Revert r267961, r267973:

These changes prevent sysctl(8) from returning proper output,
such as:

 1) no output from sysctl(8)
 2) erroneously returning ENOMEM with tools like truss(1)
    or uname(1)
 truss: can not get etype: Cannot allocate memory

5 files changed, 20 insertions, 12 deletions

diff --git a/sys/cam/scsi/scsi_cd.c b/sys/cam/scsi/scsi_cd.c
index 47a5a438d294..81c29a6fb54c 100644
--- a/sys/cam/scsi/scsi_cd.c
+++ b/sys/cam/scsi/scsi_cd.c
@@ -277,12 +277,15 @@ static int cd_retry_count = CD_DEFAULT_RETRY;
 static int cd_timeout = CD_DEFAULT_TIMEOUT;
 
 static SYSCTL_NODE(_kern_cam, OID_AUTO, cd, CTLFLAG_RD, 0, "CAM CDROM driver");
-SYSCTL_INT(_kern_cam_cd, OID_AUTO, poll_period, CTLFLAG_RWTUN,
+SYSCTL_INT(_kern_cam_cd, OID_AUTO, poll_period, CTLFLAG_RW,
            &cd_poll_period, 0, "Media polling period in seconds");
-SYSCTL_INT(_kern_cam_cd, OID_AUTO, retry_count, CTLFLAG_RWTUN,
+TUNABLE_INT("kern.cam.cd.poll_period", &cd_poll_period);
+SYSCTL_INT(_kern_cam_cd, OID_AUTO, retry_count, CTLFLAG_RW,
            &cd_retry_count, 0, "Normal I/O retry count");
-SYSCTL_INT(_kern_cam_cd, OID_AUTO, timeout, CTLFLAG_RWTUN,
+TUNABLE_INT("kern.cam.cd.retry_count", &cd_retry_count);
+SYSCTL_INT(_kern_cam_cd, OID_AUTO, timeout, CTLFLAG_RW,
 	   &cd_timeout, 0, "Timeout, in us, for read operations");
+TUNABLE_INT("kern.cam.cd.timeout", &cd_timeout);
 
 static MALLOC_DEFINE(M_SCSICD, "scsi_cd", "scsi_cd buffers");
 
diff --git a/sys/cam/scsi/scsi_da.c b/sys/cam/scsi/scsi_da.c
index 0b1f8d595e36..1a0757702035 100644
--- a/sys/cam/scsi/scsi_da.c
+++ b/sys/cam/scsi/scsi_da.c
@@ -1188,14 +1188,18 @@ static int da_send_ordered = DA_DEFAULT_SEND_ORDERED;
 
 static SYSCTL_NODE(_kern_cam, OID_AUTO, da, CTLFLAG_RD, 0,
             "CAM Direct Access Disk driver");
-SYSCTL_INT(_kern_cam_da, OID_AUTO, poll_period, CTLFLAG_RWTUN,
+SYSCTL_INT(_kern_cam_da, OID_AUTO, poll_period, CTLFLAG_RW,
            &da_poll_period, 0, "Media polling period in seconds");
-SYSCTL_INT(_kern_cam_da, OID_AUTO, retry_count, CTLFLAG_RWTUN,
+TUNABLE_INT("kern.cam.da.poll_period", &da_poll_period);
+SYSCTL_INT(_kern_cam_da, OID_AUTO, retry_count, CTLFLAG_RW,
            &da_retry_count, 0, "Normal I/O retry count");
-SYSCTL_INT(_kern_cam_da, OID_AUTO, default_timeout, CTLFLAG_RWTUN,
+TUNABLE_INT("kern.cam.da.retry_count", &da_retry_count);
+SYSCTL_INT(_kern_cam_da, OID_AUTO, default_timeout, CTLFLAG_RW,
            &da_default_timeout, 0, "Normal I/O timeout (in seconds)");
-SYSCTL_INT(_kern_cam_da, OID_AUTO, send_ordered, CTLFLAG_RWTUN,
+TUNABLE_INT("kern.cam.da.default_timeout", &da_default_timeout);
+SYSCTL_INT(_kern_cam_da, OID_AUTO, send_ordered, CTLFLAG_RW,
            &da_send_ordered, 0, "Send Ordered Tags");
+TUNABLE_INT("kern.cam.da.send_ordered", &da_send_ordered);
 
 /*
  * DA_ORDEREDTAG_INTERVAL determines how often, relative
diff --git a/sys/cam/scsi/scsi_enc_safte.c b/sys/cam/scsi/scsi_enc_safte.c
index 89f70a5ada23..8282d013bb58 100644
--- a/sys/cam/scsi/scsi_enc_safte.c
+++ b/sys/cam/scsi/scsi_enc_safte.c
@@ -226,8 +226,9 @@ static char *safte_2little = "Too Little Data Returned (%d) at line %d\n";
 
 int emulate_array_devices = 1;
 SYSCTL_DECL(_kern_cam_enc);
-SYSCTL_INT(_kern_cam_enc, OID_AUTO, emulate_array_devices, CTLFLAG_RWTUN,
+SYSCTL_INT(_kern_cam_enc, OID_AUTO, emulate_array_devices, CTLFLAG_RW,
            &emulate_array_devices, 0, "Emulate Array Devices for SAF-TE");
+TUNABLE_INT("kern.cam.enc.emulate_array_devices", &emulate_array_devices);
 
 static int
 safte_fill_read_buf_io(enc_softc_t *enc, struct enc_fsm_state *state,
diff --git a/sys/cam/scsi/scsi_sa.c b/sys/cam/scsi/scsi_sa.c
index 16b7b149036f..c1cd0f0bfdf6 100644
--- a/sys/cam/scsi/scsi_sa.c
+++ b/sys/cam/scsi/scsi_sa.c
@@ -445,10 +445,9 @@ static int sa_allow_io_split = SA_DEFAULT_IO_SPLIT;
  * is bad behavior, because it hides the true tape block size from the
  * application.
  */
+TUNABLE_INT("kern.cam.sa.allow_io_split", &sa_allow_io_split);
 static SYSCTL_NODE(_kern_cam, OID_AUTO, sa, CTLFLAG_RD, 0,
 		  "CAM Sequential Access Tape Driver");
-SYSCTL_INT(_kern_cam_sa, OID_AUTO, allow_io_split, CTLFLAG_RDTUN,
-    &sa_allow_io_split, 0, "Default I/O split value");
 
 static struct periph_driver sadriver =
 {
@@ -1495,7 +1494,7 @@ sasysctlinit(void *context, int pending)
 		goto bailout;
 
 	SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
-	    OID_AUTO, "allow_io_split", CTLTYPE_INT | CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 
+	    OID_AUTO, "allow_io_split", CTLTYPE_INT | CTLFLAG_RDTUN, 
 	    &softc->allow_io_split, 0, "Allow Splitting I/O");
 	SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
 	    OID_AUTO, "maxio", CTLTYPE_INT | CTLFLAG_RD, 
diff --git a/sys/cam/scsi/scsi_xpt.c b/sys/cam/scsi/scsi_xpt.c
index 42b8774fd88a..942f7121cf5a 100644
--- a/sys/cam/scsi/scsi_xpt.c
+++ b/sys/cam/scsi/scsi_xpt.c
@@ -78,8 +78,9 @@ struct scsi_quirk_entry {
 #define SCSI_QUIRK(dev)	((struct scsi_quirk_entry *)((dev)->quirk))
 
 static int cam_srch_hi = 0;
+TUNABLE_INT("kern.cam.cam_srch_hi", &cam_srch_hi);
 static int sysctl_cam_search_luns(SYSCTL_HANDLER_ARGS);
-SYSCTL_PROC(_kern_cam, OID_AUTO, cam_srch_hi, CTLTYPE_INT | CTLFLAG_RWTUN, 0, 0,
+SYSCTL_PROC(_kern_cam, OID_AUTO, cam_srch_hi, CTLTYPE_INT|CTLFLAG_RW, 0, 0,
     sysctl_cam_search_luns, "I",
     "allow search above LUN 7 for SCSI3 and greater devices");