Clean out the leftovers from the i386_set_gsbase() TLS conversion.

Like on libthr, there is an i386_set_gsbase() stub implementation here
to avoid libc.so.5 issues.  This should likely be a weak symbol and I
expect this will be fixed soon.

Approved by:	re

lib/libc/i386/gen/_set_tp.c

@@ -28,28 +28,11 @@
 
 #include <string.h>
 #include <stdint.h>
-#include <machine/segments.h>
 #include <machine/sysarch.h>
 
 void
 _set_tp(void *tp)
 {
-	union descriptor ldt;
-	int error, sel;
 
-	error = i386_set_gsbase(tp);
+	i386_set_gsbase(tp);
-	if (error == 0)
-		return;
-	memset(&ldt, 0, sizeof(ldt));
-	ldt.sd.sd_lolimit = 0xffff;	/* 4G limit */
-	ldt.sd.sd_lobase = ((uintptr_t)tp) & 0xffffff;
-	ldt.sd.sd_type = SDT_MEMRWA;
-	ldt.sd.sd_dpl = SEL_UPL;
-	ldt.sd.sd_p = 1;		/* present */
-	ldt.sd.sd_hilimit = 0xf;	/* 4G limit */
-	ldt.sd.sd_def32 = 1;		/* 32 bit */
-	ldt.sd.sd_gran = 1;		/* limit in pages */
-	ldt.sd.sd_hibase = (((uintptr_t)tp) >> 24) & 0xff;
-	sel = i386_set_ldt(LDT_AUTO_ALLOC, &ldt, 1);
-	__asm __volatile("movl %0,%%gs" : : "rm" ((sel << 3) | 7));
 }

lib/libkse/arch/i386/i386/pthread_md.c

@@ -30,7 +30,6 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/types.h>
 #include <machine/cpufunc.h>
-#include <machine/segments.h>
 #include <machine/sysarch.h>
 
 #include <unistd.h>
@@ -42,8 +41,6 @@ __FBSDID("$FreeBSD$");
 #include "rtld_tls.h"
 #include "pthread_md.h"
 
-int _thr_using_setbase;
-
 struct tcb *
 _tcb_ctor(struct pthread *thread, int initial)
 {
@@ -78,46 +75,14 @@ _tcb_dtor(struct tcb *tcb)
 struct kcb *
 _kcb_ctor(struct kse *kse)
 {
-	union descriptor ldt;
 	void *base;
 	struct kcb *kcb;
-	int error;
 
 	kcb = malloc(sizeof(struct kcb));
 	if (kcb != NULL) {
 		bzero(kcb, sizeof(struct kcb));
 		kcb->kcb_self = kcb;
 		kcb->kcb_kse = kse;
-		switch (_thr_using_setbase) {
-		case 1:	/* use i386_set_gsbase() in _kcb_set */
-			kcb->kcb_ldt = -1;
-			break;
-		case 0:	/* Untested, try the get/set_gsbase routines once */
-			error = i386_get_gsbase(&base);
-			if (error == 0) {
-				_thr_using_setbase = 1;
-				break;
-			}
-			/* fall through */
-		case 2:	/* Use the user_ldt code, we must have an old kernel */
-			_thr_using_setbase = 2;
-			ldt.sd.sd_hibase = (unsigned int)kcb >> 24;
-			ldt.sd.sd_lobase = (unsigned int)kcb & 0xFFFFFF;
-			ldt.sd.sd_hilimit = (sizeof(struct kcb) >> 16) & 0xF;
-			ldt.sd.sd_lolimit = sizeof(struct kcb) & 0xFFFF;
-			ldt.sd.sd_type = SDT_MEMRWA;
-			ldt.sd.sd_dpl = SEL_UPL;
-			ldt.sd.sd_p = 1;
-			ldt.sd.sd_xx = 0;
-			ldt.sd.sd_def32 = 1;
-			ldt.sd.sd_gran = 0;	/* no more than 1M */
-			kcb->kcb_ldt = i386_set_ldt(LDT_AUTO_ALLOC, &ldt, 1);
-			if (kcb->kcb_ldt < 0) {
-				free(kcb);
-				return (NULL);
-			}
-			break;
-		}
 	}
 	return (kcb);
 }
@@ -125,9 +90,12 @@ _kcb_ctor(struct kse *kse)
 void
 _kcb_dtor(struct kcb *kcb)
 {
-	if (kcb->kcb_ldt >= 0) {
-		i386_set_ldt(kcb->kcb_ldt, NULL, 1);
-		kcb->kcb_ldt = -1;	/* just in case */
-	}
 	free(kcb);
 }
+
+int
+i386_set_gsbase(void *addr)
+{
+
+	return (sysarch(I386_SET_GSBASE, &addr));
+}

lib/libkse/arch/i386/include/pthread_md.h

@@ -40,8 +40,6 @@
 extern int _thr_setcontext(mcontext_t *, intptr_t, intptr_t *);
 extern int _thr_getcontext(mcontext_t *);
 
-extern int _thr_using_setbase;
-
 #define	KSE_STACKSIZE		16384
 #define	DTV_OFFSET		offsetof(struct tcb, tcb_dtv)
 
@@ -60,7 +58,6 @@ struct pthread;
 struct kcb {
 	struct tcb		*kcb_curtcb;
 	struct kcb		*kcb_self;	/* self reference */
-	int			kcb_ldt;
 	struct kse		*kcb_kse;
 	struct kse_mailbox	kcb_kmbx;
 };
@@ -154,15 +151,7 @@ void		_kcb_dtor(struct kcb *);
 static __inline void
 _kcb_set(struct kcb *kcb)
 {
-	int val;
-
-	if (_thr_using_setbase == 1) {
 	i386_set_gsbase(kcb);
-	} else {
-		val = (kcb->kcb_ldt << 3) | 7;
-		__asm __volatile("movl %0, %%gs" : : "r" (val));
-	}
-
 }
 
 /* Get the current kcb. */

lib/libpthread/arch/i386/i386/pthread_md.c

@@ -30,7 +30,6 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/types.h>
 #include <machine/cpufunc.h>
-#include <machine/segments.h>
 #include <machine/sysarch.h>
 
 #include <unistd.h>
@@ -42,8 +41,6 @@ __FBSDID("$FreeBSD$");
 #include "rtld_tls.h"
 #include "pthread_md.h"
 
-int _thr_using_setbase;
-
 struct tcb *
 _tcb_ctor(struct pthread *thread, int initial)
 {
@@ -78,46 +75,14 @@ _tcb_dtor(struct tcb *tcb)
 struct kcb *
 _kcb_ctor(struct kse *kse)
 {
-	union descriptor ldt;
 	void *base;
 	struct kcb *kcb;
-	int error;
 
 	kcb = malloc(sizeof(struct kcb));
 	if (kcb != NULL) {
 		bzero(kcb, sizeof(struct kcb));
 		kcb->kcb_self = kcb;
 		kcb->kcb_kse = kse;
-		switch (_thr_using_setbase) {
-		case 1:	/* use i386_set_gsbase() in _kcb_set */
-			kcb->kcb_ldt = -1;
-			break;
-		case 0:	/* Untested, try the get/set_gsbase routines once */
-			error = i386_get_gsbase(&base);
-			if (error == 0) {
-				_thr_using_setbase = 1;
-				break;
-			}
-			/* fall through */
-		case 2:	/* Use the user_ldt code, we must have an old kernel */
-			_thr_using_setbase = 2;
-			ldt.sd.sd_hibase = (unsigned int)kcb >> 24;
-			ldt.sd.sd_lobase = (unsigned int)kcb & 0xFFFFFF;
-			ldt.sd.sd_hilimit = (sizeof(struct kcb) >> 16) & 0xF;
-			ldt.sd.sd_lolimit = sizeof(struct kcb) & 0xFFFF;
-			ldt.sd.sd_type = SDT_MEMRWA;
-			ldt.sd.sd_dpl = SEL_UPL;
-			ldt.sd.sd_p = 1;
-			ldt.sd.sd_xx = 0;
-			ldt.sd.sd_def32 = 1;
-			ldt.sd.sd_gran = 0;	/* no more than 1M */
-			kcb->kcb_ldt = i386_set_ldt(LDT_AUTO_ALLOC, &ldt, 1);
-			if (kcb->kcb_ldt < 0) {
-				free(kcb);
-				return (NULL);
-			}
-			break;
-		}
 	}
 	return (kcb);
 }
@@ -125,9 +90,12 @@ _kcb_ctor(struct kse *kse)
 void
 _kcb_dtor(struct kcb *kcb)
 {
-	if (kcb->kcb_ldt >= 0) {
-		i386_set_ldt(kcb->kcb_ldt, NULL, 1);
-		kcb->kcb_ldt = -1;	/* just in case */
-	}
 	free(kcb);
 }
+
+int
+i386_set_gsbase(void *addr)
+{
+
+	return (sysarch(I386_SET_GSBASE, &addr));
+}

lib/libpthread/arch/i386/include/pthread_md.h

@@ -40,8 +40,6 @@
 extern int _thr_setcontext(mcontext_t *, intptr_t, intptr_t *);
 extern int _thr_getcontext(mcontext_t *);
 
-extern int _thr_using_setbase;
-
 #define	KSE_STACKSIZE		16384
 #define	DTV_OFFSET		offsetof(struct tcb, tcb_dtv)
 
@@ -60,7 +58,6 @@ struct pthread;
 struct kcb {
 	struct tcb		*kcb_curtcb;
 	struct kcb		*kcb_self;	/* self reference */
-	int			kcb_ldt;
 	struct kse		*kcb_kse;
 	struct kse_mailbox	kcb_kmbx;
 };
@@ -154,15 +151,7 @@ void		_kcb_dtor(struct kcb *);
 static __inline void
 _kcb_set(struct kcb *kcb)
 {
-	int val;
-
-	if (_thr_using_setbase == 1) {
 	i386_set_gsbase(kcb);
-	} else {
-		val = (kcb->kcb_ldt << 3) | 7;
-		__asm __volatile("movl %0, %%gs" : : "r" (val));
-	}
-
 }
 
 /* Get the current kcb. */

libexec/rtld-elf/i386/reloc.c

@@ -327,8 +327,6 @@ void
 allocate_initial_tls(Obj_Entry *objs)
 {
     void* tls;
-    union descriptor ldt;
-    int error, sel;
 
     /*
      * Fix the size of the static TLS block by using the maximum
@@ -337,21 +335,7 @@ allocate_initial_tls(Obj_Entry *objs)
      */
     tls_static_space = tls_last_offset + RTLD_STATIC_TLS_EXTRA;
     tls = allocate_tls(objs, NULL, 2*sizeof(Elf_Addr), sizeof(Elf_Addr));
-    error = i386_set_gsbase(tls);
+    i386_set_gsbase(tls);
-    if (error < 0) {
-	memset(&ldt, 0, sizeof(ldt));
-	ldt.sd.sd_lolimit = 0xffff;	/* 4G limit */
-	ldt.sd.sd_lobase = ((Elf_Addr)tls) & 0xffffff;
-	ldt.sd.sd_type = SDT_MEMRWA;
-	ldt.sd.sd_dpl = SEL_UPL;
-	ldt.sd.sd_p = 1;		/* present */
-	ldt.sd.sd_hilimit = 0xf;	/* 4G limit */
-	ldt.sd.sd_def32 = 1;	/* 32 bit */
-	ldt.sd.sd_gran = 1;		/* limit in pages */
-	ldt.sd.sd_hibase = (((Elf_Addr)tls) >> 24) & 0xff;
-	sel = i386_set_ldt(LDT_AUTO_ALLOC, &ldt, 1);
-	__asm __volatile("movl %0,%%gs" : : "rm" ((sel << 3) | 7));
-    }
 }
 
 /* GNU ABI */