source: trunk/kernel/mm/kcm.c @ 178

Last change on this file since 178 was 176, checked in by max@…, 7 years ago

detect use-after-frees

File size: 10.2 KB
RevLine 
[1]1/*
2 * kcm.c - Per cluster & per type Kernel Cache Manager access functions
[18]3 *
[1]4 * Author  Ghassan Almaless (2008,2009,2010,2011,2012)
[50]5 *         Alain Greiner    (2016,2017)
[1]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
[14]25#include <kernel_config.h>
[1]26#include <hal_types.h>
27#include <hal_special.h>
28#include <list.h>
29#include <printk.h>
30#include <bits.h>
31#include <ppm.h>
32#include <thread.h>
33#include <page.h>
34#include <cluster.h>
[7]35#include <kmem.h>
[1]36#include <kcm.h>
37
38//////////////////////////////////////////////////////////////////////////////////////
[7]39// This static function returns pointer on an allocated block from an active page.
[1]40// It returns NULL if no block available in selected page.
41// It changes the page status if required.
42//////////////////////////////////////////////////////////////////////////////////////
[50]43// @ kcm      : pointer on kcm allocator.
44// @ kcm_page : pointer on active kcm page to use.
[7]45/////////////////////////////////////////////////////////////////////////////////////
46static void * kcm_get_block( kcm_t      * kcm,
[50]47                             kcm_page_t * kcm_page )
[1]48{
[50]49        kcm_dmsg("\n[INFO] %s : enters for %s / page %x / count = %d / active = %d\n",
50                 __FUNCTION__ , kmem_type_str( kcm->type ) ,
[161]51                 (intptr_t)kcm_page , kcm_page->count , kcm_page->active );
[1]52
[50]53        assert( kcm_page->active , __FUNCTION__ , "kcm_page should be active" );
54
[20]55        // get first block available
[50]56        int32_t index = bitmap_ffs( kcm_page->bitmap , kcm->blocks_nr );
[1]57
[50]58        assert( (index != -1) , __FUNCTION__ , "kcm_page should not be full" );
[18]59
[20]60        // allocate block
[50]61        bitmap_clear( kcm_page->bitmap , index );
[7]62
[50]63        // increase kcm_page count
64        kcm_page->count ++;
[1]65
[50]66        // change the kcm_page to busy if no more free block in page
67        if( kcm_page->count >= kcm->blocks_nr )
[20]68        {
[161]69                kcm_page->active = 0;
[50]70                list_unlink( &kcm_page->list);
[1]71                kcm->active_pages_nr --;
72
[50]73                list_add_first( &kcm->busy_root , &kcm_page->list);
[1]74                kcm->busy_pages_nr ++;
[50]75                kcm_page->busy = 1;
[20]76        }
[1]77
[161]78        // compute return pointer
79        void * ptr = (void *)((intptr_t)kcm_page + CONFIG_KCM_SLOT_SIZE
80                     + (index * kcm->block_size) );
[1]81
[65]82        kcm_dmsg("\n[INFO] %s : allocated one block  %s / ptr = %p / page = %x / count = %d\n",
83                 __FUNCTION__ , kmem_type_str( kcm->type ) , ptr ,
[161]84                 (intptr_t)kcm_page , kcm_page->count );
[50]85
86        return ptr;
[161]87}
[50]88
[1]89/////////////////////////////////////////////////////////////////////////////////////
90// This static function releases a previously allocated block.
[50]91// It changes the kcm_page status if required.
[1]92/////////////////////////////////////////////////////////////////////////////////////
[7]93// @ kcm   : pointer on kcm allocator.
94// @ ptr   : pointer on block to be released.
95/////////////////////////////////////////////////////////////////////////////////////
96static void kcm_put_block ( kcm_t * kcm,
97                            void  * ptr )
[1]98{
[50]99        kcm_page_t * kcm_page;
[20]100        uint32_t     index;
[18]101
[161]102        // compute pointer on kcm_page from block pointer
[50]103        kcm_page = (kcm_page_t*)((intptr_t)ptr & ~CONFIG_PPM_PAGE_MASK);
[18]104
[161]105        // compute block index from block pointer
[50]106        index = ((uint8_t *)ptr - (uint8_t *)kcm_page - CONFIG_KCM_SLOT_SIZE) / kcm->block_size;
[18]107
[176]108        assert( !bitmap_state( kcm_page->bitmap , index ) , __FUNCTION__ , "page already freed" );
109        assert( (kcm_page->count > 0) , __FUNCTION__ , "count already zero" );
110
[50]111        bitmap_set( kcm_page->bitmap , index );
112        kcm_page->count --;
113
[20]114        // change the page to active if it was busy
[50]115        if( kcm_page->busy )
[1]116        {
[50]117                kcm_page->busy = 0;
118                list_unlink( &kcm_page->list );
[1]119                kcm->busy_pages_nr --;
120
[50]121                list_add_last( &kcm->active_root, &kcm_page->list );
[1]122                kcm->active_pages_nr ++;
[50]123                kcm_page->active = 1;
[1]124        }
125
[50]126        // change the kcm_page to free if last block in active page
127        if( (kcm_page->active) && (kcm_page->count == 0) )
[1]128        {
[50]129                kcm_page->active = 0;
130                list_unlink( &kcm_page->list);
[1]131                kcm->active_pages_nr --;
132
[50]133                list_add_first( &kcm->free_root , &kcm_page->list);
[1]134                kcm->free_pages_nr ++;
135        }
[161]136}
[1]137
138/////////////////////////////////////////////////////////////////////////////////////
[7]139// This static function allocates one page from PPM. It initializes
[50]140// the kcm_page descriptor, and introduces the new kcm_page into freelist.
[1]141/////////////////////////////////////////////////////////////////////////////////////
142static error_t freelist_populate( kcm_t * kcm )
143{
144        page_t     * page;
[50]145        kcm_page_t * kcm_page;
[20]146        kmem_req_t   req;
[1]147
[20]148        // get one page from local PPM
149        req.type  = KMEM_PAGE;
150        req.size  = 0;
151        req.flags = AF_KERNEL;
152        page = kmem_alloc( &req );
[18]153
[7]154        if( page == NULL )
155        {
[18]156                printk("\n[ERROR] in %s : failed to allocate page in cluster %d\n",
[20]157                       __FUNCTION__ , local_cxy );
158                return ENOMEM;
[7]159        }
160
[20]161        // get page base address
[53]162        kcm_page = (kcm_page_t *)ppm_page2vaddr( page );
[1]163
[20]164        // initialize KCM-page descriptor
[50]165        bitmap_set_range( kcm_page->bitmap , 0 , kcm->blocks_nr );
[1]166
[50]167        kcm_page->busy          = 0;
168        kcm_page->active        = 0;
169        kcm_page->count      = 0;
170        kcm_page->kcm           = kcm;
171        kcm_page->page          = page;
[1]172
[20]173        // introduce new page in free-list
[50]174        list_add_first( &kcm->free_root , &kcm_page->list );
[1]175        kcm->free_pages_nr ++;
[18]176
[1]177        return 0;
[161]178}
[1]179
180/////////////////////////////////////////////////////////////////////////////////////
[20]181// This private function gets one KCM page from the KCM freelist.
[1]182// It populates the freelist if required.
183/////////////////////////////////////////////////////////////////////////////////////
184static kcm_page_t * freelist_get( kcm_t * kcm )
185{
[7]186        error_t      error;
[50]187        kcm_page_t * kcm_page;
[1]188
[20]189        // get a new page from PPM if freelist empty
[1]190        if( kcm->free_pages_nr == 0 )
191        {
[20]192                error = freelist_populate( kcm );
193                if( error ) return NULL;
[1]194        }
195
[50]196        // get first KCM page from freelist and unlink it
197        kcm_page = LIST_FIRST( &kcm->free_root, kcm_page_t , list );
198        list_unlink( &kcm_page->list );
[1]199        kcm->free_pages_nr --;
200
[50]201        return kcm_page;
[161]202}
[1]203
[7]204//////////////////////////////
205void kcm_init( kcm_t    * kcm,
206                   uint32_t   type )
[1]207{
[161]208        // the kcm_page descriptor mut fit in the KCM slot
209        assert( (sizeof(kcm_page_t) <= CONFIG_KCM_SLOT_SIZE) ,
210                 __FUNCTION__ , "KCM slot too small\n" );
[1]211
[20]212        // initialize lock
[1]213        spinlock_init( &kcm->lock );
214
[20]215        // initialize KCM type
[1]216        kcm->type = type;
217
[20]218        // initialize KCM page lists
[1]219        kcm->free_pages_nr   = 0;
220        kcm->busy_pages_nr   = 0;
221        kcm->active_pages_nr = 0;
222        list_root_init( &kcm->free_root );
223        list_root_init( &kcm->busy_root );
224        list_root_init( &kcm->active_root );
225
[161]226        // initialize block size
[50]227        uint32_t block_size = ARROUND_UP( kmem_type_size( type ) , CONFIG_KCM_SLOT_SIZE );
[1]228        kcm->block_size = block_size;
[18]229
[50]230        // initialize number of blocks per page
231        uint32_t  blocks_nr = (CONFIG_PPM_PAGE_SIZE - CONFIG_KCM_SLOT_SIZE) / block_size;
[161]232        kcm->blocks_nr = blocks_nr;
[50]233
[20]234        kcm_dmsg("\n[INFO] %s : KCM %s initialised / block_size = %d / blocks_nr = %d\n",
[50]235                 __FUNCTION__ , kmem_type_str( type ) , kcm->block_size , kcm->blocks_nr );
[161]236}
[1]237
238///////////////////////////////
239void kcm_destroy( kcm_t * kcm )
240{
[50]241        kcm_page_t   * kcm_page;
[1]242        list_entry_t * iter;
[18]243
[20]244        // get KCM lock
[1]245        spinlock_lock( &kcm->lock );
246
[20]247        // release all free pages
[1]248        LIST_FOREACH( &kcm->free_root , iter )
249        {
[50]250                kcm_page = (kcm_page_t *)LIST_ELEMENT( iter , kcm_page_t , list );
[1]251                list_unlink( iter );
252                kcm->free_pages_nr --;
[50]253                ppm_free_pages( kcm_page->page );
[1]254        }
255
[20]256        // release all active pages
[1]257        LIST_FOREACH( &kcm->active_root , iter )
258        {
[50]259                kcm_page = (kcm_page_t *)LIST_ELEMENT( iter , kcm_page_t , list );
[1]260                list_unlink( iter );
261                kcm->free_pages_nr --;
[50]262                ppm_free_pages( kcm_page->page );
[1]263        }
264
[20]265        // release all busy pages
[1]266        LIST_FOREACH( &kcm->busy_root , iter )
267        {
[50]268                kcm_page = (kcm_page_t *)LIST_ELEMENT( iter , kcm_page_t , list );
[1]269                list_unlink( iter );
270                kcm->free_pages_nr --;
[50]271                ppm_free_pages( kcm_page->page );
[1]272        }
273
[20]274        // release KCM lock
275        spinlock_unlock( &kcm->lock );
[161]276}
[1]277
278///////////////////////////////
279void * kcm_alloc( kcm_t * kcm )
280{
[50]281        kcm_page_t * kcm_page;
[1]282        void       * ptr = NULL;   // pointer on block
283
[20]284        // get lock
[1]285        spinlock_lock( &kcm->lock );
[18]286
[20]287        // get an active page
288        if( list_is_empty( &kcm->active_root ) )  // no active page => get one
289        {
290                // get a page from free list
[50]291                kcm_page = freelist_get( kcm );
[7]292
[50]293                if( kcm_page == NULL ) return NULL;
294
[20]295                // insert page in active list
[50]296                list_add_first( &kcm->active_root , &kcm_page->list );
[20]297                kcm->active_pages_nr ++;
[161]298                kcm_page->active = 1;
[50]299
[161]300                kcm_dmsg("\n[INFO] %s : enters for type %s at cycle %d / new page = %x / count = %d\n",
[101]301                         __FUNCTION__ , kmem_type_str( kcm->type ) , hal_get_cycles() ,
[161]302                         (intptr_t)kcm_page , kcm_page->count );
[50]303
[20]304        }
[50]305        else                                    // get first page from active list
[20]306        {
[50]307                // get page pointer from active list
308                kcm_page = (kcm_page_t *)LIST_FIRST( &kcm->active_root , kcm_page_t , list );
[7]309
[50]310                kcm_dmsg("\n[INFO] %s : enters for type %s at cycle %d / page = %x / count = %d\n",
[161]311                         __FUNCTION__ , kmem_type_str( kcm->type ) , hal_get_cycles() ,
312                         (intptr_t)kcm_page , kcm_page->count );
[20]313        }
[1]314
[20]315        // get a block from selected active page
316        // cannot fail, as an active page cannot be full...
[50]317        ptr  = kcm_get_block( kcm , kcm_page );
[7]318
[20]319        // release lock
[50]320        spinlock_unlock( &kcm->lock );
[1]321
322        return ptr;
[161]323}
[1]324
325///////////////////////////
326void kcm_free( void * ptr )
327{
[50]328        kcm_page_t * kcm_page;
[1]329        kcm_t      * kcm;
[18]330
[50]331        assert( (ptr != NULL) , __FUNCTION__ , "pointer cannot be NULL" );
[18]332
[50]333        kcm_page = (kcm_page_t *)((intptr_t)ptr & ~CONFIG_PPM_PAGE_MASK);
334        kcm      = kcm_page->kcm;
[1]335
[20]336        // get lock
[1]337        spinlock_lock( &kcm->lock );
338
[20]339        // release block
[7]340        kcm_put_block( kcm , ptr );
[1]341
[20]342        // release lock
[1]343        spinlock_unlock( &kcm->lock );
[161]344}
[1]345
346////////////////////////////
347void kcm_print (kcm_t * kcm)
348{
[7]349        printk("*** KCM type = %s / free_pages = %d / busy_pages = %d / active_pages = %d\n",
[20]350               kmem_type_str( kcm->type ) ,
351               kcm->free_pages_nr ,
352               kcm->busy_pages_nr ,
353               kcm->active_pages_nr );
[1]354}
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