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Differential D14633 Diff 41107 sys/i386/i386/sys_machdep.c

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sys/i386/i386/sys_machdep.c

Show First 20 Lines • Show All 288 Lines • ▼ Show 20 Lines struct soft_segment_descriptor ssd = {
SDT_SYS386TSS, /* segment type */ SDT_SYS386TSS, /* segment type */
0, /* priority level */ 0, /* priority level */
1, /* descriptor present */ 1, /* descriptor present */
0, 0, 0, 0,
0, /* default 32 size */ 0, /* default 32 size */
0 /* granularity */ 0 /* granularity */
}; };
ext = (struct pcb_ext *)kmem_malloc(kernel_arena, ctob(IOPAGES+1), ext = pmap_trm_alloc(ctob(IOPAGES + 1), M_WAITOK | M_ZERO);
M_WAITOK | M_ZERO);
/* -16 is so we can convert a trapframe into vm86trapframe inplace */ /* -16 is so we can convert a trapframe into vm86trapframe inplace */
ext->ext_tss.tss_esp0 = (vm_offset_t)td->td_pcb - 16;
ext->ext_tss.tss_ss0 = GSEL(GDATA_SEL, SEL_KPL); ext->ext_tss.tss_ss0 = GSEL(GDATA_SEL, SEL_KPL);
/* /*
* The last byte of the i/o map must be followed by an 0xff byte. * The last byte of the i/o map must be followed by an 0xff byte.
* We arbitrarily allocate 16 bytes here, to keep the starting * We arbitrarily allocate 16 bytes here, to keep the starting
* address on a doubleword boundary. * address on a doubleword boundary.
*/ */
offset = PAGE_SIZE - 16; offset = PAGE_SIZE - 16;
ext->ext_tss.tss_ioopt = ext->ext_tss.tss_ioopt =
Show All 9 Linesi386_extend_pcb(struct thread *td)
ssd.ssd_limit -= ((unsigned)&ext->ext_tss - (unsigned)ext); ssd.ssd_limit -= ((unsigned)&ext->ext_tss - (unsigned)ext);
ssdtosd(&ssd, &ext->ext_tssd); ssdtosd(&ssd, &ext->ext_tssd);
KASSERT(td == curthread, ("giving TSS to !curthread")); KASSERT(td == curthread, ("giving TSS to !curthread"));
KASSERT(td->td_pcb->pcb_ext == 0, ("already have a TSS!")); KASSERT(td->td_pcb->pcb_ext == 0, ("already have a TSS!"));
/* Switch to the new TSS. */ /* Switch to the new TSS. */
critical_enter(); critical_enter();
ext->ext_tss.tss_esp0 = PCPU_GET(trampstk);
td->td_pcb->pcb_ext = ext; td->td_pcb->pcb_ext = ext;
PCPU_SET(private_tss, 1); PCPU_SET(private_tss, 1);
*PCPU_GET(tss_gdt) = ext->ext_tssd; *PCPU_GET(tss_gdt) = ext->ext_tssd;
ltr(GSEL(GPROC0_SEL, SEL_KPL)); ltr(GSEL(GPROC0_SEL, SEL_KPL));
critical_exit(); critical_exit();
return 0; return 0;
} }
▲ Show 20 Lines • Show All 118 Lines • ▼ Show 20 Lines
{ {
struct proc_ldt *pldt, *new_ldt; struct proc_ldt *pldt, *new_ldt;
mtx_assert(&dt_lock, MA_OWNED); mtx_assert(&dt_lock, MA_OWNED);
mtx_unlock_spin(&dt_lock); mtx_unlock_spin(&dt_lock);
new_ldt = malloc(sizeof(struct proc_ldt), M_SUBPROC, M_WAITOK); new_ldt = malloc(sizeof(struct proc_ldt), M_SUBPROC, M_WAITOK);
new_ldt->ldt_len = len = NEW_MAX_LD(len); new_ldt->ldt_len = len = NEW_MAX_LD(len);
new_ldt->ldt_base = (caddr_t)kmem_malloc(kernel_arena, new_ldt->ldt_base = pmap_trm_alloc(len * sizeof(union descriptor),
len * sizeof(union descriptor), M_WAITOK | M_ZERO); M_WAITOK | M_ZERO);
new_ldt->ldt_refcnt = 1; new_ldt->ldt_refcnt = 1;
new_ldt->ldt_active = 0; new_ldt->ldt_active = 0;
mtx_lock_spin(&dt_lock); mtx_lock_spin(&dt_lock);
gdt_segs[GUSERLDT_SEL].ssd_base = (unsigned)new_ldt->ldt_base; gdt_segs[GUSERLDT_SEL].ssd_base = (unsigned)new_ldt->ldt_base;
gdt_segs[GUSERLDT_SEL].ssd_limit = len * sizeof(union descriptor) - 1; gdt_segs[GUSERLDT_SEL].ssd_limit = len * sizeof(union descriptor) - 1;
ssdtosd(&gdt_segs[GUSERLDT_SEL], &new_ldt->ldt_sd); ssdtosd(&gdt_segs[GUSERLDT_SEL], &new_ldt->ldt_sd);
if ((pldt = mdp->md_ldt) != NULL) { if ((pldt = mdp->md_ldt) != NULL) {
if (len > pldt->ldt_len) if (len > pldt->ldt_len)
len = pldt->ldt_len; len = pldt->ldt_len;
bcopy(pldt->ldt_base, new_ldt->ldt_base, bcopy(pldt->ldt_base, new_ldt->ldt_base,
len * sizeof(union descriptor)); len * sizeof(union descriptor));
} else } else
bcopy(ldt, new_ldt->ldt_base, sizeof(ldt)); bcopy(ldt, new_ldt->ldt_base, sizeof(union descriptor) * NLDT);
return (new_ldt); return (new_ldt);
} }
/* /*
* Must be called with dt_lock held. Returns with dt_lock unheld. * Must be called with dt_lock held. Returns with dt_lock unheld.
*/ */
void void
Show All 20 Lines
void void
user_ldt_deref(struct proc_ldt *pldt) user_ldt_deref(struct proc_ldt *pldt)
{ {
mtx_assert(&dt_lock, MA_OWNED); mtx_assert(&dt_lock, MA_OWNED);
if (--pldt->ldt_refcnt == 0) { if (--pldt->ldt_refcnt == 0) {
mtx_unlock_spin(&dt_lock); mtx_unlock_spin(&dt_lock);
kmem_free(kernel_arena, (vm_offset_t)pldt->ldt_base, pmap_trm_free(pldt->ldt_base, pldt->ldt_len *
pldt->ldt_len * sizeof(union descriptor)); sizeof(union descriptor));
free(pldt, M_SUBPROC); free(pldt, M_SUBPROC);
} else } else
mtx_unlock_spin(&dt_lock); mtx_unlock_spin(&dt_lock);
} }
/* /*
* Note for the authors of compat layers (linux, etc): copyout() in * Note for the authors of compat layers (linux, etc): copyout() in
* the function below is not a problem since it presents data in * the function below is not a problem since it presents data in
▲ Show 20 Lines • Show All 239 Lines • ▼ Show 20 Lines if ((pldt = mdp->md_ldt) == NULL || len > pldt->ldt_len) {
if (pldt != NULL) { if (pldt != NULL) {
if (new_ldt->ldt_len <= pldt->ldt_len) { if (new_ldt->ldt_len <= pldt->ldt_len) {
/* /*
* We just lost the race for allocation, so * We just lost the race for allocation, so
* free the new object and return. * free the new object and return.
*/ */
mtx_unlock_spin(&dt_lock); mtx_unlock_spin(&dt_lock);
kmem_free(kernel_arena, pmap_trm_free(new_ldt->ldt_base,
(vm_offset_t)new_ldt->ldt_base,
new_ldt->ldt_len * sizeof(union descriptor)); new_ldt->ldt_len * sizeof(union descriptor));
free(new_ldt, M_SUBPROC); free(new_ldt, M_SUBPROC);
mtx_lock_spin(&dt_lock); mtx_lock_spin(&dt_lock);
return (0); return (0);
} }
/* /*
* We have to substitute the current LDT entry for * We have to substitute the current LDT entry for
Show All 16 Lines#ifdef SMP
mtx_unlock_spin(&dt_lock); mtx_unlock_spin(&dt_lock);
smp_rendezvous(NULL, set_user_ldt_rv, NULL, smp_rendezvous(NULL, set_user_ldt_rv, NULL,
td->td_proc->p_vmspace); td->td_proc->p_vmspace);
#else #else
set_user_ldt_locked(&td->td_proc->p_md); set_user_ldt_locked(&td->td_proc->p_md);
mtx_unlock_spin(&dt_lock); mtx_unlock_spin(&dt_lock);
#endif #endif
if (old_ldt_base != NULL_LDT_BASE) { if (old_ldt_base != NULL_LDT_BASE) {
kmem_free(kernel_arena, (vm_offset_t)old_ldt_base, pmap_trm_free(old_ldt_base, old_ldt_len *
old_ldt_len * sizeof(union descriptor)); sizeof(union descriptor));
free(new_ldt, M_SUBPROC); free(new_ldt, M_SUBPROC);
} }
mtx_lock_spin(&dt_lock); mtx_lock_spin(&dt_lock);
} }
return (0); return (0);
} }