source: trunk/kernel/mm/ppm.c @ 313

Last change on this file since 313 was 313, checked in by alain, 5 years ago

RSeveral modifs in the page-fault handling.

File size: 6.8 KB
Line 
1/*
2 * ppm.c - Per-cluster Physical Pages Manager implementation
3 *
4 * Authors  Ghassan Almaless (2008,2009,2010,2011,2012)
5 *          Alain Greiner    (2016,2017)
6 *
7 * Copyright (c) UPMC Sorbonne Universites
8 *
9 * This file is part of ALMOS-MKH.
10 *
11 * ALMOS-MKH.is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; version 2.0 of the License.
14 *
15 * ALMOS-MKH.is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with ALMOS-MKH.; if not, write to the Free Software Foundation,
22 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
25#include <kernel_config.h>
26#include <hal_types.h>
27#include <hal_special.h>
28#include <printk.h>
29#include <list.h>
30#include <bits.h>
31#include <page.h>
32#include <spinlock.h>
33#include <thread.h>
34#include <cluster.h>
35#include <kmem.h>
36#include <process.h>
37#include <dqdt.h>
38#include <ppm.h>
39
40////////////////////////////////////////////////
41inline bool_t ppm_page_is_valid( page_t * page )
42{
43        ppm_t    * ppm  = &LOCAL_CLUSTER->ppm;
44        uint32_t   pgnr = (uint32_t)( page - ppm->pages_tbl );
45        return (pgnr <= ppm->pages_nr);
46}
47
48
49/////////////////////////////////////////////
50inline void * ppm_page2vaddr( page_t * page )
51{
52        ppm_t * ppm = &LOCAL_CLUSTER->ppm;
53        return ppm->vaddr_base + ((page - ppm->pages_tbl) << CONFIG_PPM_PAGE_SHIFT);
54}
55
56//////////////////////////////////////////////
57inline page_t * ppm_vaddr2page( void * vaddr )
58{
59        ppm_t * ppm = &LOCAL_CLUSTER->ppm;
60        return ppm->pages_tbl + (vaddr - ppm->vaddr_base);
61}
62
63///////////////////////////////////////////
64void ppm_free_pages_nolock( page_t * page )
65{
66        page_t   * buddy;            // searched buddy page descriptor
67        uint32_t   buddy_index;      // buddy page index
68        page_t   * current;          // current (merged) page descriptor
69        uint32_t   current_index;    // current (merged) page index
70        uint32_t   current_order;    // current (merged) page order
71
72        ppm_t    * ppm         = &LOCAL_CLUSTER->ppm;
73        page_t   * pages_tbl   = ppm->pages_tbl;
74
75        assert( !page_is_flag( page , PG_FREE ) , __FUNCTION__ , "page already freed" );
76        assert( !page_is_flag( page , PG_RESERVED ) , __FUNCTION__ , "freeing reserved page" );
77
78        // update released page descriptor flags
79        page_set_flag( page , PG_FREE );
80
81        // search the buddy page descriptor
82        // - merge with current page descriptor if found
83        // - exit to release the current page descriptor if not found
84        current       = page ,
85        current_index = (uint32_t)(page - ppm->pages_tbl);
86        for( current_order = page->order ;
87             current_order < CONFIG_PPM_MAX_ORDER ;
88             current_order++ )
89        {
90                buddy_index = current_index ^ (1 << current_order);
91                buddy       = pages_tbl + buddy_index;
92
93                if( !page_is_flag( buddy , PG_FREE ) || (buddy->order != current_order) ) break;
94
95                // remove buddy from free list
96                list_unlink( &buddy->list );
97                ppm->free_pages_nr[current_order] --;
98
99                // merge buddy with current
100                buddy->order = 0;
101                current_index &= buddy_index;
102        }
103
104        // update merged page descriptor order
105        current        = pages_tbl + current_index;
106        current->order = current_order;
107
108        // insert current in free list
109        list_add_first( &ppm->free_pages_root[current_order] , &current->list );
110        ppm->free_pages_nr[current_order] ++;
111}
112
113////////////////////////////////////////////
114page_t * ppm_alloc_pages( uint32_t   order )
115{
116        uint32_t   current_order;
117        page_t   * remaining_block;
118        uint32_t   current_size;
119
120        ppm_t    * ppm = &LOCAL_CLUSTER->ppm;
121
122        assert( (order < CONFIG_PPM_MAX_ORDER) , __FUNCTION__ , "illegal order argument" );
123
124        page_t * block = NULL;
125
126        ppm_dmsg("\n[INFO] %s : enters / order = %d\n",
127                 __FUNCTION__ , order );
128
129        // take lock protecting free lists
130        spinlock_lock( &ppm->free_lock );
131
132        // find a free block equal or larger to requested size
133        for( current_order = order ; current_order < CONFIG_PPM_MAX_ORDER ; current_order ++ )
134        {
135                if( !list_is_empty( &ppm->free_pages_root[current_order] ) )
136                {
137                        block = LIST_FIRST( &ppm->free_pages_root[current_order] , page_t , list );
138                        list_unlink( &block->list );
139                        break;
140                }
141        }
142
143        if( block == NULL ) // return failure
144        {
145                // release lock protecting free lists
146                spinlock_unlock( &ppm->free_lock );
147
148                return NULL;
149        }
150
151        // update free-lists after removing a block
152        ppm->free_pages_nr[current_order] --;
153        current_size = (1 << current_order);
154
155        // split the removed block in smaller sub-blocks if required
156        // and update the free-lists accordingly
157        while( current_order > order )
158        {
159                current_order --;
160                current_size >>= 1;
161
162                remaining_block = block + current_size;
163                remaining_block->order = current_order;
164
165                list_add_first( &ppm->free_pages_root[current_order] , &remaining_block->list );
166                ppm->free_pages_nr[current_order] ++;
167        }
168
169        // update page descriptor
170        page_clear_flag( block , PG_FREE );
171        page_refcount_up( block );
172        block->order = order;
173
174        // release lock protecting free lists
175        spinlock_unlock( &ppm->free_lock );
176
177        ppm_dmsg("\n[INFO] %s : base = %x / order = %d\n",
178                 __FUNCTION__ , (uint32_t)ppm_page2base( block ) , order );
179
180        return block;
181}
182
183
184////////////////////////////////////
185void ppm_free_pages( page_t * page )
186{
187        ppm_t * ppm = &LOCAL_CLUSTER->ppm;
188
189        // get lock protecting free_pages[] array
190        spinlock_lock( &ppm->free_lock );
191
192        ppm_free_pages_nolock( page );
193
194        // release lock protecting free_pages[] array
195        spinlock_unlock( &ppm->free_lock );
196}
197
198////////////////////////////
199void ppm_print( ppm_t * ppm,
200                char  * string )
201{
202        uint32_t       order;
203        list_entry_t * iter;
204        page_t       * page;
205
206        // get lock protecting free lists
207        spinlock_lock( &ppm->free_lock );
208
209        printk("\n***  PPM in cluster %x : %d pages / &pages_tbl = %x / vaddr_base = %x ***\n",
210               local_cxy , ppm->pages_nr , (intptr_t)ppm->pages_tbl , (intptr_t)ppm->vaddr_base );
211
212        for( order = 0 ; order < CONFIG_PPM_MAX_ORDER ; order++ )
213        {
214                printk("- order = %d / free_pages = %d  [",
215                       order , ppm->free_pages_nr[order] );
216
217                LIST_FOREACH( &ppm->free_pages_root[order] , iter )
218                {
219                        page = LIST_ELEMENT( iter , page_t , list );
220                        printk("%d," , page - ppm->pages_tbl );
221                }
222
223                printk("]\n", NULL );
224        }
225
226        // release lock protecting free lists
227        spinlock_unlock( &ppm->free_lock );
228}
229
230///////////////////////////////////////
231error_t ppm_assert_order( ppm_t * ppm )
232{
233        uint32_t       order;
234        list_entry_t * iter;
235        page_t       * page;
236
237        for(order=0; order < CONFIG_PPM_MAX_ORDER; order++)
238        {
239                if( list_is_empty( &ppm->free_pages_root[order] ) ) continue;
240
241                LIST_FOREACH( &ppm->free_pages_root[order] , iter )
242                {
243                        page = LIST_ELEMENT( iter , page_t , list );
244
245                        if( page->order != order )  return -1;
246                }
247        }
248
249        return 0;
250}
251
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