Search for md_page to be used as extent page started
from 0, which is completely valid md_page.
This page can be free when for example blob with id 0
was deleted and some other requested a new page for extent.
There are already existing blobs that have extents
pointing to 0, which means unallocated.
Unfortunetly it means 0 can never mean md page 0.
If that already occured for someone, this extent page was already
lost during blob/bs reload and nothing can be done.
With this in mind following assumptions are made for extent pages:
- 0 means unallocated extent page
- UINT32_MAX means we ran out of md pages, and should not be persisted
- [NEW] extent page can never occupy md page 0
That last one is new addition in this patch.
bs_allocate_cluster will now always try to find md page from 1 or higher.
Signed-off-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Change-Id: Ia17ce5bbca2fab4fb4487e4e263f3a0aa120bf17
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/4314
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>