)]}'
{
  "commit": "fa0ccd837e3dddb44c7db2f128a8bb7e4eabc21a",
  "tree": "ade071502f3e7cba423295890d828f0f301ad731",
  "parents": [
    "5d84070ee0a433620c57e85dac7f82faaec5fbb3"
  ],
  "author": {
    "name": "James Bottomley",
    "email": "James.Bottomley@HansenPartnership.com",
    "time": "Thu Jan 10 11:30:36 2008 -0600"
  },
  "committer": {
    "name": "Jens Axboe",
    "email": "jens.axboe@oracle.com",
    "time": "Mon Jan 28 10:54:11 2008 +0100"
  },
  "message": "block: implement drain buffers\n\nThese DMA drain buffer implementations in drivers are pretty horrible\nto do in terms of manipulating the scatterlist.  Plus they\u0027re being\ndone at least in drivers/ide and drivers/ata, so we now have code\nduplication.\n\nThe one use case for this, as I understand it is AHCI controllers doing\nPIO mode to mmc devices but translating this to DMA at the controller\nlevel.\n\nSo, what about adding a callback to the block layer that permits the\nadding of the drain buffer for the problem devices.  The idea is that\nyou\u0027d do this in slave_configure after you find one of these devices.\n\nThe beauty of doing it in the block layer is that it quietly adds the\ndrain buffer to the end of the sg list, so it automatically gets mapped\n(and unmapped) without anything unusual having to be done to the\nscatterlist in driver/scsi or drivers/ata and without any alteration to\nthe transfer length.\n\nSigned-off-by: James Bottomley \u003cJames.Bottomley@HansenPartnership.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n",
  "tree_diff": [
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      "old_path": "block/elevator.c",
      "new_id": "8cd5775acd7a2d4c1111acb0f823a57a46819dc0",
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      "new_path": "block/elevator.c"
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    },
    {
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      "old_path": "include/linux/blkdev.h",
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}