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- Remove somewhat bogus handling of the Giant mutex in the vm86 code.

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- Add a vm86pcb_lock mutex that is used to lock the vm86pcb used when
  making a vm86 call.
This commit is contained in:
John Baldwin 2000-10-05 20:27:45 +00:00
parent bd57768e0f
commit 1219828400
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=66691
2 changed files with 13 additions and 6 deletions
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14
sys/i386/i386/vm86.c
View File

@ -40,6 +40,7 @@
#include <sys/user.h> #include <sys/user.h>
#include <machine/md_var.h> #include <machine/md_var.h>
#include <machine/mutex.h>
#include <machine/pcb_ext.h> /* pcb.h included via sys/user.h */ #include <machine/pcb_ext.h> /* pcb.h included via sys/user.h */
#include <machine/psl.h> #include <machine/psl.h>
#include <machine/specialreg.h> #include <machine/specialreg.h>
@ -49,6 +50,8 @@ extern int i386_extend_pcb __P((struct proc *));
extern int vm86pa; extern int vm86pa;
extern struct pcb *vm86pcb; extern struct pcb *vm86pcb;
static struct mtx vm86pcb_lock;
extern int vm86_bioscall(struct vm86frame *); extern int vm86_bioscall(struct vm86frame *);
extern void vm86_biosret(struct vm86frame *); extern void vm86_biosret(struct vm86frame *);
@ -423,6 +426,8 @@ vm86_initialize(void)
pcb = &vml->vml_pcb; pcb = &vml->vml_pcb;
ext = &vml->vml_ext; ext = &vml->vml_ext;
mtx_init(&vm86pcb_lock, "vm86pcb lock", MTX_DEF);
bzero(pcb, sizeof(struct pcb)); bzero(pcb, sizeof(struct pcb));
pcb->new_ptd = vm86pa | PG_V | PG_RW | PG_U; pcb->new_ptd = vm86pa | PG_V | PG_RW | PG_U;
pcb->vm86_frame = vm86paddr - sizeof(struct vm86frame); pcb->vm86_frame = vm86paddr - sizeof(struct vm86frame);
@ -565,11 +570,16 @@ vm86_trap(struct vm86frame *vmf)
int int
vm86_intcall(int intnum, struct vm86frame *vmf) vm86_intcall(int intnum, struct vm86frame *vmf)
{ {
int retval;
if (intnum < 0 || intnum > 0xff) if (intnum < 0 || intnum > 0xff)
return (EINVAL); return (EINVAL);
vmf->vmf_trapno = intnum; vmf->vmf_trapno = intnum;
return (vm86_bioscall(vmf)); mtx_enter(&vm86pcb_lock, MTX_DEF);
retval = vm86_bioscall(vmf);
mtx_exit(&vm86pcb_lock, MTX_DEF);
return (retval);
} }
/* /*
@ -596,7 +606,9 @@ vm86_datacall(intnum, vmf, vmc)
} }
vmf->vmf_trapno = intnum; vmf->vmf_trapno = intnum;
mtx_enter(&vm86pcb_lock, MTX_DEF);
retval = vm86_bioscall(vmf); retval = vm86_bioscall(vmf);
mtx_exit(&vm86pcb_lock, MTX_DEF);
for (i = 0; i < vmc->npages; i++) { for (i = 0; i < vmc->npages; i++) {
entry = vmc->pmap[i].pte_num; entry = vmc->pmap[i].pte_num;

5
sys/i386/i386/vm86bios.s
View File

@ -62,10 +62,6 @@ ENTRY(vm86_bioscall)
pushl %edi pushl %edi
pushl %gs pushl %gs
pushl %edx
call __mtx_enter_giant_def /* Get global lock */
popl %edx
#if NNPX > 0 #if NNPX > 0
movl _curproc,%ecx movl _curproc,%ecx
cmpl %ecx,_npxproc /* do we need to save fp? */ cmpl %ecx,_npxproc /* do we need to save fp? */
@ -135,7 +131,6 @@ ENTRY(vm86_bioscall)
*/ */
subl $4,%esp /* dummy unit */ subl $4,%esp /* dummy unit */
incb _intr_nesting_level incb _intr_nesting_level
call __mtx_exit_giant_def
MEXITCOUNT MEXITCOUNT
jmp _doreti jmp _doreti