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kernel-ark/include/asm-parisc/pgtable.h
Kyle McMartin d912e1dc8b [PARISC] move VMALLOC_* definitions to fixmap.h 
They make way more sense here, really...

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:49 -07:00

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#ifndef _PARISC_PGTABLE_H
#define _PARISC_PGTABLE_H
#include <asm-generic/4level-fixup.h>
#include <asm/fixmap.h>
#ifndef __ASSEMBLY__
/*
* we simulate an x86-style page table for the linux mm code
*/
#include <linux/mm.h> /* for vm_area_struct */
#include <linux/bitops.h>
#include <asm/processor.h>
#include <asm/cache.h>
/*
* kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
* memory. For the return value to be meaningful, ADDR must be >=
* PAGE_OFFSET. This operation can be relatively expensive (e.g.,
* require a hash-, or multi-level tree-lookup or something of that
* sort) but it guarantees to return TRUE only if accessing the page
* at that address does not cause an error. Note that there may be
* addresses for which kern_addr_valid() returns FALSE even though an
* access would not cause an error (e.g., this is typically true for
* memory mapped I/O regions.
*
* XXX Need to implement this for parisc.
*/
#define kern_addr_valid(addr) (1)
/* Certain architectures need to do special things when PTEs
* within a page table are directly modified. Thus, the following
* hook is made available.
*/
#define set_pte(pteptr, pteval) \
do{ \
*(pteptr) = (pteval); \
} while(0)
#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
#endif /* !__ASSEMBLY__ */
#define pte_ERROR(e) \
printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
#define pmd_ERROR(e) \
printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
/* This is the size of the initially mapped kernel memory */
#ifdef CONFIG_64BIT
#define KERNEL_INITIAL_ORDER 24 /* 0 to 1<<24 = 16MB */
#else
#define KERNEL_INITIAL_ORDER 23 /* 0 to 1<<23 = 8MB */
#endif
#define KERNEL_INITIAL_SIZE (1 << KERNEL_INITIAL_ORDER)
#if defined(CONFIG_64BIT) && defined(CONFIG_PARISC_PAGE_SIZE_4KB)
#define PT_NLEVELS 3
#define PGD_ORDER 1 /* Number of pages per pgd */
#define PMD_ORDER 1 /* Number of pages per pmd */
#define PGD_ALLOC_ORDER 2 /* first pgd contains pmd */
#else
#define PT_NLEVELS 2
#define PGD_ORDER 1 /* Number of pages per pgd */
#define PGD_ALLOC_ORDER PGD_ORDER
#endif
/* Definitions for 3rd level (we use PLD here for Page Lower directory
* because PTE_SHIFT is used lower down to mean shift that has to be
* done to get usable bits out of the PTE) */
#define PLD_SHIFT PAGE_SHIFT
#define PLD_SIZE PAGE_SIZE
#define BITS_PER_PTE (PAGE_SHIFT - BITS_PER_PTE_ENTRY)
#define PTRS_PER_PTE (1UL << BITS_PER_PTE)
/* Definitions for 2nd level */
#define pgtable_cache_init() do { } while (0)
#define PMD_SHIFT (PLD_SHIFT + BITS_PER_PTE)
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
#if PT_NLEVELS == 3
#define BITS_PER_PMD (PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
#else
#define BITS_PER_PMD 0
#endif
#define PTRS_PER_PMD (1UL << BITS_PER_PMD)
/* Definitions for 1st level */
#define PGDIR_SHIFT (PMD_SHIFT + BITS_PER_PMD)
#define BITS_PER_PGD (PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
#define PTRS_PER_PGD (1UL << BITS_PER_PGD)
#define USER_PTRS_PER_PGD PTRS_PER_PGD
#define MAX_ADDRBITS (PGDIR_SHIFT + BITS_PER_PGD)
#define MAX_ADDRESS (1UL << MAX_ADDRBITS)
#define SPACEID_SHIFT (MAX_ADDRBITS - 32)
/* This calculates the number of initial pages we need for the initial
* page tables */
#if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
# define PT_INITIAL (1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
#else
# define PT_INITIAL (1) /* all initial PTEs fit into one page */
#endif
/*
* pgd entries used up by user/kernel:
*/
#define FIRST_USER_ADDRESS 0
/* NB: The tlb miss handlers make certain assumptions about the order */
/* of the following bits, so be careful (One example, bits 25-31 */
/* are moved together in one instruction). */
#define _PAGE_READ_BIT 31 /* (0x001) read access allowed */
#define _PAGE_WRITE_BIT 30 /* (0x002) write access allowed */
#define _PAGE_EXEC_BIT 29 /* (0x004) execute access allowed */
#define _PAGE_GATEWAY_BIT 28 /* (0x008) privilege promotion allowed */
#define _PAGE_DMB_BIT 27 /* (0x010) Data Memory Break enable (B bit) */
#define _PAGE_DIRTY_BIT 26 /* (0x020) Page Dirty (D bit) */
#define _PAGE_FILE_BIT _PAGE_DIRTY_BIT /* overload this bit */
#define _PAGE_REFTRAP_BIT 25 /* (0x040) Page Ref. Trap enable (T bit) */
#define _PAGE_NO_CACHE_BIT 24 /* (0x080) Uncached Page (U bit) */
#define _PAGE_ACCESSED_BIT 23 /* (0x100) Software: Page Accessed */
#define _PAGE_PRESENT_BIT 22 /* (0x200) Software: translation valid */
#define _PAGE_FLUSH_BIT 21 /* (0x400) Software: translation valid */
/* for cache flushing only */
#define _PAGE_USER_BIT 20 /* (0x800) Software: User accessible page */
/* N.B. The bits are defined in terms of a 32 bit word above, so the */
/* following macro is ok for both 32 and 64 bit. */
#define xlate_pabit(x) (31 - x)
/* this defines the shift to the usable bits in the PTE it is set so
* that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
* to zero */
#define PTE_SHIFT xlate_pabit(_PAGE_USER_BIT)
/* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
#define PFN_PTE_SHIFT 12
/* this is how many bits may be used by the file functions */
#define PTE_FILE_MAX_BITS (BITS_PER_LONG - PTE_SHIFT)
#define pte_to_pgoff(pte) (pte_val(pte) >> PTE_SHIFT)
#define pgoff_to_pte(off) ((pte_t) { ((off) << PTE_SHIFT) | _PAGE_FILE })
#define _PAGE_READ (1 << xlate_pabit(_PAGE_READ_BIT))
#define _PAGE_WRITE (1 << xlate_pabit(_PAGE_WRITE_BIT))
#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE)
#define _PAGE_EXEC (1 << xlate_pabit(_PAGE_EXEC_BIT))
#define _PAGE_GATEWAY (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
#define _PAGE_DMB (1 << xlate_pabit(_PAGE_DMB_BIT))
#define _PAGE_DIRTY (1 << xlate_pabit(_PAGE_DIRTY_BIT))
#define _PAGE_REFTRAP (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
#define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
#define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
#define _PAGE_PRESENT (1 << xlate_pabit(_PAGE_PRESENT_BIT))
#define _PAGE_FLUSH (1 << xlate_pabit(_PAGE_FLUSH_BIT))
#define _PAGE_USER (1 << xlate_pabit(_PAGE_USER_BIT))
#define _PAGE_FILE (1 << xlate_pabit(_PAGE_FILE_BIT))
#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _PAGE_KERNEL (_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
/* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
* are page-aligned, we don't care about the PAGE_OFFSET bits, except
* for a few meta-information bits, so we shift the address to be
* able to effectively address 40/42/44-bits of physical address space
* depending on 4k/16k/64k PAGE_SIZE */
#define _PxD_PRESENT_BIT 31
#define _PxD_ATTACHED_BIT 30
#define _PxD_VALID_BIT 29
#define PxD_FLAG_PRESENT (1 << xlate_pabit(_PxD_PRESENT_BIT))
#define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
#define PxD_FLAG_VALID (1 << xlate_pabit(_PxD_VALID_BIT))
#define PxD_FLAG_MASK (0xf)
#define PxD_FLAG_SHIFT (4)
#define PxD_VALUE_SHIFT (8) /* (PAGE_SHIFT-PxD_FLAG_SHIFT) */
#ifndef __ASSEMBLY__
#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_ACCESSED)
/* Others seem to make this executable, I don't know if that's correct
or not. The stack is mapped this way though so this is necessary
in the short term - dhd@linuxcare.com, 2000-08-08 */
#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_ACCESSED)
#define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE | _PAGE_ACCESSED)
#define PAGE_EXECREAD __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC |_PAGE_ACCESSED)
#define PAGE_COPY PAGE_EXECREAD
#define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC |_PAGE_ACCESSED)
#define PAGE_KERNEL __pgprot(_PAGE_KERNEL)
#define PAGE_KERNEL_RO __pgprot(_PAGE_KERNEL & ~_PAGE_WRITE)
#define PAGE_KERNEL_UNC __pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
#define PAGE_GATEWAY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_GATEWAY| _PAGE_READ)
#define PAGE_FLUSH __pgprot(_PAGE_FLUSH)
/*
* We could have an execute only page using "gateway - promote to priv
* level 3", but that is kind of silly. So, the way things are defined
* now, we must always have read permission for pages with execute
* permission. For the fun of it we'll go ahead and support write only
* pages.
*/
/*xwr*/
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
#define __P010 __P000 /* copy on write */
#define __P011 __P001 /* copy on write */
#define __P100 PAGE_EXECREAD
#define __P101 PAGE_EXECREAD
#define __P110 __P100 /* copy on write */
#define __P111 __P101 /* copy on write */
#define __S000 PAGE_NONE
#define __S001 PAGE_READONLY
#define __S010 PAGE_WRITEONLY
#define __S011 PAGE_SHARED
#define __S100 PAGE_EXECREAD
#define __S101 PAGE_EXECREAD
#define __S110 PAGE_RWX
#define __S111 PAGE_RWX
extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
/* initial page tables for 0-8MB for kernel */
extern pte_t pg0[];
/* zero page used for uninitialized stuff */
extern unsigned long *empty_zero_page;
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
#define pte_none(x) ((pte_val(x) == 0) || (pte_val(x) & _PAGE_FLUSH))
#define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
#define pte_clear(mm,addr,xp) do { pte_val(*(xp)) = 0; } while (0)
#define pmd_flag(x) (pmd_val(x) & PxD_FLAG_MASK)
#define pmd_address(x) ((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
#define pgd_flag(x) (pgd_val(x) & PxD_FLAG_MASK)
#define pgd_address(x) ((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
#if PT_NLEVELS == 3
/* The first entry of the permanent pmd is not there if it contains
* the gateway marker */
#define pmd_none(x) (!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
#else
#define pmd_none(x) (!pmd_val(x))
#endif
#define pmd_bad(x) (!(pmd_flag(x) & PxD_FLAG_VALID))
#define pmd_present(x) (pmd_flag(x) & PxD_FLAG_PRESENT)
static inline void pmd_clear(pmd_t *pmd) {
#if PT_NLEVELS == 3
if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
/* This is the entry pointing to the permanent pmd
* attached to the pgd; cannot clear it */
__pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
else
#endif
__pmd_val_set(*pmd, 0);
}
#if PT_NLEVELS == 3
#define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
#define pgd_page(pgd) virt_to_page((void *)pgd_page_vaddr(pgd))
/* For 64 bit we have three level tables */
#define pgd_none(x) (!pgd_val(x))
#define pgd_bad(x) (!(pgd_flag(x) & PxD_FLAG_VALID))
#define pgd_present(x) (pgd_flag(x) & PxD_FLAG_PRESENT)
static inline void pgd_clear(pgd_t *pgd) {
#if PT_NLEVELS == 3
if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
/* This is the permanent pmd attached to the pgd; cannot
* free it */
return;
#endif
__pgd_val_set(*pgd, 0);
}
#else
/*
* The "pgd_xxx()" functions here are trivial for a folded two-level
* setup: the pgd is never bad, and a pmd always exists (as it's folded
* into the pgd entry)
*/
static inline int pgd_none(pgd_t pgd) { return 0; }
static inline int pgd_bad(pgd_t pgd) { return 0; }
static inline int pgd_present(pgd_t pgd) { return 1; }
static inline void pgd_clear(pgd_t * pgdp) { }
#endif
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
*/
static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }
static inline pte_t pte_mkclean(pte_t pte) { pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
static inline pte_t pte_mkold(pte_t pte) { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
static inline pte_t pte_wrprotect(pte_t pte) { pte_val(pte) &= ~_PAGE_WRITE; return pte; }
static inline pte_t pte_mkdirty(pte_t pte) { pte_val(pte) |= _PAGE_DIRTY; return pte; }
static inline pte_t pte_mkyoung(pte_t pte) { pte_val(pte) |= _PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkwrite(pte_t pte) { pte_val(pte) |= _PAGE_WRITE; return pte; }
/*
* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.
*/
#define __mk_pte(addr,pgprot) \
({ \
pte_t __pte; \
\
pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot)); \
\
__pte; \
})
#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
{
pte_t pte;
pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
return pte;
}
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
/* Permanent address of a page. On parisc we don't have highmem. */
#define pte_pfn(x) (pte_val(x) >> PFN_PTE_SHIFT)
#define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_address(pmd)))
#define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
#define pmd_page(pmd) virt_to_page((void *)__pmd_page(pmd))
#define pgd_index(address) ((address) >> PGDIR_SHIFT)
/* to find an entry in a page-table-directory */
#define pgd_offset(mm, address) \
((mm)->pgd + ((address) >> PGDIR_SHIFT))
/* to find an entry in a kernel page-table-directory */
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
/* Find an entry in the second-level page table.. */
#if PT_NLEVELS == 3
#define pmd_offset(dir,address) \
((pmd_t *) pgd_page_vaddr(*(dir)) + (((address)>>PMD_SHIFT) & (PTRS_PER_PMD-1)))
#else
#define pmd_offset(dir,addr) ((pmd_t *) dir)
#endif
/* Find an entry in the third-level page table.. */
#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
#define pte_offset_kernel(pmd, address) \
((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
#define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
#define pte_offset_map_nested(pmd, address) pte_offset_kernel(pmd, address)
#define pte_unmap(pte) do { } while (0)
#define pte_unmap_nested(pte) do { } while (0)
#define pte_unmap(pte) do { } while (0)
#define pte_unmap_nested(pte) do { } while (0)
extern void paging_init (void);
/* Used for deferring calls to flush_dcache_page() */
#define PG_dcache_dirty PG_arch_1
extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t);
/* Encode and de-code a swap entry */
#define __swp_type(x) ((x).val & 0x1f)
#define __swp_offset(x) ( (((x).val >> 6) & 0x7) | \
(((x).val >> 8) & ~0x7) )
#define __swp_entry(type, offset) ((swp_entry_t) { (type) | \
((offset & 0x7) << 6) | \
((offset & ~0x7) << 8) })
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
{
#ifdef CONFIG_SMP
if (!pte_young(*ptep))
return 0;
return test_and_clear_bit(xlate_pabit(_PAGE_ACCESSED_BIT), &pte_val(*ptep));
#else
pte_t pte = *ptep;
if (!pte_young(pte))
return 0;
set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
return 1;
#endif
}
extern spinlock_t pa_dbit_lock;
struct mm_struct;
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pte_t old_pte;
pte_t pte;
spin_lock(&pa_dbit_lock);
pte = old_pte = *ptep;
pte_val(pte) &= ~_PAGE_PRESENT;
pte_val(pte) |= _PAGE_FLUSH;
set_pte_at(mm,addr,ptep,pte);
spin_unlock(&pa_dbit_lock);
return old_pte;
}
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
#ifdef CONFIG_SMP
unsigned long new, old;
do {
old = pte_val(*ptep);
new = pte_val(pte_wrprotect(__pte (old)));
} while (cmpxchg((unsigned long *) ptep, old, new) != old);
#else
pte_t old_pte = *ptep;
set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
#endif
}
#define pte_same(A,B) (pte_val(A) == pte_val(B))
#endif /* !__ASSEMBLY__ */
/* TLB page size encoding - see table 3-1 in parisc20.pdf */
#define _PAGE_SIZE_ENCODING_4K 0
#define _PAGE_SIZE_ENCODING_16K 1
#define _PAGE_SIZE_ENCODING_64K 2
#define _PAGE_SIZE_ENCODING_256K 3
#define _PAGE_SIZE_ENCODING_1M 4
#define _PAGE_SIZE_ENCODING_4M 5
#define _PAGE_SIZE_ENCODING_16M 6
#define _PAGE_SIZE_ENCODING_64M 7
#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
#elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
#elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
#endif
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)
#define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
/* We provide our own get_unmapped_area to provide cache coherency */
#define HAVE_ARCH_UNMAPPED_AREA
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
#define __HAVE_ARCH_PTE_SAME
#include <asm-generic/pgtable.h>
#endif /* _PARISC_PGTABLE_H */
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