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Ignore whitespace Rev 3598 → Rev 3869

/branches/dynload/uspace/srv/fs/fat/fat_ops.c
94,10 → 94,14
d = ((fat_dentry_t *)b->data) + (node->idx->pdi % dps);
 
d->firstc = host2uint16_t_le(node->firstc);
if (node->type == FAT_FILE)
if (node->type == FAT_FILE) {
d->size = host2uint32_t_le(node->size);
/* TODO: update other fields? (e.g time fields, attr field) */
} else if (node->type == FAT_DIRECTORY) {
d->attr = FAT_ATTR_SUBDIR;
}
/* TODO: update other fields? (e.g time fields) */
b->dirty = true; /* need to sync block */
block_put(b);
}
216,8 → 220,31
return nodep;
}
 
/*
* Forward declarations of FAT libfs operations.
*/
static void *fat_node_get(dev_handle_t, fs_index_t);
static void fat_node_put(void *);
static void *fat_create_node(dev_handle_t, int);
static int fat_destroy_node(void *);
static int fat_link(void *, void *, const char *);
static int fat_unlink(void *, void *);
static void *fat_match(void *, const char *);
static fs_index_t fat_index_get(void *);
static size_t fat_size_get(void *);
static unsigned fat_lnkcnt_get(void *);
static bool fat_has_children(void *);
static void *fat_root_get(dev_handle_t);
static char fat_plb_get_char(unsigned);
static bool fat_is_directory(void *);
static bool fat_is_file(void *node);
 
/*
* FAT libfs operations.
*/
 
/** Instantiate a FAT in-core node. */
static void *fat_node_get(dev_handle_t dev_handle, fs_index_t index)
void *fat_node_get(dev_handle_t dev_handle, fs_index_t index)
{
void *node;
fat_idx_t *idxp;
231,40 → 258,297
return node;
}
 
static void fat_node_put(void *node)
void fat_node_put(void *node)
{
fat_node_t *nodep = (fat_node_t *)node;
bool destroy = false;
 
futex_down(&nodep->lock);
if (!--nodep->refcnt) {
futex_down(&ffn_futex);
list_append(&nodep->ffn_link, &ffn_head);
futex_up(&ffn_futex);
if (nodep->idx) {
futex_down(&ffn_futex);
list_append(&nodep->ffn_link, &ffn_head);
futex_up(&ffn_futex);
} else {
/*
* The node does not have any index structure associated
* with itself. This can only mean that we are releasing
* the node after a failed attempt to allocate the index
* structure for it.
*/
destroy = true;
}
}
futex_up(&nodep->lock);
if (destroy)
free(node);
}
 
static void *fat_create(dev_handle_t dev_handle, int flags)
void *fat_create_node(dev_handle_t dev_handle, int flags)
{
return NULL; /* not supported at the moment */
fat_idx_t *idxp;
fat_node_t *nodep;
fat_bs_t *bs;
fat_cluster_t mcl, lcl;
uint16_t bps;
int rc;
 
bs = block_bb_get(dev_handle);
bps = uint16_t_le2host(bs->bps);
if (flags & L_DIRECTORY) {
/* allocate a cluster */
rc = fat_alloc_clusters(bs, dev_handle, 1, &mcl, &lcl);
if (rc != EOK)
return NULL;
}
 
nodep = fat_node_get_new();
if (!nodep) {
fat_free_clusters(bs, dev_handle, mcl);
return NULL;
}
idxp = fat_idx_get_new(dev_handle);
if (!idxp) {
fat_free_clusters(bs, dev_handle, mcl);
fat_node_put(nodep);
return NULL;
}
/* idxp->lock held */
if (flags & L_DIRECTORY) {
int i;
block_t *b;
 
/*
* Populate the new cluster with unused dentries.
*/
for (i = 0; i < bs->spc; i++) {
b = _fat_block_get(bs, dev_handle, mcl, i,
BLOCK_FLAGS_NOREAD);
/* mark all dentries as never-used */
memset(b->data, 0, bps);
b->dirty = false;
block_put(b);
}
nodep->type = FAT_DIRECTORY;
nodep->firstc = mcl;
nodep->size = bps * bs->spc;
} else {
nodep->type = FAT_FILE;
nodep->firstc = FAT_CLST_RES0;
nodep->size = 0;
}
nodep->lnkcnt = 0; /* not linked anywhere */
nodep->refcnt = 1;
nodep->dirty = true;
 
nodep->idx = idxp;
idxp->nodep = nodep;
 
futex_up(&idxp->lock);
return nodep;
}
 
static int fat_destroy(void *node)
int fat_destroy_node(void *node)
{
return ENOTSUP; /* not supported at the moment */
fat_node_t *nodep = (fat_node_t *)node;
fat_bs_t *bs;
 
/*
* The node is not reachable from the file system. This means that the
* link count should be zero and that the index structure cannot be
* found in the position hash. Obviously, we don't need to lock the node
* nor its index structure.
*/
assert(nodep->lnkcnt == 0);
 
/*
* The node may not have any children.
*/
assert(fat_has_children(node) == false);
 
bs = block_bb_get(nodep->idx->dev_handle);
if (nodep->firstc != FAT_CLST_RES0) {
assert(nodep->size);
/* Free all clusters allocated to the node. */
fat_free_clusters(bs, nodep->idx->dev_handle, nodep->firstc);
}
 
fat_idx_destroy(nodep->idx);
free(nodep);
return EOK;
}
 
static bool fat_link(void *prnt, void *chld, const char *name)
int fat_link(void *prnt, void *chld, const char *name)
{
return false; /* not supported at the moment */
fat_node_t *parentp = (fat_node_t *)prnt;
fat_node_t *childp = (fat_node_t *)chld;
fat_dentry_t *d;
fat_bs_t *bs;
block_t *b;
int i, j;
uint16_t bps;
unsigned dps;
unsigned blocks;
 
futex_down(&childp->lock);
if (childp->lnkcnt == 1) {
/*
* On FAT, we don't support multiple hard links.
*/
futex_up(&childp->lock);
return EMLINK;
}
assert(childp->lnkcnt == 0);
futex_up(&childp->lock);
 
if (!fat_dentry_name_verify(name)) {
/*
* Attempt to create unsupported name.
*/
return ENOTSUP;
}
 
/*
* Get us an unused parent node's dentry or grow the parent and allocate
* a new one.
*/
futex_down(&parentp->idx->lock);
bs = block_bb_get(parentp->idx->dev_handle);
bps = uint16_t_le2host(bs->bps);
dps = bps / sizeof(fat_dentry_t);
 
blocks = parentp->size / bps;
 
for (i = 0; i < blocks; i++) {
b = fat_block_get(bs, parentp, i, BLOCK_FLAGS_NONE);
for (j = 0; j < dps; j++) {
d = ((fat_dentry_t *)b->data) + j;
switch (fat_classify_dentry(d)) {
case FAT_DENTRY_SKIP:
case FAT_DENTRY_VALID:
/* skipping used and meta entries */
continue;
case FAT_DENTRY_FREE:
case FAT_DENTRY_LAST:
/* found an empty slot */
goto hit;
}
}
block_put(b);
}
/*
* We need to grow the parent in order to create a new unused dentry.
*/
futex_up(&parentp->idx->lock);
return ENOTSUP; /* XXX */
 
hit:
/*
* At this point we only establish the link between the parent and the
* child. The dentry, except of the name and the extension, will remain
* uninitialized until the the corresponding node is synced. Thus the
* valid dentry data is kept in the child node structure.
*/
memset(d, 0, sizeof(fat_dentry_t));
fat_dentry_name_set(d, name);
b->dirty = true; /* need to sync block */
block_put(b);
futex_up(&parentp->idx->lock);
 
futex_down(&childp->idx->lock);
/*
* If possible, create the Sub-directory Identifier Entry and the
* Sub-directory Parent Pointer Entry (i.e. "." and ".."). These entries
* are not mandatory according to Standard ECMA-107 and HelenOS VFS does
* not use them anyway, so this is rather a sign of our good will.
*/
b = fat_block_get(bs, childp, 0, BLOCK_FLAGS_NONE);
d = (fat_dentry_t *)b->data;
if (fat_classify_dentry(d) == FAT_DENTRY_LAST ||
strcmp(d->name, FAT_NAME_DOT) == 0) {
memset(d, 0, sizeof(fat_dentry_t));
strcpy(d->name, FAT_NAME_DOT);
strcpy(d->ext, FAT_EXT_PAD);
d->attr = FAT_ATTR_SUBDIR;
d->firstc = host2uint16_t_le(childp->firstc);
/* TODO: initialize also the date/time members. */
}
d++;
if (fat_classify_dentry(d) == FAT_DENTRY_LAST ||
strcmp(d->name, FAT_NAME_DOT_DOT) == 0) {
memset(d, 0, sizeof(fat_dentry_t));
strcpy(d->name, FAT_NAME_DOT_DOT);
strcpy(d->ext, FAT_EXT_PAD);
d->attr = FAT_ATTR_SUBDIR;
d->firstc = (parentp->firstc == FAT_CLST_ROOT) ?
host2uint16_t_le(FAT_CLST_RES0) :
host2uint16_t_le(parentp->firstc);
/* TODO: initialize also the date/time members. */
}
b->dirty = true; /* need to sync block */
block_put(b);
 
childp->idx->pfc = parentp->firstc;
childp->idx->pdi = i * dps + j;
futex_up(&childp->idx->lock);
 
futex_down(&childp->lock);
childp->lnkcnt = 1;
childp->dirty = true; /* need to sync node */
futex_up(&childp->lock);
 
/*
* Hash in the index structure into the position hash.
*/
fat_idx_hashin(childp->idx);
 
return EOK;
}
 
static int fat_unlink(void *prnt, void *chld)
int fat_unlink(void *prnt, void *chld)
{
return ENOTSUP; /* not supported at the moment */
fat_node_t *parentp = (fat_node_t *)prnt;
fat_node_t *childp = (fat_node_t *)chld;
fat_bs_t *bs;
fat_dentry_t *d;
uint16_t bps;
block_t *b;
 
futex_down(&parentp->lock);
futex_down(&childp->lock);
assert(childp->lnkcnt == 1);
futex_down(&childp->idx->lock);
bs = block_bb_get(childp->idx->dev_handle);
bps = uint16_t_le2host(bs->bps);
 
b = _fat_block_get(bs, childp->idx->dev_handle, childp->idx->pfc,
(childp->idx->pdi * sizeof(fat_dentry_t)) / bps,
BLOCK_FLAGS_NONE);
d = (fat_dentry_t *)b->data +
(childp->idx->pdi % (bps / sizeof(fat_dentry_t)));
/* mark the dentry as not-currently-used */
d->name[0] = FAT_DENTRY_ERASED;
b->dirty = true; /* need to sync block */
block_put(b);
 
/* remove the index structure from the position hash */
fat_idx_hashout(childp->idx);
/* clear position information */
childp->idx->pfc = FAT_CLST_RES0;
childp->idx->pdi = 0;
futex_up(&childp->idx->lock);
childp->lnkcnt = 0;
childp->dirty = true;
futex_up(&childp->lock);
futex_up(&parentp->lock);
 
return EOK;
}
 
static void *fat_match(void *prnt, const char *component)
void *fat_match(void *prnt, const char *component)
{
fat_bs_t *bs;
fat_node_t *parentp = (fat_node_t *)prnt;
287,6 → 571,7
d = ((fat_dentry_t *)b->data) + j;
switch (fat_classify_dentry(d)) {
case FAT_DENTRY_SKIP:
case FAT_DENTRY_FREE:
continue;
case FAT_DENTRY_LAST:
block_put(b);
294,10 → 579,10
return NULL;
default:
case FAT_DENTRY_VALID:
dentry_name_canonify(d, name);
fat_dentry_name_get(d, name);
break;
}
if (stricmp(name, component) == 0) {
if (fat_dentry_namecmp(name, component) == 0) {
/* hit */
void *node;
/*
331,7 → 616,7
return NULL;
}
 
static fs_index_t fat_index_get(void *node)
fs_index_t fat_index_get(void *node)
{
fat_node_t *fnodep = (fat_node_t *)node;
if (!fnodep)
339,17 → 624,17
return fnodep->idx->index;
}
 
static size_t fat_size_get(void *node)
size_t fat_size_get(void *node)
{
return ((fat_node_t *)node)->size;
}
 
static unsigned fat_lnkcnt_get(void *node)
unsigned fat_lnkcnt_get(void *node)
{
return ((fat_node_t *)node)->lnkcnt;
}
 
static bool fat_has_children(void *node)
bool fat_has_children(void *node)
{
fat_bs_t *bs;
fat_node_t *nodep = (fat_node_t *)node;
377,6 → 662,7
d = ((fat_dentry_t *)b->data) + j;
switch (fat_classify_dentry(d)) {
case FAT_DENTRY_SKIP:
case FAT_DENTRY_FREE:
continue;
case FAT_DENTRY_LAST:
block_put(b);
399,22 → 685,22
return false;
}
 
static void *fat_root_get(dev_handle_t dev_handle)
void *fat_root_get(dev_handle_t dev_handle)
{
return fat_node_get(dev_handle, 0);
}
 
static char fat_plb_get_char(unsigned pos)
char fat_plb_get_char(unsigned pos)
{
return fat_reg.plb_ro[pos % PLB_SIZE];
}
 
static bool fat_is_directory(void *node)
bool fat_is_directory(void *node)
{
return ((fat_node_t *)node)->type == FAT_DIRECTORY;
}
 
static bool fat_is_file(void *node)
bool fat_is_file(void *node)
{
return ((fat_node_t *)node)->type == FAT_FILE;
}
424,8 → 710,8
.match = fat_match,
.node_get = fat_node_get,
.node_put = fat_node_put,
.create = fat_create,
.destroy = fat_destroy,
.create = fat_create_node,
.destroy = fat_destroy_node,
.link = fat_link,
.unlink = fat_unlink,
.index_get = fat_index_get,
438,6 → 724,10
.is_file = fat_is_file
};
 
/*
* VFS operations.
*/
 
void fat_mounted(ipc_callid_t rid, ipc_call_t *request)
{
dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
607,6 → 897,7
d = ((fat_dentry_t *)b->data) + o;
switch (fat_classify_dentry(d)) {
case FAT_DENTRY_SKIP:
case FAT_DENTRY_FREE:
continue;
case FAT_DENTRY_LAST:
block_put(b);
613,7 → 904,7
goto miss;
default:
case FAT_DENTRY_VALID:
dentry_name_canonify(d, name);
fat_dentry_name_get(d, name);
block_put(b);
goto hit;
}
799,6 → 1090,22
return;
}
 
void fat_destroy(ipc_callid_t rid, ipc_call_t *request)
{
dev_handle_t dev_handle = (dev_handle_t)IPC_GET_ARG1(*request);
fs_index_t index = (fs_index_t)IPC_GET_ARG2(*request);
int rc;
 
fat_node_t *nodep = fat_node_get(dev_handle, index);
if (!nodep) {
ipc_answer_0(rid, ENOENT);
return;
}
 
rc = fat_destroy_node(nodep);
ipc_answer_0(rid, rc);
}
 
/**
* @}
*/