Ejemplo n.º 1
0
Archivo: bsd_vm.c Proyecto: Prajna/xnu
kern_return_t
vnode_pager_get_isSSD(
	memory_object_t		mem_obj,
	boolean_t		*isSSD)
{
	vnode_pager_t	vnode_object;

	if (mem_obj->mo_pager_ops != &vnode_pager_ops)
		return KERN_INVALID_ARGUMENT;

	vnode_object = vnode_pager_lookup(mem_obj);

	*isSSD = vnode_pager_isSSD(vnode_object->vnode_handle);
	return KERN_SUCCESS;
}
Ejemplo n.º 2
0
/*
 *	Routine:	macx_swapon
 *	Function:
 *		Syscall interface to add a file to backing store
 */
int
macx_swapon(
	struct macx_swapon_args *args)
{
	int			size = args->size;
	vnode_t			vp = (vnode_t)NULL; 
	struct nameidata 	nd, *ndp;
	register int		error;
	kern_return_t		kr;
	mach_port_t		backing_store;
	memory_object_default_t	default_pager;
	int			i;
	boolean_t		funnel_state;
	off_t			file_size;
	vfs_context_t		ctx = vfs_context_current();
	struct proc		*p =  current_proc();
	int			dp_cluster_size;


	AUDIT_MACH_SYSCALL_ENTER(AUE_SWAPON);
	AUDIT_ARG(value32, args->priority);

	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	ndp = &nd;

	if ((error = suser(kauth_cred_get(), 0)))
		goto swapon_bailout;

	/*
	 * Get a vnode for the paging area.
	 */
	NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
	       ((IS_64BIT_PROCESS(p)) ? UIO_USERSPACE64 : UIO_USERSPACE32),
	       (user_addr_t) args->filename, ctx);

	if ((error = namei(ndp)))
		goto swapon_bailout;
	nameidone(ndp);
	vp = ndp->ni_vp;

	if (vp->v_type != VREG) {
		error = EINVAL;
		goto swapon_bailout;
	}

	/* get file size */
	if ((error = vnode_size(vp, &file_size, ctx)) != 0)
		goto swapon_bailout;
#if CONFIG_MACF
	vnode_lock(vp);
	error = mac_system_check_swapon(vfs_context_ucred(ctx), vp);
	vnode_unlock(vp);
	if (error)
		goto swapon_bailout;
#endif

	/* resize to desired size if it's too small */
	if ((file_size < (off_t)size) && ((error = vnode_setsize(vp, (off_t)size, 0, ctx)) != 0))
		goto swapon_bailout;

#if CONFIG_PROTECT
	{
		/* initialize content protection keys manually */
		if ((error = cp_handle_vnop(vp, CP_WRITE_ACCESS, 0)) != 0) {
			goto swapon_bailout;
 		}
	}
#endif


	if (default_pager_init_flag == 0) {
		start_def_pager(NULL);
		default_pager_init_flag = 1;
	}

	/* add new backing store to list */
	i = 0;
	while(bs_port_table[i].vp != 0) {
		if(i == MAX_BACKING_STORE)
			break;
		i++;
	}
	if(i == MAX_BACKING_STORE) {
	   	error = ENOMEM;
		goto swapon_bailout;
	}

	/* remember the vnode. This vnode has namei() reference */
	bs_port_table[i].vp = vp;
	
	/*
	 * Look to see if we are already paging to this file.
	 */
	/* make certain the copy send of kernel call will work */
	default_pager = MEMORY_OBJECT_DEFAULT_NULL;
	kr = host_default_memory_manager(host_priv_self(), &default_pager, 0);
	if(kr != KERN_SUCCESS) {
	   error = EAGAIN;
	   bs_port_table[i].vp = 0;
	   goto swapon_bailout;
	}

#if CONFIG_EMBEDDED
	dp_cluster_size = 1 * PAGE_SIZE;
#else
	if ((dp_isssd = vnode_pager_isSSD(vp)) == TRUE) {
		/*
		 * keep the cluster size small since the
		 * seek cost is effectively 0 which means
		 * we don't care much about fragmentation
		 */
		dp_cluster_size = 2 * PAGE_SIZE;
	} else {
		/*
		 * use the default cluster size
		 */
		dp_cluster_size = 0;
	}
#endif
	kr = default_pager_backing_store_create(default_pager, 
					-1, /* default priority */
					dp_cluster_size,
					&backing_store);
	memory_object_default_deallocate(default_pager);

	if(kr != KERN_SUCCESS) {
	   error = ENOMEM;
	   bs_port_table[i].vp = 0;
	   goto swapon_bailout;
	}

	/* Mark this vnode as being used for swapfile */
	vnode_lock_spin(vp);
	SET(vp->v_flag, VSWAP);
	vnode_unlock(vp);

	/*
	 * NOTE: we are able to supply PAGE_SIZE here instead of
	 *	an actual record size or block number because:
	 *	a: we do not support offsets from the beginning of the
	 *		file (allowing for non page size/record modulo offsets.
	 *	b: because allow paging will be done modulo page size
	 */

	kr = default_pager_add_file(backing_store, (vnode_ptr_t) vp,
				PAGE_SIZE, (int)(file_size/PAGE_SIZE));
	if(kr != KERN_SUCCESS) {
	   bs_port_table[i].vp = 0;
	   if(kr == KERN_INVALID_ARGUMENT)
		error = EINVAL;
	   else 
		error = ENOMEM;

	   /* This vnode is not to be used for swapfile */
	   vnode_lock_spin(vp);
	   CLR(vp->v_flag, VSWAP);
	   vnode_unlock(vp);

	   goto swapon_bailout;
	}
	bs_port_table[i].bs = (void *)backing_store;
	error = 0;

	ubc_setthreadcred(vp, p, current_thread());

	/*
	 * take a long term reference on the vnode to keep
	 * vnreclaim() away from this vnode.
	 */
	vnode_ref(vp);

swapon_bailout:
	if (vp) {
		vnode_put(vp);
	}
	(void) thread_funnel_set(kernel_flock, FALSE);
	AUDIT_MACH_SYSCALL_EXIT(error);

	if (error)
		printf("macx_swapon FAILED - %d\n", error);
	else
		printf("macx_swapon SUCCESS\n");

	return(error);
}