* configure.ac: Changed version to 0.3.2.9.

[virt-top.git] / virt-df / virt_df_ext2.ml

diff --git a/virt-df/virt_df_ext2.ml b/virt-df/virt_df_ext2.ml
new file mode 100644 (file)
index 0000000..f58491a
--- /dev/null
+++ b/virt-df/virt_df_ext2.ml
@@ -0,0 +1,84 @@
+(* 'df' command for virtual domains.
+ * $Id$
+ *
+ * Support for EXT2/EXT3 filesystems.
+ *)
+
+open Unix
+open Printf
+
+(* Int64 operators for convenience. *)
+let (+^) = Int64.add
+let (-^) = Int64.sub
+let ( *^ ) = Int64.mul
+let (/^) = Int64.div
+
+let sector_size = Virt_df.sector_size
+let read_int32_le = Virt_df.read_int32_le
+
+let probe_ext2 target part_type fd start size =
+  LargeFile.lseek fd ((start+^2L) *^ sector_size) SEEK_SET;
+  let str = String.create 128 in
+  if read fd str 0 128 <> 128 then
+    failwith "error reading ext2/ext3 magic"
+  else (
+    if str.[56] != '\x53' || str.[57] != '\xEF' then (
+      Virt_df.ProbeFailed "partition marked EXT2/3 but no valid filesystem"
+    ) else (
+      (* Refer to <linux/ext2_fs.h> *)
+      let s_inodes_count = read_int32_le str 0 in
+      let s_blocks_count = read_int32_le str 4 in
+      let s_r_blocks_count = read_int32_le str 8 in
+      let s_free_blocks_count = read_int32_le str 12 in
+      let s_free_inodes_count = read_int32_le str 16 in
+      let s_first_data_block = read_int32_le str 20 in
+      let s_log_block_size = read_int32_le str 24 in
+      (*let s_log_frag_size = read_int32_le str 28 in*)
+      let s_blocks_per_group = read_int32_le str 32 in
+
+      (* Work out the block size in bytes. *)
+      let s_log_block_size = Int64.to_int s_log_block_size in
+      let block_size = 1024L in
+      let block_size = Int64.shift_left block_size s_log_block_size in
+
+      (* Number of groups. *)
+      let s_groups_count =
+       (s_blocks_count -^ s_first_data_block -^ 1L)
+       /^ s_blocks_per_group +^ 1L in
+
+(*
+      (* Number of group descriptors per block. *)
+      let s_inodes_per_block = s_blocksize / 
+       let s_desc_per_block = block_size / s_inodes_per_block in
+       let db_count =
+         (s_groups_count +^ s_desc_per_block -^ 1L)
+         /^ s_desc_per_block
+*)
+
+      (* Calculate the block overhead (used by superblocks, inodes, etc.)
+       * See fs/ext2/super.c.
+       *)
+      let overhead = s_first_data_block in
+      let overhead = (* XXX *) overhead in
+
+
+      Virt_df.Filesystem {
+       Virt_df.fs_name = "Linux ext2/3";
+       fs_block_size = block_size;
+       fs_blocks_total = s_blocks_count -^ overhead;
+       fs_blocks_reserved = s_r_blocks_count;
+       fs_blocks_avail = s_free_blocks_count;
+       fs_blocks_used = s_blocks_count -^ overhead -^ s_free_blocks_count;
+       fs_inodes_total = s_inodes_count;
+       fs_inodes_reserved = 0L;        (* XXX? *)
+       fs_inodes_avail = s_free_inodes_count;
+       fs_inodes_used = s_inodes_count (*-^ 0L*) -^ s_free_inodes_count;
+      }
+    )
+  )
+
+(* Register with main code. *)
+let () =
+  Virt_df.fs_register
+    [ 0x83 ]                           (* Partition type. *)
+    probe_ext2