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| author | Philipp Reisner <philipp.reisner@linbit.com> | 2013-06-25 16:50:08 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2013-06-28 16:04:36 +0200 |
| commit | d752b2696072ed52fd5afab08b601e2220a3b87e (patch) | |
| tree | a6a88c4af1c6e82575d58a68651f0156431d5c09 /include/linux/drbd_limits.h | |
| parent | e96c96333fe5a4f252cc4e1d7edde8ee7dce7dfe (diff) | |
| download | lwn-d752b2696072ed52fd5afab08b601e2220a3b87e.tar.gz lwn-d752b2696072ed52fd5afab08b601e2220a3b87e.zip | |
drbd: Allow online change of al-stripes and al-stripe-size
Allow to change the AL layout with an resize operation. For that
the reisze command gets two new fields: al_stripes and al_stripe_size.
In order to make the operation crash save:
1) Lock out all IO and MD-IO
2) Write the super block with MDF_PRIMARY_IND clear
3) write the bitmap to the new location (all zeros, since
we allow only while connected)
4) Initialize the new AL-area
5) Write the super block with the restored MDF_PRIMARY_IND.
6) Unfreeze all IO
Since the AL-layout has no influence on the protocol, this operation
needs to be beforemed on both sides of a resource (if intended).
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux/drbd_limits.h')
| -rw-r--r-- | include/linux/drbd_limits.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h index 1fedf2b17cc8..17e50bb00521 100644 --- a/include/linux/drbd_limits.h +++ b/include/linux/drbd_limits.h @@ -215,4 +215,13 @@ #define DRBD_ALWAYS_ASBP_DEF 0 #define DRBD_USE_RLE_DEF 1 +#define DRBD_AL_STRIPES_MIN 1 +#define DRBD_AL_STRIPES_MAX 1024 +#define DRBD_AL_STRIPES_DEF 1 +#define DRBD_AL_STRIPES_SCALE '1' + +#define DRBD_AL_STRIPE_SIZE_MIN 4 +#define DRBD_AL_STRIPE_SIZE_MAX 16777216 +#define DRBD_AL_STRIPE_SIZE_DEF 32 +#define DRBD_AL_STRIPE_SIZE_SCALE 'k' /* kilobytes */ #endif |