From: Steve Capper <steve.capper@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: crecklin@redhat.com, ard.biesheuvel@linaro.org,
catalin.marinas@arm.com, bhsharma@redhat.com,
Steve Capper <steve.capper@arm.com>,
maz@kernel.org, will@kernel.org
Subject: [PATCH V4 06/11] arm64: mm: Introduce VA_BITS_ACTUAL
Date: Mon, 29 Jul 2019 17:21:12 +0100 [thread overview]
Message-ID: <20190729162117.832-7-steve.capper@arm.com> (raw)
In-Reply-To: <20190729162117.832-1-steve.capper@arm.com>
In order to support 52-bit kernel addresses detectable at boot time, one
needs to know the actual VA_BITS detected. A new variable VA_BITS_ACTUAL
is introduced in this commit and employed for the KVM hypervisor layout,
KASAN, fault handling and phys-to/from-virt translation where there
would normally be compile time constants.
In order to maintain performance in phys_to_virt, another variable
physvirt_offset is introduced.
Signed-off-by: Steve Capper <steve.capper@arm.com>
---
arch/arm64/include/asm/kasan.h | 2 +-
arch/arm64/include/asm/memory.h | 12 +++++++-----
arch/arm64/include/asm/mmu_context.h | 2 +-
arch/arm64/kernel/head.S | 5 +++++
arch/arm64/kvm/va_layout.c | 14 +++++++-------
arch/arm64/mm/fault.c | 4 ++--
arch/arm64/mm/init.c | 7 ++++++-
arch/arm64/mm/mmu.c | 3 +++
8 files changed, 32 insertions(+), 17 deletions(-)
diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h
index 10d2add842da..ff991dc86ae1 100644
--- a/arch/arm64/include/asm/kasan.h
+++ b/arch/arm64/include/asm/kasan.h
@@ -31,7 +31,7 @@
* (1ULL << (64 - KASAN_SHADOW_SCALE_SHIFT))
*/
#define _KASAN_SHADOW_START(va) (KASAN_SHADOW_END - (1UL << ((va) - KASAN_SHADOW_SCALE_SHIFT)))
-#define KASAN_SHADOW_START _KASAN_SHADOW_START(VA_BITS)
+#define KASAN_SHADOW_START _KASAN_SHADOW_START(VA_BITS_ACTUAL)
void kasan_init(void);
void kasan_copy_shadow(pgd_t *pgdir);
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index a8a91a573bff..93341f4fe840 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -37,8 +37,6 @@
* VA_START - the first kernel virtual address.
*/
#define VA_BITS (CONFIG_ARM64_VA_BITS)
-#define VA_START (UL(0xffffffffffffffff) - \
- (UL(1) << (VA_BITS - 1)) + 1)
#define PAGE_OFFSET (UL(0xffffffffffffffff) - \
(UL(1) << VA_BITS) + 1)
#define KIMAGE_VADDR (MODULES_END)
@@ -166,10 +164,14 @@
#endif
#ifndef __ASSEMBLY__
+extern u64 vabits_actual;
+#define VA_BITS_ACTUAL ({vabits_actual;})
+#define VA_START (_VA_START(VA_BITS_ACTUAL))
#include <linux/bitops.h>
#include <linux/mmdebug.h>
+extern s64 physvirt_offset;
extern s64 memstart_addr;
/* PHYS_OFFSET - the physical address of the start of memory. */
#define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
@@ -236,9 +238,9 @@ extern u64 vabits_user;
* space. Testing the top bit for the start of the region is a
* sufficient check.
*/
-#define __is_lm_address(addr) (!((addr) & BIT(VA_BITS - 1)))
+#define __is_lm_address(addr) (!((addr) & BIT(VA_BITS_ACTUAL - 1)))
-#define __lm_to_phys(addr) (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
+#define __lm_to_phys(addr) (((addr) + physvirt_offset))
#define __kimg_to_phys(addr) ((addr) - kimage_voffset)
#define __virt_to_phys_nodebug(x) ({ \
@@ -257,7 +259,7 @@ extern phys_addr_t __phys_addr_symbol(unsigned long x);
#define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
#endif
-#define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
+#define __phys_to_virt(x) ((unsigned long)((x) - physvirt_offset))
#define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset))
/*
diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h
index 7ed0adb187a8..890ccaf02264 100644
--- a/arch/arm64/include/asm/mmu_context.h
+++ b/arch/arm64/include/asm/mmu_context.h
@@ -95,7 +95,7 @@ static inline void __cpu_set_tcr_t0sz(unsigned long t0sz)
isb();
}
-#define cpu_set_default_tcr_t0sz() __cpu_set_tcr_t0sz(TCR_T0SZ(VA_BITS))
+#define cpu_set_default_tcr_t0sz() __cpu_set_tcr_t0sz(TCR_T0SZ(VA_BITS_ACTUAL))
#define cpu_set_idmap_tcr_t0sz() __cpu_set_tcr_t0sz(idmap_t0sz)
/*
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index ac58c69993ec..6dc7349868d9 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -321,6 +321,11 @@ __create_page_tables:
dmb sy
dc ivac, x6 // Invalidate potentially stale cache line
+ adr_l x6, vabits_actual
+ str x5, [x6]
+ dmb sy
+ dc ivac, x6 // Invalidate potentially stale cache line
+
/*
* VA_BITS may be too small to allow for an ID mapping to be created
* that covers system RAM if that is located sufficiently high in the
diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c
index acd8084f1f2c..aaf1a3d43959 100644
--- a/arch/arm64/kvm/va_layout.c
+++ b/arch/arm64/kvm/va_layout.c
@@ -29,25 +29,25 @@ static void compute_layout(void)
int kva_msb;
/* Where is my RAM region? */
- hyp_va_msb = idmap_addr & BIT(VA_BITS - 1);
- hyp_va_msb ^= BIT(VA_BITS - 1);
+ hyp_va_msb = idmap_addr & BIT(VA_BITS_ACTUAL - 1);
+ hyp_va_msb ^= BIT(VA_BITS_ACTUAL - 1);
kva_msb = fls64((u64)phys_to_virt(memblock_start_of_DRAM()) ^
(u64)(high_memory - 1));
- if (kva_msb == (VA_BITS - 1)) {
+ if (kva_msb == (VA_BITS_ACTUAL - 1)) {
/*
* No space in the address, let's compute the mask so
- * that it covers (VA_BITS - 1) bits, and the region
+ * that it covers (VA_BITS_ACTUAL - 1) bits, and the region
* bit. The tag stays set to zero.
*/
- va_mask = BIT(VA_BITS - 1) - 1;
+ va_mask = BIT(VA_BITS_ACTUAL - 1) - 1;
va_mask |= hyp_va_msb;
} else {
/*
* We do have some free bits to insert a random tag.
* Hyp VAs are now created from kernel linear map VAs
- * using the following formula (with V == VA_BITS):
+ * using the following formula (with V == VA_BITS_ACTUAL):
*
* 63 ... V | V-1 | V-2 .. tag_lsb | tag_lsb - 1 .. 0
* ---------------------------------------------------------
@@ -55,7 +55,7 @@ static void compute_layout(void)
*/
tag_lsb = kva_msb;
va_mask = GENMASK_ULL(tag_lsb - 1, 0);
- tag_val = get_random_long() & GENMASK_ULL(VA_BITS - 2, tag_lsb);
+ tag_val = get_random_long() & GENMASK_ULL(VA_BITS_ACTUAL - 2, tag_lsb);
tag_val |= hyp_va_msb;
tag_val >>= tag_lsb;
}
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 9568c116ac7f..751617613f0c 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -138,9 +138,9 @@ static void show_pte(unsigned long addr)
return;
}
- pr_alert("%s pgtable: %luk pages, %u-bit VAs, pgdp=%016lx\n",
+ pr_alert("%s pgtable: %luk pages, %llu-bit VAs, pgdp=%016lx\n",
mm == &init_mm ? "swapper" : "user", PAGE_SIZE / SZ_1K,
- mm == &init_mm ? VA_BITS : (int)vabits_user,
+ mm == &init_mm ? VA_BITS_ACTUAL : (int)vabits_user,
(unsigned long)virt_to_phys(mm->pgd));
pgdp = pgd_offset(mm, addr);
pgd = READ_ONCE(*pgdp);
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 62927ed02229..189177672567 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -50,6 +50,9 @@
s64 memstart_addr __ro_after_init = -1;
EXPORT_SYMBOL(memstart_addr);
+s64 physvirt_offset __ro_after_init;
+EXPORT_SYMBOL(physvirt_offset);
+
phys_addr_t arm64_dma_phys_limit __ro_after_init;
#ifdef CONFIG_KEXEC_CORE
@@ -301,7 +304,7 @@ static void __init fdt_enforce_memory_region(void)
void __init arm64_memblock_init(void)
{
- const s64 linear_region_size = BIT(VA_BITS - 1);
+ const s64 linear_region_size = BIT(VA_BITS_ACTUAL - 1);
/* Handle linux,usable-memory-range property */
fdt_enforce_memory_region();
@@ -315,6 +318,8 @@ void __init arm64_memblock_init(void)
memstart_addr = round_down(memblock_start_of_DRAM(),
ARM64_MEMSTART_ALIGN);
+ physvirt_offset = PHYS_OFFSET - PAGE_OFFSET;
+
/*
* Remove the memory that we will not be able to cover with the
* linear mapping. Take care not to clip the kernel which may be
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 1d4247f9a496..07b30e6d17f8 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -43,6 +43,9 @@ u64 idmap_ptrs_per_pgd = PTRS_PER_PGD;
u64 vabits_user __ro_after_init;
EXPORT_SYMBOL(vabits_user);
+u64 __section(".mmuoff.data.write") vabits_actual;
+EXPORT_SYMBOL(vabits_actual);
+
u64 kimage_voffset __ro_after_init;
EXPORT_SYMBOL(kimage_voffset);
--
2.20.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-07-29 16:24 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-29 16:21 [PATCH V4 00/11] 52-bit kernel + user VAs Steve Capper
2019-07-29 16:21 ` [PATCH V4 01/11] arm64: mm: Remove bit-masking optimisations for PAGE_OFFSET and VMEMMAP_START Steve Capper
2019-08-05 11:07 ` Catalin Marinas
2019-07-29 16:21 ` [PATCH V4 02/11] arm64: mm: Flip kernel VA space Steve Capper
2019-08-05 11:29 ` Catalin Marinas
2019-08-05 11:50 ` Steve Capper
2019-07-29 16:21 ` [PATCH V4 03/11] arm64: kasan: Switch to using KASAN_SHADOW_OFFSET Steve Capper
2019-08-05 16:37 ` Catalin Marinas
2019-08-06 9:05 ` Steve Capper
2019-07-29 16:21 ` [PATCH V4 04/11] arm64: dump: De-constify VA_START and KASAN_SHADOW_START Steve Capper
2019-08-05 16:38 ` Catalin Marinas
2019-07-29 16:21 ` [PATCH V4 05/11] arm64: mm: Introduce VA_BITS_MIN Steve Capper
2019-08-05 17:17 ` Catalin Marinas
2019-08-05 17:20 ` Catalin Marinas
2019-08-06 9:11 ` Steve Capper
2019-07-29 16:21 ` Steve Capper [this message]
2019-08-05 17:26 ` [PATCH V4 06/11] arm64: mm: Introduce VA_BITS_ACTUAL Catalin Marinas
2019-08-06 11:32 ` Steve Capper
2019-08-06 14:48 ` Catalin Marinas
2019-08-07 13:27 ` Steve Capper
2019-07-29 16:21 ` [PATCH V4 07/11] arm64: mm: Logic to make offset_ttbr1 conditional Steve Capper
2019-08-05 17:06 ` Catalin Marinas
2019-07-29 16:21 ` [PATCH V4 08/11] arm64: mm: Separate out vmemmap Steve Capper
2019-08-05 17:07 ` Catalin Marinas
2019-07-29 16:21 ` [PATCH V4 09/11] arm64: mm: Modify calculation of VMEMMAP_SIZE Steve Capper
2019-08-05 17:10 ` Catalin Marinas
2019-07-29 16:21 ` [PATCH V4 10/11] arm64: mm: Introduce 52-bit Kernel VAs Steve Capper
2019-08-05 17:27 ` Catalin Marinas
2019-08-06 14:55 ` Catalin Marinas
2019-08-06 14:58 ` Catalin Marinas
2019-07-29 16:21 ` [PATCH V4 11/11] docs: arm64: Add layout and 52-bit info to memory document Steve Capper
2019-08-06 15:27 ` Catalin Marinas
2019-08-07 13:29 ` Steve Capper
2019-08-07 14:55 ` Will Deacon
2019-08-07 15:57 ` Steve Capper
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190729162117.832-7-steve.capper@arm.com \
--to=steve.capper@arm.com \
--cc=ard.biesheuvel@linaro.org \
--cc=bhsharma@redhat.com \
--cc=catalin.marinas@arm.com \
--cc=crecklin@redhat.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=maz@kernel.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.