/branches/tracing/uspace/srv/fs/tmpfs/tmpfs_ops.c |
---|
69,12 → 69,13 |
*/ |
/* Forward declarations of static functions. */ |
static bool tmpfs_match(void *, void *, const char *); |
static void *tmpfs_node_get(fs_handle_t, dev_handle_t, fs_index_t); |
static void *tmpfs_match(void *, const char *); |
static void *tmpfs_node_get(dev_handle_t, fs_index_t); |
static void tmpfs_node_put(void *); |
static void *tmpfs_create_node(int); |
static bool tmpfs_link_node(void *, void *, const char *); |
static int tmpfs_unlink_node(void *, void *); |
static void tmpfs_destroy_node(void *); |
static int tmpfs_destroy_node(void *); |
/* Implementation of helper functions. */ |
static fs_index_t tmpfs_index_get(void *nodep) |
92,18 → 93,13 |
return ((tmpfs_dentry_t *) nodep)->lnkcnt; |
} |
static void *tmpfs_child_get(void *nodep) |
static bool tmpfs_has_children(void *nodep) |
{ |
return ((tmpfs_dentry_t *) nodep)->child; |
return ((tmpfs_dentry_t *) nodep)->child != NULL; |
} |
static void *tmpfs_sibling_get(void *nodep) |
static void *tmpfs_root_get(dev_handle_t dev_handle) |
{ |
return ((tmpfs_dentry_t *) nodep)->sibling; |
} |
static void *tmpfs_root_get(void) |
{ |
return root; |
} |
126,6 → 122,7 |
libfs_ops_t tmpfs_libfs_ops = { |
.match = tmpfs_match, |
.node_get = tmpfs_node_get, |
.node_put = tmpfs_node_put, |
.create = tmpfs_create_node, |
.destroy = tmpfs_destroy_node, |
.link = tmpfs_link_node, |
133,8 → 130,7 |
.index_get = tmpfs_index_get, |
.size_get = tmpfs_size_get, |
.lnkcnt_get = tmpfs_lnkcnt_get, |
.child_get = tmpfs_child_get, |
.sibling_get = tmpfs_sibling_get, |
.has_children = tmpfs_has_children, |
.root_get = tmpfs_root_get, |
.plb_get_char = tmpfs_plb_get_char, |
.is_directory = tmpfs_is_directory, |
243,27 → 239,36 |
/** Compare one component of path to a directory entry. |
* |
* @param prnt Node from which we descended. |
* @param chld Node to compare the path component with. |
* @param parentp Pointer to node from which we descended. |
* @param childp Pointer to node to compare the path component with. |
* @param component Array of characters holding component name. |
* |
* @return True on match, false otherwise. |
*/ |
bool tmpfs_match(void *prnt, void *chld, const char *component) |
static bool |
tmpfs_match_one(tmpfs_dentry_t *parentp, tmpfs_dentry_t *childp, |
const char *component) |
{ |
tmpfs_dentry_t *parentp = (tmpfs_dentry_t *) prnt; |
tmpfs_dentry_t *childp = (tmpfs_dentry_t *) chld; |
unsigned long key = (unsigned long) parentp; |
link_t *hlp = hash_table_find(&childp->names, &key); |
assert(hlp); |
tmpfs_name_t *namep = hash_table_get_instance(hlp, tmpfs_name_t, link); |
return !strcmp(namep->name, component); |
} |
void *tmpfs_match(void *prnt, const char *component) |
{ |
tmpfs_dentry_t *parentp = (tmpfs_dentry_t *) prnt; |
tmpfs_dentry_t *childp = parentp->child; |
while (childp && !tmpfs_match_one(parentp, childp, component)) |
childp = childp->sibling; |
return (void *) childp; |
} |
void * |
tmpfs_node_get(fs_handle_t fs_handle, dev_handle_t dev_handle, fs_index_t index) |
tmpfs_node_get(dev_handle_t dev_handle, fs_index_t index) |
{ |
unsigned long key = index; |
link_t *lnk = hash_table_find(&dentries, &key); |
272,6 → 277,11 |
return hash_table_get_instance(lnk, tmpfs_dentry_t, dh_link); |
} |
void tmpfs_node_put(void *node) |
{ |
/* nothing to do */ |
} |
void *tmpfs_create_node(int lflag) |
{ |
assert((lflag & L_FILE) ^ (lflag & L_DIRECTORY)); |
364,7 → 374,7 |
return EOK; |
} |
void tmpfs_destroy_node(void *nodep) |
int tmpfs_destroy_node(void *nodep) |
{ |
tmpfs_dentry_t *dentry = (tmpfs_dentry_t *) nodep; |
380,6 → 390,7 |
if (dentry->type == TMPFS_FILE) |
free(dentry->data); |
free(dentry); |
return EOK; |
} |
void tmpfs_lookup(ipc_callid_t rid, ipc_call_t *request) |
568,6 → 579,7 |
{ |
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; |
link_t *hlp; |
unsigned long key = index; |
578,8 → 590,8 |
} |
tmpfs_dentry_t *dentry = hash_table_get_instance(hlp, tmpfs_dentry_t, |
dh_link); |
tmpfs_destroy_node(dentry); |
ipc_answer_0(rid, EOK); |
rc = tmpfs_destroy_node(dentry); |
ipc_answer_0(rid, rc); |
} |
/** |
/branches/tracing/uspace/srv/fs/fat/fat_idx.c |
---|
0,0 → 1,377 |
/* |
* Copyright (c) 2008 Jakub Jermar |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - Redistributions in binary form must reproduce the above copyright |
* notice, this list of conditions and the following disclaimer in the |
* documentation and/or other materials provided with the distribution. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
*/ |
/** @addtogroup fs |
* @{ |
*/ |
/** |
* @file fat_idx.c |
* @brief Layer for translating FAT entities to VFS node indices. |
*/ |
#include "fat.h" |
#include "../../vfs/vfs.h" |
#include <errno.h> |
#include <string.h> |
#include <libadt/hash_table.h> |
#include <libadt/list.h> |
#include <assert.h> |
#include <futex.h> |
/** Each instance of this type describes one interval of freed VFS indices. */ |
typedef struct { |
link_t link; |
fs_index_t first; |
fs_index_t last; |
} freed_t; |
/** |
* Each instance of this type describes state of all VFS indices that |
* are currently unused. |
*/ |
typedef struct { |
link_t link; |
dev_handle_t dev_handle; |
/** Next unassigned index. */ |
fs_index_t next; |
/** Number of remaining unassigned indices. */ |
uint64_t remaining; |
/** Sorted list of intervals of freed indices. */ |
link_t freed_head; |
} unused_t; |
static LIST_INITIALIZE(unused_head); |
/** |
* Global hash table of all used fat_idx_t structures. |
* The index structures are hashed by the dev_handle, parent node's first |
* cluster and index within the parent directory. |
*/ |
static hash_table_t up_hash; |
#define UPH_BUCKETS_LOG 12 |
#define UPH_BUCKETS (1 << UPH_BUCKETS_LOG) |
#define UPH_DH_KEY 0 |
#define UPH_PFC_KEY 1 |
#define UPH_PDI_KEY 2 |
static hash_index_t pos_hash(unsigned long key[]) |
{ |
dev_handle_t dev_handle = (dev_handle_t)key[UPH_DH_KEY]; |
fat_cluster_t pfc = (fat_cluster_t)key[UPH_PFC_KEY]; |
unsigned pdi = (unsigned)key[UPH_PDI_KEY]; |
hash_index_t h; |
/* |
* The least significant half of all bits are the least significant bits |
* of the parent node's first cluster. |
* |
* The least significant half of the most significant half of all bits |
* are the least significant bits of the node's dentry index within the |
* parent directory node. |
* |
* The most significant half of the most significant half of all bits |
* are the least significant bits of the device handle. |
*/ |
h = pfc & ((1 << (UPH_BUCKETS_LOG / 2)) - 1); |
h |= (pdi & ((1 << (UPH_BUCKETS_LOG / 4)) - 1)) << |
(UPH_BUCKETS_LOG / 2); |
h |= (dev_handle & ((1 << (UPH_BUCKETS_LOG / 4)) - 1)) << |
(3 * (UPH_BUCKETS_LOG / 4)); |
return h; |
} |
static int pos_compare(unsigned long key[], hash_count_t keys, link_t *item) |
{ |
dev_handle_t dev_handle = (dev_handle_t)key[UPH_DH_KEY]; |
fat_cluster_t pfc = (fat_cluster_t)key[UPH_PFC_KEY]; |
unsigned pdi = (unsigned)key[UPH_PDI_KEY]; |
fat_idx_t *fidx = list_get_instance(item, fat_idx_t, uph_link); |
return (dev_handle == fidx->dev_handle) && (pfc == fidx->pfc) && |
(pdi == fidx->pdi); |
} |
static void pos_remove_callback(link_t *item) |
{ |
/* nothing to do */ |
} |
static hash_table_operations_t uph_ops = { |
.hash = pos_hash, |
.compare = pos_compare, |
.remove_callback = pos_remove_callback, |
}; |
/** |
* Global hash table of all used fat_idx_t structures. |
* The index structures are hashed by the dev_handle and index. |
*/ |
static hash_table_t ui_hash; |
#define UIH_BUCKETS_LOG 12 |
#define UIH_BUCKETS (1 << UIH_BUCKETS_LOG) |
#define UIH_DH_KEY 0 |
#define UIH_INDEX_KEY 1 |
static hash_index_t idx_hash(unsigned long key[]) |
{ |
dev_handle_t dev_handle = (dev_handle_t)key[UIH_DH_KEY]; |
fs_index_t index = (fs_index_t)key[UIH_INDEX_KEY]; |
hash_index_t h; |
h = dev_handle & ((1 << (UIH_BUCKETS_LOG / 2)) - 1); |
h |= (index & ((1 << (UIH_BUCKETS_LOG / 2)) - 1)) << |
(UIH_BUCKETS_LOG / 2); |
return h; |
} |
static int idx_compare(unsigned long key[], hash_count_t keys, link_t *item) |
{ |
dev_handle_t dev_handle = (dev_handle_t)key[UIH_DH_KEY]; |
fs_index_t index = (fs_index_t)key[UIH_INDEX_KEY]; |
fat_idx_t *fidx = list_get_instance(item, fat_idx_t, uih_link); |
return (dev_handle == fidx->dev_handle) && (index == fidx->index); |
} |
static void idx_remove_callback(link_t *item) |
{ |
/* nothing to do */ |
} |
static hash_table_operations_t uih_ops = { |
.hash = idx_hash, |
.compare = idx_compare, |
.remove_callback = idx_remove_callback, |
}; |
/** Allocate a VFS index which is not currently in use. */ |
static bool fat_idx_alloc(dev_handle_t dev_handle, fs_index_t *index) |
{ |
link_t *l; |
unused_t *u; |
assert(index); |
for (l = unused_head.next; l != &unused_head; l = l->next) { |
u = list_get_instance(l, unused_t, link); |
if (u->dev_handle == dev_handle) |
goto hit; |
} |
/* dev_handle not found */ |
return false; |
hit: |
if (list_empty(&u->freed_head)) { |
if (u->remaining) { |
/* |
* There are no freed indices, allocate one directly |
* from the counter. |
*/ |
*index = u->next++; |
--u->remaining; |
return true; |
} |
} else { |
/* There are some freed indices which we can reuse. */ |
freed_t *f = list_get_instance(u->freed_head.next, freed_t, |
link); |
*index = f->first; |
if (f->first++ == f->last) { |
/* Destroy the interval. */ |
list_remove(&f->link); |
free(f); |
} |
return true; |
} |
/* |
* We ran out of indices, which is extremely unlikely with FAT16, but |
* theoretically still possible (e.g. too many open unlinked nodes or |
* too many zero-sized nodes). |
*/ |
return false; |
} |
/** If possible, coalesce two intervals of freed indices. */ |
static void try_coalesce_intervals(link_t *l, link_t *r, link_t *cur) |
{ |
freed_t *fl = list_get_instance(l, freed_t, link); |
freed_t *fr = list_get_instance(r, freed_t, link); |
if (fl->last + 1 == fr->first) { |
if (cur == l) { |
fl->last = fr->last; |
list_remove(r); |
free(r); |
} else { |
fr->first = fl->first; |
list_remove(l); |
free(l); |
} |
} |
} |
/** Free a VFS index, which is no longer in use. */ |
static void fat_idx_free(dev_handle_t dev_handle, fs_index_t index) |
{ |
link_t *l; |
unused_t *u; |
for (l = unused_head.next; l != &unused_head; l = l->next) { |
u = list_get_instance(l, unused_t, link); |
if (u->dev_handle == dev_handle) |
goto hit; |
} |
/* should not happen */ |
assert(0); |
hit: |
if (u->next == index + 1) { |
/* The index can be returned directly to the counter. */ |
u->next--; |
u->remaining++; |
return; |
} else { |
/* |
* The index must be returned either to an existing freed |
* interval or a new interval must be created. |
*/ |
link_t *lnk; |
freed_t *n; |
for (lnk = u->freed_head.next; lnk != &u->freed_head; |
lnk = lnk->next) { |
freed_t *f = list_get_instance(lnk, freed_t, link); |
if (f->first == index + 1) { |
f->first--; |
if (lnk->prev != &u->freed_head) |
try_coalesce_intervals(lnk->prev, lnk, |
lnk); |
return; |
} |
if (f->last == index - 1) { |
f->last++; |
if (lnk->next != &u->freed_head) |
try_coalesce_intervals(lnk, lnk->next, |
lnk); |
return; |
} |
if (index > f->first) { |
n = malloc(sizeof(freed_t)); |
/* TODO: sleep until allocation succeeds */ |
assert(n); |
link_initialize(&n->link); |
n->first = index; |
n->last = index; |
list_insert_before(&n->link, lnk); |
return; |
} |
} |
/* The index will form the last interval. */ |
n = malloc(sizeof(freed_t)); |
/* TODO: sleep until allocation succeeds */ |
assert(n); |
link_initialize(&n->link); |
n->first = index; |
n->last = index; |
list_append(&n->link, &u->freed_head); |
} |
} |
fat_idx_t * |
fat_idx_get_by_pos(dev_handle_t dev_handle, fat_cluster_t pfc, unsigned pdi) |
{ |
fat_idx_t *fidx; |
link_t *l; |
unsigned long pkey[] = { |
[UPH_DH_KEY] = dev_handle, |
[UPH_PFC_KEY] = pfc, |
[UPH_PDI_KEY] = pdi, |
}; |
l = hash_table_find(&up_hash, pkey); |
if (l) { |
fidx = hash_table_get_instance(l, fat_idx_t, uph_link); |
} else { |
fidx = (fat_idx_t *) malloc(sizeof(fat_idx_t)); |
if (!fidx) { |
return NULL; |
} |
if (!fat_idx_alloc(dev_handle, &fidx->index)) { |
free(fidx); |
return NULL; |
} |
unsigned long ikey[] = { |
[UIH_DH_KEY] = dev_handle, |
[UIH_INDEX_KEY] = fidx->index, |
}; |
link_initialize(&fidx->uph_link); |
link_initialize(&fidx->uih_link); |
fidx->dev_handle = dev_handle; |
fidx->pfc = pfc; |
fidx->pdi = pdi; |
fidx->nodep = NULL; |
hash_table_insert(&up_hash, pkey, &fidx->uph_link); |
hash_table_insert(&ui_hash, ikey, &fidx->uih_link); |
} |
return fidx; |
} |
fat_idx_t * |
fat_idx_get_by_index(dev_handle_t dev_handle, fs_index_t index) |
{ |
fat_idx_t *fidx = NULL; |
link_t *l; |
unsigned long ikey[] = { |
[UIH_DH_KEY] = dev_handle, |
[UIH_INDEX_KEY] = index, |
}; |
l = hash_table_find(&ui_hash, ikey); |
if (l) { |
fidx = hash_table_get_instance(l, fat_idx_t, uih_link); |
} |
return fidx; |
} |
/branches/tracing/uspace/srv/fs/fat/fat.h |
---|
1,5 → 1,5 |
/* |
* Copyright (c) 2007 Jakub Jermar |
* Copyright (c) 2008 Jakub Jermar |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
38,6 → 38,7 |
#include <atomic.h> |
#include <sys/types.h> |
#include <bool.h> |
#include "../../vfs/vfs.h" |
#define dprintf(...) printf(__VA_ARGS__) |
47,17 → 48,17 |
/* BIOS Parameter Block */ |
uint16_t bps; /**< Bytes per sector. */ |
uint8_t spc; /**< Sectors per cluster. */ |
uint16_t rsc; /**< Reserved sector count. */ |
uint16_t rscnt; /**< Reserved sector count. */ |
uint8_t fatcnt; /**< Number of FATs. */ |
uint16_t root_ent_max; /**< Maximum number of root directory |
entries. */ |
uint16_t totsec; /**< Total sectors. */ |
uint16_t totsec16; /**< Total sectors. 16-bit version. */ |
uint8_t mdesc; /**< Media descriptor. */ |
uint16_t sec_per_fat; /**< Sectors per FAT12/FAT16. */ |
uint16_t sec_per_track; /**< Sectors per track. */ |
uint16_t headcnt; /**< Number of heads. */ |
uint32_t hidden_sec; /**< Hidden sectors. */ |
uint32_t total_sec; /**< Total sectors. */ |
uint32_t totsec32; /**< Total sectors. 32-bit version. */ |
union { |
struct { |
101,7 → 102,7 |
/** Serial number. */ |
uint32_t id; |
/** Volume label. */ |
uint8_t label; |
uint8_t label[11]; |
/** FAT type. */ |
uint8_t type[8]; |
/** Boot code. */ |
112,6 → 113,10 |
}; |
} __attribute__ ((packed)) fat_bs_t; |
#define FAT_ATTR_RDONLY (1 << 0) |
#define FAT_ATTR_VOLLABEL (1 << 3) |
#define FAT_ATTR_SUBDIR (1 << 4) |
typedef struct { |
uint8_t name[8]; |
uint8_t ext[3]; |
134,10 → 139,87 |
uint32_t size; |
} __attribute__ ((packed)) fat_dentry_t; |
typedef uint16_t fat_cluster_t; |
typedef enum { |
FAT_INVALID, |
FAT_DIRECTORY, |
FAT_FILE |
} fat_node_type_t; |
struct fat_node; |
/** FAT index structure. |
* |
* This structure exists to help us to overcome certain limitations of the FAT |
* file system design. The problem with FAT is that it is hard to find |
* an entity which could represent a VFS index. There are two candidates: |
* |
* a) number of the node's first cluster |
* b) the pair of the parent directory's first cluster and the dentry index |
* within the parent directory |
* |
* We need VFS indices to be: |
* A) unique |
* B) stable in time, at least until the next mount |
* |
* Unfortunately a) does not meet the A) criterion because zero-length files |
* will have the first cluster field cleared. And b) does not meet the B) |
* criterion because unlink() and rename() will both free up the original |
* dentry, which contains all the essential info about the file. |
* |
* Therefore, a completely opaque indices are used and the FAT server maintains |
* a mapping between them and otherwise nice b) variant. On rename(), the VFS |
* index stays unaltered, while the internal FAT "physical tree address" |
* changes. The unlink case is also handled this way thanks to an in-core node |
* pointer embedded in the index structure. |
*/ |
typedef struct { |
/** Used indices (position) hash table link. */ |
link_t uph_link; |
/** Used indices (index) hash table link. */ |
link_t uih_link; |
dev_handle_t dev_handle; |
fs_index_t index; |
/** |
* Parent node's first cluster. |
* Zero is used if this node is not linked, in which case nodep must |
* contain a pointer to the in-core node structure. |
* One is used when the parent is the root directory. |
*/ |
fat_cluster_t pfc; |
/** Directory entry index within the parent node. */ |
unsigned pdi; |
/** Pointer to in-core node instance. */ |
struct fat_node *nodep; |
} fat_idx_t; |
/** FAT in-core node. */ |
typedef struct fat_node { |
fat_node_type_t type; |
fat_idx_t *idx; |
/** |
* Node's first cluster. |
* Zero is used for zero-length nodes. |
* One is used to mark root directory. |
*/ |
fat_cluster_t firstc; |
/** FAT in-core node free list link. */ |
link_t ffn_link; |
size_t size; |
unsigned lnkcnt; |
unsigned refcnt; |
bool dirty; |
} fat_node_t; |
extern fs_reg_t fat_reg; |
extern void fat_lookup(ipc_callid_t, ipc_call_t *); |
extern fat_idx_t *fat_idx_get_by_pos(dev_handle_t, fat_cluster_t, unsigned); |
extern fat_idx_t *fat_idx_get_by_index(dev_handle_t, fs_index_t); |
#endif |
/** |
/branches/tracing/uspace/srv/fs/fat/fat_ops.c |
---|
1,5 → 1,5 |
/* |
* Copyright (c) 2007 Jakub Jermar |
* Copyright (c) 2008 Jakub Jermar |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
37,12 → 37,22 |
#include "fat.h" |
#include "../../vfs/vfs.h" |
#include <libfs.h> |
#include <ipc/ipc.h> |
#include <async.h> |
#include <errno.h> |
#include <string.h> |
#include <byteorder.h> |
#include <libadt/hash_table.h> |
#include <libadt/list.h> |
#include <assert.h> |
#include <futex.h> |
#define PLB_GET_CHAR(i) (fat_reg.plb_ro[(i) % PLB_SIZE]) |
#define BS_BLOCK 0 |
/** List of free FAT nodes that still contain valid data. */ |
LIST_INITIALIZE(ffn_head); |
#define FAT_NAME_LEN 8 |
#define FAT_EXT_LEN 3 |
53,90 → 63,454 |
#define FAT_DENTRY_DOT 0x2e |
#define FAT_DENTRY_ERASED 0xe5 |
/** Compare one component of path to a directory entry. |
* |
* @param dentry Directory entry to compare the path component with. |
* @param start Index into PLB where the path component starts. |
* @param last Index of the last character of the path in PLB. |
* |
* @return Zero on failure or delta such that (index + delta) % |
* PLB_SIZE points to a new path component in PLB. |
static void dentry_name_canonify(fat_dentry_t *d, char *buf) |
{ |
int i; |
for (i = 0; i < FAT_NAME_LEN; i++) { |
if (d->name[i] == FAT_PAD) { |
buf++; |
break; |
} |
if (d->name[i] == FAT_DENTRY_E5_ESC) |
*buf++ = 0xe5; |
else |
*buf++ = d->name[i]; |
} |
if (d->ext[0] != FAT_PAD) |
*buf++ = '.'; |
for (i = 0; i < FAT_EXT_LEN; i++) { |
if (d->ext[i] == FAT_PAD) { |
*buf = '\0'; |
return; |
} |
if (d->ext[i] == FAT_DENTRY_E5_ESC) |
*buf++ = 0xe5; |
else |
*buf++ = d->ext[i]; |
} |
} |
/* TODO move somewhere else */ |
typedef struct { |
void *data; |
} block_t; |
static block_t *block_get(dev_handle_t dev_handle, off_t offset) |
{ |
return NULL; /* TODO */ |
} |
static void block_put(block_t *block) |
{ |
/* TODO */ |
} |
#define FAT_BS(b) ((fat_bs_t *)((b)->data)) |
#define FAT_CLST_RES0 0x0000 |
#define FAT_CLST_RES1 0x0001 /* internally used to mark root directory */ |
#define FAT_CLST_FIRST 0x0002 |
#define FAT_CLST_BAD 0xfff7 |
#define FAT_CLST_LAST1 0xfff8 |
#define FAT_CLST_LAST8 0xffff |
#define fat_block_get(np, off) \ |
_fat_block_get((np)->idx->dev_handle, (np)->firstc, (off)) |
static block_t * |
_fat_block_get(dev_handle_t dev_handle, fat_cluster_t firstc, off_t offset) |
{ |
block_t *bb; |
block_t *b; |
unsigned bps; |
unsigned spc; |
unsigned rscnt; /* block address of the first FAT */ |
unsigned fatcnt; |
unsigned rde; |
unsigned rds; /* root directory size */ |
unsigned sf; |
unsigned ssa; /* size of the system area */ |
unsigned clusters; |
fat_cluster_t clst = firstc; |
unsigned i; |
bb = block_get(dev_handle, BS_BLOCK); |
bps = uint16_t_le2host(FAT_BS(bb)->bps); |
spc = FAT_BS(bb)->spc; |
rscnt = uint16_t_le2host(FAT_BS(bb)->rscnt); |
fatcnt = FAT_BS(bb)->fatcnt; |
rde = uint16_t_le2host(FAT_BS(bb)->root_ent_max); |
sf = uint16_t_le2host(FAT_BS(bb)->sec_per_fat); |
block_put(bb); |
rds = (sizeof(fat_dentry_t) * rde) / bps; |
rds += ((sizeof(fat_dentry_t) * rde) % bps != 0); |
ssa = rscnt + fatcnt * sf + rds; |
if (firstc == FAT_CLST_RES1) { |
/* root directory special case */ |
assert(offset < rds); |
b = block_get(dev_handle, rscnt + fatcnt * sf + offset); |
return b; |
} |
clusters = offset / spc; |
for (i = 0; i < clusters; i++) { |
unsigned fsec; /* sector offset relative to FAT1 */ |
unsigned fidx; /* FAT1 entry index */ |
assert(clst >= FAT_CLST_FIRST && clst < FAT_CLST_BAD); |
fsec = (clst * sizeof(fat_cluster_t)) / bps; |
fidx = clst % (bps / sizeof(fat_cluster_t)); |
/* read FAT1 */ |
b = block_get(dev_handle, rscnt + fsec); |
clst = uint16_t_le2host(((fat_cluster_t *)b->data)[fidx]); |
assert(clst != FAT_CLST_BAD); |
assert(clst < FAT_CLST_LAST1); |
block_put(b); |
} |
b = block_get(dev_handle, ssa + (clst - FAT_CLST_FIRST) * spc + |
offset % spc); |
return b; |
} |
static void fat_node_initialize(fat_node_t *node) |
{ |
node->idx = NULL; |
node->type = 0; |
link_initialize(&node->ffn_link); |
node->size = 0; |
node->lnkcnt = 0; |
node->refcnt = 0; |
node->dirty = false; |
} |
static uint16_t fat_bps_get(dev_handle_t dev_handle) |
{ |
block_t *bb; |
uint16_t bps; |
bb = block_get(dev_handle, BS_BLOCK); |
assert(bb != NULL); |
bps = uint16_t_le2host(FAT_BS(bb)->bps); |
block_put(bb); |
return bps; |
} |
typedef enum { |
FAT_DENTRY_SKIP, |
FAT_DENTRY_LAST, |
FAT_DENTRY_VALID |
} fat_dentry_clsf_t; |
static fat_dentry_clsf_t fat_classify_dentry(fat_dentry_t *d) |
{ |
if (d->attr & FAT_ATTR_VOLLABEL) { |
/* volume label entry */ |
return FAT_DENTRY_SKIP; |
} |
if (d->name[0] == FAT_DENTRY_ERASED) { |
/* not-currently-used entry */ |
return FAT_DENTRY_SKIP; |
} |
if (d->name[0] == FAT_DENTRY_UNUSED) { |
/* never used entry */ |
return FAT_DENTRY_LAST; |
} |
if (d->name[0] == FAT_DENTRY_DOT) { |
/* |
* Most likely '.' or '..'. |
* It cannot occur in a regular file name. |
*/ |
static unsigned match_path_component(fat_dentry_t *dentry, unsigned start, |
unsigned last) |
return FAT_DENTRY_SKIP; |
} |
return FAT_DENTRY_VALID; |
} |
static void fat_node_sync(fat_node_t *node) |
{ |
unsigned cur; /* current position in PLB */ |
int pos; /* current position in dentry->name or dentry->ext */ |
bool name_processed = false; |
bool dot_processed = false; |
bool ext_processed = false; |
/* TODO */ |
} |
if (last < start) |
last += PLB_SIZE; |
for (pos = 0, cur = start; (cur <= last) && (PLB_GET_CHAR(cur) != '/'); |
pos++, cur++) { |
if (!name_processed) { |
if ((pos == FAT_NAME_LEN - 1) || |
(dentry->name[pos + 1] == FAT_PAD)) { |
/* this is the last character in name */ |
name_processed = true; |
/** Instantiate a FAT in-core node. */ |
static void *fat_node_get(dev_handle_t dev_handle, fs_index_t index) |
{ |
fat_idx_t *idx; |
block_t *b; |
fat_dentry_t *d; |
fat_node_t *nodep; |
unsigned bps; |
unsigned dps; |
idx = fat_idx_get_by_index(dev_handle, index); |
if (!idx) |
return NULL; |
if (idx->nodep) { |
/* |
* We are lucky. |
* The node is already instantiated in memory. |
*/ |
if (!idx->nodep->refcnt++) |
list_remove(&nodep->ffn_link); |
return idx->nodep; |
} |
if (dentry->name[0] == FAT_PAD) { |
/* name is empty */ |
name_processed = true; |
} else if ((pos == 0) && (dentry->name[pos] == |
FAT_DENTRY_E5_ESC)) { |
if (PLB_GET_CHAR(cur) == 0xe5) |
continue; |
else |
return 0; /* character mismatch */ |
/* |
* We must instantiate the node from the file system. |
*/ |
assert(idx->pfc); |
if (!list_empty(&ffn_head)) { |
/* Try to use a cached unused node structure. */ |
nodep = list_get_instance(ffn_head.next, fat_node_t, ffn_link); |
if (nodep->dirty) |
fat_node_sync(nodep); |
list_remove(&nodep->ffn_link); |
nodep->idx->nodep = NULL; |
} else { |
if (PLB_GET_CHAR(cur) == dentry->name[pos]) |
/* Try to allocate a new node structure. */ |
nodep = (fat_node_t *)malloc(sizeof(fat_node_t)); |
if (!nodep) |
return NULL; |
} |
fat_node_initialize(nodep); |
bps = fat_bps_get(dev_handle); |
dps = bps / sizeof(fat_dentry_t); |
/* Read the block that contains the dentry of interest. */ |
b = _fat_block_get(dev_handle, idx->pfc, |
(idx->pdi * sizeof(fat_dentry_t)) / bps); |
assert(b); |
d = ((fat_dentry_t *)b->data) + (idx->pdi % dps); |
if (d->attr & FAT_ATTR_SUBDIR) { |
/* |
* The only directory which does not have this bit set is the |
* root directory itself. The root directory node is handled |
* and initialized elsewhere. |
*/ |
nodep->type = FAT_DIRECTORY; |
} else { |
nodep->type = FAT_FILE; |
} |
nodep->firstc = uint16_t_le2host(d->firstc); |
nodep->size = uint32_t_le2host(d->size); |
nodep->lnkcnt = 1; |
nodep->refcnt = 1; |
block_put(b); |
/* Link the idx structure with the node structure. */ |
nodep->idx = idx; |
idx->nodep = nodep; |
return nodep; |
} |
static void fat_node_put(void *node) |
{ |
fat_node_t *nodep = (fat_node_t *)node; |
if (!--nodep->refcnt) { |
list_append(&nodep->ffn_link, &ffn_head); |
} |
} |
static void *fat_create(int flags) |
{ |
return NULL; /* not supported at the moment */ |
} |
static int fat_destroy(void *node) |
{ |
return ENOTSUP; /* not supported at the moment */ |
} |
static bool fat_link(void *prnt, void *chld, const char *name) |
{ |
return false; /* not supported at the moment */ |
} |
static int fat_unlink(void *prnt, void *chld) |
{ |
return ENOTSUP; /* not supported at the moment */ |
} |
static void *fat_match(void *prnt, const char *component) |
{ |
fat_node_t *parentp = (fat_node_t *)prnt; |
char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1]; |
unsigned i, j; |
unsigned bps; /* bytes per sector */ |
unsigned dps; /* dentries per sector */ |
unsigned blocks; |
fat_dentry_t *d; |
block_t *b; |
bps = fat_bps_get(parentp->idx->dev_handle); |
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(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; |
else |
return 0; /* character mismatch */ |
case FAT_DENTRY_LAST: |
block_put(b); |
return NULL; |
default: |
case FAT_DENTRY_VALID: |
dentry_name_canonify(d, name); |
break; |
} |
if (strcmp(name, component) == 0) { |
/* hit */ |
fat_idx_t *idx = fat_idx_get_by_pos( |
parentp->idx->dev_handle, parentp->firstc, |
i * dps + j); |
if (!idx) { |
/* |
* Can happen if memory is low or if we |
* run out of 32-bit indices. |
*/ |
block_put(b); |
return NULL; |
} |
if (!dot_processed) { |
dot_processed = true; |
pos = -1; |
if (PLB_GET_CHAR(cur) != '.') |
void *node = fat_node_get(idx->dev_handle, |
idx->index); |
block_put(b); |
return node; |
} |
} |
block_put(b); |
} |
return NULL; |
} |
static fs_index_t fat_index_get(void *node) |
{ |
fat_node_t *fnodep = (fat_node_t *)node; |
if (!fnodep) |
return 0; |
continue; |
return fnodep->idx->index; |
} |
if (!ext_processed) { |
if ((pos == FAT_EXT_LEN - 1) || |
(dentry->ext[pos + 1] == FAT_PAD)) { |
/* this is the last character in ext */ |
ext_processed = true; |
static size_t fat_size_get(void *node) |
{ |
return ((fat_node_t *)node)->size; |
} |
if (dentry->ext[0] == FAT_PAD) { |
/* ext is empty; the match will fail */ |
ext_processed = true; |
} else if (PLB_GET_CHAR(cur) == dentry->ext[pos]) { |
static unsigned fat_lnkcnt_get(void *node) |
{ |
return ((fat_node_t *)node)->lnkcnt; |
} |
static bool fat_has_children(void *node) |
{ |
fat_node_t *nodep = (fat_node_t *)node; |
unsigned bps; |
unsigned dps; |
unsigned blocks; |
block_t *b; |
unsigned i, j; |
if (nodep->type != FAT_DIRECTORY) |
return false; |
bps = fat_bps_get(nodep->idx->dev_handle); |
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(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; |
} else { |
/* character mismatch */ |
return 0; |
case FAT_DENTRY_LAST: |
block_put(b); |
return false; |
default: |
case FAT_DENTRY_VALID: |
block_put(b); |
return true; |
} |
block_put(b); |
return true; |
} |
return 0; /* extra characters in the component */ |
block_put(b); |
} |
if (ext_processed || (name_processed && dentry->ext[0] == FAT_PAD)) |
return cur - start; |
else |
return 0; |
return false; |
} |
void fat_lookup(ipc_callid_t rid, ipc_call_t *request) |
static void *fat_root_get(dev_handle_t dev_handle) |
{ |
int first = IPC_GET_ARG1(*request); |
int second = IPC_GET_ARG2(*request); |
int dev_handle = IPC_GET_ARG3(*request); |
return NULL; /* TODO */ |
} |
static char fat_plb_get_char(unsigned pos) |
{ |
return fat_reg.plb_ro[pos % PLB_SIZE]; |
} |
static bool fat_is_directory(void *node) |
{ |
return ((fat_node_t *)node)->type == FAT_DIRECTORY; |
} |
static bool fat_is_file(void *node) |
{ |
return ((fat_node_t *)node)->type == FAT_FILE; |
} |
/** libfs operations */ |
libfs_ops_t fat_libfs_ops = { |
.match = fat_match, |
.node_get = fat_node_get, |
.node_put = fat_node_put, |
.create = fat_create, |
.destroy = fat_destroy, |
.link = fat_link, |
.unlink = fat_unlink, |
.index_get = fat_index_get, |
.size_get = fat_size_get, |
.lnkcnt_get = fat_lnkcnt_get, |
.has_children = fat_has_children, |
.root_get = fat_root_get, |
.plb_get_char = fat_plb_get_char, |
.is_directory = fat_is_directory, |
.is_file = fat_is_file |
}; |
void fat_lookup(ipc_callid_t rid, ipc_call_t *request) |
{ |
libfs_lookup(&fat_libfs_ops, fat_reg.fs_handle, rid, request); |
} |
/** |
* @} |
*/ |
/branches/tracing/uspace/srv/fs/fat/Makefile |
---|
44,7 → 44,8 |
OUTPUT = fat |
SOURCES = \ |
fat.c \ |
fat_ops.c |
fat_ops.c \ |
fat_idx.c |
OBJECTS := $(addsuffix .o,$(basename $(SOURCES))) |