[PATCHv2 10/10] arm64/head: convert idmap_pg_dir and init_pg_dir to __create_pgd_mapping()
Pingfan Liu
kernelfans at gmail.com
Sun Apr 25 15:13:04 BST 2021
Now, everything is ready for calling __create_pgd_mapping() from head.S.
Switching to these C routine and remove the asm counterpart.
This patch has been successfully tested with the following config value:
PAGE_SIZE VA PA PGTABLE_LEVEL
4K 48 48 4
4K 39 48 3
16K 48 48 4
16K 47 48 3
64K 52 52 3
64K 42 52 2
Signed-off-by: Pingfan Liu <kernelfans at gmail.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will at kernel.org>
Cc: Marc Zyngier <maz at kernel.org>
Cc: Kristina Martsenko <kristina.martsenko at arm.com>
Cc: James Morse <james.morse at arm.com>
Cc: Steven Price <steven.price at arm.com>
Cc: Jonathan Cameron <Jonathan.Cameron at huawei.com>
Cc: Pavel Tatashin <pasha.tatashin at soleen.com>
Cc: Anshuman Khandual <anshuman.khandual at arm.com>
Cc: Atish Patra <atish.patra at wdc.com>
Cc: Mike Rapoport <rppt at kernel.org>
Cc: Logan Gunthorpe <logang at deltatee.com>
Cc: Mark Brown <broonie at kernel.org>
To: linux-arm-kernel at lists.infradead.org
---
RFC -> V2:
correct the asm calling convention.
---
arch/arm64/include/asm/pgalloc.h | 5 +
arch/arm64/kernel/head.S | 193 ++++++++-----------------------
arch/arm64/mm/mmu.c | 13 +++
3 files changed, 66 insertions(+), 145 deletions(-)
diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h
index c3875af99432..b1182b656b00 100644
--- a/arch/arm64/include/asm/pgalloc.h
+++ b/arch/arm64/include/asm/pgalloc.h
@@ -8,6 +8,9 @@
#ifndef __ASM_PGALLOC_H
#define __ASM_PGALLOC_H
+#include <vdso/bits.h>
+
+#ifndef __ASSEMBLY__
#include <asm/pgtable-hwdef.h>
#include <asm/processor.h>
#include <asm/cacheflush.h>
@@ -102,6 +105,8 @@ extern void create_idmap(pgd_t *pgdir, phys_addr_t phys,
void *info,
int flags);
+#endif
+
#define NO_BLOCK_MAPPINGS BIT(0)
#define NO_CONT_MAPPINGS BIT(1)
#define NO_FIXMAP BIT(2)
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index e19649dbbafb..ddb9601d61c2 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -28,6 +28,8 @@
#include <asm/memory.h>
#include <asm/pgtable-hwdef.h>
#include <asm/page.h>
+#include <asm/pgtable-prot.h>
+#include <asm/pgalloc.h>
#include <asm/scs.h>
#include <asm/smp.h>
#include <asm/sysreg.h>
@@ -92,6 +94,8 @@ SYM_CODE_START(primary_entry)
bl init_kernel_el // w0=cpu_boot_mode
adrp x23, __PHYS_OFFSET
and x23, x23, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0
+ adrp x4, init_thread_union
+ add sp, x4, #THREAD_SIZE
bl set_cpu_boot_mode_flag
bl __create_page_tables
/*
@@ -121,135 +125,6 @@ SYM_CODE_START_LOCAL(preserve_boot_args)
b __inval_dcache_area // tail call
SYM_CODE_END(preserve_boot_args)
-/*
- * Macro to create a table entry to the next page.
- *
- * tbl: page table address
- * virt: virtual address
- * shift: #imm page table shift
- * ptrs: #imm pointers per table page
- *
- * Preserves: virt
- * Corrupts: ptrs, tmp1, tmp2
- * Returns: tbl -> next level table page address
- */
- .macro create_table_entry, tbl, virt, shift, ptrs, tmp1, tmp2
- add \tmp1, \tbl, #PAGE_SIZE
- phys_to_pte \tmp2, \tmp1
- orr \tmp2, \tmp2, #PMD_TYPE_TABLE // address of next table and entry type
- lsr \tmp1, \virt, #\shift
- sub \ptrs, \ptrs, #1
- and \tmp1, \tmp1, \ptrs // table index
- str \tmp2, [\tbl, \tmp1, lsl #3]
- add \tbl, \tbl, #PAGE_SIZE // next level table page
- .endm
-
-/*
- * Macro to populate page table entries, these entries can be pointers to the next level
- * or last level entries pointing to physical memory.
- *
- * tbl: page table address
- * rtbl: pointer to page table or physical memory
- * index: start index to write
- * eindex: end index to write - [index, eindex] written to
- * flags: flags for pagetable entry to or in
- * inc: increment to rtbl between each entry
- * tmp1: temporary variable
- *
- * Preserves: tbl, eindex, flags, inc
- * Corrupts: index, tmp1
- * Returns: rtbl
- */
- .macro populate_entries, tbl, rtbl, index, eindex, flags, inc, tmp1
-.Lpe\@: phys_to_pte \tmp1, \rtbl
- orr \tmp1, \tmp1, \flags // tmp1 = table entry
- str \tmp1, [\tbl, \index, lsl #3]
- add \rtbl, \rtbl, \inc // rtbl = pa next level
- add \index, \index, #1
- cmp \index, \eindex
- b.ls .Lpe\@
- .endm
-
-/*
- * Compute indices of table entries from virtual address range. If multiple entries
- * were needed in the previous page table level then the next page table level is assumed
- * to be composed of multiple pages. (This effectively scales the end index).
- *
- * vstart: virtual address of start of range
- * vend: virtual address of end of range
- * shift: shift used to transform virtual address into index
- * ptrs: number of entries in page table
- * istart: index in table corresponding to vstart
- * iend: index in table corresponding to vend
- * count: On entry: how many extra entries were required in previous level, scales
- * our end index.
- * On exit: returns how many extra entries required for next page table level
- *
- * Preserves: vstart, vend, shift, ptrs
- * Returns: istart, iend, count
- */
- .macro compute_indices, vstart, vend, shift, ptrs, istart, iend, count
- lsr \iend, \vend, \shift
- mov \istart, \ptrs
- sub \istart, \istart, #1
- and \iend, \iend, \istart // iend = (vend >> shift) & (ptrs - 1)
- mov \istart, \ptrs
- mul \istart, \istart, \count
- add \iend, \iend, \istart // iend += (count - 1) * ptrs
- // our entries span multiple tables
-
- lsr \istart, \vstart, \shift
- mov \count, \ptrs
- sub \count, \count, #1
- and \istart, \istart, \count
-
- sub \count, \iend, \istart
- .endm
-
-/*
- * Map memory for specified virtual address range. Each level of page table needed supports
- * multiple entries. If a level requires n entries the next page table level is assumed to be
- * formed from n pages.
- *
- * tbl: location of page table
- * rtbl: address to be used for first level page table entry (typically tbl + PAGE_SIZE)
- * vstart: start address to map
- * vend: end address to map - we map [vstart, vend]
- * flags: flags to use to map last level entries
- * phys: physical address corresponding to vstart - physical memory is contiguous
- * pgds: the number of pgd entries
- *
- * Temporaries: istart, iend, tmp, count, sv - these need to be different registers
- * Preserves: vstart, vend, flags
- * Corrupts: tbl, rtbl, istart, iend, tmp, count, sv
- */
- .macro map_memory, tbl, rtbl, vstart, vend, flags, phys, pgds, istart, iend, tmp, count, sv
- add \rtbl, \tbl, #PAGE_SIZE
- mov \sv, \rtbl
- mov \count, #0
- compute_indices \vstart, \vend, #PGDIR_SHIFT, \pgds, \istart, \iend, \count
- populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
- mov \tbl, \sv
- mov \sv, \rtbl
-
-#if SWAPPER_PGTABLE_LEVELS > 3
- compute_indices \vstart, \vend, #PUD_SHIFT, #PTRS_PER_PUD, \istart, \iend, \count
- populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
- mov \tbl, \sv
- mov \sv, \rtbl
-#endif
-
-#if SWAPPER_PGTABLE_LEVELS > 2
- compute_indices \vstart, \vend, #SWAPPER_TABLE_SHIFT, #PTRS_PER_PMD, \istart, \iend, \count
- populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
- mov \tbl, \sv
-#endif
-
- compute_indices \vstart, \vend, #SWAPPER_BLOCK_SHIFT, #PTRS_PER_PTE, \istart, \iend, \count
- bic \count, \phys, #SWAPPER_BLOCK_SIZE - 1
- populate_entries \tbl, \count, \istart, \iend, \flags, #SWAPPER_BLOCK_SIZE, \tmp
- .endm
-
/*
* Setup the initial page tables. We only setup the barest amount which is
* required to get the kernel running. The following sections are required:
@@ -345,8 +220,6 @@ SYM_FUNC_START_LOCAL(__create_page_tables)
mov x5, #1
str x5, [x4] //require expanded pagetable
- mov x4, EXTRA_PTRS
- create_table_entry x0, x3, EXTRA_SHIFT, x4, x5, x6
#else
/*
* If VA_BITS == 48, we don't have to configure an additional
@@ -356,25 +229,55 @@ SYM_FUNC_START_LOCAL(__create_page_tables)
str_l x4, idmap_ptrs_per_pgd, x5
#endif
1:
- ldr_l x4, idmap_ptrs_per_pgd
- mov x5, x3 // __pa(__idmap_text_start)
- adr_l x6, __idmap_text_end // __pa(__idmap_text_end)
-
- map_memory x0, x1, x3, x6, x7, x3, x4, x10, x11, x12, x13, x14
+ stp x0, x1, [sp, #-64]!
+ stp x2, x3, [sp, #48]
+ stp x4, x5, [sp, #32]
+ stp x6, x7, [sp, #16]
+
+ adrp x0, idmap_pg_dir
+ adrp x1, idmap_pg_end
+ sub x1, x1, x0
+ bl set_cur_mempool
+ mov x0, #0
+ mov x0, #0
+ bl head_pgtable_alloc // x0 contains idmap_pg_dir
+
+ adrp x1, __idmap_text_start
+ adr_l x2, __idmap_text_end
+ sub x2, x2, x1
+ ldr x3, =PAGE_KERNEL_EXEC
+ adr_l x4, head_pgtable_alloc
+ mov x5, #0
+ mov x6, #(NO_FIXMAP | BOOT_HEAD)
+ bl create_idmap
/*
* Map the kernel image (starting with PHYS_OFFSET).
*/
adrp x0, init_pg_dir
- mov_q x5, KIMAGE_VADDR // compile time __va(_text)
- add x5, x5, x23 // add KASLR displacement
- mov x4, PTRS_PER_PGD
- adrp x6, _end // runtime __pa(_end)
- adrp x3, _text // runtime __pa(_text)
- sub x6, x6, x3 // _end - _text
- add x6, x6, x5 // runtime __va(_end)
-
- map_memory x0, x1, x5, x6, x7, x3, x4, x10, x11, x12, x13, x14
+ adrp x1, init_pg_end
+ sub x1, x1, x0
+ bl set_cur_mempool
+ mov x0, #0
+ mov x0, #0
+ bl head_pgtable_alloc // x0 is init_pg_dir
+
+ adrp x1, _text // runtime __pa(_text)
+ mov_q x2, KIMAGE_VADDR // compile time __va(_text)
+ add x2, x2, x23 // add KASLR displacement
+ adrp x3, _end // runtime __pa(_end)
+ sub x3, x3, x1 // _end - _text
+
+ ldr x4, =PAGE_KERNEL_EXEC
+ adr_l x5, head_pgtable_alloc
+ mov x6, #0
+ mov x7, #(NO_FIXMAP | BOOT_HEAD)
+
+ bl create_init_pgd_mapping
+ ldp x6, x7, [sp, #16]
+ ldp x4, x5, [sp, #32]
+ ldp x2, x3, [sp, #48]
+ ldp x0, x1, [sp], #64
/*
* Since the page tables have been populated with non-cacheable
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index fa1d1d4fee8f..1ae72a3f2d27 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -167,6 +167,19 @@ static phys_addr_t pgd_pgtable_alloc(unsigned long shift, void *unused)
#include "./mmu_include.c"
+void create_init_pgd_mapping(pgd_t *pgdir,
+ phys_addr_t phys,
+ unsigned long virt,
+ phys_addr_t size,
+ pgprot_t prot,
+ pgtable_alloc allocator,
+ void* info,
+ int flags)
+{
+ __create_pgd_mapping(pgdir, PTRS_PER_PGD, phys, virt, size,
+ prot, allocator, info, flags);
+}
+
int idmap_extend_pgtable;
/*
--
2.29.2
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