From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx190.postini.com [74.125.245.190]) by kanga.kvack.org (Postfix) with SMTP id 1914E6B000E for ; Tue, 26 Feb 2013 03:05:55 -0500 (EST) Received: from /spool/local by e23smtp08.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 26 Feb 2013 18:04:04 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 18F372BB0051 for ; Tue, 26 Feb 2013 19:05:52 +1100 (EST) Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r1Q85n757143852 for ; Tue, 26 Feb 2013 19:05:49 +1100 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r1Q85phf008279 for ; Tue, 26 Feb 2013 19:05:51 +1100 From: "Aneesh Kumar K.V" Subject: [PATCH -V1 14/24] powerpc: Fix hpte_decode to use the correct decoding for page sizes Date: Tue, 26 Feb 2013 13:35:04 +0530 Message-Id: <1361865914-13911-15-git-send-email-aneesh.kumar@linux.vnet.ibm.com> In-Reply-To: <1361865914-13911-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> References: <1361865914-13911-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: benh@kernel.crashing.org, paulus@samba.org Cc: linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, "Aneesh Kumar K.V" From: "Aneesh Kumar K.V" As per ISA doc, we encode base and actual page size in the LP bits of PTE. The number of bit used to encode the page sizes depend on actual page size. ISA doc lists this as PTE LP actual page size rrrr rrrz a?JPY8KB rrrr rrzz a?JPY16KB rrrr rzzz a?JPY32KB rrrr zzzz a?JPY64KB rrrz zzzz a?JPY128KB rrzz zzzz a?JPY256KB rzzz zzzz a?JPY512KB zzzz zzzz a?JPY1MB ISA doc also says "The values of the a??za?? bits used to specify each size, along with all possible values of a??ra?? bits in the LP field, must result in LP values distinct from other LP values for other sizes." based on the above update hpte_decode to use the correct decoding for LP bits. Signed-off-by: Aneesh Kumar K.V --- arch/powerpc/mm/hash_native_64.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c index e800b26..2c6940f 100644 --- a/arch/powerpc/mm/hash_native_64.c +++ b/arch/powerpc/mm/hash_native_64.c @@ -428,19 +428,15 @@ static void hpte_decode(struct hash_pte *hpte, unsigned long slot, int *psize, int *apsize, int *ssize, unsigned long *vpn) { unsigned long avpn, pteg, vpi; - unsigned long hpte_r = hpte->r; unsigned long hpte_v = hpte->v; unsigned long vsid, seg_off; - int i, size, a_size = MMU_PAGE_4K, shift, penc; + int size, a_size = MMU_PAGE_4K, shift, mask; + /* Look at the 8 bit LP value */ + unsigned int lp = (hpte->r >> LP_SHIFT) & ((1 << LP_BITS) - 1); if (!(hpte_v & HPTE_V_LARGE)) size = MMU_PAGE_4K; else { - for (i = 0; i < LP_BITS; i++) { - if ((hpte_r & LP_MASK(i+1)) == LP_MASK(i+1)) - break; - } - penc = LP_MASK(i+1) >> LP_SHIFT; for (size = 0; size < MMU_PAGE_COUNT; size++) { /* 4K pages are not represented by LP */ @@ -450,12 +446,23 @@ static void hpte_decode(struct hash_pte *hpte, unsigned long slot, /* valid entries have a shift value */ if (!mmu_psize_defs[size].shift) continue; - for (a_size = 0; a_size < MMU_PAGE_COUNT; a_size++) - if (penc == mmu_psize_defs[size].penc[a_size]) + + for (a_size = 0; a_size < MMU_PAGE_COUNT; a_size++) { + /* valid entries have a shift value */ + if (!mmu_psize_defs[a_size].shift) + continue; + + shift = mmu_psize_defs[a_size].shift - 11; + if (shift > 9) + shift = 9; + mask = (1 << shift) - 1; + if ((lp & mask) == + mmu_psize_defs[size].penc[a_size]) { goto out; + } + } } } - out: /* This works for all page sizes, and for 256M and 1T segments */ *ssize = hpte_v >> HPTE_V_SSIZE_SHIFT; -- 1.7.10 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org