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The default value remains 0 (no limit). Signed-off-by: Max Gurtovoy Signed-off-by: Aurelien Aptel Reviewed-by: Christoph Hellwig --- drivers/nvme/target/admin-cmd.c | 8 ++------ drivers/nvme/target/configfs.c | 27 +++++++++++++++++++++++++++ drivers/nvme/target/core.c | 8 ++++++++ drivers/nvme/target/nvmet.h | 13 +++++++++++++ drivers/nvme/target/zns.c | 6 +----- 5 files changed, 51 insertions(+), 11 deletions(-) diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c index ca5b08ce1211..4b759fc96cfd 100644 --- a/drivers/nvme/target/admin-cmd.c +++ b/drivers/nvme/target/admin-cmd.c @@ -687,12 +687,8 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req) id->cmic = NVME_CTRL_CMIC_MULTI_PORT | NVME_CTRL_CMIC_MULTI_CTRL | NVME_CTRL_CMIC_ANA; - /* Limit MDTS according to transport capability */ - if (ctrl->ops->get_mdts) - id->mdts = ctrl->ops->get_mdts(ctrl); - else - id->mdts = 0; - + /* Limit MDTS according to port config or transport capability */ + id->mdts = nvmet_ctrl_mdts(req); id->cntlid = cpu_to_le16(ctrl->cntlid); id->ver = cpu_to_le32(ctrl->subsys->ver); diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c index 3088e044dbcb..63d72fbf4d9d 100644 --- a/drivers/nvme/target/configfs.c +++ b/drivers/nvme/target/configfs.c @@ -302,6 +302,31 @@ static ssize_t nvmet_param_max_queue_size_store(struct config_item *item, CONFIGFS_ATTR(nvmet_, param_max_queue_size); +static ssize_t nvmet_param_mdts_show(struct config_item *item, char *page) +{ + struct nvmet_port *port = to_nvmet_port(item); + + return snprintf(page, PAGE_SIZE, "%d\n", port->mdts); +} + +static ssize_t nvmet_param_mdts_store(struct config_item *item, + const char *page, size_t count) +{ + struct nvmet_port *port = to_nvmet_port(item); + int ret; + + if (nvmet_is_port_enabled(port, __func__)) + return -EACCES; + ret = kstrtoint(page, 0, &port->mdts); + if (ret) { + pr_err("Invalid value '%s' for mdts\n", page); + return -EINVAL; + } + return count; +} + +CONFIGFS_ATTR(nvmet_, param_mdts); + #ifdef CONFIG_BLK_DEV_INTEGRITY static ssize_t nvmet_param_pi_enable_show(struct config_item *item, char *page) @@ -1996,6 +2021,7 @@ static struct configfs_attribute *nvmet_port_attrs[] = { &nvmet_attr_addr_tsas, &nvmet_attr_param_inline_data_size, &nvmet_attr_param_max_queue_size, + &nvmet_attr_param_mdts, #ifdef CONFIG_BLK_DEV_INTEGRITY &nvmet_attr_param_pi_enable, #endif @@ -2054,6 +2080,7 @@ static struct config_group *nvmet_ports_make(struct config_group *group, INIT_LIST_HEAD(&port->referrals); port->inline_data_size = -1; /* < 0 == let the transport choose */ port->max_queue_size = -1; /* < 0 == let the transport choose */ + port->mdts = -1; /* < 0 == let the transport choose */ port->disc_addr.trtype = NVMF_TRTYPE_MAX; port->disc_addr.portid = cpu_to_le16(portid); diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c index 9238e13bd480..779d8a130619 100644 --- a/drivers/nvme/target/core.c +++ b/drivers/nvme/target/core.c @@ -370,6 +370,14 @@ int nvmet_enable_port(struct nvmet_port *port) NVMET_MIN_QUEUE_SIZE, NVMET_MAX_QUEUE_SIZE); + /* + * If the transport didn't set the mdts properly, then clamp it to the + * target limits. Also set default values in case the transport didn't + * set it at all. + */ + if (port->mdts < 0 || port->mdts > NVMET_MAX_MDTS) + port->mdts = 0; + port->enabled = true; port->tr_ops = ops; return 0; diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h index 319d6a5e9cf0..1c94e2a01e34 100644 --- a/drivers/nvme/target/nvmet.h +++ b/drivers/nvme/target/nvmet.h @@ -214,6 +214,7 @@ struct nvmet_port { bool enabled; int inline_data_size; int max_queue_size; + int mdts; const struct nvmet_fabrics_ops *tr_ops; bool pi_enable; }; @@ -671,6 +672,7 @@ void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type, #define NVMET_MAX_QUEUE_SIZE 1024 #define NVMET_NR_QUEUES 128 #define NVMET_MAX_CMD(ctrl) (NVME_CAP_MQES(ctrl->cap) + 1) +#define NVMET_MAX_MDTS 255 /* * Nice round number that makes a list of nsids fit into a page. @@ -759,6 +761,17 @@ static inline bool nvmet_is_pci_ctrl(struct nvmet_ctrl *ctrl) return ctrl->port->disc_addr.trtype == NVMF_TRTYPE_PCI; } +/* Limit MDTS according to port config or transport capability */ +static inline u8 nvmet_ctrl_mdts(struct nvmet_req *req) +{ + struct nvmet_ctrl *ctrl = req->sq->ctrl; + u8 mdts = req->port->mdts; + + if (!ctrl->ops->get_mdts) + return mdts; + return min_not_zero(ctrl->ops->get_mdts(ctrl), mdts); +} + #ifdef CONFIG_NVME_TARGET_PASSTHRU void nvmet_passthru_subsys_free(struct nvmet_subsys *subsys); int nvmet_passthru_ctrl_enable(struct nvmet_subsys *subsys); diff --git a/drivers/nvme/target/zns.c b/drivers/nvme/target/zns.c index aeaf73b54c3a..f00921931eb6 100644 --- a/drivers/nvme/target/zns.c +++ b/drivers/nvme/target/zns.c @@ -69,7 +69,6 @@ bool nvmet_bdev_zns_enable(struct nvmet_ns *ns) void nvmet_execute_identify_ctrl_zns(struct nvmet_req *req) { u8 zasl = req->sq->ctrl->subsys->zasl; - struct nvmet_ctrl *ctrl = req->sq->ctrl; struct nvme_id_ctrl_zns *id; u16 status; @@ -79,10 +78,7 @@ void nvmet_execute_identify_ctrl_zns(struct nvmet_req *req) goto out; } - if (ctrl->ops->get_mdts) - id->zasl = min_t(u8, ctrl->ops->get_mdts(ctrl), zasl); - else - id->zasl = zasl; + id->zasl = min_not_zero(nvmet_ctrl_mdts(req), zasl); status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id)); -- 2.51.0