From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELsnHnMueKeEUYHv87gRHCgzSjG0EBPt1Bt2jeE8sdbeMsk0hOCC6bnkPTMTqIdDIN2xg80+ ARC-Seal: i=1; a=rsa-sha256; t=1521546370; cv=none; d=google.com; s=arc-20160816; b=n+pW8nO/IplTCru4XQFroEtQEc83AIeoiVq5SancAbHRMm+R8gxZRDlXMRnbpuDslr /ydFxIe0P/Lp1hpNRg4ZbPsB2KRdxOsFxbbQT3po9np/ihhCF42DHHDYbo+buGhI40yJ 9X8XotHTaxEpPP5qmXdZn4qTHabgE11mX0gBWo+BsbQt3QeKaQlrp2GoqBPU5oLVHMUF uC9v9T8ejOn4Jcblrpru5mbonn6R/Bciafcyyp4RpDMybVyTpCEeH9xEtWhl7rOLNjaN ANHZKIeTpgCFpoSoD8OZq83RpQqnVnEyTUh+6W3lT1OcEdpoizN5Vjf14w3unhlYQ+Nj CXDg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dmarc-filter:dkim-signature:dkim-signature :arc-authentication-results; bh=82uqdUv7wwFkMPQOFmfwklyNbtxu81+6YtmkTdCB24w=; b=i41OPK+5eNUaPjVZON7y5jwe5dQriKq7VRdHG+4IDgKpbb/wn56yb8HmArgq8RKUIV VLCS+2DnwY5Jx8zBDXyOlBQ7yNT1IoumB4UCeaEvlz0lEOJu2ptBKh3wPpQf1uoRtpeH ZhB0PXxfPLrR5ISN+X9AaTy9OsArPER/hdGfzRSNKAd3/Ilbs/zO9u1C16qPTKrYPKos 5NKJYibZeYubgShob+lIB9lJk97uI8QyP+rBJnxE/2a62MwHvwKJIGffAcYr8lh9gwsZ w/XDRz4j3RsRHh7YdG/Yo2lck3RR4pH2zrX0wRIKh1NeiBcOuNEyn3OuKGjrV91iWfsI Mraw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@codeaurora.org header.s=default header.b=c8XztDlw; dkim=pass header.i=@codeaurora.org header.s=default header.b=myGrS5Rf; spf=pass (google.com: domain of cpandya@codeaurora.org designates 198.145.29.96 as permitted sender) smtp.mailfrom=cpandya@codeaurora.org Authentication-Results: mx.google.com; dkim=pass header.i=@codeaurora.org header.s=default header.b=c8XztDlw; dkim=pass header.i=@codeaurora.org header.s=default header.b=myGrS5Rf; spf=pass (google.com: domain of cpandya@codeaurora.org designates 198.145.29.96 as permitted sender) smtp.mailfrom=cpandya@codeaurora.org DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org DE2BB60F5C Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=cpandya@codeaurora.org From: Chintan Pandya To: catalin.marinas@arm.com, will.deacon@arm.com, mark.rutland@arm.com Cc: arnd@arndb.de, ard.biesheuvel@linaro.org, marc.zyngier@arm.com, james.morse@arm.com, kristina.martsenko@arm.com, takahiro.akashi@linaro.org, gregkh@linuxfoundation.org, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, akpm@linux-foundation.org, toshi.kani@hpe.com, Chintan Pandya Subject: [PATCH v4 2/3] arm64: Implement page table free interfaces Date: Tue, 20 Mar 2018 17:15:13 +0530 Message-Id: <1521546314-31753-3-git-send-email-cpandya@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1521546314-31753-1-git-send-email-cpandya@codeaurora.org> References: <1521546314-31753-1-git-send-email-cpandya@codeaurora.org> X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1595007777008930452?= X-GMAIL-MSGID: =?utf-8?q?1595457006098694593?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Implement pud_free_pmd_page() and pmd_free_pte_page(). Implementation requires, 1) Freeing of the un-used next level page tables 2) Clearing off the current pud/pmd entry 3) Invalidate TLB which could have previously valid but not stale entry Signed-off-by: Chintan Pandya --- arch/arm64/mm/mmu.c | 40 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 38 insertions(+), 2 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index da98828..7be3106 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -45,6 +45,7 @@ #include #include #include +#include #define NO_BLOCK_MAPPINGS BIT(0) #define NO_CONT_MAPPINGS BIT(1) @@ -973,12 +974,47 @@ int pmd_clear_huge(pmd_t *pmdp) return 1; } +static int __pmd_free_pte_page(pmd_t *pmd, unsigned long addr, bool tlb_inv) +{ + pmd_t *table; + + if (pmd_val(*pmd)) { + table = __va(pmd_val(*pmd)); + pmd_clear(pmd); + /* + * FIXME: __flush_tlb_pgtable(&init_mm, addr) is + * ideal candidate here, which exactly + * flushes intermediate pgtables. But, + * this is broken (evident from tests). + * So, use safe TLB op unless that is fixed. + */ + if (tlb_inv) + flush_tlb_kernel_range(addr, addr + PMD_SIZE); + + free_page((unsigned long) table); + } + return 1; +} + int pud_free_pmd_page(pud_t *pud, unsigned long addr) { - return pud_none(*pud); + pmd_t *table; + int i; + + if (pud_val(*pud)) { + table = __va(pud_val(*pud)); + for (i = 0; i < PTRS_PER_PMD; i++) + __pmd_free_pte_page(&table[i], addr + (i * PMD_SIZE), + false); + + pud_clear(pud); + flush_tlb_kernel_range(addr, addr + PUD_SIZE); + free_page((unsigned long) table); + } + return 1; } int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) { - return pmd_none(*pmd); + return __pmd_free_pte_page(pmd, addr, true); } -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project