WebSVN – HelenOS – Diff – /trunk/uspace/srv/fs/fat/fat_ops.c



 *
 * @param idxp      Locked index structure.
 */
static void *fat_node_get_core(fat_idx_t *idxp)
{
    block_t *bb, *b;
    fat_dentry_t *d;
    fat_node_t *nodep = NULL;
    unsigned bps;
    unsigned dps;
 

        if (!nodep)
            return NULL;
    }
    fat_node_initialize(nodep);
 
    bb = block_get(idxp->dev_handle, BS_BLOCK, BS_SIZE);
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
    dps = bps / sizeof(fat_dentry_t);
 
    /* Read the block that contains the dentry of interest. */
    b = _fat_block_get(bb->data, idxp->dev_handle, idxp->pfc,
        (idxp->pdi * sizeof(fat_dentry_t)) / bps);
    assert(b);
 
    d = ((fat_dentry_t *)b->data) + (idxp->pdi % dps);
    if (d->attr & FAT_ATTR_SUBDIR) {

        /*
         * Unfortunately, the 'size' field of the FAT dentry is not
         * defined for the directory entry type. We must determine the
         * size of the directory by walking the FAT.
         */
        nodep->size = bps * _fat_blcks_get(bb->data, idxp->dev_handle,
            uint16_t_le2host(d->firstc), NULL);
    } else {
        nodep->type = FAT_FILE;
        nodep->size = uint32_t_le2host(d->size);
    }
    nodep->firstc = uint16_t_le2host(d->firstc);
    nodep->lnkcnt = 1;
    nodep->refcnt = 1;
 
    block_put(b);
    block_put(bb);
 
    /* Link the idx structure with the node structure. */
    nodep->idx = idxp;
    idxp->nodep = nodep;
 

    unsigned i, j;
    unsigned bps;       /* bytes per sector */
    unsigned dps;       /* dentries per sector */
    unsigned blocks;
    fat_dentry_t *d;
    block_t *bb, *b;
 
    futex_down(&parentp->idx->lock);
    bb = block_get(parentp->idx->dev_handle, BS_BLOCK, BS_SIZE);
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
    dps = bps / sizeof(fat_dentry_t);
    blocks = parentp->size / bps + (parentp->size % bps != 0);
    for (i = 0; i < blocks; i++) {
        unsigned dentries;
       
        b = fat_block_get(bb->data, parentp, i);
        dentries = (i == blocks - 1) ?
            parentp->size % sizeof(fat_dentry_t) :
            dps;
        for (j = 0; j < dentries; j++) {
            d = ((fat_dentry_t *)b->data) + j;
            switch (fat_classify_dentry(d)) {
            case FAT_DENTRY_SKIP:
                continue;
            case FAT_DENTRY_LAST:
                block_put(b);
                block_put(bb);
                futex_up(&parentp->idx->lock);
                return NULL;
            default:
            case FAT_DENTRY_VALID:
                dentry_name_canonify(d, name);

                    /*
                     * Can happen if memory is low or if we
                     * run out of 32-bit indices.
                     */
                    block_put(b);
                    block_put(bb);
                    return NULL;
                }
                node = fat_node_get_core(idx);
                futex_up(&idx->lock);
                block_put(b);
                block_put(bb);
                return node;
            }
        }
        block_put(b);
    }
    block_put(bb);
 
    futex_up(&parentp->idx->lock);
    return NULL;
}
 
static fs_index_t fat_index_get(void *node)

{
    fat_node_t *nodep = (fat_node_t *)node;
    unsigned bps;
    unsigned dps;
    unsigned blocks;
    block_t *bb, *b;
    unsigned i, j;
 
    if (nodep->type != FAT_DIRECTORY)
        return false;
 
    futex_down(&nodep->idx->lock);
    bb = block_get(nodep->idx->dev_handle, BS_BLOCK, BS_SIZE);
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
    dps = bps / sizeof(fat_dentry_t);
 
    blocks = nodep->size / bps + (nodep->size % bps != 0);
 
    for (i = 0; i < blocks; i++) {
        unsigned dentries;
        fat_dentry_t *d;
   
        b = fat_block_get(bb->data, nodep, i);
        dentries = (i == blocks - 1) ?
            nodep->size % sizeof(fat_dentry_t) :
            dps;
        for (j = 0; j < dentries; j++) {
            d = ((fat_dentry_t *)b->data) + j;
            switch (fat_classify_dentry(d)) {
            case FAT_DENTRY_SKIP:
                continue;
            case FAT_DENTRY_LAST:
                block_put(b);
                block_put(bb);
                futex_up(&nodep->idx->lock);
                return false;
            default:
            case FAT_DENTRY_VALID:
                block_put(b);
                block_put(bb);
                futex_up(&nodep->idx->lock);
                return true;
            }
            block_put(b);
            block_put(bb);
            futex_up(&nodep->idx->lock);
            return true;
        }
        block_put(b);
    }
    block_put(bb);
 
    futex_up(&nodep->idx->lock);
    return false;
}
 

{
    dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
    fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
    off_t pos = (off_t)IPC_GET_ARG3(*request);
    fat_node_t *nodep = (fat_node_t *)fat_node_get(dev_handle, index);
    uint16_t bps;
    size_t bytes;
    block_t *bb, *b;
 
    if (!nodep) {
        ipc_answer_0(rid, ENOENT);
        return;
    }

        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
 
    bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
 
    if (nodep->type == FAT_FILE) {
        /*
         * Our strategy for regular file reads is to read one block at
         * most and make use of the possibility to return less data than
         * requested. This keeps the code very simple.
         */
        bytes = min(len, bps - pos % bps);
        b = fat_block_get(bb->data, nodep, pos / bps);
        (void) ipc_data_read_finalize(callid, b->data + pos % bps,
            bytes);
        block_put(b);
    } else {
        unsigned bnum;

         */
        bnum = (pos * sizeof(fat_dentry_t)) / bps;
        while (bnum < nodep->size / bps) {
            off_t o;
 
            b = fat_block_get(bb->data, nodep, bnum);
            for (o = pos % (bps / sizeof(fat_dentry_t));
                o < bps / sizeof(fat_dentry_t);
                o++, pos++) {
                d = ((fat_dentry_t *)b->data) + o;
                switch (fat_classify_dentry(d)) {

            block_put(b);
            bnum++;
        }
miss:
        fat_node_put(nodep);
        block_put(bb);
        ipc_answer_0(callid, ENOENT);
        ipc_answer_1(rid, ENOENT, 0);
        return;
hit:
        (void) ipc_data_read_finalize(callid, name, strlen(name) + 1);
        bytes = (pos - spos) + 1;
    }
 
    fat_node_put(nodep);
    block_put(bb);
    ipc_answer_1(rid, EOK, (ipcarg_t)bytes);
}
 
void fat_write(ipc_callid_t rid, ipc_call_t *request)
{

    bytes = min(len, bps - pos % bps);
 
    bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
    bps = uint16_t_le2host(FAT_BS(bb)->bps);
    spc = FAT_BS(bb)->spc;
 
   
    boundary = ROUND_UP(nodep->size, bps * spc);
    if (pos < boundary) {
        /*
         * This is the easier case - we are either overwriting already
         * existing contents or writing behind the EOF, but still within
         * the limits of the last cluster. The node size may grow to the
         * next block size boundary.
         */
        fat_fill_gap(bb->data, nodep, FAT_CLST_RES0, pos);
        b = fat_block_get(bb->data, nodep, pos / bps);
        (void) ipc_data_write_finalize(callid, b->data + pos % bps,
            bytes);
        b->dirty = true;        /* need to sync block */
        block_put(b);
        if (pos + bytes > nodep->size) {
            nodep->size = pos + bytes;
            nodep->dirty = true;    /* need to sync node */
        }
        fat_node_put(nodep);
        block_put(bb);
        ipc_answer_1(rid, EOK, bytes); 
        return;
    } else {
        /*
         * This is the more difficult case. We must allocate new

        fat_cluster_t mcl, lcl;
   
        nclsts = (ROUND_UP(pos + bytes, bps * spc) - boundary) /
            bps * spc;
        /* create an independent chain of nclsts clusters in all FATs */
        status = fat_alloc_clusters(bb->data, dev_handle, nclsts, &mcl,
            &lcl);
        if (status != EOK) {
            /* could not allocate a chain of nclsts clusters */
            fat_node_put(nodep);
            block_put(bb);
            ipc_answer_0(callid, status);
            ipc_answer_0(rid, status);
            return;
        }
        /* zero fill any gaps */
        fat_fill_gap(bb->data, nodep, mcl, pos);
        b = _fat_block_get(bb->data, dev_handle, lcl,
            (pos / bps) % spc);
        (void) ipc_data_write_finalize(callid, b->data + pos % bps,
            bytes);
        b->dirty = true;        /* need to sync block */
        block_put(b);
        /*
         * Append the cluster chain starting in mcl to the end of the
         * node's cluster chain.
         */
        fat_append_clusters(bb->data, nodep, mcl);
        nodep->size = pos + bytes;
        nodep->dirty = true;        /* need to sync node */
        fat_node_put(nodep);
        block_put(bb);
        ipc_answer_1(rid, EOK, bytes);
        return;
    }
}
 

Rev 3513	Rev 3516
Line 123...	Line 123...
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 bb, 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
Line 176...	Line 176...
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	bb = block_get(idxp->dev_handle, BS_BLOCK, BS_SIZE);
-		182	bps = uint16_t_le2host(FAT_BS(bb)->bps);
182	dps = bps / sizeof(fat_dentry_t);	183	dps = bps / sizeof(fat_dentry_t);
183		184
184	/* Read the block that contains the dentry of interest. */	185	/* Read the block that contains the dentry of interest. */
185	b = _fat_block_get(idxp->dev_handle, idxp->pfc,	186	b = _fat_block_get(bb->data, idxp->dev_handle, idxp->pfc,
186	(idxp->pdi * sizeof(fat_dentry_t)) / bps);	187	(idxp->pdi * sizeof(fat_dentry_t)) / bps);
187	assert(b);	188	assert(b);
188		189
189	d = ((fat_dentry_t *)b->data) + (idxp->pdi % dps);	190	d = ((fat_dentry_t *)b->data) + (idxp->pdi % dps);
190	if (d->attr & FAT_ATTR_SUBDIR) {	191	if (d->attr & FAT_ATTR_SUBDIR) {
Line 197...	Line 198...
197	/*	198	/*
198	* Unfortunately, the 'size' field of the FAT dentry is not	199	* Unfortunately, the 'size' field of the FAT dentry is not
199	* defined for the directory entry type. We must determine the	200	* defined for the directory entry type. We must determine the
200	* size of the directory by walking the FAT.	201	* size of the directory by walking the FAT.
201	*/	202	*/
202	nodep->size = bps * _fat_blcks_get(idxp->dev_handle,	203	nodep->size = bps * _fat_blcks_get(bb->data, idxp->dev_handle,
203	uint16_t_le2host(d->firstc), NULL);	204	uint16_t_le2host(d->firstc), NULL);
204	} else {	205	} else {
205	nodep->type = FAT_FILE;	206	nodep->type = FAT_FILE;
206	nodep->size = uint32_t_le2host(d->size);	207	nodep->size = uint32_t_le2host(d->size);
207	}	208	}
208	nodep->firstc = uint16_t_le2host(d->firstc);	209	nodep->firstc = uint16_t_le2host(d->firstc);
209	nodep->lnkcnt = 1;	210	nodep->lnkcnt = 1;
210	nodep->refcnt = 1;	211	nodep->refcnt = 1;
211		212
212	block_put(b);	213	block_put(b);
-		214	block_put(bb);
213		215
214	/* Link the idx structure with the node structure. */	216	/* Link the idx structure with the node structure. */
215	nodep->idx = idxp;	217	nodep->idx = idxp;
216	idxp->nodep = nodep;	218	idxp->nodep = nodep;
217		219
Line 273...	Line 275...
273	unsigned i, j;	275	unsigned i, j;
274	unsigned bps; /* bytes per sector */	276	unsigned bps; /* bytes per sector */
275	unsigned dps; /* dentries per sector */	277	unsigned dps; /* dentries per sector */
276	unsigned blocks;	278	unsigned blocks;
277	fat_dentry_t *d;	279	fat_dentry_t *d;
278	block_t *b;	280	block_t bb, b;
279		281
280	futex_down(&parentp->idx->lock);	282	futex_down(&parentp->idx->lock);
281	bps = fat_bps_get(parentp->idx->dev_handle);	283	bb = block_get(parentp->idx->dev_handle, BS_BLOCK, BS_SIZE);
-		284	bps = uint16_t_le2host(FAT_BS(bb)->bps);
282	dps = bps / sizeof(fat_dentry_t);	285	dps = bps / sizeof(fat_dentry_t);
283	blocks = parentp->size / bps + (parentp->size % bps != 0);	286	blocks = parentp->size / bps + (parentp->size % bps != 0);
284	for (i = 0; i < blocks; i++) {	287	for (i = 0; i < blocks; i++) {
285	unsigned dentries;	288	unsigned dentries;
286		289
287	b = fat_block_get(parentp, i);	290	b = fat_block_get(bb->data, parentp, i);
288	dentries = (i == blocks - 1) ?	291	dentries = (i == blocks - 1) ?
289	parentp->size % sizeof(fat_dentry_t) :	292	parentp->size % sizeof(fat_dentry_t) :
290	dps;	293	dps;
291	for (j = 0; j < dentries; j++) {	294	for (j = 0; j < dentries; j++) {
292	d = ((fat_dentry_t *)b->data) + j;	295	d = ((fat_dentry_t *)b->data) + j;
293	switch (fat_classify_dentry(d)) {	296	switch (fat_classify_dentry(d)) {
294	case FAT_DENTRY_SKIP:	297	case FAT_DENTRY_SKIP:
295	continue;	298	continue;
296	case FAT_DENTRY_LAST:	299	case FAT_DENTRY_LAST:
297	block_put(b);	300	block_put(b);
-		301	block_put(bb);
298	futex_up(&parentp->idx->lock);	302	futex_up(&parentp->idx->lock);
299	return NULL;	303	return NULL;
300	default:	304	default:
301	case FAT_DENTRY_VALID:	305	case FAT_DENTRY_VALID:
302	dentry_name_canonify(d, name);	306	dentry_name_canonify(d, name);
Line 319...	Line 323...
319	/*	323	/*
320	* Can happen if memory is low or if we	324	* Can happen if memory is low or if we
321	* run out of 32-bit indices.	325	* run out of 32-bit indices.
322	*/	326	*/
323	block_put(b);	327	block_put(b);
-		328	block_put(bb);
324	return NULL;	329	return NULL;
325	}	330	}
326	node = fat_node_get_core(idx);	331	node = fat_node_get_core(idx);
327	futex_up(&idx->lock);	332	futex_up(&idx->lock);
328	block_put(b);	333	block_put(b);
-		334	block_put(bb);
329	return node;	335	return node;
330	}	336	}
331	}	337	}
332	block_put(b);	338	block_put(b);
333	}	339	}
-		340	block_put(bb);
-		341
334	futex_up(&parentp->idx->lock);	342	futex_up(&parentp->idx->lock);
335	return NULL;	343	return NULL;
336	}	344	}
337		345
338	static fs_index_t fat_index_get(void *node)	346	static fs_index_t fat_index_get(void *node)
Line 357...	Line 365...
357	{	365	{
358	fat_node_t nodep = (fat_node_t )node;	366	fat_node_t nodep = (fat_node_t )node;
359	unsigned bps;	367	unsigned bps;
360	unsigned dps;	368	unsigned dps;
361	unsigned blocks;	369	unsigned blocks;
362	block_t *b;	370	block_t bb, b;
363	unsigned i, j;	371	unsigned i, j;
364		372
365	if (nodep->type != FAT_DIRECTORY)	373	if (nodep->type != FAT_DIRECTORY)
366	return false;	374	return false;
367		375
368	futex_down(&nodep->idx->lock);	376	futex_down(&nodep->idx->lock);
369	bps = fat_bps_get(nodep->idx->dev_handle);	377	bb = block_get(nodep->idx->dev_handle, BS_BLOCK, BS_SIZE);
-		378	bps = uint16_t_le2host(FAT_BS(bb)->bps);
370	dps = bps / sizeof(fat_dentry_t);	379	dps = bps / sizeof(fat_dentry_t);
371		380
372	blocks = nodep->size / bps + (nodep->size % bps != 0);	381	blocks = nodep->size / bps + (nodep->size % bps != 0);
373		382
374	for (i = 0; i < blocks; i++) {	383	for (i = 0; i < blocks; i++) {
375	unsigned dentries;	384	unsigned dentries;
376	fat_dentry_t *d;	385	fat_dentry_t *d;
377		386
378	b = fat_block_get(nodep, i);	387	b = fat_block_get(bb->data, nodep, i);
379	dentries = (i == blocks - 1) ?	388	dentries = (i == blocks - 1) ?
380	nodep->size % sizeof(fat_dentry_t) :	389	nodep->size % sizeof(fat_dentry_t) :
381	dps;	390	dps;
382	for (j = 0; j < dentries; j++) {	391	for (j = 0; j < dentries; j++) {
383	d = ((fat_dentry_t *)b->data) + j;	392	d = ((fat_dentry_t *)b->data) + j;
384	switch (fat_classify_dentry(d)) {	393	switch (fat_classify_dentry(d)) {
385	case FAT_DENTRY_SKIP:	394	case FAT_DENTRY_SKIP:
386	continue;	395	continue;
387	case FAT_DENTRY_LAST:	396	case FAT_DENTRY_LAST:
388	block_put(b);	397	block_put(b);
-		398	block_put(bb);
389	futex_up(&nodep->idx->lock);	399	futex_up(&nodep->idx->lock);
390	return false;	400	return false;
391	default:	401	default:
392	case FAT_DENTRY_VALID:	402	case FAT_DENTRY_VALID:
393	block_put(b);	403	block_put(b);
-		404	block_put(bb);
394	futex_up(&nodep->idx->lock);	405	futex_up(&nodep->idx->lock);
395	return true;	406	return true;
396	}	407	}
397	block_put(b);	408	block_put(b);
-		409	block_put(bb);
398	futex_up(&nodep->idx->lock);	410	futex_up(&nodep->idx->lock);
399	return true;	411	return true;
400	}	412	}
401	block_put(b);	413	block_put(b);
402	}	414	}
-		415	block_put(bb);
403		416
404	futex_up(&nodep->idx->lock);	417	futex_up(&nodep->idx->lock);
405	return false;	418	return false;
406	}	419	}
407		420
Line 550...	Line 563...
550	{	563	{
551	dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);	564	dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
552	fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);	565	fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
553	off_t pos = (off_t)IPC_GET_ARG3(*request);	566	off_t pos = (off_t)IPC_GET_ARG3(*request);
554	fat_node_t nodep = (fat_node_t )fat_node_get(dev_handle, index);	567	fat_node_t nodep = (fat_node_t )fat_node_get(dev_handle, index);
555	uint16_t bps = fat_bps_get(dev_handle);	568	uint16_t bps;
556	size_t bytes;	569	size_t bytes;
557	block_t *b;	570	block_t bb, b;
558		571
559	if (!nodep) {	572	if (!nodep) {
560	ipc_answer_0(rid, ENOENT);	573	ipc_answer_0(rid, ENOENT);
561	return;	574	return;
562	}	575	}
Line 568...	Line 581...
568	ipc_answer_0(callid, EINVAL);	581	ipc_answer_0(callid, EINVAL);
569	ipc_answer_0(rid, EINVAL);	582	ipc_answer_0(rid, EINVAL);
570	return;	583	return;
571	}	584	}
572		585
-		586	bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
-		587	bps = uint16_t_le2host(FAT_BS(bb)->bps);
-		588
573	if (nodep->type == FAT_FILE) {	589	if (nodep->type == FAT_FILE) {
574	/*	590	/*
575	* Our strategy for regular file reads is to read one block at	591	* 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	592	* most and make use of the possibility to return less data than
577	* requested. This keeps the code very simple.	593	* requested. This keeps the code very simple.
578	*/	594	*/
579	bytes = min(len, bps - pos % bps);	595	bytes = min(len, bps - pos % bps);
580	b = fat_block_get(nodep, pos / bps);	596	b = fat_block_get(bb->data, nodep, pos / bps);
581	(void) ipc_data_read_finalize(callid, b->data + pos % bps,	597	(void) ipc_data_read_finalize(callid, b->data + pos % bps,
582	bytes);	598	bytes);
583	block_put(b);	599	block_put(b);
584	} else {	600	} else {
585	unsigned bnum;	601	unsigned bnum;
Line 599...	Line 615...
599	*/	615	*/
600	bnum = (pos * sizeof(fat_dentry_t)) / bps;	616	bnum = (pos * sizeof(fat_dentry_t)) / bps;
601	while (bnum < nodep->size / bps) {	617	while (bnum < nodep->size / bps) {
602	off_t o;	618	off_t o;
603		619
604	b = fat_block_get(nodep, bnum);	620	b = fat_block_get(bb->data, nodep, bnum);
605	for (o = pos % (bps / sizeof(fat_dentry_t));	621	for (o = pos % (bps / sizeof(fat_dentry_t));
606	o < bps / sizeof(fat_dentry_t);	622	o < bps / sizeof(fat_dentry_t);
607	o++, pos++) {	623	o++, pos++) {
608	d = ((fat_dentry_t *)b->data) + o;	624	d = ((fat_dentry_t *)b->data) + o;
609	switch (fat_classify_dentry(d)) {	625	switch (fat_classify_dentry(d)) {
Line 622...	Line 638...
622	block_put(b);	638	block_put(b);
623	bnum++;	639	bnum++;
624	}	640	}
625	miss:	641	miss:
626	fat_node_put(nodep);	642	fat_node_put(nodep);
-		643	block_put(bb);
627	ipc_answer_0(callid, ENOENT);	644	ipc_answer_0(callid, ENOENT);
628	ipc_answer_1(rid, ENOENT, 0);	645	ipc_answer_1(rid, ENOENT, 0);
629	return;	646	return;
630	hit:	647	hit:
631	(void) ipc_data_read_finalize(callid, name, strlen(name) + 1);	648	(void) ipc_data_read_finalize(callid, name, strlen(name) + 1);
632	bytes = (pos - spos) + 1;	649	bytes = (pos - spos) + 1;
633	}	650	}
634		651
635	fat_node_put(nodep);	652	fat_node_put(nodep);
-		653	block_put(bb);
636	ipc_answer_1(rid, EOK, (ipcarg_t)bytes);	654	ipc_answer_1(rid, EOK, (ipcarg_t)bytes);
637	}	655	}
638		656
639	void fat_write(ipc_callid_t rid, ipc_call_t *request)	657	void fat_write(ipc_callid_t rid, ipc_call_t *request)
640	{	658	{
Line 679...	Line 697...
679	bytes = min(len, bps - pos % bps);	697	bytes = min(len, bps - pos % bps);
680		698
681	bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);	699	bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
682	bps = uint16_t_le2host(FAT_BS(bb)->bps);	700	bps = uint16_t_le2host(FAT_BS(bb)->bps);
683	spc = FAT_BS(bb)->spc;	701	spc = FAT_BS(bb)->spc;
684	block_put(bb);	-
685		702
686	boundary = ROUND_UP(nodep->size, bps * spc);	703	boundary = ROUND_UP(nodep->size, bps * spc);
687	if (pos < boundary) {	704	if (pos < boundary) {
688	/*	705	/*
689	* This is the easier case - we are either overwriting already	706	* This is the easier case - we are either overwriting already
690	* existing contents or writing behind the EOF, but still within	707	* existing contents or writing behind the EOF, but still within
691	* the limits of the last cluster. The node size may grow to the	708	* the limits of the last cluster. The node size may grow to the
692	* next block size boundary.	709	* next block size boundary.
693	*/	710	*/
694	fat_fill_gap(nodep, FAT_CLST_RES0, pos);	711	fat_fill_gap(bb->data, nodep, FAT_CLST_RES0, pos);
695	b = fat_block_get(nodep, pos / bps);	712	b = fat_block_get(bb->data, nodep, pos / bps);
696	(void) ipc_data_write_finalize(callid, b->data + pos % bps,	713	(void) ipc_data_write_finalize(callid, b->data + pos % bps,
697	bytes);	714	bytes);
698	b->dirty = true; /* need to sync block */	715	b->dirty = true; /* need to sync block */
699	block_put(b);	716	block_put(b);
700	if (pos + bytes > nodep->size) {	717	if (pos + bytes > nodep->size) {
701	nodep->size = pos + bytes;	718	nodep->size = pos + bytes;
702	nodep->dirty = true; /* need to sync node */	719	nodep->dirty = true; /* need to sync node */
703	}	720	}
704	fat_node_put(nodep);	721	fat_node_put(nodep);
-		722	block_put(bb);
705	ipc_answer_1(rid, EOK, bytes);	723	ipc_answer_1(rid, EOK, bytes);
706	return;	724	return;
707	} else {	725	} else {
708	/*	726	/*
709	* This is the more difficult case. We must allocate new	727	* This is the more difficult case. We must allocate new
Line 714...	Line 732...
714	fat_cluster_t mcl, lcl;	732	fat_cluster_t mcl, lcl;
715		733
716	nclsts = (ROUND_UP(pos + bytes, bps * spc) - boundary) /	734	nclsts = (ROUND_UP(pos + bytes, bps * spc) - boundary) /
717	bps * spc;	735	bps * spc;
718	/* create an independent chain of nclsts clusters in all FATs */	736	/* create an independent chain of nclsts clusters in all FATs */
719	status = fat_alloc_clusters(dev_handle, nclsts, &mcl, &lcl);	737	status = fat_alloc_clusters(bb->data, dev_handle, nclsts, &mcl,
-		738	&lcl);
720	if (status != EOK) {	739	if (status != EOK) {
721	/* could not allocate a chain of nclsts clusters */	740	/* could not allocate a chain of nclsts clusters */
722	fat_node_put(nodep);	741	fat_node_put(nodep);
-		742	block_put(bb);
723	ipc_answer_0(callid, status);	743	ipc_answer_0(callid, status);
724	ipc_answer_0(rid, status);	744	ipc_answer_0(rid, status);
725	return;	745	return;
726	}	746	}
727	/* zero fill any gaps */	747	/* zero fill any gaps */
728	fat_fill_gap(nodep, mcl, pos);	748	fat_fill_gap(bb->data, nodep, mcl, pos);
729	b = _fat_block_get(dev_handle, lcl, (pos / bps) % spc);	749	b = _fat_block_get(bb->data, dev_handle, lcl,
-		750	(pos / bps) % spc);
730	(void) ipc_data_write_finalize(callid, b->data + pos % bps,	751	(void) ipc_data_write_finalize(callid, b->data + pos % bps,
731	bytes);	752	bytes);
732	b->dirty = true; /* need to sync block */	753	b->dirty = true; /* need to sync block */
733	block_put(b);	754	block_put(b);
734	/*	755	/*
735	* Append the cluster chain starting in mcl to the end of the	756	* Append the cluster chain starting in mcl to the end of the
736	* node's cluster chain.	757	* node's cluster chain.
737	*/	758	*/
738	fat_append_clusters(nodep, mcl);	759	fat_append_clusters(bb->data, nodep, mcl);
739	nodep->size = pos + bytes;	760	nodep->size = pos + bytes;
740	nodep->dirty = true; /* need to sync node */	761	nodep->dirty = true; /* need to sync node */
741	fat_node_put(nodep);	762	fat_node_put(nodep);
-		763	block_put(bb);
742	ipc_answer_1(rid, EOK, bytes);	764	ipc_answer_1(rid, EOK, bytes);
743	return;	765	return;
744	}	766	}
745	}	767	}
746		768

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/fs/fat/fat_ops.c @ 4680 – Rev 3513 → 3516