From: Xiubo Li Date: Mon, 27 Mar 2017 09:07:41 +0000 (+0800) Subject: tcmu: Fix wrongly calculating of the base_command_size X-Git-Tag: v4.13~969^2~7 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=abe342a5b4b5aa579f6bf40ba73447c699e6b579;p=mirror_ubuntu-bionic-kernel.git tcmu: Fix wrongly calculating of the base_command_size The t_data_nents and t_bidi_data_nents are the numbers of the segments, but it couldn't be sure the block size equals to size of the segment. For the worst case, all the blocks are discontiguous and there will need the same number of iovecs, that's to say: blocks == iovs. So here just set the number of iovs to block count needed by tcmu cmd. Tested-by: Ilias Tsitsimpis Reviewed-by: Mike Christie Signed-off-by: Xiubo Li Cc: stable@vger.kernel.org # 3.18+ Signed-off-by: Nicholas Bellinger --- diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index e58dfd4fe448..9885d1b521fe 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -408,6 +408,13 @@ static inline size_t tcmu_cmd_get_data_length(struct tcmu_cmd *tcmu_cmd) return data_length; } +static inline uint32_t tcmu_cmd_get_block_cnt(struct tcmu_cmd *tcmu_cmd) +{ + size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd); + + return data_length / DATA_BLOCK_SIZE; +} + static sense_reason_t tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd) { @@ -435,8 +442,7 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd) * expensive to tell how many regions are freed in the bitmap */ base_command_size = max(offsetof(struct tcmu_cmd_entry, - req.iov[se_cmd->t_bidi_data_nents + - se_cmd->t_data_nents]), + req.iov[tcmu_cmd_get_block_cnt(tcmu_cmd)]), sizeof(struct tcmu_cmd_entry)); command_size = base_command_size + round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE);