Commit | Line | Data |
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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/net/sunrpc/xdr.c | |
4 | * | |
5 | * Generic XDR support. | |
6 | * | |
7 | * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> | |
8 | */ | |
9 | ||
a246b010 | 10 | #include <linux/module.h> |
5a0e3ad6 | 11 | #include <linux/slab.h> |
1da177e4 | 12 | #include <linux/types.h> |
1da177e4 LT |
13 | #include <linux/string.h> |
14 | #include <linux/kernel.h> | |
15 | #include <linux/pagemap.h> | |
16 | #include <linux/errno.h> | |
1da177e4 LT |
17 | #include <linux/sunrpc/xdr.h> |
18 | #include <linux/sunrpc/msg_prot.h> | |
9d96acbc | 19 | #include <linux/bvec.h> |
5582863f | 20 | #include <trace/events/sunrpc.h> |
1da177e4 | 21 | |
e6ac0acc AS |
22 | static void _copy_to_pages(struct page **, size_t, const char *, size_t); |
23 | ||
24 | ||
1da177e4 LT |
25 | /* |
26 | * XDR functions for basic NFS types | |
27 | */ | |
d8ed029d AD |
28 | __be32 * |
29 | xdr_encode_netobj(__be32 *p, const struct xdr_netobj *obj) | |
1da177e4 LT |
30 | { |
31 | unsigned int quadlen = XDR_QUADLEN(obj->len); | |
32 | ||
33 | p[quadlen] = 0; /* zero trailing bytes */ | |
9f162d2a | 34 | *p++ = cpu_to_be32(obj->len); |
1da177e4 LT |
35 | memcpy(p, obj->data, obj->len); |
36 | return p + XDR_QUADLEN(obj->len); | |
37 | } | |
468039ee | 38 | EXPORT_SYMBOL_GPL(xdr_encode_netobj); |
1da177e4 | 39 | |
d8ed029d AD |
40 | __be32 * |
41 | xdr_decode_netobj(__be32 *p, struct xdr_netobj *obj) | |
1da177e4 LT |
42 | { |
43 | unsigned int len; | |
44 | ||
98866b5a | 45 | if ((len = be32_to_cpu(*p++)) > XDR_MAX_NETOBJ) |
1da177e4 LT |
46 | return NULL; |
47 | obj->len = len; | |
48 | obj->data = (u8 *) p; | |
49 | return p + XDR_QUADLEN(len); | |
50 | } | |
468039ee | 51 | EXPORT_SYMBOL_GPL(xdr_decode_netobj); |
1da177e4 LT |
52 | |
53 | /** | |
54 | * xdr_encode_opaque_fixed - Encode fixed length opaque data | |
4dc3b16b PP |
55 | * @p: pointer to current position in XDR buffer. |
56 | * @ptr: pointer to data to encode (or NULL) | |
57 | * @nbytes: size of data. | |
1da177e4 LT |
58 | * |
59 | * Copy the array of data of length nbytes at ptr to the XDR buffer | |
60 | * at position p, then align to the next 32-bit boundary by padding | |
61 | * with zero bytes (see RFC1832). | |
62 | * Note: if ptr is NULL, only the padding is performed. | |
63 | * | |
64 | * Returns the updated current XDR buffer position | |
65 | * | |
66 | */ | |
d8ed029d | 67 | __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int nbytes) |
1da177e4 LT |
68 | { |
69 | if (likely(nbytes != 0)) { | |
70 | unsigned int quadlen = XDR_QUADLEN(nbytes); | |
71 | unsigned int padding = (quadlen << 2) - nbytes; | |
72 | ||
73 | if (ptr != NULL) | |
74 | memcpy(p, ptr, nbytes); | |
75 | if (padding != 0) | |
76 | memset((char *)p + nbytes, 0, padding); | |
77 | p += quadlen; | |
78 | } | |
79 | return p; | |
80 | } | |
468039ee | 81 | EXPORT_SYMBOL_GPL(xdr_encode_opaque_fixed); |
1da177e4 LT |
82 | |
83 | /** | |
84 | * xdr_encode_opaque - Encode variable length opaque data | |
4dc3b16b PP |
85 | * @p: pointer to current position in XDR buffer. |
86 | * @ptr: pointer to data to encode (or NULL) | |
87 | * @nbytes: size of data. | |
1da177e4 LT |
88 | * |
89 | * Returns the updated current XDR buffer position | |
90 | */ | |
d8ed029d | 91 | __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int nbytes) |
1da177e4 | 92 | { |
9f162d2a | 93 | *p++ = cpu_to_be32(nbytes); |
1da177e4 LT |
94 | return xdr_encode_opaque_fixed(p, ptr, nbytes); |
95 | } | |
468039ee | 96 | EXPORT_SYMBOL_GPL(xdr_encode_opaque); |
1da177e4 | 97 | |
d8ed029d AD |
98 | __be32 * |
99 | xdr_encode_string(__be32 *p, const char *string) | |
1da177e4 LT |
100 | { |
101 | return xdr_encode_array(p, string, strlen(string)); | |
102 | } | |
468039ee | 103 | EXPORT_SYMBOL_GPL(xdr_encode_string); |
1da177e4 | 104 | |
d8ed029d | 105 | __be32 * |
e5cff482 CL |
106 | xdr_decode_string_inplace(__be32 *p, char **sp, |
107 | unsigned int *lenp, unsigned int maxlen) | |
1da177e4 | 108 | { |
e5cff482 | 109 | u32 len; |
1da177e4 | 110 | |
98866b5a | 111 | len = be32_to_cpu(*p++); |
e5cff482 | 112 | if (len > maxlen) |
1da177e4 LT |
113 | return NULL; |
114 | *lenp = len; | |
115 | *sp = (char *) p; | |
116 | return p + XDR_QUADLEN(len); | |
117 | } | |
468039ee | 118 | EXPORT_SYMBOL_GPL(xdr_decode_string_inplace); |
1da177e4 | 119 | |
b4687da7 CL |
120 | /** |
121 | * xdr_terminate_string - '\0'-terminate a string residing in an xdr_buf | |
122 | * @buf: XDR buffer where string resides | |
123 | * @len: length of string, in bytes | |
124 | * | |
125 | */ | |
f8d0e60f | 126 | void xdr_terminate_string(const struct xdr_buf *buf, const u32 len) |
b4687da7 CL |
127 | { |
128 | char *kaddr; | |
129 | ||
b8541786 | 130 | kaddr = kmap_atomic(buf->pages[0]); |
b4687da7 | 131 | kaddr[buf->page_base + len] = '\0'; |
b8541786 | 132 | kunmap_atomic(kaddr); |
b4687da7 | 133 | } |
0d961aa9 | 134 | EXPORT_SYMBOL_GPL(xdr_terminate_string); |
b4687da7 | 135 | |
f8d0e60f | 136 | size_t xdr_buf_pagecount(const struct xdr_buf *buf) |
9d96acbc TM |
137 | { |
138 | if (!buf->page_len) | |
139 | return 0; | |
140 | return (buf->page_base + buf->page_len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
141 | } | |
142 | ||
143 | int | |
144 | xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp) | |
145 | { | |
146 | size_t i, n = xdr_buf_pagecount(buf); | |
147 | ||
148 | if (n != 0 && buf->bvec == NULL) { | |
149 | buf->bvec = kmalloc_array(n, sizeof(buf->bvec[0]), gfp); | |
150 | if (!buf->bvec) | |
151 | return -ENOMEM; | |
152 | for (i = 0; i < n; i++) { | |
9088151f CH |
153 | bvec_set_page(&buf->bvec[i], buf->pages[i], PAGE_SIZE, |
154 | 0); | |
9d96acbc TM |
155 | } |
156 | } | |
157 | return 0; | |
158 | } | |
159 | ||
160 | void | |
161 | xdr_free_bvec(struct xdr_buf *buf) | |
162 | { | |
163 | kfree(buf->bvec); | |
164 | buf->bvec = NULL; | |
165 | } | |
166 | ||
cf500bac CL |
167 | /** |
168 | * xdr_inline_pages - Prepare receive buffer for a large reply | |
169 | * @xdr: xdr_buf into which reply will be placed | |
170 | * @offset: expected offset where data payload will start, in bytes | |
171 | * @pages: vector of struct page pointers | |
172 | * @base: offset in first page where receive should start, in bytes | |
173 | * @len: expected size of the upper layer data payload, in bytes | |
174 | * | |
175 | */ | |
1da177e4 LT |
176 | void |
177 | xdr_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; | |
1da177e4 LT |
193 | xdr->buflen += len; |
194 | } | |
468039ee | 195 | EXPORT_SYMBOL_GPL(xdr_inline_pages); |
1da177e4 | 196 | |
1da177e4 LT |
197 | /* |
198 | * Helper routines for doing 'memmove' like operations on a struct xdr_buf | |
2c53040f BH |
199 | */ |
200 | ||
e6ac0acc AS |
201 | /** |
202 | * _shift_data_left_pages | |
203 | * @pages: vector of pages containing both the source and dest memory area. | |
204 | * @pgto_base: page vector address of destination | |
205 | * @pgfrom_base: page vector address of source | |
206 | * @len: number of bytes to copy | |
207 | * | |
208 | * Note: the addresses pgto_base and pgfrom_base are both calculated in | |
209 | * the same way: | |
210 | * if a memory area starts at byte 'base' in page 'pages[i]', | |
211 | * then its address is given as (i << PAGE_CACHE_SHIFT) + base | |
212 | * Alse note: pgto_base must be < pgfrom_base, but the memory areas | |
213 | * they point to may overlap. | |
214 | */ | |
215 | static void | |
216 | _shift_data_left_pages(struct page **pages, size_t pgto_base, | |
217 | size_t pgfrom_base, size_t len) | |
218 | { | |
219 | struct page **pgfrom, **pgto; | |
220 | char *vfrom, *vto; | |
221 | size_t copy; | |
222 | ||
223 | BUG_ON(pgfrom_base <= pgto_base); | |
224 | ||
c54e959b TM |
225 | if (!len) |
226 | return; | |
227 | ||
e6ac0acc AS |
228 | pgto = pages + (pgto_base >> PAGE_SHIFT); |
229 | pgfrom = pages + (pgfrom_base >> PAGE_SHIFT); | |
230 | ||
231 | pgto_base &= ~PAGE_MASK; | |
232 | pgfrom_base &= ~PAGE_MASK; | |
233 | ||
234 | do { | |
235 | if (pgto_base >= PAGE_SIZE) { | |
236 | pgto_base = 0; | |
237 | pgto++; | |
238 | } | |
239 | if (pgfrom_base >= PAGE_SIZE){ | |
240 | pgfrom_base = 0; | |
241 | pgfrom++; | |
242 | } | |
243 | ||
244 | copy = len; | |
245 | if (copy > (PAGE_SIZE - pgto_base)) | |
246 | copy = PAGE_SIZE - pgto_base; | |
247 | if (copy > (PAGE_SIZE - pgfrom_base)) | |
248 | copy = PAGE_SIZE - pgfrom_base; | |
249 | ||
250 | vto = kmap_atomic(*pgto); | |
251 | if (*pgto != *pgfrom) { | |
252 | vfrom = kmap_atomic(*pgfrom); | |
253 | memcpy(vto + pgto_base, vfrom + pgfrom_base, copy); | |
254 | kunmap_atomic(vfrom); | |
255 | } else | |
256 | memmove(vto + pgto_base, vto + pgfrom_base, copy); | |
257 | flush_dcache_page(*pgto); | |
258 | kunmap_atomic(vto); | |
259 | ||
260 | pgto_base += copy; | |
261 | pgfrom_base += copy; | |
262 | ||
263 | } while ((len -= copy) != 0); | |
264 | } | |
265 | ||
2c53040f | 266 | /** |
1da177e4 LT |
267 | * _shift_data_right_pages |
268 | * @pages: vector of pages containing both the source and dest memory area. | |
269 | * @pgto_base: page vector address of destination | |
270 | * @pgfrom_base: page vector address of source | |
271 | * @len: number of bytes to copy | |
272 | * | |
273 | * Note: the addresses pgto_base and pgfrom_base are both calculated in | |
274 | * the same way: | |
275 | * if a memory area starts at byte 'base' in page 'pages[i]', | |
ea1754a0 | 276 | * then its address is given as (i << PAGE_SHIFT) + base |
1da177e4 LT |
277 | * Also note: pgfrom_base must be < pgto_base, but the memory areas |
278 | * they point to may overlap. | |
279 | */ | |
280 | static void | |
281 | _shift_data_right_pages(struct page **pages, size_t pgto_base, | |
282 | size_t pgfrom_base, size_t len) | |
283 | { | |
284 | struct page **pgfrom, **pgto; | |
285 | char *vfrom, *vto; | |
286 | size_t copy; | |
287 | ||
288 | BUG_ON(pgto_base <= pgfrom_base); | |
289 | ||
c54e959b TM |
290 | if (!len) |
291 | return; | |
292 | ||
1da177e4 LT |
293 | pgto_base += len; |
294 | pgfrom_base += len; | |
295 | ||
09cbfeaf KS |
296 | pgto = pages + (pgto_base >> PAGE_SHIFT); |
297 | pgfrom = pages + (pgfrom_base >> PAGE_SHIFT); | |
1da177e4 | 298 | |
09cbfeaf KS |
299 | pgto_base &= ~PAGE_MASK; |
300 | pgfrom_base &= ~PAGE_MASK; | |
1da177e4 LT |
301 | |
302 | do { | |
303 | /* Are any pointers crossing a page boundary? */ | |
304 | if (pgto_base == 0) { | |
09cbfeaf | 305 | pgto_base = PAGE_SIZE; |
1da177e4 LT |
306 | pgto--; |
307 | } | |
308 | if (pgfrom_base == 0) { | |
09cbfeaf | 309 | pgfrom_base = PAGE_SIZE; |
1da177e4 LT |
310 | pgfrom--; |
311 | } | |
312 | ||
313 | copy = len; | |
314 | if (copy > pgto_base) | |
315 | copy = pgto_base; | |
316 | if (copy > pgfrom_base) | |
317 | copy = pgfrom_base; | |
318 | pgto_base -= copy; | |
319 | pgfrom_base -= copy; | |
320 | ||
b8541786 | 321 | vto = kmap_atomic(*pgto); |
347e2233 TM |
322 | if (*pgto != *pgfrom) { |
323 | vfrom = kmap_atomic(*pgfrom); | |
324 | memcpy(vto + pgto_base, vfrom + pgfrom_base, copy); | |
325 | kunmap_atomic(vfrom); | |
326 | } else | |
327 | memmove(vto + pgto_base, vto + pgfrom_base, copy); | |
bce3481c | 328 | flush_dcache_page(*pgto); |
b8541786 | 329 | kunmap_atomic(vto); |
1da177e4 LT |
330 | |
331 | } while ((len -= copy) != 0); | |
1da177e4 LT |
332 | } |
333 | ||
2c53040f | 334 | /** |
1da177e4 LT |
335 | * _copy_to_pages |
336 | * @pages: array of pages | |
337 | * @pgbase: page vector address of destination | |
338 | * @p: pointer to source data | |
339 | * @len: length | |
340 | * | |
341 | * Copies data from an arbitrary memory location into an array of pages | |
342 | * The copy is assumed to be non-overlapping. | |
343 | */ | |
344 | static void | |
345 | _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len) | |
346 | { | |
347 | struct page **pgto; | |
348 | char *vto; | |
349 | size_t copy; | |
350 | ||
c54e959b TM |
351 | if (!len) |
352 | return; | |
353 | ||
09cbfeaf KS |
354 | pgto = pages + (pgbase >> PAGE_SHIFT); |
355 | pgbase &= ~PAGE_MASK; | |
1da177e4 | 356 | |
daeba89d | 357 | for (;;) { |
09cbfeaf | 358 | copy = PAGE_SIZE - pgbase; |
1da177e4 LT |
359 | if (copy > len) |
360 | copy = len; | |
361 | ||
b8541786 | 362 | vto = kmap_atomic(*pgto); |
1da177e4 | 363 | memcpy(vto + pgbase, p, copy); |
b8541786 | 364 | kunmap_atomic(vto); |
1da177e4 | 365 | |
daeba89d TM |
366 | len -= copy; |
367 | if (len == 0) | |
368 | break; | |
369 | ||
1da177e4 | 370 | pgbase += copy; |
09cbfeaf | 371 | if (pgbase == PAGE_SIZE) { |
1da177e4 LT |
372 | flush_dcache_page(*pgto); |
373 | pgbase = 0; | |
374 | pgto++; | |
375 | } | |
376 | p += copy; | |
daeba89d | 377 | } |
1da177e4 LT |
378 | flush_dcache_page(*pgto); |
379 | } | |
380 | ||
2c53040f | 381 | /** |
1da177e4 LT |
382 | * _copy_from_pages |
383 | * @p: pointer to destination | |
384 | * @pages: array of pages | |
385 | * @pgbase: offset of source data | |
386 | * @len: length | |
387 | * | |
388 | * Copies data into an arbitrary memory location from an array of pages | |
389 | * The copy is assumed to be non-overlapping. | |
390 | */ | |
bf118a34 | 391 | void |
1da177e4 LT |
392 | _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len) |
393 | { | |
394 | struct page **pgfrom; | |
395 | char *vfrom; | |
396 | size_t copy; | |
397 | ||
c54e959b TM |
398 | if (!len) |
399 | return; | |
400 | ||
09cbfeaf KS |
401 | pgfrom = pages + (pgbase >> PAGE_SHIFT); |
402 | pgbase &= ~PAGE_MASK; | |
1da177e4 LT |
403 | |
404 | do { | |
09cbfeaf | 405 | copy = PAGE_SIZE - pgbase; |
1da177e4 LT |
406 | if (copy > len) |
407 | copy = len; | |
408 | ||
b8541786 | 409 | vfrom = kmap_atomic(*pgfrom); |
1da177e4 | 410 | memcpy(p, vfrom + pgbase, copy); |
b8541786 | 411 | kunmap_atomic(vfrom); |
1da177e4 LT |
412 | |
413 | pgbase += copy; | |
09cbfeaf | 414 | if (pgbase == PAGE_SIZE) { |
1da177e4 LT |
415 | pgbase = 0; |
416 | pgfrom++; | |
417 | } | |
418 | p += copy; | |
419 | ||
420 | } while ((len -= copy) != 0); | |
421 | } | |
bf118a34 | 422 | EXPORT_SYMBOL_GPL(_copy_from_pages); |
1da177e4 | 423 | |
c4f2f591 TM |
424 | static void xdr_buf_iov_zero(const struct kvec *iov, unsigned int base, |
425 | unsigned int len) | |
426 | { | |
427 | if (base >= iov->iov_len) | |
428 | return; | |
429 | if (len > iov->iov_len - base) | |
430 | len = iov->iov_len - base; | |
431 | memset(iov->iov_base + base, 0, len); | |
432 | } | |
433 | ||
84ce182a | 434 | /** |
c4f2f591 TM |
435 | * xdr_buf_pages_zero |
436 | * @buf: xdr_buf | |
437 | * @pgbase: beginning offset | |
84ce182a AS |
438 | * @len: length |
439 | */ | |
c4f2f591 TM |
440 | static void xdr_buf_pages_zero(const struct xdr_buf *buf, unsigned int pgbase, |
441 | unsigned int len) | |
84ce182a | 442 | { |
c4f2f591 | 443 | struct page **pages = buf->pages; |
84ce182a AS |
444 | struct page **page; |
445 | char *vpage; | |
c4f2f591 TM |
446 | unsigned int zero; |
447 | ||
448 | if (!len) | |
449 | return; | |
450 | if (pgbase >= buf->page_len) { | |
451 | xdr_buf_iov_zero(buf->tail, pgbase - buf->page_len, len); | |
452 | return; | |
453 | } | |
454 | if (pgbase + len > buf->page_len) { | |
455 | xdr_buf_iov_zero(buf->tail, 0, pgbase + len - buf->page_len); | |
456 | len = buf->page_len - pgbase; | |
457 | } | |
458 | ||
459 | pgbase += buf->page_base; | |
84ce182a AS |
460 | |
461 | page = pages + (pgbase >> PAGE_SHIFT); | |
462 | pgbase &= ~PAGE_MASK; | |
463 | ||
464 | do { | |
465 | zero = PAGE_SIZE - pgbase; | |
466 | if (zero > len) | |
467 | zero = len; | |
468 | ||
469 | vpage = kmap_atomic(*page); | |
470 | memset(vpage + pgbase, 0, zero); | |
471 | kunmap_atomic(vpage); | |
472 | ||
473 | flush_dcache_page(*page); | |
474 | pgbase = 0; | |
475 | page++; | |
476 | ||
477 | } while ((len -= zero) != 0); | |
478 | } | |
479 | ||
5802f7c2 TM |
480 | static unsigned int xdr_buf_pages_fill_sparse(const struct xdr_buf *buf, |
481 | unsigned int buflen, gfp_t gfp) | |
482 | { | |
483 | unsigned int i, npages, pagelen; | |
484 | ||
485 | if (!(buf->flags & XDRBUF_SPARSE_PAGES)) | |
486 | return buflen; | |
487 | if (buflen <= buf->head->iov_len) | |
488 | return buflen; | |
489 | pagelen = buflen - buf->head->iov_len; | |
490 | if (pagelen > buf->page_len) | |
491 | pagelen = buf->page_len; | |
492 | npages = (pagelen + buf->page_base + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
493 | for (i = 0; i < npages; i++) { | |
494 | if (!buf->pages[i]) | |
495 | continue; | |
496 | buf->pages[i] = alloc_page(gfp); | |
497 | if (likely(buf->pages[i])) | |
498 | continue; | |
499 | buflen -= pagelen; | |
500 | pagelen = i << PAGE_SHIFT; | |
501 | if (pagelen > buf->page_base) | |
502 | buflen += pagelen - buf->page_base; | |
503 | break; | |
504 | } | |
505 | return buflen; | |
506 | } | |
507 | ||
c4f2f591 TM |
508 | static void xdr_buf_try_expand(struct xdr_buf *buf, unsigned int len) |
509 | { | |
510 | struct kvec *head = buf->head; | |
511 | struct kvec *tail = buf->tail; | |
512 | unsigned int sum = head->iov_len + buf->page_len + tail->iov_len; | |
5802f7c2 | 513 | unsigned int free_space, newlen; |
c4f2f591 TM |
514 | |
515 | if (sum > buf->len) { | |
516 | free_space = min_t(unsigned int, sum - buf->len, len); | |
5802f7c2 TM |
517 | newlen = xdr_buf_pages_fill_sparse(buf, buf->len + free_space, |
518 | GFP_KERNEL); | |
519 | free_space = newlen - buf->len; | |
520 | buf->len = newlen; | |
c4f2f591 TM |
521 | len -= free_space; |
522 | if (!len) | |
523 | return; | |
524 | } | |
525 | ||
526 | if (buf->buflen > sum) { | |
527 | /* Expand the tail buffer */ | |
528 | free_space = min_t(unsigned int, buf->buflen - sum, len); | |
529 | tail->iov_len += free_space; | |
530 | buf->len += free_space; | |
531 | } | |
532 | } | |
533 | ||
534 | static void xdr_buf_tail_copy_right(const struct xdr_buf *buf, | |
535 | unsigned int base, unsigned int len, | |
536 | unsigned int shift) | |
537 | { | |
538 | const struct kvec *tail = buf->tail; | |
539 | unsigned int to = base + shift; | |
540 | ||
541 | if (to >= tail->iov_len) | |
542 | return; | |
543 | if (len + to > tail->iov_len) | |
544 | len = tail->iov_len - to; | |
545 | memmove(tail->iov_base + to, tail->iov_base + base, len); | |
546 | } | |
547 | ||
548 | static void xdr_buf_pages_copy_right(const struct xdr_buf *buf, | |
549 | unsigned int base, unsigned int len, | |
550 | unsigned int shift) | |
551 | { | |
552 | const struct kvec *tail = buf->tail; | |
553 | unsigned int to = base + shift; | |
554 | unsigned int pglen = 0; | |
555 | unsigned int talen = 0, tato = 0; | |
556 | ||
557 | if (base >= buf->page_len) | |
558 | return; | |
559 | if (len > buf->page_len - base) | |
560 | len = buf->page_len - base; | |
561 | if (to >= buf->page_len) { | |
562 | tato = to - buf->page_len; | |
563 | if (tail->iov_len >= len + tato) | |
564 | talen = len; | |
565 | else if (tail->iov_len > tato) | |
566 | talen = tail->iov_len - tato; | |
567 | } else if (len + to >= buf->page_len) { | |
568 | pglen = buf->page_len - to; | |
569 | talen = len - pglen; | |
570 | if (talen > tail->iov_len) | |
571 | talen = tail->iov_len; | |
572 | } else | |
573 | pglen = len; | |
574 | ||
575 | _copy_from_pages(tail->iov_base + tato, buf->pages, | |
576 | buf->page_base + base + pglen, talen); | |
577 | _shift_data_right_pages(buf->pages, buf->page_base + to, | |
578 | buf->page_base + base, pglen); | |
579 | } | |
580 | ||
6707fbd7 TM |
581 | static void xdr_buf_head_copy_right(const struct xdr_buf *buf, |
582 | unsigned int base, unsigned int len, | |
583 | unsigned int shift) | |
584 | { | |
585 | const struct kvec *head = buf->head; | |
586 | const struct kvec *tail = buf->tail; | |
587 | unsigned int to = base + shift; | |
588 | unsigned int pglen = 0, pgto = 0; | |
589 | unsigned int talen = 0, tato = 0; | |
590 | ||
591 | if (base >= head->iov_len) | |
592 | return; | |
593 | if (len > head->iov_len - base) | |
594 | len = head->iov_len - base; | |
595 | if (to >= buf->page_len + head->iov_len) { | |
596 | tato = to - buf->page_len - head->iov_len; | |
597 | talen = len; | |
598 | } else if (to >= head->iov_len) { | |
599 | pgto = to - head->iov_len; | |
600 | pglen = len; | |
601 | if (pgto + pglen > buf->page_len) { | |
602 | talen = pgto + pglen - buf->page_len; | |
603 | pglen -= talen; | |
604 | } | |
605 | } else { | |
606 | pglen = len - to; | |
607 | if (pglen > buf->page_len) { | |
608 | talen = pglen - buf->page_len; | |
609 | pglen = buf->page_len; | |
610 | } | |
611 | } | |
612 | ||
613 | len -= talen; | |
614 | base += len; | |
615 | if (talen + tato > tail->iov_len) | |
616 | talen = tail->iov_len > tato ? tail->iov_len - tato : 0; | |
617 | memcpy(tail->iov_base + tato, head->iov_base + base, talen); | |
618 | ||
619 | len -= pglen; | |
620 | base -= pglen; | |
621 | _copy_to_pages(buf->pages, buf->page_base + pgto, head->iov_base + base, | |
622 | pglen); | |
623 | ||
624 | base -= len; | |
625 | memmove(head->iov_base + to, head->iov_base + base, len); | |
626 | } | |
627 | ||
c4f2f591 TM |
628 | static void xdr_buf_tail_shift_right(const struct xdr_buf *buf, |
629 | unsigned int base, unsigned int len, | |
630 | unsigned int shift) | |
631 | { | |
632 | const struct kvec *tail = buf->tail; | |
633 | ||
634 | if (base >= tail->iov_len || !shift || !len) | |
635 | return; | |
636 | xdr_buf_tail_copy_right(buf, base, len, shift); | |
637 | } | |
638 | ||
639 | static void xdr_buf_pages_shift_right(const struct xdr_buf *buf, | |
640 | unsigned int base, unsigned int len, | |
641 | unsigned int shift) | |
642 | { | |
643 | if (!shift || !len) | |
644 | return; | |
645 | if (base >= buf->page_len) { | |
646 | xdr_buf_tail_shift_right(buf, base - buf->page_len, len, shift); | |
647 | return; | |
648 | } | |
649 | if (base + len > buf->page_len) | |
650 | xdr_buf_tail_shift_right(buf, 0, base + len - buf->page_len, | |
651 | shift); | |
652 | xdr_buf_pages_copy_right(buf, base, len, shift); | |
653 | } | |
654 | ||
6707fbd7 TM |
655 | static void xdr_buf_head_shift_right(const struct xdr_buf *buf, |
656 | unsigned int base, unsigned int len, | |
657 | unsigned int shift) | |
658 | { | |
659 | const struct kvec *head = buf->head; | |
660 | ||
661 | if (!shift) | |
662 | return; | |
663 | if (base >= head->iov_len) { | |
664 | xdr_buf_pages_shift_right(buf, head->iov_len - base, len, | |
665 | shift); | |
666 | return; | |
667 | } | |
668 | if (base + len > head->iov_len) | |
669 | xdr_buf_pages_shift_right(buf, 0, base + len - head->iov_len, | |
670 | shift); | |
671 | xdr_buf_head_copy_right(buf, base, len, shift); | |
672 | } | |
673 | ||
9a20f6f4 TM |
674 | static void xdr_buf_tail_copy_left(const struct xdr_buf *buf, unsigned int base, |
675 | unsigned int len, unsigned int shift) | |
676 | { | |
677 | const struct kvec *tail = buf->tail; | |
678 | ||
679 | if (base >= tail->iov_len) | |
680 | return; | |
681 | if (len > tail->iov_len - base) | |
682 | len = tail->iov_len - base; | |
683 | /* Shift data into head */ | |
684 | if (shift > buf->page_len + base) { | |
685 | const struct kvec *head = buf->head; | |
686 | unsigned int hdto = | |
687 | head->iov_len + buf->page_len + base - shift; | |
688 | unsigned int hdlen = len; | |
689 | ||
690 | if (WARN_ONCE(shift > head->iov_len + buf->page_len + base, | |
691 | "SUNRPC: Misaligned data.\n")) | |
692 | return; | |
693 | if (hdto + hdlen > head->iov_len) | |
694 | hdlen = head->iov_len - hdto; | |
695 | memcpy(head->iov_base + hdto, tail->iov_base + base, hdlen); | |
696 | base += hdlen; | |
697 | len -= hdlen; | |
698 | if (!len) | |
699 | return; | |
700 | } | |
701 | /* Shift data into pages */ | |
702 | if (shift > base) { | |
703 | unsigned int pgto = buf->page_len + base - shift; | |
704 | unsigned int pglen = len; | |
705 | ||
706 | if (pgto + pglen > buf->page_len) | |
707 | pglen = buf->page_len - pgto; | |
708 | _copy_to_pages(buf->pages, buf->page_base + pgto, | |
709 | tail->iov_base + base, pglen); | |
710 | base += pglen; | |
711 | len -= pglen; | |
712 | if (!len) | |
713 | return; | |
714 | } | |
715 | memmove(tail->iov_base + base - shift, tail->iov_base + base, len); | |
716 | } | |
717 | ||
718 | static void xdr_buf_pages_copy_left(const struct xdr_buf *buf, | |
719 | unsigned int base, unsigned int len, | |
720 | unsigned int shift) | |
721 | { | |
722 | unsigned int pgto; | |
723 | ||
724 | if (base >= buf->page_len) | |
725 | return; | |
726 | if (len > buf->page_len - base) | |
727 | len = buf->page_len - base; | |
728 | /* Shift data into head */ | |
729 | if (shift > base) { | |
730 | const struct kvec *head = buf->head; | |
731 | unsigned int hdto = head->iov_len + base - shift; | |
732 | unsigned int hdlen = len; | |
733 | ||
734 | if (WARN_ONCE(shift > head->iov_len + base, | |
735 | "SUNRPC: Misaligned data.\n")) | |
736 | return; | |
737 | if (hdto + hdlen > head->iov_len) | |
738 | hdlen = head->iov_len - hdto; | |
739 | _copy_from_pages(head->iov_base + hdto, buf->pages, | |
740 | buf->page_base + base, hdlen); | |
741 | base += hdlen; | |
742 | len -= hdlen; | |
743 | if (!len) | |
744 | return; | |
745 | } | |
746 | pgto = base - shift; | |
747 | _shift_data_left_pages(buf->pages, buf->page_base + pgto, | |
748 | buf->page_base + base, len); | |
749 | } | |
750 | ||
751 | static void xdr_buf_tail_shift_left(const struct xdr_buf *buf, | |
752 | unsigned int base, unsigned int len, | |
753 | unsigned int shift) | |
754 | { | |
755 | if (!shift || !len) | |
756 | return; | |
757 | xdr_buf_tail_copy_left(buf, base, len, shift); | |
758 | } | |
759 | ||
760 | static void xdr_buf_pages_shift_left(const struct xdr_buf *buf, | |
761 | unsigned int base, unsigned int len, | |
762 | unsigned int shift) | |
763 | { | |
764 | if (!shift || !len) | |
765 | return; | |
766 | if (base >= buf->page_len) { | |
767 | xdr_buf_tail_shift_left(buf, base - buf->page_len, len, shift); | |
768 | return; | |
769 | } | |
770 | xdr_buf_pages_copy_left(buf, base, len, shift); | |
771 | len += base; | |
772 | if (len <= buf->page_len) | |
773 | return; | |
774 | xdr_buf_tail_copy_left(buf, 0, len - buf->page_len, shift); | |
775 | } | |
776 | ||
4f5f3b60 AS |
777 | static void xdr_buf_head_shift_left(const struct xdr_buf *buf, |
778 | unsigned int base, unsigned int len, | |
779 | unsigned int shift) | |
780 | { | |
781 | const struct kvec *head = buf->head; | |
782 | unsigned int bytes; | |
783 | ||
784 | if (!shift || !len) | |
785 | return; | |
786 | ||
787 | if (shift > base) { | |
788 | bytes = (shift - base); | |
789 | if (bytes >= len) | |
790 | return; | |
791 | base += bytes; | |
792 | len -= bytes; | |
793 | } | |
794 | ||
795 | if (base < head->iov_len) { | |
796 | bytes = min_t(unsigned int, len, head->iov_len - base); | |
797 | memmove(head->iov_base + (base - shift), | |
798 | head->iov_base + base, bytes); | |
799 | base += bytes; | |
800 | len -= bytes; | |
801 | } | |
802 | xdr_buf_pages_shift_left(buf, base - head->iov_len, len, shift); | |
803 | } | |
804 | ||
2c53040f | 805 | /** |
1da177e4 LT |
806 | * xdr_shrink_bufhead |
807 | * @buf: xdr_buf | |
6707fbd7 | 808 | * @len: new length of buf->head[0] |
1da177e4 | 809 | * |
6707fbd7 | 810 | * Shrinks XDR buffer's header kvec buf->head[0], setting it to |
1da177e4 LT |
811 | * 'len' bytes. The extra data is not lost, but is instead |
812 | * moved into the inlined pages and/or the tail. | |
813 | */ | |
6707fbd7 | 814 | static unsigned int xdr_shrink_bufhead(struct xdr_buf *buf, unsigned int len) |
1da177e4 | 815 | { |
6707fbd7 TM |
816 | struct kvec *head = buf->head; |
817 | unsigned int shift, buflen = max(buf->len, len); | |
18e624ad WAA |
818 | |
819 | WARN_ON_ONCE(len > head->iov_len); | |
6707fbd7 TM |
820 | if (head->iov_len > buflen) { |
821 | buf->buflen -= head->iov_len - buflen; | |
822 | head->iov_len = buflen; | |
1da177e4 | 823 | } |
6707fbd7 TM |
824 | if (len >= head->iov_len) |
825 | return 0; | |
826 | shift = head->iov_len - len; | |
827 | xdr_buf_try_expand(buf, shift); | |
828 | xdr_buf_head_shift_right(buf, len, buflen - len, shift); | |
829 | head->iov_len = len; | |
830 | buf->buflen -= shift; | |
831 | buf->len -= shift; | |
832 | return shift; | |
1da177e4 LT |
833 | } |
834 | ||
2c53040f | 835 | /** |
c4f2f591 | 836 | * xdr_shrink_pagelen - shrinks buf->pages to @len bytes |
1da177e4 | 837 | * @buf: xdr_buf |
c4f2f591 | 838 | * @len: new page buffer length |
1da177e4 | 839 | * |
e8d70b32 CL |
840 | * The extra data is not lost, but is instead moved into buf->tail. |
841 | * Returns the actual number of bytes moved. | |
1da177e4 | 842 | */ |
c4f2f591 | 843 | static unsigned int xdr_shrink_pagelen(struct xdr_buf *buf, unsigned int len) |
1da177e4 | 844 | { |
c4f2f591 | 845 | unsigned int shift, buflen = buf->len - buf->head->iov_len; |
1da177e4 | 846 | |
c4f2f591 TM |
847 | WARN_ON_ONCE(len > buf->page_len); |
848 | if (buf->head->iov_len >= buf->len || len > buflen) | |
849 | buflen = len; | |
850 | if (buf->page_len > buflen) { | |
851 | buf->buflen -= buf->page_len - buflen; | |
852 | buf->page_len = buflen; | |
853 | } | |
854 | if (len >= buf->page_len) | |
855 | return 0; | |
856 | shift = buf->page_len - len; | |
857 | xdr_buf_try_expand(buf, shift); | |
858 | xdr_buf_pages_shift_right(buf, len, buflen - len, shift); | |
859 | buf->page_len = len; | |
860 | buf->len -= shift; | |
861 | buf->buflen -= shift; | |
862 | return shift; | |
1da177e4 LT |
863 | } |
864 | ||
4517d526 TM |
865 | /** |
866 | * xdr_stream_pos - Return the current offset from the start of the xdr_stream | |
867 | * @xdr: pointer to struct xdr_stream | |
868 | */ | |
869 | unsigned int xdr_stream_pos(const struct xdr_stream *xdr) | |
870 | { | |
871 | return (unsigned int)(XDR_QUADLEN(xdr->buf->len) - xdr->nwords) << 2; | |
872 | } | |
873 | EXPORT_SYMBOL_GPL(xdr_stream_pos); | |
874 | ||
c4f2f591 TM |
875 | static void xdr_stream_set_pos(struct xdr_stream *xdr, unsigned int pos) |
876 | { | |
877 | unsigned int blen = xdr->buf->len; | |
878 | ||
879 | xdr->nwords = blen > pos ? XDR_QUADLEN(blen) - XDR_QUADLEN(pos) : 0; | |
880 | } | |
881 | ||
882 | static void xdr_stream_page_set_pos(struct xdr_stream *xdr, unsigned int pos) | |
883 | { | |
884 | xdr_stream_set_pos(xdr, pos + xdr->buf->head[0].iov_len); | |
885 | } | |
886 | ||
cf1f08ca AS |
887 | /** |
888 | * xdr_page_pos - Return the current offset from the start of the xdr pages | |
889 | * @xdr: pointer to struct xdr_stream | |
890 | */ | |
891 | unsigned int xdr_page_pos(const struct xdr_stream *xdr) | |
892 | { | |
893 | unsigned int pos = xdr_stream_pos(xdr); | |
894 | ||
895 | WARN_ON(pos < xdr->buf->head[0].iov_len); | |
896 | return pos - xdr->buf->head[0].iov_len; | |
897 | } | |
898 | EXPORT_SYMBOL_GPL(xdr_page_pos); | |
899 | ||
1da177e4 LT |
900 | /** |
901 | * xdr_init_encode - Initialize a struct xdr_stream for sending data. | |
902 | * @xdr: pointer to xdr_stream struct | |
903 | * @buf: pointer to XDR buffer in which to encode data | |
904 | * @p: current pointer inside XDR buffer | |
0ccc61b1 | 905 | * @rqst: pointer to controlling rpc_rqst, for debugging |
1da177e4 LT |
906 | * |
907 | * Note: at the moment the RPC client only passes the length of our | |
908 | * scratch buffer in the xdr_buf's header kvec. Previously this | |
909 | * meant we needed to call xdr_adjust_iovec() after encoding the | |
910 | * data. With the new scheme, the xdr_stream manages the details | |
911 | * of the buffer length, and takes care of adjusting the kvec | |
912 | * length for us. | |
913 | */ | |
0ccc61b1 CL |
914 | void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p, |
915 | struct rpc_rqst *rqst) | |
1da177e4 LT |
916 | { |
917 | struct kvec *iov = buf->head; | |
334ccfd5 | 918 | int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len; |
1da177e4 | 919 | |
0ae4c3e8 | 920 | xdr_reset_scratch_buffer(xdr); |
334ccfd5 | 921 | BUG_ON(scratch_len < 0); |
1da177e4 LT |
922 | xdr->buf = buf; |
923 | xdr->iov = iov; | |
d8ed029d AD |
924 | xdr->p = (__be32 *)((char *)iov->iov_base + iov->iov_len); |
925 | xdr->end = (__be32 *)((char *)iov->iov_base + scratch_len); | |
334ccfd5 TM |
926 | BUG_ON(iov->iov_len > scratch_len); |
927 | ||
928 | if (p != xdr->p && p != NULL) { | |
929 | size_t len; | |
930 | ||
931 | BUG_ON(p < xdr->p || p > xdr->end); | |
932 | len = (char *)p - (char *)xdr->p; | |
933 | xdr->p = p; | |
934 | buf->len += len; | |
935 | iov->iov_len += len; | |
936 | } | |
0ccc61b1 | 937 | xdr->rqst = rqst; |
1da177e4 | 938 | } |
468039ee | 939 | EXPORT_SYMBOL_GPL(xdr_init_encode); |
1da177e4 | 940 | |
98124f5b CL |
941 | /** |
942 | * xdr_init_encode_pages - Initialize an xdr_stream for encoding into pages | |
943 | * @xdr: pointer to xdr_stream struct | |
944 | * @buf: pointer to XDR buffer into which to encode data | |
945 | * @pages: list of pages to decode into | |
946 | * @rqst: pointer to controlling rpc_rqst, for debugging | |
947 | * | |
948 | */ | |
949 | void xdr_init_encode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, | |
950 | struct page **pages, struct rpc_rqst *rqst) | |
951 | { | |
952 | xdr_reset_scratch_buffer(xdr); | |
953 | ||
954 | xdr->buf = buf; | |
955 | xdr->page_ptr = pages; | |
956 | xdr->iov = NULL; | |
957 | xdr->p = page_address(*pages); | |
958 | xdr->end = (void *)xdr->p + min_t(u32, buf->buflen, PAGE_SIZE); | |
959 | xdr->rqst = rqst; | |
960 | } | |
961 | EXPORT_SYMBOL_GPL(xdr_init_encode_pages); | |
962 | ||
2825a7f9 | 963 | /** |
62ed448c | 964 | * __xdr_commit_encode - Ensure all data is written to buffer |
2825a7f9 BF |
965 | * @xdr: pointer to xdr_stream |
966 | * | |
967 | * We handle encoding across page boundaries by giving the caller a | |
968 | * temporary location to write to, then later copying the data into | |
969 | * place; xdr_commit_encode does that copying. | |
970 | * | |
971 | * Normally the caller doesn't need to call this directly, as the | |
972 | * following xdr_reserve_space will do it. But an explicit call may be | |
973 | * required at the end of encoding, or any other time when the xdr_buf | |
974 | * data might be read. | |
975 | */ | |
62ed448c | 976 | void __xdr_commit_encode(struct xdr_stream *xdr) |
2825a7f9 | 977 | { |
90d871b3 | 978 | size_t shift = xdr->scratch.iov_len; |
2825a7f9 BF |
979 | void *page; |
980 | ||
2825a7f9 BF |
981 | page = page_address(*xdr->page_ptr); |
982 | memcpy(xdr->scratch.iov_base, page, shift); | |
983 | memmove(page, page + shift, (void *)xdr->p - page); | |
0ae4c3e8 | 984 | xdr_reset_scratch_buffer(xdr); |
2825a7f9 | 985 | } |
62ed448c | 986 | EXPORT_SYMBOL_GPL(__xdr_commit_encode); |
2825a7f9 | 987 | |
62ed448c CL |
988 | /* |
989 | * The buffer space to be reserved crosses the boundary between | |
990 | * xdr->buf->head and xdr->buf->pages, or between two pages | |
991 | * in xdr->buf->pages. | |
992 | */ | |
993 | static noinline __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr, | |
994 | size_t nbytes) | |
2825a7f9 | 995 | { |
2825a7f9 BF |
996 | int space_left; |
997 | int frag1bytes, frag2bytes; | |
da9e94fe | 998 | void *p; |
2825a7f9 BF |
999 | |
1000 | if (nbytes > PAGE_SIZE) | |
5582863f | 1001 | goto out_overflow; /* Bigger buffers require special handling */ |
2825a7f9 | 1002 | if (xdr->buf->len + nbytes > xdr->buf->buflen) |
5582863f | 1003 | goto out_overflow; /* Sorry, we're totally out of space */ |
2825a7f9 BF |
1004 | frag1bytes = (xdr->end - xdr->p) << 2; |
1005 | frag2bytes = nbytes - frag1bytes; | |
1006 | if (xdr->iov) | |
1007 | xdr->iov->iov_len += frag1bytes; | |
05638dc7 | 1008 | else |
2825a7f9 | 1009 | xdr->buf->page_len += frag1bytes; |
05638dc7 | 1010 | xdr->page_ptr++; |
2825a7f9 | 1011 | xdr->iov = NULL; |
bd07a641 | 1012 | |
2825a7f9 BF |
1013 | /* |
1014 | * If the last encode didn't end exactly on a page boundary, the | |
1015 | * next one will straddle boundaries. Encode into the next | |
1016 | * page, then copy it back later in xdr_commit_encode. We use | |
1017 | * the "scratch" iov to track any temporarily unused fragment of | |
1018 | * space at the end of the previous buffer: | |
1019 | */ | |
0ae4c3e8 | 1020 | xdr_set_scratch_buffer(xdr, xdr->p, frag1bytes); |
bd07a641 | 1021 | |
2825a7f9 | 1022 | /* |
bd07a641 CL |
1023 | * xdr->p is where the next encode will start after |
1024 | * xdr_commit_encode() has shifted this one back: | |
2825a7f9 | 1025 | */ |
bd07a641 | 1026 | p = page_address(*xdr->page_ptr); |
da9e94fe | 1027 | xdr->p = p + frag2bytes; |
2825a7f9 | 1028 | space_left = xdr->buf->buflen - xdr->buf->len; |
a23dd544 | 1029 | if (space_left - frag1bytes >= PAGE_SIZE) |
da9e94fe | 1030 | xdr->end = p + PAGE_SIZE; |
6c254bf3 | 1031 | else |
da9e94fe | 1032 | xdr->end = p + space_left - frag1bytes; |
6c254bf3 | 1033 | |
2825a7f9 BF |
1034 | xdr->buf->page_len += frag2bytes; |
1035 | xdr->buf->len += nbytes; | |
1036 | return p; | |
5582863f CL |
1037 | out_overflow: |
1038 | trace_rpc_xdr_overflow(xdr, nbytes); | |
1039 | return NULL; | |
2825a7f9 BF |
1040 | } |
1041 | ||
1da177e4 LT |
1042 | /** |
1043 | * xdr_reserve_space - Reserve buffer space for sending | |
1044 | * @xdr: pointer to xdr_stream | |
1045 | * @nbytes: number of bytes to reserve | |
1046 | * | |
1047 | * Checks that we have enough buffer space to encode 'nbytes' more | |
1048 | * bytes of data. If so, update the total xdr_buf length, and | |
1049 | * adjust the length of the current kvec. | |
1050 | */ | |
d8ed029d | 1051 | __be32 * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes) |
1da177e4 | 1052 | { |
d8ed029d AD |
1053 | __be32 *p = xdr->p; |
1054 | __be32 *q; | |
1da177e4 | 1055 | |
2825a7f9 | 1056 | xdr_commit_encode(xdr); |
1da177e4 LT |
1057 | /* align nbytes on the next 32-bit boundary */ |
1058 | nbytes += 3; | |
1059 | nbytes &= ~3; | |
1060 | q = p + (nbytes >> 2); | |
1061 | if (unlikely(q > xdr->end || q < p)) | |
2825a7f9 | 1062 | return xdr_get_next_encode_buffer(xdr, nbytes); |
1da177e4 | 1063 | xdr->p = q; |
2825a7f9 BF |
1064 | if (xdr->iov) |
1065 | xdr->iov->iov_len += nbytes; | |
1066 | else | |
1067 | xdr->buf->page_len += nbytes; | |
1da177e4 LT |
1068 | xdr->buf->len += nbytes; |
1069 | return p; | |
1070 | } | |
468039ee | 1071 | EXPORT_SYMBOL_GPL(xdr_reserve_space); |
1da177e4 | 1072 | |
403217f3 AS |
1073 | |
1074 | /** | |
1075 | * xdr_reserve_space_vec - Reserves a large amount of buffer space for sending | |
1076 | * @xdr: pointer to xdr_stream | |
1077 | * @vec: pointer to a kvec array | |
1078 | * @nbytes: number of bytes to reserve | |
1079 | * | |
1080 | * Reserves enough buffer space to encode 'nbytes' of data and stores the | |
1081 | * pointers in 'vec'. The size argument passed to xdr_reserve_space() is | |
1082 | * determined based on the number of bytes remaining in the current page to | |
1083 | * avoid invalidating iov_base pointers when xdr_commit_encode() is called. | |
1084 | */ | |
1085 | int xdr_reserve_space_vec(struct xdr_stream *xdr, struct kvec *vec, size_t nbytes) | |
1086 | { | |
1087 | int thislen; | |
1088 | int v = 0; | |
1089 | __be32 *p; | |
1090 | ||
1091 | /* | |
1092 | * svcrdma requires every READ payload to start somewhere | |
1093 | * in xdr->pages. | |
1094 | */ | |
1095 | if (xdr->iov == xdr->buf->head) { | |
1096 | xdr->iov = NULL; | |
1097 | xdr->end = xdr->p; | |
1098 | } | |
1099 | ||
1100 | while (nbytes) { | |
1101 | thislen = xdr->buf->page_len % PAGE_SIZE; | |
1102 | thislen = min_t(size_t, nbytes, PAGE_SIZE - thislen); | |
1103 | ||
1104 | p = xdr_reserve_space(xdr, thislen); | |
1105 | if (!p) | |
1106 | return -EIO; | |
1107 | ||
1108 | vec[v].iov_base = p; | |
1109 | vec[v].iov_len = thislen; | |
1110 | v++; | |
1111 | nbytes -= thislen; | |
1112 | } | |
1113 | ||
1114 | return v; | |
1115 | } | |
1116 | EXPORT_SYMBOL_GPL(xdr_reserve_space_vec); | |
1117 | ||
3e19ce76 BF |
1118 | /** |
1119 | * xdr_truncate_encode - truncate an encode buffer | |
1120 | * @xdr: pointer to xdr_stream | |
1121 | * @len: new length of buffer | |
1122 | * | |
1123 | * Truncates the xdr stream, so that xdr->buf->len == len, | |
1124 | * and xdr->p points at offset len from the start of the buffer, and | |
1125 | * head, tail, and page lengths are adjusted to correspond. | |
1126 | * | |
1127 | * If this means moving xdr->p to a different buffer, we assume that | |
1cc5213b | 1128 | * the end pointer should be set to the end of the current page, |
3e19ce76 BF |
1129 | * except in the case of the head buffer when we assume the head |
1130 | * buffer's current length represents the end of the available buffer. | |
1131 | * | |
1132 | * This is *not* safe to use on a buffer that already has inlined page | |
1133 | * cache pages (as in a zero-copy server read reply), except for the | |
1134 | * simple case of truncating from one position in the tail to another. | |
1135 | * | |
1136 | */ | |
1137 | void xdr_truncate_encode(struct xdr_stream *xdr, size_t len) | |
1138 | { | |
1139 | struct xdr_buf *buf = xdr->buf; | |
1140 | struct kvec *head = buf->head; | |
1141 | struct kvec *tail = buf->tail; | |
1142 | int fraglen; | |
49a068f8 | 1143 | int new; |
3e19ce76 BF |
1144 | |
1145 | if (len > buf->len) { | |
1146 | WARN_ON_ONCE(1); | |
1147 | return; | |
1148 | } | |
2825a7f9 | 1149 | xdr_commit_encode(xdr); |
3e19ce76 BF |
1150 | |
1151 | fraglen = min_t(int, buf->len - len, tail->iov_len); | |
1152 | tail->iov_len -= fraglen; | |
1153 | buf->len -= fraglen; | |
ed38c069 | 1154 | if (tail->iov_len) { |
3e19ce76 | 1155 | xdr->p = tail->iov_base + tail->iov_len; |
280caac0 BF |
1156 | WARN_ON_ONCE(!xdr->end); |
1157 | WARN_ON_ONCE(!xdr->iov); | |
3e19ce76 BF |
1158 | return; |
1159 | } | |
1160 | WARN_ON_ONCE(fraglen); | |
1161 | fraglen = min_t(int, buf->len - len, buf->page_len); | |
1162 | buf->page_len -= fraglen; | |
1163 | buf->len -= fraglen; | |
1164 | ||
1165 | new = buf->page_base + buf->page_len; | |
49a068f8 BF |
1166 | |
1167 | xdr->page_ptr = buf->pages + (new >> PAGE_SHIFT); | |
3e19ce76 | 1168 | |
ed38c069 | 1169 | if (buf->page_len) { |
3e19ce76 BF |
1170 | xdr->p = page_address(*xdr->page_ptr); |
1171 | xdr->end = (void *)xdr->p + PAGE_SIZE; | |
1172 | xdr->p = (void *)xdr->p + (new % PAGE_SIZE); | |
280caac0 | 1173 | WARN_ON_ONCE(xdr->iov); |
3e19ce76 BF |
1174 | return; |
1175 | } | |
5d7a5bcb | 1176 | if (fraglen) |
3e19ce76 BF |
1177 | xdr->end = head->iov_base + head->iov_len; |
1178 | /* (otherwise assume xdr->end is already set) */ | |
5d7a5bcb | 1179 | xdr->page_ptr--; |
3e19ce76 BF |
1180 | head->iov_len = len; |
1181 | buf->len = len; | |
1182 | xdr->p = head->iov_base + head->iov_len; | |
1183 | xdr->iov = buf->head; | |
1184 | } | |
1185 | EXPORT_SYMBOL(xdr_truncate_encode); | |
1186 | ||
b68e4c5c CL |
1187 | /** |
1188 | * xdr_truncate_decode - Truncate a decoding stream | |
1189 | * @xdr: pointer to struct xdr_stream | |
1190 | * @len: Number of bytes to remove | |
1191 | * | |
1192 | */ | |
1193 | void xdr_truncate_decode(struct xdr_stream *xdr, size_t len) | |
1194 | { | |
1195 | unsigned int nbytes = xdr_align_size(len); | |
1196 | ||
1197 | xdr->buf->len -= nbytes; | |
1198 | xdr->nwords -= XDR_QUADLEN(nbytes); | |
1199 | } | |
1200 | EXPORT_SYMBOL_GPL(xdr_truncate_decode); | |
1201 | ||
db3f58a9 BF |
1202 | /** |
1203 | * xdr_restrict_buflen - decrease available buffer space | |
1204 | * @xdr: pointer to xdr_stream | |
1205 | * @newbuflen: new maximum number of bytes available | |
1206 | * | |
1207 | * Adjust our idea of how much space is available in the buffer. | |
1208 | * If we've already used too much space in the buffer, returns -1. | |
1209 | * If the available space is already smaller than newbuflen, returns 0 | |
1210 | * and does nothing. Otherwise, adjusts xdr->buf->buflen to newbuflen | |
1211 | * and ensures xdr->end is set at most offset newbuflen from the start | |
1212 | * of the buffer. | |
1213 | */ | |
1214 | int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen) | |
1215 | { | |
1216 | struct xdr_buf *buf = xdr->buf; | |
1217 | int left_in_this_buf = (void *)xdr->end - (void *)xdr->p; | |
1218 | int end_offset = buf->len + left_in_this_buf; | |
1219 | ||
1220 | if (newbuflen < 0 || newbuflen < buf->len) | |
1221 | return -1; | |
1222 | if (newbuflen > buf->buflen) | |
1223 | return 0; | |
1224 | if (newbuflen < end_offset) | |
1225 | xdr->end = (void *)xdr->end + newbuflen - end_offset; | |
1226 | buf->buflen = newbuflen; | |
1227 | return 0; | |
1228 | } | |
1229 | EXPORT_SYMBOL(xdr_restrict_buflen); | |
1230 | ||
1da177e4 LT |
1231 | /** |
1232 | * xdr_write_pages - Insert a list of pages into an XDR buffer for sending | |
1233 | * @xdr: pointer to xdr_stream | |
ad3d24c5 CL |
1234 | * @pages: array of pages to insert |
1235 | * @base: starting offset of first data byte in @pages | |
1236 | * @len: number of data bytes in @pages to insert | |
1da177e4 | 1237 | * |
ad3d24c5 CL |
1238 | * After the @pages are added, the tail iovec is instantiated pointing to |
1239 | * end of the head buffer, and the stream is set up to encode subsequent | |
1240 | * items into the tail. | |
1da177e4 LT |
1241 | */ |
1242 | void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base, | |
1243 | unsigned int len) | |
1244 | { | |
1245 | struct xdr_buf *buf = xdr->buf; | |
ad3d24c5 CL |
1246 | struct kvec *tail = buf->tail; |
1247 | ||
1da177e4 LT |
1248 | buf->pages = pages; |
1249 | buf->page_base = base; | |
1250 | buf->page_len = len; | |
1251 | ||
ad3d24c5 CL |
1252 | tail->iov_base = xdr->p; |
1253 | tail->iov_len = 0; | |
1254 | xdr->iov = tail; | |
1da177e4 LT |
1255 | |
1256 | if (len & 3) { | |
1257 | unsigned int pad = 4 - (len & 3); | |
1258 | ||
1259 | BUG_ON(xdr->p >= xdr->end); | |
ad3d24c5 CL |
1260 | tail->iov_base = (char *)xdr->p + (len & 3); |
1261 | tail->iov_len += pad; | |
1da177e4 LT |
1262 | len += pad; |
1263 | *xdr->p++ = 0; | |
1264 | } | |
1265 | buf->buflen += len; | |
1266 | buf->len += len; | |
1267 | } | |
468039ee | 1268 | EXPORT_SYMBOL_GPL(xdr_write_pages); |
1da177e4 | 1269 | |
8d86e373 TM |
1270 | static unsigned int xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov, |
1271 | unsigned int base, unsigned int len) | |
6650239a TM |
1272 | { |
1273 | if (len > iov->iov_len) | |
1274 | len = iov->iov_len; | |
8d86e373 TM |
1275 | if (unlikely(base > len)) |
1276 | base = len; | |
1277 | xdr->p = (__be32*)(iov->iov_base + base); | |
6650239a TM |
1278 | xdr->end = (__be32*)(iov->iov_base + len); |
1279 | xdr->iov = iov; | |
1280 | xdr->page_ptr = NULL; | |
8d86e373 | 1281 | return len - base; |
6650239a TM |
1282 | } |
1283 | ||
5a5f1c2c TM |
1284 | static unsigned int xdr_set_tail_base(struct xdr_stream *xdr, |
1285 | unsigned int base, unsigned int len) | |
1286 | { | |
1287 | struct xdr_buf *buf = xdr->buf; | |
1288 | ||
1289 | xdr_stream_set_pos(xdr, base + buf->page_len + buf->head->iov_len); | |
1290 | return xdr_set_iov(xdr, buf->tail, base, len); | |
6650239a TM |
1291 | } |
1292 | ||
8d86e373 TM |
1293 | static unsigned int xdr_set_page_base(struct xdr_stream *xdr, |
1294 | unsigned int base, unsigned int len) | |
6650239a TM |
1295 | { |
1296 | unsigned int pgnr; | |
1297 | unsigned int maxlen; | |
1298 | unsigned int pgoff; | |
1299 | unsigned int pgend; | |
1300 | void *kaddr; | |
1301 | ||
1302 | maxlen = xdr->buf->page_len; | |
6d1c0f3d AS |
1303 | if (base >= maxlen) |
1304 | return 0; | |
1305 | else | |
8d86e373 | 1306 | maxlen -= base; |
6650239a TM |
1307 | if (len > maxlen) |
1308 | len = maxlen; | |
1309 | ||
5a5f1c2c | 1310 | xdr_stream_page_set_pos(xdr, base); |
6650239a TM |
1311 | base += xdr->buf->page_base; |
1312 | ||
1313 | pgnr = base >> PAGE_SHIFT; | |
1314 | xdr->page_ptr = &xdr->buf->pages[pgnr]; | |
1315 | kaddr = page_address(*xdr->page_ptr); | |
1316 | ||
1317 | pgoff = base & ~PAGE_MASK; | |
1318 | xdr->p = (__be32*)(kaddr + pgoff); | |
1319 | ||
1320 | pgend = pgoff + len; | |
1321 | if (pgend > PAGE_SIZE) | |
1322 | pgend = PAGE_SIZE; | |
1323 | xdr->end = (__be32*)(kaddr + pgend); | |
1324 | xdr->iov = NULL; | |
8d86e373 | 1325 | return len; |
6650239a TM |
1326 | } |
1327 | ||
f7d61ee4 AS |
1328 | static void xdr_set_page(struct xdr_stream *xdr, unsigned int base, |
1329 | unsigned int len) | |
1330 | { | |
0279024f TM |
1331 | if (xdr_set_page_base(xdr, base, len) == 0) { |
1332 | base -= xdr->buf->page_len; | |
5a5f1c2c | 1333 | xdr_set_tail_base(xdr, base, len); |
0279024f | 1334 | } |
f7d61ee4 AS |
1335 | } |
1336 | ||
6650239a TM |
1337 | static void xdr_set_next_page(struct xdr_stream *xdr) |
1338 | { | |
1339 | unsigned int newbase; | |
1340 | ||
1341 | newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT; | |
1342 | newbase -= xdr->buf->page_base; | |
0279024f TM |
1343 | if (newbase < xdr->buf->page_len) |
1344 | xdr_set_page_base(xdr, newbase, xdr_stream_remaining(xdr)); | |
1345 | else | |
5a5f1c2c | 1346 | xdr_set_tail_base(xdr, 0, xdr_stream_remaining(xdr)); |
6650239a TM |
1347 | } |
1348 | ||
1349 | static bool xdr_set_next_buffer(struct xdr_stream *xdr) | |
1350 | { | |
1351 | if (xdr->page_ptr != NULL) | |
1352 | xdr_set_next_page(xdr); | |
0279024f TM |
1353 | else if (xdr->iov == xdr->buf->head) |
1354 | xdr_set_page(xdr, 0, xdr_stream_remaining(xdr)); | |
6650239a TM |
1355 | return xdr->p != xdr->end; |
1356 | } | |
1357 | ||
1da177e4 LT |
1358 | /** |
1359 | * xdr_init_decode - Initialize an xdr_stream for decoding data. | |
1360 | * @xdr: pointer to xdr_stream struct | |
1361 | * @buf: pointer to XDR buffer from which to decode data | |
1362 | * @p: current pointer inside XDR buffer | |
0ccc61b1 | 1363 | * @rqst: pointer to controlling rpc_rqst, for debugging |
1da177e4 | 1364 | */ |
0ccc61b1 CL |
1365 | void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p, |
1366 | struct rpc_rqst *rqst) | |
1da177e4 | 1367 | { |
1da177e4 | 1368 | xdr->buf = buf; |
0ae4c3e8 | 1369 | xdr_reset_scratch_buffer(xdr); |
bfeea1dc | 1370 | xdr->nwords = XDR_QUADLEN(buf->len); |
8d86e373 TM |
1371 | if (xdr_set_iov(xdr, buf->head, 0, buf->len) == 0 && |
1372 | xdr_set_page_base(xdr, 0, buf->len) == 0) | |
1373 | xdr_set_iov(xdr, buf->tail, 0, buf->len); | |
bfeea1dc TM |
1374 | if (p != NULL && p > xdr->p && xdr->end >= p) { |
1375 | xdr->nwords -= p - xdr->p; | |
1537693c | 1376 | xdr->p = p; |
bfeea1dc | 1377 | } |
0ccc61b1 | 1378 | xdr->rqst = rqst; |
1da177e4 | 1379 | } |
468039ee | 1380 | EXPORT_SYMBOL_GPL(xdr_init_decode); |
1da177e4 | 1381 | |
f7da7a12 | 1382 | /** |
7ecce75f | 1383 | * xdr_init_decode_pages - Initialize an xdr_stream for decoding into pages |
f7da7a12 BH |
1384 | * @xdr: pointer to xdr_stream struct |
1385 | * @buf: pointer to XDR buffer from which to decode data | |
1386 | * @pages: list of pages to decode into | |
1387 | * @len: length in bytes of buffer in pages | |
1388 | */ | |
1389 | void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, | |
1390 | struct page **pages, unsigned int len) | |
1391 | { | |
1392 | memset(buf, 0, sizeof(*buf)); | |
1393 | buf->pages = pages; | |
1394 | buf->page_len = len; | |
1395 | buf->buflen = len; | |
1396 | buf->len = len; | |
0ccc61b1 | 1397 | xdr_init_decode(xdr, buf, NULL, NULL); |
f7da7a12 BH |
1398 | } |
1399 | EXPORT_SYMBOL_GPL(xdr_init_decode_pages); | |
1400 | ||
6650239a | 1401 | static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) |
ba8e452a | 1402 | { |
bfeea1dc | 1403 | unsigned int nwords = XDR_QUADLEN(nbytes); |
ba8e452a | 1404 | __be32 *p = xdr->p; |
bfeea1dc | 1405 | __be32 *q = p + nwords; |
ba8e452a | 1406 | |
bfeea1dc | 1407 | if (unlikely(nwords > xdr->nwords || q > xdr->end || q < p)) |
ba8e452a | 1408 | return NULL; |
6650239a | 1409 | xdr->p = q; |
bfeea1dc | 1410 | xdr->nwords -= nwords; |
ba8e452a TM |
1411 | return p; |
1412 | } | |
ba8e452a | 1413 | |
6650239a TM |
1414 | static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes) |
1415 | { | |
1416 | __be32 *p; | |
ace0e14f | 1417 | char *cpdest = xdr->scratch.iov_base; |
6650239a TM |
1418 | size_t cplen = (char *)xdr->end - (char *)xdr->p; |
1419 | ||
1420 | if (nbytes > xdr->scratch.iov_len) | |
5582863f | 1421 | goto out_overflow; |
ace0e14f TM |
1422 | p = __xdr_inline_decode(xdr, cplen); |
1423 | if (p == NULL) | |
1424 | return NULL; | |
1425 | memcpy(cpdest, p, cplen); | |
5582863f CL |
1426 | if (!xdr_set_next_buffer(xdr)) |
1427 | goto out_overflow; | |
6650239a TM |
1428 | cpdest += cplen; |
1429 | nbytes -= cplen; | |
6650239a TM |
1430 | p = __xdr_inline_decode(xdr, nbytes); |
1431 | if (p == NULL) | |
1432 | return NULL; | |
1433 | memcpy(cpdest, p, nbytes); | |
1434 | return xdr->scratch.iov_base; | |
5582863f CL |
1435 | out_overflow: |
1436 | trace_rpc_xdr_overflow(xdr, nbytes); | |
1437 | return NULL; | |
6650239a TM |
1438 | } |
1439 | ||
1440 | /** | |
1441 | * xdr_inline_decode - Retrieve XDR data to decode | |
1da177e4 LT |
1442 | * @xdr: pointer to xdr_stream struct |
1443 | * @nbytes: number of bytes of data to decode | |
1444 | * | |
1445 | * Check if the input buffer is long enough to enable us to decode | |
1446 | * 'nbytes' more bytes of data starting at the current position. | |
1447 | * If so return the current pointer, then update the current | |
1448 | * pointer position. | |
1449 | */ | |
d8ed029d | 1450 | __be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) |
1da177e4 | 1451 | { |
6650239a | 1452 | __be32 *p; |
1da177e4 | 1453 | |
5582863f | 1454 | if (unlikely(nbytes == 0)) |
6650239a TM |
1455 | return xdr->p; |
1456 | if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr)) | |
5582863f | 1457 | goto out_overflow; |
6650239a TM |
1458 | p = __xdr_inline_decode(xdr, nbytes); |
1459 | if (p != NULL) | |
1460 | return p; | |
1461 | return xdr_copy_to_scratch(xdr, nbytes); | |
5582863f CL |
1462 | out_overflow: |
1463 | trace_rpc_xdr_overflow(xdr, nbytes); | |
1464 | return NULL; | |
1da177e4 | 1465 | } |
468039ee | 1466 | EXPORT_SYMBOL_GPL(xdr_inline_decode); |
1da177e4 | 1467 | |
06216ecb | 1468 | static void xdr_realign_pages(struct xdr_stream *xdr) |
1da177e4 LT |
1469 | { |
1470 | struct xdr_buf *buf = xdr->buf; | |
06216ecb | 1471 | struct kvec *iov = buf->head; |
b760b313 | 1472 | unsigned int cur = xdr_stream_pos(xdr); |
6707fbd7 | 1473 | unsigned int copied; |
1da177e4 LT |
1474 | |
1475 | /* Realign pages to current pointer position */ | |
a11a2bf4 | 1476 | if (iov->iov_len > cur) { |
6707fbd7 TM |
1477 | copied = xdr_shrink_bufhead(buf, cur); |
1478 | trace_rpc_xdr_alignment(xdr, cur, copied); | |
5a5f1c2c | 1479 | xdr_set_page(xdr, 0, buf->page_len); |
a11a2bf4 | 1480 | } |
06216ecb AS |
1481 | } |
1482 | ||
1483 | static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len) | |
1484 | { | |
1485 | struct xdr_buf *buf = xdr->buf; | |
1486 | unsigned int nwords = XDR_QUADLEN(len); | |
c4f2f591 | 1487 | unsigned int copied; |
06216ecb AS |
1488 | |
1489 | if (xdr->nwords == 0) | |
1490 | return 0; | |
1da177e4 | 1491 | |
06216ecb | 1492 | xdr_realign_pages(xdr); |
a11a2bf4 TM |
1493 | if (nwords > xdr->nwords) { |
1494 | nwords = xdr->nwords; | |
1495 | len = nwords << 2; | |
1496 | } | |
1497 | if (buf->page_len <= len) | |
8a9a8b83 | 1498 | len = buf->page_len; |
a11a2bf4 TM |
1499 | else if (nwords < xdr->nwords) { |
1500 | /* Truncate page data and move it into the tail */ | |
c4f2f591 TM |
1501 | copied = xdr_shrink_pagelen(buf, len); |
1502 | trace_rpc_xdr_alignment(xdr, len, copied); | |
a11a2bf4 | 1503 | } |
3994ee6f TM |
1504 | return len; |
1505 | } | |
bd00f84b | 1506 | |
1da177e4 | 1507 | /** |
1d973166 | 1508 | * xdr_read_pages - align page-based XDR data to current pointer position |
1da177e4 LT |
1509 | * @xdr: pointer to xdr_stream struct |
1510 | * @len: number of bytes of page data | |
1511 | * | |
1512 | * Moves data beyond the current pointer position from the XDR head[] buffer | |
1d973166 TM |
1513 | * into the page list. Any data that lies beyond current position + @len |
1514 | * bytes is moved into the XDR tail[]. The xdr_stream current position is | |
1515 | * then advanced past that data to align to the next XDR object in the tail. | |
3994ee6f TM |
1516 | * |
1517 | * Returns the number of XDR encoded bytes now contained in the pages | |
1da177e4 | 1518 | */ |
3994ee6f | 1519 | unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len) |
1da177e4 | 1520 | { |
1d973166 TM |
1521 | unsigned int nwords = XDR_QUADLEN(len); |
1522 | unsigned int base, end, pglen; | |
1da177e4 | 1523 | |
1d973166 TM |
1524 | pglen = xdr_align_pages(xdr, nwords << 2); |
1525 | if (pglen == 0) | |
3994ee6f | 1526 | return 0; |
bd00f84b | 1527 | |
1d973166 TM |
1528 | base = (nwords << 2) - pglen; |
1529 | end = xdr_stream_remaining(xdr) - pglen; | |
1530 | ||
5a5f1c2c | 1531 | xdr_set_tail_base(xdr, base, end); |
1d973166 | 1532 | return len <= pglen ? len : pglen; |
1da177e4 | 1533 | } |
468039ee | 1534 | EXPORT_SYMBOL_GPL(xdr_read_pages); |
1da177e4 | 1535 | |
7c4cd5f4 AS |
1536 | /** |
1537 | * xdr_set_pagelen - Sets the length of the XDR pages | |
1538 | * @xdr: pointer to xdr_stream struct | |
1539 | * @len: new length of the XDR page data | |
1540 | * | |
1541 | * Either grows or shrinks the length of the xdr pages by setting pagelen to | |
1542 | * @len bytes. When shrinking, any extra data is moved into buf->tail, whereas | |
1543 | * when growing any data beyond the current pointer is moved into the tail. | |
1544 | * | |
1545 | * Returns True if the operation was successful, and False otherwise. | |
1546 | */ | |
1547 | void xdr_set_pagelen(struct xdr_stream *xdr, unsigned int len) | |
1548 | { | |
1549 | struct xdr_buf *buf = xdr->buf; | |
1550 | size_t remaining = xdr_stream_remaining(xdr); | |
1551 | size_t base = 0; | |
1552 | ||
1553 | if (len < buf->page_len) { | |
1554 | base = buf->page_len - len; | |
1555 | xdr_shrink_pagelen(buf, len); | |
1556 | } else { | |
1557 | xdr_buf_head_shift_right(buf, xdr_stream_pos(xdr), | |
1558 | buf->page_len, remaining); | |
1559 | if (len > buf->page_len) | |
1560 | xdr_buf_try_expand(buf, len - buf->page_len); | |
1561 | } | |
1562 | xdr_set_tail_base(xdr, base, remaining); | |
1563 | } | |
1564 | EXPORT_SYMBOL_GPL(xdr_set_pagelen); | |
1565 | ||
8b23ea7b TM |
1566 | /** |
1567 | * xdr_enter_page - decode data from the XDR page | |
1568 | * @xdr: pointer to xdr_stream struct | |
1569 | * @len: number of bytes of page data | |
1570 | * | |
1571 | * Moves data beyond the current pointer position from the XDR head[] buffer | |
1572 | * into the page list. Any data that lies beyond current position + "len" | |
1573 | * bytes is moved into the XDR tail[]. The current pointer is then | |
1574 | * repositioned at the beginning of the first XDR page. | |
1575 | */ | |
1576 | void xdr_enter_page(struct xdr_stream *xdr, unsigned int len) | |
1577 | { | |
f8bb7f08 | 1578 | len = xdr_align_pages(xdr, len); |
8b23ea7b TM |
1579 | /* |
1580 | * Position current pointer at beginning of tail, and | |
1581 | * set remaining message length. | |
1582 | */ | |
f8bb7f08 TM |
1583 | if (len != 0) |
1584 | xdr_set_page_base(xdr, 0, len); | |
8b23ea7b | 1585 | } |
468039ee | 1586 | EXPORT_SYMBOL_GPL(xdr_enter_page); |
8b23ea7b | 1587 | |
c2bd2c0a | 1588 | static const struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0}; |
1da177e4 | 1589 | |
f8d0e60f | 1590 | void xdr_buf_from_iov(const struct kvec *iov, struct xdr_buf *buf) |
1da177e4 LT |
1591 | { |
1592 | buf->head[0] = *iov; | |
1593 | buf->tail[0] = empty_iov; | |
1594 | buf->page_len = 0; | |
1595 | buf->buflen = buf->len = iov->iov_len; | |
1596 | } | |
468039ee | 1597 | EXPORT_SYMBOL_GPL(xdr_buf_from_iov); |
1da177e4 | 1598 | |
de4aee2e BF |
1599 | /** |
1600 | * xdr_buf_subsegment - set subbuf to a portion of buf | |
1601 | * @buf: an xdr buffer | |
1602 | * @subbuf: the result buffer | |
1603 | * @base: beginning of range in bytes | |
1604 | * @len: length of range in bytes | |
1605 | * | |
1606 | * sets @subbuf to an xdr buffer representing the portion of @buf of | |
1607 | * length @len starting at offset @base. | |
1608 | * | |
1609 | * @buf and @subbuf may be pointers to the same struct xdr_buf. | |
1610 | * | |
b8ab2a6f | 1611 | * Returns -1 if base or length are out of bounds. |
de4aee2e | 1612 | */ |
5a7e7026 CL |
1613 | int xdr_buf_subsegment(const struct xdr_buf *buf, struct xdr_buf *subbuf, |
1614 | unsigned int base, unsigned int len) | |
1da177e4 | 1615 | { |
1da177e4 | 1616 | subbuf->buflen = subbuf->len = len; |
1e78957e TM |
1617 | if (base < buf->head[0].iov_len) { |
1618 | subbuf->head[0].iov_base = buf->head[0].iov_base + base; | |
1619 | subbuf->head[0].iov_len = min_t(unsigned int, len, | |
1620 | buf->head[0].iov_len - base); | |
1621 | len -= subbuf->head[0].iov_len; | |
1622 | base = 0; | |
1623 | } else { | |
1e78957e | 1624 | base -= buf->head[0].iov_len; |
89a3c9f5 | 1625 | subbuf->head[0].iov_base = buf->head[0].iov_base; |
de4aee2e | 1626 | subbuf->head[0].iov_len = 0; |
1e78957e | 1627 | } |
1da177e4 LT |
1628 | |
1629 | if (base < buf->page_len) { | |
1e78957e TM |
1630 | subbuf->page_len = min(buf->page_len - base, len); |
1631 | base += buf->page_base; | |
09cbfeaf KS |
1632 | subbuf->page_base = base & ~PAGE_MASK; |
1633 | subbuf->pages = &buf->pages[base >> PAGE_SHIFT]; | |
1da177e4 LT |
1634 | len -= subbuf->page_len; |
1635 | base = 0; | |
1636 | } else { | |
1637 | base -= buf->page_len; | |
89a3c9f5 CL |
1638 | subbuf->pages = buf->pages; |
1639 | subbuf->page_base = 0; | |
1da177e4 LT |
1640 | subbuf->page_len = 0; |
1641 | } | |
1642 | ||
1e78957e TM |
1643 | if (base < buf->tail[0].iov_len) { |
1644 | subbuf->tail[0].iov_base = buf->tail[0].iov_base + base; | |
1645 | subbuf->tail[0].iov_len = min_t(unsigned int, len, | |
1646 | buf->tail[0].iov_len - base); | |
1647 | len -= subbuf->tail[0].iov_len; | |
1648 | base = 0; | |
1649 | } else { | |
1e78957e | 1650 | base -= buf->tail[0].iov_len; |
89a3c9f5 | 1651 | subbuf->tail[0].iov_base = buf->tail[0].iov_base; |
de4aee2e | 1652 | subbuf->tail[0].iov_len = 0; |
1e78957e TM |
1653 | } |
1654 | ||
1da177e4 LT |
1655 | if (base || len) |
1656 | return -1; | |
1657 | return 0; | |
1658 | } | |
468039ee | 1659 | EXPORT_SYMBOL_GPL(xdr_buf_subsegment); |
1da177e4 | 1660 | |
c1346a12 CL |
1661 | /** |
1662 | * xdr_stream_subsegment - set @subbuf to a portion of @xdr | |
1663 | * @xdr: an xdr_stream set up for decoding | |
1664 | * @subbuf: the result buffer | |
1665 | * @nbytes: length of @xdr to extract, in bytes | |
1666 | * | |
1667 | * Sets up @subbuf to represent a portion of @xdr. The portion | |
1668 | * starts at the current offset in @xdr, and extends for a length | |
1669 | * of @nbytes. If this is successful, @xdr is advanced to the next | |
f49b68dd | 1670 | * XDR data item following that portion. |
c1346a12 CL |
1671 | * |
1672 | * Return values: | |
1673 | * %true: @subbuf has been initialized, and @xdr has been advanced. | |
1674 | * %false: a bounds error has occurred | |
1675 | */ | |
1676 | bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf, | |
1677 | unsigned int nbytes) | |
1678 | { | |
f49b68dd CL |
1679 | unsigned int start = xdr_stream_pos(xdr); |
1680 | unsigned int remaining, len; | |
c1346a12 | 1681 | |
f49b68dd CL |
1682 | /* Extract @subbuf and bounds-check the fn arguments */ |
1683 | if (xdr_buf_subsegment(xdr->buf, subbuf, start, nbytes)) | |
c1346a12 CL |
1684 | return false; |
1685 | ||
f49b68dd CL |
1686 | /* Advance @xdr by @nbytes */ |
1687 | for (remaining = nbytes; remaining;) { | |
c1346a12 CL |
1688 | if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr)) |
1689 | return false; | |
c1346a12 | 1690 | |
f49b68dd CL |
1691 | len = (char *)xdr->end - (char *)xdr->p; |
1692 | if (remaining <= len) { | |
1693 | xdr->p = (__be32 *)((char *)xdr->p + | |
1694 | (remaining + xdr_pad_size(nbytes))); | |
1695 | break; | |
1696 | } | |
1697 | ||
1698 | xdr->p = (__be32 *)((char *)xdr->p + len); | |
1699 | xdr->end = xdr->p; | |
c1346a12 | 1700 | remaining -= len; |
c1346a12 CL |
1701 | } |
1702 | ||
f49b68dd | 1703 | xdr_stream_set_pos(xdr, start + nbytes); |
c1346a12 CL |
1704 | return true; |
1705 | } | |
1706 | EXPORT_SYMBOL_GPL(xdr_stream_subsegment); | |
1707 | ||
4f5f3b60 AS |
1708 | /** |
1709 | * xdr_stream_move_subsegment - Move part of a stream to another position | |
1710 | * @xdr: the source xdr_stream | |
1711 | * @offset: the source offset of the segment | |
1712 | * @target: the target offset of the segment | |
1713 | * @length: the number of bytes to move | |
1714 | * | |
1715 | * Moves @length bytes from @offset to @target in the xdr_stream, overwriting | |
1716 | * anything in its space. Returns the number of bytes in the segment. | |
1717 | */ | |
1718 | unsigned int xdr_stream_move_subsegment(struct xdr_stream *xdr, unsigned int offset, | |
1719 | unsigned int target, unsigned int length) | |
1720 | { | |
1721 | struct xdr_buf buf; | |
1722 | unsigned int shift; | |
1723 | ||
1724 | if (offset < target) { | |
1725 | shift = target - offset; | |
1726 | if (xdr_buf_subsegment(xdr->buf, &buf, offset, shift + length) < 0) | |
1727 | return 0; | |
1728 | xdr_buf_head_shift_right(&buf, 0, length, shift); | |
1729 | } else if (offset > target) { | |
1730 | shift = offset - target; | |
1731 | if (xdr_buf_subsegment(xdr->buf, &buf, target, shift + length) < 0) | |
1732 | return 0; | |
1733 | xdr_buf_head_shift_left(&buf, shift, length, shift); | |
1734 | } | |
1735 | return length; | |
1736 | } | |
1737 | EXPORT_SYMBOL_GPL(xdr_stream_move_subsegment); | |
1738 | ||
e1bd8760 AS |
1739 | /** |
1740 | * xdr_stream_zero - zero out a portion of an xdr_stream | |
1741 | * @xdr: an xdr_stream to zero out | |
1742 | * @offset: the starting point in the stream | |
1743 | * @length: the number of bytes to zero | |
1744 | */ | |
1745 | unsigned int xdr_stream_zero(struct xdr_stream *xdr, unsigned int offset, | |
1746 | unsigned int length) | |
1747 | { | |
1748 | struct xdr_buf buf; | |
1749 | ||
1750 | if (xdr_buf_subsegment(xdr->buf, &buf, offset, length) < 0) | |
1751 | return 0; | |
1752 | if (buf.head[0].iov_len) | |
1753 | xdr_buf_iov_zero(buf.head, 0, buf.head[0].iov_len); | |
1754 | if (buf.page_len > 0) | |
1755 | xdr_buf_pages_zero(&buf, 0, buf.page_len); | |
1756 | if (buf.tail[0].iov_len) | |
1757 | xdr_buf_iov_zero(buf.tail, 0, buf.tail[0].iov_len); | |
1758 | return length; | |
1759 | } | |
1760 | EXPORT_SYMBOL_GPL(xdr_stream_zero); | |
1761 | ||
0a8e7b7d CL |
1762 | /** |
1763 | * xdr_buf_trim - lop at most "len" bytes off the end of "buf" | |
1764 | * @buf: buf to be trimmed | |
1765 | * @len: number of bytes to reduce "buf" by | |
1766 | * | |
1767 | * Trim an xdr_buf by the given number of bytes by fixing up the lengths. Note | |
1768 | * that it's possible that we'll trim less than that amount if the xdr_buf is | |
1769 | * too small, or if (for instance) it's all in the head and the parser has | |
1770 | * already read too far into it. | |
1771 | */ | |
1772 | void xdr_buf_trim(struct xdr_buf *buf, unsigned int len) | |
1773 | { | |
1774 | size_t cur; | |
1775 | unsigned int trim = len; | |
1776 | ||
1777 | if (buf->tail[0].iov_len) { | |
1778 | cur = min_t(size_t, buf->tail[0].iov_len, trim); | |
1779 | buf->tail[0].iov_len -= cur; | |
1780 | trim -= cur; | |
1781 | if (!trim) | |
1782 | goto fix_len; | |
1783 | } | |
1784 | ||
1785 | if (buf->page_len) { | |
1786 | cur = min_t(unsigned int, buf->page_len, trim); | |
1787 | buf->page_len -= cur; | |
1788 | trim -= cur; | |
1789 | if (!trim) | |
1790 | goto fix_len; | |
1791 | } | |
1792 | ||
1793 | if (buf->head[0].iov_len) { | |
1794 | cur = min_t(size_t, buf->head[0].iov_len, trim); | |
1795 | buf->head[0].iov_len -= cur; | |
1796 | trim -= cur; | |
1797 | } | |
1798 | fix_len: | |
1799 | buf->len -= (len - trim); | |
1800 | } | |
1801 | EXPORT_SYMBOL_GPL(xdr_buf_trim); | |
1802 | ||
f8d0e60f TM |
1803 | static void __read_bytes_from_xdr_buf(const struct xdr_buf *subbuf, |
1804 | void *obj, unsigned int len) | |
1da177e4 | 1805 | { |
1e78957e | 1806 | unsigned int this_len; |
1da177e4 | 1807 | |
4e3e43ad TM |
1808 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); |
1809 | memcpy(obj, subbuf->head[0].iov_base, this_len); | |
1da177e4 LT |
1810 | len -= this_len; |
1811 | obj += this_len; | |
4e3e43ad | 1812 | this_len = min_t(unsigned int, len, subbuf->page_len); |
e43ac22b | 1813 | _copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len); |
1da177e4 LT |
1814 | len -= this_len; |
1815 | obj += this_len; | |
4e3e43ad TM |
1816 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
1817 | memcpy(obj, subbuf->tail[0].iov_base, this_len); | |
1da177e4 LT |
1818 | } |
1819 | ||
bd8100e7 | 1820 | /* obj is assumed to point to allocated memory of size at least len: */ |
f8d0e60f TM |
1821 | int read_bytes_from_xdr_buf(const struct xdr_buf *buf, unsigned int base, |
1822 | void *obj, unsigned int len) | |
bd8100e7 AG |
1823 | { |
1824 | struct xdr_buf subbuf; | |
bd8100e7 AG |
1825 | int status; |
1826 | ||
1827 | status = xdr_buf_subsegment(buf, &subbuf, base, len); | |
4e3e43ad TM |
1828 | if (status != 0) |
1829 | return status; | |
1830 | __read_bytes_from_xdr_buf(&subbuf, obj, len); | |
1831 | return 0; | |
1832 | } | |
468039ee | 1833 | EXPORT_SYMBOL_GPL(read_bytes_from_xdr_buf); |
4e3e43ad | 1834 | |
f8d0e60f TM |
1835 | static void __write_bytes_to_xdr_buf(const struct xdr_buf *subbuf, |
1836 | void *obj, unsigned int len) | |
4e3e43ad TM |
1837 | { |
1838 | unsigned int this_len; | |
1839 | ||
1840 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); | |
1841 | memcpy(subbuf->head[0].iov_base, obj, this_len); | |
bd8100e7 AG |
1842 | len -= this_len; |
1843 | obj += this_len; | |
4e3e43ad | 1844 | this_len = min_t(unsigned int, len, subbuf->page_len); |
e43ac22b | 1845 | _copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len); |
bd8100e7 AG |
1846 | len -= this_len; |
1847 | obj += this_len; | |
4e3e43ad TM |
1848 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
1849 | memcpy(subbuf->tail[0].iov_base, obj, this_len); | |
1850 | } | |
1851 | ||
1852 | /* obj is assumed to point to allocated memory of size at least len: */ | |
f8d0e60f TM |
1853 | int write_bytes_to_xdr_buf(const struct xdr_buf *buf, unsigned int base, |
1854 | void *obj, unsigned int len) | |
4e3e43ad TM |
1855 | { |
1856 | struct xdr_buf subbuf; | |
1857 | int status; | |
1858 | ||
1859 | status = xdr_buf_subsegment(buf, &subbuf, base, len); | |
1860 | if (status != 0) | |
1861 | return status; | |
1862 | __write_bytes_to_xdr_buf(&subbuf, obj, len); | |
1863 | return 0; | |
bd8100e7 | 1864 | } |
c43abaed | 1865 | EXPORT_SYMBOL_GPL(write_bytes_to_xdr_buf); |
bd8100e7 | 1866 | |
f8d0e60f | 1867 | int xdr_decode_word(const struct xdr_buf *buf, unsigned int base, u32 *obj) |
1da177e4 | 1868 | { |
d8ed029d | 1869 | __be32 raw; |
1da177e4 LT |
1870 | int status; |
1871 | ||
1872 | status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj)); | |
1873 | if (status) | |
1874 | return status; | |
98866b5a | 1875 | *obj = be32_to_cpu(raw); |
1da177e4 LT |
1876 | return 0; |
1877 | } | |
468039ee | 1878 | EXPORT_SYMBOL_GPL(xdr_decode_word); |
1da177e4 | 1879 | |
f8d0e60f | 1880 | int xdr_encode_word(const struct xdr_buf *buf, unsigned int base, u32 obj) |
bd8100e7 | 1881 | { |
9f162d2a | 1882 | __be32 raw = cpu_to_be32(obj); |
bd8100e7 AG |
1883 | |
1884 | return write_bytes_to_xdr_buf(buf, base, &raw, sizeof(obj)); | |
1885 | } | |
468039ee | 1886 | EXPORT_SYMBOL_GPL(xdr_encode_word); |
bd8100e7 | 1887 | |
bd8100e7 | 1888 | /* Returns 0 on success, or else a negative error code. */ |
f8d0e60f TM |
1889 | static int xdr_xcode_array2(const struct xdr_buf *buf, unsigned int base, |
1890 | struct xdr_array2_desc *desc, int encode) | |
bd8100e7 AG |
1891 | { |
1892 | char *elem = NULL, *c; | |
1893 | unsigned int copied = 0, todo, avail_here; | |
1894 | struct page **ppages = NULL; | |
1895 | int err; | |
1896 | ||
1897 | if (encode) { | |
1898 | if (xdr_encode_word(buf, base, desc->array_len) != 0) | |
1899 | return -EINVAL; | |
1900 | } else { | |
1901 | if (xdr_decode_word(buf, base, &desc->array_len) != 0 || | |
58fcb8df | 1902 | desc->array_len > desc->array_maxlen || |
bd8100e7 AG |
1903 | (unsigned long) base + 4 + desc->array_len * |
1904 | desc->elem_size > buf->len) | |
1905 | return -EINVAL; | |
1906 | } | |
1907 | base += 4; | |
1908 | ||
1909 | if (!desc->xcode) | |
1910 | return 0; | |
1911 | ||
1912 | todo = desc->array_len * desc->elem_size; | |
1913 | ||
1914 | /* process head */ | |
1915 | if (todo && base < buf->head->iov_len) { | |
1916 | c = buf->head->iov_base + base; | |
1917 | avail_here = min_t(unsigned int, todo, | |
1918 | buf->head->iov_len - base); | |
1919 | todo -= avail_here; | |
1920 | ||
1921 | while (avail_here >= desc->elem_size) { | |
1922 | err = desc->xcode(desc, c); | |
1923 | if (err) | |
1924 | goto out; | |
1925 | c += desc->elem_size; | |
1926 | avail_here -= desc->elem_size; | |
1927 | } | |
1928 | if (avail_here) { | |
1929 | if (!elem) { | |
1930 | elem = kmalloc(desc->elem_size, GFP_KERNEL); | |
1931 | err = -ENOMEM; | |
1932 | if (!elem) | |
1933 | goto out; | |
1934 | } | |
1935 | if (encode) { | |
1936 | err = desc->xcode(desc, elem); | |
1937 | if (err) | |
1938 | goto out; | |
1939 | memcpy(c, elem, avail_here); | |
1940 | } else | |
1941 | memcpy(elem, c, avail_here); | |
1942 | copied = avail_here; | |
1943 | } | |
1944 | base = buf->head->iov_len; /* align to start of pages */ | |
1945 | } | |
1946 | ||
1947 | /* process pages array */ | |
1948 | base -= buf->head->iov_len; | |
1949 | if (todo && base < buf->page_len) { | |
1950 | unsigned int avail_page; | |
1951 | ||
1952 | avail_here = min(todo, buf->page_len - base); | |
1953 | todo -= avail_here; | |
1954 | ||
1955 | base += buf->page_base; | |
09cbfeaf KS |
1956 | ppages = buf->pages + (base >> PAGE_SHIFT); |
1957 | base &= ~PAGE_MASK; | |
1958 | avail_page = min_t(unsigned int, PAGE_SIZE - base, | |
bd8100e7 AG |
1959 | avail_here); |
1960 | c = kmap(*ppages) + base; | |
1961 | ||
1962 | while (avail_here) { | |
1963 | avail_here -= avail_page; | |
1964 | if (copied || avail_page < desc->elem_size) { | |
1965 | unsigned int l = min(avail_page, | |
1966 | desc->elem_size - copied); | |
1967 | if (!elem) { | |
1968 | elem = kmalloc(desc->elem_size, | |
1969 | GFP_KERNEL); | |
1970 | err = -ENOMEM; | |
1971 | if (!elem) | |
1972 | goto out; | |
1973 | } | |
1974 | if (encode) { | |
1975 | if (!copied) { | |
1976 | err = desc->xcode(desc, elem); | |
1977 | if (err) | |
1978 | goto out; | |
1979 | } | |
1980 | memcpy(c, elem + copied, l); | |
1981 | copied += l; | |
1982 | if (copied == desc->elem_size) | |
1983 | copied = 0; | |
1984 | } else { | |
1985 | memcpy(elem + copied, c, l); | |
1986 | copied += l; | |
1987 | if (copied == desc->elem_size) { | |
1988 | err = desc->xcode(desc, elem); | |
1989 | if (err) | |
1990 | goto out; | |
1991 | copied = 0; | |
1992 | } | |
1993 | } | |
1994 | avail_page -= l; | |
1995 | c += l; | |
1996 | } | |
1997 | while (avail_page >= desc->elem_size) { | |
1998 | err = desc->xcode(desc, c); | |
1999 | if (err) | |
2000 | goto out; | |
2001 | c += desc->elem_size; | |
2002 | avail_page -= desc->elem_size; | |
2003 | } | |
2004 | if (avail_page) { | |
2005 | unsigned int l = min(avail_page, | |
2006 | desc->elem_size - copied); | |
2007 | if (!elem) { | |
2008 | elem = kmalloc(desc->elem_size, | |
2009 | GFP_KERNEL); | |
2010 | err = -ENOMEM; | |
2011 | if (!elem) | |
2012 | goto out; | |
2013 | } | |
2014 | if (encode) { | |
2015 | if (!copied) { | |
2016 | err = desc->xcode(desc, elem); | |
2017 | if (err) | |
2018 | goto out; | |
2019 | } | |
2020 | memcpy(c, elem + copied, l); | |
2021 | copied += l; | |
2022 | if (copied == desc->elem_size) | |
2023 | copied = 0; | |
2024 | } else { | |
2025 | memcpy(elem + copied, c, l); | |
2026 | copied += l; | |
2027 | if (copied == desc->elem_size) { | |
2028 | err = desc->xcode(desc, elem); | |
2029 | if (err) | |
2030 | goto out; | |
2031 | copied = 0; | |
2032 | } | |
2033 | } | |
2034 | } | |
2035 | if (avail_here) { | |
2036 | kunmap(*ppages); | |
2037 | ppages++; | |
2038 | c = kmap(*ppages); | |
2039 | } | |
2040 | ||
2041 | avail_page = min(avail_here, | |
09cbfeaf | 2042 | (unsigned int) PAGE_SIZE); |
bd8100e7 AG |
2043 | } |
2044 | base = buf->page_len; /* align to start of tail */ | |
2045 | } | |
2046 | ||
2047 | /* process tail */ | |
2048 | base -= buf->page_len; | |
2049 | if (todo) { | |
2050 | c = buf->tail->iov_base + base; | |
2051 | if (copied) { | |
2052 | unsigned int l = desc->elem_size - copied; | |
2053 | ||
2054 | if (encode) | |
2055 | memcpy(c, elem + copied, l); | |
2056 | else { | |
2057 | memcpy(elem + copied, c, l); | |
2058 | err = desc->xcode(desc, elem); | |
2059 | if (err) | |
2060 | goto out; | |
2061 | } | |
2062 | todo -= l; | |
2063 | c += l; | |
2064 | } | |
2065 | while (todo) { | |
2066 | err = desc->xcode(desc, c); | |
2067 | if (err) | |
2068 | goto out; | |
2069 | c += desc->elem_size; | |
2070 | todo -= desc->elem_size; | |
2071 | } | |
2072 | } | |
2073 | err = 0; | |
2074 | ||
2075 | out: | |
a51482bd | 2076 | kfree(elem); |
bd8100e7 AG |
2077 | if (ppages) |
2078 | kunmap(*ppages); | |
2079 | return err; | |
2080 | } | |
2081 | ||
f8d0e60f TM |
2082 | int xdr_decode_array2(const struct xdr_buf *buf, unsigned int base, |
2083 | struct xdr_array2_desc *desc) | |
bd8100e7 AG |
2084 | { |
2085 | if (base >= buf->len) | |
2086 | return -EINVAL; | |
2087 | ||
2088 | return xdr_xcode_array2(buf, base, desc, 0); | |
2089 | } | |
468039ee | 2090 | EXPORT_SYMBOL_GPL(xdr_decode_array2); |
bd8100e7 | 2091 | |
f8d0e60f TM |
2092 | int xdr_encode_array2(const struct xdr_buf *buf, unsigned int base, |
2093 | struct xdr_array2_desc *desc) | |
bd8100e7 AG |
2094 | { |
2095 | if ((unsigned long) base + 4 + desc->array_len * desc->elem_size > | |
2096 | buf->head->iov_len + buf->page_len + buf->tail->iov_len) | |
2097 | return -EINVAL; | |
2098 | ||
2099 | return xdr_xcode_array2(buf, base, desc, 1); | |
2100 | } | |
468039ee | 2101 | EXPORT_SYMBOL_GPL(xdr_encode_array2); |
37a4e6cb | 2102 | |
f8d0e60f TM |
2103 | int xdr_process_buf(const struct xdr_buf *buf, unsigned int offset, |
2104 | unsigned int len, | |
2105 | int (*actor)(struct scatterlist *, void *), void *data) | |
37a4e6cb OK |
2106 | { |
2107 | int i, ret = 0; | |
95c96174 | 2108 | unsigned int page_len, thislen, page_offset; |
37a4e6cb OK |
2109 | struct scatterlist sg[1]; |
2110 | ||
68e3f5dd HX |
2111 | sg_init_table(sg, 1); |
2112 | ||
37a4e6cb OK |
2113 | if (offset >= buf->head[0].iov_len) { |
2114 | offset -= buf->head[0].iov_len; | |
2115 | } else { | |
2116 | thislen = buf->head[0].iov_len - offset; | |
2117 | if (thislen > len) | |
2118 | thislen = len; | |
2119 | sg_set_buf(sg, buf->head[0].iov_base + offset, thislen); | |
2120 | ret = actor(sg, data); | |
2121 | if (ret) | |
2122 | goto out; | |
2123 | offset = 0; | |
2124 | len -= thislen; | |
2125 | } | |
2126 | if (len == 0) | |
2127 | goto out; | |
2128 | ||
2129 | if (offset >= buf->page_len) { | |
2130 | offset -= buf->page_len; | |
2131 | } else { | |
2132 | page_len = buf->page_len - offset; | |
2133 | if (page_len > len) | |
2134 | page_len = len; | |
2135 | len -= page_len; | |
09cbfeaf KS |
2136 | page_offset = (offset + buf->page_base) & (PAGE_SIZE - 1); |
2137 | i = (offset + buf->page_base) >> PAGE_SHIFT; | |
2138 | thislen = PAGE_SIZE - page_offset; | |
37a4e6cb OK |
2139 | do { |
2140 | if (thislen > page_len) | |
2141 | thislen = page_len; | |
642f1490 | 2142 | sg_set_page(sg, buf->pages[i], thislen, page_offset); |
37a4e6cb OK |
2143 | ret = actor(sg, data); |
2144 | if (ret) | |
2145 | goto out; | |
2146 | page_len -= thislen; | |
2147 | i++; | |
2148 | page_offset = 0; | |
09cbfeaf | 2149 | thislen = PAGE_SIZE; |
37a4e6cb OK |
2150 | } while (page_len != 0); |
2151 | offset = 0; | |
2152 | } | |
2153 | if (len == 0) | |
2154 | goto out; | |
2155 | if (offset < buf->tail[0].iov_len) { | |
2156 | thislen = buf->tail[0].iov_len - offset; | |
2157 | if (thislen > len) | |
2158 | thislen = len; | |
2159 | sg_set_buf(sg, buf->tail[0].iov_base + offset, thislen); | |
2160 | ret = actor(sg, data); | |
2161 | len -= thislen; | |
2162 | } | |
2163 | if (len != 0) | |
2164 | ret = -EINVAL; | |
2165 | out: | |
2166 | return ret; | |
2167 | } | |
468039ee | 2168 | EXPORT_SYMBOL_GPL(xdr_process_buf); |
37a4e6cb | 2169 | |
0e779aa7 TM |
2170 | /** |
2171 | * xdr_stream_decode_opaque - Decode variable length opaque | |
2172 | * @xdr: pointer to xdr_stream | |
2173 | * @ptr: location to store opaque data | |
2174 | * @size: size of storage buffer @ptr | |
2175 | * | |
2176 | * Return values: | |
2177 | * On success, returns size of object stored in *@ptr | |
2178 | * %-EBADMSG on XDR buffer overflow | |
2179 | * %-EMSGSIZE on overflow of storage buffer @ptr | |
2180 | */ | |
2181 | ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, size_t size) | |
2182 | { | |
2183 | ssize_t ret; | |
2184 | void *p; | |
2185 | ||
2186 | ret = xdr_stream_decode_opaque_inline(xdr, &p, size); | |
2187 | if (ret <= 0) | |
2188 | return ret; | |
2189 | memcpy(ptr, p, ret); | |
2190 | return ret; | |
2191 | } | |
2192 | EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque); | |
2193 | ||
2194 | /** | |
2195 | * xdr_stream_decode_opaque_dup - Decode and duplicate variable length opaque | |
2196 | * @xdr: pointer to xdr_stream | |
2197 | * @ptr: location to store pointer to opaque data | |
2198 | * @maxlen: maximum acceptable object size | |
2199 | * @gfp_flags: GFP mask to use | |
2200 | * | |
2201 | * Return values: | |
2202 | * On success, returns size of object stored in *@ptr | |
2203 | * %-EBADMSG on XDR buffer overflow | |
2204 | * %-EMSGSIZE if the size of the object would exceed @maxlen | |
2205 | * %-ENOMEM on memory allocation failure | |
2206 | */ | |
2207 | ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr, | |
2208 | size_t maxlen, gfp_t gfp_flags) | |
2209 | { | |
2210 | ssize_t ret; | |
2211 | void *p; | |
2212 | ||
2213 | ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen); | |
2214 | if (ret > 0) { | |
2215 | *ptr = kmemdup(p, ret, gfp_flags); | |
2216 | if (*ptr != NULL) | |
2217 | return ret; | |
2218 | ret = -ENOMEM; | |
2219 | } | |
2220 | *ptr = NULL; | |
2221 | return ret; | |
2222 | } | |
2223 | EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque_dup); | |
2224 | ||
2225 | /** | |
2226 | * xdr_stream_decode_string - Decode variable length string | |
2227 | * @xdr: pointer to xdr_stream | |
2228 | * @str: location to store string | |
2229 | * @size: size of storage buffer @str | |
2230 | * | |
2231 | * Return values: | |
2232 | * On success, returns length of NUL-terminated string stored in *@str | |
2233 | * %-EBADMSG on XDR buffer overflow | |
2234 | * %-EMSGSIZE on overflow of storage buffer @str | |
2235 | */ | |
2236 | ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, size_t size) | |
2237 | { | |
2238 | ssize_t ret; | |
2239 | void *p; | |
2240 | ||
2241 | ret = xdr_stream_decode_opaque_inline(xdr, &p, size); | |
2242 | if (ret > 0) { | |
2243 | memcpy(str, p, ret); | |
2244 | str[ret] = '\0'; | |
2245 | return strlen(str); | |
2246 | } | |
2247 | *str = '\0'; | |
2248 | return ret; | |
2249 | } | |
2250 | EXPORT_SYMBOL_GPL(xdr_stream_decode_string); | |
2251 | ||
5c741d4f TM |
2252 | /** |
2253 | * xdr_stream_decode_string_dup - Decode and duplicate variable length string | |
2254 | * @xdr: pointer to xdr_stream | |
2255 | * @str: location to store pointer to string | |
2256 | * @maxlen: maximum acceptable string length | |
2257 | * @gfp_flags: GFP mask to use | |
2258 | * | |
2259 | * Return values: | |
2260 | * On success, returns length of NUL-terminated string stored in *@ptr | |
2261 | * %-EBADMSG on XDR buffer overflow | |
2262 | * %-EMSGSIZE if the size of the string would exceed @maxlen | |
2263 | * %-ENOMEM on memory allocation failure | |
2264 | */ | |
2265 | ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, | |
2266 | size_t maxlen, gfp_t gfp_flags) | |
2267 | { | |
2268 | void *p; | |
2269 | ssize_t ret; | |
2270 | ||
2271 | ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen); | |
2272 | if (ret > 0) { | |
4aceaaea | 2273 | char *s = kmemdup_nul(p, ret, gfp_flags); |
5c741d4f | 2274 | if (s != NULL) { |
5c741d4f TM |
2275 | *str = s; |
2276 | return strlen(s); | |
2277 | } | |
2278 | ret = -ENOMEM; | |
2279 | } | |
2280 | *str = NULL; | |
2281 | return ret; | |
2282 | } | |
2283 | EXPORT_SYMBOL_GPL(xdr_stream_decode_string_dup); | |
846b5756 CL |
2284 | |
2285 | /** | |
2286 | * xdr_stream_decode_opaque_auth - Decode struct opaque_auth (RFC5531 S8.2) | |
2287 | * @xdr: pointer to xdr_stream | |
2288 | * @flavor: location to store decoded flavor | |
2289 | * @body: location to store decode body | |
2290 | * @body_len: location to store length of decoded body | |
2291 | * | |
2292 | * Return values: | |
2293 | * On success, returns the number of buffer bytes consumed | |
2294 | * %-EBADMSG on XDR buffer overflow | |
2295 | * %-EMSGSIZE if the decoded size of the body field exceeds 400 octets | |
2296 | */ | |
2297 | ssize_t xdr_stream_decode_opaque_auth(struct xdr_stream *xdr, u32 *flavor, | |
2298 | void **body, unsigned int *body_len) | |
2299 | { | |
2300 | ssize_t ret, len; | |
2301 | ||
2302 | len = xdr_stream_decode_u32(xdr, flavor); | |
2303 | if (unlikely(len < 0)) | |
2304 | return len; | |
2305 | ret = xdr_stream_decode_opaque_inline(xdr, body, RPC_MAX_AUTH_SIZE); | |
2306 | if (unlikely(ret < 0)) | |
2307 | return ret; | |
2308 | *body_len = ret; | |
2309 | return len + ret; | |
2310 | } | |
2311 | EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque_auth); | |
7b402c8d CL |
2312 | |
2313 | /** | |
2314 | * xdr_stream_encode_opaque_auth - Encode struct opaque_auth (RFC5531 S8.2) | |
2315 | * @xdr: pointer to xdr_stream | |
2316 | * @flavor: verifier flavor to encode | |
2317 | * @body: content of body to encode | |
2318 | * @body_len: length of body to encode | |
2319 | * | |
2320 | * Return values: | |
2321 | * On success, returns length in bytes of XDR buffer consumed | |
2322 | * %-EBADMSG on XDR buffer overflow | |
2323 | * %-EMSGSIZE if the size of @body exceeds 400 octets | |
2324 | */ | |
2325 | ssize_t xdr_stream_encode_opaque_auth(struct xdr_stream *xdr, u32 flavor, | |
2326 | void *body, unsigned int body_len) | |
2327 | { | |
2328 | ssize_t ret, len; | |
2329 | ||
2330 | if (unlikely(body_len > RPC_MAX_AUTH_SIZE)) | |
2331 | return -EMSGSIZE; | |
2332 | len = xdr_stream_encode_u32(xdr, flavor); | |
2333 | if (unlikely(len < 0)) | |
2334 | return len; | |
2335 | ret = xdr_stream_encode_opaque(xdr, body, body_len); | |
2336 | if (unlikely(ret < 0)) | |
2337 | return ret; | |
2338 | return len + ret; | |
2339 | } | |
2340 | EXPORT_SYMBOL_GPL(xdr_stream_encode_opaque_auth); |