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Ignore whitespace Rev 3571 → Rev 3572

/trunk/uspace/srv/fs/fat/fat_fat.c
129,7 → 129,7
unsigned sf;
unsigned ssa; /* size of the system area */
unsigned clusters, max_clusters;
fat_cluster_t lastc, clst = firstc;
fat_cluster_t lastc;
 
bps = uint16_t_le2host(bs->bps);
rscnt = uint16_t_le2host(bs->rscnt);
158,7 → 158,6
return b;
}
 
 
/** Fill the gap between EOF and a new file position.
*
* @param bs Buffer holding the boot sector for nodep.
203,16 → 202,43
}
}
 
/** Mark cluster in one instance of FAT.
/** Get cluster from the first FAT.
*
* @param bs Buffer holding the boot sector for the file system.
* @param dev_handle Device handle for the file system.
* @param clst Cluster which to get.
*
* @return Value found in the cluster.
*/
fat_cluster_t
fat_get_cluster(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t clst)
{
block_t *b;
uint16_t bps;
uint16_t rscnt;
fat_cluster_t *cp, value;
 
bps = uint16_t_le2host(bs->bps);
rscnt = uint16_t_le2host(bs->rscnt);
 
b = block_get(dev_handle, rscnt + (clst * sizeof(fat_cluster_t)) / bps);
cp = (fat_cluster_t *)b->data + clst % (bps / sizeof(fat_cluster_t));
value = uint16_t_le2host(*cp);
block_put(b);
return value;
}
 
/** Set cluster in one instance of FAT.
*
* @param bs Buffer holding the boot sector for the file system.
* @param dev_handle Device handle for the file system.
* @param fatno Number of the FAT instance where to make the change.
* @param clst Cluster which is to be marked.
* @param value Value mark the cluster with.
* @param clst Cluster which is to be set.
* @param value Value to set the cluster with.
*/
void
fat_mark_cluster(fat_bs_t *bs, dev_handle_t dev_handle, unsigned fatno,
fat_set_cluster(fat_bs_t *bs, dev_handle_t dev_handle, unsigned fatno,
fat_cluster_t clst, fat_cluster_t value)
{
block_t *b;
249,7 → 275,7
 
for (fatno = FAT1 + 1; fatno < bs->fatcnt; fatno++) {
for (c = 0; c < nclsts; c++) {
fat_mark_cluster(bs, dev_handle, fatno, lifo[c],
fat_set_cluster(bs, dev_handle, fatno, lifo[c],
c == 0 ? FAT_CLST_LAST1 : lifo[c - 1]);
}
}
333,7 → 359,7
* we have allocated so far.
*/
while (found--) {
fat_mark_cluster(bs, dev_handle, FAT1, lifo[found],
fat_set_cluster(bs, dev_handle, FAT1, lifo[found],
FAT_CLST_RES0);
}
341,9 → 367,32
return ENOSPC;
}
 
/** Free clusters forming a cluster chain in all copies of FAT.
*
* @param bs Buffer hodling the boot sector of the file system.
* @param dev_handle Device handle of the file system.
* @param firstc First cluster in the chain which is to be freed.
*/
void
fat_free_clusters(fat_bs_t *bs, dev_handle_t dev_handle, fat_cluster_t firstc)
{
unsigned fatno;
fat_cluster_t nextc;
 
/* Mark all clusters in the chain as free in all copies of FAT. */
while (firstc < FAT_CLST_LAST1) {
nextc = fat_get_cluster(bs, dev_handle, firstc);
assert(nextc >= FAT_CLST_FIRST && nextc < FAT_CLST_BAD);
for (fatno = FAT1; fatno < bs->fatcnt; fatno++)
fat_set_cluster(bs, dev_handle, fatno, firstc,
FAT_CLST_RES0);
firstc = nextc;
}
}
 
/** Append a cluster chain to the last file cluster in all FATs.
*
* @param bs Buffer holding boot sector of the file system.
* @param bs Buffer holding the boot sector of the file system.
* @param nodep Node representing the file.
* @param mcl First cluster of the cluster chain to append.
*/
353,7 → 402,7
fat_cluster_t lcl;
uint8_t fatno;
 
if (fat_cluster_walk(bs, nodep->idx->dev_handle, nodep->firstc, &lcl,
if (fat_cluster_walk(bs, dev_handle, nodep->firstc, &lcl,
(uint16_t) -1) == 0) {
/* No clusters allocated to the node yet. */
nodep->firstc = host2uint16_t_le(mcl);
362,9 → 411,40
}
 
for (fatno = FAT1; fatno < bs->fatcnt; fatno++)
fat_mark_cluster(bs, nodep->idx->dev_handle, fatno, lcl, mcl);
fat_set_cluster(bs, nodep->idx->dev_handle, fatno, lcl, mcl);
}
 
/** Chop off node clusters in all copies of FAT.
*
* @param bs Buffer holding the boot sector of the file system.
* @param nodep FAT node where the chopping will take place.
* @param lastc Last cluster which will remain in the node. If this
* argument is FAT_CLST_RES0, then all clusters will
* be choped off.
*/
void fat_chop_clusters(fat_bs_t *bs, fat_node_t *nodep, fat_cluster_t lastc)
{
dev_handle_t dev_handle = nodep->idx->dev_handle;
if (lastc == FAT_CLST_RES0) {
/* The node will have zero size and no clusters allocated. */
fat_free_clusters(bs, dev_handle, nodep->firstc);
nodep->firstc = FAT_CLST_RES0;
nodep->dirty = true; /* need to sync node */
} else {
fat_cluster_t nextc;
unsigned fatno;
 
nextc = fat_get_cluster(bs, dev_handle, lastc);
 
/* Terminate the cluster chain in all copies of FAT. */
for (fatno = FAT1; fatno < bs->fatcnt; fatno++)
fat_set_cluster(bs, dev_handle, fatno, lastc, FAT_CLST_LAST1);
 
/* Free all following clusters. */
fat_free_clusters(bs, dev_handle, nextc);
}
}
 
/**
* @}
*/
/trunk/uspace/srv/fs/fat/fat_fat.h
71,11 → 71,15
extern void fat_append_clusters(struct fat_bs *, struct fat_node *,
fat_cluster_t);
extern void fat_chop_clusters(struct fat_bs *, struct fat_node *,
fat_cluster_t);
extern int fat_alloc_clusters(struct fat_bs *, dev_handle_t, unsigned,
fat_cluster_t *, fat_cluster_t *);
extern void fat_free_clusters(struct fat_bs *, dev_handle_t, fat_cluster_t);
extern void fat_alloc_shadow_clusters(struct fat_bs *, dev_handle_t,
fat_cluster_t *, unsigned);
extern void fat_mark_cluster(struct fat_bs *, dev_handle_t, unsigned,
extern fat_cluster_t fat_get_cluster(struct fat_bs *, dev_handle_t, fat_cluster_t);
extern void fat_set_cluster(struct fat_bs *, dev_handle_t, unsigned,
fat_cluster_t, fat_cluster_t);
extern void fat_fill_gap(struct fat_bs *, struct fat_node *, fat_cluster_t,
off_t);
/trunk/uspace/srv/fs/fat/fat_ops.c
634,6 → 634,7
block_t *b;
uint16_t bps;
unsigned spc;
unsigned bpc; /* bytes per cluster */
off_t boundary;
if (!nodep) {
650,6 → 651,11
return;
}
 
bs = block_bb_get(dev_handle);
bps = uint16_t_le2host(bs->bps);
spc = bs->spc;
bpc = bps * spc;
 
/*
* In all scenarios, we will attempt to write out only one block worth
* of data at maximum. There might be some more efficient approaches,
658,12 → 664,8
* value signalizing a smaller number of bytes written.
*/
bytes = min(len, bps - pos % bps);
 
bs = block_bb_get(dev_handle);
bps = uint16_t_le2host(bs->bps);
spc = bs->spc;
boundary = ROUND_UP(nodep->size, bps * spc);
boundary = ROUND_UP(nodep->size, bpc);
if (pos < boundary) {
/*
* This is the easier case - we are either overwriting already
693,11 → 695,9
unsigned nclsts;
fat_cluster_t mcl, lcl;
nclsts = (ROUND_UP(pos + bytes, bps * spc) - boundary) /
bps * spc;
nclsts = (ROUND_UP(pos + bytes, bpc) - boundary) / bpc;
/* create an independent chain of nclsts clusters in all FATs */
status = fat_alloc_clusters(bs, dev_handle, nclsts, &mcl,
&lcl);
status = fat_alloc_clusters(bs, dev_handle, nclsts, &mcl, &lcl);
if (status != EOK) {
/* could not allocate a chain of nclsts clusters */
fat_node_put(nodep);
731,6 → 731,10
fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
size_t size = (off_t)IPC_GET_ARG3(*request);
fat_node_t *nodep = (fat_node_t *)fat_node_get(dev_handle, index);
fat_bs_t *bs;
uint16_t bps;
uint8_t spc;
unsigned bpc; /* bytes per cluster */
int rc;
 
if (!nodep) {
738,24 → 742,45
return;
}
 
bs = block_bb_get(dev_handle);
bps = uint16_t_le2host(bs->bps);
spc = bs->spc;
bpc = bps * spc;
 
if (nodep->size == size) {
rc = EOK;
} else if (nodep->size < size) {
/*
* TODO: the standard says we have the freedom to grow the file.
* The standard says we have the freedom to grow the node.
* For now, we simply return an error.
*/
rc = EINVAL;
} else if (ROUND_UP(nodep->size, bpc) == ROUND_UP(size, bpc)) {
/*
* The node will be shrunk, but no clusters will be deallocated.
*/
nodep->size = size;
nodep->dirty = true; /* need to sync node */
rc = EOK;
} else {
/*
* The file is to be shrunk.
* The node will be shrunk, clusters will be deallocated.
*/
rc = ENOTSUP; /* XXX */
if (size == 0) {
fat_chop_clusters(bs, nodep, FAT_CLST_RES0);
} else {
fat_cluster_t lastc;
(void) fat_cluster_walk(bs, dev_handle, nodep->firstc,
&lastc, (size - 1) / bpc);
fat_chop_clusters(bs, nodep, lastc);
}
nodep->size = size;
nodep->dirty = true; /* need to sync node */
rc = EOK;
}
fat_node_put(nodep);
ipc_answer_0(rid, rc);
return;
 
}
 
/**