diff options
author | Christoph Hellwig <hch@infradead.org> | 2009-09-30 13:52:12 +0200 |
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committer | Jens Axboe <jens.axboe@oracle.com> | 2009-10-01 21:15:46 +0200 |
commit | 1122a26f2abe4245ccdaed95ec23f63fe086b332 (patch) | |
tree | ad06f119f283cf8a6313681055e8132ba2851ddb /lib/Kconfig | |
parent | 3bd0f0c763e497c8674b28e3df2732f48683dabd (diff) |
block: use normal I/O path for discard requests
prepare_discard_fn() was being called in a place where memory allocation
was effectively impossible. This makes it inappropriate for all but
the most trivial translations of Linux's DISCARD operation to the block
command set. Additionally adding a payload there makes the ownership
of the bio backing unclear as it's now allocated by the device driver
and not the submitter as usual.
It is replaced with QUEUE_FLAG_DISCARD which is used to indicate whether
the queue supports discard operations or not. blkdev_issue_discard now
allocates a one-page, sector-length payload which is the right thing
for the common ATA and SCSI implementations.
The mtd implementation of prepare_discard_fn() is replaced with simply
checking for the request being a discard.
Largely based on a previous patch from Matthew Wilcox <matthew@wil.cx>
which did the prepare_discard_fn but not the different payload allocation
yet.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'lib/Kconfig')
0 files changed, 0 insertions, 0 deletions