[PATCH] nvmet: allow setting ctrl to ready without iosqes/iocqes set

[ran.anner at dell.com]

From: Ran Anner <Ran.Anner at dell.com>

According to the spec we should fail creation of IO queues
if iosqes or iocqes properties are not set but does not mention
preventing from changing ctrl status to ready.
We have seen host implementation which sets the property to 0x1
and waits endlessly until ctrl status changes to ready.

Signed-off-by: Ran Anner <Ran.Anner at dell.com>
---
 drivers/nvme/target/core.c        | 39 +------------------------------
 drivers/nvme/target/fabrics-cmd.c |  9 +++++++
 drivers/nvme/target/nvmet.h       | 34 +++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 38 deletions(-)

diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index adbede9ab7f3..559dc7354adb 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -1078,48 +1078,11 @@ void nvmet_req_free_sgls(struct nvmet_req *req)
 }
 EXPORT_SYMBOL_GPL(nvmet_req_free_sgls);
 
-static inline bool nvmet_cc_en(u32 cc)
-{
-	return (cc >> NVME_CC_EN_SHIFT) & 0x1;
-}
-
-static inline u8 nvmet_cc_css(u32 cc)
-{
-	return (cc >> NVME_CC_CSS_SHIFT) & 0x7;
-}
-
-static inline u8 nvmet_cc_mps(u32 cc)
-{
-	return (cc >> NVME_CC_MPS_SHIFT) & 0xf;
-}
-
-static inline u8 nvmet_cc_ams(u32 cc)
-{
-	return (cc >> NVME_CC_AMS_SHIFT) & 0x7;
-}
-
-static inline u8 nvmet_cc_shn(u32 cc)
-{
-	return (cc >> NVME_CC_SHN_SHIFT) & 0x3;
-}
-
-static inline u8 nvmet_cc_iosqes(u32 cc)
-{
-	return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf;
-}
-
-static inline u8 nvmet_cc_iocqes(u32 cc)
-{
-	return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf;
-}
-
 static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl)
 {
 	lockdep_assert_held(&ctrl->lock);
 
-	if (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
-	    nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES ||
-	    nvmet_cc_mps(ctrl->cc) != 0 ||
+	if (nvmet_cc_mps(ctrl->cc) != 0 ||
 	    nvmet_cc_ams(ctrl->cc) != 0 ||
 	    nvmet_cc_css(ctrl->cc) != 0) {
 		ctrl->csts = NVME_CSTS_CFS;
diff --git a/drivers/nvme/target/fabrics-cmd.c b/drivers/nvme/target/fabrics-cmd.c
index 1420a8e3e0b1..421ab564ed5c 100644
--- a/drivers/nvme/target/fabrics-cmd.c
+++ b/drivers/nvme/target/fabrics-cmd.c
@@ -259,6 +259,15 @@ static void nvmet_execute_io_connect(struct nvmet_req *req)
 		goto out_ctrl_put;
 	}
 
+	if (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES ||
+			nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES) {
+		pr_warn("reject connect cmd (IOSQES %u IOCSES %u)",
+				nvmet_cc_iosqes(ctrl->cc),
+				nvmet_cc_iocqes(ctrl->cc));
+		status = NVME_SC_QUEUE_SIZE;
+		goto out_ctrl_put;
+	}
+
 	status = nvmet_install_queue(ctrl, req);
 	if (status) {
 		/* pass back cntlid that had the issue of installing queue */
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 5566ed403576..18213edb8a07 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -616,4 +616,38 @@ static inline sector_t nvmet_lba_to_sect(struct nvmet_ns *ns, __le64 lba)
 	return le64_to_cpu(lba) << (ns->blksize_shift - SECTOR_SHIFT);
 }
 
+static inline bool nvmet_cc_en(u32 cc)
+{
+	return (cc >> NVME_CC_EN_SHIFT) & 0x1;
+}
+
+static inline u8 nvmet_cc_css(u32 cc)
+{
+	return (cc >> NVME_CC_CSS_SHIFT) & 0x7;
+}
+
+static inline u8 nvmet_cc_mps(u32 cc)
+{
+	return (cc >> NVME_CC_MPS_SHIFT) & 0xf;
+}
+
+static inline u8 nvmet_cc_ams(u32 cc)
+{
+	return (cc >> NVME_CC_AMS_SHIFT) & 0x7;
+}
+
+static inline u8 nvmet_cc_shn(u32 cc)
+{
+	return (cc >> NVME_CC_SHN_SHIFT) & 0x3;
+}
+
+static inline u8 nvmet_cc_iosqes(u32 cc)
+{
+	return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf;
+}
+
+static inline u8 nvmet_cc_iocqes(u32 cc)
+{
+	return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf;
+}
 #endif /* _NVMET_H */
-- 
2.18.2