[Nbd] [PATCH v2 7/9] brd: use generic helper to set max_discard_sectors
- To: dwmw2@...1270..., axboe@...161..., shli@...1285..., Paul.Clements@...124..., npiggin@...161..., neilb@...122..., cjb@...1330..., adrian.hunter@...1303..., James.Bottomley@...1336..., JBottomley@...1298...
- Cc: nbd-general@lists.sourceforge.net, Namjae Jeon <linkinjeon@...17...>, Vivek Trivedi <t.vivek@...1329...>, linux-scsi@...25..., Namjae Jeon <namjae.jeon@...1329...>, linux-mmc@...25..., linux-kernel@...25..., linux-raid@...25..., jcmvbkbc@...17..., linux-mtd@...1331...
- Subject: [Nbd] [PATCH v2 7/9] brd: use generic helper to set max_discard_sectors
- From: Namjae Jeon <linkinjeon@...17...>
- Date: Sat, 20 Apr 2013 01:42:06 +0900
- Message-id: <1366389726-19553-1-git-send-email-linkinjeon@...17...>
From: Namjae Jeon <namjae.jeon@...1329...>
It is better to use blk_queue_max_discard_sectors helper
function to set max_discard_sectors as it checks
max_discard_sectors upper limit UINT_MAX >> 9
similar issue was reported for mmc in below link
https://lkml.org/lkml/2013/4/1/292
If multiple discard requests get merged, merged discard request's
size exceeds 4GB, there is possibility that merged discard request's
__data_len field may overflow.
This patch fixes this issue.
Signed-off-by: Namjae Jeon <namjae.jeon@...1329...>
Signed-off-by: Vivek Trivedi <t.vivek@...1329...>
---
drivers/block/brd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index f1a29f8..108646d 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -479,7 +479,7 @@ static struct brd_device *brd_alloc(int i)
blk_queue_bounce_limit(brd->brd_queue, BLK_BOUNCE_ANY);
brd->brd_queue->limits.discard_granularity = PAGE_SIZE;
- brd->brd_queue->limits.max_discard_sectors = UINT_MAX;
+ blk_queue_max_discard_sectors(brd->brd_queue, UINT_MAX >> 9);
brd->brd_queue->limits.discard_zeroes_data = 1;
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, brd->brd_queue);
--
1.7.9.5
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