nvmet: add ns write protect support
This patch implements the Namespace Write Protect feature described in
"NVMe TP 4005a Namespace Write Protect". In this version, we implement
No Write Protect and Write Protect states for target ns which can be
toggled by set-features commands from the host side.
For write-protect state transition, we need to flush the ns specified
as a part of command so we also add helpers for carrying out synchronous
flush operations.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: fixed an incorrect endianess conversion, minor cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 2294104..ec9af4e 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -58,6 +58,7 @@ struct nvmet_ns {
struct percpu_ref ref;
struct block_device *bdev;
struct file *file;
+ bool readonly;
u32 nsid;
u32 blksize_shift;
loff_t size;
@@ -429,6 +430,9 @@ int nvmet_bdev_ns_enable(struct nvmet_ns *ns);
int nvmet_file_ns_enable(struct nvmet_ns *ns);
void nvmet_bdev_ns_disable(struct nvmet_ns *ns);
void nvmet_file_ns_disable(struct nvmet_ns *ns);
+u16 nvmet_bdev_flush(struct nvmet_req *req);
+u16 nvmet_file_flush(struct nvmet_req *req);
+void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid);
static inline u32 nvmet_rw_len(struct nvmet_req *req)
{