[PATCH v2 2/6] parallels.txt: fix bitmap L1 table description

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

Actually L1 table entry offset is in 512 bytes sectors. Fix the spec.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 docs/interop/parallels.txt | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/docs/interop/parallels.txt b/docs/interop/parallels.txt
index f15bf35bd1..73af9a2c4b 100644
--- a/docs/interop/parallels.txt
+++ b/docs/interop/parallels.txt
@@ -208,21 +208,24 @@ of its data area are:
   28 - 31:    l1_size
               The number of entries in the L1 table of the bitmap.
 
-  variable:   l1_table (8 * l1_size bytes)
-              L1 offset table (in bytes)
+  variable:   L1 offset table (l1_table), size: 8 * l1_size bytes
 
-A dirty bitmap is stored using a one-level structure for the mapping to host
-clusters - an L1 table.
+Dirty bitmap is stored in the array of clusters inside Parallels Image file.
+Offsets of these clusters are saved in L1 offset table here. Each L1 table
+entry is a 64bit integer described below:
 
-Given an offset in bytes into the bitmap data, the offset in bytes into the
-image file can be obtained as follows:
+Given an offset in bytes into the bitmap data, corresponding L1 entry is
 
-    offset = l1_table[offset / cluster_size] + (offset % cluster_size)
+    l1_table[offset / cluster_size]
 
-If an L1 table entry is 0, the corresponding cluster of the bitmap is assumed
-to be zero.
+If L1 table entry is 0, all bits in the corresponding cluster of the bitmap
+are assumed to be 0.
 
-If an L1 table entry is 1, the corresponding cluster of the bitmap is assumed
-to have all bits set.
+If L1 table entry is 1, all bits in the corresponding cluster of the bitmap
+are assumed to be 1.
 
-If an L1 table entry is not 0 or 1, it allocates a cluster from the data area.
+If an L1 table entry is not 0 or 1, it contains corresponding cluster offset
+(in 512b sectors). Given an offset in bytes into the bitmap data the offset in
+bytes into the image file can be obtained as follows:
+
+    offset = l1_table[offset / cluster_size] * 512 + (offset % cluster_size)
-- 
2.29.2