From: Nikos Nikoleris <nikos.nikoleris@arm.com>
To: kvm@vger.kernel.org
Cc: mark.rutland@arm.com, jade.alglave@arm.com,
luc.maranget@inria.fr, andre.przywara@arm.com,
alexandru.elisei@arm.com, Luc Maranget <Luc.Maranget@inria.fr>
Subject: [kvm-unit-tests PATCH 1/2] arm: Add mmu_get_pte() to the MMU API
Date: Mon, 2 Nov 2020 11:53:10 +0000 [thread overview]
Message-ID: <20201102115311.103750-2-nikos.nikoleris@arm.com> (raw)
In-Reply-To: <20201102115311.103750-1-nikos.nikoleris@arm.com>
From: Luc Maranget <Luc.Maranget@inria.fr>
Add the mmu_get_pte() function that allows a test to get a pointer to
the PTE for a valid virtual address. Return NULL if the MMU is off.
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
---
lib/arm/asm/mmu-api.h | 1 +
lib/arm/mmu.c | 23 ++++++++++++++---------
2 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/lib/arm/asm/mmu-api.h b/lib/arm/asm/mmu-api.h
index 2bbe1fa..3d04d03 100644
--- a/lib/arm/asm/mmu-api.h
+++ b/lib/arm/asm/mmu-api.h
@@ -22,5 +22,6 @@ extern void mmu_set_range_sect(pgd_t *pgtable, uintptr_t virt_offset,
extern void mmu_set_range_ptes(pgd_t *pgtable, uintptr_t virt_offset,
phys_addr_t phys_start, phys_addr_t phys_end,
pgprot_t prot);
+extern pteval_t *mmu_get_pte(pgd_t *pgtable, uintptr_t vaddr);
extern void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr);
#endif
diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c
index 51fa745..2113604 100644
--- a/lib/arm/mmu.c
+++ b/lib/arm/mmu.c
@@ -210,7 +210,7 @@ unsigned long __phys_to_virt(phys_addr_t addr)
return addr;
}
-void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr)
+pteval_t *mmu_get_pte(pgd_t *pgtable, uintptr_t vaddr)
{
pgd_t *pgd;
pud_t *pud;
@@ -218,7 +218,7 @@ void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr)
pte_t *pte;
if (!mmu_enabled())
- return;
+ return NULL;
pgd = pgd_offset(pgtable, vaddr);
assert(pgd_valid(*pgd));
@@ -228,16 +228,21 @@ void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr)
assert(pmd_valid(*pmd));
if (pmd_huge(*pmd)) {
- pmd_t entry = __pmd(pmd_val(*pmd) & ~PMD_SECT_USER);
- WRITE_ONCE(*pmd, entry);
- goto out_flush_tlb;
+ return &pmd_val(*pmd);
}
pte = pte_offset(pmd, vaddr);
assert(pte_valid(*pte));
- pte_t entry = __pte(pte_val(*pte) & ~PTE_USER);
- WRITE_ONCE(*pte, entry);
-out_flush_tlb:
- flush_tlb_page(vaddr);
+ return &pte_val(*pte);
+}
+
+void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr)
+{
+ pteval_t *p_pte = mmu_get_pte(pgtable, vaddr);
+ if (p_pte) {
+ pteval_t entry = *p_pte & ~PTE_USER;
+ WRITE_ONCE(*p_pte, entry);
+ flush_tlb_page(vaddr);
+ }
}
--
2.17.1
next prev parent reply other threads:[~2020-11-02 11:53 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-02 11:53 [kvm-unit-tests PATCH 0/2] arm: MMU extentions to enable litmus7 Nikos Nikoleris
2020-11-02 11:53 ` Nikos Nikoleris [this message]
2020-11-03 17:10 ` [kvm-unit-tests PATCH 1/2] arm: Add mmu_get_pte() to the MMU API Andrew Jones
2020-11-05 14:27 ` Alexandru Elisei
2020-11-07 11:01 ` Nikos Nikoleris
2020-11-09 12:36 ` Alexandru Elisei
2020-11-09 12:49 ` Andrew Jones
2020-11-02 11:53 ` [kvm-unit-tests PATCH 2/2] arm: Add support for the DEVICE_nGRE and NORMAL_WT memory types Nikos Nikoleris
2020-11-03 17:10 ` Andrew Jones
2020-11-03 17:09 ` [kvm-unit-tests PATCH 0/2] arm: MMU extentions to enable litmus7 Andrew Jones
2020-11-03 17:17 ` Nikos Nikoleris
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