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| author |   Christophe Leroy <christophe.leroy@csgroup.eu> | 2020-10-12 08:54:33 +0000 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2020-11-05 23:34:25 +1100 |
| commit | 33fe43cfd9b1c20f6f9899b44bf04e91823ff1c9 (patch) | |
| tree | 7b59cf264092897fcef311841c33540604407040 /arch/powerpc/include/asm/nohash/32/pte-8xx.h | |
| parent | powerpc/8xx: Always fault when _PAGE_ACCESSED is not set (diff) | |
| download | wireguard-linux-33fe43cfd9b1c20f6f9899b44bf04e91823ff1c9.tar.xz wireguard-linux-33fe43cfd9b1c20f6f9899b44bf04e91823ff1c9.zip | |
powerpc/8xx: Manage _PAGE_ACCESSED through APG bits in L1 entry
When _PAGE_ACCESSED is not set, a minor fault is expected.
To do this, TLB miss exception ANDs _PAGE_PRESENT and _PAGE_ACCESSED
into the L2 entry valid bit.
To simplify the processing and reduce the number of instructions in
TLB miss exceptions, manage it as an APG bit and get it next to
_PAGE_GUARDED bit to allow a copy in one go. Then declare the
corresponding groups as handling all accesses as user accesses.
As the PP bits always define user as No Access, it will generate
a fault.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/80f488db230c6b0e7b3b990d72bd94a8a069e93e.1602492856.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/include/asm/nohash/32/pte-8xx.h')
| -rw-r--r-- | arch/powerpc/include/asm/nohash/32/pte-8xx.h | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/arch/powerpc/include/asm/nohash/32/pte-8xx.h b/arch/powerpc/include/asm/nohash/32/pte-8xx.h index 66f403a7da44..1581204467e1 100644 --- a/arch/powerpc/include/asm/nohash/32/pte-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/pte-8xx.h @@ -39,9 +39,9 @@ * into the TLB. */ #define _PAGE_GUARDED 0x0010 /* Copied to L1 G entry in DTLB */ -#define _PAGE_SPECIAL 0x0020 /* SW entry */ +#define _PAGE_ACCESSED 0x0020 /* Copied to L1 APG 1 entry in I/DTLB */ #define _PAGE_EXEC 0x0040 /* Copied to PP (bit 21) in ITLB */ -#define _PAGE_ACCESSED 0x0080 /* software: page referenced */ +#define _PAGE_SPECIAL 0x0080 /* SW entry */ #define _PAGE_NA 0x0200 /* Supervisor NA, User no access */ #define _PAGE_RO 0x0600 /* Supervisor RO, User no access */ @@ -59,11 +59,12 @@ #define _PMD_PRESENT 0x0001 #define _PMD_PRESENT_MASK _PMD_PRESENT -#define _PMD_BAD 0x0fd0 +#define _PMD_BAD 0x0f90 #define _PMD_PAGE_MASK 0x000c #define _PMD_PAGE_8M 0x000c #define _PMD_PAGE_512K 0x0004 -#define _PMD_USER 0x0020 /* APG 1 */ +#define _PMD_ACCESSED 0x0020 /* APG 1 */ +#define _PMD_USER 0x0040 /* APG 2 */ #define _PTE_NONE_MASK 0 |