eMMC4.5 Context ID

Registered by Saugata Das on 2012-02-10

Support MMC-4.5 context ID feature in Linux MMC stack and improve file system (EXT4) to utilize this feature. Following approaches need to be explored,

From delayed allocation,
1. Contiguous blocks from the newly created large files are grouped into a large unit context
2. Contiguous blocks from small files which are newly created are put into a large unit context
(Explore the usage of mballoc on both the above points)

In case, blocks are not contiguous then close the context and reopen.

For blocks which are overwritten, use context 0

Discussions in lkml after the first version of patchset was posted by Saugata Das:-
http://thread.gmane.org/gmane.linux.kernel.mmc/14864

Blueprint information

Status:
Started
Approver:
Venkatraman S
Priority:
Undefined
Drafter:
Saugata Das
Direction:
Needs approval
Assignee:
None
Definition:
Approved
Series goal:
None
Implementation:
Blocked
Milestone target:
None
Started by
Saugata Das on 2012-05-03

Related branches

Sprints

Whiteboard

Meta:
Headline : Implement context ID in the Linux MMC layer
Acceptance:
RoadmapId: KWG2011-EMMC-4.5-SUPPORT

[svenkatr 2012-10-17] no assignee now that sdas left. So far there were 2 different designs / patchsets posted for this but both were not accepted in lkml. The version posted by sdas has to be abandoned and it needs to be redesigned, based on the feedback in lkml

[jakub-pavelek 2012-10-17] Putting this on backburner - priority stays Undefined, no work expected.

(?)

Work Items

Work items for 12.01:
[saugata.das] Study context ID feature of MMC-4.5 : DONE
[saugata.das] Update mmci driver to handle SBC : DONE

Work items for 12.05:
[saugata.das] Implement context ID feature : DONE
[saugata.das] Study EXT4 file system for context usage identification : DONE
[saugata.das] Internal review : DONE
[saugata.das] RFC Publish to community (http://thread.gmane.org/gmane.linux.kernel.mmc/14864) : DONE

Work items for 12.07:
[saugata.das] Explore mballoc : TODO

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