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							- /*
 
-  *  arch/arm/include/asm/tlbflush.h
 
-  *
 
-  *  Copyright (C) 1999-2003 Russell King
 
-  *
 
-  * This program is free software; you can redistribute it and/or modify
 
-  * it under the terms of the GNU General Public License version 2 as
 
-  * published by the Free Software Foundation.
 
-  */
 
- #ifndef _ASMARM_TLBFLUSH_H
 
- #define _ASMARM_TLBFLUSH_H
 
- #ifdef CONFIG_MMU
 
- #include <asm/glue.h>
 
- #define TLB_V3_PAGE	(1 << 0)
 
- #define TLB_V4_U_PAGE	(1 << 1)
 
- #define TLB_V4_D_PAGE	(1 << 2)
 
- #define TLB_V4_I_PAGE	(1 << 3)
 
- #define TLB_V6_U_PAGE	(1 << 4)
 
- #define TLB_V6_D_PAGE	(1 << 5)
 
- #define TLB_V6_I_PAGE	(1 << 6)
 
- #define TLB_V3_FULL	(1 << 8)
 
- #define TLB_V4_U_FULL	(1 << 9)
 
- #define TLB_V4_D_FULL	(1 << 10)
 
- #define TLB_V4_I_FULL	(1 << 11)
 
- #define TLB_V6_U_FULL	(1 << 12)
 
- #define TLB_V6_D_FULL	(1 << 13)
 
- #define TLB_V6_I_FULL	(1 << 14)
 
- #define TLB_V6_U_ASID	(1 << 16)
 
- #define TLB_V6_D_ASID	(1 << 17)
 
- #define TLB_V6_I_ASID	(1 << 18)
 
- /* Unified Inner Shareable TLB operations (ARMv7 MP extensions) */
 
- #define TLB_V7_UIS_PAGE	(1 << 19)
 
- #define TLB_V7_UIS_FULL (1 << 20)
 
- #define TLB_V7_UIS_ASID (1 << 21)
 
- #define TLB_BARRIER	(1 << 28)
 
- #define TLB_L2CLEAN_FR	(1 << 29)		/* Feroceon */
 
- #define TLB_DCLEAN	(1 << 30)
 
- #define TLB_WB		(1 << 31)
 
- /*
 
-  *	MMU TLB Model
 
-  *	=============
 
-  *
 
-  *	We have the following to choose from:
 
-  *	  v3    - ARMv3
 
-  *	  v4    - ARMv4 without write buffer
 
-  *	  v4wb  - ARMv4 with write buffer without I TLB flush entry instruction
 
-  *	  v4wbi - ARMv4 with write buffer with I TLB flush entry instruction
 
-  *	  fr    - Feroceon (v4wbi with non-outer-cacheable page table walks)
 
-  *	  fa    - Faraday (v4 with write buffer with UTLB)
 
-  *	  v6wbi - ARMv6 with write buffer with I TLB flush entry instruction
 
-  *	  v7wbi - identical to v6wbi
 
-  */
 
- #undef _TLB
 
- #undef MULTI_TLB
 
- #ifdef CONFIG_SMP_ON_UP
 
- #define MULTI_TLB 1
 
- #endif
 
- #define v4_tlb_flags	(TLB_V4_U_FULL | TLB_V4_U_PAGE)
 
- #ifdef CONFIG_CPU_TLB_V4WT
 
- # define v4_possible_flags	v4_tlb_flags
 
- # define v4_always_flags	v4_tlb_flags
 
- # ifdef _TLB
 
- #  define MULTI_TLB 1
 
- # else
 
- #  define _TLB v4
 
- # endif
 
- #else
 
- # define v4_possible_flags	0
 
- # define v4_always_flags	(-1UL)
 
- #endif
 
- #define fa_tlb_flags	(TLB_WB | TLB_DCLEAN | TLB_BARRIER | \
 
- 			 TLB_V4_U_FULL | TLB_V4_U_PAGE)
 
- #ifdef CONFIG_CPU_TLB_FA
 
- # define fa_possible_flags	fa_tlb_flags
 
- # define fa_always_flags	fa_tlb_flags
 
- # ifdef _TLB
 
- #  define MULTI_TLB 1
 
- # else
 
- #  define _TLB fa
 
- # endif
 
- #else
 
- # define fa_possible_flags	0
 
- # define fa_always_flags	(-1UL)
 
- #endif
 
- #define v4wbi_tlb_flags	(TLB_WB | TLB_DCLEAN | \
 
- 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
 
- 			 TLB_V4_I_PAGE | TLB_V4_D_PAGE)
 
- #ifdef CONFIG_CPU_TLB_V4WBI
 
- # define v4wbi_possible_flags	v4wbi_tlb_flags
 
- # define v4wbi_always_flags	v4wbi_tlb_flags
 
- # ifdef _TLB
 
- #  define MULTI_TLB 1
 
- # else
 
- #  define _TLB v4wbi
 
- # endif
 
- #else
 
- # define v4wbi_possible_flags	0
 
- # define v4wbi_always_flags	(-1UL)
 
- #endif
 
- #define fr_tlb_flags	(TLB_WB | TLB_DCLEAN | TLB_L2CLEAN_FR | \
 
- 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
 
- 			 TLB_V4_I_PAGE | TLB_V4_D_PAGE)
 
- #ifdef CONFIG_CPU_TLB_FEROCEON
 
- # define fr_possible_flags	fr_tlb_flags
 
- # define fr_always_flags	fr_tlb_flags
 
- # ifdef _TLB
 
- #  define MULTI_TLB 1
 
- # else
 
- #  define _TLB v4wbi
 
- # endif
 
- #else
 
- # define fr_possible_flags	0
 
- # define fr_always_flags	(-1UL)
 
- #endif
 
- #define v4wb_tlb_flags	(TLB_WB | TLB_DCLEAN | \
 
- 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
 
- 			 TLB_V4_D_PAGE)
 
- #ifdef CONFIG_CPU_TLB_V4WB
 
- # define v4wb_possible_flags	v4wb_tlb_flags
 
- # define v4wb_always_flags	v4wb_tlb_flags
 
- # ifdef _TLB
 
- #  define MULTI_TLB 1
 
- # else
 
- #  define _TLB v4wb
 
- # endif
 
- #else
 
- # define v4wb_possible_flags	0
 
- # define v4wb_always_flags	(-1UL)
 
- #endif
 
- #define v6wbi_tlb_flags (TLB_WB | TLB_DCLEAN | TLB_BARRIER | \
 
- 			 TLB_V6_I_FULL | TLB_V6_D_FULL | \
 
- 			 TLB_V6_I_PAGE | TLB_V6_D_PAGE | \
 
- 			 TLB_V6_I_ASID | TLB_V6_D_ASID)
 
- #ifdef CONFIG_CPU_TLB_V6
 
- # define v6wbi_possible_flags	v6wbi_tlb_flags
 
- # define v6wbi_always_flags	v6wbi_tlb_flags
 
- # ifdef _TLB
 
- #  define MULTI_TLB 1
 
- # else
 
- #  define _TLB v6wbi
 
- # endif
 
- #else
 
- # define v6wbi_possible_flags	0
 
- # define v6wbi_always_flags	(-1UL)
 
- #endif
 
- #define v7wbi_tlb_flags_smp	(TLB_WB | TLB_DCLEAN | TLB_BARRIER | \
 
- 			 TLB_V7_UIS_FULL | TLB_V7_UIS_PAGE | TLB_V7_UIS_ASID)
 
- #define v7wbi_tlb_flags_up	(TLB_WB | TLB_DCLEAN | TLB_BARRIER | \
 
- 			 TLB_V6_U_FULL | TLB_V6_U_PAGE | TLB_V6_U_ASID)
 
- #ifdef CONFIG_CPU_TLB_V7
 
- # ifdef CONFIG_SMP_ON_UP
 
- #  define v7wbi_possible_flags	(v7wbi_tlb_flags_smp | v7wbi_tlb_flags_up)
 
- #  define v7wbi_always_flags	(v7wbi_tlb_flags_smp & v7wbi_tlb_flags_up)
 
- # elif defined(CONFIG_SMP)
 
- #  define v7wbi_possible_flags	v7wbi_tlb_flags_smp
 
- #  define v7wbi_always_flags	v7wbi_tlb_flags_smp
 
- # else
 
- #  define v7wbi_possible_flags	v7wbi_tlb_flags_up
 
- #  define v7wbi_always_flags	v7wbi_tlb_flags_up
 
- # endif
 
- # ifdef _TLB
 
- #  define MULTI_TLB 1
 
- # else
 
- #  define _TLB v7wbi
 
- # endif
 
- #else
 
- # define v7wbi_possible_flags	0
 
- # define v7wbi_always_flags	(-1UL)
 
- #endif
 
- #ifndef _TLB
 
- #error Unknown TLB model
 
- #endif
 
- #ifndef __ASSEMBLY__
 
- #include <linux/sched.h>
 
- struct cpu_tlb_fns {
 
- 	void (*flush_user_range)(unsigned long, unsigned long, struct vm_area_struct *);
 
- 	void (*flush_kern_range)(unsigned long, unsigned long);
 
- 	unsigned long tlb_flags;
 
- };
 
- /*
 
-  * Select the calling method
 
-  */
 
- #ifdef MULTI_TLB
 
- #define __cpu_flush_user_tlb_range	cpu_tlb.flush_user_range
 
- #define __cpu_flush_kern_tlb_range	cpu_tlb.flush_kern_range
 
- #else
 
- #define __cpu_flush_user_tlb_range	__glue(_TLB,_flush_user_tlb_range)
 
- #define __cpu_flush_kern_tlb_range	__glue(_TLB,_flush_kern_tlb_range)
 
- extern void __cpu_flush_user_tlb_range(unsigned long, unsigned long, struct vm_area_struct *);
 
- extern void __cpu_flush_kern_tlb_range(unsigned long, unsigned long);
 
- #endif
 
- extern struct cpu_tlb_fns cpu_tlb;
 
- #define __cpu_tlb_flags			cpu_tlb.tlb_flags
 
- /*
 
-  *	TLB Management
 
-  *	==============
 
-  *
 
-  *	The arch/arm/mm/tlb-*.S files implement these methods.
 
-  *
 
-  *	The TLB specific code is expected to perform whatever tests it
 
-  *	needs to determine if it should invalidate the TLB for each
 
-  *	call.  Start addresses are inclusive and end addresses are
 
-  *	exclusive; it is safe to round these addresses down.
 
-  *
 
-  *	flush_tlb_all()
 
-  *
 
-  *		Invalidate the entire TLB.
 
-  *
 
-  *	flush_tlb_mm(mm)
 
-  *
 
-  *		Invalidate all TLB entries in a particular address
 
-  *		space.
 
-  *		- mm	- mm_struct describing address space
 
-  *
 
-  *	flush_tlb_range(mm,start,end)
 
-  *
 
-  *		Invalidate a range of TLB entries in the specified
 
-  *		address space.
 
-  *		- mm	- mm_struct describing address space
 
-  *		- start - start address (may not be aligned)
 
-  *		- end	- end address (exclusive, may not be aligned)
 
-  *
 
-  *	flush_tlb_page(vaddr,vma)
 
-  *
 
-  *		Invalidate the specified page in the specified address range.
 
-  *		- vaddr - virtual address (may not be aligned)
 
-  *		- vma	- vma_struct describing address range
 
-  *
 
-  *	flush_kern_tlb_page(kaddr)
 
-  *
 
-  *		Invalidate the TLB entry for the specified page.  The address
 
-  *		will be in the kernels virtual memory space.  Current uses
 
-  *		only require the D-TLB to be invalidated.
 
-  *		- kaddr - Kernel virtual memory address
 
-  */
 
- /*
 
-  * We optimise the code below by:
 
-  *  - building a set of TLB flags that might be set in __cpu_tlb_flags
 
-  *  - building a set of TLB flags that will always be set in __cpu_tlb_flags
 
-  *  - if we're going to need __cpu_tlb_flags, access it once and only once
 
-  *
 
-  * This allows us to build optimal assembly for the single-CPU type case,
 
-  * and as close to optimal given the compiler constrants for multi-CPU
 
-  * case.  We could do better for the multi-CPU case if the compiler
 
-  * implemented the "%?" method, but this has been discontinued due to too
 
-  * many people getting it wrong.
 
-  */
 
- #define possible_tlb_flags	(v4_possible_flags | \
 
- 				 v4wbi_possible_flags | \
 
- 				 fr_possible_flags | \
 
- 				 v4wb_possible_flags | \
 
- 				 fa_possible_flags | \
 
- 				 v6wbi_possible_flags | \
 
- 				 v7wbi_possible_flags)
 
- #define always_tlb_flags	(v4_always_flags & \
 
- 				 v4wbi_always_flags & \
 
- 				 fr_always_flags & \
 
- 				 v4wb_always_flags & \
 
- 				 fa_always_flags & \
 
- 				 v6wbi_always_flags & \
 
- 				 v7wbi_always_flags)
 
- #define tlb_flag(f)	((always_tlb_flags & (f)) || (__tlb_flag & possible_tlb_flags & (f)))
 
- #define __tlb_op(f, insnarg, arg)					\
 
- 	do {								\
 
- 		if (always_tlb_flags & (f))				\
 
- 			asm("mcr " insnarg				\
 
- 			    : : "r" (arg) : "cc");			\
 
- 		else if (possible_tlb_flags & (f))			\
 
- 			asm("tst %1, %2\n\t"				\
 
- 			    "mcrne " insnarg				\
 
- 			    : : "r" (arg), "r" (__tlb_flag), "Ir" (f)	\
 
- 			    : "cc");					\
 
- 	} while (0)
 
- #define tlb_op(f, regs, arg)	__tlb_op(f, "p15, 0, %0, " regs, arg)
 
- #define tlb_l2_op(f, regs, arg)	__tlb_op(f, "p15, 1, %0, " regs, arg)
 
- static inline void local_flush_tlb_all(void)
 
- {
 
- 	const int zero = 0;
 
- 	const unsigned int __tlb_flag = __cpu_tlb_flags;
 
- 	if (tlb_flag(TLB_WB))
 
- 		dsb();
 
- 	tlb_op(TLB_V3_FULL, "c6, c0, 0", zero);
 
- 	tlb_op(TLB_V4_U_FULL | TLB_V6_U_FULL, "c8, c7, 0", zero);
 
- 	tlb_op(TLB_V4_D_FULL | TLB_V6_D_FULL, "c8, c6, 0", zero);
 
- 	tlb_op(TLB_V4_I_FULL | TLB_V6_I_FULL, "c8, c5, 0", zero);
 
- 	tlb_op(TLB_V7_UIS_FULL, "c8, c3, 0", zero);
 
- 	if (tlb_flag(TLB_BARRIER)) {
 
- 		dsb();
 
- 		isb();
 
- 	}
 
- }
 
- static inline void local_flush_tlb_mm(struct mm_struct *mm)
 
- {
 
- 	const int zero = 0;
 
- 	const int asid = ASID(mm);
 
- 	const unsigned int __tlb_flag = __cpu_tlb_flags;
 
- 	if (tlb_flag(TLB_WB))
 
- 		dsb();
 
- 	if (possible_tlb_flags & (TLB_V3_FULL|TLB_V4_U_FULL|TLB_V4_D_FULL|TLB_V4_I_FULL)) {
 
- 		if (cpumask_test_cpu(get_cpu(), mm_cpumask(mm))) {
 
- 			tlb_op(TLB_V3_FULL, "c6, c0, 0", zero);
 
- 			tlb_op(TLB_V4_U_FULL, "c8, c7, 0", zero);
 
- 			tlb_op(TLB_V4_D_FULL, "c8, c6, 0", zero);
 
- 			tlb_op(TLB_V4_I_FULL, "c8, c5, 0", zero);
 
- 		}
 
- 		put_cpu();
 
- 	}
 
- 	tlb_op(TLB_V6_U_ASID, "c8, c7, 2", asid);
 
- 	tlb_op(TLB_V6_D_ASID, "c8, c6, 2", asid);
 
- 	tlb_op(TLB_V6_I_ASID, "c8, c5, 2", asid);
 
- #ifdef CONFIG_ARM_ERRATA_720789
 
- 	tlb_op(TLB_V7_UIS_ASID, "c8, c3, 0", zero);
 
- #else
 
- 	tlb_op(TLB_V7_UIS_ASID, "c8, c3, 2", asid);
 
- #endif
 
- 	if (tlb_flag(TLB_BARRIER))
 
- 		dsb();
 
- }
 
- static inline void
 
- local_flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
 
- {
 
- 	const int zero = 0;
 
- 	const unsigned int __tlb_flag = __cpu_tlb_flags;
 
- 	uaddr = (uaddr & PAGE_MASK) | ASID(vma->vm_mm);
 
- 	if (tlb_flag(TLB_WB))
 
- 		dsb();
 
- 	if (possible_tlb_flags & (TLB_V3_PAGE|TLB_V4_U_PAGE|TLB_V4_D_PAGE|TLB_V4_I_PAGE|TLB_V4_I_FULL) &&
 
- 	    cpumask_test_cpu(smp_processor_id(), mm_cpumask(vma->vm_mm))) {
 
- 		tlb_op(TLB_V3_PAGE, "c6, c0, 0", uaddr);
 
- 		tlb_op(TLB_V4_U_PAGE, "c8, c7, 1", uaddr);
 
- 		tlb_op(TLB_V4_D_PAGE, "c8, c6, 1", uaddr);
 
- 		tlb_op(TLB_V4_I_PAGE, "c8, c5, 1", uaddr);
 
- 		if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
 
- 			asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
 
- 	}
 
- 	tlb_op(TLB_V6_U_PAGE, "c8, c7, 1", uaddr);
 
- 	tlb_op(TLB_V6_D_PAGE, "c8, c6, 1", uaddr);
 
- 	tlb_op(TLB_V6_I_PAGE, "c8, c5, 1", uaddr);
 
- #ifdef CONFIG_ARM_ERRATA_720789
 
- 	tlb_op(TLB_V7_UIS_PAGE, "c8, c3, 3", uaddr & PAGE_MASK);
 
- #else
 
- 	tlb_op(TLB_V7_UIS_PAGE, "c8, c3, 1", uaddr);
 
- #endif
 
- 	if (tlb_flag(TLB_BARRIER))
 
- 		dsb();
 
- }
 
- static inline void local_flush_tlb_kernel_page(unsigned long kaddr)
 
- {
 
- 	const int zero = 0;
 
- 	const unsigned int __tlb_flag = __cpu_tlb_flags;
 
- 	kaddr &= PAGE_MASK;
 
- 	if (tlb_flag(TLB_WB))
 
- 		dsb();
 
- 	tlb_op(TLB_V3_PAGE, "c6, c0, 0", kaddr);
 
- 	tlb_op(TLB_V4_U_PAGE, "c8, c7, 1", kaddr);
 
- 	tlb_op(TLB_V4_D_PAGE, "c8, c6, 1", kaddr);
 
- 	tlb_op(TLB_V4_I_PAGE, "c8, c5, 1", kaddr);
 
- 	if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
 
- 		asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
 
- 	tlb_op(TLB_V6_U_PAGE, "c8, c7, 1", kaddr);
 
- 	tlb_op(TLB_V6_D_PAGE, "c8, c6, 1", kaddr);
 
- 	tlb_op(TLB_V6_I_PAGE, "c8, c5, 1", kaddr);
 
- 	tlb_op(TLB_V7_UIS_PAGE, "c8, c3, 1", kaddr);
 
- 	if (tlb_flag(TLB_BARRIER)) {
 
- 		dsb();
 
- 		isb();
 
- 	}
 
- }
 
- /*
 
-  *	flush_pmd_entry
 
-  *
 
-  *	Flush a PMD entry (word aligned, or double-word aligned) to
 
-  *	RAM if the TLB for the CPU we are running on requires this.
 
-  *	This is typically used when we are creating PMD entries.
 
-  *
 
-  *	clean_pmd_entry
 
-  *
 
-  *	Clean (but don't drain the write buffer) if the CPU requires
 
-  *	these operations.  This is typically used when we are removing
 
-  *	PMD entries.
 
-  */
 
- static inline void flush_pmd_entry(void *pmd)
 
- {
 
- 	const unsigned int __tlb_flag = __cpu_tlb_flags;
 
- 	tlb_op(TLB_DCLEAN, "c7, c10, 1	@ flush_pmd", pmd);
 
- 	tlb_l2_op(TLB_L2CLEAN_FR, "c15, c9, 1  @ L2 flush_pmd", pmd);
 
- 	if (tlb_flag(TLB_WB))
 
- 		dsb();
 
- }
 
- static inline void clean_pmd_entry(void *pmd)
 
- {
 
- 	const unsigned int __tlb_flag = __cpu_tlb_flags;
 
- 	tlb_op(TLB_DCLEAN, "c7, c10, 1	@ flush_pmd", pmd);
 
- 	tlb_l2_op(TLB_L2CLEAN_FR, "c15, c9, 1  @ L2 flush_pmd", pmd);
 
- }
 
- #undef tlb_op
 
- #undef tlb_flag
 
- #undef always_tlb_flags
 
- #undef possible_tlb_flags
 
- /*
 
-  * Convert calls to our calling convention.
 
-  */
 
- #define local_flush_tlb_range(vma,start,end)	__cpu_flush_user_tlb_range(start,end,vma)
 
- #define local_flush_tlb_kernel_range(s,e)	__cpu_flush_kern_tlb_range(s,e)
 
- #ifndef CONFIG_SMP
 
- #define flush_tlb_all		local_flush_tlb_all
 
- #define flush_tlb_mm		local_flush_tlb_mm
 
- #define flush_tlb_page		local_flush_tlb_page
 
- #define flush_tlb_kernel_page	local_flush_tlb_kernel_page
 
- #define flush_tlb_range		local_flush_tlb_range
 
- #define flush_tlb_kernel_range	local_flush_tlb_kernel_range
 
- #else
 
- extern void flush_tlb_all(void);
 
- extern void flush_tlb_mm(struct mm_struct *mm);
 
- extern void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr);
 
- extern void flush_tlb_kernel_page(unsigned long kaddr);
 
- extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
 
- extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
 
- #endif
 
- /*
 
-  * If PG_dcache_clean is not set for the page, we need to ensure that any
 
-  * cache entries for the kernels virtual memory range are written
 
-  * back to the page. On ARMv6 and later, the cache coherency is handled via
 
-  * the set_pte_at() function.
 
-  */
 
- #if __LINUX_ARM_ARCH__ < 6
 
- extern void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr,
 
- 	pte_t *ptep);
 
- #else
 
- static inline void update_mmu_cache(struct vm_area_struct *vma,
 
- 				    unsigned long addr, pte_t *ptep)
 
- {
 
- }
 
- #endif
 
- #endif
 
- #endif /* CONFIG_MMU */
 
- #endif
 
 
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