Re: [PATCH] btrfs-progs: doc: update help/document of btrfs device remove

[Misono, Tomohiro]

On 2017/10/11 6:22, Satoru Takeuchi wrote:
> At Tue, 3 Oct 2017 17:12:39 +0900,
> Misono, Tomohiro wrote:
>>
>> This patch updates help/document of "btrfs device remove" in two points:
>>
>> 1. Add explanation of 'missing' for 'device remove'. This is only
>> written in wikipage currently.
>> (https://btrfs.wiki.kernel.org/index.php/Using_Btrfs_with_Multiple_Devices)
>>
>> 2. Add example of device removal in the man document. This is because
>> that explanation of "remove" says "See the example section below", but
>> there is no example of removal currently.
>>
>> Signed-off-by: Tomohiro Misono 
>> ---
>>  Documentation/btrfs-device.asciidoc | 19 +++
>>  cmds-device.c   | 10 +-
>>  2 files changed, 28 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/btrfs-device.asciidoc 
>> b/Documentation/btrfs-device.asciidoc
>> index 88822ec..dc523a9 100644
>> --- a/Documentation/btrfs-device.asciidoc
>> +++ b/Documentation/btrfs-device.asciidoc
>> @@ -75,6 +75,10 @@ The operation can take long as it needs to move all data 
>> from the device.
>>  It is possible to delete the device that was used to mount the filesystem. 
>> The
>>  device entry in mount table will be replaced by another device name with the
>>  lowest device id.
>> ++
>> +If device is mounted as degraded mode (-o degraded), special term "missing"
>> +can be used for . In that case, the first device that is described 
>> by
>> +the filesystem metadata, but not presented at the mount time will be 
>> removed.
>>  
>>  *delete* | [|...] ::
>>  Alias of remove kept for backward compatibility
>> @@ -206,6 +210,21 @@ data or the block groups occupy the whole first device.
>>  The device size of '/dev/sdb' as seen by the filesystem remains unchanged, 
>> but
>>  the logical space from 50-100GiB will be unused.
>>  
>> + REMOVE DEVICE 
> 
> It's a part of "TYPICAL USECASES" section. So it's also necessary to modify
> the following sentence
> 
> ===
> See the example section below.
> ===
> 
> to as follow.
> 
> ===
> See the *TYPICAL USECASES* section below.
> ===
> 
> Or just removing the above mentioned sentence is also OK since there is
> "See the section *TYPICAL USECASES* for some examples." in "DEVICE MANAGEMENT"
> section.
> 
>> +
>> +Device removal must satisfy the profile constraints, otherwise the command
>> +fails. For example:
>> +
>> + $ btrfs device remove /dev/sda /mnt
>> + $ ERROR: error removing device '/dev/sda': unable to go below two devices 
>> on raid1
> 
> s/^$  ERROR/ERROR/
> 
>> +
>> +
>> +In order to remove a device, you need to convert profile in this case:
>> +
>> + $ btrfs balance start -mconvert=dup /mnt
>> + $ btrfs balance start -dconvert=single /mnt
> 
> It's simpler to convert both the RAID configuration of data and metadata
> by the following one command.
> 
> $ btrfs balance -mconvert=dup -dconvert=single /mnt
> 
>> + $ btrfs device remove /dev/sda /mnt
>> +
>>  DEVICE STATS
>>  
>>  
>> diff --git a/cmds-device.c b/cmds-device.c
>> index 4337eb2..6cb53ff 100644
>> --- a/cmds-device.c
>> +++ b/cmds-device.c
>> @@ -224,9 +224,16 @@ static int _cmd_device_remove(int argc, char **argv,
>>  return !!ret;
>>  }
>>  
>> +#define COMMON_USAGE_REMOVE_DELETE \
>> +"", \
>> +"If 'missing' is specified for , the first device that is", \
>> +"described by the filesystem metadata, but not presented at the", \
>> +"mount time will be removed."
>> +
>>  static const char * const cmd_device_remove_usage[] = {
>>  "btrfs device remove | [|...] ",
>>  "Remove a device from a filesystem",
>> +COMMON_USAGE_REMOVE_DELETE,
>>  NULL
>>  };
>>  
>> @@ -237,7 +244,8 @@ static int cmd_device_remove(int argc, char **argv)
>>  
>>  static const char * const cmd_device_delete_usage[] = {
>>  "btrfs device delete | [|...] ",
>> -"Remove a device from a filesystem",
>> +"Remove a device from a filesystem (alias of \"btrfs device remove\")",
>> +COMMON_USAGE_REMOVE_DELETE,
>>  NULL
>>  };
> 
> This snippet is not related to the description of this patch.
> Dividing this patch is better.
> 
> Thanks,
> Satoru

Thanks for the review and I will follow the advice.
I think there should be 'missing-all' too to remove all the missing devices,
and will send the patches again.

Regards,
Tomohiro

> 
>>  
>> -- 
>> 2.9.5
>>
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Re: [PATCH] btrfs-progs: doc: update help/document of btrfs device remove

[Satoru Takeuchi]

At Tue, 3 Oct 2017 17:12:39 +0900,
Misono, Tomohiro wrote:
> 
> This patch updates help/document of "btrfs device remove" in two points:
> 
> 1. Add explanation of 'missing' for 'device remove'. This is only
> written in wikipage currently.
> (https://btrfs.wiki.kernel.org/index.php/Using_Btrfs_with_Multiple_Devices)
> 
> 2. Add example of device removal in the man document. This is because
> that explanation of "remove" says "See the example section below", but
> there is no example of removal currently.
> 
> Signed-off-by: Tomohiro Misono 
> ---
>  Documentation/btrfs-device.asciidoc | 19 +++
>  cmds-device.c   | 10 +-
>  2 files changed, 28 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/btrfs-device.asciidoc 
> b/Documentation/btrfs-device.asciidoc
> index 88822ec..dc523a9 100644
> --- a/Documentation/btrfs-device.asciidoc
> +++ b/Documentation/btrfs-device.asciidoc
> @@ -75,6 +75,10 @@ The operation can take long as it needs to move all data 
> from the device.
>  It is possible to delete the device that was used to mount the filesystem. 
> The
>  device entry in mount table will be replaced by another device name with the
>  lowest device id.
> ++
> +If device is mounted as degraded mode (-o degraded), special term "missing"
> +can be used for . In that case, the first device that is described by
> +the filesystem metadata, but not presented at the mount time will be removed.
>  
>  *delete* | [|...] ::
>  Alias of remove kept for backward compatibility
> @@ -206,6 +210,21 @@ data or the block groups occupy the whole first device.
>  The device size of '/dev/sdb' as seen by the filesystem remains unchanged, 
> but
>  the logical space from 50-100GiB will be unused.
>  
> + REMOVE DEVICE 

It's a part of "TYPICAL USECASES" section. So it's also necessary to modify
the following sentence

===
See the example section below.
===

to as follow.

===
See the *TYPICAL USECASES* section below.
===

Or just removing the above mentioned sentence is also OK since there is
"See the section *TYPICAL USECASES* for some examples." in "DEVICE MANAGEMENT"
section.

> +
> +Device removal must satisfy the profile constraints, otherwise the command
> +fails. For example:
> +
> + $ btrfs device remove /dev/sda /mnt
> + $ ERROR: error removing device '/dev/sda': unable to go below two devices 
> on raid1

s/^$  ERROR/ERROR/

> +
> +
> +In order to remove a device, you need to convert profile in this case:
> +
> + $ btrfs balance start -mconvert=dup /mnt
> + $ btrfs balance start -dconvert=single /mnt

It's simpler to convert both the RAID configuration of data and metadata
by the following one command.

$ btrfs balance -mconvert=dup -dconvert=single /mnt

> + $ btrfs device remove /dev/sda /mnt
> +
>  DEVICE STATS
>  
>  
> diff --git a/cmds-device.c b/cmds-device.c
> index 4337eb2..6cb53ff 100644
> --- a/cmds-device.c
> +++ b/cmds-device.c
> @@ -224,9 +224,16 @@ static int _cmd_device_remove(int argc, char **argv,
>   return !!ret;
>  }
>  
> +#define COMMON_USAGE_REMOVE_DELETE \
> + "", \
> + "If 'missing' is specified for , the first device that is", \
> + "described by the filesystem metadata, but not presented at the", \
> + "mount time will be removed."
> +
>  static const char * const cmd_device_remove_usage[] = {
>   "btrfs device remove | [|...] ",
>   "Remove a device from a filesystem",
> + COMMON_USAGE_REMOVE_DELETE,
>   NULL
>  };
>  
> @@ -237,7 +244,8 @@ static int cmd_device_remove(int argc, char **argv)
>  
>  static const char * const cmd_device_delete_usage[] = {
>   "btrfs device delete | [|...] ",
> - "Remove a device from a filesystem",
> + "Remove a device from a filesystem (alias of \"btrfs device remove\")",
> + COMMON_USAGE_REMOVE_DELETE,
>   NULL
>  };

This snippet is not related to the description of this patch.
Dividing this patch is better.

Thanks,
Satoru

>  
> -- 
> 2.9.5
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
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