svn commit: r284918 - in head/sys/i386: i386 include

[Konstantin Belousov]

Author: kib
Date: Mon Jun 29 06:59:08 2015
New Revision: 284918
URL: https://svnweb.freebsd.org/changeset/base/284918

Log:
  Reduce code duplication.  Add helper fill_based_sd(9) which creates a
  based user data descriptor covering whole VA.
  
  Sponsored by:	The FreeBSD Foundation
  MFC after:	2 weeks

Modified:
  head/sys/i386/i386/sys_machdep.c
  head/sys/i386/include/md_var.h

Modified: head/sys/i386/i386/sys_machdep.c
==============================================================================
--- head/sys/i386/i386/sys_machdep.c	Mon Jun 29 00:30:30 2015	(r284917)
+++ head/sys/i386/i386/sys_machdep.c	Mon Jun 29 06:59:08 2015	(r284918)
@@ -74,6 +74,22 @@ static int i386_set_ldt_data(struct thre
 	union descriptor *descs);
 static int i386_ldt_grow(struct thread *td, int len);
 
+void
+fill_based_sd(struct segment_descriptor *sdp, uint32_t base)
+{
+
+	sdp->sd_lobase = base & 0xffffff;
+	sdp->sd_hibase = (base >> 24) & 0xff;
+	sdp->sd_lolimit = 0xffff;	/* 4GB limit, wraps around */
+	sdp->sd_hilimit = 0xf;
+	sdp->sd_type = SDT_MEMRWA;
+	sdp->sd_dpl = SEL_UPL;
+	sdp->sd_p = 1;
+	sdp->sd_xx = 0;
+	sdp->sd_def32 = 1;
+	sdp->sd_gran = 1;
+}
+
 #ifndef _SYS_SYSPROTO_H_
 struct sysarch_args {
 	int op;
@@ -188,23 +204,14 @@ sysarch(td, uap)
 		break;
 	case I386_SET_FSBASE:
 		error = copyin(uap->parms, &base, sizeof(base));
-		if (!error) {
+		if (error == 0) {
 			/*
 			 * Construct a descriptor and store it in the pcb for
 			 * the next context switch.  Also store it in the gdt
 			 * so that the load of tf_fs into %fs will activate it
 			 * at return to userland.
 			 */
-			sd.sd_lobase = base & 0xffffff;
-			sd.sd_hibase = (base >> 24) & 0xff;
-			sd.sd_lolimit = 0xffff;	/* 4GB limit, wraps around */
-			sd.sd_hilimit = 0xf;
-			sd.sd_type  = SDT_MEMRWA;
-			sd.sd_dpl   = SEL_UPL;
-			sd.sd_p     = 1;
-			sd.sd_xx    = 0;
-			sd.sd_def32 = 1;
-			sd.sd_gran  = 1;
+			fill_based_sd(&sd, base);
 			critical_enter();
 			td->td_pcb->pcb_fsd = sd;
 			PCPU_GET(fsgs_gdt)[0] = sd;
@@ -219,23 +226,13 @@ sysarch(td, uap)
 		break;
 	case I386_SET_GSBASE:
 		error = copyin(uap->parms, &base, sizeof(base));
-		if (!error) {
+		if (error == 0) {
 			/*
 			 * Construct a descriptor and store it in the pcb for
 			 * the next context switch.  Also store it in the gdt
 			 * because we have to do a load_gs() right now.
 			 */
-			sd.sd_lobase = base & 0xffffff;
-			sd.sd_hibase = (base >> 24) & 0xff;
-
-			sd.sd_lolimit = 0xffff;	/* 4GB limit, wraps around */
-			sd.sd_hilimit = 0xf;
-			sd.sd_type  = SDT_MEMRWA;
-			sd.sd_dpl   = SEL_UPL;
-			sd.sd_p     = 1;
-			sd.sd_xx    = 0;
-			sd.sd_def32 = 1;
-			sd.sd_gran  = 1;
+			fill_based_sd(&sd, base);
 			critical_enter();
 			td->td_pcb->pcb_gsd = sd;
 			PCPU_GET(fsgs_gdt)[1] = sd;

Modified: head/sys/i386/include/md_var.h
==============================================================================
--- head/sys/i386/include/md_var.h	Mon Jun 29 00:30:30 2015	(r284917)
+++ head/sys/i386/include/md_var.h	Mon Jun 29 06:59:08 2015	(r284918)
@@ -94,6 +94,7 @@ struct	reg;
 struct	fpreg;
 struct  dbreg;
 struct	dumperinfo;
+struct	segment_descriptor;
 
 void	*alloc_fpusave(int flags);
 void	bcopyb(const void *from, void *to, size_t len);
@@ -114,6 +115,7 @@ void	dump_add_page(vm_paddr_t);
 void	dump_drop_page(vm_paddr_t);
 void	finishidentcpu(void);
 void	fillw(int /*u_short*/ pat, void *base, size_t cnt);
+void	fill_based_sd(struct segment_descriptor *sdp, uint32_t base);
 void	initializecpu(void);
 void	initializecpucache(void);
 void	i686_pagezero(void *addr);