target: Fix range calculation in WRITE SAME emulation when num blocks == 0
When NUMBER OF LOGICAL BLOCKS is 0, WRITE SAME is supposed to write
all the blocks from the specified LBA through the end of the device.
However, dev->transport->get_blocks(dev) (perhaps confusingly) returns
the last valid LBA rather than the number of blocks, so the correct
number of blocks to write starting with lba is
dev->transport->get_blocks(dev) - lba + 1
(nab: Backport roland's for-3.6 patch to for-3.5)
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_cdb.c b/drivers/target/target_core_cdb.c
index 9888693..664f6e7 100644
--- a/drivers/target/target_core_cdb.c
+++ b/drivers/target/target_core_cdb.c
@@ -1095,7 +1095,7 @@
if (num_blocks != 0)
range = num_blocks;
else
- range = (dev->transport->get_blocks(dev) - lba);
+ range = (dev->transport->get_blocks(dev) - lba) + 1;
pr_debug("WRITE_SAME UNMAP: LBA: %llu Range: %llu\n",
(unsigned long long)lba, (unsigned long long)range);