dm: factor out max_io_len_target_boundary

Split max_io_len_target_boundary out of max_io_len so that the discard
support can make use of it without duplicating max_io_len code.

Avoiding max_io_len's split_io logic enables DM's discard support to
submit the entire discard request to a target.  But discards must still
be split on target boundaries.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Mike Snitzer
2010-08-12 04:14:10 +01:00
committed by Alasdair G Kergon
parent 06a426cee9
commit 56a67df766
2 changed files with 24 additions and 8 deletions

View File

@@ -398,6 +398,12 @@ void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
#define dm_array_too_big(fixed, obj, num) \
((num) > (UINT_MAX - (fixed)) / (obj))
/*
* Sector offset taken relative to the start of the target instead of
* relative to the start of the device.
*/
#define dm_target_offset(ti, sector) ((sector) - (ti)->begin)
static inline sector_t to_sector(unsigned long n)
{
return (n >> SECTOR_SHIFT);