diff options
| author | Mike Christie <mchristi@redhat.com> | 2016-06-02 20:12:37 -0500 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2016-07-20 00:58:36 -0700 |
| commit | ea263c7fada4af8ec7fe5fcfd6e7d7705a89351b (patch) | |
| tree | 72beb3f878ba29726a189211cc4e6dacd9a6f339 /drivers/target/target_core_device.c | |
| parent | 064cdd2d91c2805d788876082f31cc63506f22c3 (diff) | |
target: Fix max_unmap_lba_count calc overflow
max_discard_sectors only 32bits, and some non scsi backend
devices will set this to the max 0xffffffff, so we can end up
overflowing during the max_unmap_lba_count calculation.
This fixes a regression caused by my patch:
commit 8a9ebe717a133ba7bc90b06047f43cc6b8bcb8b3
Author: Mike Christie <mchristi@redhat.com>
Date: Mon Jan 18 14:09:27 2016 -0600
target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors
which can result in extra discards being sent to due the overflow
causing max_unmap_lba_count to be smaller than what the backing
device can actually support.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target/target_core_device.c')
| -rw-r--r-- | drivers/target/target_core_device.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index a4046ca6e60d..6b423485c5d6 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -821,13 +821,15 @@ struct se_device *target_alloc_device(struct se_hba *hba, const char *name) * in ATA and we need to set TPE=1 */ bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib, - struct request_queue *q, int block_size) + struct request_queue *q) { + int block_size = queue_logical_block_size(q); + if (!blk_queue_discard(q)) return false; - attrib->max_unmap_lba_count = (q->limits.max_discard_sectors << 9) / - block_size; + attrib->max_unmap_lba_count = + q->limits.max_discard_sectors >> (ilog2(block_size) - 9); /* * Currently hardcoded to 1 in Linux/SCSI code.. */ |