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9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/types.h>
12#include <linux/string.h>
13#include <linux/kernel.h>
14#include <linux/pagemap.h>
15#include <linux/errno.h>
16#include <linux/sunrpc/xdr.h>
17#include <linux/sunrpc/msg_prot.h>
18
19
20
21
22__be32 *
23xdr_encode_netobj(__be32 *p, const struct xdr_netobj *obj)
24{
25 unsigned int quadlen = XDR_QUADLEN(obj->len);
26
27 p[quadlen] = 0;
28 *p++ = cpu_to_be32(obj->len);
29 memcpy(p, obj->data, obj->len);
30 return p + XDR_QUADLEN(obj->len);
31}
32EXPORT_SYMBOL_GPL(xdr_encode_netobj);
33
34__be32 *
35xdr_decode_netobj(__be32 *p, struct xdr_netobj *obj)
36{
37 unsigned int len;
38
39 if ((len = be32_to_cpu(*p++)) > XDR_MAX_NETOBJ)
40 return NULL;
41 obj->len = len;
42 obj->data = (u8 *) p;
43 return p + XDR_QUADLEN(len);
44}
45EXPORT_SYMBOL_GPL(xdr_decode_netobj);
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60
61__be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int nbytes)
62{
63 if (likely(nbytes != 0)) {
64 unsigned int quadlen = XDR_QUADLEN(nbytes);
65 unsigned int padding = (quadlen << 2) - nbytes;
66
67 if (ptr != NULL)
68 memcpy(p, ptr, nbytes);
69 if (padding != 0)
70 memset((char *)p + nbytes, 0, padding);
71 p += quadlen;
72 }
73 return p;
74}
75EXPORT_SYMBOL_GPL(xdr_encode_opaque_fixed);
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83
84
85__be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int nbytes)
86{
87 *p++ = cpu_to_be32(nbytes);
88 return xdr_encode_opaque_fixed(p, ptr, nbytes);
89}
90EXPORT_SYMBOL_GPL(xdr_encode_opaque);
91
92__be32 *
93xdr_encode_string(__be32 *p, const char *string)
94{
95 return xdr_encode_array(p, string, strlen(string));
96}
97EXPORT_SYMBOL_GPL(xdr_encode_string);
98
99__be32 *
100xdr_decode_string_inplace(__be32 *p, char **sp,
101 unsigned int *lenp, unsigned int maxlen)
102{
103 u32 len;
104
105 len = be32_to_cpu(*p++);
106 if (len > maxlen)
107 return NULL;
108 *lenp = len;
109 *sp = (char *) p;
110 return p + XDR_QUADLEN(len);
111}
112EXPORT_SYMBOL_GPL(xdr_decode_string_inplace);
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118
119
120void
121xdr_terminate_string(struct xdr_buf *buf, const u32 len)
122{
123 char *kaddr;
124
125 kaddr = kmap_atomic(buf->pages[0]);
126 kaddr[buf->page_base + len] = '\0';
127 kunmap_atomic(kaddr);
128}
129EXPORT_SYMBOL_GPL(xdr_terminate_string);
130
131void
132xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset,
133 struct page **pages, unsigned int base, unsigned int len)
134{
135 struct kvec *head = xdr->head;
136 struct kvec *tail = xdr->tail;
137 char *buf = (char *)head->iov_base;
138 unsigned int buflen = head->iov_len;
139
140 head->iov_len = offset;
141
142 xdr->pages = pages;
143 xdr->page_base = base;
144 xdr->page_len = len;
145
146 tail->iov_base = buf + offset;
147 tail->iov_len = buflen - offset;
148
149 xdr->buflen += len;
150}
151EXPORT_SYMBOL_GPL(xdr_inline_pages);
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170
171static void
172_shift_data_right_pages(struct page **pages, size_t pgto_base,
173 size_t pgfrom_base, size_t len)
174{
175 struct page **pgfrom, **pgto;
176 char *vfrom, *vto;
177 size_t copy;
178
179 BUG_ON(pgto_base <= pgfrom_base);
180
181 pgto_base += len;
182 pgfrom_base += len;
183
184 pgto = pages + (pgto_base >> PAGE_CACHE_SHIFT);
185 pgfrom = pages + (pgfrom_base >> PAGE_CACHE_SHIFT);
186
187 pgto_base &= ~PAGE_CACHE_MASK;
188 pgfrom_base &= ~PAGE_CACHE_MASK;
189
190 do {
191
192 if (pgto_base == 0) {
193 pgto_base = PAGE_CACHE_SIZE;
194 pgto--;
195 }
196 if (pgfrom_base == 0) {
197 pgfrom_base = PAGE_CACHE_SIZE;
198 pgfrom--;
199 }
200
201 copy = len;
202 if (copy > pgto_base)
203 copy = pgto_base;
204 if (copy > pgfrom_base)
205 copy = pgfrom_base;
206 pgto_base -= copy;
207 pgfrom_base -= copy;
208
209 vto = kmap_atomic(*pgto);
210 if (*pgto != *pgfrom) {
211 vfrom = kmap_atomic(*pgfrom);
212 memcpy(vto + pgto_base, vfrom + pgfrom_base, copy);
213 kunmap_atomic(vfrom);
214 } else
215 memmove(vto + pgto_base, vto + pgfrom_base, copy);
216 flush_dcache_page(*pgto);
217 kunmap_atomic(vto);
218
219 } while ((len -= copy) != 0);
220}
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231
232static void
233_copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
234{
235 struct page **pgto;
236 char *vto;
237 size_t copy;
238
239 pgto = pages + (pgbase >> PAGE_CACHE_SHIFT);
240 pgbase &= ~PAGE_CACHE_MASK;
241
242 for (;;) {
243 copy = PAGE_CACHE_SIZE - pgbase;
244 if (copy > len)
245 copy = len;
246
247 vto = kmap_atomic(*pgto);
248 memcpy(vto + pgbase, p, copy);
249 kunmap_atomic(vto);
250
251 len -= copy;
252 if (len == 0)
253 break;
254
255 pgbase += copy;
256 if (pgbase == PAGE_CACHE_SIZE) {
257 flush_dcache_page(*pgto);
258 pgbase = 0;
259 pgto++;
260 }
261 p += copy;
262 }
263 flush_dcache_page(*pgto);
264}
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275
276void
277_copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
278{
279 struct page **pgfrom;
280 char *vfrom;
281 size_t copy;
282
283 pgfrom = pages + (pgbase >> PAGE_CACHE_SHIFT);
284 pgbase &= ~PAGE_CACHE_MASK;
285
286 do {
287 copy = PAGE_CACHE_SIZE - pgbase;
288 if (copy > len)
289 copy = len;
290
291 vfrom = kmap_atomic(*pgfrom);
292 memcpy(p, vfrom + pgbase, copy);
293 kunmap_atomic(vfrom);
294
295 pgbase += copy;
296 if (pgbase == PAGE_CACHE_SIZE) {
297 pgbase = 0;
298 pgfrom++;
299 }
300 p += copy;
301
302 } while ((len -= copy) != 0);
303}
304EXPORT_SYMBOL_GPL(_copy_from_pages);
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314
315static void
316xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
317{
318 struct kvec *head, *tail;
319 size_t copy, offs;
320 unsigned int pglen = buf->page_len;
321
322 tail = buf->tail;
323 head = buf->head;
324
325 WARN_ON_ONCE(len > head->iov_len);
326 if (len > head->iov_len)
327 len = head->iov_len;
328
329
330 if (tail->iov_len != 0) {
331 if (tail->iov_len > len) {
332 copy = tail->iov_len - len;
333 memmove((char *)tail->iov_base + len,
334 tail->iov_base, copy);
335 }
336
337 copy = len;
338 if (copy > pglen)
339 copy = pglen;
340 offs = len - copy;
341 if (offs >= tail->iov_len)
342 copy = 0;
343 else if (copy > tail->iov_len - offs)
344 copy = tail->iov_len - offs;
345 if (copy != 0)
346 _copy_from_pages((char *)tail->iov_base + offs,
347 buf->pages,
348 buf->page_base + pglen + offs - len,
349 copy);
350
351 if (len > pglen) {
352 offs = copy = len - pglen;
353 if (copy > tail->iov_len)
354 copy = tail->iov_len;
355 memcpy(tail->iov_base,
356 (char *)head->iov_base +
357 head->iov_len - offs,
358 copy);
359 }
360 }
361
362 if (pglen != 0) {
363 if (pglen > len)
364 _shift_data_right_pages(buf->pages,
365 buf->page_base + len,
366 buf->page_base,
367 pglen - len);
368 copy = len;
369 if (len > pglen)
370 copy = pglen;
371 _copy_to_pages(buf->pages, buf->page_base,
372 (char *)head->iov_base + head->iov_len - len,
373 copy);
374 }
375 head->iov_len -= len;
376 buf->buflen -= len;
377
378 if (buf->len > buf->buflen)
379 buf->len = buf->buflen;
380}
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390
391static void
392xdr_shrink_pagelen(struct xdr_buf *buf, size_t len)
393{
394 struct kvec *tail;
395 size_t copy;
396 unsigned int pglen = buf->page_len;
397 unsigned int tailbuf_len;
398
399 tail = buf->tail;
400 BUG_ON (len > pglen);
401
402 tailbuf_len = buf->buflen - buf->head->iov_len - buf->page_len;
403
404
405 if (tailbuf_len != 0) {
406 unsigned int free_space = tailbuf_len - tail->iov_len;
407
408 if (len < free_space)
409 free_space = len;
410 tail->iov_len += free_space;
411
412 copy = len;
413 if (tail->iov_len > len) {
414 char *p = (char *)tail->iov_base + len;
415 memmove(p, tail->iov_base, tail->iov_len - len);
416 } else
417 copy = tail->iov_len;
418
419 _copy_from_pages((char *)tail->iov_base,
420 buf->pages, buf->page_base + pglen - len,
421 copy);
422 }
423 buf->page_len -= len;
424 buf->buflen -= len;
425
426 if (buf->len > buf->buflen)
427 buf->len = buf->buflen;
428}
429
430void
431xdr_shift_buf(struct xdr_buf *buf, size_t len)
432{
433 xdr_shrink_bufhead(buf, len);
434}
435EXPORT_SYMBOL_GPL(xdr_shift_buf);
436
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440
441unsigned int xdr_stream_pos(const struct xdr_stream *xdr)
442{
443 return (unsigned int)(XDR_QUADLEN(xdr->buf->len) - xdr->nwords) << 2;
444}
445EXPORT_SYMBOL_GPL(xdr_stream_pos);
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459
460void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
461{
462 struct kvec *iov = buf->head;
463 int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len;
464
465 xdr_set_scratch_buffer(xdr, NULL, 0);
466 BUG_ON(scratch_len < 0);
467 xdr->buf = buf;
468 xdr->iov = iov;
469 xdr->p = (__be32 *)((char *)iov->iov_base + iov->iov_len);
470 xdr->end = (__be32 *)((char *)iov->iov_base + scratch_len);
471 BUG_ON(iov->iov_len > scratch_len);
472
473 if (p != xdr->p && p != NULL) {
474 size_t len;
475
476 BUG_ON(p < xdr->p || p > xdr->end);
477 len = (char *)p - (char *)xdr->p;
478 xdr->p = p;
479 buf->len += len;
480 iov->iov_len += len;
481 }
482}
483EXPORT_SYMBOL_GPL(xdr_init_encode);
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496
497
498void xdr_commit_encode(struct xdr_stream *xdr)
499{
500 int shift = xdr->scratch.iov_len;
501 void *page;
502
503 if (shift == 0)
504 return;
505 page = page_address(*xdr->page_ptr);
506 memcpy(xdr->scratch.iov_base, page, shift);
507 memmove(page, page + shift, (void *)xdr->p - page);
508 xdr->scratch.iov_len = 0;
509}
510EXPORT_SYMBOL_GPL(xdr_commit_encode);
511
512static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr,
513 size_t nbytes)
514{
515 static __be32 *p;
516 int space_left;
517 int frag1bytes, frag2bytes;
518
519 if (nbytes > PAGE_SIZE)
520 return NULL;
521 if (xdr->buf->len + nbytes > xdr->buf->buflen)
522 return NULL;
523 frag1bytes = (xdr->end - xdr->p) << 2;
524 frag2bytes = nbytes - frag1bytes;
525 if (xdr->iov)
526 xdr->iov->iov_len += frag1bytes;
527 else
528 xdr->buf->page_len += frag1bytes;
529 xdr->page_ptr++;
530 xdr->iov = NULL;
531
532
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536
537
538 xdr->scratch.iov_base = xdr->p;
539 xdr->scratch.iov_len = frag1bytes;
540 p = page_address(*xdr->page_ptr);
541
542
543
544
545 xdr->p = (void *)p + frag2bytes;
546 space_left = xdr->buf->buflen - xdr->buf->len;
547 xdr->end = (void *)p + min_t(int, space_left, PAGE_SIZE);
548 xdr->buf->page_len += frag2bytes;
549 xdr->buf->len += nbytes;
550 return p;
551}
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561
562__be32 * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes)
563{
564 __be32 *p = xdr->p;
565 __be32 *q;
566
567 xdr_commit_encode(xdr);
568
569 nbytes += 3;
570 nbytes &= ~3;
571 q = p + (nbytes >> 2);
572 if (unlikely(q > xdr->end || q < p))
573 return xdr_get_next_encode_buffer(xdr, nbytes);
574 xdr->p = q;
575 if (xdr->iov)
576 xdr->iov->iov_len += nbytes;
577 else
578 xdr->buf->page_len += nbytes;
579 xdr->buf->len += nbytes;
580 return p;
581}
582EXPORT_SYMBOL_GPL(xdr_reserve_space);
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603void xdr_truncate_encode(struct xdr_stream *xdr, size_t len)
604{
605 struct xdr_buf *buf = xdr->buf;
606 struct kvec *head = buf->head;
607 struct kvec *tail = buf->tail;
608 int fraglen;
609 int new;
610
611 if (len > buf->len) {
612 WARN_ON_ONCE(1);
613 return;
614 }
615 xdr_commit_encode(xdr);
616
617 fraglen = min_t(int, buf->len - len, tail->iov_len);
618 tail->iov_len -= fraglen;
619 buf->len -= fraglen;
620 if (tail->iov_len) {
621 xdr->p = tail->iov_base + tail->iov_len;
622 WARN_ON_ONCE(!xdr->end);
623 WARN_ON_ONCE(!xdr->iov);
624 return;
625 }
626 WARN_ON_ONCE(fraglen);
627 fraglen = min_t(int, buf->len - len, buf->page_len);
628 buf->page_len -= fraglen;
629 buf->len -= fraglen;
630
631 new = buf->page_base + buf->page_len;
632
633 xdr->page_ptr = buf->pages + (new >> PAGE_SHIFT);
634
635 if (buf->page_len) {
636 xdr->p = page_address(*xdr->page_ptr);
637 xdr->end = (void *)xdr->p + PAGE_SIZE;
638 xdr->p = (void *)xdr->p + (new % PAGE_SIZE);
639 WARN_ON_ONCE(xdr->iov);
640 return;
641 }
642 if (fraglen) {
643 xdr->end = head->iov_base + head->iov_len;
644 xdr->page_ptr--;
645 }
646
647 head->iov_len = len;
648 buf->len = len;
649 xdr->p = head->iov_base + head->iov_len;
650 xdr->iov = buf->head;
651}
652EXPORT_SYMBOL(xdr_truncate_encode);
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665
666int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen)
667{
668 struct xdr_buf *buf = xdr->buf;
669 int left_in_this_buf = (void *)xdr->end - (void *)xdr->p;
670 int end_offset = buf->len + left_in_this_buf;
671
672 if (newbuflen < 0 || newbuflen < buf->len)
673 return -1;
674 if (newbuflen > buf->buflen)
675 return 0;
676 if (newbuflen < end_offset)
677 xdr->end = (void *)xdr->end + newbuflen - end_offset;
678 buf->buflen = newbuflen;
679 return 0;
680}
681EXPORT_SYMBOL(xdr_restrict_buflen);
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690
691void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base,
692 unsigned int len)
693{
694 struct xdr_buf *buf = xdr->buf;
695 struct kvec *iov = buf->tail;
696 buf->pages = pages;
697 buf->page_base = base;
698 buf->page_len = len;
699
700 iov->iov_base = (char *)xdr->p;
701 iov->iov_len = 0;
702 xdr->iov = iov;
703
704 if (len & 3) {
705 unsigned int pad = 4 - (len & 3);
706
707 BUG_ON(xdr->p >= xdr->end);
708 iov->iov_base = (char *)xdr->p + (len & 3);
709 iov->iov_len += pad;
710 len += pad;
711 *xdr->p++ = 0;
712 }
713 buf->buflen += len;
714 buf->len += len;
715}
716EXPORT_SYMBOL_GPL(xdr_write_pages);
717
718static void xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov,
719 unsigned int len)
720{
721 if (len > iov->iov_len)
722 len = iov->iov_len;
723 xdr->p = (__be32*)iov->iov_base;
724 xdr->end = (__be32*)(iov->iov_base + len);
725 xdr->iov = iov;
726 xdr->page_ptr = NULL;
727}
728
729static int xdr_set_page_base(struct xdr_stream *xdr,
730 unsigned int base, unsigned int len)
731{
732 unsigned int pgnr;
733 unsigned int maxlen;
734 unsigned int pgoff;
735 unsigned int pgend;
736 void *kaddr;
737
738 maxlen = xdr->buf->page_len;
739 if (base >= maxlen)
740 return -EINVAL;
741 maxlen -= base;
742 if (len > maxlen)
743 len = maxlen;
744
745 base += xdr->buf->page_base;
746
747 pgnr = base >> PAGE_SHIFT;
748 xdr->page_ptr = &xdr->buf->pages[pgnr];
749 kaddr = page_address(*xdr->page_ptr);
750
751 pgoff = base & ~PAGE_MASK;
752 xdr->p = (__be32*)(kaddr + pgoff);
753
754 pgend = pgoff + len;
755 if (pgend > PAGE_SIZE)
756 pgend = PAGE_SIZE;
757 xdr->end = (__be32*)(kaddr + pgend);
758 xdr->iov = NULL;
759 return 0;
760}
761
762static void xdr_set_next_page(struct xdr_stream *xdr)
763{
764 unsigned int newbase;
765
766 newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT;
767 newbase -= xdr->buf->page_base;
768
769 if (xdr_set_page_base(xdr, newbase, PAGE_SIZE) < 0)
770 xdr_set_iov(xdr, xdr->buf->tail, xdr->buf->len);
771}
772
773static bool xdr_set_next_buffer(struct xdr_stream *xdr)
774{
775 if (xdr->page_ptr != NULL)
776 xdr_set_next_page(xdr);
777 else if (xdr->iov == xdr->buf->head) {
778 if (xdr_set_page_base(xdr, 0, PAGE_SIZE) < 0)
779 xdr_set_iov(xdr, xdr->buf->tail, xdr->buf->len);
780 }
781 return xdr->p != xdr->end;
782}
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789
790void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
791{
792 xdr->buf = buf;
793 xdr->scratch.iov_base = NULL;
794 xdr->scratch.iov_len = 0;
795 xdr->nwords = XDR_QUADLEN(buf->len);
796 if (buf->head[0].iov_len != 0)
797 xdr_set_iov(xdr, buf->head, buf->len);
798 else if (buf->page_len != 0)
799 xdr_set_page_base(xdr, 0, buf->len);
800 if (p != NULL && p > xdr->p && xdr->end >= p) {
801 xdr->nwords -= p - xdr->p;
802 xdr->p = p;
803 }
804}
805EXPORT_SYMBOL_GPL(xdr_init_decode);
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812
813
814void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
815 struct page **pages, unsigned int len)
816{
817 memset(buf, 0, sizeof(*buf));
818 buf->pages = pages;
819 buf->page_len = len;
820 buf->buflen = len;
821 buf->len = len;
822 xdr_init_decode(xdr, buf, NULL);
823}
824EXPORT_SYMBOL_GPL(xdr_init_decode_pages);
825
826static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
827{
828 unsigned int nwords = XDR_QUADLEN(nbytes);
829 __be32 *p = xdr->p;
830 __be32 *q = p + nwords;
831
832 if (unlikely(nwords > xdr->nwords || q > xdr->end || q < p))
833 return NULL;
834 xdr->p = q;
835 xdr->nwords -= nwords;
836 return p;
837}
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849
850void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
851{
852 xdr->scratch.iov_base = buf;
853 xdr->scratch.iov_len = buflen;
854}
855EXPORT_SYMBOL_GPL(xdr_set_scratch_buffer);
856
857static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes)
858{
859 __be32 *p;
860 void *cpdest = xdr->scratch.iov_base;
861 size_t cplen = (char *)xdr->end - (char *)xdr->p;
862
863 if (nbytes > xdr->scratch.iov_len)
864 return NULL;
865 memcpy(cpdest, xdr->p, cplen);
866 cpdest += cplen;
867 nbytes -= cplen;
868 if (!xdr_set_next_buffer(xdr))
869 return NULL;
870 p = __xdr_inline_decode(xdr, nbytes);
871 if (p == NULL)
872 return NULL;
873 memcpy(cpdest, p, nbytes);
874 return xdr->scratch.iov_base;
875}
876
877
878
879
880
881
882
883
884
885
886
887__be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
888{
889 __be32 *p;
890
891 if (nbytes == 0)
892 return xdr->p;
893 if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr))
894 return NULL;
895 p = __xdr_inline_decode(xdr, nbytes);
896 if (p != NULL)
897 return p;
898 return xdr_copy_to_scratch(xdr, nbytes);
899}
900EXPORT_SYMBOL_GPL(xdr_inline_decode);
901
902static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
903{
904 struct xdr_buf *buf = xdr->buf;
905 struct kvec *iov;
906 unsigned int nwords = XDR_QUADLEN(len);
907 unsigned int cur = xdr_stream_pos(xdr);
908
909 if (xdr->nwords == 0)
910 return 0;
911
912 iov = buf->head;
913 if (iov->iov_len > cur) {
914 xdr_shrink_bufhead(buf, iov->iov_len - cur);
915 xdr->nwords = XDR_QUADLEN(buf->len - cur);
916 }
917
918 if (nwords > xdr->nwords) {
919 nwords = xdr->nwords;
920 len = nwords << 2;
921 }
922 if (buf->page_len <= len)
923 len = buf->page_len;
924 else if (nwords < xdr->nwords) {
925
926 xdr_shrink_pagelen(buf, buf->page_len - len);
927 xdr->nwords = XDR_QUADLEN(buf->len - cur);
928 }
929 return len;
930}
931
932
933
934
935
936
937
938
939
940
941
942
943unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
944{
945 struct xdr_buf *buf = xdr->buf;
946 struct kvec *iov;
947 unsigned int nwords;
948 unsigned int end;
949 unsigned int padding;
950
951 len = xdr_align_pages(xdr, len);
952 if (len == 0)
953 return 0;
954 nwords = XDR_QUADLEN(len);
955 padding = (nwords << 2) - len;
956 xdr->iov = iov = buf->tail;
957
958 end = ((xdr->nwords - nwords) << 2) + padding;
959 if (end > iov->iov_len)
960 end = iov->iov_len;
961
962
963
964
965
966 xdr->p = (__be32 *)((char *)iov->iov_base + padding);
967 xdr->end = (__be32 *)((char *)iov->iov_base + end);
968 xdr->page_ptr = NULL;
969 xdr->nwords = XDR_QUADLEN(end - padding);
970 return len;
971}
972EXPORT_SYMBOL_GPL(xdr_read_pages);
973
974
975
976
977
978
979
980
981
982
983
984void xdr_enter_page(struct xdr_stream *xdr, unsigned int len)
985{
986 len = xdr_align_pages(xdr, len);
987
988
989
990
991 if (len != 0)
992 xdr_set_page_base(xdr, 0, len);
993}
994EXPORT_SYMBOL_GPL(xdr_enter_page);
995
996static struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0};
997
998void
999xdr_buf_from_iov(struct kvec *iov, struct xdr_buf *buf)
1000{
1001 buf->head[0] = *iov;
1002 buf->tail[0] = empty_iov;
1003 buf->page_len = 0;
1004 buf->buflen = buf->len = iov->iov_len;
1005}
1006EXPORT_SYMBOL_GPL(xdr_buf_from_iov);
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022int
1023xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
1024 unsigned int base, unsigned int len)
1025{
1026 subbuf->buflen = subbuf->len = len;
1027 if (base < buf->head[0].iov_len) {
1028 subbuf->head[0].iov_base = buf->head[0].iov_base + base;
1029 subbuf->head[0].iov_len = min_t(unsigned int, len,
1030 buf->head[0].iov_len - base);
1031 len -= subbuf->head[0].iov_len;
1032 base = 0;
1033 } else {
1034 base -= buf->head[0].iov_len;
1035 subbuf->head[0].iov_len = 0;
1036 }
1037
1038 if (base < buf->page_len) {
1039 subbuf->page_len = min(buf->page_len - base, len);
1040 base += buf->page_base;
1041 subbuf->page_base = base & ~PAGE_CACHE_MASK;
1042 subbuf->pages = &buf->pages[base >> PAGE_CACHE_SHIFT];
1043 len -= subbuf->page_len;
1044 base = 0;
1045 } else {
1046 base -= buf->page_len;
1047 subbuf->page_len = 0;
1048 }
1049
1050 if (base < buf->tail[0].iov_len) {
1051 subbuf->tail[0].iov_base = buf->tail[0].iov_base + base;
1052 subbuf->tail[0].iov_len = min_t(unsigned int, len,
1053 buf->tail[0].iov_len - base);
1054 len -= subbuf->tail[0].iov_len;
1055 base = 0;
1056 } else {
1057 base -= buf->tail[0].iov_len;
1058 subbuf->tail[0].iov_len = 0;
1059 }
1060
1061 if (base || len)
1062 return -1;
1063 return 0;
1064}
1065EXPORT_SYMBOL_GPL(xdr_buf_subsegment);
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077void xdr_buf_trim(struct xdr_buf *buf, unsigned int len)
1078{
1079 size_t cur;
1080 unsigned int trim = len;
1081
1082 if (buf->tail[0].iov_len) {
1083 cur = min_t(size_t, buf->tail[0].iov_len, trim);
1084 buf->tail[0].iov_len -= cur;
1085 trim -= cur;
1086 if (!trim)
1087 goto fix_len;
1088 }
1089
1090 if (buf->page_len) {
1091 cur = min_t(unsigned int, buf->page_len, trim);
1092 buf->page_len -= cur;
1093 trim -= cur;
1094 if (!trim)
1095 goto fix_len;
1096 }
1097
1098 if (buf->head[0].iov_len) {
1099 cur = min_t(size_t, buf->head[0].iov_len, trim);
1100 buf->head[0].iov_len -= cur;
1101 trim -= cur;
1102 }
1103fix_len:
1104 buf->len -= (len - trim);
1105}
1106EXPORT_SYMBOL_GPL(xdr_buf_trim);
1107
1108static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
1109{
1110 unsigned int this_len;
1111
1112 this_len = min_t(unsigned int, len, subbuf->head[0].iov_len);
1113 memcpy(obj, subbuf->head[0].iov_base, this_len);
1114 len -= this_len;
1115 obj += this_len;
1116 this_len = min_t(unsigned int, len, subbuf->page_len);
1117 if (this_len)
1118 _copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len);
1119 len -= this_len;
1120 obj += this_len;
1121 this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
1122 memcpy(obj, subbuf->tail[0].iov_base, this_len);
1123}
1124
1125
1126int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
1127{
1128 struct xdr_buf subbuf;
1129 int status;
1130
1131 status = xdr_buf_subsegment(buf, &subbuf, base, len);
1132 if (status != 0)
1133 return status;
1134 __read_bytes_from_xdr_buf(&subbuf, obj, len);
1135 return 0;
1136}
1137EXPORT_SYMBOL_GPL(read_bytes_from_xdr_buf);
1138
1139static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
1140{
1141 unsigned int this_len;
1142
1143 this_len = min_t(unsigned int, len, subbuf->head[0].iov_len);
1144 memcpy(subbuf->head[0].iov_base, obj, this_len);
1145 len -= this_len;
1146 obj += this_len;
1147 this_len = min_t(unsigned int, len, subbuf->page_len);
1148 if (this_len)
1149 _copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len);
1150 len -= this_len;
1151 obj += this_len;
1152 this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
1153 memcpy(subbuf->tail[0].iov_base, obj, this_len);
1154}
1155
1156
1157int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
1158{
1159 struct xdr_buf subbuf;
1160 int status;
1161
1162 status = xdr_buf_subsegment(buf, &subbuf, base, len);
1163 if (status != 0)
1164 return status;
1165 __write_bytes_to_xdr_buf(&subbuf, obj, len);
1166 return 0;
1167}
1168EXPORT_SYMBOL_GPL(write_bytes_to_xdr_buf);
1169
1170int
1171xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj)
1172{
1173 __be32 raw;
1174 int status;
1175
1176 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
1177 if (status)
1178 return status;
1179 *obj = be32_to_cpu(raw);
1180 return 0;
1181}
1182EXPORT_SYMBOL_GPL(xdr_decode_word);
1183
1184int
1185xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj)
1186{
1187 __be32 raw = cpu_to_be32(obj);
1188
1189 return write_bytes_to_xdr_buf(buf, base, &raw, sizeof(obj));
1190}
1191EXPORT_SYMBOL_GPL(xdr_encode_word);
1192
1193
1194
1195
1196
1197int xdr_buf_read_netobj(struct xdr_buf *buf, struct xdr_netobj *obj, unsigned int offset)
1198{
1199 struct xdr_buf subbuf;
1200
1201 if (xdr_decode_word(buf, offset, &obj->len))
1202 return -EFAULT;
1203 if (xdr_buf_subsegment(buf, &subbuf, offset + 4, obj->len))
1204 return -EFAULT;
1205
1206
1207 obj->data = subbuf.head[0].iov_base;
1208 if (subbuf.head[0].iov_len == obj->len)
1209 return 0;
1210
1211 obj->data = subbuf.tail[0].iov_base;
1212 if (subbuf.tail[0].iov_len == obj->len)
1213 return 0;
1214
1215
1216
1217
1218
1219
1220 if (obj->len > buf->buflen - buf->len)
1221 return -ENOMEM;
1222 if (buf->tail[0].iov_len != 0)
1223 obj->data = buf->tail[0].iov_base + buf->tail[0].iov_len;
1224 else
1225 obj->data = buf->head[0].iov_base + buf->head[0].iov_len;
1226 __read_bytes_from_xdr_buf(&subbuf, obj->data, obj->len);
1227 return 0;
1228}
1229EXPORT_SYMBOL_GPL(xdr_buf_read_netobj);
1230
1231
1232static int
1233xdr_xcode_array2(struct xdr_buf *buf, unsigned int base,
1234 struct xdr_array2_desc *desc, int encode)
1235{
1236 char *elem = NULL, *c;
1237 unsigned int copied = 0, todo, avail_here;
1238 struct page **ppages = NULL;
1239 int err;
1240
1241 if (encode) {
1242 if (xdr_encode_word(buf, base, desc->array_len) != 0)
1243 return -EINVAL;
1244 } else {
1245 if (xdr_decode_word(buf, base, &desc->array_len) != 0 ||
1246 desc->array_len > desc->array_maxlen ||
1247 (unsigned long) base + 4 + desc->array_len *
1248 desc->elem_size > buf->len)
1249 return -EINVAL;
1250 }
1251 base += 4;
1252
1253 if (!desc->xcode)
1254 return 0;
1255
1256 todo = desc->array_len * desc->elem_size;
1257
1258
1259 if (todo && base < buf->head->iov_len) {
1260 c = buf->head->iov_base + base;
1261 avail_here = min_t(unsigned int, todo,
1262 buf->head->iov_len - base);
1263 todo -= avail_here;
1264
1265 while (avail_here >= desc->elem_size) {
1266 err = desc->xcode(desc, c);
1267 if (err)
1268 goto out;
1269 c += desc->elem_size;
1270 avail_here -= desc->elem_size;
1271 }
1272 if (avail_here) {
1273 if (!elem) {
1274 elem = kmalloc(desc->elem_size, GFP_KERNEL);
1275 err = -ENOMEM;
1276 if (!elem)
1277 goto out;
1278 }
1279 if (encode) {
1280 err = desc->xcode(desc, elem);
1281 if (err)
1282 goto out;
1283 memcpy(c, elem, avail_here);
1284 } else
1285 memcpy(elem, c, avail_here);
1286 copied = avail_here;
1287 }
1288 base = buf->head->iov_len;
1289 }
1290
1291
1292 base -= buf->head->iov_len;
1293 if (todo && base < buf->page_len) {
1294 unsigned int avail_page;
1295
1296 avail_here = min(todo, buf->page_len - base);
1297 todo -= avail_here;
1298
1299 base += buf->page_base;
1300 ppages = buf->pages + (base >> PAGE_CACHE_SHIFT);
1301 base &= ~PAGE_CACHE_MASK;
1302 avail_page = min_t(unsigned int, PAGE_CACHE_SIZE - base,
1303 avail_here);
1304 c = kmap(*ppages) + base;
1305
1306 while (avail_here) {
1307 avail_here -= avail_page;
1308 if (copied || avail_page < desc->elem_size) {
1309 unsigned int l = min(avail_page,
1310 desc->elem_size - copied);
1311 if (!elem) {
1312 elem = kmalloc(desc->elem_size,
1313 GFP_KERNEL);
1314 err = -ENOMEM;
1315 if (!elem)
1316 goto out;
1317 }
1318 if (encode) {
1319 if (!copied) {
1320 err = desc->xcode(desc, elem);
1321 if (err)
1322 goto out;
1323 }
1324 memcpy(c, elem + copied, l);
1325 copied += l;
1326 if (copied == desc->elem_size)
1327 copied = 0;
1328 } else {
1329 memcpy(elem + copied, c, l);
1330 copied += l;
1331 if (copied == desc->elem_size) {
1332 err = desc->xcode(desc, elem);
1333 if (err)
1334 goto out;
1335 copied = 0;
1336 }
1337 }
1338 avail_page -= l;
1339 c += l;
1340 }
1341 while (avail_page >= desc->elem_size) {
1342 err = desc->xcode(desc, c);
1343 if (err)
1344 goto out;
1345 c += desc->elem_size;
1346 avail_page -= desc->elem_size;
1347 }
1348 if (avail_page) {
1349 unsigned int l = min(avail_page,
1350 desc->elem_size - copied);
1351 if (!elem) {
1352 elem = kmalloc(desc->elem_size,
1353 GFP_KERNEL);
1354 err = -ENOMEM;
1355 if (!elem)
1356 goto out;
1357 }
1358 if (encode) {
1359 if (!copied) {
1360 err = desc->xcode(desc, elem);
1361 if (err)
1362 goto out;
1363 }
1364 memcpy(c, elem + copied, l);
1365 copied += l;
1366 if (copied == desc->elem_size)
1367 copied = 0;
1368 } else {
1369 memcpy(elem + copied, c, l);
1370 copied += l;
1371 if (copied == desc->elem_size) {
1372 err = desc->xcode(desc, elem);
1373 if (err)
1374 goto out;
1375 copied = 0;
1376 }
1377 }
1378 }
1379 if (avail_here) {
1380 kunmap(*ppages);
1381 ppages++;
1382 c = kmap(*ppages);
1383 }
1384
1385 avail_page = min(avail_here,
1386 (unsigned int) PAGE_CACHE_SIZE);
1387 }
1388 base = buf->page_len;
1389 }
1390
1391
1392 base -= buf->page_len;
1393 if (todo) {
1394 c = buf->tail->iov_base + base;
1395 if (copied) {
1396 unsigned int l = desc->elem_size - copied;
1397
1398 if (encode)
1399 memcpy(c, elem + copied, l);
1400 else {
1401 memcpy(elem + copied, c, l);
1402 err = desc->xcode(desc, elem);
1403 if (err)
1404 goto out;
1405 }
1406 todo -= l;
1407 c += l;
1408 }
1409 while (todo) {
1410 err = desc->xcode(desc, c);
1411 if (err)
1412 goto out;
1413 c += desc->elem_size;
1414 todo -= desc->elem_size;
1415 }
1416 }
1417 err = 0;
1418
1419out:
1420 kfree(elem);
1421 if (ppages)
1422 kunmap(*ppages);
1423 return err;
1424}
1425
1426int
1427xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
1428 struct xdr_array2_desc *desc)
1429{
1430 if (base >= buf->len)
1431 return -EINVAL;
1432
1433 return xdr_xcode_array2(buf, base, desc, 0);
1434}
1435EXPORT_SYMBOL_GPL(xdr_decode_array2);
1436
1437int
1438xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
1439 struct xdr_array2_desc *desc)
1440{
1441 if ((unsigned long) base + 4 + desc->array_len * desc->elem_size >
1442 buf->head->iov_len + buf->page_len + buf->tail->iov_len)
1443 return -EINVAL;
1444
1445 return xdr_xcode_array2(buf, base, desc, 1);
1446}
1447EXPORT_SYMBOL_GPL(xdr_encode_array2);
1448
1449int
1450xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len,
1451 int (*actor)(struct scatterlist *, void *), void *data)
1452{
1453 int i, ret = 0;
1454 unsigned int page_len, thislen, page_offset;
1455 struct scatterlist sg[1];
1456
1457 sg_init_table(sg, 1);
1458
1459 if (offset >= buf->head[0].iov_len) {
1460 offset -= buf->head[0].iov_len;
1461 } else {
1462 thislen = buf->head[0].iov_len - offset;
1463 if (thislen > len)
1464 thislen = len;
1465 sg_set_buf(sg, buf->head[0].iov_base + offset, thislen);
1466 ret = actor(sg, data);
1467 if (ret)
1468 goto out;
1469 offset = 0;
1470 len -= thislen;
1471 }
1472 if (len == 0)
1473 goto out;
1474
1475 if (offset >= buf->page_len) {
1476 offset -= buf->page_len;
1477 } else {
1478 page_len = buf->page_len - offset;
1479 if (page_len > len)
1480 page_len = len;
1481 len -= page_len;
1482 page_offset = (offset + buf->page_base) & (PAGE_CACHE_SIZE - 1);
1483 i = (offset + buf->page_base) >> PAGE_CACHE_SHIFT;
1484 thislen = PAGE_CACHE_SIZE - page_offset;
1485 do {
1486 if (thislen > page_len)
1487 thislen = page_len;
1488 sg_set_page(sg, buf->pages[i], thislen, page_offset);
1489 ret = actor(sg, data);
1490 if (ret)
1491 goto out;
1492 page_len -= thislen;
1493 i++;
1494 page_offset = 0;
1495 thislen = PAGE_CACHE_SIZE;
1496 } while (page_len != 0);
1497 offset = 0;
1498 }
1499 if (len == 0)
1500 goto out;
1501 if (offset < buf->tail[0].iov_len) {
1502 thislen = buf->tail[0].iov_len - offset;
1503 if (thislen > len)
1504 thislen = len;
1505 sg_set_buf(sg, buf->tail[0].iov_base + offset, thislen);
1506 ret = actor(sg, data);
1507 len -= thislen;
1508 }
1509 if (len != 0)
1510 ret = -EINVAL;
1511out:
1512 return ret;
1513}
1514EXPORT_SYMBOL_GPL(xdr_process_buf);
1515
1516