lkml.org 
[lkml]   [2009]   [Mar]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH try #1] Kconfig: cleanup block/Kconfig help descriptions
Nick,

I am trying to configure a linux-2.6.28.7 kernel.

Please explain why the switch for large block devices should be !64BIT.
I have a 64BIT system and currently cannot generate files greater than
2TB. Is this the problem? Should this be true for 64BIT systems?

Thanks,
don

Nick Andrew wrote:
> Modify the help descriptions of block/Kconfig for clarity, accuracy and consistency.
>
> Refactor the BLOCK description a bit. The wording "This permits ... to be
> removed" isn't quite right; the block layer is removed when the option
> is disabled, whereas most descriptions talk about what happens when the
> option is enabled. Reformat the list of what is affected by disabling the
> block layer.
>
> Add more examples of large block devices to LBD and strive for technical
> accuracy; block devices of size _exactly_ 2TB require CONFIG_LBD,
> not only "bigger than 2TB". Also try to say (perhaps not very clearly)
> that the config option is only needed when you want to have individual
> block devices of size >= 2TB, for example if you had 3 x 1TB disks in
> your computer you'd have a total storage size of 3TB but you wouldn't
> need the option unless you want to aggregate those disks into a RAID
> or LVM.
>
> Improve terminology and grammar on BLK_DEV_IO_TRACE.
>
> I also added the boilerplate "If unsure, say N" to most options.
>
> Precisely say "2TB and larger" for LSF.
>
> Indent the help text for BLK_DEV_BSG by 2 spaces in accordance with
> the standard.
>
> Signed-off-by: Nick Andrew <nick@nick-andrew.net>
> ---
> I'm not sure why LSF has "If unsure, say Y." I would have thought it
> pretty uncommon to have such large files. Also if you need LSF, you
> probably need LBD (can NFS handle 2TB+ files?). Is this a safety
> feature? How often is Grandma going to mount a filesystem containing
> 2TB+ sized files?
>
> Also the description for BLK_DEV_BSG is pretty obscure. Can anybody
> suggest why you'd want to do this or what tools you can use or even
> some documentation?
>
>
> block/Kconfig | 65 +++++++++++++++++++++++++++++++++++++--------------------
> 1 files changed, 42 insertions(+), 23 deletions(-)
>
>
> diff --git a/block/Kconfig b/block/Kconfig
> index 9bda7bc..a3d8509 100644
> --- a/block/Kconfig
> +++ b/block/Kconfig
> @@ -5,14 +5,18 @@ menuconfig BLOCK
> bool "Enable the block layer" if EMBEDDED
> default y
> help
> - This permits the block layer to be removed from the kernel if it's not
> - needed (on some embedded devices for example). If this option is
> - disabled, then blockdev files will become unusable and some
> - filesystems (such as ext3) will become unavailable.
> + Provide block layer support for the kernel.
>
> - This option will also disable SCSI character devices and USB storage
> - since they make use of various block layer definitions and
> - facilities.
> + Disable this option to remove the block layer support from the
> + kernel. This may be useful for embedded devices.
> +
> + If this option is disabled:
> +
> + - block device files will become unusable
> + - some filesystems (such as ext3) will become unavailable.
> +
> + Also, SCSI character devices and USB storage will be disabled since
> + they make use of various block layer definitions and facilities.
>
> Say Y here unless you know you really don't want to mount disks and
> suchlike.
> @@ -23,9 +27,20 @@ config LBD
> bool "Support for Large Block Devices"
> depends on !64BIT
> help
> - Say Y here if you want to attach large (bigger than 2TB) discs to
> - your machine, or if you want to have a raid or loopback device
> - bigger than 2TB. Otherwise say N.
> + Enable block devices of size 2TB and larger.
> +
> + This option is required to support the full capacity of large
> + (2TB+) block devices, including RAID, disk, Network Block Device,
> + Logical Volume Manager (LVM) and loopback.
> +
> + For example, RAID devices are frequently bigger than the capacity
> + of the largest individual hard drive.
> +
> + This option is not required if you have individual disk drives
> + which total 2TB+ and you are not aggregating the capacity into
> + a large block device (e.g. using RAID or LVM).
> +
> + If unsure, say N.
>
> config BLK_DEV_IO_TRACE
> bool "Support for tracing block io actions"
> @@ -33,19 +48,21 @@ config BLK_DEV_IO_TRACE
> select RELAY
> select DEBUG_FS
> help
> - Say Y here, if you want to be able to trace the block layer actions
> + Say Y here if you want to be able to trace the block layer actions
> on a given queue. Tracing allows you to see any traffic happening
> - on a block device queue. For more information (and the user space
> - support tools needed), fetch the blktrace app from:
> + on a block device queue. For more information (and the userspace
> + support tools needed), fetch the blktrace tools from:
>
> git://brick.kernel.dk/data/git/blktrace.git
>
> + If unsure, say N.
> +
> config LSF
> bool "Support for Large Single Files"
> depends on !64BIT
> help
> - Say Y here if you want to be able to handle very large files (bigger
> - than 2TB), otherwise say N.
> + Say Y here if you want to be able to handle very large files (2TB
> + and larger), otherwise say N.
>
> If unsure, say Y.
>
> @@ -53,14 +70,16 @@ config BLK_DEV_BSG
> bool "Block layer SG support v4 (EXPERIMENTAL)"
> depends on EXPERIMENTAL
> ---help---
> - Saying Y here will enable generic SG (SCSI generic) v4 support
> - for any block device.
> -
> - Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4
> - can handle complicated SCSI commands: tagged variable length cdbs
> - with bidirectional data transfers and generic request/response
> - protocols (e.g. Task Management Functions and SMP in Serial
> - Attached SCSI).
> + Saying Y here will enable generic SG (SCSI generic) v4 support
> + for any block device.
> +
> + Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4
> + can handle complicated SCSI commands: tagged variable length cdbs
> + with bidirectional data transfers and generic request/response
> + protocols (e.g. Task Management Functions and SMP in Serial
> + Attached SCSI).
> +
> + If unsure, say N.
>
> endif # BLOCK
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>

--
-----------------------------------------------------------------
| Don Fisher hdf3@comcast.net |
| 865 W. Cresta Loma Dr. VOICE: (520)888-7613 |
| Tucson, AZ. 85704-3705 |
-----------------------------------------------------------------


\
 
 \ /
  Last update: 2009-03-16 04:23    [from the cache]
©2003-2011 Jasper Spaans