block: Geometry and translation hints are now useless, purge them

There are two producers of these hints: drive_init() on behalf of
-drive, and hd_geometry_guess().

The only consumer of the hint is hd_geometry_guess().

The callers of hd_geometry_guess() call it only when drive_init()
didn't set the hints.  Therefore, drive_init()'s hints are never used.

Thus, hd_geometry_guess() only ever sees hints it produced itself in a
prior call.  Only the first call computes something, subsequent calls
just repeat the first call's results.  However, hd_geometry_guess() is
never called more than once: the device models don't, and the block
device is destroyed on unplug.  Thus, dropping the repeat feature
doesn't break anything now.

If a block device wasn't destroyed on unplug and could be reused with
a new device, then repeating old results would be wrong.  Thus,
dropping the repeat feature prevents future breakage.

This renders the hints unused.  Purge them from the block layer.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Markus Armbruster 2012-07-10 11:12:50 +02:00 committed by Kevin Wolf
parent 856dcba23a
commit 2b584959ed
9 changed files with 12 additions and 77 deletions

32
block.c
View file

@ -996,12 +996,6 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
bs_dest->block_timer = bs_src->block_timer;
bs_dest->io_limits_enabled = bs_src->io_limits_enabled;
/* geometry */
bs_dest->cyls = bs_src->cyls;
bs_dest->heads = bs_src->heads;
bs_dest->secs = bs_src->secs;
bs_dest->translation = bs_src->translation;
/* r/w error */
bs_dest->on_read_error = bs_src->on_read_error;
bs_dest->on_write_error = bs_src->on_write_error;
@ -2132,27 +2126,6 @@ void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
*nb_sectors_ptr = length;
}
void bdrv_set_geometry_hint(BlockDriverState *bs,
int cyls, int heads, int secs)
{
bs->cyls = cyls;
bs->heads = heads;
bs->secs = secs;
}
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
{
bs->translation = translation;
}
void bdrv_get_geometry_hint(BlockDriverState *bs,
int *pcyls, int *pheads, int *psecs)
{
*pcyls = bs->cyls;
*pheads = bs->heads;
*psecs = bs->secs;
}
/* throttling disk io limits */
void bdrv_set_io_limits(BlockDriverState *bs,
BlockIOLimit *io_limits)
@ -2161,11 +2134,6 @@ void bdrv_set_io_limits(BlockDriverState *bs,
bs->io_limits_enabled = bdrv_io_limits_enabled(bs);
}
int bdrv_get_translation_hint(BlockDriverState *bs)
{
return bs->translation;
}
void bdrv_set_on_error(BlockDriverState *bs, BlockErrorAction on_read_error,
BlockErrorAction on_write_error)
{