Update status of superblock formats and fix misspellings in Documentation/md.txt
Signed-off-by: James Nelson <[email protected]>
diff -urN --exclude='*~' linux-2.6.9-original/Documentation/md.txt linux-2.6.9/Documentation/md.txt
--- linux-2.6.9-original/Documentation/md.txt 2004-10-18 17:54:38.000000000 -0400
+++ linux-2.6.9/Documentation/md.txt 2004-11-08 23:06:51.131605977 -0500
@@ -55,13 +55,13 @@
------------------
The md driver can support a variety of different superblock formats.
-(It doesn't yet, but it can)
+Currently, it supports superblock formats "0.90.0" and the "md-1" format
+introduced in the 2.5 development series.
-The kernel does *NOT* autodetect which format superblock is being
-used. It must be told.
+The kernel will autodetect which format superblock is being used.
Superblock format '0' is treated differently to others for legacy
-reasons.
+reasons - it is the original superblock format.
General Rules - apply for all superblock formats
@@ -69,6 +69,7 @@
An array is 'created' by writing appropriate superblocks to all
devices.
+
It is 'assembled' by associating each of these devices with an
particular md virtual device. Once it is completely assembled, it can
be accessed.
@@ -76,10 +77,10 @@
An array should be created by a user-space tool. This will write
superblocks to all devices. It will usually mark the array as
'unclean', or with some devices missing so that the kernel md driver
-can create approrpriate redundancy (copying in raid1, parity
+can create appropriate redundancy (copying in raid1, parity
calculation in raid4/5).
-When an array is assembled, it is first initialised with the
+When an array is assembled, it is first initialized with the
SET_ARRAY_INFO ioctl. This contains, in particular, a major and minor
version number. The major version number selects which superblock
format is to be used. The minor number might be used to tune handling
@@ -101,15 +102,16 @@
Specific Rules that apply to format-0 super block arrays, and
- arrays with no superblock (non-persistant).
+ arrays with no superblock (non-persistent).
-------------------------------------------------------------
An array can be 'created' by describing the array (level, chunksize
etc) in a SET_ARRAY_INFO ioctl. This must has major_version==0 and
raid_disks != 0.
-Then uninitialised devices can be added with ADD_NEW_DISK. The
+
+Then uninitialized devices can be added with ADD_NEW_DISK. The
structure passed to ADD_NEW_DISK must specify the state of the device
and it's role in the array.
-One started with RUN_ARRAY, uninitialised spares can be added with
+One started with RUN_ARRAY, uninitialized spares can be added with
HOT_ADD_DISK.
On Monday November 8, [email protected] wrote:
> Update status of superblock formats and fix misspellings in Documentation/md.txt
Thanks but ....
>
> -The kernel does *NOT* autodetect which format superblock is being
> -used. It must be told.
> +The kernel will autodetect which format superblock is being used.
This is an incorrect change. The kernel does *NOT* autodetect
superblock format. I'm you really think it does, please point me at
the code.
>
> -One started with RUN_ARRAY, uninitialised spares can be added with
> +One started with RUN_ARRAY, uninitialized spares can be added with
You corrected the wrong part of this line.
"One" at the beginning should be "Once".
"uninitialised" is correct - in the Locale of the author.
NeilBrown
Neil Brown wrote:
> On Monday November 8, [email protected] wrote:
>
>>Update status of superblock formats and fix misspellings in Documentation/md.txt
>
>
> Thanks but ....
>
>
>>
>>-The kernel does *NOT* autodetect which format superblock is being
>>-used. It must be told.
>>+The kernel will autodetect which format superblock is being used.
>
>
> This is an incorrect change. The kernel does *NOT* autodetect
> superblock format. I'm you really think it does, please point me at
> the code.
>
>
AFAICT, mddev_t->major_version is used to indicate the superblock format. That
form is used in add_new_disk(), but not in autostart_array().
It looks like the autostart_array function is set up to only work with the 0.90.0
superblock format, but the add_new_disk function calls the proper
superblock-handling form using super_types[] to switch between the type 0 and type
1 superblock formats.
OTOH, I could be wrong.
>>
>>-One started with RUN_ARRAY, uninitialised spares can be added with
>>+One started with RUN_ARRAY, uninitialized spares can be added with
>
>
> You corrected the wrong part of this line.
> "One" at the beginning should be "Once".
Oops. Missed that.
> "uninitialised" is correct - in the Locale of the author.
>
Do we go for Queen's English, American English, or what? Just so I can set up the
spell-checker in the proper locale.