vm_machdep.c revision 259335
1/*-
2 * Copyright (c) 1982, 1986 The Regents of the University of California.
3 * Copyright (c) 1989, 1990 William Jolitz
4 * Copyright (c) 1994 John Dyson
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * the Systems Programming Group of the University of Utah Computer
9 * Science Department, and William Jolitz.
10 *
11 * Redistribution and use in source and binary :forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgement:
21 *	This product includes software developed by the University of
22 *	California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 *    may be used to endorse or promote products derived from this software
25 *    without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 *	from: @(#)vm_machdep.c	7.3 (Berkeley) 5/13/91
40 *	Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
41 */
42
43#include <sys/cdefs.h>
44__FBSDID("$FreeBSD: stable/10/sys/arm/arm/vm_machdep.c 259335 2013-12-13 21:40:12Z ian $");
45
46#include <sys/param.h>
47#include <sys/systm.h>
48#include <sys/kernel.h>
49#include <sys/malloc.h>
50#include <sys/mbuf.h>
51#include <sys/proc.h>
52#include <sys/socketvar.h>
53#include <sys/sf_buf.h>
54#include <sys/syscall.h>
55#include <sys/sysctl.h>
56#include <sys/sysent.h>
57#include <sys/unistd.h>
58#include <machine/cpu.h>
59#include <machine/frame.h>
60#include <machine/pcb.h>
61#include <machine/sysarch.h>
62#include <sys/lock.h>
63#include <sys/mutex.h>
64
65#include <vm/vm.h>
66#include <vm/pmap.h>
67#include <vm/vm_extern.h>
68#include <vm/vm_kern.h>
69#include <vm/vm_page.h>
70#include <vm/vm_map.h>
71#include <vm/vm_param.h>
72#include <vm/vm_pageout.h>
73#include <vm/uma.h>
74#include <vm/uma_int.h>
75
76#include <machine/md_var.h>
77
78/*
79 * struct switchframe and trapframe must both be a multiple of 8
80 * for correct stack alignment.
81 */
82CTASSERT(sizeof(struct switchframe) == 24);
83CTASSERT(sizeof(struct trapframe) == 80);
84
85#ifndef ARM_USE_SMALL_ALLOC
86
87#ifndef NSFBUFS
88#define NSFBUFS		(512 + maxusers * 16)
89#endif
90
91static int nsfbufs;
92static int nsfbufspeak;
93static int nsfbufsused;
94
95SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufs, CTLFLAG_RDTUN, &nsfbufs, 0,
96    "Maximum number of sendfile(2) sf_bufs available");
97SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufspeak, CTLFLAG_RD, &nsfbufspeak, 0,
98    "Number of sendfile(2) sf_bufs at peak usage");
99SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufsused, CTLFLAG_RD, &nsfbufsused, 0,
100    "Number of sendfile(2) sf_bufs in use");
101
102static void     sf_buf_init(void *arg);
103SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL);
104
105LIST_HEAD(sf_head, sf_buf);
106
107/*
108 * A hash table of active sendfile(2) buffers
109 */
110static struct sf_head *sf_buf_active;
111static u_long sf_buf_hashmask;
112
113#define SF_BUF_HASH(m)  (((m) - vm_page_array) & sf_buf_hashmask)
114
115static TAILQ_HEAD(, sf_buf) sf_buf_freelist;
116static u_int    sf_buf_alloc_want;
117
118/*
119 * A lock used to synchronize access to the hash table and free list
120 */
121static struct mtx sf_buf_lock;
122#endif /* !ARM_USE_SMALL_ALLOC */
123
124/*
125 * Finish a fork operation, with process p2 nearly set up.
126 * Copy and update the pcb, set up the stack so that the child
127 * ready to run and return to user mode.
128 */
129void
130cpu_fork(register struct thread *td1, register struct proc *p2,
131    struct thread *td2, int flags)
132{
133	struct pcb *pcb2;
134	struct trapframe *tf;
135	struct switchframe *sf;
136	struct mdproc *mdp2;
137
138	if ((flags & RFPROC) == 0)
139		return;
140	pcb2 = (struct pcb *)(td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE) - 1;
141#ifdef __XSCALE__
142#ifndef CPU_XSCALE_CORE3
143	pmap_use_minicache(td2->td_kstack, td2->td_kstack_pages * PAGE_SIZE);
144#endif
145#endif
146	td2->td_pcb = pcb2;
147	bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
148	mdp2 = &p2->p_md;
149	bcopy(&td1->td_proc->p_md, mdp2, sizeof(*mdp2));
150	pcb2->un_32.pcb32_und_sp = td2->td_kstack + USPACE_UNDEF_STACK_TOP;
151	pcb2->un_32.pcb32_sp = td2->td_kstack +
152	    USPACE_SVC_STACK_TOP - sizeof(*pcb2);
153	pmap_activate(td2);
154	td2->td_frame = tf = (struct trapframe *)STACKALIGN(
155	    pcb2->un_32.pcb32_sp - sizeof(struct trapframe));
156	*tf = *td1->td_frame;
157	sf = (struct switchframe *)tf - 1;
158	sf->sf_r4 = (u_int)fork_return;
159	sf->sf_r5 = (u_int)td2;
160	sf->sf_pc = (u_int)fork_trampoline;
161	tf->tf_spsr &= ~PSR_C_bit;
162	tf->tf_r0 = 0;
163	tf->tf_r1 = 0;
164	pcb2->un_32.pcb32_sp = (u_int)sf;
165	KASSERT((pcb2->un_32.pcb32_sp & 7) == 0,
166	    ("cpu_fork: Incorrect stack alignment"));
167
168	/* Setup to release spin count in fork_exit(). */
169	td2->td_md.md_spinlock_count = 1;
170	td2->td_md.md_saved_cspr = 0;
171#ifdef ARM_TP_ADDRESS
172	td2->td_md.md_tp = *(register_t *)ARM_TP_ADDRESS;
173#else
174	td2->td_md.md_tp = (register_t) get_tls();
175#endif
176}
177
178void
179cpu_thread_swapin(struct thread *td)
180{
181}
182
183void
184cpu_thread_swapout(struct thread *td)
185{
186}
187
188/*
189 * Detatch mapped page and release resources back to the system.
190 */
191void
192sf_buf_free(struct sf_buf *sf)
193{
194#ifndef ARM_USE_SMALL_ALLOC
195	 mtx_lock(&sf_buf_lock);
196	 sf->ref_count--;
197	 if (sf->ref_count == 0) {
198		 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry);
199		 nsfbufsused--;
200		 pmap_kremove(sf->kva);
201		 sf->m = NULL;
202		 LIST_REMOVE(sf, list_entry);
203		 if (sf_buf_alloc_want > 0)
204			 wakeup(&sf_buf_freelist);
205	 }
206	 mtx_unlock(&sf_buf_lock);
207#endif
208}
209
210#ifndef ARM_USE_SMALL_ALLOC
211/*
212 * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-))
213 */
214static void
215sf_buf_init(void *arg)
216{
217	struct sf_buf *sf_bufs;
218	vm_offset_t sf_base;
219	int i;
220
221	nsfbufs = NSFBUFS;
222	TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs);
223
224	sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask);
225	TAILQ_INIT(&sf_buf_freelist);
226	sf_base = kva_alloc(nsfbufs * PAGE_SIZE);
227	sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP,
228	    M_NOWAIT | M_ZERO);
229	for (i = 0; i < nsfbufs; i++) {
230		sf_bufs[i].kva = sf_base + i * PAGE_SIZE;
231		TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry);
232	}
233	sf_buf_alloc_want = 0;
234	mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF);
235}
236#endif
237
238/*
239 * Get an sf_buf from the freelist. Will block if none are available.
240 */
241struct sf_buf *
242sf_buf_alloc(struct vm_page *m, int flags)
243{
244#ifdef ARM_USE_SMALL_ALLOC
245	return ((struct sf_buf *)m);
246#else
247	struct sf_head *hash_list;
248	struct sf_buf *sf;
249	int error;
250
251	hash_list = &sf_buf_active[SF_BUF_HASH(m)];
252	mtx_lock(&sf_buf_lock);
253	LIST_FOREACH(sf, hash_list, list_entry) {
254		if (sf->m == m) {
255			sf->ref_count++;
256			if (sf->ref_count == 1) {
257				TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
258				nsfbufsused++;
259				nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
260			}
261			goto done;
262		}
263	}
264	while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) {
265		if (flags & SFB_NOWAIT)
266			goto done;
267		sf_buf_alloc_want++;
268		SFSTAT_INC(sf_allocwait);
269		error = msleep(&sf_buf_freelist, &sf_buf_lock,
270		    (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0);
271		sf_buf_alloc_want--;
272
273
274		/*
275		 * If we got a signal, don't risk going back to sleep.
276		 */
277		if (error)
278			goto done;
279	}
280	TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
281	if (sf->m != NULL)
282		LIST_REMOVE(sf, list_entry);
283	LIST_INSERT_HEAD(hash_list, sf, list_entry);
284	sf->ref_count = 1;
285	sf->m = m;
286	nsfbufsused++;
287	nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
288	pmap_kenter(sf->kva, VM_PAGE_TO_PHYS(sf->m));
289done:
290	mtx_unlock(&sf_buf_lock);
291	return (sf);
292#endif
293}
294
295void
296cpu_set_syscall_retval(struct thread *td, int error)
297{
298	struct trapframe *frame;
299	int fixup;
300#ifdef __ARMEB__
301	uint32_t insn;
302#endif
303
304	frame = td->td_frame;
305	fixup = 0;
306
307#ifdef __ARMEB__
308	insn = *(u_int32_t *)(frame->tf_pc - INSN_SIZE);
309	if ((insn & 0x000fffff) == SYS___syscall) {
310		register_t *ap = &frame->tf_r0;
311		register_t code = ap[_QUAD_LOWWORD];
312		if (td->td_proc->p_sysent->sv_mask)
313			code &= td->td_proc->p_sysent->sv_mask;
314		fixup = (code != SYS_freebsd6_lseek && code != SYS_lseek)
315		    ? 1 : 0;
316	}
317#endif
318
319	switch (error) {
320	case 0:
321		if (fixup) {
322			frame->tf_r0 = 0;
323			frame->tf_r1 = td->td_retval[0];
324		} else {
325			frame->tf_r0 = td->td_retval[0];
326			frame->tf_r1 = td->td_retval[1];
327		}
328		frame->tf_spsr &= ~PSR_C_bit;   /* carry bit */
329		break;
330	case ERESTART:
331		/*
332		 * Reconstruct the pc to point at the swi.
333		 */
334		frame->tf_pc -= INSN_SIZE;
335		break;
336	case EJUSTRETURN:
337		/* nothing to do */
338		break;
339	default:
340		frame->tf_r0 = error;
341		frame->tf_spsr |= PSR_C_bit;    /* carry bit */
342		break;
343	}
344}
345
346/*
347 * Initialize machine state (pcb and trap frame) for a new thread about to
348 * upcall. Put enough state in the new thread's PCB to get it to go back
349 * userret(), where we can intercept it again to set the return (upcall)
350 * Address and stack, along with those from upcals that are from other sources
351 * such as those generated in thread_userret() itself.
352 */
353void
354cpu_set_upcall(struct thread *td, struct thread *td0)
355{
356	struct trapframe *tf;
357	struct switchframe *sf;
358
359	bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe));
360	bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb));
361	tf = td->td_frame;
362	sf = (struct switchframe *)tf - 1;
363	sf->sf_r4 = (u_int)fork_return;
364	sf->sf_r5 = (u_int)td;
365	sf->sf_pc = (u_int)fork_trampoline;
366	tf->tf_spsr &= ~PSR_C_bit;
367	tf->tf_r0 = 0;
368	td->td_pcb->un_32.pcb32_sp = (u_int)sf;
369	td->td_pcb->un_32.pcb32_und_sp = td->td_kstack + USPACE_UNDEF_STACK_TOP;
370	KASSERT((td->td_pcb->un_32.pcb32_sp & 7) == 0,
371	    ("cpu_set_upcall: Incorrect stack alignment"));
372
373	/* Setup to release spin count in fork_exit(). */
374	td->td_md.md_spinlock_count = 1;
375	td->td_md.md_saved_cspr = 0;
376}
377
378/*
379 * Set that machine state for performing an upcall that has to
380 * be done in thread_userret() so that those upcalls generated
381 * in thread_userret() itself can be done as well.
382 */
383void
384cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg,
385	stack_t *stack)
386{
387	struct trapframe *tf = td->td_frame;
388
389	tf->tf_usr_sp = STACKALIGN((int)stack->ss_sp + stack->ss_size
390	    - sizeof(struct trapframe));
391	tf->tf_pc = (int)entry;
392	tf->tf_r0 = (int)arg;
393	tf->tf_spsr = PSR_USR32_MODE;
394}
395
396int
397cpu_set_user_tls(struct thread *td, void *tls_base)
398{
399
400	td->td_md.md_tp = (register_t)tls_base;
401	if (td == curthread) {
402		critical_enter();
403#ifdef ARM_TP_ADDRESS
404		*(register_t *)ARM_TP_ADDRESS = (register_t)tls_base;
405#else
406		set_tls((void *)tls_base);
407#endif
408		critical_exit();
409	}
410	return (0);
411}
412
413void
414cpu_thread_exit(struct thread *td)
415{
416}
417
418void
419cpu_thread_alloc(struct thread *td)
420{
421	td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages *
422	    PAGE_SIZE) - 1;
423	/*
424	 * Ensure td_frame is aligned to an 8 byte boundary as it will be
425	 * placed into the stack pointer which must be 8 byte aligned in
426	 * the ARM EABI.
427	 */
428	td->td_frame = (struct trapframe *)STACKALIGN((u_int)td->td_kstack +
429	    USPACE_SVC_STACK_TOP - sizeof(struct pcb) -
430	    sizeof(struct trapframe));
431#ifdef __XSCALE__
432#ifndef CPU_XSCALE_CORE3
433	pmap_use_minicache(td->td_kstack, td->td_kstack_pages * PAGE_SIZE);
434#endif
435#endif
436}
437
438void
439cpu_thread_free(struct thread *td)
440{
441}
442
443void
444cpu_thread_clean(struct thread *td)
445{
446}
447
448/*
449 * Intercept the return address from a freshly forked process that has NOT
450 * been scheduled yet.
451 *
452 * This is needed to make kernel threads stay in kernel mode.
453 */
454void
455cpu_set_fork_handler(struct thread *td, void (*func)(void *), void *arg)
456{
457	struct switchframe *sf;
458	struct trapframe *tf;
459
460	tf = td->td_frame;
461	sf = (struct switchframe *)tf - 1;
462	sf->sf_r4 = (u_int)func;
463	sf->sf_r5 = (u_int)arg;
464	td->td_pcb->un_32.pcb32_sp = (u_int)sf;
465	KASSERT((td->td_pcb->un_32.pcb32_sp & 7) == 0,
466	    ("cpu_set_fork_handler: Incorrect stack alignment"));
467}
468
469/*
470 * Software interrupt handler for queued VM system processing.
471 */
472void
473swi_vm(void *dummy)
474{
475
476	if (busdma_swi_pending)
477		busdma_swi();
478}
479
480void
481cpu_exit(struct thread *td)
482{
483}
484
485#ifdef ARM_USE_SMALL_ALLOC
486
487static TAILQ_HEAD(,arm_small_page) pages_normal =
488	TAILQ_HEAD_INITIALIZER(pages_normal);
489static TAILQ_HEAD(,arm_small_page) pages_wt =
490	TAILQ_HEAD_INITIALIZER(pages_wt);
491static TAILQ_HEAD(,arm_small_page) free_pgdesc =
492	TAILQ_HEAD_INITIALIZER(free_pgdesc);
493
494extern uma_zone_t l2zone;
495
496struct mtx smallalloc_mtx;
497
498vm_offset_t alloc_firstaddr;
499
500#ifdef ARM_HAVE_SUPERSECTIONS
501#define S_FRAME	L1_SUP_FRAME
502#define S_SIZE	L1_SUP_SIZE
503#else
504#define S_FRAME	L1_S_FRAME
505#define S_SIZE	L1_S_SIZE
506#endif
507
508vm_offset_t
509arm_ptovirt(vm_paddr_t pa)
510{
511	int i;
512	vm_offset_t addr = alloc_firstaddr;
513
514	KASSERT(alloc_firstaddr != 0, ("arm_ptovirt called too early ?"));
515	for (i = 0; dump_avail[i + 1]; i += 2) {
516		if (pa >= dump_avail[i] && pa < dump_avail[i + 1])
517			break;
518		addr += (dump_avail[i + 1] & S_FRAME) + S_SIZE -
519		    (dump_avail[i] & S_FRAME);
520	}
521	KASSERT(dump_avail[i + 1] != 0, ("Trying to access invalid physical address"));
522	return (addr + (pa - (dump_avail[i] & S_FRAME)));
523}
524
525void
526arm_init_smallalloc(void)
527{
528	vm_offset_t to_map = 0, mapaddr;
529	int i;
530
531	/*
532	 * We need to use dump_avail and not phys_avail, since we want to
533	 * map the whole memory and not just the memory available to the VM
534	 * to be able to do a pa => va association for any address.
535	 */
536
537	for (i = 0; dump_avail[i + 1]; i+= 2) {
538		to_map += (dump_avail[i + 1] & S_FRAME) + S_SIZE -
539		    (dump_avail[i] & S_FRAME);
540	}
541	alloc_firstaddr = mapaddr = KERNBASE - to_map;
542	for (i = 0; dump_avail[i + 1]; i+= 2) {
543		vm_offset_t size = (dump_avail[i + 1] & S_FRAME) +
544		    S_SIZE - (dump_avail[i] & S_FRAME);
545		vm_offset_t did = 0;
546		while (size > 0) {
547#ifdef ARM_HAVE_SUPERSECTIONS
548			pmap_kenter_supersection(mapaddr,
549			    (dump_avail[i] & L1_SUP_FRAME) + did,
550			    SECTION_CACHE);
551#else
552			pmap_kenter_section(mapaddr,
553			    (dump_avail[i] & L1_S_FRAME) + did, SECTION_CACHE);
554#endif
555			mapaddr += S_SIZE;
556			did += S_SIZE;
557			size -= S_SIZE;
558		}
559	}
560}
561
562void
563arm_add_smallalloc_pages(void *list, void *mem, int bytes, int pagetable)
564{
565	struct arm_small_page *pg;
566
567	bytes &= ~PAGE_MASK;
568	while (bytes > 0) {
569		pg = (struct arm_small_page *)list;
570		pg->addr = mem;
571		if (pagetable)
572			TAILQ_INSERT_HEAD(&pages_wt, pg, pg_list);
573		else
574			TAILQ_INSERT_HEAD(&pages_normal, pg, pg_list);
575		list = (char *)list + sizeof(*pg);
576		mem = (char *)mem + PAGE_SIZE;
577		bytes -= PAGE_SIZE;
578	}
579}
580
581void *
582uma_small_alloc(uma_zone_t zone, int bytes, u_int8_t *flags, int wait)
583{
584	void *ret;
585	struct arm_small_page *sp;
586	TAILQ_HEAD(,arm_small_page) *head;
587	vm_page_t m;
588
589	*flags = UMA_SLAB_PRIV;
590	/*
591	 * For CPUs where we setup page tables as write back, there's no
592	 * need to maintain two separate pools.
593	 */
594	if (zone == l2zone && pte_l1_s_cache_mode != pte_l1_s_cache_mode_pt)
595		head = (void *)&pages_wt;
596	else
597		head = (void *)&pages_normal;
598
599	mtx_lock(&smallalloc_mtx);
600	sp = TAILQ_FIRST(head);
601
602	if (!sp) {
603		int pflags;
604
605		mtx_unlock(&smallalloc_mtx);
606		if (zone == l2zone &&
607		    pte_l1_s_cache_mode != pte_l1_s_cache_mode_pt) {
608			*flags = UMA_SLAB_KMEM;
609			ret = ((void *)kmem_malloc(kmem_arena, bytes,
610			    M_NOWAIT));
611			return (ret);
612		}
613		pflags = malloc2vm_flags(wait) | VM_ALLOC_WIRED;
614		for (;;) {
615			m = vm_page_alloc(NULL, 0, pflags | VM_ALLOC_NOOBJ);
616			if (m == NULL) {
617				if (wait & M_NOWAIT)
618					return (NULL);
619				VM_WAIT;
620			} else
621				break;
622		}
623		ret = (void *)arm_ptovirt(VM_PAGE_TO_PHYS(m));
624		if ((wait & M_ZERO) && (m->flags & PG_ZERO) == 0)
625			bzero(ret, PAGE_SIZE);
626		return (ret);
627	}
628	TAILQ_REMOVE(head, sp, pg_list);
629	TAILQ_INSERT_HEAD(&free_pgdesc, sp, pg_list);
630	ret = sp->addr;
631	mtx_unlock(&smallalloc_mtx);
632	if ((wait & M_ZERO))
633		bzero(ret, bytes);
634	return (ret);
635}
636
637void
638uma_small_free(void *mem, int size, u_int8_t flags)
639{
640	pd_entry_t *pd;
641	pt_entry_t *pt;
642
643	if (flags & UMA_SLAB_KMEM)
644		kmem_free(kmem_arena, (vm_offset_t)mem, size);
645	else {
646		struct arm_small_page *sp;
647
648		if ((vm_offset_t)mem >= KERNBASE) {
649			mtx_lock(&smallalloc_mtx);
650			sp = TAILQ_FIRST(&free_pgdesc);
651			KASSERT(sp != NULL, ("No more free page descriptor ?"));
652			TAILQ_REMOVE(&free_pgdesc, sp, pg_list);
653			sp->addr = mem;
654			pmap_get_pde_pte(kernel_pmap, (vm_offset_t)mem, &pd,
655			    &pt);
656			if ((*pd & pte_l1_s_cache_mask) ==
657			    pte_l1_s_cache_mode_pt &&
658			    pte_l1_s_cache_mode_pt != pte_l1_s_cache_mode)
659				TAILQ_INSERT_HEAD(&pages_wt, sp, pg_list);
660			else
661				TAILQ_INSERT_HEAD(&pages_normal, sp, pg_list);
662			mtx_unlock(&smallalloc_mtx);
663		} else {
664			vm_page_t m;
665			vm_paddr_t pa = vtophys((vm_offset_t)mem);
666
667			m = PHYS_TO_VM_PAGE(pa);
668			m->wire_count--;
669			vm_page_free(m);
670			atomic_subtract_int(&cnt.v_wire_count, 1);
671		}
672	}
673}
674
675#endif
676