[1] | 1 | /* |
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| 2 | * vmm.h - virtual memory management related operations |
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| 3 | * |
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| 4 | * Authors Ghassan Almaless (2008,2009,2010,2011, 2012) |
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| 5 | * Mohamed Lamine Karaoui (2015) |
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[23] | 6 | * Alain Greiner (2016,2017) |
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[18] | 7 | * |
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[1] | 8 | * Copyright (c) UPMC Sorbonne Universites |
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| 9 | * |
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| 10 | * This file is part of ALMOS-MKH. |
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| 11 | * |
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| 12 | * ALMOS-MKH is free software; you can redistribute it and/or modify it |
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| 13 | * under the terms of the GNU General Public License as published by |
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| 14 | * the Free Software Foundation; version 2.0 of the License. |
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| 15 | * |
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| 16 | * ALMOS-MKH is distributed in the hope that it will be useful, but |
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| 17 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 19 | * General Public License for more details. |
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| 20 | * |
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| 21 | * You should have received a copy of the GNU General Public License |
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| 22 | * along with ALMOS-MKH; if not, write to the Free Software Foundation, |
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| 23 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
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| 24 | */ |
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| 25 | |
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| 26 | #ifndef _VMM_H_ |
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| 27 | #define _VMM_H_ |
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| 28 | |
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| 29 | #include <hal_types.h> |
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| 30 | #include <bits.h> |
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| 31 | #include <list.h> |
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| 32 | #include <grdxt.h> |
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| 33 | #include <spinlock.h> |
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| 34 | #include <hal_gpt.h> |
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| 35 | #include <vseg.h> |
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| 36 | #include <page.h> |
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| 37 | |
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| 38 | /**** Forward declarations ****/ |
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| 39 | |
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| 40 | struct process_s; |
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| 41 | |
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| 42 | /********************************************************************************************* |
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| 43 | * This structure defines the STACK allocator used by the VMM to dynamically allocate |
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| 44 | * STACK vsegs requested or released by the user process. |
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| 45 | * This allocator handles a fixed size array of fixed size slots stores in the STACK zone. |
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| 46 | * The stack size and the number of slots are defined by the CONFIG_VMM_STACK_SIZE, and |
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| 47 | * CONFIG_THREAD |
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| 48 | * Each slot can contain one user stack vseg. The first page in the slot is not allocated |
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| 49 | * to detect stack overflow. |
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| 50 | * The slot index can be computed form the slot base address, and reversely. |
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| 51 | * All allocation / release operations are registered in the stack_bitmap, that completely |
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[18] | 52 | * define the STACK zone state. |
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[1] | 53 | * In this implementation, the max number of slots is 32. |
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| 54 | ********************************************************************************************/ |
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| 55 | |
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| 56 | typedef struct stack_mgr_s |
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| 57 | { |
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| 58 | spinlock_t lock; /*! lock protecting STACK allocator */ |
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| 59 | vpn_t vpn_base; /*! first page of STACK zone */ |
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| 60 | bitmap_t bitmap; /*! bit bector of allocated stacks */ |
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| 61 | } |
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| 62 | stack_mgr_t; |
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| 63 | |
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| 64 | /********************************************************************************************* |
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| 65 | * This structure defines the MMAP allocator used by the VMM to dynamically allocate |
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| 66 | * MMAP vsegs requested or released by an user process. |
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[18] | 67 | * This allocator should be only used in the reference cluster. |
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| 68 | * - allocation policy : all allocated vsegs occupy an integer number of pages that is |
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[1] | 69 | * power of 2, and are aligned on a page boundary. The requested number of pages is |
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[18] | 70 | * rounded if required. The first_free_vpn variable defines completely the MMAP zone state. |
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[1] | 71 | * It is never decremented, as the released vsegs are simply registered in a zombi_list. |
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[18] | 72 | * The relevant zombi_list is checked first for each allocation request. |
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[1] | 73 | * - release policy : a released MMAP vseg is registered in an array of zombi_lists. |
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| 74 | * This array is indexed by ln(number of pages), and each entry contains the root of |
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| 75 | * a local list of zombi vsegs that have the same size. The physical memory allocated |
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| 76 | * for a zombi vseg descriptor is not released, to use the "list" field. |
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| 77 | * This physical memory allocated for MMAP vseg descriptors is actually released |
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| 78 | * when the VMM is destroyed. |
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| 79 | ********************************************************************************************/ |
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| 80 | |
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| 81 | typedef struct mmap_mgr_s |
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| 82 | { |
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| 83 | spinlock_t lock; /*! lock protecting MMAP allocator */ |
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| 84 | vpn_t vpn_base; /*! first page of MMAP zone */ |
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| 85 | vpn_t vpn_size; /*! number of pages in MMAP zone */ |
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| 86 | vpn_t first_free_vpn; /*! first free page in MMAP zone */ |
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| 87 | list_entry_t zombi_list[32]; /*! array of roots of released vsegs lists */ |
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| 88 | } |
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| 89 | mmap_mgr_t; |
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| 90 | |
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| 91 | /********************************************************************************************* |
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| 92 | * This structure defines the Virtual Memory Manager for a given process in a given cluster. |
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| 93 | * This local VMM provides three main services: |
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| 94 | * 1) It registers all vsegs statically or dynamically defined in the vseg list, |
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| 95 | * and in the associated radix-tree. |
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| 96 | * 2) It allocates virtual memory space for the STACKS and MMAP vsegs, |
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[18] | 97 | * using dedicated allocators. |
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[1] | 98 | * 3) It contains the local copy of the generic page table descriptor. |
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| 99 | ********************************************************************************************/ |
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| 100 | |
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| 101 | typedef struct vmm_s |
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| 102 | { |
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| 103 | rwlock_t vsegs_lock; /*! lock protecting the vsegs list & radix tree */ |
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| 104 | list_entry_t vsegs_root; /*! all vsegs in same process and same cluster */ |
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[23] | 105 | uint32_t vsegs_nr; /*! total number of local vsegs */ |
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[1] | 106 | grdxt_t grdxt; /*! embedded generic vsegs radix tree (key is vpn) */ |
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| 107 | |
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| 108 | gpt_t gpt; /*! embedded generic page table descriptor */ |
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| 109 | |
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| 110 | stack_mgr_t stack_mgr; /*! embedded STACK vsegs allocator */ |
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| 111 | mmap_mgr_t mmap_mgr; /*! embedded MMAP vsegs allocator */ |
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| 112 | |
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| 113 | uint32_t pgfault_nr; /*! page fault counter */ |
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| 114 | uint32_t u_err_nr; /*! TODO ??? [AG] */ |
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| 115 | uint32_t m_err_nr; /*! TODO ??? [AG] */ |
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| 116 | |
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| 117 | vpn_t kent_vpn_base; /*! kentry vseg first page */ |
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| 118 | vpn_t args_vpn_base; /*! args vseg first page */ |
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| 119 | vpn_t envs_vpn_base; /*! envs zone first page */ |
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| 120 | vpn_t heap_vpn_base; /*! envs zone first page */ |
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| 121 | vpn_t code_vpn_base; /*! code zone first page */ |
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| 122 | vpn_t data_vpn_base; /*! data zone first page */ |
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| 123 | |
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| 124 | intptr_t entry_point; /*! main thread entry point */ |
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| 125 | |
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| 126 | vseg_t * heap_vseg; /*! pointer on local heap vseg descriptor */ |
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| 127 | } |
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| 128 | vmm_t; |
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| 129 | |
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| 130 | /********************************************************************************************* |
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| 131 | * This structure is used to store the arguments of the mmap() system call. |
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| 132 | ********************************************************************************************/ |
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| 133 | |
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| 134 | typedef struct mmap_attr_s |
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| 135 | { |
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[18] | 136 | void * addr; /*! requested virtual address (unused : should be NULL) */ |
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[1] | 137 | uint32_t length; /*! requested vseg size (bytes) */ |
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| 138 | uint32_t prot; /*! access modes */ |
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| 139 | uint32_t flags; /*! only MAP_FILE / MAP_ANON / MAP_PRIVATE / MAP_SHARED */ |
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| 140 | fdid_t fdid; /*! file descriptor index (if MAP_FILE is set) */ |
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| 141 | int32_t offset; /*! file offset (if MAP_FILE is set) */ |
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| 142 | } |
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| 143 | mmap_attr_t; |
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| 144 | |
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| 145 | /********************************************************************************************* |
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| 146 | * This function initialises the virtual memory manager attached to a process. |
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| 147 | * - It initializes the VSL (list of vsegs and associated radix tree). |
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| 148 | * - It initializes the generic page table (empty). |
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| 149 | * - It initializes the STAK and MMAP allocators. |
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| 150 | * - It registers the "kentry", "args", "envs" and "heap" vsegs in the vsegs list. |
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| 151 | * Any error in this function gives a kernel panic. |
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| 152 | ********************************************************************************************* |
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| 153 | * @ process : pointer on process descriptor |
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| 154 | ********************************************************************************************/ |
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| 155 | void vmm_init( struct process_s * process ); |
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| 156 | |
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| 157 | /********************************************************************************************* |
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[23] | 158 | * This function copies the content of a source VMM to a destination VMM. |
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| 159 | ********************************************************************************************* |
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| 160 | * @ dst_process : pointer on destination process descriptor. |
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| 161 | * @ src_process : pointer on source process descriptor. |
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| 162 | * @ return 0 if success / return ENOMEM if failure. |
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| 163 | ********************************************************************************************/ |
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| 164 | error_t vmm_copy( struct process_s * dst_process, |
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| 165 | struct process_s * src_process ); |
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| 166 | |
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| 167 | /********************************************************************************************* |
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[1] | 168 | * This function removes all vsegs registered in in a virtual memory manager, |
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[18] | 169 | * and releases the memory allocated to the local generic page table. |
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[1] | 170 | ********************************************************************************************* |
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[23] | 171 | * @ process : pointer on process descriptor. |
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[1] | 172 | ********************************************************************************************/ |
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| 173 | void vmm_destroy( struct process_s * process ); |
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| 174 | |
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| 175 | /********************************************************************************************* |
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[18] | 176 | * This function scans the list of vsegs registered in the VMM of a given process descriptor |
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[1] | 177 | * to check if a given virtual region (defined by a base and size) overlap an existing vseg. |
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| 178 | ********************************************************************************************* |
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| 179 | * @ process : pointer on process descriptor. |
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| 180 | * @ base : region virtual base address. |
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| 181 | * @ size : region size (bytes). |
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| 182 | * @ returns NULL if no conflict / return conflicting vseg pointer if conflict. |
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| 183 | ********************************************************************************************/ |
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| 184 | vseg_t * vmm_check_conflict( struct process_s * process, |
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| 185 | vpn_t base, |
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| 186 | vpn_t size ); |
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| 187 | |
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| 188 | /********************************************************************************************* |
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[18] | 189 | * This function allocates memory for a vseg descriptor, initialises it, and register it |
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[1] | 190 | * in the VMM of the process. It checks the collision with pre-existing vsegs in VMM. |
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| 191 | * For STACK and MMAP types vseg, it does not use the base argument, but uses the VMM STACK |
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| 192 | * and MMAP specific allocators to get a base address in virtual space. |
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[18] | 193 | * To comply with the "on-demand" paging policy, this function does NOT modify the |
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[1] | 194 | * page table, and does not allocate physical memory for vseg data. |
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| 195 | ********************************************************************************************* |
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| 196 | * @ vmm : pointer on process descriptor. |
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| 197 | * @ base : vseg base address |
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| 198 | * @ size : vseg size (bytes) |
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| 199 | * @ type : vseg type |
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| 200 | * @ returns pointer on vseg if success / returns NULL if no memory or conflict. |
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| 201 | ********************************************************************************************/ |
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| 202 | vseg_t * vmm_create_vseg( struct process_s * process, |
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[18] | 203 | intptr_t base, |
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| 204 | intptr_t size, |
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[1] | 205 | uint32_t type ); |
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| 206 | |
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| 207 | /********************************************************************************************* |
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[18] | 208 | * This function removes a vseg identified by it's pointer from the VMM of the calling process. |
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[1] | 209 | * - If the vseg has not the STACK or MMAP type, it is removed from the vsegs list, |
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| 210 | * and the physical memory allocated to vseg descriptor is released to KMEM. |
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| 211 | * - If the vseg has the STACK type, it is removed from the vsegs list, the physical memory |
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| 212 | * allocated to vseg descriptor is released to KMEM, and the stack slot is returned to the |
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| 213 | * VMM STACK allocator. |
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| 214 | * - If the vseg has the MMAP type, it is removed from the vsegs list and is registered |
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| 215 | * in the zombi_list of the VMM MMAP allocator for future reuse. The physical memory |
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| 216 | * allocated to vseg descriptor is NOT released to KMEM. |
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| 217 | ********************************************************************************************* |
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| 218 | * @ vseg : pointer on vseg to be removed. |
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| 219 | ********************************************************************************************/ |
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| 220 | void vmm_remove_vseg( vseg_t * vseg ); |
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| 221 | |
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| 222 | /********************************************************************************************* |
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[18] | 223 | * This function allocates physical memory from the local cluster to map all PTEs |
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[1] | 224 | * of a "kernel" vseg (type KCODE , KDATA, or KDEV) in the page table of process_zero. |
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[68] | 225 | * WARNING : It should not be used for "user" vsegs, that must be mapped using the |
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[1] | 226 | * "on-demand-paging" policy. |
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| 227 | ********************************************************************************************* |
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| 228 | * @ vseg : pointer on the vseg to be mapped. |
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| 229 | * @ attr : GPT attributes to be set for all vseg pages. |
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| 230 | * @ returns 0 if success / returns ENOMEM if no memory |
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| 231 | ********************************************************************************************/ |
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[68] | 232 | error_t vmm_map_kernel_vseg( vseg_t * vseg, |
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| 233 | uint32_t attr ); |
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[1] | 234 | |
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| 235 | /********************************************************************************************* |
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[18] | 236 | * This function unmaps all PTEs of a given vseg, in the generic page table associated |
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[1] | 237 | * to a given process descriptor, and releases the corresponding physical memory. |
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| 238 | * It can be used for any type of vseg. |
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| 239 | ********************************************************************************************* |
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| 240 | * @ process : pointer on process descriptor. |
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| 241 | * @ vseg : pointer on the vseg to be unmapped. |
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| 242 | ********************************************************************************************/ |
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| 243 | void vmm_unmap_vseg( struct process_s * process, |
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| 244 | vseg_t * vseg ); |
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| 245 | |
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| 246 | /********************************************************************************************* |
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[18] | 247 | * This function removes a given region (defined by a base address and a size) from |
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[1] | 248 | * the VMM of a given process descriptor. This can modify several vsegs: |
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| 249 | * (a) if the region is not entirely mapped in an existing vseg, it's an error. |
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| 250 | * (b) if the region has same base and size as an existing vseg, the vseg is removed. |
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| 251 | * (c) if the removed region cut the vseg in two parts, it is removed and re-created. |
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| 252 | * (d) if the removed region cut the vseg in three parts, it is removed, and two are created. |
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| 253 | * TODO : cases (c) and (d) are not implemented [AG] |
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| 254 | ********************************************************************************************* |
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| 255 | * @ process : pointer on process descriptor |
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| 256 | * @ base : vseg base address |
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| 257 | * @ size : vseg size (bytes) |
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| 258 | ********************************************************************************************/ |
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| 259 | error_t vmm_resize_vseg( struct process_s * process, |
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| 260 | intptr_t base, |
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| 261 | intptr_t size ); |
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| 262 | |
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| 263 | /********************************************************************************************* |
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[388] | 264 | * This function checks that a given virtual address is contained in a registered vseg. |
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| 265 | * - if the vseg is registered in local process VMM, it returns the local vseg pointer. |
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| 266 | * - if the vseg is missing in local VMM, it uses a RPC to get it from the reference cluster, |
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| 267 | * register it in local VMM and returns the local vseg pointer, if success. |
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| 268 | * - if the vseg is missing in reference VMM, it returns an user error. |
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| 269 | * It creates a kernel panic if there is not enough memory to create a new vseg descriptor |
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| 270 | * in the cluster containing the calling thread. |
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[1] | 271 | ********************************************************************************************* |
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[388] | 272 | * @ process : [in] pointer on process descriptor |
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| 273 | * @ vaddr : [in] virtual address |
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| 274 | * @ vseg : [out] pointer on found vseg |
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| 275 | * @ returns 0 if success / returns -1 if user error. |
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[1] | 276 | *********************************************************************************************/ |
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[388] | 277 | error_t vmm_get_vseg( struct process_s * process, |
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| 278 | intptr_t vaddr, |
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[394] | 279 | vseg_t ** vseg ); |
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[1] | 280 | |
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| 281 | /********************************************************************************************* |
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[23] | 282 | * This function is called by the generic exception handler when a page fault |
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| 283 | * has been detected in a given cluster. |
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[1] | 284 | * If the local cluster is not the reference cluster, it send a RPC_VMM_GET_PTE |
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| 285 | * to the reference cluster to get the missing PTE attributes and PPN, and update |
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| 286 | * the local page table. If the local cluster is the reference, it call directly |
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| 287 | * the vmm_get_pte() function. |
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| 288 | ********************************************************************************************* |
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| 289 | * @ process : pointer on process descriptor. |
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| 290 | * @ vseg : pointer on involved vseg. |
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| 291 | * @ vpn : VPN of the missing PTE. |
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| 292 | * @ returns 0 if success / returns ENOMEM if no memory. |
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| 293 | ********************************************************************************************/ |
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| 294 | error_t vmm_handle_page_fault( struct process_s * process, |
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| 295 | vseg_t * vseg, |
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[18] | 296 | vpn_t vpn ); |
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[1] | 297 | |
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| 298 | /********************************************************************************************* |
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| 299 | * This function returns in the "attr" and "ppn" arguments the PTE associated to a given |
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[313] | 300 | * VPN for a given process. This function must be called by a thread running in the |
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| 301 | * reference cluster. To get the PTE from another cluster, use the RPC_VMM_GET_PTE. |
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[1] | 302 | * The vseg containing the searched VPN should be registered in the reference VMM. |
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| 303 | * If the PTE in the reference page table is unmapped, this function allocates the missing |
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[388] | 304 | * physical page from the target cluster defined by the vseg type, initialize it, |
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[313] | 305 | * and update the reference page table. It calls the RPC_PMEM_GET_PAGES to get and |
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| 306 | * initialize the missing physical page, if the target cluster is not the reference cluster. |
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[1] | 307 | ********************************************************************************************* |
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| 308 | * @ process : [in] pointer on process descriptor. |
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| 309 | * @ vpn : [in] VPN defining the missing PTE. |
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| 310 | * @ attr : [out] PTE attributes. |
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| 311 | * @ ppn : [out] PTE ppn. |
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| 312 | * @ returns 0 if success / returns ENOMEM if error. |
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| 313 | ********************************************************************************************/ |
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| 314 | error_t vmm_get_pte( struct process_s * process, |
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| 315 | vpn_t vpn, |
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| 316 | uint32_t * attr, |
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| 317 | ppn_t * ppn ); |
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| 318 | |
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| 319 | /********************************************************************************************* |
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[313] | 320 | * This function is called by the vmm_get_pte() function. |
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| 321 | * Depending on the vseg type, defined by the <vseg> argument, it returns the PPN |
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| 322 | * (Physical Page Number) associated to a missing page defined by the <vpn> argument. |
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| 323 | * - For the VSEG_TYPE_FILE, it returns the physical page from the file mapper. |
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| 324 | * For all other types, it allocates a new physical page from the cluster defined |
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| 325 | * by the <vseg->cxy> field, or by the <vpn> MSB bits for a distributed vseg. |
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| 326 | * - For the VSEG_TYPE_CODE and VSEG_TYPE_DATA types, the allocated page is initialized |
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| 327 | * from the .elf file mapper. For others vseg types it is not initialised. |
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| 328 | ********************************************************************************************* |
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| 329 | * @ vseg : local pointer on vseg containing the mising page. |
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| 330 | * @ vpn : Virtual Page Number identifying the missing page. |
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| 331 | * @ ppn : [out] returned Physical Page Number. |
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| 332 | ********************************************************************************************/ |
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| 333 | error_t vmm_get_one_ppn( vseg_t * vseg, |
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| 334 | vpn_t vpn, |
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| 335 | ppn_t * ppn ); |
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| 336 | |
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| 337 | /********************************************************************************************* |
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[18] | 338 | * This function makes the virtual to physical address translation, using the calling |
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[68] | 339 | * process page table. It uses identity mapping if required by the <ident> argument. |
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[23] | 340 | * This address translation is required to configure the peripherals having a DMA |
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| 341 | * capability, or to implement the software L2/L3 cache cohérence, using the MMC device |
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| 342 | * synchronisation primitives. |
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| 343 | * WARNING : the <ident> value must be defined by the CONFIG_KERNEL_IDENTITY_MAP parameter. |
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[1] | 344 | ********************************************************************************************* |
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| 345 | * @ ident : [in] uses identity mapping if true. |
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| 346 | * @ ptr : [in] virtual address. |
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| 347 | * @ paddr : [out] pointer on buffer for physical address. |
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| 348 | * @ returns 0 if success / returns ENOMEM if error. |
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| 349 | ********************************************************************************************/ |
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| 350 | error_t vmm_v2p_translate( bool_t ident, |
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| 351 | void * ptr, |
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| 352 | paddr_t * paddr ); |
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| 353 | |
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| 354 | |
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| 355 | |
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| 356 | #endif /* _VMM_H_ */ |
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