nvme: apply user-specified timeout via transport handle

The --timeout / -t flag is parsed into nvme_args.timeout but was only
honored by format-nvm and admin-passthru. All other commands left
cmd.timeout_ms at 0 (set by nvme_init_*() helpers), silently falling
back to the kernel's admin_timeout (60s).

Rather than adding cmd.timeout_ms assignments at every call site, set
the timeout once on the transport handle in parse_and_open() and apply
it in libnvme_submit_admin_passthru() and libnvme_submit_io_passthru()
when the command's own timeout_ms is 0. Commands that set a non-zero
timeout_ms (e.g. format's 600s default) are unaffected.

This covers all built-in commands, all vendor plugins, and all internal
libnvme callers (nvme-cmds.c, tree.c, fabrics.c) without requiring
per-call-site changes.

libnvme changes:
  - Add __u32 timeout field to struct libnvme_transport_handle
  - Add libnvme_transport_handle_set_timeout() public API
  - Apply handle timeout in submit_admin_passthru/submit_io_passthru
  - Export new symbol in LIBNVME_4 version section

Signed-off-by: Nick Wolff <[email protected]>
Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Author: darkfiberiru

libnvme/src/libnvme.ld

@@ -196,3 +196,8 @@ LIBNVME_3 {
 	local:
 		*;
 };
+
+LIBNVME_4 {
+	global:
+		libnvme_transport_handle_set_timeout;
+} LIBNVME_3;

libnvme/src/nvme/ioctl.c

@@ -193,6 +193,9 @@ static int libnvme_submit_passthru64(struct libnvme_transport_handle *hdl,
 __public int libnvme_submit_io_passthru(struct libnvme_transport_handle *hdl,
 		struct libnvme_passthru_cmd *cmd)
 {
+	if (!cmd->timeout_ms && hdl->timeout)
+		cmd->timeout_ms = hdl->timeout;
+
 	if (hdl->ioctl_io64)
 		return libnvme_submit_passthru64(hdl,
 			LIBNVME_IOCTL_IO64_CMD, cmd);
@@ -202,6 +205,9 @@ __public int libnvme_submit_io_passthru(struct libnvme_transport_handle *hdl,
 __public int libnvme_submit_admin_passthru(struct libnvme_transport_handle *hdl,
 		struct libnvme_passthru_cmd *cmd)
 {
+	if (!cmd->timeout_ms && hdl->timeout)
+		cmd->timeout_ms = hdl->timeout;
+
 	switch (hdl->type) {
 	case LIBNVME_TRANSPORT_HANDLE_TYPE_DIRECT:
 		if (hdl->ioctl_admin64)

libnvme/src/nvme/lib.c

@@ -137,6 +137,12 @@ __public void libnvme_transport_handle_set_decide_retry(struct libnvme_transport
 		hdl->decide_retry = __libnvme_decide_retry;
 }
 
+__public void libnvme_transport_handle_set_timeout(
+		struct libnvme_transport_handle *hdl, __u32 timeout_ms)
+{
+	hdl->timeout = timeout_ms;
+}
+
 static int __nvme_transport_handle_open_direct(
 		struct libnvme_transport_handle *hdl, const char *devname)
 {

libnvme/src/nvme/lib.h

@@ -216,6 +216,19 @@ void libnvme_transport_handle_set_decide_retry(
 		bool (*decide_retry)(struct libnvme_transport_handle *hdl,
 				struct libnvme_passthru_cmd *cmd, int err));
 
+/**
+ * libnvme_transport_handle_set_timeout() - Set the default command timeout
+ * @hdl:	Transport handle to configure
+ * @timeout_ms:	Timeout in milliseconds. A value of 0 means use the kernel
+ *		default (NVME_DEFAULT_IOCTL_TIMEOUT).
+ *
+ * Sets a default timeout that is applied to every passthrough command
+ * submitted through @hdl when the command's own timeout_ms field is 0.
+ * Commands that set a non-zero timeout_ms override this default.
+ */
+void libnvme_transport_handle_set_timeout(
+		struct libnvme_transport_handle *hdl, __u32 timeout_ms);
+
 /**
  * libnvme_set_probe_enabled() - enable/disable the probe for new MI endpoints
  * @ctx:	&struct libnvme_global_ctx object

libnvme/src/nvme/private.h

@@ -150,6 +150,8 @@ struct libnvme_transport_handle {
 	bool (*decide_retry)(struct libnvme_transport_handle *hdl,
 			struct libnvme_passthru_cmd *cmd, int err);
 
+	__u32 timeout;
+
 	/* direct */
 	int fd;
 	struct stat stat;

nvme.c

@@ -381,6 +381,9 @@ int parse_and_open(struct libnvme_global_ctx **ctx,
 	libnvme_transport_handle_set_submit_exit(hdl_new , nvme_submit_exit);
 	libnvme_transport_handle_set_decide_retry(hdl_new, nvme_decide_retry);
 	libnvme_set_dry_run(ctx_new, argconfig_parse_seen(opts, "dry-run"));
+	if (argconfig_parse_seen(opts, "timeout"))
+		libnvme_transport_handle_set_timeout(hdl_new,
+						     nvme_args.timeout);
 
 	*ctx = ctx_new;
 	*hdl = hdl_new;