source: trunk/kernel/mm/mapper.c @ 407

Last change on this file since 407 was 407, checked in by alain, 4 years ago

First implementation of fork/exec.

File size: 15.1 KB
Line 
1/*
2 * mapper.c - Map memory, file or device in process virtual address space.
3 *
4 * Authors   Mohamed Lamine Karaoui (2015)
5 *           Alain Greiner (2016)
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 <hal_uspace.h>
29#include <grdxt.h>
30#include <rwlock.h>
31#include <printk.h>
32#include <memcpy.h>
33#include <thread.h>
34#include <core.h>
35#include <process.h>
36#include <kmem.h>
37#include <kcm.h>
38#include <page.h>
39#include <cluster.h>
40#include <vfs.h>
41#include <mapper.h>
42
43//////////////////////////////////////////////
44mapper_t * mapper_create( vfs_fs_type_t type )
45{
46    mapper_t * mapper;
47    kmem_req_t req;
48    error_t    error;
49
50    // allocate memory for associated mapper
51    req.type  = KMEM_MAPPER;
52    req.size  = sizeof(mapper_t);
53    req.flags = AF_KERNEL | AF_ZERO;
54    mapper    = (mapper_t *)kmem_alloc( &req );
55
56    if( mapper == NULL )
57    {
58        printk("\n[ERROR] in %s : no memory for mapper descriptor\n", __FUNCTION__ );
59        return NULL;
60    }
61
62    // initialize refcount & inode
63    mapper->refcount = 0;
64    mapper->inode    = NULL;
65
66    // initialize radix tree
67    error = grdxt_init( &mapper->radix,
68                        CONFIG_VMM_GRDXT_W1,
69                        CONFIG_VMM_GRDXT_W2,
70                        CONFIG_VMM_GRDXT_W3 );
71
72    if( error )
73    {
74        printk("\n[ERROR] in %s : cannot initialize radix tree\n", __FUNCTION__ );
75        req.type  = KMEM_MAPPER;
76        req.ptr   = mapper;
77        kmem_free( &req );
78        return NULL;
79    }
80
81    // initialize mapper type
82    mapper->type = type;
83
84    // initialize mapper lock
85    rwlock_init(  &mapper->lock );
86
87    // initialize waiting threads xlist (empty)
88    xlist_root_init( XPTR( local_cxy , &mapper->wait_root ) );
89
90    // initialize vsegs xlist (empty)
91    xlist_root_init( XPTR( local_cxy , &mapper->vsegs_root ) );
92
93    return mapper;
94
95}  // end mapper_create()
96
97///////////////////////////////////////////
98error_t mapper_destroy( mapper_t * mapper )
99{
100    page_t   * page;
101    uint32_t   found_index = 0;
102    uint32_t   start_index = 0;
103    kmem_req_t req;
104    error_t    error;
105
106    // scan radix three and release all registered pages to PPM
107    do
108    {
109        // get page from radix tree
110        page = (page_t *)grdxt_get_first( &mapper->radix , start_index , &found_index );
111
112        if( page != NULL )
113        {
114            // remove page from mapper and release to PPM
115            error = mapper_release_page( mapper , page );
116
117            if ( error ) return error;
118
119            // update start_key value for next page
120            start_index = found_index;
121        }
122    }
123    while( page != NULL );
124
125    // release the memory allocated to radix-tree itself
126    grdxt_destroy( &mapper->radix );
127
128    // release memory for mapper descriptor
129    req.type = KMEM_MAPPER;
130    req.ptr  = mapper;
131    kmem_free( &req );
132
133    return 0;
134
135}  // end mapper_destroy()
136
137////////////////////////////////////////////
138page_t * mapper_get_page( mapper_t * mapper,
139                          uint32_t   index )
140{
141    kmem_req_t    req;
142    page_t      * page;
143    error_t       error;
144
145mapper_dmsg("\n[DBG] %s : core[%x,%d] enters for page %d / mapper %x\n",
146__FUNCTION__ , local_cxy , CURRENT_THREAD->core->lid , index , mapper );
147
148    thread_t * this = CURRENT_THREAD;
149
150    // take mapper lock in READ_MODE
151    rwlock_rd_lock( &mapper->lock );
152
153    // search page in radix tree
154    page = (page_t *)grdxt_lookup( &mapper->radix , index );
155
156    // test if page available in mapper
157    if( ( page == NULL) || page_is_flag( page , PG_INLOAD ) )  // page not available
158    {
159
160        // release the lock in READ_MODE and take it in WRITE_MODE
161        rwlock_rd_unlock( &mapper->lock );
162        rwlock_wr_lock( &mapper->lock );
163
164        // second test on missing page because the page status can have been modified
165        // by another thread, when passing from READ_MODE to WRITE_MODE.
166        // from this point there is no concurrent accesses to mapper.
167
168        page = grdxt_lookup( &mapper->radix , index );
169
170        if ( page == NULL )   // missing page => create it and load it from file system
171        {
172
173mapper_dmsg("\n[DBG] %s : core[%x,%d] missing page => load from device\n",
174__FUNCTION__ , local_cxy , CURRENT_THREAD->core->lid );
175
176            // allocate one page from PPM
177            req.type  = KMEM_PAGE;
178            req.size  = 0;
179            req.flags = AF_NONE;
180            page = kmem_alloc( &req );
181
182            if( page == NULL )
183            {
184                printk("\n[ERROR] in %s : thread %x cannot allocate a page in cluster %x\n",
185                       __FUNCTION__ , this->trdid , local_cxy );
186                rwlock_wr_unlock( &mapper->lock );
187                return NULL;
188            }
189
190            // initialize the page descriptor
191            page_init( page );
192            page_set_flag( page , PG_INIT | PG_INLOAD );
193            page_refcount_up( page );
194            page->mapper = mapper;
195            page->index  = index;
196
197            // insert page in mapper radix tree
198            error = grdxt_insert( &mapper->radix, index , page );
199
200            // release mapper lock from WRITE_MODE
201            rwlock_wr_unlock( &mapper->lock );
202
203            if( error )
204            {
205                printk("\n[ERROR] in %s : thread %x cannot insert page in mapper\n",
206                       __FUNCTION__ , this->trdid );
207                mapper_release_page( mapper , page );
208                page_clear_flag( page , PG_ALL );
209                req.ptr  = page;
210                req.type = KMEM_PAGE;
211                kmem_free(&req);
212                return NULL;
213            }
214
215            // launch I/O operation to load page from file system
216            error = vfs_mapper_move_page( page, 
217                                          true );   // to mapper
218            if( error )
219            {
220                printk("\n[ERROR] in %s : thread %x cannot load page from device\n",
221                       __FUNCTION__ , this->trdid );
222                mapper_release_page( mapper , page );
223                page_clear_flag( page , PG_ALL );
224                req.ptr  = page;
225                req.type = KMEM_PAGE;
226                kmem_free( &req );
227                return NULL;
228            }
229
230            // reset the page INLOAD flag to make the page available to all readers
231            page_clear_flag( page , PG_INLOAD );
232
233mapper_dmsg("\n[DBG] %s : missing page loaded / ppn = %x\n",
234__FUNCTION__ , ppm_page2ppn(XPTR(local_cxy,page)) );
235
236        }
237        else if( page_is_flag( page , PG_INLOAD ) )   // page is loaded by another thread
238        {
239            // release mapper lock from WRITE_MODE
240            rwlock_wr_unlock( &mapper->lock );
241
242            // deschedule to wait load completion
243            while( 1 )
244            {
245                // exit waiting loop when loaded
246                if(  page_is_flag( page , PG_INLOAD ) ) break;
247
248                // deschedule
249                sched_yield();
250            }
251        }
252    }
253    else                          // page available in mapper
254    {
255
256        rwlock_rd_unlock( &mapper->lock );
257    }
258
259mapper_dmsg("\n[DBG] %s : exit for page %d / mapper %x / page_desc = %x\n",
260__FUNCTION__ , index , mapper , page );
261
262    return page;
263
264}  // end mapper_get_page()
265
266///////////////////////////////////////////////
267error_t mapper_release_page( mapper_t * mapper,
268                             page_t   * page )
269{
270    error_t error;
271
272    // lauch IO operation to update page to file system
273    error = vfs_mapper_move_page( page , false );    // from mapper
274
275    if( error )
276    {
277        printk("\n[ERROR] in %s : cannot update file system\n", __FUNCTION__ );
278        return EIO;
279    }
280
281    // take mapper lock in WRITE_MODE
282    rwlock_wr_lock( &mapper->lock );
283
284    // remove physical page from radix tree
285    grdxt_remove( &mapper->radix , page->index );
286
287    // release mapper lock from WRITE_MODE
288    rwlock_wr_unlock( &mapper->lock );
289
290    // release page to PPM
291    kmem_req_t   req;
292    req.type  = KMEM_PAGE;
293    req.ptr   = page;
294    kmem_free( &req );
295
296    return 0;
297
298}  // end mapper_release_page()
299
300///////////////////////////////////////////////////
301error_t mapper_move_user( mapper_t * mapper,
302                          bool_t     to_buffer,
303                          uint32_t   file_offset,
304                          void     * buffer,
305                          uint32_t   size )
306{
307    uint32_t   page_offset;    // first byte to move to/from a mapper page
308    uint32_t   page_count;     // number of bytes to move to/from a mapper page
309    uint32_t   index;          // current mapper page index
310    uint32_t   done;           // number of moved bytes
311    page_t   * page;           // current mapper page descriptor
312    uint8_t  * map_ptr;        // current mapper  address
313    uint8_t  * buf_ptr;        // current buffer  address
314
315    mapper_dmsg("\n[DBG] %s : enters / to_buf = %d / buffer = %x\n",
316                __FUNCTION__ , to_buffer , buffer );
317
318    // compute offsets of first and last bytes in file
319    uint32_t min_byte = file_offset;
320    uint32_t max_byte = file_offset + size -1;
321
322    // compute indexes of pages for first and last byte in mapper
323    uint32_t first = min_byte >> CONFIG_PPM_PAGE_SHIFT;
324    uint32_t last  = max_byte >> CONFIG_PPM_PAGE_SHIFT;
325
326    done = 0;
327
328    // loop on pages in mapper
329    for( index = first ; index <= last ; index++ )
330    {
331        // compute page_offset
332        if( index == first ) page_offset = min_byte & CONFIG_PPM_PAGE_MASK;
333        else                 page_offset = 0;
334
335        // compute number of bytes in page
336        if      ( first == last  ) page_count = size;
337        else if ( index == first ) page_count = CONFIG_PPM_PAGE_SIZE - page_offset;
338        else if ( index == last  ) page_count = (max_byte & CONFIG_PPM_PAGE_MASK) + 1;
339        else                       page_count = CONFIG_PPM_PAGE_SIZE;
340
341        mapper_dmsg("\n[DBG] %s : index = %d / offset = %d / count = %d\n",
342                    __FUNCTION__ , index , page_offset , page_count );
343
344        // get page descriptor
345        page = mapper_get_page( mapper , index );
346
347        if ( page == NULL ) return EINVAL;
348
349        // compute pointer in mapper
350        xptr_t base_xp = ppm_page2base( XPTR( local_cxy, page ) );
351        map_ptr = (uint8_t *)GET_PTR( base_xp ) + page_offset;
352
353        // compute pointer in buffer
354        buf_ptr = (uint8_t *)buffer + done;
355
356        mapper_dmsg("\n[DBG] %s : index = %d / buf_ptr = %x / map_ptr = %x\n",
357                    __FUNCTION__ , index , buf_ptr , map_ptr );
358
359        // move fragment
360        if( to_buffer )
361        {
362            hal_copy_to_uspace( buf_ptr , map_ptr , page_count );
363        }
364        else
365        {
366            page_do_dirty( page );
367            hal_copy_from_uspace( map_ptr , buf_ptr , page_count );
368        }
369
370        done += page_count;
371    }
372
373    mapper_dmsg("\n[DBG] %s : exit for buffer %x\n",
374                __FUNCTION__, buffer );
375
376    return 0;
377
378}  // end mapper_move_user()
379
380////////////////////////////////////////////////
381error_t mapper_move_kernel( mapper_t  *  mapper,
382                            bool_t       to_buffer,
383                            uint32_t     file_offset,
384                            xptr_t       buffer_xp,
385                            uint32_t     size )
386{
387    uint32_t   page_offset;    // first byte to move to/from a mapper page
388    uint32_t   page_count;     // number of bytes to move to/from a mapper page
389    uint32_t   index;          // current mapper page index
390    uint32_t   done;           // number of moved bytes
391    page_t   * page;           // current mapper page descriptor
392
393    uint8_t  * src_ptr;        // source buffer local pointer
394    cxy_t      src_cxy;        // source cluster
395    uint8_t  * dst_ptr;        // destination buffer local pointer
396    cxy_t      dst_cxy;        // destination cluster
397
398    // get buffer cluster and local pointer
399    cxy_t     buffer_cxy = GET_CXY( buffer_xp );
400    uint8_t * buffer_ptr = (uint8_t *)GET_PTR( buffer_xp );
401
402mapper_dmsg("\n[DBG] %s : core[%x,%d] / to_buf = %d / buf_cxy = %x / buf_ptr = %x / size = %x\n",
403__FUNCTION__, local_cxy, CURRENT_THREAD->core->lid, to_buffer, buffer_cxy, buffer_ptr, size );
404
405    // compute offsets of first and last bytes in file
406    uint32_t min_byte = file_offset;
407    uint32_t max_byte = file_offset + size -1;
408
409    // compute indexes for first and last pages in mapper
410    uint32_t first = min_byte >> CONFIG_PPM_PAGE_SHIFT;
411    uint32_t last  = max_byte >> CONFIG_PPM_PAGE_SHIFT;
412
413mapper_dmsg("\n[DBG] %s : core[%x,%d] / first_page = %d / last_page = %d\n",
414__FUNCTION__, local_cxy, CURRENT_THREAD->core->lid, first, last );
415
416    // compute source and destination clusters
417    if( to_buffer )
418    {
419        dst_cxy = buffer_cxy;
420        src_cxy = local_cxy;
421    }
422    else
423    {
424        src_cxy = buffer_cxy;
425        dst_cxy = local_cxy;
426    }
427
428    done = 0;
429
430    // loop on pages in mapper
431    for( index = first ; index <= last ; index++ )
432    {
433        // compute page_offset
434        if( index == first ) page_offset = min_byte & CONFIG_PPM_PAGE_MASK;
435        else                 page_offset = 0;
436
437        // compute number of bytes to move in page
438        if      ( first == last  ) page_count = size;
439        else if ( index == first ) page_count = CONFIG_PPM_PAGE_SIZE - page_offset;
440        else if ( index == last  ) page_count = (max_byte & CONFIG_PPM_PAGE_MASK) + 1;
441        else                       page_count = CONFIG_PPM_PAGE_SIZE;
442
443mapper_dmsg("\n[DBG] %s : core[%x;%d] / page_index = %d / offset = %d / bytes = %d\n",
444__FUNCTION__ , local_cxy, CURRENT_THREAD->core->lid, index, page_offset, page_count );
445
446        // get page descriptor
447        page = mapper_get_page( mapper , index );
448
449        if ( page == NULL ) return EINVAL;
450
451        // get page base address
452        xptr_t    base_xp  = ppm_page2base( XPTR( local_cxy , page ) );
453        uint8_t * base_ptr = (uint8_t *)GET_PTR( base_xp );
454
455        // compute source and destination pointers
456        if( to_buffer )
457        {
458            dst_ptr = buffer_ptr + done;
459            src_ptr = base_ptr + page_offset;
460        }
461        else
462        {
463            src_ptr = buffer_ptr + done;
464            dst_ptr = base_ptr + page_offset;
465
466            page_do_dirty( page );
467        }
468
469        // move fragment
470        hal_remote_memcpy( XPTR( dst_cxy , dst_ptr ), XPTR( src_cxy , src_ptr ), page_count );
471
472        done += page_count;
473    }
474
475mapper_dmsg("\n[DBG] %s : core_cxy[%x,%d] / exit / buf_cxy = %x / buf_ptr = %x / size = %x\n",
476__FUNCTION__, local_cxy, CURRENT_THREAD->core->lid, buffer_cxy, buffer_ptr, size );
477
478    return 0;
479
480}  // end mapper_move_kernel()
481
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