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1
/*
1
/*
2
 * Copyright (c) 2008 Jakub Jermar
2
 * Copyright (c) 2008 Jakub Jermar
3
 * All rights reserved.
3
 * All rights reserved.
4
 *
4
 *
5
 * Redistribution and use in source and binary forms, with or without
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
6
 * modification, are permitted provided that the following conditions
7
 * are met:
7
 * are met:
8
 *
8
 *
9
 * - Redistributions of source code must retain the above copyright
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
15
 *   derived from this software without specific prior written permission.
16
 *
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
27
 */
28
 
28
 
29
/** @addtogroup fs
29
/** @addtogroup fs
30
 * @{
30
 * @{
31
 */
31
 */
32
 
32
 
33
/**
33
/**
34
 * @file    fat_ops.c
34
 * @file    fat_ops.c
35
 * @brief   Implementation of VFS operations for the FAT file system server.
35
 * @brief   Implementation of VFS operations for the FAT file system server.
36
 */
36
 */
37
 
37
 
38
#include "fat.h"
38
#include "fat.h"
39
#include "fat_dentry.h"
39
#include "fat_dentry.h"
40
#include "fat_fat.h"
40
#include "fat_fat.h"
41
#include "../../vfs/vfs.h"
41
#include "../../vfs/vfs.h"
42
#include <libfs.h>
42
#include <libfs.h>
43
#include <ipc/ipc.h>
43
#include <ipc/ipc.h>
44
#include <ipc/services.h>
44
#include <ipc/services.h>
45
#include <ipc/devmap.h>
45
#include <ipc/devmap.h>
46
#include <async.h>
46
#include <async.h>
47
#include <errno.h>
47
#include <errno.h>
48
#include <string.h>
48
#include <string.h>
49
#include <byteorder.h>
49
#include <byteorder.h>
50
#include <libadt/hash_table.h>
50
#include <libadt/hash_table.h>
51
#include <libadt/list.h>
51
#include <libadt/list.h>
52
#include <assert.h>
52
#include <assert.h>
53
#include <futex.h>
53
#include <futex.h>
54
#include <sys/mman.h>
54
#include <sys/mman.h>
55
#include <align.h>
55
#include <align.h>
56
 
56
 
57
/** Futex protecting the list of cached free FAT nodes. */
57
/** Futex protecting the list of cached free FAT nodes. */
58
static futex_t ffn_futex = FUTEX_INITIALIZER;
58
static futex_t ffn_futex = FUTEX_INITIALIZER;
59
 
59
 
60
/** List of cached free FAT nodes. */
60
/** List of cached free FAT nodes. */
61
static LIST_INITIALIZE(ffn_head);
61
static LIST_INITIALIZE(ffn_head);
62
 
62
 
63
static int dev_phone = -1;      /* FIXME */
63
static int dev_phone = -1;      /* FIXME */
64
static void *dev_buffer = NULL;     /* FIXME */
64
static void *dev_buffer = NULL;     /* FIXME */
65
 
65
 
66
block_t *block_get(dev_handle_t dev_handle, off_t offset, size_t bs)
66
block_t *block_get(dev_handle_t dev_handle, off_t offset, size_t bs)
67
{
67
{
68
    /* FIXME */
68
    /* FIXME */
69
    block_t *b;
69
    block_t *b;
70
    off_t bufpos = 0;
70
    off_t bufpos = 0;
71
    size_t buflen = 0;
71
    size_t buflen = 0;
72
    off_t pos = offset * bs;
72
    off_t pos = offset * bs;
73
 
73
 
74
    assert(dev_phone != -1);
74
    assert(dev_phone != -1);
75
    assert(dev_buffer);
75
    assert(dev_buffer);
76
 
76
 
77
    b = malloc(sizeof(block_t));
77
    b = malloc(sizeof(block_t));
78
    if (!b)
78
    if (!b)
79
        return NULL;
79
        return NULL;
80
   
80
   
81
    b->data = malloc(bs);
81
    b->data = malloc(bs);
82
    if (!b->data) {
82
    if (!b->data) {
83
        free(b);
83
        free(b);
84
        return NULL;
84
        return NULL;
85
    }
85
    }
86
    b->size = bs;
86
    b->size = bs;
87
 
87
 
88
    if (!libfs_blockread(dev_phone, dev_buffer, &bufpos, &buflen, &pos,
88
    if (!libfs_blockread(dev_phone, dev_buffer, &bufpos, &buflen, &pos,
89
        b->data, bs, bs)) {
89
        b->data, bs, bs)) {
90
        free(b->data);
90
        free(b->data);
91
        free(b);
91
        free(b);
92
        return NULL;
92
        return NULL;
93
    }
93
    }
94
 
94
 
95
    return b;
95
    return b;
96
}
96
}
97
 
97
 
98
void block_put(block_t *block)
98
void block_put(block_t *block)
99
{
99
{
100
    /* FIXME */
100
    /* FIXME */
101
    free(block->data);
101
    free(block->data);
102
    free(block);
102
    free(block);
103
}
103
}
104
 
104
 
105
static void fat_node_initialize(fat_node_t *node)
105
static void fat_node_initialize(fat_node_t *node)
106
{
106
{
107
    futex_initialize(&node->lock, 1);
107
    futex_initialize(&node->lock, 1);
108
    node->idx = NULL;
108
    node->idx = NULL;
109
    node->type = 0;
109
    node->type = 0;
110
    link_initialize(&node->ffn_link);
110
    link_initialize(&node->ffn_link);
111
    node->size = 0;
111
    node->size = 0;
112
    node->lnkcnt = 0;
112
    node->lnkcnt = 0;
113
    node->refcnt = 0;
113
    node->refcnt = 0;
114
    node->dirty = false;
114
    node->dirty = false;
115
}
115
}
116
 
116
 
117
static void fat_node_sync(fat_node_t *node)
117
static void fat_node_sync(fat_node_t *node)
118
{
118
{
119
    /* TODO */
119
    /* TODO */
120
}
120
}
121
 
121
 
122
/** Internal version of fat_node_get().
122
/** Internal version of fat_node_get().
123
 *
123
 *
124
 * @param idxp      Locked index structure.
124
 * @param idxp      Locked index structure.
125
 */
125
 */
126
static void *fat_node_get_core(fat_idx_t *idxp)
126
static void *fat_node_get_core(fat_idx_t *idxp)
127
{
127
{
128
    block_t *b;
128
    block_t *b;
129
    fat_dentry_t *d;
129
    fat_dentry_t *d;
130
    fat_node_t *nodep = NULL;
130
    fat_node_t *nodep = NULL;
131
    unsigned bps;
131
    unsigned bps;
132
    unsigned dps;
132
    unsigned dps;
133
 
133
 
134
    if (idxp->nodep) {
134
    if (idxp->nodep) {
135
        /*
135
        /*
136
         * We are lucky.
136
         * We are lucky.
137
         * The node is already instantiated in memory.
137
         * The node is already instantiated in memory.
138
         */
138
         */
139
        futex_down(&idxp->nodep->lock);
139
        futex_down(&idxp->nodep->lock);
140
        if (!idxp->nodep->refcnt++)
140
        if (!idxp->nodep->refcnt++)
141
            list_remove(&idxp->nodep->ffn_link);
141
            list_remove(&idxp->nodep->ffn_link);
142
        futex_up(&idxp->nodep->lock);
142
        futex_up(&idxp->nodep->lock);
143
        return idxp->nodep;
143
        return idxp->nodep;
144
    }
144
    }
145
 
145
 
146
    /*
146
    /*
147
     * We must instantiate the node from the file system.
147
     * We must instantiate the node from the file system.
148
     */
148
     */
149
   
149
   
150
    assert(idxp->pfc);
150
    assert(idxp->pfc);
151
 
151
 
152
    futex_down(&ffn_futex);
152
    futex_down(&ffn_futex);
153
    if (!list_empty(&ffn_head)) {
153
    if (!list_empty(&ffn_head)) {
154
        /* Try to use a cached free node structure. */
154
        /* Try to use a cached free node structure. */
155
        fat_idx_t *idxp_tmp;
155
        fat_idx_t *idxp_tmp;
156
        nodep = list_get_instance(ffn_head.next, fat_node_t, ffn_link);
156
        nodep = list_get_instance(ffn_head.next, fat_node_t, ffn_link);
157
        if (futex_trydown(&nodep->lock) == ESYNCH_WOULD_BLOCK)
157
        if (futex_trydown(&nodep->lock) == ESYNCH_WOULD_BLOCK)
158
            goto skip_cache;
158
            goto skip_cache;
159
        idxp_tmp = nodep->idx;
159
        idxp_tmp = nodep->idx;
160
        if (futex_trydown(&idxp_tmp->lock) == ESYNCH_WOULD_BLOCK) {
160
        if (futex_trydown(&idxp_tmp->lock) == ESYNCH_WOULD_BLOCK) {
161
            futex_up(&nodep->lock);
161
            futex_up(&nodep->lock);
162
            goto skip_cache;
162
            goto skip_cache;
163
        }
163
        }
164
        list_remove(&nodep->ffn_link);
164
        list_remove(&nodep->ffn_link);
165
        futex_up(&ffn_futex);
165
        futex_up(&ffn_futex);
166
        if (nodep->dirty)
166
        if (nodep->dirty)
167
            fat_node_sync(nodep);
167
            fat_node_sync(nodep);
168
        idxp_tmp->nodep = NULL;
168
        idxp_tmp->nodep = NULL;
169
        futex_up(&nodep->lock);
169
        futex_up(&nodep->lock);
170
        futex_up(&idxp_tmp->lock);
170
        futex_up(&idxp_tmp->lock);
171
    } else {
171
    } else {
172
skip_cache:
172
skip_cache:
173
        /* Try to allocate a new node structure. */
173
        /* Try to allocate a new node structure. */
174
        futex_up(&ffn_futex);
174
        futex_up(&ffn_futex);
175
        nodep = (fat_node_t *)malloc(sizeof(fat_node_t));
175
        nodep = (fat_node_t *)malloc(sizeof(fat_node_t));
176
        if (!nodep)
176
        if (!nodep)
177
            return NULL;
177
            return NULL;
178
    }
178
    }
179
    fat_node_initialize(nodep);
179
    fat_node_initialize(nodep);
180
 
180
 
181
    bps = fat_bps_get(idxp->dev_handle);
181
    bps = fat_bps_get(idxp->dev_handle);
182
    dps = bps / sizeof(fat_dentry_t);
182
    dps = bps / sizeof(fat_dentry_t);
183
 
183
 
184
    /* Read the block that contains the dentry of interest. */
184
    /* Read the block that contains the dentry of interest. */
185
    b = _fat_block_get(idxp->dev_handle, idxp->pfc,
185
    b = _fat_block_get(idxp->dev_handle, idxp->pfc,
186
        (idxp->pdi * sizeof(fat_dentry_t)) / bps);
186
        (idxp->pdi * sizeof(fat_dentry_t)) / bps);
187
    assert(b);
187
    assert(b);
188
 
188
 
189
    d = ((fat_dentry_t *)b->data) + (idxp->pdi % dps);
189
    d = ((fat_dentry_t *)b->data) + (idxp->pdi % dps);
190
    if (d->attr & FAT_ATTR_SUBDIR) {
190
    if (d->attr & FAT_ATTR_SUBDIR) {
191
        /*
191
        /*
192
         * The only directory which does not have this bit set is the
192
         * The only directory which does not have this bit set is the
193
         * root directory itself. The root directory node is handled
193
         * root directory itself. The root directory node is handled
194
         * and initialized elsewhere.
194
         * and initialized elsewhere.
195
         */
195
         */
196
        nodep->type = FAT_DIRECTORY;
196
        nodep->type = FAT_DIRECTORY;
197
        /*
197
        /*
198
         * Unfortunately, the 'size' field of the FAT dentry is not
198
         * Unfortunately, the 'size' field of the FAT dentry is not
199
         * defined for the directory entry type. We must determine the
199
         * defined for the directory entry type. We must determine the
200
         * size of the directory by walking the FAT.
200
         * size of the directory by walking the FAT.
201
         */
201
         */
202
        nodep->size = bps * _fat_blcks_get(idxp->dev_handle,
202
        nodep->size = bps * _fat_blcks_get(idxp->dev_handle,
203
            uint16_t_le2host(d->firstc));
203
            uint16_t_le2host(d->firstc), NULL);
204
    } else {
204
    } else {
205
        nodep->type = FAT_FILE;
205
        nodep->type = FAT_FILE;
206
        nodep->size = uint32_t_le2host(d->size);
206
        nodep->size = uint32_t_le2host(d->size);
207
    }
207
    }
208
    nodep->firstc = uint16_t_le2host(d->firstc);
208
    nodep->firstc = uint16_t_le2host(d->firstc);
209
    nodep->lnkcnt = 1;
209
    nodep->lnkcnt = 1;
210
    nodep->refcnt = 1;
210
    nodep->refcnt = 1;
211
 
211
 
212
    block_put(b);
212
    block_put(b);
213
 
213
 
214
    /* Link the idx structure with the node structure. */
214
    /* Link the idx structure with the node structure. */
215
    nodep->idx = idxp;
215
    nodep->idx = idxp;
216
    idxp->nodep = nodep;
216
    idxp->nodep = nodep;
217
 
217
 
218
    return nodep;
218
    return nodep;
219
}
219
}
220
 
220
 
221
/** Instantiate a FAT in-core node. */
221
/** Instantiate a FAT in-core node. */
222
static void *fat_node_get(dev_handle_t dev_handle, fs_index_t index)
222
static void *fat_node_get(dev_handle_t dev_handle, fs_index_t index)
223
{
223
{
224
    void *node;
224
    void *node;
225
    fat_idx_t *idxp;
225
    fat_idx_t *idxp;
226
 
226
 
227
    idxp = fat_idx_get_by_index(dev_handle, index);
227
    idxp = fat_idx_get_by_index(dev_handle, index);
228
    if (!idxp)
228
    if (!idxp)
229
        return NULL;
229
        return NULL;
230
    /* idxp->lock held */
230
    /* idxp->lock held */
231
    node = fat_node_get_core(idxp);
231
    node = fat_node_get_core(idxp);
232
    futex_up(&idxp->lock);
232
    futex_up(&idxp->lock);
233
    return node;
233
    return node;
234
}
234
}
235
 
235
 
236
static void fat_node_put(void *node)
236
static void fat_node_put(void *node)
237
{
237
{
238
    fat_node_t *nodep = (fat_node_t *)node;
238
    fat_node_t *nodep = (fat_node_t *)node;
239
 
239
 
240
    futex_down(&nodep->lock);
240
    futex_down(&nodep->lock);
241
    if (!--nodep->refcnt) {
241
    if (!--nodep->refcnt) {
242
        futex_down(&ffn_futex);
242
        futex_down(&ffn_futex);
243
        list_append(&nodep->ffn_link, &ffn_head);
243
        list_append(&nodep->ffn_link, &ffn_head);
244
        futex_up(&ffn_futex);
244
        futex_up(&ffn_futex);
245
    }
245
    }
246
    futex_up(&nodep->lock);
246
    futex_up(&nodep->lock);
247
}
247
}
248
 
248
 
249
static void *fat_create(int flags)
249
static void *fat_create(int flags)
250
{
250
{
251
    return NULL;    /* not supported at the moment */
251
    return NULL;    /* not supported at the moment */
252
}
252
}
253
 
253
 
254
static int fat_destroy(void *node)
254
static int fat_destroy(void *node)
255
{
255
{
256
    return ENOTSUP; /* not supported at the moment */
256
    return ENOTSUP; /* not supported at the moment */
257
}
257
}
258
 
258
 
259
static bool fat_link(void *prnt, void *chld, const char *name)
259
static bool fat_link(void *prnt, void *chld, const char *name)
260
{
260
{
261
    return false;   /* not supported at the moment */
261
    return false;   /* not supported at the moment */
262
}
262
}
263
 
263
 
264
static int fat_unlink(void *prnt, void *chld)
264
static int fat_unlink(void *prnt, void *chld)
265
{
265
{
266
    return ENOTSUP; /* not supported at the moment */
266
    return ENOTSUP; /* not supported at the moment */
267
}
267
}
268
 
268
 
269
static void *fat_match(void *prnt, const char *component)
269
static void *fat_match(void *prnt, const char *component)
270
{
270
{
271
    fat_node_t *parentp = (fat_node_t *)prnt;
271
    fat_node_t *parentp = (fat_node_t *)prnt;
272
    char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1];
272
    char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1];
273
    unsigned i, j;
273
    unsigned i, j;
274
    unsigned bps;       /* bytes per sector */
274
    unsigned bps;       /* bytes per sector */
275
    unsigned dps;       /* dentries per sector */
275
    unsigned dps;       /* dentries per sector */
276
    unsigned blocks;
276
    unsigned blocks;
277
    fat_dentry_t *d;
277
    fat_dentry_t *d;
278
    block_t *b;
278
    block_t *b;
279
 
279
 
280
    futex_down(&parentp->idx->lock);
280
    futex_down(&parentp->idx->lock);
281
    bps = fat_bps_get(parentp->idx->dev_handle);
281
    bps = fat_bps_get(parentp->idx->dev_handle);
282
    dps = bps / sizeof(fat_dentry_t);
282
    dps = bps / sizeof(fat_dentry_t);
283
    blocks = parentp->size / bps + (parentp->size % bps != 0);
283
    blocks = parentp->size / bps + (parentp->size % bps != 0);
284
    for (i = 0; i < blocks; i++) {
284
    for (i = 0; i < blocks; i++) {
285
        unsigned dentries;
285
        unsigned dentries;
286
       
286
       
287
        b = fat_block_get(parentp, i);
287
        b = fat_block_get(parentp, i);
288
        dentries = (i == blocks - 1) ?
288
        dentries = (i == blocks - 1) ?
289
            parentp->size % sizeof(fat_dentry_t) :
289
            parentp->size % sizeof(fat_dentry_t) :
290
            dps;
290
            dps;
291
        for (j = 0; j < dentries; j++) {
291
        for (j = 0; j < dentries; j++) {
292
            d = ((fat_dentry_t *)b->data) + j;
292
            d = ((fat_dentry_t *)b->data) + j;
293
            switch (fat_classify_dentry(d)) {
293
            switch (fat_classify_dentry(d)) {
294
            case FAT_DENTRY_SKIP:
294
            case FAT_DENTRY_SKIP:
295
                continue;
295
                continue;
296
            case FAT_DENTRY_LAST:
296
            case FAT_DENTRY_LAST:
297
                block_put(b);
297
                block_put(b);
298
                futex_up(&parentp->idx->lock);
298
                futex_up(&parentp->idx->lock);
299
                return NULL;
299
                return NULL;
300
            default:
300
            default:
301
            case FAT_DENTRY_VALID:
301
            case FAT_DENTRY_VALID:
302
                dentry_name_canonify(d, name);
302
                dentry_name_canonify(d, name);
303
                break;
303
                break;
304
            }
304
            }
305
            if (stricmp(name, component) == 0) {
305
            if (stricmp(name, component) == 0) {
306
                /* hit */
306
                /* hit */
307
                void *node;
307
                void *node;
308
                /*
308
                /*
309
                 * Assume tree hierarchy for locking.  We
309
                 * Assume tree hierarchy for locking.  We
310
                 * already have the parent and now we are going
310
                 * already have the parent and now we are going
311
                 * to lock the child.  Never lock in the oposite
311
                 * to lock the child.  Never lock in the oposite
312
                 * order.
312
                 * order.
313
                 */
313
                 */
314
                fat_idx_t *idx = fat_idx_get_by_pos(
314
                fat_idx_t *idx = fat_idx_get_by_pos(
315
                    parentp->idx->dev_handle, parentp->firstc,
315
                    parentp->idx->dev_handle, parentp->firstc,
316
                    i * dps + j);
316
                    i * dps + j);
317
                futex_up(&parentp->idx->lock);
317
                futex_up(&parentp->idx->lock);
318
                if (!idx) {
318
                if (!idx) {
319
                    /*
319
                    /*
320
                     * Can happen if memory is low or if we
320
                     * Can happen if memory is low or if we
321
                     * run out of 32-bit indices.
321
                     * run out of 32-bit indices.
322
                     */
322
                     */
323
                    block_put(b);
323
                    block_put(b);
324
                    return NULL;
324
                    return NULL;
325
                }
325
                }
326
                node = fat_node_get_core(idx);
326
                node = fat_node_get_core(idx);
327
                futex_up(&idx->lock);
327
                futex_up(&idx->lock);
328
                block_put(b);
328
                block_put(b);
329
                return node;
329
                return node;
330
            }
330
            }
331
        }
331
        }
332
        block_put(b);
332
        block_put(b);
333
    }
333
    }
334
    futex_up(&parentp->idx->lock);
334
    futex_up(&parentp->idx->lock);
335
    return NULL;
335
    return NULL;
336
}
336
}
337
 
337
 
338
static fs_index_t fat_index_get(void *node)
338
static fs_index_t fat_index_get(void *node)
339
{
339
{
340
    fat_node_t *fnodep = (fat_node_t *)node;
340
    fat_node_t *fnodep = (fat_node_t *)node;
341
    if (!fnodep)
341
    if (!fnodep)
342
        return 0;
342
        return 0;
343
    return fnodep->idx->index;
343
    return fnodep->idx->index;
344
}
344
}
345
 
345
 
346
static size_t fat_size_get(void *node)
346
static size_t fat_size_get(void *node)
347
{
347
{
348
    return ((fat_node_t *)node)->size;
348
    return ((fat_node_t *)node)->size;
349
}
349
}
350
 
350
 
351
static unsigned fat_lnkcnt_get(void *node)
351
static unsigned fat_lnkcnt_get(void *node)
352
{
352
{
353
    return ((fat_node_t *)node)->lnkcnt;
353
    return ((fat_node_t *)node)->lnkcnt;
354
}
354
}
355
 
355
 
356
static bool fat_has_children(void *node)
356
static bool fat_has_children(void *node)
357
{
357
{
358
    fat_node_t *nodep = (fat_node_t *)node;
358
    fat_node_t *nodep = (fat_node_t *)node;
359
    unsigned bps;
359
    unsigned bps;
360
    unsigned dps;
360
    unsigned dps;
361
    unsigned blocks;
361
    unsigned blocks;
362
    block_t *b;
362
    block_t *b;
363
    unsigned i, j;
363
    unsigned i, j;
364
 
364
 
365
    if (nodep->type != FAT_DIRECTORY)
365
    if (nodep->type != FAT_DIRECTORY)
366
        return false;
366
        return false;
367
 
367
 
368
    futex_down(&nodep->idx->lock);
368
    futex_down(&nodep->idx->lock);
369
    bps = fat_bps_get(nodep->idx->dev_handle);
369
    bps = fat_bps_get(nodep->idx->dev_handle);
370
    dps = bps / sizeof(fat_dentry_t);
370
    dps = bps / sizeof(fat_dentry_t);
371
 
371
 
372
    blocks = nodep->size / bps + (nodep->size % bps != 0);
372
    blocks = nodep->size / bps + (nodep->size % bps != 0);
373
 
373
 
374
    for (i = 0; i < blocks; i++) {
374
    for (i = 0; i < blocks; i++) {
375
        unsigned dentries;
375
        unsigned dentries;
376
        fat_dentry_t *d;
376
        fat_dentry_t *d;
377
   
377
   
378
        b = fat_block_get(nodep, i);
378
        b = fat_block_get(nodep, i);
379
        dentries = (i == blocks - 1) ?
379
        dentries = (i == blocks - 1) ?
380
            nodep->size % sizeof(fat_dentry_t) :
380
            nodep->size % sizeof(fat_dentry_t) :
381
            dps;
381
            dps;
382
        for (j = 0; j < dentries; j++) {
382
        for (j = 0; j < dentries; j++) {
383
            d = ((fat_dentry_t *)b->data) + j;
383
            d = ((fat_dentry_t *)b->data) + j;
384
            switch (fat_classify_dentry(d)) {
384
            switch (fat_classify_dentry(d)) {
385
            case FAT_DENTRY_SKIP:
385
            case FAT_DENTRY_SKIP:
386
                continue;
386
                continue;
387
            case FAT_DENTRY_LAST:
387
            case FAT_DENTRY_LAST:
388
                block_put(b);
388
                block_put(b);
389
                futex_up(&nodep->idx->lock);
389
                futex_up(&nodep->idx->lock);
390
                return false;
390
                return false;
391
            default:
391
            default:
392
            case FAT_DENTRY_VALID:
392
            case FAT_DENTRY_VALID:
393
                block_put(b);
393
                block_put(b);
394
                futex_up(&nodep->idx->lock);
394
                futex_up(&nodep->idx->lock);
395
                return true;
395
                return true;
396
            }
396
            }
397
            block_put(b);
397
            block_put(b);
398
            futex_up(&nodep->idx->lock);
398
            futex_up(&nodep->idx->lock);
399
            return true;
399
            return true;
400
        }
400
        }
401
        block_put(b);
401
        block_put(b);
402
    }
402
    }
403
 
403
 
404
    futex_up(&nodep->idx->lock);
404
    futex_up(&nodep->idx->lock);
405
    return false;
405
    return false;
406
}
406
}
407
 
407
 
408
static void *fat_root_get(dev_handle_t dev_handle)
408
static void *fat_root_get(dev_handle_t dev_handle)
409
{
409
{
410
    return fat_node_get(dev_handle, 0);
410
    return fat_node_get(dev_handle, 0);
411
}
411
}
412
 
412
 
413
static char fat_plb_get_char(unsigned pos)
413
static char fat_plb_get_char(unsigned pos)
414
{
414
{
415
    return fat_reg.plb_ro[pos % PLB_SIZE];
415
    return fat_reg.plb_ro[pos % PLB_SIZE];
416
}
416
}
417
 
417
 
418
static bool fat_is_directory(void *node)
418
static bool fat_is_directory(void *node)
419
{
419
{
420
    return ((fat_node_t *)node)->type == FAT_DIRECTORY;
420
    return ((fat_node_t *)node)->type == FAT_DIRECTORY;
421
}
421
}
422
 
422
 
423
static bool fat_is_file(void *node)
423
static bool fat_is_file(void *node)
424
{
424
{
425
    return ((fat_node_t *)node)->type == FAT_FILE;
425
    return ((fat_node_t *)node)->type == FAT_FILE;
426
}
426
}
427
 
427
 
428
/** libfs operations */
428
/** libfs operations */
429
libfs_ops_t fat_libfs_ops = {
429
libfs_ops_t fat_libfs_ops = {
430
    .match = fat_match,
430
    .match = fat_match,
431
    .node_get = fat_node_get,
431
    .node_get = fat_node_get,
432
    .node_put = fat_node_put,
432
    .node_put = fat_node_put,
433
    .create = fat_create,
433
    .create = fat_create,
434
    .destroy = fat_destroy,
434
    .destroy = fat_destroy,
435
    .link = fat_link,
435
    .link = fat_link,
436
    .unlink = fat_unlink,
436
    .unlink = fat_unlink,
437
    .index_get = fat_index_get,
437
    .index_get = fat_index_get,
438
    .size_get = fat_size_get,
438
    .size_get = fat_size_get,
439
    .lnkcnt_get = fat_lnkcnt_get,
439
    .lnkcnt_get = fat_lnkcnt_get,
440
    .has_children = fat_has_children,
440
    .has_children = fat_has_children,
441
    .root_get = fat_root_get,
441
    .root_get = fat_root_get,
442
    .plb_get_char = fat_plb_get_char,
442
    .plb_get_char = fat_plb_get_char,
443
    .is_directory = fat_is_directory,
443
    .is_directory = fat_is_directory,
444
    .is_file = fat_is_file
444
    .is_file = fat_is_file
445
};
445
};
446
 
446
 
447
void fat_mounted(ipc_callid_t rid, ipc_call_t *request)
447
void fat_mounted(ipc_callid_t rid, ipc_call_t *request)
448
{
448
{
449
    dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
449
    dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
450
    block_t *bb;
450
    block_t *bb;
451
    uint16_t bps;
451
    uint16_t bps;
452
    uint16_t rde;
452
    uint16_t rde;
453
    int rc;
453
    int rc;
454
 
454
 
455
    /*
455
    /*
456
     * For now, we don't bother to remember dev_handle, dev_phone or
456
     * For now, we don't bother to remember dev_handle, dev_phone or
457
     * dev_buffer in some data structure. We use global variables because we
457
     * dev_buffer in some data structure. We use global variables because we
458
     * know there will be at most one mount on this file system.
458
     * know there will be at most one mount on this file system.
459
     * Of course, this is a huge TODO item.
459
     * Of course, this is a huge TODO item.
460
     */
460
     */
461
    dev_buffer = mmap(NULL, BS_SIZE, PROTO_READ | PROTO_WRITE,
461
    dev_buffer = mmap(NULL, BS_SIZE, PROTO_READ | PROTO_WRITE,
462
        MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
462
        MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
463
   
463
   
464
    if (!dev_buffer) {
464
    if (!dev_buffer) {
465
        ipc_answer_0(rid, ENOMEM);
465
        ipc_answer_0(rid, ENOMEM);
466
        return;
466
        return;
467
    }
467
    }
468
 
468
 
469
    dev_phone = ipc_connect_me_to(PHONE_NS, SERVICE_DEVMAP,
469
    dev_phone = ipc_connect_me_to(PHONE_NS, SERVICE_DEVMAP,
470
        DEVMAP_CONNECT_TO_DEVICE, dev_handle);
470
        DEVMAP_CONNECT_TO_DEVICE, dev_handle);
471
 
471
 
472
    if (dev_phone < 0) {
472
    if (dev_phone < 0) {
473
        munmap(dev_buffer, BS_SIZE);
473
        munmap(dev_buffer, BS_SIZE);
474
        ipc_answer_0(rid, dev_phone);
474
        ipc_answer_0(rid, dev_phone);
475
        return;
475
        return;
476
    }
476
    }
477
 
477
 
478
    rc = ipc_share_out_start(dev_phone, dev_buffer,
478
    rc = ipc_share_out_start(dev_phone, dev_buffer,
479
        AS_AREA_READ | AS_AREA_WRITE);
479
        AS_AREA_READ | AS_AREA_WRITE);
480
    if (rc != EOK) {
480
    if (rc != EOK) {
481
            munmap(dev_buffer, BS_SIZE);
481
            munmap(dev_buffer, BS_SIZE);
482
        ipc_answer_0(rid, rc);
482
        ipc_answer_0(rid, rc);
483
        return;
483
        return;
484
    }
484
    }
485
 
485
 
486
    /* Read the number of root directory entries. */
486
    /* Read the number of root directory entries. */
487
    bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
487
    bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
488
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
488
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
489
    rde = uint16_t_le2host(FAT_BS(bb)->root_ent_max);
489
    rde = uint16_t_le2host(FAT_BS(bb)->root_ent_max);
490
    block_put(bb);
490
    block_put(bb);
491
 
491
 
492
    if (bps != BS_SIZE) {
492
    if (bps != BS_SIZE) {
493
        munmap(dev_buffer, BS_SIZE);
493
        munmap(dev_buffer, BS_SIZE);
494
        ipc_answer_0(rid, ENOTSUP);
494
        ipc_answer_0(rid, ENOTSUP);
495
        return;
495
        return;
496
    }
496
    }
497
 
497
 
498
    rc = fat_idx_init_by_dev_handle(dev_handle);
498
    rc = fat_idx_init_by_dev_handle(dev_handle);
499
    if (rc != EOK) {
499
    if (rc != EOK) {
500
            munmap(dev_buffer, BS_SIZE);
500
            munmap(dev_buffer, BS_SIZE);
501
        ipc_answer_0(rid, rc);
501
        ipc_answer_0(rid, rc);
502
        return;
502
        return;
503
    }
503
    }
504
 
504
 
505
    /* Initialize the root node. */
505
    /* Initialize the root node. */
506
    fat_node_t *rootp = (fat_node_t *)malloc(sizeof(fat_node_t));
506
    fat_node_t *rootp = (fat_node_t *)malloc(sizeof(fat_node_t));
507
    if (!rootp) {
507
    if (!rootp) {
508
            munmap(dev_buffer, BS_SIZE);
508
            munmap(dev_buffer, BS_SIZE);
509
        fat_idx_fini_by_dev_handle(dev_handle);
509
        fat_idx_fini_by_dev_handle(dev_handle);
510
        ipc_answer_0(rid, ENOMEM);
510
        ipc_answer_0(rid, ENOMEM);
511
        return;
511
        return;
512
    }
512
    }
513
    fat_node_initialize(rootp);
513
    fat_node_initialize(rootp);
514
 
514
 
515
    fat_idx_t *ridxp = fat_idx_get_by_pos(dev_handle, FAT_CLST_ROOTPAR, 0);
515
    fat_idx_t *ridxp = fat_idx_get_by_pos(dev_handle, FAT_CLST_ROOTPAR, 0);
516
    if (!ridxp) {
516
    if (!ridxp) {
517
            munmap(dev_buffer, BS_SIZE);
517
            munmap(dev_buffer, BS_SIZE);
518
        free(rootp);
518
        free(rootp);
519
        fat_idx_fini_by_dev_handle(dev_handle);
519
        fat_idx_fini_by_dev_handle(dev_handle);
520
        ipc_answer_0(rid, ENOMEM);
520
        ipc_answer_0(rid, ENOMEM);
521
        return;
521
        return;
522
    }
522
    }
523
    assert(ridxp->index == 0);
523
    assert(ridxp->index == 0);
524
    /* ridxp->lock held */
524
    /* ridxp->lock held */
525
 
525
 
526
    rootp->type = FAT_DIRECTORY;
526
    rootp->type = FAT_DIRECTORY;
527
    rootp->firstc = FAT_CLST_ROOT;
527
    rootp->firstc = FAT_CLST_ROOT;
528
    rootp->refcnt = 1;
528
    rootp->refcnt = 1;
529
    rootp->lnkcnt = 0;  /* FS root is not linked */
529
    rootp->lnkcnt = 0;  /* FS root is not linked */
530
    rootp->size = rde * sizeof(fat_dentry_t);
530
    rootp->size = rde * sizeof(fat_dentry_t);
531
    rootp->idx = ridxp;
531
    rootp->idx = ridxp;
532
    ridxp->nodep = rootp;
532
    ridxp->nodep = rootp;
533
   
533
   
534
    futex_up(&ridxp->lock);
534
    futex_up(&ridxp->lock);
535
 
535
 
536
    ipc_answer_3(rid, EOK, ridxp->index, rootp->size, rootp->lnkcnt);
536
    ipc_answer_3(rid, EOK, ridxp->index, rootp->size, rootp->lnkcnt);
537
}
537
}
538
 
538
 
539
void fat_mount(ipc_callid_t rid, ipc_call_t *request)
539
void fat_mount(ipc_callid_t rid, ipc_call_t *request)
540
{
540
{
541
    ipc_answer_0(rid, ENOTSUP);
541
    ipc_answer_0(rid, ENOTSUP);
542
}
542
}
543
 
543
 
544
void fat_lookup(ipc_callid_t rid, ipc_call_t *request)
544
void fat_lookup(ipc_callid_t rid, ipc_call_t *request)
545
{
545
{
546
    libfs_lookup(&fat_libfs_ops, fat_reg.fs_handle, rid, request);
546
    libfs_lookup(&fat_libfs_ops, fat_reg.fs_handle, rid, request);
547
}
547
}
548
 
548
 
549
void fat_read(ipc_callid_t rid, ipc_call_t *request)
549
void fat_read(ipc_callid_t rid, ipc_call_t *request)
550
{
550
{
551
    dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
551
    dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
552
    fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
552
    fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
553
    off_t pos = (off_t)IPC_GET_ARG3(*request);
553
    off_t pos = (off_t)IPC_GET_ARG3(*request);
554
    fat_node_t *nodep = (fat_node_t *)fat_node_get(dev_handle, index);
554
    fat_node_t *nodep = (fat_node_t *)fat_node_get(dev_handle, index);
555
    uint16_t bps = fat_bps_get(dev_handle);
555
    uint16_t bps = fat_bps_get(dev_handle);
556
    size_t bytes;
556
    size_t bytes;
557
    block_t *b;
557
    block_t *b;
558
 
558
 
559
    if (!nodep) {
559
    if (!nodep) {
560
        ipc_answer_0(rid, ENOENT);
560
        ipc_answer_0(rid, ENOENT);
561
        return;
561
        return;
562
    }
562
    }
563
 
563
 
564
    ipc_callid_t callid;
564
    ipc_callid_t callid;
565
    size_t len;
565
    size_t len;
566
    if (!ipc_data_read_receive(&callid, &len)) {
566
    if (!ipc_data_read_receive(&callid, &len)) {
567
        fat_node_put(nodep);
567
        fat_node_put(nodep);
568
        ipc_answer_0(callid, EINVAL);
568
        ipc_answer_0(callid, EINVAL);
569
        ipc_answer_0(rid, EINVAL);
569
        ipc_answer_0(rid, EINVAL);
570
        return;
570
        return;
571
    }
571
    }
572
 
572
 
573
    if (nodep->type == FAT_FILE) {
573
    if (nodep->type == FAT_FILE) {
574
        /*
574
        /*
575
         * Our strategy for regular file reads is to read one block at
575
         * Our strategy for regular file reads is to read one block at
576
         * most and make use of the possibility to return less data than
576
         * most and make use of the possibility to return less data than
577
         * requested. This keeps the code very simple.
577
         * requested. This keeps the code very simple.
578
         */
578
         */
579
        bytes = min(len, bps - pos % bps);
579
        bytes = min(len, bps - pos % bps);
580
        b = fat_block_get(nodep, pos / bps);
580
        b = fat_block_get(nodep, pos / bps);
581
        (void) ipc_data_read_finalize(callid, b->data + pos % bps,
581
        (void) ipc_data_read_finalize(callid, b->data + pos % bps,
582
            bytes);
582
            bytes);
583
        block_put(b);
583
        block_put(b);
584
    } else {
584
    } else {
585
        unsigned bnum;
585
        unsigned bnum;
586
        off_t spos = pos;
586
        off_t spos = pos;
587
        char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1];
587
        char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1];
588
        fat_dentry_t *d;
588
        fat_dentry_t *d;
589
 
589
 
590
        assert(nodep->type == FAT_DIRECTORY);
590
        assert(nodep->type == FAT_DIRECTORY);
591
        assert(nodep->size % bps == 0);
591
        assert(nodep->size % bps == 0);
592
        assert(bps % sizeof(fat_dentry_t) == 0);
592
        assert(bps % sizeof(fat_dentry_t) == 0);
593
 
593
 
594
        /*
594
        /*
595
         * Our strategy for readdir() is to use the position pointer as
595
         * Our strategy for readdir() is to use the position pointer as
596
         * an index into the array of all dentries. On entry, it points
596
         * an index into the array of all dentries. On entry, it points
597
         * to the first unread dentry. If we skip any dentries, we bump
597
         * to the first unread dentry. If we skip any dentries, we bump
598
         * the position pointer accordingly.
598
         * the position pointer accordingly.
599
         */
599
         */
600
        bnum = (pos * sizeof(fat_dentry_t)) / bps;
600
        bnum = (pos * sizeof(fat_dentry_t)) / bps;
601
        while (bnum < nodep->size / bps) {
601
        while (bnum < nodep->size / bps) {
602
            off_t o;
602
            off_t o;
603
 
603
 
604
            b = fat_block_get(nodep, bnum);
604
            b = fat_block_get(nodep, bnum);
605
            for (o = pos % (bps / sizeof(fat_dentry_t));
605
            for (o = pos % (bps / sizeof(fat_dentry_t));
606
                o < bps / sizeof(fat_dentry_t);
606
                o < bps / sizeof(fat_dentry_t);
607
                o++, pos++) {
607
                o++, pos++) {
608
                d = ((fat_dentry_t *)b->data) + o;
608
                d = ((fat_dentry_t *)b->data) + o;
609
                switch (fat_classify_dentry(d)) {
609
                switch (fat_classify_dentry(d)) {
610
                case FAT_DENTRY_SKIP:
610
                case FAT_DENTRY_SKIP:
611
                    continue;
611
                    continue;
612
                case FAT_DENTRY_LAST:
612
                case FAT_DENTRY_LAST:
613
                    block_put(b);
613
                    block_put(b);
614
                    goto miss;
614
                    goto miss;
615
                default:
615
                default:
616
                case FAT_DENTRY_VALID:
616
                case FAT_DENTRY_VALID:
617
                    dentry_name_canonify(d, name);
617
                    dentry_name_canonify(d, name);
618
                    block_put(b);
618
                    block_put(b);
619
                    goto hit;
619
                    goto hit;
620
                }
620
                }
621
            }
621
            }
622
            block_put(b);
622
            block_put(b);
623
            bnum++;
623
            bnum++;
624
        }
624
        }
625
miss:
625
miss:
626
        fat_node_put(nodep);
626
        fat_node_put(nodep);
627
        ipc_answer_0(callid, ENOENT);
627
        ipc_answer_0(callid, ENOENT);
628
        ipc_answer_1(rid, ENOENT, 0);
628
        ipc_answer_1(rid, ENOENT, 0);
629
        return;
629
        return;
630
hit:
630
hit:
631
        (void) ipc_data_read_finalize(callid, name, strlen(name) + 1);
631
        (void) ipc_data_read_finalize(callid, name, strlen(name) + 1);
632
        bytes = (pos - spos) + 1;
632
        bytes = (pos - spos) + 1;
633
    }
633
    }
634
 
634
 
635
    fat_node_put(nodep);
635
    fat_node_put(nodep);
636
    ipc_answer_1(rid, EOK, (ipcarg_t)bytes);
636
    ipc_answer_1(rid, EOK, (ipcarg_t)bytes);
637
}
637
}
638
 
638
 
639
void fat_write(ipc_callid_t rid, ipc_call_t *request)
639
void fat_write(ipc_callid_t rid, ipc_call_t *request)
640
{
640
{
641
    dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
641
    dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
642
    fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
642
    fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
643
    off_t pos = (off_t)IPC_GET_ARG3(*request);
643
    off_t pos = (off_t)IPC_GET_ARG3(*request);
644
    fat_node_t *nodep = (fat_node_t *)fat_node_get(dev_handle, index);
644
    fat_node_t *nodep = (fat_node_t *)fat_node_get(dev_handle, index);
645
    size_t bytes;
645
    size_t bytes;
646
    block_t *b, *bb;
646
    block_t *b, *bb;
647
    uint16_t bps;
647
    uint16_t bps;
648
    unsigned spc;
648
    unsigned spc;
649
    off_t boundary;
649
    off_t boundary;
650
   
650
   
651
    if (!nodep) {
651
    if (!nodep) {
652
        ipc_answer_0(rid, ENOENT);
652
        ipc_answer_0(rid, ENOENT);
653
        return;
653
        return;
654
    }
654
    }
655
   
655
   
656
    /* XXX remove me when you are ready */
656
    /* XXX remove me when you are ready */
657
    {
657
    {
658
        ipc_answer_0(rid, ENOTSUP);
658
        ipc_answer_0(rid, ENOTSUP);
659
        fat_node_put(nodep);
659
        fat_node_put(nodep);
660
        return;
660
        return;
661
    }
661
    }
662
 
662
 
663
    ipc_callid_t callid;
663
    ipc_callid_t callid;
664
    size_t len;
664
    size_t len;
665
    if (!ipc_data_write_receive(&callid, &len)) {
665
    if (!ipc_data_write_receive(&callid, &len)) {
666
        fat_node_put(nodep);
666
        fat_node_put(nodep);
667
        ipc_answer_0(callid, EINVAL);
667
        ipc_answer_0(callid, EINVAL);
668
        ipc_answer_0(rid, EINVAL);
668
        ipc_answer_0(rid, EINVAL);
669
        return;
669
        return;
670
    }
670
    }
671
 
671
 
672
    /*
672
    /*
673
     * In all scenarios, we will attempt to write out only one block worth
673
     * In all scenarios, we will attempt to write out only one block worth
674
     * of data at maximum. There might be some more efficient approaches,
674
     * of data at maximum. There might be some more efficient approaches,
675
     * but this one greatly simplifies fat_write(). Note that we can afford
675
     * but this one greatly simplifies fat_write(). Note that we can afford
676
     * to do this because the client must be ready to handle the return
676
     * to do this because the client must be ready to handle the return
677
     * value signalizing a smaller number of bytes written.
677
     * value signalizing a smaller number of bytes written.
678
     */
678
     */
679
    bytes = min(len, bps - pos % bps);
679
    bytes = min(len, bps - pos % bps);
680
 
680
 
681
    bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
681
    bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
682
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
682
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
683
    spc = FAT_BS(bb)->spc;
683
    spc = FAT_BS(bb)->spc;
684
    block_put(bb);
684
    block_put(bb);
685
   
685
   
686
    boundary = ROUND_UP(nodep->size, bps * spc);
686
    boundary = ROUND_UP(nodep->size, bps * spc);
687
    if (pos < boundary) {
687
    if (pos < boundary) {
688
        /*
688
        /*
689
         * This is the easier case - we are either overwriting already
689
         * This is the easier case - we are either overwriting already
690
         * existing contents or writing behind the EOF, but still within
690
         * existing contents or writing behind the EOF, but still within
691
         * the limits of the last cluster. The node size may grow to the
691
         * the limits of the last cluster. The node size may grow to the
692
         * next block size boundary.
692
         * next block size boundary.
693
         */
693
         */
694
        fat_fill_gap(nodep, FAT_CLST_RES0, pos);
694
        fat_fill_gap(nodep, FAT_CLST_RES0, pos);
695
        b = fat_block_get(nodep, pos / bps);
695
        b = fat_block_get(nodep, pos / bps);
696
        (void) ipc_data_write_finalize(callid, b->data + pos % bps,
696
        (void) ipc_data_write_finalize(callid, b->data + pos % bps,
697
            bytes);
697
            bytes);
698
        b->dirty = true;        /* need to sync block */
698
        b->dirty = true;        /* need to sync block */
699
        block_put(b);
699
        block_put(b);
700
        if (pos + bytes > nodep->size) {
700
        if (pos + bytes > nodep->size) {
701
            nodep->size = pos + bytes;
701
            nodep->size = pos + bytes;
702
            nodep->dirty = true;    /* need to sync node */
702
            nodep->dirty = true;    /* need to sync node */
703
        }
703
        }
704
        fat_node_put(nodep);
704
        fat_node_put(nodep);
705
        ipc_answer_1(rid, EOK, bytes); 
705
        ipc_answer_1(rid, EOK, bytes); 
706
        return;
706
        return;
707
    } else {
707
    } else {
708
        /*
708
        /*
709
         * This is the more difficult case. We must allocate new
709
         * This is the more difficult case. We must allocate new
710
         * clusters for the node and zero them out.
710
         * clusters for the node and zero them out.
711
         */
711
         */
712
        int status;
712
        int status;
713
        unsigned nclsts;
713
        unsigned nclsts;
714
        fat_cluster_t mcl, lcl;
714
        fat_cluster_t mcl, lcl;
715
   
715
   
716
        nclsts = (ROUND_UP(pos + bytes, bps * spc) - boundary) /
716
        nclsts = (ROUND_UP(pos + bytes, bps * spc) - boundary) /
717
            bps * spc;
717
            bps * spc;
718
        /* create an independent chain of nclsts clusters in all FATs */
718
        /* create an independent chain of nclsts clusters in all FATs */
719
        status = fat_alloc_clusters(dev_handle, nclsts, &mcl, &lcl);
719
        status = fat_alloc_clusters(dev_handle, nclsts, &mcl, &lcl);
720
        if (status != EOK) {
720
        if (status != EOK) {
721
            /* could not allocate a chain of nclsts clusters */
721
            /* could not allocate a chain of nclsts clusters */
722
            fat_node_put(nodep);
722
            fat_node_put(nodep);
723
            ipc_answer_0(callid, status);
723
            ipc_answer_0(callid, status);
724
            ipc_answer_0(rid, status);
724
            ipc_answer_0(rid, status);
725
            return;
725
            return;
726
        }
726
        }
727
        /* zero fill any gaps */
727
        /* zero fill any gaps */
728
        fat_fill_gap(nodep, mcl, pos);
728
        fat_fill_gap(nodep, mcl, pos);
729
        b = _fat_block_get(dev_handle, lcl, (pos / bps) % spc);
729
        b = _fat_block_get(dev_handle, lcl, (pos / bps) % spc);
730
        (void) ipc_data_write_finalize(callid, b->data + pos % bps,
730
        (void) ipc_data_write_finalize(callid, b->data + pos % bps,
731
            bytes);
731
            bytes);
732
        b->dirty = true;        /* need to sync block */
732
        b->dirty = true;        /* need to sync block */
733
        block_put(b);
733
        block_put(b);
734
        /*
734
        /*
735
         * Append the cluster chain starting in mcl to the end of the
735
         * Append the cluster chain starting in mcl to the end of the
736
         * node's cluster chain.
736
         * node's cluster chain.
737
         */
737
         */
738
        fat_append_clusters(nodep, mcl);
738
        fat_append_clusters(nodep, mcl);
739
        nodep->size = pos + bytes;
739
        nodep->size = pos + bytes;
740
        nodep->dirty = true;        /* need to sync node */
740
        nodep->dirty = true;        /* need to sync node */
741
        fat_node_put(nodep);
741
        fat_node_put(nodep);
742
        ipc_answer_1(rid, EOK, bytes);
742
        ipc_answer_1(rid, EOK, bytes);
743
        return;
743
        return;
744
    }
744
    }
745
}
745
}
746
 
746
 
747
/**
747
/**
748
 * @}
748
 * @}
749
 */
749
 */
750
 
750