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

 #define BS_BLOCK        0
 #define FIN_KEY_DEV_HANDLE  0
 #define FIN_KEY_INDEX       1
-/** Futex protecting both fin_hash and ffn_head. */
-futex_t fin_futex = FUTEX_INITIALIZER;
 /** Hash table of FAT in-core nodes. */
 hash_table_t fin_hash;
 /** List of free FAT in-core nodes. */
 link_t ffn_head;
 static void block_put(block_t *block)
+{
     /* TODO */
+}
+static fat_idx_t *fat_idx_map(fat_cluster_t pfc, unsigned pdi)
+{
+    return NULL;    /* 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
-/** Convert cluster number to an index within a FAT.
- *
- * Format Identifier and cluster numbering is considered.
- */
-#define C2FAT_IDX(c)    (1 + (c) - FAT_CLST_FIRST)
-static block_t *fat_block_get(dev_handle_t dev_handle, fs_index_t index,
+static block_t *fat_block_get(fat_node_t *nodep, off_t offset)
-    off_t offset)
+{
     block_t *bb;
     block_t *b;
     unsigned bps;
     unsigned spc;
     unsigned rde;
     unsigned rds;       /* root directory size */
     unsigned sf;
     unsigned ssa;       /* size of the system area */
     unsigned clusters;
-    unsigned clst = index;
+    fat_cluster_t clst = nodep->firstc;
     unsigned i;
-    bb = block_get(dev_handle, BS_BLOCK);
+    bb = block_get(nodep->idx->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);
     rds = (sizeof(fat_dentry_t) * rde) / bps;
     rds += ((sizeof(fat_dentry_t) * rde) % bps != 0);
     ssa = rscnt + fatcnt * sf + rds;
-    if (!index) {
+    if (nodep->idx->index == FAT_CLST_RES1) {
         /* root directory special case */
         assert(offset < rds);
+        b = block_get(nodep->idx->dev_handle,
-        b = block_get(dev_handle, rscnt + fatcnt * sf + offset);
+            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 = (C2FAT_IDX(clst) * sizeof(uint16_t)) / bps;
+        fsec = (clst * sizeof(fat_cluster_t)) / bps;
-        fidx = C2FAT_IDX(clst) % (bps / sizeof(uint16_t));
+        fidx = clst % (bps / sizeof(fat_cluster_t));
         /* read FAT1 */
-        b = block_get(dev_handle, rscnt + fsec);
+        b = block_get(nodep->idx->dev_handle, rscnt + fsec);
-        clst = uint16_t_le2host(((uint16_t *)b->data)[fidx]);
+        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 +
+    b = block_get(nodep->idx->dev_handle, ssa +
-        offset % spc);
+        (clst - FAT_CLST_FIRST) * spc + offset % spc);
     return b;
+}
 static void fat_node_initialize(fat_node_t *node)
+{
-    futex_initialize(&node->lock, 1);
+    node->idx = NULL;
     node->type = 0;
-    node->index = 0;
-    node->pindex = 0;
-    node->dev_handle = 0;
     link_initialize(&node->fin_link);
     link_initialize(&node->ffn_link);
     node->size = 0;
     node->lnkcnt = 0;
     node->refcnt = 0;
     unsigned dps;       /* dentries per sector */
     unsigned blocks;
     fat_dentry_t *d;
     block_t *b;
-    bps = fat_bps_get(parentp->dev_handle);
+    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->dev_handle, parentp->index, i);
+        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;
                 dentry_name_canonify(d, name);
                 break;
+            }
             if (strcmp(name, component) == 0) {
                 /* hit */
+                fat_idx_t *idx = fat_idx_map(parentp->firstc,
+                    i * dps + j);
-                void *node = fat_node_get(parentp->dev_handle,
+                void *node = fat_node_get(idx->dev_handle,
-                    (fs_index_t)uint16_t_le2host(d->firstc));
+                    idx->index);
                 block_put(b);
                 return node;
+            }
+        }
         block_put(b);
 static fs_index_t fat_index_get(void *node)
+{
     fat_node_t *fnodep = (fat_node_t *)node;
     if (!fnodep)
         return 0;
-    return fnodep->index;
+    return fnodep->idx->index;
+}
 static size_t fat_size_get(void *node)
+{
     return ((fat_node_t *)node)->size;
     unsigned i, j;
     if (nodep->type != FAT_DIRECTORY)
         return false;
-    bps = fat_bps_get(nodep->dev_handle);
+    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->dev_handle, nodep->index, i);
+        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;
     return false;
+}
 static void *fat_root_get(dev_handle_t dev_handle)
+{
-    return fat_node_get(dev_handle, 0);
+    return fat_node_get(dev_handle, FAT_CLST_RES1);
+}
 static char fat_plb_get_char(unsigned pos)
+{
     return fat_reg.plb_ro[pos % PLB_SIZE];

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/fs/fat/fat_ops.c @ 3478 – Rev 2863 → 2864