Differential D14633 Diff 40315 sys/i386/i386/vm_machdep.c

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sys/i386/i386/vm_machdep.c

Show First 20 Lines • Show All 211 Lines • ▼ Show 20 Lines	cpu_fork(struct thread td1, struct proc p2, struct thread *td2, int flags)
/* Point mdproc and then copy over td1's contents */		/* Point mdproc and then copy over td1's contents */
mdp2 = &p2->p_md;		mdp2 = &p2->p_md;
bcopy(&p1->p_md, mdp2, sizeof(*mdp2));		bcopy(&p1->p_md, mdp2, sizeof(*mdp2));

/*		/*
* Create a new fresh stack for the new process.		* Create a new fresh stack for the new process.
* Copy the trap frame for the return to user mode as if from a		* Copy the trap frame for the return to user mode as if from a
* syscall. This copies most of the user mode register values.		* syscall. This copies most of the user mode register values.
* The -16 is so we can expand the trapframe if we go to vm86.		* The -VM86_STACK_SPACE (-16) is so we can expand the trapframe
		* if we go to vm86.
*/		*/
td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1;		td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb -
		VM86_STACK_SPACE) - 1;
bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe));		bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe));

td2->td_frame->tf_eax = 0; /* Child returns zero */		td2->td_frame->tf_eax = 0; /* Child returns zero */
td2->td_frame->tf_eflags &= ~PSL_C; /* success */		td2->td_frame->tf_eflags &= ~PSL_C; /* success */
td2->td_frame->tf_edx = 1;		td2->td_frame->tf_edx = 1;

/*		/*
* If the parent process has the trap bit set (i.e. a debugger had		* If the parent process has the trap bit set (i.e. a debugger had
Show All 15 Lines
#else		#else
pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir);		pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir);
#endif		#endif
pcb2->pcb_edi = 0;		pcb2->pcb_edi = 0;
pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */		pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */
pcb2->pcb_ebp = 0;		pcb2->pcb_ebp = 0;
pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);		pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);
pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */		pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */
pcb2->pcb_eip = (int)fork_trampoline;		pcb2->pcb_eip = (int)fork_trampoline + setidt_disp;
/*-		/*-
* pcb2->pcb_dr*: cloned above.		* pcb2->pcb_dr*: cloned above.
* pcb2->pcb_savefpu: cloned above.		* pcb2->pcb_savefpu: cloned above.
* pcb2->pcb_flags: cloned above.		* pcb2->pcb_flags: cloned above.
* pcb2->pcb_onfault: cloned above (always NULL here?).		* pcb2->pcb_onfault: cloned above (always NULL here?).
* pcb2->pcb_gs: cloned above.		* pcb2->pcb_gs: cloned above.
* pcb2->pcb_ext: cleared below.		* pcb2->pcb_ext: cleared below.
*/		*/
▲ Show 20 Lines • Show All 89 Lines • ▼ Show 20 Lines	cpu_thread_clean(struct thread *td)

pcb = td->td_pcb;		pcb = td->td_pcb;
if (pcb->pcb_ext != NULL) {		if (pcb->pcb_ext != NULL) {
/* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */		/* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */
/*		/*
* XXX do we need to move the TSS off the allocated pages		* XXX do we need to move the TSS off the allocated pages
* before freeing them? (not done here)		* before freeing them? (not done here)
*/		*/
kmem_free(kernel_arena, (vm_offset_t)pcb->pcb_ext,		pmap_trm_free(pcb->pcb_ext, ctob(IOPAGES + 1));
ctob(IOPAGES + 1));
pcb->pcb_ext = NULL;		pcb->pcb_ext = NULL;
}		}
}		}

void		void
cpu_thread_swapin(struct thread *td)		cpu_thread_swapin(struct thread *td)
{		{
}		}

void		void
cpu_thread_swapout(struct thread *td)		cpu_thread_swapout(struct thread *td)
{		{
}		}

void		void
cpu_thread_alloc(struct thread *td)		cpu_thread_alloc(struct thread *td)
{		{
struct pcb *pcb;		struct pcb *pcb;
struct xstate_hdr *xhdr;		struct xstate_hdr *xhdr;

td->td_pcb = pcb = get_pcb_td(td);		td->td_pcb = pcb = get_pcb_td(td);
td->td_frame = (struct trapframe *)((caddr_t)pcb - 16) - 1;		td->td_frame = (struct trapframe *)((caddr_t)pcb -
		VM86_STACK_SPACE) - 1;
pcb->pcb_ext = NULL;		pcb->pcb_ext = NULL;
pcb->pcb_save = get_pcb_user_save_pcb(pcb);		pcb->pcb_save = get_pcb_user_save_pcb(pcb);
if (use_xsave) {		if (use_xsave) {
xhdr = (struct xstate_hdr *)(pcb->pcb_save + 1);		xhdr = (struct xstate_hdr *)(pcb->pcb_save + 1);
bzero(xhdr, sizeof(*xhdr));		bzero(xhdr, sizeof(*xhdr));
xhdr->xstate_bv = xsave_mask;		xhdr->xstate_bv = xsave_mask;
}		}
}		}
▲ Show 20 Lines • Show All 78 Lines • ▼ Show 20 Lines	cpu_copy_thread(struct thread td, struct thread td0)
* Set registers for trampoline to user mode. Leave space for the		* Set registers for trampoline to user mode. Leave space for the
* return address on stack. These are the kernel mode register values.		* return address on stack. These are the kernel mode register values.
*/		*/
pcb2->pcb_edi = 0;		pcb2->pcb_edi = 0;
pcb2->pcb_esi = (int)fork_return; /* trampoline arg */		pcb2->pcb_esi = (int)fork_return; /* trampoline arg */
pcb2->pcb_ebp = 0;		pcb2->pcb_ebp = 0;
pcb2->pcb_esp = (int)td->td_frame - sizeof(void ); / trampoline arg */		pcb2->pcb_esp = (int)td->td_frame - sizeof(void ); / trampoline arg */
pcb2->pcb_ebx = (int)td; /* trampoline arg */		pcb2->pcb_ebx = (int)td; /* trampoline arg */
pcb2->pcb_eip = (int)fork_trampoline;		pcb2->pcb_eip = (int)fork_trampoline + setidt_disp;
pcb2->pcb_gs = rgs();		pcb2->pcb_gs = rgs();
/*		/*
* If we didn't copy the pcb, we'd need to do the following registers:		* If we didn't copy the pcb, we'd need to do the following registers:
* pcb2->pcb_cr3: cloned above.		* pcb2->pcb_cr3: cloned above.
* pcb2->pcb_dr*: cloned above.		* pcb2->pcb_dr*: cloned above.
* pcb2->pcb_savefpu: cloned above.		* pcb2->pcb_savefpu: cloned above.
* pcb2->pcb_flags: cloned above.		* pcb2->pcb_flags: cloned above.
* pcb2->pcb_onfault: cloned above (always NULL here?).		* pcb2->pcb_onfault: cloned above (always NULL here?).
▲ Show 20 Lines • Show All 237 Lines • ▼ Show 20 Lines	sf_buf_map(struct sf_buf *sf, int flags)
* Update the sf_buf's virtual-to-physical mapping, flushing the		* Update the sf_buf's virtual-to-physical mapping, flushing the
* virtual address from the TLB. Since the reference count for		* virtual address from the TLB. Since the reference count for
* the sf_buf's old mapping was zero, that mapping is not		* the sf_buf's old mapping was zero, that mapping is not
* currently in use. Consequently, there is no need to exchange		* currently in use. Consequently, there is no need to exchange
* the old and new PTEs atomically, even under PAE.		* the old and new PTEs atomically, even under PAE.
*/		*/
ptep = vtopte(sf->kva);		ptep = vtopte(sf->kva);
opte = *ptep;		opte = *ptep;
*ptep = VM_PAGE_TO_PHYS(sf->m) \| pgeflag \| PG_RW \| PG_V \|		*ptep = VM_PAGE_TO_PHYS(sf->m) \| PG_RW \| PG_V \|
pmap_cache_bits(sf->m->md.pat_mode, 0);		pmap_cache_bits(sf->m->md.pat_mode, 0);

/*		/*
* Avoid unnecessary TLB invalidations: If the sf_buf's old		* Avoid unnecessary TLB invalidations: If the sf_buf's old
* virtual-to-physical mapping was not used, then any processor		* virtual-to-physical mapping was not used, then any processor
* that has invalidated the sf_buf's virtual address from its TLB		* that has invalidated the sf_buf's virtual address from its TLB
* since the last used mapping need not invalidate again.		* since the last used mapping need not invalidate again.
*/		*/
▲ Show 20 Lines • Show All 107 Lines • Show Last 20 Lines