From 3d3f9d56a57014174ea9b997c95b71b50fdc4cc3 Mon Sep 17 00:00:00 2001 From: Bodo Stroesser Date: Sun, 26 Jul 2020 17:35:07 +0200 Subject: scsi: target: tcmu: Factor out new helper ring_insert_padding The new helper ring_insert_padding is split off from and then called by queue_cmd_ring. It inserts a padding if necessary. The new helper will in a subsequent patch be used during writing of TMR notifications to command ring. Link: https://lore.kernel.org/r/20200726153510.13077-6-bstroesser@ts.fujitsu.com Reviewed-by: Mike Christie Signed-off-by: Bodo Stroesser Signed-off-by: Martin K. Petersen --- drivers/target/target_core_user.c | 51 +++++++++++++++++++++++---------------- 1 file changed, 30 insertions(+), 21 deletions(-) (limited to 'drivers/target/target_core_user.c') diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 25c480fde9ee..eb68c5fee7b7 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -926,6 +926,34 @@ static int add_to_qfull_queue(struct tcmu_cmd *tcmu_cmd) return 0; } +static uint32_t ring_insert_padding(struct tcmu_dev *udev, size_t cmd_size) +{ + struct tcmu_cmd_entry_hdr *hdr; + struct tcmu_mailbox *mb = udev->mb_addr; + uint32_t cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ + + /* Insert a PAD if end-of-ring space is too small */ + if (head_to_end(cmd_head, udev->cmdr_size) < cmd_size) { + size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); + + hdr = (void *) mb + CMDR_OFF + cmd_head; + tcmu_hdr_set_op(&hdr->len_op, TCMU_OP_PAD); + tcmu_hdr_set_len(&hdr->len_op, pad_size); + hdr->cmd_id = 0; /* not used for PAD */ + hdr->kflags = 0; + hdr->uflags = 0; + tcmu_flush_dcache_range(hdr, sizeof(*hdr)); + + UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); + tcmu_flush_dcache_range(mb, sizeof(*mb)); + + cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ + WARN_ON(cmd_head != 0); + } + + return cmd_head; +} + /** * queue_cmd_ring - queue cmd to ring or internally * @tcmu_cmd: cmd to queue @@ -941,7 +969,7 @@ static int queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, sense_reason_t *scsi_err) struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; struct se_cmd *se_cmd = tcmu_cmd->se_cmd; size_t base_command_size, command_size; - struct tcmu_mailbox *mb; + struct tcmu_mailbox *mb = udev->mb_addr; struct tcmu_cmd_entry *entry; struct iovec *iov; int iov_cnt, cmd_id; @@ -980,8 +1008,6 @@ static int queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, sense_reason_t *scsi_err) if (!list_empty(&udev->qfull_queue)) goto queue; - mb = udev->mb_addr; - cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ if ((command_size > (udev->cmdr_size / 2)) || data_length > udev->data_size) { pr_warn("TCMU: Request of size %zu/%zu is too big for %u/%zu " @@ -1001,24 +1027,7 @@ static int queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, sense_reason_t *scsi_err) goto queue; } - /* Insert a PAD if end-of-ring space is too small */ - if (head_to_end(cmd_head, udev->cmdr_size) < command_size) { - size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); - - entry = (void *) mb + CMDR_OFF + cmd_head; - tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_PAD); - tcmu_hdr_set_len(&entry->hdr.len_op, pad_size); - entry->hdr.cmd_id = 0; /* not used for PAD */ - entry->hdr.kflags = 0; - entry->hdr.uflags = 0; - tcmu_flush_dcache_range(entry, sizeof(entry->hdr)); - - UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); - tcmu_flush_dcache_range(mb, sizeof(*mb)); - - cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ - WARN_ON(cmd_head != 0); - } + cmd_head = ring_insert_padding(udev, command_size); entry = (void *) mb + CMDR_OFF + cmd_head; memset(entry, 0, command_size); -- cgit