Changeset 9a1d8ab in mainline for uspace/srv/fs/fat/fat.h

Timestamp:

2010-07-28T15:27:13Z (14 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

0b749a3, 482dde7, c0e1be7

Parents:

14f2100 (diff), dba4a23 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge from lp:~jakub/helenos/fs.

This merge adds two important optimizations for appending files and doing
sequential I/O on them.

File:

• uspace/srv/fs/fat/fat.h (modified) (2 diffs)

uspace/srv/fs/fat/fat.h

@@ -48 +48 @@
 
 #define min(a, b)               ((a) < (b) ? (a) : (b))
+
+/*
+ * Convenience macros for accessing some frequently used boot sector members.
+ */
+#define BPS(bs)         uint16_t_le2host((bs)->bps)
+#define SPC(bs)         (bs)->spc
+#define RSCNT(bs)       uint16_t_le2host((bs)->rscnt)
+#define FATCNT(bs)      (bs)->fatcnt
+#define SF(bs)          uint16_t_le2host((bs)->sec_per_fat)
+#define RDE(bs)         uint16_t_le2host((bs)->root_ent_max)
+#define TS(bs)          (uint16_t_le2host((bs)->totsec16) != 0 ? \
+                        uint16_t_le2host((bs)->totsec16) : \
+                        uint32_t_le2host(bs->totsec32))
 
 #define BS_BLOCK                0
@@ -198 +211 @@
         unsigned                refcnt;
         bool                    dirty;
+
+        /*
+         * Cache of the node's last and "current" cluster to avoid some
+         * unnecessary FAT walks.
+         */
+        /* Node's last cluster in FAT. */
+        bool            lastc_cached_valid;
+        fat_cluster_t   lastc_cached_value;
+        /* Node's "current" cluster, i.e. where the last I/O took place. */
+        bool            currc_cached_valid;
+        aoff64_t        currc_cached_bn;
+        fat_cluster_t   currc_cached_value;
 } fat_node_t;