1 /* 2 * MM context support for the Hexagon architecture 3 * 4 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 and 8 * only version 2 as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 18 * 02110-1301, USA. 19 */ 20 21 #ifndef _ASM_MMU_CONTEXT_H 22 #define _ASM_MMU_CONTEXT_H 23 24 #include <asm/setup.h> 25 #include <asm/page.h> 26 #include <asm/pgalloc.h> 27 #include <asm/mem-layout.h> 28 29 static inline void destroy_context(struct mm_struct *mm) 30 { 31 } 32 33 /* 34 * VM port hides all TLB management, so "lazy TLB" isn't very 35 * meaningful. Even for ports to architectures with visble TLBs, 36 * this is almost invariably a null function. 37 */ 38 static inline void enter_lazy_tlb(struct mm_struct *mm, 39 struct task_struct *tsk) 40 { 41 } 42 43 /* 44 * Architecture-specific actions, if any, for memory map deactivation. 45 */ 46 static inline void deactivate_mm(struct task_struct *tsk, 47 struct mm_struct *mm) 48 { 49 } 50 51 /** 52 * init_new_context - initialize context related info for new mm_struct instance 53 * @tsk: pointer to a task struct 54 * @mm: pointer to a new mm struct 55 */ 56 static inline int init_new_context(struct task_struct *tsk, 57 struct mm_struct *mm) 58 { 59 /* mm->context is set up by pgd_alloc */ 60 return 0; 61 } 62 63 /* 64 * Switch active mm context 65 */ 66 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 67 struct task_struct *tsk) 68 { 69 int l1; 70 71 /* 72 * For virtual machine, we have to update system map if it's been 73 * touched. 74 */ 75 if (next->context.generation < prev->context.generation) { 76 for (l1 = MIN_KERNEL_SEG; l1 <= max_kernel_seg; l1++) 77 next->pgd[l1] = init_mm.pgd[l1]; 78 79 next->context.generation = prev->context.generation; 80 } 81 82 __vmnewmap((void *)next->context.ptbase); 83 } 84 85 /* 86 * Activate new memory map for task 87 */ 88 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next) 89 { 90 unsigned long flags; 91 92 local_irq_save(flags); 93 switch_mm(prev, next, current_thread_info()->task); 94 local_irq_restore(flags); 95 } 96 97 /* Generic hooks for arch_dup_mmap and arch_exit_mmap */ 98 #include <asm-generic/mm_hooks.h> 99 100 #endif 101