vpn, bpsize, ssize);
native_lock_hpte(hptep);
hpte_v = hptep->v;
actual_psize = hpte_actual_psize(hptep, psize);
/*
* We need to invalidate the TLB always because hpte_remove doesn't do
* a tlb invalidate. If a hash bucket gets full, we "evict" a more/less
@@ -452,23 +395,48 @@ static void native_hpte_invalidate(unsigned long slot, unsigned long vpn,
* (hpte_remove) because we assume the old translation is still
* technically "valid".
*/
if (actual_psize < 0) {
actual_psize = psize;
native_unlock_hpte(hptep);
goto err_out;
}
if (!HPTE_V_COMPARE(hpte_v, want_v))
if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID))
native_unlock_hpte(hptep);
else
/* Invalidate the hpte. NOTE: this also unlocks it */
hptep->v = 0;
err_out:
/* Invalidate the TLB */
tlbie(vpn, psize, actual_psize, ssize, local);
tlbie(vpn, bpsize, apsize, ssize, local);
local_irq_restore(flags);
}
static inline int __hpte_actual_psize(unsigned int lp, int psize)
{
int i, shift;
unsigned int mask;
/* start from 1 ignoring MMU_PAGE_4K */
for (i = 1; i < MMU_PAGE_COUNT; i++) {
/* invalid penc */
if (mmu_psize_defs[psize].penc[i] == -1)
continue;
/*
* encoding bits per actual page size
* PTE LP actual page size
* rrrr rrrz >=8KB
* rrrr rrzz >=16KB
* rrrr rzzz >=32KB
* rrrr zzzz >=64KB
* .......
*/
shift = mmu_psize_defs[i].shift - LP_SHIFT;
if (shift > LP_BITS)
shift = LP_BITS;
mask = (1 << shift) - 1;
if ((lp & mask) == mmu_psize_defs[psize].penc[i])
return i;
}
return -1;
}
static void hpte_decode(struct hash_pte *hpte, unsigned long slot,
int *psize, int *apsize, int *ssize, unsigned long *vpn)
{