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10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/types.h>
13#include <linux/string.h>
14#include <linux/kernel.h>
15#include <linux/pagemap.h>
16#include <linux/errno.h>
17#include <linux/sunrpc/xdr.h>
18#include <linux/sunrpc/msg_prot.h>
19#include <linux/bvec.h>
20#include <trace/events/sunrpc.h>
21
22
23
24
25__be32 *
26xdr_encode_netobj(__be32 *p, const struct xdr_netobj *obj)
27{
28 unsigned int quadlen = XDR_QUADLEN(obj->len);
29
30 p[quadlen] = 0;
31 *p++ = cpu_to_be32(obj->len);
32 memcpy(p, obj->data, obj->len);
33 return p + XDR_QUADLEN(obj->len);
34}
35EXPORT_SYMBOL_GPL(xdr_encode_netobj);
36
37__be32 *
38xdr_decode_netobj(__be32 *p, struct xdr_netobj *obj)
39{
40 unsigned int len;
41
42 if ((len = be32_to_cpu(*p++)) > XDR_MAX_NETOBJ)
43 return NULL;
44 obj->len = len;
45 obj->data = (u8 *) p;
46 return p + XDR_QUADLEN(len);
47}
48EXPORT_SYMBOL_GPL(xdr_decode_netobj);
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63
64__be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int nbytes)
65{
66 if (likely(nbytes != 0)) {
67 unsigned int quadlen = XDR_QUADLEN(nbytes);
68 unsigned int padding = (quadlen << 2) - nbytes;
69
70 if (ptr != NULL)
71 memcpy(p, ptr, nbytes);
72 if (padding != 0)
73 memset((char *)p + nbytes, 0, padding);
74 p += quadlen;
75 }
76 return p;
77}
78EXPORT_SYMBOL_GPL(xdr_encode_opaque_fixed);
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85
86
87
88__be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int nbytes)
89{
90 *p++ = cpu_to_be32(nbytes);
91 return xdr_encode_opaque_fixed(p, ptr, nbytes);
92}
93EXPORT_SYMBOL_GPL(xdr_encode_opaque);
94
95__be32 *
96xdr_encode_string(__be32 *p, const char *string)
97{
98 return xdr_encode_array(p, string, strlen(string));
99}
100EXPORT_SYMBOL_GPL(xdr_encode_string);
101
102__be32 *
103xdr_decode_string_inplace(__be32 *p, char **sp,
104 unsigned int *lenp, unsigned int maxlen)
105{
106 u32 len;
107
108 len = be32_to_cpu(*p++);
109 if (len > maxlen)
110 return NULL;
111 *lenp = len;
112 *sp = (char *) p;
113 return p + XDR_QUADLEN(len);
114}
115EXPORT_SYMBOL_GPL(xdr_decode_string_inplace);
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121
122
123void
124xdr_terminate_string(struct xdr_buf *buf, const u32 len)
125{
126 char *kaddr;
127
128 kaddr = kmap_atomic(buf->pages[0]);
129 kaddr[buf->page_base + len] = '\0';
130 kunmap_atomic(kaddr);
131}
132EXPORT_SYMBOL_GPL(xdr_terminate_string);
133
134size_t
135xdr_buf_pagecount(struct xdr_buf *buf)
136{
137 if (!buf->page_len)
138 return 0;
139 return (buf->page_base + buf->page_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
140}
141
142int
143xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp)
144{
145 size_t i, n = xdr_buf_pagecount(buf);
146
147 if (n != 0 && buf->bvec == NULL) {
148 buf->bvec = kmalloc_array(n, sizeof(buf->bvec[0]), gfp);
149 if (!buf->bvec)
150 return -ENOMEM;
151 for (i = 0; i < n; i++) {
152 buf->bvec[i].bv_page = buf->pages[i];
153 buf->bvec[i].bv_len = PAGE_SIZE;
154 buf->bvec[i].bv_offset = 0;
155 }
156 }
157 return 0;
158}
159
160void
161xdr_free_bvec(struct xdr_buf *buf)
162{
163 kfree(buf->bvec);
164 buf->bvec = NULL;
165}
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175
176void
177xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset,
178 struct page **pages, unsigned int base, unsigned int len)
179{
180 struct kvec *head = xdr->head;
181 struct kvec *tail = xdr->tail;
182 char *buf = (char *)head->iov_base;
183 unsigned int buflen = head->iov_len;
184
185 head->iov_len = offset;
186
187 xdr->pages = pages;
188 xdr->page_base = base;
189 xdr->page_len = len;
190
191 tail->iov_base = buf + offset;
192 tail->iov_len = buflen - offset;
193 if ((xdr->page_len & 3) == 0)
194 tail->iov_len -= sizeof(__be32);
195
196 xdr->buflen += len;
197}
198EXPORT_SYMBOL_GPL(xdr_inline_pages);
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217
218static void
219_shift_data_right_pages(struct page **pages, size_t pgto_base,
220 size_t pgfrom_base, size_t len)
221{
222 struct page **pgfrom, **pgto;
223 char *vfrom, *vto;
224 size_t copy;
225
226 BUG_ON(pgto_base <= pgfrom_base);
227
228 pgto_base += len;
229 pgfrom_base += len;
230
231 pgto = pages + (pgto_base >> PAGE_SHIFT);
232 pgfrom = pages + (pgfrom_base >> PAGE_SHIFT);
233
234 pgto_base &= ~PAGE_MASK;
235 pgfrom_base &= ~PAGE_MASK;
236
237 do {
238
239 if (pgto_base == 0) {
240 pgto_base = PAGE_SIZE;
241 pgto--;
242 }
243 if (pgfrom_base == 0) {
244 pgfrom_base = PAGE_SIZE;
245 pgfrom--;
246 }
247
248 copy = len;
249 if (copy > pgto_base)
250 copy = pgto_base;
251 if (copy > pgfrom_base)
252 copy = pgfrom_base;
253 pgto_base -= copy;
254 pgfrom_base -= copy;
255
256 vto = kmap_atomic(*pgto);
257 if (*pgto != *pgfrom) {
258 vfrom = kmap_atomic(*pgfrom);
259 memcpy(vto + pgto_base, vfrom + pgfrom_base, copy);
260 kunmap_atomic(vfrom);
261 } else
262 memmove(vto + pgto_base, vto + pgfrom_base, copy);
263 flush_dcache_page(*pgto);
264 kunmap_atomic(vto);
265
266 } while ((len -= copy) != 0);
267}
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278
279static void
280_copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
281{
282 struct page **pgto;
283 char *vto;
284 size_t copy;
285
286 pgto = pages + (pgbase >> PAGE_SHIFT);
287 pgbase &= ~PAGE_MASK;
288
289 for (;;) {
290 copy = PAGE_SIZE - pgbase;
291 if (copy > len)
292 copy = len;
293
294 vto = kmap_atomic(*pgto);
295 memcpy(vto + pgbase, p, copy);
296 kunmap_atomic(vto);
297
298 len -= copy;
299 if (len == 0)
300 break;
301
302 pgbase += copy;
303 if (pgbase == PAGE_SIZE) {
304 flush_dcache_page(*pgto);
305 pgbase = 0;
306 pgto++;
307 }
308 p += copy;
309 }
310 flush_dcache_page(*pgto);
311}
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322
323void
324_copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
325{
326 struct page **pgfrom;
327 char *vfrom;
328 size_t copy;
329
330 pgfrom = pages + (pgbase >> PAGE_SHIFT);
331 pgbase &= ~PAGE_MASK;
332
333 do {
334 copy = PAGE_SIZE - pgbase;
335 if (copy > len)
336 copy = len;
337
338 vfrom = kmap_atomic(*pgfrom);
339 memcpy(p, vfrom + pgbase, copy);
340 kunmap_atomic(vfrom);
341
342 pgbase += copy;
343 if (pgbase == PAGE_SIZE) {
344 pgbase = 0;
345 pgfrom++;
346 }
347 p += copy;
348
349 } while ((len -= copy) != 0);
350}
351EXPORT_SYMBOL_GPL(_copy_from_pages);
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361
362static unsigned int
363xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
364{
365 struct kvec *head, *tail;
366 size_t copy, offs;
367 unsigned int pglen = buf->page_len;
368 unsigned int result;
369
370 result = 0;
371 tail = buf->tail;
372 head = buf->head;
373
374 WARN_ON_ONCE(len > head->iov_len);
375 if (len > head->iov_len)
376 len = head->iov_len;
377
378
379 if (tail->iov_len != 0) {
380 if (tail->iov_len > len) {
381 copy = tail->iov_len - len;
382 memmove((char *)tail->iov_base + len,
383 tail->iov_base, copy);
384 result += copy;
385 }
386
387 copy = len;
388 if (copy > pglen)
389 copy = pglen;
390 offs = len - copy;
391 if (offs >= tail->iov_len)
392 copy = 0;
393 else if (copy > tail->iov_len - offs)
394 copy = tail->iov_len - offs;
395 if (copy != 0) {
396 _copy_from_pages((char *)tail->iov_base + offs,
397 buf->pages,
398 buf->page_base + pglen + offs - len,
399 copy);
400 result += copy;
401 }
402
403 if (len > pglen) {
404 offs = copy = len - pglen;
405 if (copy > tail->iov_len)
406 copy = tail->iov_len;
407 memcpy(tail->iov_base,
408 (char *)head->iov_base +
409 head->iov_len - offs,
410 copy);
411 result += copy;
412 }
413 }
414
415 if (pglen != 0) {
416 if (pglen > len)
417 _shift_data_right_pages(buf->pages,
418 buf->page_base + len,
419 buf->page_base,
420 pglen - len);
421 copy = len;
422 if (len > pglen)
423 copy = pglen;
424 _copy_to_pages(buf->pages, buf->page_base,
425 (char *)head->iov_base + head->iov_len - len,
426 copy);
427 result += copy;
428 }
429 head->iov_len -= len;
430 buf->buflen -= len;
431
432 if (buf->len > buf->buflen)
433 buf->len = buf->buflen;
434
435 return result;
436}
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446
447static unsigned int
448xdr_shrink_pagelen(struct xdr_buf *buf, size_t len)
449{
450 struct kvec *tail;
451 size_t copy;
452 unsigned int pglen = buf->page_len;
453 unsigned int tailbuf_len;
454 unsigned int result;
455
456 result = 0;
457 tail = buf->tail;
458 BUG_ON (len > pglen);
459
460 tailbuf_len = buf->buflen - buf->head->iov_len - buf->page_len;
461
462
463 if (tailbuf_len != 0) {
464 unsigned int free_space = tailbuf_len - tail->iov_len;
465
466 if (len < free_space)
467 free_space = len;
468 tail->iov_len += free_space;
469
470 copy = len;
471 if (tail->iov_len > len) {
472 char *p = (char *)tail->iov_base + len;
473 memmove(p, tail->iov_base, tail->iov_len - len);
474 result += tail->iov_len - len;
475 } else
476 copy = tail->iov_len;
477
478 _copy_from_pages((char *)tail->iov_base,
479 buf->pages, buf->page_base + pglen - len,
480 copy);
481 result += copy;
482 }
483 buf->page_len -= len;
484 buf->buflen -= len;
485
486 if (buf->len > buf->buflen)
487 buf->len = buf->buflen;
488
489 return result;
490}
491
492void
493xdr_shift_buf(struct xdr_buf *buf, size_t len)
494{
495 xdr_shrink_bufhead(buf, len);
496}
497EXPORT_SYMBOL_GPL(xdr_shift_buf);
498
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502
503unsigned int xdr_stream_pos(const struct xdr_stream *xdr)
504{
505 return (unsigned int)(XDR_QUADLEN(xdr->buf->len) - xdr->nwords) << 2;
506}
507EXPORT_SYMBOL_GPL(xdr_stream_pos);
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523void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
524 struct rpc_rqst *rqst)
525{
526 struct kvec *iov = buf->head;
527 int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len;
528
529 xdr_set_scratch_buffer(xdr, NULL, 0);
530 BUG_ON(scratch_len < 0);
531 xdr->buf = buf;
532 xdr->iov = iov;
533 xdr->p = (__be32 *)((char *)iov->iov_base + iov->iov_len);
534 xdr->end = (__be32 *)((char *)iov->iov_base + scratch_len);
535 BUG_ON(iov->iov_len > scratch_len);
536
537 if (p != xdr->p && p != NULL) {
538 size_t len;
539
540 BUG_ON(p < xdr->p || p > xdr->end);
541 len = (char *)p - (char *)xdr->p;
542 xdr->p = p;
543 buf->len += len;
544 iov->iov_len += len;
545 }
546 xdr->rqst = rqst;
547}
548EXPORT_SYMBOL_GPL(xdr_init_encode);
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563void xdr_commit_encode(struct xdr_stream *xdr)
564{
565 int shift = xdr->scratch.iov_len;
566 void *page;
567
568 if (shift == 0)
569 return;
570 page = page_address(*xdr->page_ptr);
571 memcpy(xdr->scratch.iov_base, page, shift);
572 memmove(page, page + shift, (void *)xdr->p - page);
573 xdr->scratch.iov_len = 0;
574}
575EXPORT_SYMBOL_GPL(xdr_commit_encode);
576
577static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr,
578 size_t nbytes)
579{
580 __be32 *p;
581 int space_left;
582 int frag1bytes, frag2bytes;
583
584 if (nbytes > PAGE_SIZE)
585 goto out_overflow;
586 if (xdr->buf->len + nbytes > xdr->buf->buflen)
587 goto out_overflow;
588 frag1bytes = (xdr->end - xdr->p) << 2;
589 frag2bytes = nbytes - frag1bytes;
590 if (xdr->iov)
591 xdr->iov->iov_len += frag1bytes;
592 else
593 xdr->buf->page_len += frag1bytes;
594 xdr->page_ptr++;
595 xdr->iov = NULL;
596
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601
602
603 xdr->scratch.iov_base = xdr->p;
604 xdr->scratch.iov_len = frag1bytes;
605 p = page_address(*xdr->page_ptr);
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609
610 xdr->p = (void *)p + frag2bytes;
611 space_left = xdr->buf->buflen - xdr->buf->len;
612 xdr->end = (void *)p + min_t(int, space_left, PAGE_SIZE);
613 xdr->buf->page_len += frag2bytes;
614 xdr->buf->len += nbytes;
615 return p;
616out_overflow:
617 trace_rpc_xdr_overflow(xdr, nbytes);
618 return NULL;
619}
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629
630__be32 * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes)
631{
632 __be32 *p = xdr->p;
633 __be32 *q;
634
635 xdr_commit_encode(xdr);
636
637 nbytes += 3;
638 nbytes &= ~3;
639 q = p + (nbytes >> 2);
640 if (unlikely(q > xdr->end || q < p))
641 return xdr_get_next_encode_buffer(xdr, nbytes);
642 xdr->p = q;
643 if (xdr->iov)
644 xdr->iov->iov_len += nbytes;
645 else
646 xdr->buf->page_len += nbytes;
647 xdr->buf->len += nbytes;
648 return p;
649}
650EXPORT_SYMBOL_GPL(xdr_reserve_space);
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671void xdr_truncate_encode(struct xdr_stream *xdr, size_t len)
672{
673 struct xdr_buf *buf = xdr->buf;
674 struct kvec *head = buf->head;
675 struct kvec *tail = buf->tail;
676 int fraglen;
677 int new;
678
679 if (len > buf->len) {
680 WARN_ON_ONCE(1);
681 return;
682 }
683 xdr_commit_encode(xdr);
684
685 fraglen = min_t(int, buf->len - len, tail->iov_len);
686 tail->iov_len -= fraglen;
687 buf->len -= fraglen;
688 if (tail->iov_len) {
689 xdr->p = tail->iov_base + tail->iov_len;
690 WARN_ON_ONCE(!xdr->end);
691 WARN_ON_ONCE(!xdr->iov);
692 return;
693 }
694 WARN_ON_ONCE(fraglen);
695 fraglen = min_t(int, buf->len - len, buf->page_len);
696 buf->page_len -= fraglen;
697 buf->len -= fraglen;
698
699 new = buf->page_base + buf->page_len;
700
701 xdr->page_ptr = buf->pages + (new >> PAGE_SHIFT);
702
703 if (buf->page_len) {
704 xdr->p = page_address(*xdr->page_ptr);
705 xdr->end = (void *)xdr->p + PAGE_SIZE;
706 xdr->p = (void *)xdr->p + (new % PAGE_SIZE);
707 WARN_ON_ONCE(xdr->iov);
708 return;
709 }
710 if (fraglen)
711 xdr->end = head->iov_base + head->iov_len;
712
713 xdr->page_ptr--;
714 head->iov_len = len;
715 buf->len = len;
716 xdr->p = head->iov_base + head->iov_len;
717 xdr->iov = buf->head;
718}
719EXPORT_SYMBOL(xdr_truncate_encode);
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733int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen)
734{
735 struct xdr_buf *buf = xdr->buf;
736 int left_in_this_buf = (void *)xdr->end - (void *)xdr->p;
737 int end_offset = buf->len + left_in_this_buf;
738
739 if (newbuflen < 0 || newbuflen < buf->len)
740 return -1;
741 if (newbuflen > buf->buflen)
742 return 0;
743 if (newbuflen < end_offset)
744 xdr->end = (void *)xdr->end + newbuflen - end_offset;
745 buf->buflen = newbuflen;
746 return 0;
747}
748EXPORT_SYMBOL(xdr_restrict_buflen);
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758void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base,
759 unsigned int len)
760{
761 struct xdr_buf *buf = xdr->buf;
762 struct kvec *iov = buf->tail;
763 buf->pages = pages;
764 buf->page_base = base;
765 buf->page_len = len;
766
767 iov->iov_base = (char *)xdr->p;
768 iov->iov_len = 0;
769 xdr->iov = iov;
770
771 if (len & 3) {
772 unsigned int pad = 4 - (len & 3);
773
774 BUG_ON(xdr->p >= xdr->end);
775 iov->iov_base = (char *)xdr->p + (len & 3);
776 iov->iov_len += pad;
777 len += pad;
778 *xdr->p++ = 0;
779 }
780 buf->buflen += len;
781 buf->len += len;
782}
783EXPORT_SYMBOL_GPL(xdr_write_pages);
784
785static void xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov,
786 unsigned int len)
787{
788 if (len > iov->iov_len)
789 len = iov->iov_len;
790 xdr->p = (__be32*)iov->iov_base;
791 xdr->end = (__be32*)(iov->iov_base + len);
792 xdr->iov = iov;
793 xdr->page_ptr = NULL;
794}
795
796static int xdr_set_page_base(struct xdr_stream *xdr,
797 unsigned int base, unsigned int len)
798{
799 unsigned int pgnr;
800 unsigned int maxlen;
801 unsigned int pgoff;
802 unsigned int pgend;
803 void *kaddr;
804
805 maxlen = xdr->buf->page_len;
806 if (base >= maxlen)
807 return -EINVAL;
808 maxlen -= base;
809 if (len > maxlen)
810 len = maxlen;
811
812 base += xdr->buf->page_base;
813
814 pgnr = base >> PAGE_SHIFT;
815 xdr->page_ptr = &xdr->buf->pages[pgnr];
816 kaddr = page_address(*xdr->page_ptr);
817
818 pgoff = base & ~PAGE_MASK;
819 xdr->p = (__be32*)(kaddr + pgoff);
820
821 pgend = pgoff + len;
822 if (pgend > PAGE_SIZE)
823 pgend = PAGE_SIZE;
824 xdr->end = (__be32*)(kaddr + pgend);
825 xdr->iov = NULL;
826 return 0;
827}
828
829static void xdr_set_next_page(struct xdr_stream *xdr)
830{
831 unsigned int newbase;
832
833 newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT;
834 newbase -= xdr->buf->page_base;
835
836 if (xdr_set_page_base(xdr, newbase, PAGE_SIZE) < 0)
837 xdr_set_iov(xdr, xdr->buf->tail, xdr->nwords << 2);
838}
839
840static bool xdr_set_next_buffer(struct xdr_stream *xdr)
841{
842 if (xdr->page_ptr != NULL)
843 xdr_set_next_page(xdr);
844 else if (xdr->iov == xdr->buf->head) {
845 if (xdr_set_page_base(xdr, 0, PAGE_SIZE) < 0)
846 xdr_set_iov(xdr, xdr->buf->tail, xdr->nwords << 2);
847 }
848 return xdr->p != xdr->end;
849}
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858void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
859 struct rpc_rqst *rqst)
860{
861 xdr->buf = buf;
862 xdr->scratch.iov_base = NULL;
863 xdr->scratch.iov_len = 0;
864 xdr->nwords = XDR_QUADLEN(buf->len);
865 if (buf->head[0].iov_len != 0)
866 xdr_set_iov(xdr, buf->head, buf->len);
867 else if (buf->page_len != 0)
868 xdr_set_page_base(xdr, 0, buf->len);
869 else
870 xdr_set_iov(xdr, buf->head, buf->len);
871 if (p != NULL && p > xdr->p && xdr->end >= p) {
872 xdr->nwords -= p - xdr->p;
873 xdr->p = p;
874 }
875 xdr->rqst = rqst;
876}
877EXPORT_SYMBOL_GPL(xdr_init_decode);
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884
885
886void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
887 struct page **pages, unsigned int len)
888{
889 memset(buf, 0, sizeof(*buf));
890 buf->pages = pages;
891 buf->page_len = len;
892 buf->buflen = len;
893 buf->len = len;
894 xdr_init_decode(xdr, buf, NULL, NULL);
895}
896EXPORT_SYMBOL_GPL(xdr_init_decode_pages);
897
898static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
899{
900 unsigned int nwords = XDR_QUADLEN(nbytes);
901 __be32 *p = xdr->p;
902 __be32 *q = p + nwords;
903
904 if (unlikely(nwords > xdr->nwords || q > xdr->end || q < p))
905 return NULL;
906 xdr->p = q;
907 xdr->nwords -= nwords;
908 return p;
909}
910
911
912
913
914
915
916
917
918
919
920
921
922void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
923{
924 xdr->scratch.iov_base = buf;
925 xdr->scratch.iov_len = buflen;
926}
927EXPORT_SYMBOL_GPL(xdr_set_scratch_buffer);
928
929static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes)
930{
931 __be32 *p;
932 char *cpdest = xdr->scratch.iov_base;
933 size_t cplen = (char *)xdr->end - (char *)xdr->p;
934
935 if (nbytes > xdr->scratch.iov_len)
936 goto out_overflow;
937 p = __xdr_inline_decode(xdr, cplen);
938 if (p == NULL)
939 return NULL;
940 memcpy(cpdest, p, cplen);
941 if (!xdr_set_next_buffer(xdr))
942 goto out_overflow;
943 cpdest += cplen;
944 nbytes -= cplen;
945 p = __xdr_inline_decode(xdr, nbytes);
946 if (p == NULL)
947 return NULL;
948 memcpy(cpdest, p, nbytes);
949 return xdr->scratch.iov_base;
950out_overflow:
951 trace_rpc_xdr_overflow(xdr, nbytes);
952 return NULL;
953}
954
955
956
957
958
959
960
961
962
963
964
965__be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
966{
967 __be32 *p;
968
969 if (unlikely(nbytes == 0))
970 return xdr->p;
971 if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr))
972 goto out_overflow;
973 p = __xdr_inline_decode(xdr, nbytes);
974 if (p != NULL)
975 return p;
976 return xdr_copy_to_scratch(xdr, nbytes);
977out_overflow:
978 trace_rpc_xdr_overflow(xdr, nbytes);
979 return NULL;
980}
981EXPORT_SYMBOL_GPL(xdr_inline_decode);
982
983static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
984{
985 struct xdr_buf *buf = xdr->buf;
986 struct kvec *iov;
987 unsigned int nwords = XDR_QUADLEN(len);
988 unsigned int cur = xdr_stream_pos(xdr);
989 unsigned int copied, offset;
990
991 if (xdr->nwords == 0)
992 return 0;
993
994
995 iov = buf->head;
996 if (iov->iov_len > cur) {
997 offset = iov->iov_len - cur;
998 copied = xdr_shrink_bufhead(buf, offset);
999 trace_rpc_xdr_alignment(xdr, offset, copied);
1000 xdr->nwords = XDR_QUADLEN(buf->len - cur);
1001 }
1002
1003 if (nwords > xdr->nwords) {
1004 nwords = xdr->nwords;
1005 len = nwords << 2;
1006 }
1007 if (buf->page_len <= len)
1008 len = buf->page_len;
1009 else if (nwords < xdr->nwords) {
1010
1011 offset = buf->page_len - len;
1012 copied = xdr_shrink_pagelen(buf, offset);
1013 trace_rpc_xdr_alignment(xdr, offset, copied);
1014 xdr->nwords = XDR_QUADLEN(buf->len - cur);
1015 }
1016 return len;
1017}
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len)
1031{
1032 struct xdr_buf *buf = xdr->buf;
1033 struct kvec *iov;
1034 unsigned int nwords;
1035 unsigned int end;
1036 unsigned int padding;
1037
1038 len = xdr_align_pages(xdr, len);
1039 if (len == 0)
1040 return 0;
1041 nwords = XDR_QUADLEN(len);
1042 padding = (nwords << 2) - len;
1043 xdr->iov = iov = buf->tail;
1044
1045 end = ((xdr->nwords - nwords) << 2) + padding;
1046 if (end > iov->iov_len)
1047 end = iov->iov_len;
1048
1049
1050
1051
1052
1053 xdr->p = (__be32 *)((char *)iov->iov_base + padding);
1054 xdr->end = (__be32 *)((char *)iov->iov_base + end);
1055 xdr->page_ptr = NULL;
1056 xdr->nwords = XDR_QUADLEN(end - padding);
1057 return len;
1058}
1059EXPORT_SYMBOL_GPL(xdr_read_pages);
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071void xdr_enter_page(struct xdr_stream *xdr, unsigned int len)
1072{
1073 len = xdr_align_pages(xdr, len);
1074
1075
1076
1077
1078 if (len != 0)
1079 xdr_set_page_base(xdr, 0, len);
1080}
1081EXPORT_SYMBOL_GPL(xdr_enter_page);
1082
1083static struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0};
1084
1085void
1086xdr_buf_from_iov(struct kvec *iov, struct xdr_buf *buf)
1087{
1088 buf->head[0] = *iov;
1089 buf->tail[0] = empty_iov;
1090 buf->page_len = 0;
1091 buf->buflen = buf->len = iov->iov_len;
1092}
1093EXPORT_SYMBOL_GPL(xdr_buf_from_iov);
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109int
1110xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
1111 unsigned int base, unsigned int len)
1112{
1113 subbuf->buflen = subbuf->len = len;
1114 if (base < buf->head[0].iov_len) {
1115 subbuf->head[0].iov_base = buf->head[0].iov_base + base;
1116 subbuf->head[0].iov_len = min_t(unsigned int, len,
1117 buf->head[0].iov_len - base);
1118 len -= subbuf->head[0].iov_len;
1119 base = 0;
1120 } else {
1121 base -= buf->head[0].iov_len;
1122 subbuf->head[0].iov_len = 0;
1123 }
1124
1125 if (base < buf->page_len) {
1126 subbuf->page_len = min(buf->page_len - base, len);
1127 base += buf->page_base;
1128 subbuf->page_base = base & ~PAGE_MASK;
1129 subbuf->pages = &buf->pages[base >> PAGE_SHIFT];
1130 len -= subbuf->page_len;
1131 base = 0;
1132 } else {
1133 base -= buf->page_len;
1134 subbuf->page_len = 0;
1135 }
1136
1137 if (base < buf->tail[0].iov_len) {
1138 subbuf->tail[0].iov_base = buf->tail[0].iov_base + base;
1139 subbuf->tail[0].iov_len = min_t(unsigned int, len,
1140 buf->tail[0].iov_len - base);
1141 len -= subbuf->tail[0].iov_len;
1142 base = 0;
1143 } else {
1144 base -= buf->tail[0].iov_len;
1145 subbuf->tail[0].iov_len = 0;
1146 }
1147
1148 if (base || len)
1149 return -1;
1150 return 0;
1151}
1152EXPORT_SYMBOL_GPL(xdr_buf_subsegment);
1153
1154static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
1155{
1156 unsigned int this_len;
1157
1158 this_len = min_t(unsigned int, len, subbuf->head[0].iov_len);
1159 memcpy(obj, subbuf->head[0].iov_base, this_len);
1160 len -= this_len;
1161 obj += this_len;
1162 this_len = min_t(unsigned int, len, subbuf->page_len);
1163 if (this_len)
1164 _copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len);
1165 len -= this_len;
1166 obj += this_len;
1167 this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
1168 memcpy(obj, subbuf->tail[0].iov_base, this_len);
1169}
1170
1171
1172int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
1173{
1174 struct xdr_buf subbuf;
1175 int status;
1176
1177 status = xdr_buf_subsegment(buf, &subbuf, base, len);
1178 if (status != 0)
1179 return status;
1180 __read_bytes_from_xdr_buf(&subbuf, obj, len);
1181 return 0;
1182}
1183EXPORT_SYMBOL_GPL(read_bytes_from_xdr_buf);
1184
1185static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
1186{
1187 unsigned int this_len;
1188
1189 this_len = min_t(unsigned int, len, subbuf->head[0].iov_len);
1190 memcpy(subbuf->head[0].iov_base, obj, this_len);
1191 len -= this_len;
1192 obj += this_len;
1193 this_len = min_t(unsigned int, len, subbuf->page_len);
1194 if (this_len)
1195 _copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len);
1196 len -= this_len;
1197 obj += this_len;
1198 this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
1199 memcpy(subbuf->tail[0].iov_base, obj, this_len);
1200}
1201
1202
1203int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
1204{
1205 struct xdr_buf subbuf;
1206 int status;
1207
1208 status = xdr_buf_subsegment(buf, &subbuf, base, len);
1209 if (status != 0)
1210 return status;
1211 __write_bytes_to_xdr_buf(&subbuf, obj, len);
1212 return 0;
1213}
1214EXPORT_SYMBOL_GPL(write_bytes_to_xdr_buf);
1215
1216int
1217xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj)
1218{
1219 __be32 raw;
1220 int status;
1221
1222 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj));
1223 if (status)
1224 return status;
1225 *obj = be32_to_cpu(raw);
1226 return 0;
1227}
1228EXPORT_SYMBOL_GPL(xdr_decode_word);
1229
1230int
1231xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj)
1232{
1233 __be32 raw = cpu_to_be32(obj);
1234
1235 return write_bytes_to_xdr_buf(buf, base, &raw, sizeof(obj));
1236}
1237EXPORT_SYMBOL_GPL(xdr_encode_word);
1238
1239
1240
1241
1242
1243int xdr_buf_read_netobj(struct xdr_buf *buf, struct xdr_netobj *obj, unsigned int offset)
1244{
1245 struct xdr_buf subbuf;
1246
1247 if (xdr_decode_word(buf, offset, &obj->len))
1248 return -EFAULT;
1249 if (xdr_buf_subsegment(buf, &subbuf, offset + 4, obj->len))
1250 return -EFAULT;
1251
1252
1253 obj->data = subbuf.head[0].iov_base;
1254 if (subbuf.head[0].iov_len == obj->len)
1255 return 0;
1256
1257 obj->data = subbuf.tail[0].iov_base;
1258 if (subbuf.tail[0].iov_len == obj->len)
1259 return 0;
1260
1261
1262
1263
1264
1265
1266 if (obj->len > buf->buflen - buf->len)
1267 return -ENOMEM;
1268 if (buf->tail[0].iov_len != 0)
1269 obj->data = buf->tail[0].iov_base + buf->tail[0].iov_len;
1270 else
1271 obj->data = buf->head[0].iov_base + buf->head[0].iov_len;
1272 __read_bytes_from_xdr_buf(&subbuf, obj->data, obj->len);
1273 return 0;
1274}
1275EXPORT_SYMBOL_GPL(xdr_buf_read_netobj);
1276
1277
1278static int
1279xdr_xcode_array2(struct xdr_buf *buf, unsigned int base,
1280 struct xdr_array2_desc *desc, int encode)
1281{
1282 char *elem = NULL, *c;
1283 unsigned int copied = 0, todo, avail_here;
1284 struct page **ppages = NULL;
1285 int err;
1286
1287 if (encode) {
1288 if (xdr_encode_word(buf, base, desc->array_len) != 0)
1289 return -EINVAL;
1290 } else {
1291 if (xdr_decode_word(buf, base, &desc->array_len) != 0 ||
1292 desc->array_len > desc->array_maxlen ||
1293 (unsigned long) base + 4 + desc->array_len *
1294 desc->elem_size > buf->len)
1295 return -EINVAL;
1296 }
1297 base += 4;
1298
1299 if (!desc->xcode)
1300 return 0;
1301
1302 todo = desc->array_len * desc->elem_size;
1303
1304
1305 if (todo && base < buf->head->iov_len) {
1306 c = buf->head->iov_base + base;
1307 avail_here = min_t(unsigned int, todo,
1308 buf->head->iov_len - base);
1309 todo -= avail_here;
1310
1311 while (avail_here >= desc->elem_size) {
1312 err = desc->xcode(desc, c);
1313 if (err)
1314 goto out;
1315 c += desc->elem_size;
1316 avail_here -= desc->elem_size;
1317 }
1318 if (avail_here) {
1319 if (!elem) {
1320 elem = kmalloc(desc->elem_size, GFP_KERNEL);
1321 err = -ENOMEM;
1322 if (!elem)
1323 goto out;
1324 }
1325 if (encode) {
1326 err = desc->xcode(desc, elem);
1327 if (err)
1328 goto out;
1329 memcpy(c, elem, avail_here);
1330 } else
1331 memcpy(elem, c, avail_here);
1332 copied = avail_here;
1333 }
1334 base = buf->head->iov_len;
1335 }
1336
1337
1338 base -= buf->head->iov_len;
1339 if (todo && base < buf->page_len) {
1340 unsigned int avail_page;
1341
1342 avail_here = min(todo, buf->page_len - base);
1343 todo -= avail_here;
1344
1345 base += buf->page_base;
1346 ppages = buf->pages + (base >> PAGE_SHIFT);
1347 base &= ~PAGE_MASK;
1348 avail_page = min_t(unsigned int, PAGE_SIZE - base,
1349 avail_here);
1350 c = kmap(*ppages) + base;
1351
1352 while (avail_here) {
1353 avail_here -= avail_page;
1354 if (copied || avail_page < desc->elem_size) {
1355 unsigned int l = min(avail_page,
1356 desc->elem_size - copied);
1357 if (!elem) {
1358 elem = kmalloc(desc->elem_size,
1359 GFP_KERNEL);
1360 err = -ENOMEM;
1361 if (!elem)
1362 goto out;
1363 }
1364 if (encode) {
1365 if (!copied) {
1366 err = desc->xcode(desc, elem);
1367 if (err)
1368 goto out;
1369 }
1370 memcpy(c, elem + copied, l);
1371 copied += l;
1372 if (copied == desc->elem_size)
1373 copied = 0;
1374 } else {
1375 memcpy(elem + copied, c, l);
1376 copied += l;
1377 if (copied == desc->elem_size) {
1378 err = desc->xcode(desc, elem);
1379 if (err)
1380 goto out;
1381 copied = 0;
1382 }
1383 }
1384 avail_page -= l;
1385 c += l;
1386 }
1387 while (avail_page >= desc->elem_size) {
1388 err = desc->xcode(desc, c);
1389 if (err)
1390 goto out;
1391 c += desc->elem_size;
1392 avail_page -= desc->elem_size;
1393 }
1394 if (avail_page) {
1395 unsigned int l = min(avail_page,
1396 desc->elem_size - copied);
1397 if (!elem) {
1398 elem = kmalloc(desc->elem_size,
1399 GFP_KERNEL);
1400 err = -ENOMEM;
1401 if (!elem)
1402 goto out;
1403 }
1404 if (encode) {
1405 if (!copied) {
1406 err = desc->xcode(desc, elem);
1407 if (err)
1408 goto out;
1409 }
1410 memcpy(c, elem + copied, l);
1411 copied += l;
1412 if (copied == desc->elem_size)
1413 copied = 0;
1414 } else {
1415 memcpy(elem + copied, c, l);
1416 copied += l;
1417 if (copied == desc->elem_size) {
1418 err = desc->xcode(desc, elem);
1419 if (err)
1420 goto out;
1421 copied = 0;
1422 }
1423 }
1424 }
1425 if (avail_here) {
1426 kunmap(*ppages);
1427 ppages++;
1428 c = kmap(*ppages);
1429 }
1430
1431 avail_page = min(avail_here,
1432 (unsigned int) PAGE_SIZE);
1433 }
1434 base = buf->page_len;
1435 }
1436
1437
1438 base -= buf->page_len;
1439 if (todo) {
1440 c = buf->tail->iov_base + base;
1441 if (copied) {
1442 unsigned int l = desc->elem_size - copied;
1443
1444 if (encode)
1445 memcpy(c, elem + copied, l);
1446 else {
1447 memcpy(elem + copied, c, l);
1448 err = desc->xcode(desc, elem);
1449 if (err)
1450 goto out;
1451 }
1452 todo -= l;
1453 c += l;
1454 }
1455 while (todo) {
1456 err = desc->xcode(desc, c);
1457 if (err)
1458 goto out;
1459 c += desc->elem_size;
1460 todo -= desc->elem_size;
1461 }
1462 }
1463 err = 0;
1464
1465out:
1466 kfree(elem);
1467 if (ppages)
1468 kunmap(*ppages);
1469 return err;
1470}
1471
1472int
1473xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
1474 struct xdr_array2_desc *desc)
1475{
1476 if (base >= buf->len)
1477 return -EINVAL;
1478
1479 return xdr_xcode_array2(buf, base, desc, 0);
1480}
1481EXPORT_SYMBOL_GPL(xdr_decode_array2);
1482
1483int
1484xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
1485 struct xdr_array2_desc *desc)
1486{
1487 if ((unsigned long) base + 4 + desc->array_len * desc->elem_size >
1488 buf->head->iov_len + buf->page_len + buf->tail->iov_len)
1489 return -EINVAL;
1490
1491 return xdr_xcode_array2(buf, base, desc, 1);
1492}
1493EXPORT_SYMBOL_GPL(xdr_encode_array2);
1494
1495int
1496xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len,
1497 int (*actor)(struct scatterlist *, void *), void *data)
1498{
1499 int i, ret = 0;
1500 unsigned int page_len, thislen, page_offset;
1501 struct scatterlist sg[1];
1502
1503 sg_init_table(sg, 1);
1504
1505 if (offset >= buf->head[0].iov_len) {
1506 offset -= buf->head[0].iov_len;
1507 } else {
1508 thislen = buf->head[0].iov_len - offset;
1509 if (thislen > len)
1510 thislen = len;
1511 sg_set_buf(sg, buf->head[0].iov_base + offset, thislen);
1512 ret = actor(sg, data);
1513 if (ret)
1514 goto out;
1515 offset = 0;
1516 len -= thislen;
1517 }
1518 if (len == 0)
1519 goto out;
1520
1521 if (offset >= buf->page_len) {
1522 offset -= buf->page_len;
1523 } else {
1524 page_len = buf->page_len - offset;
1525 if (page_len > len)
1526 page_len = len;
1527 len -= page_len;
1528 page_offset = (offset + buf->page_base) & (PAGE_SIZE - 1);
1529 i = (offset + buf->page_base) >> PAGE_SHIFT;
1530 thislen = PAGE_SIZE - page_offset;
1531 do {
1532 if (thislen > page_len)
1533 thislen = page_len;
1534 sg_set_page(sg, buf->pages[i], thislen, page_offset);
1535 ret = actor(sg, data);
1536 if (ret)
1537 goto out;
1538 page_len -= thislen;
1539 i++;
1540 page_offset = 0;
1541 thislen = PAGE_SIZE;
1542 } while (page_len != 0);
1543 offset = 0;
1544 }
1545 if (len == 0)
1546 goto out;
1547 if (offset < buf->tail[0].iov_len) {
1548 thislen = buf->tail[0].iov_len - offset;
1549 if (thislen > len)
1550 thislen = len;
1551 sg_set_buf(sg, buf->tail[0].iov_base + offset, thislen);
1552 ret = actor(sg, data);
1553 len -= thislen;
1554 }
1555 if (len != 0)
1556 ret = -EINVAL;
1557out:
1558 return ret;
1559}
1560EXPORT_SYMBOL_GPL(xdr_process_buf);
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, size_t size)
1574{
1575 ssize_t ret;
1576 void *p;
1577
1578 ret = xdr_stream_decode_opaque_inline(xdr, &p, size);
1579 if (ret <= 0)
1580 return ret;
1581 memcpy(ptr, p, ret);
1582 return ret;
1583}
1584EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque);
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr,
1600 size_t maxlen, gfp_t gfp_flags)
1601{
1602 ssize_t ret;
1603 void *p;
1604
1605 ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen);
1606 if (ret > 0) {
1607 *ptr = kmemdup(p, ret, gfp_flags);
1608 if (*ptr != NULL)
1609 return ret;
1610 ret = -ENOMEM;
1611 }
1612 *ptr = NULL;
1613 return ret;
1614}
1615EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque_dup);
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, size_t size)
1629{
1630 ssize_t ret;
1631 void *p;
1632
1633 ret = xdr_stream_decode_opaque_inline(xdr, &p, size);
1634 if (ret > 0) {
1635 memcpy(str, p, ret);
1636 str[ret] = '\0';
1637 return strlen(str);
1638 }
1639 *str = '\0';
1640 return ret;
1641}
1642EXPORT_SYMBOL_GPL(xdr_stream_decode_string);
1643
1644
1645
1646
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1656
1657ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
1658 size_t maxlen, gfp_t gfp_flags)
1659{
1660 void *p;
1661 ssize_t ret;
1662
1663 ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen);
1664 if (ret > 0) {
1665 char *s = kmalloc(ret + 1, gfp_flags);
1666 if (s != NULL) {
1667 memcpy(s, p, ret);
1668 s[ret] = '\0';
1669 *str = s;
1670 return strlen(s);
1671 }
1672 ret = -ENOMEM;
1673 }
1674 *str = NULL;
1675 return ret;
1676}
1677EXPORT_SYMBOL_GPL(xdr_stream_decode_string_dup);
1678