arch/powerpc/include/asm/nohash/32/pgtable.h - third_party/linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _ASM_POWERPC_NOHASH_32_PGTABLE_H
 #define _ASM_POWERPC_NOHASH_32_PGTABLE_H

 #include <asm-generic/pgtable-nopmd.h>

 #ifndef __ASSEMBLY__
 #include <linux/sched.h>
 #include <linux/threads.h>
 #include <asm/mmu.h>			/* For sub-arch specific PPC_PIN_SIZE */

 #endif /* __ASSEMBLY__ */

 #define PTE_INDEX_SIZE	PTE_SHIFT
 #define PMD_INDEX_SIZE	0
 #define PUD_INDEX_SIZE	0
 #define PGD_INDEX_SIZE	(32 - PGDIR_SHIFT)

 #define PMD_CACHE_INDEX	PMD_INDEX_SIZE
 #define PUD_CACHE_INDEX	PUD_INDEX_SIZE

 #ifndef __ASSEMBLY__
 #define PTE_TABLE_SIZE	(sizeof(pte_t) << PTE_INDEX_SIZE)
 #define PMD_TABLE_SIZE	0
 #define PUD_TABLE_SIZE	0
 #define PGD_TABLE_SIZE	(sizeof(pgd_t) << PGD_INDEX_SIZE)

 #define PMD_MASKED_BITS (PTE_TABLE_SIZE - 1)
 #endif	/* __ASSEMBLY__ */

 #define PTRS_PER_PTE	(1 << PTE_INDEX_SIZE)
 #define PTRS_PER_PGD	(1 << PGD_INDEX_SIZE)

 /*
  * The normal case is that PTEs are 32-bits and we have a 1-page
  * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages.  -- paulus
  *
  * For any >32-bit physical address platform, we can use the following
  * two level page table layout where the pgdir is 8KB and the MS 13 bits
  * are an index to the second level table.  The combined pgdir/pmd first
  * level has 2048 entries and the second level has 512 64-bit PTE entries.
  * -Matt
  */
 /* PGDIR_SHIFT determines what a top-level page table entry can map */
 #define PGDIR_SHIFT	(PAGE_SHIFT + PTE_INDEX_SIZE)
 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
 #define PGDIR_MASK	(~(PGDIR_SIZE-1))

 /* Bits to mask out from a PGD to get to the PUD page */
 #define PGD_MASKED_BITS		0

 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)

 #define pgd_ERROR(e) \
 	pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))

 /*
  * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
  * value (for now) on others, from where we can start layout kernel
  * virtual space that goes below PKMAP and FIXMAP
  */

 #define FIXADDR_SIZE	0
 #ifdef CONFIG_KASAN
 #include <asm/kasan.h>
 #define FIXADDR_TOP	(KASAN_SHADOW_START - PAGE_SIZE)
 #else
 #define FIXADDR_TOP	((unsigned long)(-PAGE_SIZE))
 #endif

 /*
  * ioremap_bot starts at that address. Early ioremaps move down from there,
  * until mem_init() at which point this becomes the top of the vmalloc
  * and ioremap space
  */
 #ifdef CONFIG_HIGHMEM
 #define IOREMAP_TOP	PKMAP_BASE
 #else
 #define IOREMAP_TOP	FIXADDR_START
 #endif

 /* PPC32 shares vmalloc area with ioremap */
 #define IOREMAP_START	VMALLOC_START
 #define IOREMAP_END	VMALLOC_END

 /*
  * Just any arbitrary offset to the start of the vmalloc VM area: the
  * current 16MB value just means that there will be a 64MB "hole" after the
  * physical memory until the kernel virtual memory starts.  That means that
  * any out-of-bounds memory accesses will hopefully be caught.
  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
  * area for the same reason. ;)
  *
  * We no longer map larger than phys RAM with the BATs so we don't have
  * to worry about the VMALLOC_OFFSET causing problems.  We do have to worry
  * about clashes between our early calls to ioremap() that start growing down
  * from IOREMAP_TOP being run into the VM area allocations (growing upwards
  * from VMALLOC_START).  For this reason we have ioremap_bot to check when
  * we actually run into our mappings setup in the early boot with the VM
  * system.  This really does become a problem for machines with good amounts
  * of RAM.  -- Cort
  */
 #define VMALLOC_OFFSET (0x1000000) /* 16M */
 #ifdef PPC_PIN_SIZE
 #define VMALLOC_START (((ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
 #else
 #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
 #endif

 #ifdef CONFIG_KASAN_VMALLOC
 #define VMALLOC_END	ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
 #else
 #define VMALLOC_END	ioremap_bot
 #endif

 /*
  * Bits in a linux-style PTE.  These match the bits in the
  * (hardware-defined) PowerPC PTE as closely as possible.
  */

 #if defined(CONFIG_40x)
 #include <asm/nohash/32/pte-40x.h>
 #elif defined(CONFIG_44x)
 #include <asm/nohash/32/pte-44x.h>
 #elif defined(CONFIG_PPC_85xx) && defined(CONFIG_PTE_64BIT)
 #include <asm/nohash/pte-e500.h>
 #elif defined(CONFIG_PPC_85xx)
 #include <asm/nohash/32/pte-85xx.h>
 #elif defined(CONFIG_PPC_8xx)
 #include <asm/nohash/32/pte-8xx.h>
 #endif

 /*
  * Location of the PFN in the PTE. Most 32-bit platforms use the same
  * as _PAGE_SHIFT here (ie, naturally aligned).
  * Platform who don't just pre-define the value so we don't override it here.
  */
 #ifndef PTE_RPN_SHIFT
 #define PTE_RPN_SHIFT	(PAGE_SHIFT)
 #endif

 /*
  * The mask covered by the RPN must be a ULL on 32-bit platforms with
  * 64-bit PTEs.
  */
 #ifdef CONFIG_PTE_64BIT
 #define PTE_RPN_MASK	(~((1ULL << PTE_RPN_SHIFT) - 1))
 #define MAX_POSSIBLE_PHYSMEM_BITS 36
 #else
 #define PTE_RPN_MASK	(~((1UL << PTE_RPN_SHIFT) - 1))
 #define MAX_POSSIBLE_PHYSMEM_BITS 32
 #endif

 #ifndef __ASSEMBLY__

 #define pmd_none(pmd)		(!pmd_val(pmd))
 #define	pmd_bad(pmd)		(pmd_val(pmd) & _PMD_BAD)
 #define	pmd_present(pmd)	(pmd_val(pmd) & _PMD_PRESENT_MASK)
 static inline void pmd_clear(pmd_t *pmdp)
 {
 	*pmdp = __pmd(0);
 }

 /*
  * Note that on Book E processors, the pmd contains the kernel virtual
  * (lowmem) address of the pte page.  The physical address is less useful
  * because everything runs with translation enabled (even the TLB miss
  * handler).  On everything else the pmd contains the physical address
  * of the pte page.  -- paulus
  */
 #ifndef CONFIG_BOOKE
 #define pmd_pfn(pmd)		(pmd_val(pmd) >> PAGE_SHIFT)
 #else
 #define pmd_page_vaddr(pmd)	\
 	((const void *)(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
 #define pmd_pfn(pmd)		(__pa(pmd_val(pmd)) >> PAGE_SHIFT)
 #endif

 #define pmd_page(pmd)		pfn_to_page(pmd_pfn(pmd))

 /*
  * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
  * are !pte_none() && !pte_present().
  *
  * Format of swap PTEs (32bit PTEs):
  *
  *                         1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
  *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  *   <------------------ offset -------------------> < type -> E 0 0
  *
  * E is the exclusive marker that is not stored in swap entries.
  *
  * For 64bit PTEs, the offset is extended by 32bit.
  */
 #define __swp_type(entry)		((entry).val & 0x1f)
 #define __swp_offset(entry)		((entry).val >> 5)
 #define __swp_entry(type, offset)	((swp_entry_t) { ((type) & 0x1f) | ((offset) << 5) })
 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) >> 3 })
 #define __swp_entry_to_pte(x)		((pte_t) { (x).val << 3 })

 /* We borrow LSB 2 to store the exclusive marker in swap PTEs. */
 #define _PAGE_SWP_EXCLUSIVE	0x000004

 #endif /* !__ASSEMBLY__ */

 #endif /* __ASM_POWERPC_NOHASH_32_PGTABLE_H */
	/* SPDX-License-Identifier: GPL-2.0 */
	#ifndef _ASM_POWERPC_NOHASH_32_PGTABLE_H
	#define _ASM_POWERPC_NOHASH_32_PGTABLE_H

	#include <asm-generic/pgtable-nopmd.h>

	#ifndef __ASSEMBLY__
	#include <linux/sched.h>
	#include <linux/threads.h>
	#include <asm/mmu.h> /* For sub-arch specific PPC_PIN_SIZE */

	#endif /* __ASSEMBLY__ */

	#define PTE_INDEX_SIZE PTE_SHIFT
	#define PMD_INDEX_SIZE 0
	#define PUD_INDEX_SIZE 0
	#define PGD_INDEX_SIZE (32 - PGDIR_SHIFT)

	#define PMD_CACHE_INDEX PMD_INDEX_SIZE
	#define PUD_CACHE_INDEX PUD_INDEX_SIZE

	#ifndef __ASSEMBLY__
	#define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_INDEX_SIZE)
	#define PMD_TABLE_SIZE 0
	#define PUD_TABLE_SIZE 0
	#define PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)

	#define PMD_MASKED_BITS (PTE_TABLE_SIZE - 1)
	#endif /* __ASSEMBLY__ */

	#define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
	#define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)

	/*
	* The normal case is that PTEs are 32-bits and we have a 1-page
	* 1024-entry pgdir pointing to 1-page 1024-entry PTE pages. -- paulus
	*
	* For any >32-bit physical address platform, we can use the following
	* two level page table layout where the pgdir is 8KB and the MS 13 bits
	* are an index to the second level table. The combined pgdir/pmd first
	* level has 2048 entries and the second level has 512 64-bit PTE entries.
	* -Matt
	*/
	/* PGDIR_SHIFT determines what a top-level page table entry can map */
	#define PGDIR_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
	#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
	#define PGDIR_MASK (~(PGDIR_SIZE-1))

	/* Bits to mask out from a PGD to get to the PUD page */
	#define PGD_MASKED_BITS 0

	#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)

	#define pgd_ERROR(e) \
	pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))

	/*
	* This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
	* value (for now) on others, from where we can start layout kernel
	* virtual space that goes below PKMAP and FIXMAP
	*/

	#define FIXADDR_SIZE 0
	#ifdef CONFIG_KASAN
	#include <asm/kasan.h>
	#define FIXADDR_TOP (KASAN_SHADOW_START - PAGE_SIZE)
	#else
	#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
	#endif

	/*
	* ioremap_bot starts at that address. Early ioremaps move down from there,
	* until mem_init() at which point this becomes the top of the vmalloc
	* and ioremap space
	*/
	#ifdef CONFIG_HIGHMEM
	#define IOREMAP_TOP PKMAP_BASE
	#else
	#define IOREMAP_TOP FIXADDR_START
	#endif

	/* PPC32 shares vmalloc area with ioremap */
	#define IOREMAP_START VMALLOC_START
	#define IOREMAP_END VMALLOC_END

	/*
	* Just any arbitrary offset to the start of the vmalloc VM area: the
	* current 16MB value just means that there will be a 64MB "hole" after the
	* physical memory until the kernel virtual memory starts. That means that
	* any out-of-bounds memory accesses will hopefully be caught.
	* The vmalloc() routines leaves a hole of 4kB between each vmalloced
	* area for the same reason. ;)
	*
	* We no longer map larger than phys RAM with the BATs so we don't have
	* to worry about the VMALLOC_OFFSET causing problems. We do have to worry
	* about clashes between our early calls to ioremap() that start growing down
	* from IOREMAP_TOP being run into the VM area allocations (growing upwards
	* from VMALLOC_START). For this reason we have ioremap_bot to check when
	* we actually run into our mappings setup in the early boot with the VM
	* system. This really does become a problem for machines with good amounts
	* of RAM. -- Cort
	*/
	#define VMALLOC_OFFSET (0x1000000) /* 16M */
	#ifdef PPC_PIN_SIZE
	#define VMALLOC_START (((ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
	#else
	#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
	#endif

	#ifdef CONFIG_KASAN_VMALLOC
	#define VMALLOC_END ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
	#else
	#define VMALLOC_END ioremap_bot
	#endif

	/*
	* Bits in a linux-style PTE. These match the bits in the
	* (hardware-defined) PowerPC PTE as closely as possible.
	*/

	#if defined(CONFIG_40x)
	#include <asm/nohash/32/pte-40x.h>
	#elif defined(CONFIG_44x)
	#include <asm/nohash/32/pte-44x.h>
	#elif defined(CONFIG_PPC_85xx) && defined(CONFIG_PTE_64BIT)
	#include <asm/nohash/pte-e500.h>
	#elif defined(CONFIG_PPC_85xx)
	#include <asm/nohash/32/pte-85xx.h>
	#elif defined(CONFIG_PPC_8xx)
	#include <asm/nohash/32/pte-8xx.h>
	#endif

	/*
	* Location of the PFN in the PTE. Most 32-bit platforms use the same
	* as _PAGE_SHIFT here (ie, naturally aligned).
	* Platform who don't just pre-define the value so we don't override it here.
	*/
	#ifndef PTE_RPN_SHIFT
	#define PTE_RPN_SHIFT (PAGE_SHIFT)
	#endif

	/*
	* The mask covered by the RPN must be a ULL on 32-bit platforms with
	* 64-bit PTEs.
	*/
	#ifdef CONFIG_PTE_64BIT
	#define PTE_RPN_MASK (~((1ULL << PTE_RPN_SHIFT) - 1))
	#define MAX_POSSIBLE_PHYSMEM_BITS 36
	#else
	#define PTE_RPN_MASK (~((1UL << PTE_RPN_SHIFT) - 1))
	#define MAX_POSSIBLE_PHYSMEM_BITS 32
	#endif

	#ifndef __ASSEMBLY__

	#define pmd_none(pmd) (!pmd_val(pmd))
	#define pmd_bad(pmd) (pmd_val(pmd) & _PMD_BAD)
	#define pmd_present(pmd) (pmd_val(pmd) & _PMD_PRESENT_MASK)
	static inline void pmd_clear(pmd_t *pmdp)
	{
	*pmdp = __pmd(0);
	}

	/*
	* Note that on Book E processors, the pmd contains the kernel virtual
	* (lowmem) address of the pte page. The physical address is less useful
	* because everything runs with translation enabled (even the TLB miss
	* handler). On everything else the pmd contains the physical address
	* of the pte page. -- paulus
	*/
	#ifndef CONFIG_BOOKE
	#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
	#else
	#define pmd_page_vaddr(pmd) \
	((const void *)(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
	#define pmd_pfn(pmd) (__pa(pmd_val(pmd)) >> PAGE_SHIFT)
	#endif

	#define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))

	/*
	* Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
	* are !pte_none() && !pte_present().
	*
	* Format of swap PTEs (32bit PTEs):
	*
	* 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	* <------------------ offset -------------------> < type -> E 0 0
	*
	* E is the exclusive marker that is not stored in swap entries.
	*
	* For 64bit PTEs, the offset is extended by 32bit.
	*/
	#define __swp_type(entry) ((entry).val & 0x1f)
	#define __swp_offset(entry) ((entry).val >> 5)
	#define __swp_entry(type, offset) ((swp_entry_t) { ((type) & 0x1f) \| ((offset) << 5) })
	#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 3 })
	#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 3 })

	/* We borrow LSB 2 to store the exclusive marker in swap PTEs. */
	#define _PAGE_SWP_EXCLUSIVE 0x000004

	#endif /* !__ASSEMBLY__ */

	#endif /* __ASM_POWERPC_NOHASH_32_PGTABLE_H */