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 LT |
21 | |
22 | /* | |
23 | * XDR functions for basic NFS types | |
24 | */ | |
d8ed029d AD |
25 | __be32 * |
26 | xdr_encode_netobj(__be32 *p, const struct xdr_netobj *obj) | |
1da177e4 LT |
27 | { |
28 | unsigned int quadlen = XDR_QUADLEN(obj->len); | |
29 | ||
30 | p[quadlen] = 0; /* zero trailing bytes */ | |
9f162d2a | 31 | *p++ = cpu_to_be32(obj->len); |
1da177e4 LT |
32 | memcpy(p, obj->data, obj->len); |
33 | return p + XDR_QUADLEN(obj->len); | |
34 | } | |
468039ee | 35 | EXPORT_SYMBOL_GPL(xdr_encode_netobj); |
1da177e4 | 36 | |
d8ed029d AD |
37 | __be32 * |
38 | xdr_decode_netobj(__be32 *p, struct xdr_netobj *obj) | |
1da177e4 LT |
39 | { |
40 | unsigned int len; | |
41 | ||
98866b5a | 42 | if ((len = be32_to_cpu(*p++)) > XDR_MAX_NETOBJ) |
1da177e4 LT |
43 | return NULL; |
44 | obj->len = len; | |
45 | obj->data = (u8 *) p; | |
46 | return p + XDR_QUADLEN(len); | |
47 | } | |
468039ee | 48 | EXPORT_SYMBOL_GPL(xdr_decode_netobj); |
1da177e4 LT |
49 | |
50 | /** | |
51 | * xdr_encode_opaque_fixed - Encode fixed length opaque data | |
4dc3b16b PP |
52 | * @p: pointer to current position in XDR buffer. |
53 | * @ptr: pointer to data to encode (or NULL) | |
54 | * @nbytes: size of data. | |
1da177e4 LT |
55 | * |
56 | * Copy the array of data of length nbytes at ptr to the XDR buffer | |
57 | * at position p, then align to the next 32-bit boundary by padding | |
58 | * with zero bytes (see RFC1832). | |
59 | * Note: if ptr is NULL, only the padding is performed. | |
60 | * | |
61 | * Returns the updated current XDR buffer position | |
62 | * | |
63 | */ | |
d8ed029d | 64 | __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int nbytes) |
1da177e4 LT |
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 | } | |
468039ee | 78 | EXPORT_SYMBOL_GPL(xdr_encode_opaque_fixed); |
1da177e4 LT |
79 | |
80 | /** | |
81 | * xdr_encode_opaque - Encode variable length opaque data | |
4dc3b16b PP |
82 | * @p: pointer to current position in XDR buffer. |
83 | * @ptr: pointer to data to encode (or NULL) | |
84 | * @nbytes: size of data. | |
1da177e4 LT |
85 | * |
86 | * Returns the updated current XDR buffer position | |
87 | */ | |
d8ed029d | 88 | __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int nbytes) |
1da177e4 | 89 | { |
9f162d2a | 90 | *p++ = cpu_to_be32(nbytes); |
1da177e4 LT |
91 | return xdr_encode_opaque_fixed(p, ptr, nbytes); |
92 | } | |
468039ee | 93 | EXPORT_SYMBOL_GPL(xdr_encode_opaque); |
1da177e4 | 94 | |
d8ed029d AD |
95 | __be32 * |
96 | xdr_encode_string(__be32 *p, const char *string) | |
1da177e4 LT |
97 | { |
98 | return xdr_encode_array(p, string, strlen(string)); | |
99 | } | |
468039ee | 100 | EXPORT_SYMBOL_GPL(xdr_encode_string); |
1da177e4 | 101 | |
d8ed029d | 102 | __be32 * |
e5cff482 CL |
103 | xdr_decode_string_inplace(__be32 *p, char **sp, |
104 | unsigned int *lenp, unsigned int maxlen) | |
1da177e4 | 105 | { |
e5cff482 | 106 | u32 len; |
1da177e4 | 107 | |
98866b5a | 108 | len = be32_to_cpu(*p++); |
e5cff482 | 109 | if (len > maxlen) |
1da177e4 LT |
110 | return NULL; |
111 | *lenp = len; | |
112 | *sp = (char *) p; | |
113 | return p + XDR_QUADLEN(len); | |
114 | } | |
468039ee | 115 | EXPORT_SYMBOL_GPL(xdr_decode_string_inplace); |
1da177e4 | 116 | |
b4687da7 CL |
117 | /** |
118 | * xdr_terminate_string - '\0'-terminate a string residing in an xdr_buf | |
119 | * @buf: XDR buffer where string resides | |
120 | * @len: length of string, in bytes | |
121 | * | |
122 | */ | |
123 | void | |
124 | xdr_terminate_string(struct xdr_buf *buf, const u32 len) | |
125 | { | |
126 | char *kaddr; | |
127 | ||
b8541786 | 128 | kaddr = kmap_atomic(buf->pages[0]); |
b4687da7 | 129 | kaddr[buf->page_base + len] = '\0'; |
b8541786 | 130 | kunmap_atomic(kaddr); |
b4687da7 | 131 | } |
0d961aa9 | 132 | EXPORT_SYMBOL_GPL(xdr_terminate_string); |
b4687da7 | 133 | |
9d96acbc TM |
134 | size_t |
135 | xdr_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 | ||
142 | int | |
143 | xdr_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 | ||
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; | |
02ef04e4 CL |
193 | if ((xdr->page_len & 3) == 0) |
194 | tail->iov_len -= sizeof(__be32); | |
1da177e4 LT |
195 | |
196 | xdr->buflen += len; | |
197 | } | |
468039ee | 198 | EXPORT_SYMBOL_GPL(xdr_inline_pages); |
1da177e4 | 199 | |
1da177e4 LT |
200 | /* |
201 | * Helper routines for doing 'memmove' like operations on a struct xdr_buf | |
2c53040f BH |
202 | */ |
203 | ||
204 | /** | |
1da177e4 LT |
205 | * _shift_data_right_pages |
206 | * @pages: vector of pages containing both the source and dest memory area. | |
207 | * @pgto_base: page vector address of destination | |
208 | * @pgfrom_base: page vector address of source | |
209 | * @len: number of bytes to copy | |
210 | * | |
211 | * Note: the addresses pgto_base and pgfrom_base are both calculated in | |
212 | * the same way: | |
213 | * if a memory area starts at byte 'base' in page 'pages[i]', | |
ea1754a0 | 214 | * then its address is given as (i << PAGE_SHIFT) + base |
1da177e4 LT |
215 | * Also note: pgfrom_base must be < pgto_base, but the memory areas |
216 | * they point to may overlap. | |
217 | */ | |
218 | static 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 | ||
09cbfeaf KS |
231 | pgto = pages + (pgto_base >> PAGE_SHIFT); |
232 | pgfrom = pages + (pgfrom_base >> PAGE_SHIFT); | |
1da177e4 | 233 | |
09cbfeaf KS |
234 | pgto_base &= ~PAGE_MASK; |
235 | pgfrom_base &= ~PAGE_MASK; | |
1da177e4 LT |
236 | |
237 | do { | |
238 | /* Are any pointers crossing a page boundary? */ | |
239 | if (pgto_base == 0) { | |
09cbfeaf | 240 | pgto_base = PAGE_SIZE; |
1da177e4 LT |
241 | pgto--; |
242 | } | |
243 | if (pgfrom_base == 0) { | |
09cbfeaf | 244 | pgfrom_base = PAGE_SIZE; |
1da177e4 LT |
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 | ||
b8541786 | 256 | vto = kmap_atomic(*pgto); |
347e2233 TM |
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); | |
bce3481c | 263 | flush_dcache_page(*pgto); |
b8541786 | 264 | kunmap_atomic(vto); |
1da177e4 LT |
265 | |
266 | } while ((len -= copy) != 0); | |
1da177e4 LT |
267 | } |
268 | ||
2c53040f | 269 | /** |
1da177e4 LT |
270 | * _copy_to_pages |
271 | * @pages: array of pages | |
272 | * @pgbase: page vector address of destination | |
273 | * @p: pointer to source data | |
274 | * @len: length | |
275 | * | |
276 | * Copies data from an arbitrary memory location into an array of pages | |
277 | * The copy is assumed to be non-overlapping. | |
278 | */ | |
279 | static 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 | ||
09cbfeaf KS |
286 | pgto = pages + (pgbase >> PAGE_SHIFT); |
287 | pgbase &= ~PAGE_MASK; | |
1da177e4 | 288 | |
daeba89d | 289 | for (;;) { |
09cbfeaf | 290 | copy = PAGE_SIZE - pgbase; |
1da177e4 LT |
291 | if (copy > len) |
292 | copy = len; | |
293 | ||
b8541786 | 294 | vto = kmap_atomic(*pgto); |
1da177e4 | 295 | memcpy(vto + pgbase, p, copy); |
b8541786 | 296 | kunmap_atomic(vto); |
1da177e4 | 297 | |
daeba89d TM |
298 | len -= copy; |
299 | if (len == 0) | |
300 | break; | |
301 | ||
1da177e4 | 302 | pgbase += copy; |
09cbfeaf | 303 | if (pgbase == PAGE_SIZE) { |
1da177e4 LT |
304 | flush_dcache_page(*pgto); |
305 | pgbase = 0; | |
306 | pgto++; | |
307 | } | |
308 | p += copy; | |
daeba89d | 309 | } |
1da177e4 LT |
310 | flush_dcache_page(*pgto); |
311 | } | |
312 | ||
2c53040f | 313 | /** |
1da177e4 LT |
314 | * _copy_from_pages |
315 | * @p: pointer to destination | |
316 | * @pages: array of pages | |
317 | * @pgbase: offset of source data | |
318 | * @len: length | |
319 | * | |
320 | * Copies data into an arbitrary memory location from an array of pages | |
321 | * The copy is assumed to be non-overlapping. | |
322 | */ | |
bf118a34 | 323 | void |
1da177e4 LT |
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 | ||
09cbfeaf KS |
330 | pgfrom = pages + (pgbase >> PAGE_SHIFT); |
331 | pgbase &= ~PAGE_MASK; | |
1da177e4 LT |
332 | |
333 | do { | |
09cbfeaf | 334 | copy = PAGE_SIZE - pgbase; |
1da177e4 LT |
335 | if (copy > len) |
336 | copy = len; | |
337 | ||
b8541786 | 338 | vfrom = kmap_atomic(*pgfrom); |
1da177e4 | 339 | memcpy(p, vfrom + pgbase, copy); |
b8541786 | 340 | kunmap_atomic(vfrom); |
1da177e4 LT |
341 | |
342 | pgbase += copy; | |
09cbfeaf | 343 | if (pgbase == PAGE_SIZE) { |
1da177e4 LT |
344 | pgbase = 0; |
345 | pgfrom++; | |
346 | } | |
347 | p += copy; | |
348 | ||
349 | } while ((len -= copy) != 0); | |
350 | } | |
bf118a34 | 351 | EXPORT_SYMBOL_GPL(_copy_from_pages); |
1da177e4 | 352 | |
2c53040f | 353 | /** |
1da177e4 LT |
354 | * xdr_shrink_bufhead |
355 | * @buf: xdr_buf | |
356 | * @len: bytes to remove from buf->head[0] | |
357 | * | |
cca5172a | 358 | * Shrinks XDR buffer's header kvec buf->head[0] by |
1da177e4 LT |
359 | * 'len' bytes. The extra data is not lost, but is instead |
360 | * moved into the inlined pages and/or the tail. | |
361 | */ | |
7be9cea3 | 362 | static unsigned int |
1da177e4 LT |
363 | xdr_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; | |
7be9cea3 | 368 | unsigned int result; |
1da177e4 | 369 | |
7be9cea3 | 370 | result = 0; |
1da177e4 LT |
371 | tail = buf->tail; |
372 | head = buf->head; | |
18e624ad WAA |
373 | |
374 | WARN_ON_ONCE(len > head->iov_len); | |
375 | if (len > head->iov_len) | |
376 | len = head->iov_len; | |
1da177e4 LT |
377 | |
378 | /* Shift the tail first */ | |
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); | |
7be9cea3 | 384 | result += copy; |
1da177e4 LT |
385 | } |
386 | /* Copy from the inlined pages into the tail */ | |
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; | |
7be9cea3 | 395 | if (copy != 0) { |
1da177e4 LT |
396 | _copy_from_pages((char *)tail->iov_base + offs, |
397 | buf->pages, | |
398 | buf->page_base + pglen + offs - len, | |
399 | copy); | |
7be9cea3 CL |
400 | result += copy; |
401 | } | |
1da177e4 LT |
402 | /* Do we also need to copy data from the head into the tail ? */ |
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); | |
7be9cea3 | 411 | result += copy; |
1da177e4 LT |
412 | } |
413 | } | |
414 | /* Now handle pages */ | |
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); | |
7be9cea3 | 427 | result += copy; |
1da177e4 LT |
428 | } |
429 | head->iov_len -= len; | |
430 | buf->buflen -= len; | |
431 | /* Have we truncated the message? */ | |
432 | if (buf->len > buf->buflen) | |
433 | buf->len = buf->buflen; | |
7be9cea3 CL |
434 | |
435 | return result; | |
1da177e4 LT |
436 | } |
437 | ||
2c53040f | 438 | /** |
e8d70b32 | 439 | * xdr_shrink_pagelen - shrinks buf->pages by up to @len bytes |
1da177e4 LT |
440 | * @buf: xdr_buf |
441 | * @len: bytes to remove from buf->pages | |
442 | * | |
e8d70b32 CL |
443 | * The extra data is not lost, but is instead moved into buf->tail. |
444 | * Returns the actual number of bytes moved. | |
1da177e4 | 445 | */ |
7be9cea3 | 446 | static unsigned int |
1da177e4 LT |
447 | xdr_shrink_pagelen(struct xdr_buf *buf, size_t len) |
448 | { | |
449 | struct kvec *tail; | |
450 | size_t copy; | |
1da177e4 | 451 | unsigned int pglen = buf->page_len; |
cf187c2d | 452 | unsigned int tailbuf_len; |
7be9cea3 | 453 | unsigned int result; |
1da177e4 | 454 | |
7be9cea3 | 455 | result = 0; |
1da177e4 | 456 | tail = buf->tail; |
e8d70b32 CL |
457 | if (len > buf->page_len) |
458 | len = buf-> page_len; | |
cf187c2d TM |
459 | tailbuf_len = buf->buflen - buf->head->iov_len - buf->page_len; |
460 | ||
1da177e4 | 461 | /* Shift the tail first */ |
cf187c2d TM |
462 | if (tailbuf_len != 0) { |
463 | unsigned int free_space = tailbuf_len - tail->iov_len; | |
464 | ||
465 | if (len < free_space) | |
466 | free_space = len; | |
467 | tail->iov_len += free_space; | |
468 | ||
42d6d8ab | 469 | copy = len; |
1da177e4 | 470 | if (tail->iov_len > len) { |
0fe62a35 | 471 | char *p = (char *)tail->iov_base + len; |
2e29ebb8 | 472 | memmove(p, tail->iov_base, tail->iov_len - len); |
7be9cea3 | 473 | result += tail->iov_len - len; |
42d6d8ab | 474 | } else |
1da177e4 | 475 | copy = tail->iov_len; |
42d6d8ab | 476 | /* Copy from the inlined pages into the tail */ |
1da177e4 LT |
477 | _copy_from_pages((char *)tail->iov_base, |
478 | buf->pages, buf->page_base + pglen - len, | |
479 | copy); | |
7be9cea3 | 480 | result += copy; |
1da177e4 LT |
481 | } |
482 | buf->page_len -= len; | |
483 | buf->buflen -= len; | |
484 | /* Have we truncated the message? */ | |
485 | if (buf->len > buf->buflen) | |
486 | buf->len = buf->buflen; | |
7be9cea3 CL |
487 | |
488 | return result; | |
1da177e4 LT |
489 | } |
490 | ||
491 | void | |
492 | xdr_shift_buf(struct xdr_buf *buf, size_t len) | |
493 | { | |
494 | xdr_shrink_bufhead(buf, len); | |
495 | } | |
468039ee | 496 | EXPORT_SYMBOL_GPL(xdr_shift_buf); |
1da177e4 | 497 | |
4517d526 TM |
498 | /** |
499 | * xdr_stream_pos - Return the current offset from the start of the xdr_stream | |
500 | * @xdr: pointer to struct xdr_stream | |
501 | */ | |
502 | unsigned int xdr_stream_pos(const struct xdr_stream *xdr) | |
503 | { | |
504 | return (unsigned int)(XDR_QUADLEN(xdr->buf->len) - xdr->nwords) << 2; | |
505 | } | |
506 | EXPORT_SYMBOL_GPL(xdr_stream_pos); | |
507 | ||
1da177e4 LT |
508 | /** |
509 | * xdr_init_encode - Initialize a struct xdr_stream for sending data. | |
510 | * @xdr: pointer to xdr_stream struct | |
511 | * @buf: pointer to XDR buffer in which to encode data | |
512 | * @p: current pointer inside XDR buffer | |
0ccc61b1 | 513 | * @rqst: pointer to controlling rpc_rqst, for debugging |
1da177e4 LT |
514 | * |
515 | * Note: at the moment the RPC client only passes the length of our | |
516 | * scratch buffer in the xdr_buf's header kvec. Previously this | |
517 | * meant we needed to call xdr_adjust_iovec() after encoding the | |
518 | * data. With the new scheme, the xdr_stream manages the details | |
519 | * of the buffer length, and takes care of adjusting the kvec | |
520 | * length for us. | |
521 | */ | |
0ccc61b1 CL |
522 | void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p, |
523 | struct rpc_rqst *rqst) | |
1da177e4 LT |
524 | { |
525 | struct kvec *iov = buf->head; | |
334ccfd5 | 526 | int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len; |
1da177e4 | 527 | |
2825a7f9 | 528 | xdr_set_scratch_buffer(xdr, NULL, 0); |
334ccfd5 | 529 | BUG_ON(scratch_len < 0); |
1da177e4 LT |
530 | xdr->buf = buf; |
531 | xdr->iov = iov; | |
d8ed029d AD |
532 | xdr->p = (__be32 *)((char *)iov->iov_base + iov->iov_len); |
533 | xdr->end = (__be32 *)((char *)iov->iov_base + scratch_len); | |
334ccfd5 TM |
534 | BUG_ON(iov->iov_len > scratch_len); |
535 | ||
536 | if (p != xdr->p && p != NULL) { | |
537 | size_t len; | |
538 | ||
539 | BUG_ON(p < xdr->p || p > xdr->end); | |
540 | len = (char *)p - (char *)xdr->p; | |
541 | xdr->p = p; | |
542 | buf->len += len; | |
543 | iov->iov_len += len; | |
544 | } | |
0ccc61b1 | 545 | xdr->rqst = rqst; |
1da177e4 | 546 | } |
468039ee | 547 | EXPORT_SYMBOL_GPL(xdr_init_encode); |
1da177e4 | 548 | |
2825a7f9 BF |
549 | /** |
550 | * xdr_commit_encode - Ensure all data is written to buffer | |
551 | * @xdr: pointer to xdr_stream | |
552 | * | |
553 | * We handle encoding across page boundaries by giving the caller a | |
554 | * temporary location to write to, then later copying the data into | |
555 | * place; xdr_commit_encode does that copying. | |
556 | * | |
557 | * Normally the caller doesn't need to call this directly, as the | |
558 | * following xdr_reserve_space will do it. But an explicit call may be | |
559 | * required at the end of encoding, or any other time when the xdr_buf | |
560 | * data might be read. | |
561 | */ | |
95bd8304 | 562 | inline void xdr_commit_encode(struct xdr_stream *xdr) |
2825a7f9 BF |
563 | { |
564 | int shift = xdr->scratch.iov_len; | |
565 | void *page; | |
566 | ||
567 | if (shift == 0) | |
568 | return; | |
569 | page = page_address(*xdr->page_ptr); | |
570 | memcpy(xdr->scratch.iov_base, page, shift); | |
571 | memmove(page, page + shift, (void *)xdr->p - page); | |
572 | xdr->scratch.iov_len = 0; | |
573 | } | |
574 | EXPORT_SYMBOL_GPL(xdr_commit_encode); | |
575 | ||
22cb4385 TM |
576 | static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr, |
577 | size_t nbytes) | |
2825a7f9 | 578 | { |
025911a5 | 579 | __be32 *p; |
2825a7f9 BF |
580 | int space_left; |
581 | int frag1bytes, frag2bytes; | |
582 | ||
583 | if (nbytes > PAGE_SIZE) | |
5582863f | 584 | goto out_overflow; /* Bigger buffers require special handling */ |
2825a7f9 | 585 | if (xdr->buf->len + nbytes > xdr->buf->buflen) |
5582863f | 586 | goto out_overflow; /* Sorry, we're totally out of space */ |
2825a7f9 BF |
587 | frag1bytes = (xdr->end - xdr->p) << 2; |
588 | frag2bytes = nbytes - frag1bytes; | |
589 | if (xdr->iov) | |
590 | xdr->iov->iov_len += frag1bytes; | |
05638dc7 | 591 | else |
2825a7f9 | 592 | xdr->buf->page_len += frag1bytes; |
05638dc7 | 593 | xdr->page_ptr++; |
2825a7f9 BF |
594 | xdr->iov = NULL; |
595 | /* | |
596 | * If the last encode didn't end exactly on a page boundary, the | |
597 | * next one will straddle boundaries. Encode into the next | |
598 | * page, then copy it back later in xdr_commit_encode. We use | |
599 | * the "scratch" iov to track any temporarily unused fragment of | |
600 | * space at the end of the previous buffer: | |
601 | */ | |
602 | xdr->scratch.iov_base = xdr->p; | |
603 | xdr->scratch.iov_len = frag1bytes; | |
604 | p = page_address(*xdr->page_ptr); | |
605 | /* | |
606 | * Note this is where the next encode will start after we've | |
607 | * shifted this one back: | |
608 | */ | |
609 | xdr->p = (void *)p + frag2bytes; | |
610 | space_left = xdr->buf->buflen - xdr->buf->len; | |
611 | xdr->end = (void *)p + min_t(int, space_left, PAGE_SIZE); | |
612 | xdr->buf->page_len += frag2bytes; | |
613 | xdr->buf->len += nbytes; | |
614 | return p; | |
5582863f CL |
615 | out_overflow: |
616 | trace_rpc_xdr_overflow(xdr, nbytes); | |
617 | return NULL; | |
2825a7f9 BF |
618 | } |
619 | ||
1da177e4 LT |
620 | /** |
621 | * xdr_reserve_space - Reserve buffer space for sending | |
622 | * @xdr: pointer to xdr_stream | |
623 | * @nbytes: number of bytes to reserve | |
624 | * | |
625 | * Checks that we have enough buffer space to encode 'nbytes' more | |
626 | * bytes of data. If so, update the total xdr_buf length, and | |
627 | * adjust the length of the current kvec. | |
628 | */ | |
d8ed029d | 629 | __be32 * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes) |
1da177e4 | 630 | { |
d8ed029d AD |
631 | __be32 *p = xdr->p; |
632 | __be32 *q; | |
1da177e4 | 633 | |
2825a7f9 | 634 | xdr_commit_encode(xdr); |
1da177e4 LT |
635 | /* align nbytes on the next 32-bit boundary */ |
636 | nbytes += 3; | |
637 | nbytes &= ~3; | |
638 | q = p + (nbytes >> 2); | |
639 | if (unlikely(q > xdr->end || q < p)) | |
2825a7f9 | 640 | return xdr_get_next_encode_buffer(xdr, nbytes); |
1da177e4 | 641 | xdr->p = q; |
2825a7f9 BF |
642 | if (xdr->iov) |
643 | xdr->iov->iov_len += nbytes; | |
644 | else | |
645 | xdr->buf->page_len += nbytes; | |
1da177e4 LT |
646 | xdr->buf->len += nbytes; |
647 | return p; | |
648 | } | |
468039ee | 649 | EXPORT_SYMBOL_GPL(xdr_reserve_space); |
1da177e4 | 650 | |
3e19ce76 BF |
651 | /** |
652 | * xdr_truncate_encode - truncate an encode buffer | |
653 | * @xdr: pointer to xdr_stream | |
654 | * @len: new length of buffer | |
655 | * | |
656 | * Truncates the xdr stream, so that xdr->buf->len == len, | |
657 | * and xdr->p points at offset len from the start of the buffer, and | |
658 | * head, tail, and page lengths are adjusted to correspond. | |
659 | * | |
660 | * If this means moving xdr->p to a different buffer, we assume that | |
661 | * that the end pointer should be set to the end of the current page, | |
662 | * except in the case of the head buffer when we assume the head | |
663 | * buffer's current length represents the end of the available buffer. | |
664 | * | |
665 | * This is *not* safe to use on a buffer that already has inlined page | |
666 | * cache pages (as in a zero-copy server read reply), except for the | |
667 | * simple case of truncating from one position in the tail to another. | |
668 | * | |
669 | */ | |
670 | void xdr_truncate_encode(struct xdr_stream *xdr, size_t len) | |
671 | { | |
672 | struct xdr_buf *buf = xdr->buf; | |
673 | struct kvec *head = buf->head; | |
674 | struct kvec *tail = buf->tail; | |
675 | int fraglen; | |
49a068f8 | 676 | int new; |
3e19ce76 BF |
677 | |
678 | if (len > buf->len) { | |
679 | WARN_ON_ONCE(1); | |
680 | return; | |
681 | } | |
2825a7f9 | 682 | xdr_commit_encode(xdr); |
3e19ce76 BF |
683 | |
684 | fraglen = min_t(int, buf->len - len, tail->iov_len); | |
685 | tail->iov_len -= fraglen; | |
686 | buf->len -= fraglen; | |
ed38c069 | 687 | if (tail->iov_len) { |
3e19ce76 | 688 | xdr->p = tail->iov_base + tail->iov_len; |
280caac0 BF |
689 | WARN_ON_ONCE(!xdr->end); |
690 | WARN_ON_ONCE(!xdr->iov); | |
3e19ce76 BF |
691 | return; |
692 | } | |
693 | WARN_ON_ONCE(fraglen); | |
694 | fraglen = min_t(int, buf->len - len, buf->page_len); | |
695 | buf->page_len -= fraglen; | |
696 | buf->len -= fraglen; | |
697 | ||
698 | new = buf->page_base + buf->page_len; | |
49a068f8 BF |
699 | |
700 | xdr->page_ptr = buf->pages + (new >> PAGE_SHIFT); | |
3e19ce76 | 701 | |
ed38c069 | 702 | if (buf->page_len) { |
3e19ce76 BF |
703 | xdr->p = page_address(*xdr->page_ptr); |
704 | xdr->end = (void *)xdr->p + PAGE_SIZE; | |
705 | xdr->p = (void *)xdr->p + (new % PAGE_SIZE); | |
280caac0 | 706 | WARN_ON_ONCE(xdr->iov); |
3e19ce76 BF |
707 | return; |
708 | } | |
5d7a5bcb | 709 | if (fraglen) |
3e19ce76 BF |
710 | xdr->end = head->iov_base + head->iov_len; |
711 | /* (otherwise assume xdr->end is already set) */ | |
5d7a5bcb | 712 | xdr->page_ptr--; |
3e19ce76 BF |
713 | head->iov_len = len; |
714 | buf->len = len; | |
715 | xdr->p = head->iov_base + head->iov_len; | |
716 | xdr->iov = buf->head; | |
717 | } | |
718 | EXPORT_SYMBOL(xdr_truncate_encode); | |
719 | ||
db3f58a9 BF |
720 | /** |
721 | * xdr_restrict_buflen - decrease available buffer space | |
722 | * @xdr: pointer to xdr_stream | |
723 | * @newbuflen: new maximum number of bytes available | |
724 | * | |
725 | * Adjust our idea of how much space is available in the buffer. | |
726 | * If we've already used too much space in the buffer, returns -1. | |
727 | * If the available space is already smaller than newbuflen, returns 0 | |
728 | * and does nothing. Otherwise, adjusts xdr->buf->buflen to newbuflen | |
729 | * and ensures xdr->end is set at most offset newbuflen from the start | |
730 | * of the buffer. | |
731 | */ | |
732 | int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen) | |
733 | { | |
734 | struct xdr_buf *buf = xdr->buf; | |
735 | int left_in_this_buf = (void *)xdr->end - (void *)xdr->p; | |
736 | int end_offset = buf->len + left_in_this_buf; | |
737 | ||
738 | if (newbuflen < 0 || newbuflen < buf->len) | |
739 | return -1; | |
740 | if (newbuflen > buf->buflen) | |
741 | return 0; | |
742 | if (newbuflen < end_offset) | |
743 | xdr->end = (void *)xdr->end + newbuflen - end_offset; | |
744 | buf->buflen = newbuflen; | |
745 | return 0; | |
746 | } | |
747 | EXPORT_SYMBOL(xdr_restrict_buflen); | |
748 | ||
1da177e4 LT |
749 | /** |
750 | * xdr_write_pages - Insert a list of pages into an XDR buffer for sending | |
751 | * @xdr: pointer to xdr_stream | |
752 | * @pages: list of pages | |
753 | * @base: offset of first byte | |
754 | * @len: length of data in bytes | |
755 | * | |
756 | */ | |
757 | void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base, | |
758 | unsigned int len) | |
759 | { | |
760 | struct xdr_buf *buf = xdr->buf; | |
761 | struct kvec *iov = buf->tail; | |
762 | buf->pages = pages; | |
763 | buf->page_base = base; | |
764 | buf->page_len = len; | |
765 | ||
766 | iov->iov_base = (char *)xdr->p; | |
767 | iov->iov_len = 0; | |
768 | xdr->iov = iov; | |
769 | ||
770 | if (len & 3) { | |
771 | unsigned int pad = 4 - (len & 3); | |
772 | ||
773 | BUG_ON(xdr->p >= xdr->end); | |
774 | iov->iov_base = (char *)xdr->p + (len & 3); | |
775 | iov->iov_len += pad; | |
776 | len += pad; | |
777 | *xdr->p++ = 0; | |
778 | } | |
779 | buf->buflen += len; | |
780 | buf->len += len; | |
781 | } | |
468039ee | 782 | EXPORT_SYMBOL_GPL(xdr_write_pages); |
1da177e4 | 783 | |
6650239a | 784 | static void xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov, |
1537693c | 785 | unsigned int len) |
6650239a TM |
786 | { |
787 | if (len > iov->iov_len) | |
788 | len = iov->iov_len; | |
1537693c | 789 | xdr->p = (__be32*)iov->iov_base; |
6650239a TM |
790 | xdr->end = (__be32*)(iov->iov_base + len); |
791 | xdr->iov = iov; | |
792 | xdr->page_ptr = NULL; | |
793 | } | |
794 | ||
795 | static int xdr_set_page_base(struct xdr_stream *xdr, | |
796 | unsigned int base, unsigned int len) | |
797 | { | |
798 | unsigned int pgnr; | |
799 | unsigned int maxlen; | |
800 | unsigned int pgoff; | |
801 | unsigned int pgend; | |
802 | void *kaddr; | |
803 | ||
804 | maxlen = xdr->buf->page_len; | |
805 | if (base >= maxlen) | |
806 | return -EINVAL; | |
807 | maxlen -= base; | |
808 | if (len > maxlen) | |
809 | len = maxlen; | |
810 | ||
811 | base += xdr->buf->page_base; | |
812 | ||
813 | pgnr = base >> PAGE_SHIFT; | |
814 | xdr->page_ptr = &xdr->buf->pages[pgnr]; | |
815 | kaddr = page_address(*xdr->page_ptr); | |
816 | ||
817 | pgoff = base & ~PAGE_MASK; | |
818 | xdr->p = (__be32*)(kaddr + pgoff); | |
819 | ||
820 | pgend = pgoff + len; | |
821 | if (pgend > PAGE_SIZE) | |
822 | pgend = PAGE_SIZE; | |
823 | xdr->end = (__be32*)(kaddr + pgend); | |
824 | xdr->iov = NULL; | |
825 | return 0; | |
826 | } | |
827 | ||
828 | static void xdr_set_next_page(struct xdr_stream *xdr) | |
829 | { | |
830 | unsigned int newbase; | |
831 | ||
832 | newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT; | |
833 | newbase -= xdr->buf->page_base; | |
834 | ||
835 | if (xdr_set_page_base(xdr, newbase, PAGE_SIZE) < 0) | |
a6cebd41 | 836 | xdr_set_iov(xdr, xdr->buf->tail, xdr->nwords << 2); |
6650239a TM |
837 | } |
838 | ||
839 | static bool xdr_set_next_buffer(struct xdr_stream *xdr) | |
840 | { | |
841 | if (xdr->page_ptr != NULL) | |
842 | xdr_set_next_page(xdr); | |
843 | else if (xdr->iov == xdr->buf->head) { | |
844 | if (xdr_set_page_base(xdr, 0, PAGE_SIZE) < 0) | |
a6cebd41 | 845 | xdr_set_iov(xdr, xdr->buf->tail, xdr->nwords << 2); |
6650239a TM |
846 | } |
847 | return xdr->p != xdr->end; | |
848 | } | |
849 | ||
1da177e4 LT |
850 | /** |
851 | * xdr_init_decode - Initialize an xdr_stream for decoding data. | |
852 | * @xdr: pointer to xdr_stream struct | |
853 | * @buf: pointer to XDR buffer from which to decode data | |
854 | * @p: current pointer inside XDR buffer | |
0ccc61b1 | 855 | * @rqst: pointer to controlling rpc_rqst, for debugging |
1da177e4 | 856 | */ |
0ccc61b1 CL |
857 | void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p, |
858 | struct rpc_rqst *rqst) | |
1da177e4 | 859 | { |
1da177e4 | 860 | xdr->buf = buf; |
6650239a TM |
861 | xdr->scratch.iov_base = NULL; |
862 | xdr->scratch.iov_len = 0; | |
bfeea1dc | 863 | xdr->nwords = XDR_QUADLEN(buf->len); |
6650239a | 864 | if (buf->head[0].iov_len != 0) |
1537693c | 865 | xdr_set_iov(xdr, buf->head, buf->len); |
6650239a TM |
866 | else if (buf->page_len != 0) |
867 | xdr_set_page_base(xdr, 0, buf->len); | |
06ef26a0 BC |
868 | else |
869 | xdr_set_iov(xdr, buf->head, buf->len); | |
bfeea1dc TM |
870 | if (p != NULL && p > xdr->p && xdr->end >= p) { |
871 | xdr->nwords -= p - xdr->p; | |
1537693c | 872 | xdr->p = p; |
bfeea1dc | 873 | } |
0ccc61b1 | 874 | xdr->rqst = rqst; |
1da177e4 | 875 | } |
468039ee | 876 | EXPORT_SYMBOL_GPL(xdr_init_decode); |
1da177e4 | 877 | |
f7da7a12 | 878 | /** |
7ecce75f | 879 | * xdr_init_decode_pages - Initialize an xdr_stream for decoding into pages |
f7da7a12 BH |
880 | * @xdr: pointer to xdr_stream struct |
881 | * @buf: pointer to XDR buffer from which to decode data | |
882 | * @pages: list of pages to decode into | |
883 | * @len: length in bytes of buffer in pages | |
884 | */ | |
885 | void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, | |
886 | struct page **pages, unsigned int len) | |
887 | { | |
888 | memset(buf, 0, sizeof(*buf)); | |
889 | buf->pages = pages; | |
890 | buf->page_len = len; | |
891 | buf->buflen = len; | |
892 | buf->len = len; | |
0ccc61b1 | 893 | xdr_init_decode(xdr, buf, NULL, NULL); |
f7da7a12 BH |
894 | } |
895 | EXPORT_SYMBOL_GPL(xdr_init_decode_pages); | |
896 | ||
6650239a | 897 | static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) |
ba8e452a | 898 | { |
bfeea1dc | 899 | unsigned int nwords = XDR_QUADLEN(nbytes); |
ba8e452a | 900 | __be32 *p = xdr->p; |
bfeea1dc | 901 | __be32 *q = p + nwords; |
ba8e452a | 902 | |
bfeea1dc | 903 | if (unlikely(nwords > xdr->nwords || q > xdr->end || q < p)) |
ba8e452a | 904 | return NULL; |
6650239a | 905 | xdr->p = q; |
bfeea1dc | 906 | xdr->nwords -= nwords; |
ba8e452a TM |
907 | return p; |
908 | } | |
ba8e452a | 909 | |
1da177e4 | 910 | /** |
6650239a TM |
911 | * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data. |
912 | * @xdr: pointer to xdr_stream struct | |
913 | * @buf: pointer to an empty buffer | |
914 | * @buflen: size of 'buf' | |
915 | * | |
916 | * The scratch buffer is used when decoding from an array of pages. | |
917 | * If an xdr_inline_decode() call spans across page boundaries, then | |
918 | * we copy the data into the scratch buffer in order to allow linear | |
919 | * access. | |
920 | */ | |
921 | void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen) | |
922 | { | |
923 | xdr->scratch.iov_base = buf; | |
924 | xdr->scratch.iov_len = buflen; | |
925 | } | |
926 | EXPORT_SYMBOL_GPL(xdr_set_scratch_buffer); | |
927 | ||
928 | static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes) | |
929 | { | |
930 | __be32 *p; | |
ace0e14f | 931 | char *cpdest = xdr->scratch.iov_base; |
6650239a TM |
932 | size_t cplen = (char *)xdr->end - (char *)xdr->p; |
933 | ||
934 | if (nbytes > xdr->scratch.iov_len) | |
5582863f | 935 | goto out_overflow; |
ace0e14f TM |
936 | p = __xdr_inline_decode(xdr, cplen); |
937 | if (p == NULL) | |
938 | return NULL; | |
939 | memcpy(cpdest, p, cplen); | |
5582863f CL |
940 | if (!xdr_set_next_buffer(xdr)) |
941 | goto out_overflow; | |
6650239a TM |
942 | cpdest += cplen; |
943 | nbytes -= cplen; | |
6650239a TM |
944 | p = __xdr_inline_decode(xdr, nbytes); |
945 | if (p == NULL) | |
946 | return NULL; | |
947 | memcpy(cpdest, p, nbytes); | |
948 | return xdr->scratch.iov_base; | |
5582863f CL |
949 | out_overflow: |
950 | trace_rpc_xdr_overflow(xdr, nbytes); | |
951 | return NULL; | |
6650239a TM |
952 | } |
953 | ||
954 | /** | |
955 | * xdr_inline_decode - Retrieve XDR data to decode | |
1da177e4 LT |
956 | * @xdr: pointer to xdr_stream struct |
957 | * @nbytes: number of bytes of data to decode | |
958 | * | |
959 | * Check if the input buffer is long enough to enable us to decode | |
960 | * 'nbytes' more bytes of data starting at the current position. | |
961 | * If so return the current pointer, then update the current | |
962 | * pointer position. | |
963 | */ | |
d8ed029d | 964 | __be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) |
1da177e4 | 965 | { |
6650239a | 966 | __be32 *p; |
1da177e4 | 967 | |
5582863f | 968 | if (unlikely(nbytes == 0)) |
6650239a TM |
969 | return xdr->p; |
970 | if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr)) | |
5582863f | 971 | goto out_overflow; |
6650239a TM |
972 | p = __xdr_inline_decode(xdr, nbytes); |
973 | if (p != NULL) | |
974 | return p; | |
975 | return xdr_copy_to_scratch(xdr, nbytes); | |
5582863f CL |
976 | out_overflow: |
977 | trace_rpc_xdr_overflow(xdr, nbytes); | |
978 | return NULL; | |
1da177e4 | 979 | } |
468039ee | 980 | EXPORT_SYMBOL_GPL(xdr_inline_decode); |
1da177e4 | 981 | |
3994ee6f | 982 | static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len) |
1da177e4 LT |
983 | { |
984 | struct xdr_buf *buf = xdr->buf; | |
985 | struct kvec *iov; | |
bfeea1dc | 986 | unsigned int nwords = XDR_QUADLEN(len); |
b760b313 | 987 | unsigned int cur = xdr_stream_pos(xdr); |
7be9cea3 | 988 | unsigned int copied, offset; |
1da177e4 | 989 | |
bfeea1dc | 990 | if (xdr->nwords == 0) |
c337d365 | 991 | return 0; |
7be9cea3 | 992 | |
1da177e4 | 993 | /* Realign pages to current pointer position */ |
7be9cea3 | 994 | iov = buf->head; |
a11a2bf4 | 995 | if (iov->iov_len > cur) { |
7be9cea3 CL |
996 | offset = iov->iov_len - cur; |
997 | copied = xdr_shrink_bufhead(buf, offset); | |
998 | trace_rpc_xdr_alignment(xdr, offset, copied); | |
a11a2bf4 TM |
999 | xdr->nwords = XDR_QUADLEN(buf->len - cur); |
1000 | } | |
1da177e4 | 1001 | |
a11a2bf4 TM |
1002 | if (nwords > xdr->nwords) { |
1003 | nwords = xdr->nwords; | |
1004 | len = nwords << 2; | |
1005 | } | |
1006 | if (buf->page_len <= len) | |
8a9a8b83 | 1007 | len = buf->page_len; |
a11a2bf4 TM |
1008 | else if (nwords < xdr->nwords) { |
1009 | /* Truncate page data and move it into the tail */ | |
7be9cea3 CL |
1010 | offset = buf->page_len - len; |
1011 | copied = xdr_shrink_pagelen(buf, offset); | |
1012 | trace_rpc_xdr_alignment(xdr, offset, copied); | |
a11a2bf4 TM |
1013 | xdr->nwords = XDR_QUADLEN(buf->len - cur); |
1014 | } | |
3994ee6f TM |
1015 | return len; |
1016 | } | |
bd00f84b | 1017 | |
1da177e4 LT |
1018 | /** |
1019 | * xdr_read_pages - Ensure page-based XDR data to decode is aligned at current pointer position | |
1020 | * @xdr: pointer to xdr_stream struct | |
1021 | * @len: number of bytes of page data | |
1022 | * | |
1023 | * Moves data beyond the current pointer position from the XDR head[] buffer | |
1024 | * into the page list. Any data that lies beyond current position + "len" | |
8b23ea7b | 1025 | * bytes is moved into the XDR tail[]. |
3994ee6f TM |
1026 | * |
1027 | * Returns the number of XDR encoded bytes now contained in the pages | |
1da177e4 | 1028 | */ |
3994ee6f | 1029 | unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len) |
1da177e4 LT |
1030 | { |
1031 | struct xdr_buf *buf = xdr->buf; | |
1032 | struct kvec *iov; | |
3994ee6f | 1033 | unsigned int nwords; |
1da177e4 | 1034 | unsigned int end; |
3994ee6f | 1035 | unsigned int padding; |
1da177e4 | 1036 | |
3994ee6f TM |
1037 | len = xdr_align_pages(xdr, len); |
1038 | if (len == 0) | |
1039 | return 0; | |
1040 | nwords = XDR_QUADLEN(len); | |
bfeea1dc | 1041 | padding = (nwords << 2) - len; |
1da177e4 LT |
1042 | xdr->iov = iov = buf->tail; |
1043 | /* Compute remaining message length. */ | |
bd00f84b TM |
1044 | end = ((xdr->nwords - nwords) << 2) + padding; |
1045 | if (end > iov->iov_len) | |
1046 | end = iov->iov_len; | |
1047 | ||
1da177e4 LT |
1048 | /* |
1049 | * Position current pointer at beginning of tail, and | |
1050 | * set remaining message length. | |
1051 | */ | |
d8ed029d AD |
1052 | xdr->p = (__be32 *)((char *)iov->iov_base + padding); |
1053 | xdr->end = (__be32 *)((char *)iov->iov_base + end); | |
76cacaab | 1054 | xdr->page_ptr = NULL; |
bfeea1dc | 1055 | xdr->nwords = XDR_QUADLEN(end - padding); |
c337d365 | 1056 | return len; |
1da177e4 | 1057 | } |
468039ee | 1058 | EXPORT_SYMBOL_GPL(xdr_read_pages); |
1da177e4 | 1059 | |
8b23ea7b TM |
1060 | /** |
1061 | * xdr_enter_page - decode data from the XDR page | |
1062 | * @xdr: pointer to xdr_stream struct | |
1063 | * @len: number of bytes of page data | |
1064 | * | |
1065 | * Moves data beyond the current pointer position from the XDR head[] buffer | |
1066 | * into the page list. Any data that lies beyond current position + "len" | |
1067 | * bytes is moved into the XDR tail[]. The current pointer is then | |
1068 | * repositioned at the beginning of the first XDR page. | |
1069 | */ | |
1070 | void xdr_enter_page(struct xdr_stream *xdr, unsigned int len) | |
1071 | { | |
f8bb7f08 | 1072 | len = xdr_align_pages(xdr, len); |
8b23ea7b TM |
1073 | /* |
1074 | * Position current pointer at beginning of tail, and | |
1075 | * set remaining message length. | |
1076 | */ | |
f8bb7f08 TM |
1077 | if (len != 0) |
1078 | xdr_set_page_base(xdr, 0, len); | |
8b23ea7b | 1079 | } |
468039ee | 1080 | EXPORT_SYMBOL_GPL(xdr_enter_page); |
8b23ea7b | 1081 | |
c2bd2c0a | 1082 | static const struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0}; |
1da177e4 LT |
1083 | |
1084 | void | |
1085 | xdr_buf_from_iov(struct kvec *iov, struct xdr_buf *buf) | |
1086 | { | |
1087 | buf->head[0] = *iov; | |
1088 | buf->tail[0] = empty_iov; | |
1089 | buf->page_len = 0; | |
1090 | buf->buflen = buf->len = iov->iov_len; | |
1091 | } | |
468039ee | 1092 | EXPORT_SYMBOL_GPL(xdr_buf_from_iov); |
1da177e4 | 1093 | |
de4aee2e BF |
1094 | /** |
1095 | * xdr_buf_subsegment - set subbuf to a portion of buf | |
1096 | * @buf: an xdr buffer | |
1097 | * @subbuf: the result buffer | |
1098 | * @base: beginning of range in bytes | |
1099 | * @len: length of range in bytes | |
1100 | * | |
1101 | * sets @subbuf to an xdr buffer representing the portion of @buf of | |
1102 | * length @len starting at offset @base. | |
1103 | * | |
1104 | * @buf and @subbuf may be pointers to the same struct xdr_buf. | |
1105 | * | |
1106 | * Returns -1 if base of length are out of bounds. | |
1107 | */ | |
1da177e4 LT |
1108 | int |
1109 | xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf, | |
1e78957e | 1110 | unsigned int base, unsigned int len) |
1da177e4 | 1111 | { |
1da177e4 | 1112 | subbuf->buflen = subbuf->len = len; |
1e78957e TM |
1113 | if (base < buf->head[0].iov_len) { |
1114 | subbuf->head[0].iov_base = buf->head[0].iov_base + base; | |
1115 | subbuf->head[0].iov_len = min_t(unsigned int, len, | |
1116 | buf->head[0].iov_len - base); | |
1117 | len -= subbuf->head[0].iov_len; | |
1118 | base = 0; | |
1119 | } else { | |
1e78957e | 1120 | base -= buf->head[0].iov_len; |
de4aee2e | 1121 | subbuf->head[0].iov_len = 0; |
1e78957e | 1122 | } |
1da177e4 LT |
1123 | |
1124 | if (base < buf->page_len) { | |
1e78957e TM |
1125 | subbuf->page_len = min(buf->page_len - base, len); |
1126 | base += buf->page_base; | |
09cbfeaf KS |
1127 | subbuf->page_base = base & ~PAGE_MASK; |
1128 | subbuf->pages = &buf->pages[base >> PAGE_SHIFT]; | |
1da177e4 LT |
1129 | len -= subbuf->page_len; |
1130 | base = 0; | |
1131 | } else { | |
1132 | base -= buf->page_len; | |
1133 | subbuf->page_len = 0; | |
1134 | } | |
1135 | ||
1e78957e TM |
1136 | if (base < buf->tail[0].iov_len) { |
1137 | subbuf->tail[0].iov_base = buf->tail[0].iov_base + base; | |
1138 | subbuf->tail[0].iov_len = min_t(unsigned int, len, | |
1139 | buf->tail[0].iov_len - base); | |
1140 | len -= subbuf->tail[0].iov_len; | |
1141 | base = 0; | |
1142 | } else { | |
1e78957e | 1143 | base -= buf->tail[0].iov_len; |
de4aee2e | 1144 | subbuf->tail[0].iov_len = 0; |
1e78957e TM |
1145 | } |
1146 | ||
1da177e4 LT |
1147 | if (base || len) |
1148 | return -1; | |
1149 | return 0; | |
1150 | } | |
468039ee | 1151 | EXPORT_SYMBOL_GPL(xdr_buf_subsegment); |
1da177e4 | 1152 | |
4e3e43ad | 1153 | static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len) |
1da177e4 | 1154 | { |
1e78957e | 1155 | unsigned int this_len; |
1da177e4 | 1156 | |
4e3e43ad TM |
1157 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); |
1158 | memcpy(obj, subbuf->head[0].iov_base, this_len); | |
1da177e4 LT |
1159 | len -= this_len; |
1160 | obj += this_len; | |
4e3e43ad | 1161 | this_len = min_t(unsigned int, len, subbuf->page_len); |
1da177e4 | 1162 | if (this_len) |
4e3e43ad | 1163 | _copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len); |
1da177e4 LT |
1164 | len -= this_len; |
1165 | obj += this_len; | |
4e3e43ad TM |
1166 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
1167 | memcpy(obj, subbuf->tail[0].iov_base, this_len); | |
1da177e4 LT |
1168 | } |
1169 | ||
bd8100e7 | 1170 | /* obj is assumed to point to allocated memory of size at least len: */ |
4e3e43ad | 1171 | int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len) |
bd8100e7 AG |
1172 | { |
1173 | struct xdr_buf subbuf; | |
bd8100e7 AG |
1174 | int status; |
1175 | ||
1176 | status = xdr_buf_subsegment(buf, &subbuf, base, len); | |
4e3e43ad TM |
1177 | if (status != 0) |
1178 | return status; | |
1179 | __read_bytes_from_xdr_buf(&subbuf, obj, len); | |
1180 | return 0; | |
1181 | } | |
468039ee | 1182 | EXPORT_SYMBOL_GPL(read_bytes_from_xdr_buf); |
4e3e43ad TM |
1183 | |
1184 | static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len) | |
1185 | { | |
1186 | unsigned int this_len; | |
1187 | ||
1188 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); | |
1189 | memcpy(subbuf->head[0].iov_base, obj, this_len); | |
bd8100e7 AG |
1190 | len -= this_len; |
1191 | obj += this_len; | |
4e3e43ad | 1192 | this_len = min_t(unsigned int, len, subbuf->page_len); |
bd8100e7 | 1193 | if (this_len) |
4e3e43ad | 1194 | _copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len); |
bd8100e7 AG |
1195 | len -= this_len; |
1196 | obj += this_len; | |
4e3e43ad TM |
1197 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
1198 | memcpy(subbuf->tail[0].iov_base, obj, this_len); | |
1199 | } | |
1200 | ||
1201 | /* obj is assumed to point to allocated memory of size at least len: */ | |
1202 | int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len) | |
1203 | { | |
1204 | struct xdr_buf subbuf; | |
1205 | int status; | |
1206 | ||
1207 | status = xdr_buf_subsegment(buf, &subbuf, base, len); | |
1208 | if (status != 0) | |
1209 | return status; | |
1210 | __write_bytes_to_xdr_buf(&subbuf, obj, len); | |
1211 | return 0; | |
bd8100e7 | 1212 | } |
c43abaed | 1213 | EXPORT_SYMBOL_GPL(write_bytes_to_xdr_buf); |
bd8100e7 AG |
1214 | |
1215 | int | |
1e78957e | 1216 | xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj) |
1da177e4 | 1217 | { |
d8ed029d | 1218 | __be32 raw; |
1da177e4 LT |
1219 | int status; |
1220 | ||
1221 | status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj)); | |
1222 | if (status) | |
1223 | return status; | |
98866b5a | 1224 | *obj = be32_to_cpu(raw); |
1da177e4 LT |
1225 | return 0; |
1226 | } | |
468039ee | 1227 | EXPORT_SYMBOL_GPL(xdr_decode_word); |
1da177e4 | 1228 | |
bd8100e7 | 1229 | int |
1e78957e | 1230 | xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj) |
bd8100e7 | 1231 | { |
9f162d2a | 1232 | __be32 raw = cpu_to_be32(obj); |
bd8100e7 AG |
1233 | |
1234 | return write_bytes_to_xdr_buf(buf, base, &raw, sizeof(obj)); | |
1235 | } | |
468039ee | 1236 | EXPORT_SYMBOL_GPL(xdr_encode_word); |
bd8100e7 | 1237 | |
bd8100e7 AG |
1238 | /* Returns 0 on success, or else a negative error code. */ |
1239 | static int | |
1240 | xdr_xcode_array2(struct xdr_buf *buf, unsigned int base, | |
1241 | struct xdr_array2_desc *desc, int encode) | |
1242 | { | |
1243 | char *elem = NULL, *c; | |
1244 | unsigned int copied = 0, todo, avail_here; | |
1245 | struct page **ppages = NULL; | |
1246 | int err; | |
1247 | ||
1248 | if (encode) { | |
1249 | if (xdr_encode_word(buf, base, desc->array_len) != 0) | |
1250 | return -EINVAL; | |
1251 | } else { | |
1252 | if (xdr_decode_word(buf, base, &desc->array_len) != 0 || | |
58fcb8df | 1253 | desc->array_len > desc->array_maxlen || |
bd8100e7 AG |
1254 | (unsigned long) base + 4 + desc->array_len * |
1255 | desc->elem_size > buf->len) | |
1256 | return -EINVAL; | |
1257 | } | |
1258 | base += 4; | |
1259 | ||
1260 | if (!desc->xcode) | |
1261 | return 0; | |
1262 | ||
1263 | todo = desc->array_len * desc->elem_size; | |
1264 | ||
1265 | /* process head */ | |
1266 | if (todo && base < buf->head->iov_len) { | |
1267 | c = buf->head->iov_base + base; | |
1268 | avail_here = min_t(unsigned int, todo, | |
1269 | buf->head->iov_len - base); | |
1270 | todo -= avail_here; | |
1271 | ||
1272 | while (avail_here >= desc->elem_size) { | |
1273 | err = desc->xcode(desc, c); | |
1274 | if (err) | |
1275 | goto out; | |
1276 | c += desc->elem_size; | |
1277 | avail_here -= desc->elem_size; | |
1278 | } | |
1279 | if (avail_here) { | |
1280 | if (!elem) { | |
1281 | elem = kmalloc(desc->elem_size, GFP_KERNEL); | |
1282 | err = -ENOMEM; | |
1283 | if (!elem) | |
1284 | goto out; | |
1285 | } | |
1286 | if (encode) { | |
1287 | err = desc->xcode(desc, elem); | |
1288 | if (err) | |
1289 | goto out; | |
1290 | memcpy(c, elem, avail_here); | |
1291 | } else | |
1292 | memcpy(elem, c, avail_here); | |
1293 | copied = avail_here; | |
1294 | } | |
1295 | base = buf->head->iov_len; /* align to start of pages */ | |
1296 | } | |
1297 | ||
1298 | /* process pages array */ | |
1299 | base -= buf->head->iov_len; | |
1300 | if (todo && base < buf->page_len) { | |
1301 | unsigned int avail_page; | |
1302 | ||
1303 | avail_here = min(todo, buf->page_len - base); | |
1304 | todo -= avail_here; | |
1305 | ||
1306 | base += buf->page_base; | |
09cbfeaf KS |
1307 | ppages = buf->pages + (base >> PAGE_SHIFT); |
1308 | base &= ~PAGE_MASK; | |
1309 | avail_page = min_t(unsigned int, PAGE_SIZE - base, | |
bd8100e7 AG |
1310 | avail_here); |
1311 | c = kmap(*ppages) + base; | |
1312 | ||
1313 | while (avail_here) { | |
1314 | avail_here -= avail_page; | |
1315 | if (copied || avail_page < desc->elem_size) { | |
1316 | unsigned int l = min(avail_page, | |
1317 | desc->elem_size - copied); | |
1318 | if (!elem) { | |
1319 | elem = kmalloc(desc->elem_size, | |
1320 | GFP_KERNEL); | |
1321 | err = -ENOMEM; | |
1322 | if (!elem) | |
1323 | goto out; | |
1324 | } | |
1325 | if (encode) { | |
1326 | if (!copied) { | |
1327 | err = desc->xcode(desc, elem); | |
1328 | if (err) | |
1329 | goto out; | |
1330 | } | |
1331 | memcpy(c, elem + copied, l); | |
1332 | copied += l; | |
1333 | if (copied == desc->elem_size) | |
1334 | copied = 0; | |
1335 | } else { | |
1336 | memcpy(elem + copied, c, l); | |
1337 | copied += l; | |
1338 | if (copied == desc->elem_size) { | |
1339 | err = desc->xcode(desc, elem); | |
1340 | if (err) | |
1341 | goto out; | |
1342 | copied = 0; | |
1343 | } | |
1344 | } | |
1345 | avail_page -= l; | |
1346 | c += l; | |
1347 | } | |
1348 | while (avail_page >= desc->elem_size) { | |
1349 | err = desc->xcode(desc, c); | |
1350 | if (err) | |
1351 | goto out; | |
1352 | c += desc->elem_size; | |
1353 | avail_page -= desc->elem_size; | |
1354 | } | |
1355 | if (avail_page) { | |
1356 | unsigned int l = min(avail_page, | |
1357 | desc->elem_size - copied); | |
1358 | if (!elem) { | |
1359 | elem = kmalloc(desc->elem_size, | |
1360 | GFP_KERNEL); | |
1361 | err = -ENOMEM; | |
1362 | if (!elem) | |
1363 | goto out; | |
1364 | } | |
1365 | if (encode) { | |
1366 | if (!copied) { | |
1367 | err = desc->xcode(desc, elem); | |
1368 | if (err) | |
1369 | goto out; | |
1370 | } | |
1371 | memcpy(c, elem + copied, l); | |
1372 | copied += l; | |
1373 | if (copied == desc->elem_size) | |
1374 | copied = 0; | |
1375 | } else { | |
1376 | memcpy(elem + copied, c, l); | |
1377 | copied += l; | |
1378 | if (copied == desc->elem_size) { | |
1379 | err = desc->xcode(desc, elem); | |
1380 | if (err) | |
1381 | goto out; | |
1382 | copied = 0; | |
1383 | } | |
1384 | } | |
1385 | } | |
1386 | if (avail_here) { | |
1387 | kunmap(*ppages); | |
1388 | ppages++; | |
1389 | c = kmap(*ppages); | |
1390 | } | |
1391 | ||
1392 | avail_page = min(avail_here, | |
09cbfeaf | 1393 | (unsigned int) PAGE_SIZE); |
bd8100e7 AG |
1394 | } |
1395 | base = buf->page_len; /* align to start of tail */ | |
1396 | } | |
1397 | ||
1398 | /* process tail */ | |
1399 | base -= buf->page_len; | |
1400 | if (todo) { | |
1401 | c = buf->tail->iov_base + base; | |
1402 | if (copied) { | |
1403 | unsigned int l = desc->elem_size - copied; | |
1404 | ||
1405 | if (encode) | |
1406 | memcpy(c, elem + copied, l); | |
1407 | else { | |
1408 | memcpy(elem + copied, c, l); | |
1409 | err = desc->xcode(desc, elem); | |
1410 | if (err) | |
1411 | goto out; | |
1412 | } | |
1413 | todo -= l; | |
1414 | c += l; | |
1415 | } | |
1416 | while (todo) { | |
1417 | err = desc->xcode(desc, c); | |
1418 | if (err) | |
1419 | goto out; | |
1420 | c += desc->elem_size; | |
1421 | todo -= desc->elem_size; | |
1422 | } | |
1423 | } | |
1424 | err = 0; | |
1425 | ||
1426 | out: | |
a51482bd | 1427 | kfree(elem); |
bd8100e7 AG |
1428 | if (ppages) |
1429 | kunmap(*ppages); | |
1430 | return err; | |
1431 | } | |
1432 | ||
1433 | int | |
1434 | xdr_decode_array2(struct xdr_buf *buf, unsigned int base, | |
1435 | struct xdr_array2_desc *desc) | |
1436 | { | |
1437 | if (base >= buf->len) | |
1438 | return -EINVAL; | |
1439 | ||
1440 | return xdr_xcode_array2(buf, base, desc, 0); | |
1441 | } | |
468039ee | 1442 | EXPORT_SYMBOL_GPL(xdr_decode_array2); |
bd8100e7 AG |
1443 | |
1444 | int | |
1445 | xdr_encode_array2(struct xdr_buf *buf, unsigned int base, | |
1446 | struct xdr_array2_desc *desc) | |
1447 | { | |
1448 | if ((unsigned long) base + 4 + desc->array_len * desc->elem_size > | |
1449 | buf->head->iov_len + buf->page_len + buf->tail->iov_len) | |
1450 | return -EINVAL; | |
1451 | ||
1452 | return xdr_xcode_array2(buf, base, desc, 1); | |
1453 | } | |
468039ee | 1454 | EXPORT_SYMBOL_GPL(xdr_encode_array2); |
37a4e6cb OK |
1455 | |
1456 | int | |
1457 | xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, | |
cca5172a | 1458 | int (*actor)(struct scatterlist *, void *), void *data) |
37a4e6cb OK |
1459 | { |
1460 | int i, ret = 0; | |
95c96174 | 1461 | unsigned int page_len, thislen, page_offset; |
37a4e6cb OK |
1462 | struct scatterlist sg[1]; |
1463 | ||
68e3f5dd HX |
1464 | sg_init_table(sg, 1); |
1465 | ||
37a4e6cb OK |
1466 | if (offset >= buf->head[0].iov_len) { |
1467 | offset -= buf->head[0].iov_len; | |
1468 | } else { | |
1469 | thislen = buf->head[0].iov_len - offset; | |
1470 | if (thislen > len) | |
1471 | thislen = len; | |
1472 | sg_set_buf(sg, buf->head[0].iov_base + offset, thislen); | |
1473 | ret = actor(sg, data); | |
1474 | if (ret) | |
1475 | goto out; | |
1476 | offset = 0; | |
1477 | len -= thislen; | |
1478 | } | |
1479 | if (len == 0) | |
1480 | goto out; | |
1481 | ||
1482 | if (offset >= buf->page_len) { | |
1483 | offset -= buf->page_len; | |
1484 | } else { | |
1485 | page_len = buf->page_len - offset; | |
1486 | if (page_len > len) | |
1487 | page_len = len; | |
1488 | len -= page_len; | |
09cbfeaf KS |
1489 | page_offset = (offset + buf->page_base) & (PAGE_SIZE - 1); |
1490 | i = (offset + buf->page_base) >> PAGE_SHIFT; | |
1491 | thislen = PAGE_SIZE - page_offset; | |
37a4e6cb OK |
1492 | do { |
1493 | if (thislen > page_len) | |
1494 | thislen = page_len; | |
642f1490 | 1495 | sg_set_page(sg, buf->pages[i], thislen, page_offset); |
37a4e6cb OK |
1496 | ret = actor(sg, data); |
1497 | if (ret) | |
1498 | goto out; | |
1499 | page_len -= thislen; | |
1500 | i++; | |
1501 | page_offset = 0; | |
09cbfeaf | 1502 | thislen = PAGE_SIZE; |
37a4e6cb OK |
1503 | } while (page_len != 0); |
1504 | offset = 0; | |
1505 | } | |
1506 | if (len == 0) | |
1507 | goto out; | |
1508 | if (offset < buf->tail[0].iov_len) { | |
1509 | thislen = buf->tail[0].iov_len - offset; | |
1510 | if (thislen > len) | |
1511 | thislen = len; | |
1512 | sg_set_buf(sg, buf->tail[0].iov_base + offset, thislen); | |
1513 | ret = actor(sg, data); | |
1514 | len -= thislen; | |
1515 | } | |
1516 | if (len != 0) | |
1517 | ret = -EINVAL; | |
1518 | out: | |
1519 | return ret; | |
1520 | } | |
468039ee | 1521 | EXPORT_SYMBOL_GPL(xdr_process_buf); |
37a4e6cb | 1522 | |
0e779aa7 TM |
1523 | /** |
1524 | * xdr_stream_decode_opaque - Decode variable length opaque | |
1525 | * @xdr: pointer to xdr_stream | |
1526 | * @ptr: location to store opaque data | |
1527 | * @size: size of storage buffer @ptr | |
1528 | * | |
1529 | * Return values: | |
1530 | * On success, returns size of object stored in *@ptr | |
1531 | * %-EBADMSG on XDR buffer overflow | |
1532 | * %-EMSGSIZE on overflow of storage buffer @ptr | |
1533 | */ | |
1534 | ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, size_t size) | |
1535 | { | |
1536 | ssize_t ret; | |
1537 | void *p; | |
1538 | ||
1539 | ret = xdr_stream_decode_opaque_inline(xdr, &p, size); | |
1540 | if (ret <= 0) | |
1541 | return ret; | |
1542 | memcpy(ptr, p, ret); | |
1543 | return ret; | |
1544 | } | |
1545 | EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque); | |
1546 | ||
1547 | /** | |
1548 | * xdr_stream_decode_opaque_dup - Decode and duplicate variable length opaque | |
1549 | * @xdr: pointer to xdr_stream | |
1550 | * @ptr: location to store pointer to opaque data | |
1551 | * @maxlen: maximum acceptable object size | |
1552 | * @gfp_flags: GFP mask to use | |
1553 | * | |
1554 | * Return values: | |
1555 | * On success, returns size of object stored in *@ptr | |
1556 | * %-EBADMSG on XDR buffer overflow | |
1557 | * %-EMSGSIZE if the size of the object would exceed @maxlen | |
1558 | * %-ENOMEM on memory allocation failure | |
1559 | */ | |
1560 | ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr, | |
1561 | size_t maxlen, gfp_t gfp_flags) | |
1562 | { | |
1563 | ssize_t ret; | |
1564 | void *p; | |
1565 | ||
1566 | ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen); | |
1567 | if (ret > 0) { | |
1568 | *ptr = kmemdup(p, ret, gfp_flags); | |
1569 | if (*ptr != NULL) | |
1570 | return ret; | |
1571 | ret = -ENOMEM; | |
1572 | } | |
1573 | *ptr = NULL; | |
1574 | return ret; | |
1575 | } | |
1576 | EXPORT_SYMBOL_GPL(xdr_stream_decode_opaque_dup); | |
1577 | ||
1578 | /** | |
1579 | * xdr_stream_decode_string - Decode variable length string | |
1580 | * @xdr: pointer to xdr_stream | |
1581 | * @str: location to store string | |
1582 | * @size: size of storage buffer @str | |
1583 | * | |
1584 | * Return values: | |
1585 | * On success, returns length of NUL-terminated string stored in *@str | |
1586 | * %-EBADMSG on XDR buffer overflow | |
1587 | * %-EMSGSIZE on overflow of storage buffer @str | |
1588 | */ | |
1589 | ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, size_t size) | |
1590 | { | |
1591 | ssize_t ret; | |
1592 | void *p; | |
1593 | ||
1594 | ret = xdr_stream_decode_opaque_inline(xdr, &p, size); | |
1595 | if (ret > 0) { | |
1596 | memcpy(str, p, ret); | |
1597 | str[ret] = '\0'; | |
1598 | return strlen(str); | |
1599 | } | |
1600 | *str = '\0'; | |
1601 | return ret; | |
1602 | } | |
1603 | EXPORT_SYMBOL_GPL(xdr_stream_decode_string); | |
1604 | ||
5c741d4f TM |
1605 | /** |
1606 | * xdr_stream_decode_string_dup - Decode and duplicate variable length string | |
1607 | * @xdr: pointer to xdr_stream | |
1608 | * @str: location to store pointer to string | |
1609 | * @maxlen: maximum acceptable string length | |
1610 | * @gfp_flags: GFP mask to use | |
1611 | * | |
1612 | * Return values: | |
1613 | * On success, returns length of NUL-terminated string stored in *@ptr | |
1614 | * %-EBADMSG on XDR buffer overflow | |
1615 | * %-EMSGSIZE if the size of the string would exceed @maxlen | |
1616 | * %-ENOMEM on memory allocation failure | |
1617 | */ | |
1618 | ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, | |
1619 | size_t maxlen, gfp_t gfp_flags) | |
1620 | { | |
1621 | void *p; | |
1622 | ssize_t ret; | |
1623 | ||
1624 | ret = xdr_stream_decode_opaque_inline(xdr, &p, maxlen); | |
1625 | if (ret > 0) { | |
1626 | char *s = kmalloc(ret + 1, gfp_flags); | |
1627 | if (s != NULL) { | |
1628 | memcpy(s, p, ret); | |
1629 | s[ret] = '\0'; | |
1630 | *str = s; | |
1631 | return strlen(s); | |
1632 | } | |
1633 | ret = -ENOMEM; | |
1634 | } | |
1635 | *str = NULL; | |
1636 | return ret; | |
1637 | } | |
1638 | EXPORT_SYMBOL_GPL(xdr_stream_decode_string_dup); |