vm_machdep.c revision 266160
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 266160 2014-05-15 17:30:16Z 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	u_int call;
302#endif
303
304	frame = td->td_frame;
305	fixup = 0;
306
307#ifdef __ARMEB__
308	/*
309	 * __syscall returns an off_t while most other syscalls return an
310	 * int. As an off_t is 64-bits and an int is 32-bits we need to
311	 * place the returned data into r1. As the lseek and frerebsd6_lseek
312	 * syscalls also return an off_t they do not need this fixup.
313	 */
314#ifdef __ARM_EABI__
315	call = frame->tf_r7;
316#else
317	call = *(u_int32_t *)(frame->tf_pc - INSN_SIZE) & 0x000fffff;
318#endif
319	if (call == SYS___syscall) {
320		register_t *ap = &frame->tf_r0;
321		register_t code = ap[_QUAD_LOWWORD];
322		if (td->td_proc->p_sysent->sv_mask)
323			code &= td->td_proc->p_sysent->sv_mask;
324		fixup = (code != SYS_freebsd6_lseek && code != SYS_lseek)
325		    ? 1 : 0;
326	}
327#endif
328
329	switch (error) {
330	case 0:
331		if (fixup) {
332			frame->tf_r0 = 0;
333			frame->tf_r1 = td->td_retval[0];
334		} else {
335			frame->tf_r0 = td->td_retval[0];
336			frame->tf_r1 = td->td_retval[1];
337		}
338		frame->tf_spsr &= ~PSR_C_bit;   /* carry bit */
339		break;
340	case ERESTART:
341		/*
342		 * Reconstruct the pc to point at the swi.
343		 */
344		frame->tf_pc -= INSN_SIZE;
345		break;
346	case EJUSTRETURN:
347		/* nothing to do */
348		break;
349	default:
350		frame->tf_r0 = error;
351		frame->tf_spsr |= PSR_C_bit;    /* carry bit */
352		break;
353	}
354}
355
356/*
357 * Initialize machine state (pcb and trap frame) for a new thread about to
358 * upcall. Put enough state in the new thread's PCB to get it to go back
359 * userret(), where we can intercept it again to set the return (upcall)
360 * Address and stack, along with those from upcals that are from other sources
361 * such as those generated in thread_userret() itself.
362 */
363void
364cpu_set_upcall(struct thread *td, struct thread *td0)
365{
366	struct trapframe *tf;
367	struct switchframe *sf;
368
369	bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe));
370	bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb));
371	tf = td->td_frame;
372	sf = (struct switchframe *)tf - 1;
373	sf->sf_r4 = (u_int)fork_return;
374	sf->sf_r5 = (u_int)td;
375	sf->sf_pc = (u_int)fork_trampoline;
376	tf->tf_spsr &= ~PSR_C_bit;
377	tf->tf_r0 = 0;
378	td->td_pcb->un_32.pcb32_sp = (u_int)sf;
379	td->td_pcb->un_32.pcb32_und_sp = td->td_kstack + USPACE_UNDEF_STACK_TOP;
380	KASSERT((td->td_pcb->un_32.pcb32_sp & 7) == 0,
381	    ("cpu_set_upcall: Incorrect stack alignment"));
382
383	/* Setup to release spin count in fork_exit(). */
384	td->td_md.md_spinlock_count = 1;
385	td->td_md.md_saved_cspr = 0;
386}
387
388/*
389 * Set that machine state for performing an upcall that has to
390 * be done in thread_userret() so that those upcalls generated
391 * in thread_userret() itself can be done as well.
392 */
393void
394cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg,
395	stack_t *stack)
396{
397	struct trapframe *tf = td->td_frame;
398
399	tf->tf_usr_sp = STACKALIGN((int)stack->ss_sp + stack->ss_size
400	    - sizeof(struct trapframe));
401	tf->tf_pc = (int)entry;
402	tf->tf_r0 = (int)arg;
403	tf->tf_spsr = PSR_USR32_MODE;
404}
405
406int
407cpu_set_user_tls(struct thread *td, void *tls_base)
408{
409
410	td->td_md.md_tp = (register_t)tls_base;
411	if (td == curthread) {
412		critical_enter();
413#ifdef ARM_TP_ADDRESS
414		*(register_t *)ARM_TP_ADDRESS = (register_t)tls_base;
415#else
416		set_tls((void *)tls_base);
417#endif
418		critical_exit();
419	}
420	return (0);
421}
422
423void
424cpu_thread_exit(struct thread *td)
425{
426}
427
428void
429cpu_thread_alloc(struct thread *td)
430{
431	td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages *
432	    PAGE_SIZE) - 1;
433	/*
434	 * Ensure td_frame is aligned to an 8 byte boundary as it will be
435	 * placed into the stack pointer which must be 8 byte aligned in
436	 * the ARM EABI.
437	 */
438	td->td_frame = (struct trapframe *)STACKALIGN((u_int)td->td_kstack +
439	    USPACE_SVC_STACK_TOP - sizeof(struct pcb) -
440	    sizeof(struct trapframe));
441#ifdef __XSCALE__
442#ifndef CPU_XSCALE_CORE3
443	pmap_use_minicache(td->td_kstack, td->td_kstack_pages * PAGE_SIZE);
444#endif
445#endif
446}
447
448void
449cpu_thread_free(struct thread *td)
450{
451}
452
453void
454cpu_thread_clean(struct thread *td)
455{
456}
457
458/*
459 * Intercept the return address from a freshly forked process that has NOT
460 * been scheduled yet.
461 *
462 * This is needed to make kernel threads stay in kernel mode.
463 */
464void
465cpu_set_fork_handler(struct thread *td, void (*func)(void *), void *arg)
466{
467	struct switchframe *sf;
468	struct trapframe *tf;
469
470	tf = td->td_frame;
471	sf = (struct switchframe *)tf - 1;
472	sf->sf_r4 = (u_int)func;
473	sf->sf_r5 = (u_int)arg;
474	td->td_pcb->un_32.pcb32_sp = (u_int)sf;
475	KASSERT((td->td_pcb->un_32.pcb32_sp & 7) == 0,
476	    ("cpu_set_fork_handler: Incorrect stack alignment"));
477}
478
479/*
480 * Software interrupt handler for queued VM system processing.
481 */
482void
483swi_vm(void *dummy)
484{
485
486	if (busdma_swi_pending)
487		busdma_swi();
488}
489
490void
491cpu_exit(struct thread *td)
492{
493}
494
495#ifdef ARM_USE_SMALL_ALLOC
496
497static TAILQ_HEAD(,arm_small_page) pages_normal =
498	TAILQ_HEAD_INITIALIZER(pages_normal);
499static TAILQ_HEAD(,arm_small_page) pages_wt =
500	TAILQ_HEAD_INITIALIZER(pages_wt);
501static TAILQ_HEAD(,arm_small_page) free_pgdesc =
502	TAILQ_HEAD_INITIALIZER(free_pgdesc);
503
504extern uma_zone_t l2zone;
505
506struct mtx smallalloc_mtx;
507
508vm_offset_t alloc_firstaddr;
509
510#ifdef ARM_HAVE_SUPERSECTIONS
511#define S_FRAME	L1_SUP_FRAME
512#define S_SIZE	L1_SUP_SIZE
513#else
514#define S_FRAME	L1_S_FRAME
515#define S_SIZE	L1_S_SIZE
516#endif
517
518vm_offset_t
519arm_ptovirt(vm_paddr_t pa)
520{
521	int i;
522	vm_offset_t addr = alloc_firstaddr;
523
524	KASSERT(alloc_firstaddr != 0, ("arm_ptovirt called too early ?"));
525	for (i = 0; dump_avail[i + 1]; i += 2) {
526		if (pa >= dump_avail[i] && pa < dump_avail[i + 1])
527			break;
528		addr += (dump_avail[i + 1] & S_FRAME) + S_SIZE -
529		    (dump_avail[i] & S_FRAME);
530	}
531	KASSERT(dump_avail[i + 1] != 0, ("Trying to access invalid physical address"));
532	return (addr + (pa - (dump_avail[i] & S_FRAME)));
533}
534
535void
536arm_init_smallalloc(void)
537{
538	vm_offset_t to_map = 0, mapaddr;
539	int i;
540
541	/*
542	 * We need to use dump_avail and not phys_avail, since we want to
543	 * map the whole memory and not just the memory available to the VM
544	 * to be able to do a pa => va association for any address.
545	 */
546
547	for (i = 0; dump_avail[i + 1]; i+= 2) {
548		to_map += (dump_avail[i + 1] & S_FRAME) + S_SIZE -
549		    (dump_avail[i] & S_FRAME);
550	}
551	alloc_firstaddr = mapaddr = KERNBASE - to_map;
552	for (i = 0; dump_avail[i + 1]; i+= 2) {
553		vm_offset_t size = (dump_avail[i + 1] & S_FRAME) +
554		    S_SIZE - (dump_avail[i] & S_FRAME);
555		vm_offset_t did = 0;
556		while (size > 0) {
557#ifdef ARM_HAVE_SUPERSECTIONS
558			pmap_kenter_supersection(mapaddr,
559			    (dump_avail[i] & L1_SUP_FRAME) + did,
560			    SECTION_CACHE);
561#else
562			pmap_kenter_section(mapaddr,
563			    (dump_avail[i] & L1_S_FRAME) + did, SECTION_CACHE);
564#endif
565			mapaddr += S_SIZE;
566			did += S_SIZE;
567			size -= S_SIZE;
568		}
569	}
570}
571
572void
573arm_add_smallalloc_pages(void *list, void *mem, int bytes, int pagetable)
574{
575	struct arm_small_page *pg;
576
577	bytes &= ~PAGE_MASK;
578	while (bytes > 0) {
579		pg = (struct arm_small_page *)list;
580		pg->addr = mem;
581		if (pagetable)
582			TAILQ_INSERT_HEAD(&pages_wt, pg, pg_list);
583		else
584			TAILQ_INSERT_HEAD(&pages_normal, pg, pg_list);
585		list = (char *)list + sizeof(*pg);
586		mem = (char *)mem + PAGE_SIZE;
587		bytes -= PAGE_SIZE;
588	}
589}
590
591void *
592uma_small_alloc(uma_zone_t zone, int bytes, u_int8_t *flags, int wait)
593{
594	void *ret;
595	struct arm_small_page *sp;
596	TAILQ_HEAD(,arm_small_page) *head;
597	vm_page_t m;
598
599	*flags = UMA_SLAB_PRIV;
600	/*
601	 * For CPUs where we setup page tables as write back, there's no
602	 * need to maintain two separate pools.
603	 */
604	if (zone == l2zone && pte_l1_s_cache_mode != pte_l1_s_cache_mode_pt)
605		head = (void *)&pages_wt;
606	else
607		head = (void *)&pages_normal;
608
609	mtx_lock(&smallalloc_mtx);
610	sp = TAILQ_FIRST(head);
611
612	if (!sp) {
613		int pflags;
614
615		mtx_unlock(&smallalloc_mtx);
616		if (zone == l2zone &&
617		    pte_l1_s_cache_mode != pte_l1_s_cache_mode_pt) {
618			*flags = UMA_SLAB_KMEM;
619			ret = ((void *)kmem_malloc(kmem_arena, bytes,
620			    M_NOWAIT));
621			return (ret);
622		}
623		pflags = malloc2vm_flags(wait) | VM_ALLOC_WIRED;
624		for (;;) {
625			m = vm_page_alloc(NULL, 0, pflags | VM_ALLOC_NOOBJ);
626			if (m == NULL) {
627				if (wait & M_NOWAIT)
628					return (NULL);
629				VM_WAIT;
630			} else
631				break;
632		}
633		ret = (void *)arm_ptovirt(VM_PAGE_TO_PHYS(m));
634		if ((wait & M_ZERO) && (m->flags & PG_ZERO) == 0)
635			bzero(ret, PAGE_SIZE);
636		return (ret);
637	}
638	TAILQ_REMOVE(head, sp, pg_list);
639	TAILQ_INSERT_HEAD(&free_pgdesc, sp, pg_list);
640	ret = sp->addr;
641	mtx_unlock(&smallalloc_mtx);
642	if ((wait & M_ZERO))
643		bzero(ret, bytes);
644	return (ret);
645}
646
647void
648uma_small_free(void *mem, int size, u_int8_t flags)
649{
650	pd_entry_t *pd;
651	pt_entry_t *pt;
652
653	if (flags & UMA_SLAB_KMEM)
654		kmem_free(kmem_arena, (vm_offset_t)mem, size);
655	else {
656		struct arm_small_page *sp;
657
658		if ((vm_offset_t)mem >= KERNBASE) {
659			mtx_lock(&smallalloc_mtx);
660			sp = TAILQ_FIRST(&free_pgdesc);
661			KASSERT(sp != NULL, ("No more free page descriptor ?"));
662			TAILQ_REMOVE(&free_pgdesc, sp, pg_list);
663			sp->addr = mem;
664			pmap_get_pde_pte(kernel_pmap, (vm_offset_t)mem, &pd,
665			    &pt);
666			if ((*pd & pte_l1_s_cache_mask) ==
667			    pte_l1_s_cache_mode_pt &&
668			    pte_l1_s_cache_mode_pt != pte_l1_s_cache_mode)
669				TAILQ_INSERT_HEAD(&pages_wt, sp, pg_list);
670			else
671				TAILQ_INSERT_HEAD(&pages_normal, sp, pg_list);
672			mtx_unlock(&smallalloc_mtx);
673		} else {
674			vm_page_t m;
675			vm_paddr_t pa = vtophys((vm_offset_t)mem);
676
677			m = PHYS_TO_VM_PAGE(pa);
678			m->wire_count--;
679			vm_page_free(m);
680			atomic_subtract_int(&cnt.v_wire_count, 1);
681		}
682	}
683}
684
685#endif
686