diff options
author | Roger Pau Monne <roger.pau@citrix.com> | 2013-08-12 12:53:43 +0200 |
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committer | Jens Axboe <axboe@kernel.dk> | 2013-11-08 09:10:27 -0700 |
commit | c47206e25f28232ff979994c32758c82841d81cd (patch) | |
tree | 5b3a5b0830778f0bffaa97eee715f7a99ac3f01b /drivers/block/xen-blkback | |
parent | fbe363c476afe8ec992d3baf682670a4bd1b6ce6 (diff) |
xen-blkfront: improve aproximation of required grants per request
Improve the calculation of required grants to process a request by
using nr_phys_segments instead of always assuming a request is going
to use all posible segments.
nr_phys_segments contains the number of scatter-gather DMA addr+len
pairs, which is basically what we put at every granted page.
for_each_sg iterates over the DMA addr+len pairs and uses a grant
page for each of them.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block/xen-blkback')
0 files changed, 0 insertions, 0 deletions