Linux-RISC-V Archive on lore.kernel.org
 help / color / Atom feed
From: Atish Patra <atish.patra@wdc.com>
To: linux-kernel@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>,
	linux-efi@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
	Kees Cook <keescook@chromium.org>, Nick Hu <nickhu@andestech.com>,
	"Paul E. McKenney" <paulmck@kernel.org>,
	Masahiro Yamada <masahiroy@kernel.org>,
	Anup Patel <anup.patel@wdc.com>, Yash Shah <yash.shah@sifive.com>,
	Ard Biesheuvel <ardb@kernel.org>,
	Atish Patra <atish.patra@wdc.com>,
	Arvind Sankar <nivedita@alum.mit.edu>,
	Palmer Dabbelt <palmer@dabbelt.com>, Zong Li <zong.li@sifive.com>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Greentime Hu <greentime.hu@sifive.com>,
	linux-riscv@lists.infradead.org, Will Deacon <will@kernel.org>,
	Ingo Molnar <mingo@kernel.org>, Mike Rapoport <rppt@kernel.org>
Subject: [RFT PATCH v4 3/9] RISC-V: Implement late mapping page table allocation functions
Date: Wed, 29 Jul 2020 16:36:29 -0700
Message-ID: <20200729233635.14406-4-atish.patra@wdc.com> (raw)
In-Reply-To: <20200729233635.14406-1-atish.patra@wdc.com>

Currently, page table setup is done during setup_va_final where fixmap can
be used to create the temporary mappings. The physical frame is allocated
from memblock_alloc_* functions. However, this won't work if page table
mapping needs to be created for a different mm context (i.e. efi mm) at
a later point of time.

Use generic kernel page allocation function & macros for any mapping
after setup_vm_final.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
---
 arch/riscv/mm/init.c | 29 ++++++++++++++++++++++++-----
 1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 68c608a0e91f..cba03fec08c1 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -212,6 +212,7 @@ pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
 static bool mmu_enabled;
+static bool late_mapping;
 
 #define MAX_EARLY_MAPPING_SIZE	SZ_128M
 
@@ -236,7 +237,9 @@ void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
 
 static pte_t *__init get_pte_virt(phys_addr_t pa)
 {
-	if (mmu_enabled) {
+	if (late_mapping)
+		return (pte_t *) __va(pa);
+	else if (mmu_enabled) {
 		clear_fixmap(FIX_PTE);
 		return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
 	} else {
@@ -246,13 +249,19 @@ static pte_t *__init get_pte_virt(phys_addr_t pa)
 
 static phys_addr_t __init alloc_pte(uintptr_t va)
 {
+	unsigned long vaddr;
 	/*
 	 * We only create PMD or PGD early mappings so we
 	 * should never reach here with MMU disabled.
 	 */
 	BUG_ON(!mmu_enabled);
-
-	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
+	if (late_mapping) {
+		vaddr = __get_free_page(GFP_KERNEL);
+		if (!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)))
+			BUG();
+		return __pa(vaddr);
+	} else
+		return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 }
 
 static void __init create_pte_mapping(pte_t *ptep,
@@ -281,7 +290,9 @@ pmd_t early_pmd[PTRS_PER_PMD * NUM_EARLY_PMDS] __initdata __aligned(PAGE_SIZE);
 
 static pmd_t *__init get_pmd_virt(phys_addr_t pa)
 {
-	if (mmu_enabled) {
+	if (late_mapping)
+		return (pmd_t *) __va(pa);
+	else if (mmu_enabled) {
 		clear_fixmap(FIX_PMD);
 		return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
 	} else {
@@ -292,8 +303,13 @@ static pmd_t *__init get_pmd_virt(phys_addr_t pa)
 static phys_addr_t __init alloc_pmd(uintptr_t va)
 {
 	uintptr_t pmd_num;
+	unsigned long vaddr;
 
-	if (mmu_enabled)
+	if (late_mapping) {
+		vaddr = __get_free_page(GFP_KERNEL);
+		BUG_ON(!vaddr);
+		return __pa(vaddr);
+	} else if (mmu_enabled)
 		return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 
 	pmd_num = (va - PAGE_OFFSET) >> PGDIR_SHIFT;
@@ -533,6 +549,9 @@ static void __init setup_vm_final(void)
 	/* Move to swapper page table */
 	csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
 	local_flush_tlb_all();
+
+	/* generic page allocation function must be used to setup page table */
+	late_mapping = true;
 }
 #else
 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
-- 
2.24.0


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

  parent reply index

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-29 23:36 [RFT PATCH v4 0/9] Add UEFI support for RISC-V Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 1/9] RISC-V: Move DT mapping outof fixmap Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 2/9] RISC-V: Add early ioremap support Atish Patra
2020-07-29 23:36 ` Atish Patra [this message]
2020-07-30  9:14   ` [RFT PATCH v4 3/9] RISC-V: Implement late mapping page table allocation functions Mike Rapoport
2020-08-03  0:55     ` Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 4/9] include: pe.h: Add RISC-V related PE definition Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 5/9] RISC-V: Add PE/COFF header for EFI stub Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 6/9] RISC-V: Add EFI stub support Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 7/9] efi: Rename arm-init to efi-init common for all arch Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 8/9] RISC-V: Add EFI runtime services Atish Patra
2020-07-29 23:36 ` [RFT PATCH v4 9/9] RISC-V: Add page table dump support for uefi Atish Patra
2020-07-31 13:25 ` [RFT PATCH v4 0/9] Add UEFI support for RISC-V Ard Biesheuvel

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=20200729233635.14406-4-atish.patra@wdc.com \
    --to=atish.patra@wdc.com \
    --cc=anup.patel@wdc.com \
    --cc=ardb@kernel.org \
    --cc=greentime.hu@sifive.com \
    --cc=keescook@chromium.org \
    --cc=linux-efi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=mark.rutland@arm.com \
    --cc=masahiroy@kernel.org \
    --cc=mingo@kernel.org \
    --cc=nickhu@andestech.com \
    --cc=nivedita@alum.mit.edu \
    --cc=palmer@dabbelt.com \
    --cc=paul.walmsley@sifive.com \
    --cc=paulmck@kernel.org \
    --cc=rppt@kernel.org \
    --cc=tglx@linutronix.de \
    --cc=will@kernel.org \
    --cc=yash.shah@sifive.com \
    --cc=zong.li@sifive.com \
    /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

Linux-RISC-V Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-riscv/0 linux-riscv/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-riscv linux-riscv/ https://lore.kernel.org/linux-riscv \
		linux-riscv@lists.infradead.org
	public-inbox-index linux-riscv

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-riscv


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git