Changeset a6e094f in mainline for uspace/srv/fs/minixfs/mfs_super.h

Timestamp:

2011-03-01T18:34:30Z (14 years ago)

Author:

Maurizio Lombardi <m.lombardi85@…>

Branches:

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

Children:

85d32df7

Parents:

128b8ee

Message:

Drop code copied from minix3

File:

• uspace/srv/fs/minixfs/mfs_super.h (modified) (1 diff)

uspace/srv/fs/minixfs/mfs_super.h

@@ -36 +36 @@
 #include "mfs_const.h"
 
-/* Super block table.  The root file system and every mounted file system
- * has an entry here.  The entry holds information about the sizes of the bit
- * maps and inodes.  The s_ninodes field gives the number of inodes available
- * for files and directories, including the root directory.  Inode 0 is 
- * on the disk, but not used.  Thus s_ninodes = 4 means that 5 bits will be
- * used in the bit map, bit 0, which is always 1 and not used, and bits 1-4
- * for files and directories.  The disk layout is:
- *
- *    Item        # blocks
- *    boot block      1
- *    super block     1    (offset 1kB)
- *    inode map     s_imap_blocks
- *    zone map      s_zmap_blocks
- *    inodes        (s_ninodes + 'inodes per block' - 1)/'inodes per block'
- *    unused        whatever is needed to fill out the current zone
- *    data zones    (s_zones - s_firstdatazone) << s_log_zone_size
- *
- */
 
-struct mfs_v3_superblock {
-        uint32_t        s_ninodes;              /*# usable inodes on the device*/
-        uint16_t        s_nzones;               /*total device size including bitmaps etc*/
-        int16_t         s_imap_blocks;          /*# of blocks used by inode bitmap*/
-        int16_t         s_zmap_blocks;          /*# of blocks used by zone bitmap*/
-        uint16_t        s_firstdatazone_old;    /*# of first data zone (small)*/
-        int16_t         s_log_zone_size;        /*log2 of blocks / zone*/
-        int16_t         s_pad;                  /*try to avoid compiler dependent padding*/
-        int32_t         s_max_size;             /*maximum file size*/
-        uint32_t        s_zones;                /*number of zones*/
-        int16_t         s_magic;                /*magic number to recognize superblocks*/
+struct mfs_superblock {
+        /*Total number of inodes on the device*/
+        uint32_t        s_ninodes;
+        /*Device size expressed as number of zones (unused)*/
+        uint16_t        s_nzones;
+        /*Number of inode bitmap blocks*/
+        int16_t         s_ibmap_blocks;
+        /*Number of zone bitmap blocks*/
+        int16_t         s_zbmap_blocks;
+        /*First data zone on device*/
+        uint16_t        s_first_data_zone;
+        /*Base 2 logarithm of the zone to block ratio*/
+        int16_t         s_log2_zone_size;
+        int16_t         s_pad;
+        /*Maximum file size expressed in bytes*/
+        int32_t         s_max_file_size;
+        /*Total number of zones on the device*/
+        uint32_t        s_total_zones;
+        /*Magic number used to recognize MinixFS and to detect on-disk endianness*/
+        int16_t         s_magic;
 
-        /* The following items are valid on disk only for V3 and above */
-        
+        /* The following fields are valid only for MinixFS V3 */
+
         int16_t         s_pad2;
-        uint16_t        s_block_size;           /*block size in bytes*/
-        int8_t          s_disk_version;         /*filesystem format sub-version*/
+        /*Filesystem block size expressed in bytes*/
+        uint16_t        s_block_size;
+        /*Filesystem disk format version*/
+        int8_t          s_disk_version;
 } __attribute__ ((packed));