Changeset fc35e98 in mainline for uspace/srv/fs/fat/fat_ops.c

Timestamp:

2011-04-07T19:14:33Z (14 years ago)

Author:

Oleg Romanenko <romanenko.oleg@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

97bc3ee

Parents:

ccca251

Message:

Basic support for FAT12 file system. With many limitations of course.

File:

• uspace/srv/fs/fat/fat_ops.c (modified) (3 diffs)

uspace/srv/fs/fat/fat_ops.c

@@ -104 +104 @@
         node->dirty = false;
         node->lastc_cached_valid = false;
-        node->lastc_cached_value = FAT_CLST_LAST1;
+        node->lastc_cached_value = FAT16_CLST_LAST1;
         node->currc_cached_valid = false;
         node->currc_cached_bn = 0;
-        node->currc_cached_value = FAT_CLST_LAST1;
+        node->currc_cached_value = FAT16_CLST_LAST1;
 }
 
@@ -945 +945 @@
  */
 
+
+#define RootDirSectors(bs)      (((RDE(bs)*32) + (BPS(bs)-1)) / BPS(bs))
+#define FATSz(bs)               SF(bs) != 0 ? SF(bs) : uint32_t_le2host((bs)->fat32.sectors_per_fat)
+#define DataSec(bs)             (TS(bs) - (RSCNT(bs) + (FATCNT(bs) * FATSz(bs)) + RootDirSectors(bs)))
+#define CountOfClusters(bs)     (DataSec(bs) / SPC(bs))
+
 void fat_mounted(ipc_callid_t rid, ipc_call_t *request)
 {
@@ -1000 +1006 @@
         }
 
+        /* Storing FAT type (12, 16, 32) in reserved field (bs->reserved) */
+        if (CountOfClusters(bs) < 4085) {
+        /* Volume is FAT12 */
+            printf("Found FAT12 filesystem\n");
+            (bs)->reserved = 12;
+        } else if (CountOfClusters(bs) < 65525) {
+        /* Volume is FAT16 */
+            printf("Found FAT16 filesystem\n");
+            (bs)->reserved = 16;
+        } else {
+        /* Volume is FAT32 */
+            printf("FAT32 is not supported by FAT driver. Sorry\n");
+            block_fini(devmap_handle);
+            async_answer_0(rid, ENOTSUP);
+            return;
+
+        }
+
         /* Do some simple sanity checks on the file system. */
         rc = fat_sanity_check(bs, devmap_handle);
         if (rc != EOK) {
+                printf("Sanity check failed\n");
                 (void) block_cache_fini(devmap_handle);
                 block_fini(devmap_handle);