From: Sagi Grimberg sagi@grimberg.me
[ Upstream commit cb8563f5c735a042ea2dd7df1ad55ae06d63ffeb ]
When the host sends multiple h2cdata PDUs, we keep track on the receive progress and calculate the scatterlist index and offsets.
The issue is that sg_offset should only be kept for the first iov entry we map in the iovec as this is the difference between our cursor and the sg entry offset itself.
In addition, the sg index was calculated wrong because we should not round up when dividing the command byte offset with PAG_SIZE.
Fixes: 872d26a391da ("nvmet-tcp: add NVMe over TCP target driver") Reported-by: Narayan Ayalasomayajula Narayan.Ayalasomayajula@wdc.com Tested-by: Narayan Ayalasomayajula Narayan.Ayalasomayajula@wdc.com Signed-off-by: Sagi Grimberg sagi@grimberg.me Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/target/tcp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index dc1f0f6471896..aacf06f0b4312 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -305,7 +305,7 @@ static void nvmet_tcp_map_pdu_iovec(struct nvmet_tcp_cmd *cmd) length = cmd->pdu_len; cmd->nr_mapped = DIV_ROUND_UP(length, PAGE_SIZE); offset = cmd->rbytes_done; - cmd->sg_idx = DIV_ROUND_UP(offset, PAGE_SIZE); + cmd->sg_idx = offset / PAGE_SIZE; sg_offset = offset % PAGE_SIZE; sg = &cmd->req.sg[cmd->sg_idx];
@@ -318,6 +318,7 @@ static void nvmet_tcp_map_pdu_iovec(struct nvmet_tcp_cmd *cmd) length -= iov_len; sg = sg_next(sg); iov++; + sg_offset = 0; }
iov_iter_kvec(&cmd->recv_msg.msg_iter, READ, cmd->iov,