Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/net/sunrpc/xdr.c |
| 3 | * |
| 4 | * Generic XDR support. |
| 5 | * |
| 6 | * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> |
| 7 | */ |
| 8 | |
Chuck Lever | a246b01 | 2005-08-11 16:25:23 -0400 | [diff] [blame] | 9 | #include <linux/module.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 10 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/types.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/string.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/pagemap.h> |
| 15 | #include <linux/errno.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/sunrpc/xdr.h> |
| 17 | #include <linux/sunrpc/msg_prot.h> |
| 18 | |
| 19 | /* |
| 20 | * XDR functions for basic NFS types |
| 21 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 22 | __be32 * |
| 23 | xdr_encode_netobj(__be32 *p, const struct xdr_netobj *obj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | { |
| 25 | unsigned int quadlen = XDR_QUADLEN(obj->len); |
| 26 | |
| 27 | p[quadlen] = 0; /* zero trailing bytes */ |
Benny Halevy | 9f162d2 | 2009-08-14 17:18:44 +0300 | [diff] [blame] | 28 | *p++ = cpu_to_be32(obj->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | memcpy(p, obj->data, obj->len); |
| 30 | return p + XDR_QUADLEN(obj->len); |
| 31 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 32 | EXPORT_SYMBOL_GPL(xdr_encode_netobj); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 34 | __be32 * |
| 35 | xdr_decode_netobj(__be32 *p, struct xdr_netobj *obj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | { |
| 37 | unsigned int len; |
| 38 | |
Benny Halevy | 98866b5 | 2009-08-14 17:18:49 +0300 | [diff] [blame] | 39 | if ((len = be32_to_cpu(*p++)) > XDR_MAX_NETOBJ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | return NULL; |
| 41 | obj->len = len; |
| 42 | obj->data = (u8 *) p; |
| 43 | return p + XDR_QUADLEN(len); |
| 44 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 45 | EXPORT_SYMBOL_GPL(xdr_decode_netobj); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | |
| 47 | /** |
| 48 | * xdr_encode_opaque_fixed - Encode fixed length opaque data |
Pavel Pisa | 4dc3b16 | 2005-05-01 08:59:25 -0700 | [diff] [blame] | 49 | * @p: pointer to current position in XDR buffer. |
| 50 | * @ptr: pointer to data to encode (or NULL) |
| 51 | * @nbytes: size of data. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | * |
| 53 | * Copy the array of data of length nbytes at ptr to the XDR buffer |
| 54 | * at position p, then align to the next 32-bit boundary by padding |
| 55 | * with zero bytes (see RFC1832). |
| 56 | * Note: if ptr is NULL, only the padding is performed. |
| 57 | * |
| 58 | * Returns the updated current XDR buffer position |
| 59 | * |
| 60 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 61 | __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | { |
| 63 | if (likely(nbytes != 0)) { |
| 64 | unsigned int quadlen = XDR_QUADLEN(nbytes); |
| 65 | unsigned int padding = (quadlen << 2) - nbytes; |
| 66 | |
| 67 | if (ptr != NULL) |
| 68 | memcpy(p, ptr, nbytes); |
| 69 | if (padding != 0) |
| 70 | memset((char *)p + nbytes, 0, padding); |
| 71 | p += quadlen; |
| 72 | } |
| 73 | return p; |
| 74 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 75 | EXPORT_SYMBOL_GPL(xdr_encode_opaque_fixed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | |
| 77 | /** |
| 78 | * xdr_encode_opaque - Encode variable length opaque data |
Pavel Pisa | 4dc3b16 | 2005-05-01 08:59:25 -0700 | [diff] [blame] | 79 | * @p: pointer to current position in XDR buffer. |
| 80 | * @ptr: pointer to data to encode (or NULL) |
| 81 | * @nbytes: size of data. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | * |
| 83 | * Returns the updated current XDR buffer position |
| 84 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 85 | __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | { |
Benny Halevy | 9f162d2 | 2009-08-14 17:18:44 +0300 | [diff] [blame] | 87 | *p++ = cpu_to_be32(nbytes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | return xdr_encode_opaque_fixed(p, ptr, nbytes); |
| 89 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 90 | EXPORT_SYMBOL_GPL(xdr_encode_opaque); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 92 | __be32 * |
| 93 | xdr_encode_string(__be32 *p, const char *string) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | { |
| 95 | return xdr_encode_array(p, string, strlen(string)); |
| 96 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 97 | EXPORT_SYMBOL_GPL(xdr_encode_string); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 99 | __be32 * |
Chuck Lever | e5cff48 | 2007-11-01 16:56:47 -0400 | [diff] [blame] | 100 | xdr_decode_string_inplace(__be32 *p, char **sp, |
| 101 | unsigned int *lenp, unsigned int maxlen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | { |
Chuck Lever | e5cff48 | 2007-11-01 16:56:47 -0400 | [diff] [blame] | 103 | u32 len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | |
Benny Halevy | 98866b5 | 2009-08-14 17:18:49 +0300 | [diff] [blame] | 105 | len = be32_to_cpu(*p++); |
Chuck Lever | e5cff48 | 2007-11-01 16:56:47 -0400 | [diff] [blame] | 106 | if (len > maxlen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | return NULL; |
| 108 | *lenp = len; |
| 109 | *sp = (char *) p; |
| 110 | return p + XDR_QUADLEN(len); |
| 111 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 112 | EXPORT_SYMBOL_GPL(xdr_decode_string_inplace); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | |
Chuck Lever | b4687da | 2010-09-21 16:55:48 -0400 | [diff] [blame] | 114 | /** |
| 115 | * xdr_terminate_string - '\0'-terminate a string residing in an xdr_buf |
| 116 | * @buf: XDR buffer where string resides |
| 117 | * @len: length of string, in bytes |
| 118 | * |
| 119 | */ |
| 120 | void |
| 121 | xdr_terminate_string(struct xdr_buf *buf, const u32 len) |
| 122 | { |
| 123 | char *kaddr; |
| 124 | |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 125 | kaddr = kmap_atomic(buf->pages[0]); |
Chuck Lever | b4687da | 2010-09-21 16:55:48 -0400 | [diff] [blame] | 126 | kaddr[buf->page_base + len] = '\0'; |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 127 | kunmap_atomic(kaddr); |
Chuck Lever | b4687da | 2010-09-21 16:55:48 -0400 | [diff] [blame] | 128 | } |
Trond Myklebust | 0d961aa | 2011-07-13 19:24:15 -0400 | [diff] [blame] | 129 | EXPORT_SYMBOL_GPL(xdr_terminate_string); |
Chuck Lever | b4687da | 2010-09-21 16:55:48 -0400 | [diff] [blame] | 130 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | void |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset, |
| 133 | struct page **pages, unsigned int base, unsigned int len) |
| 134 | { |
| 135 | struct kvec *head = xdr->head; |
| 136 | struct kvec *tail = xdr->tail; |
| 137 | char *buf = (char *)head->iov_base; |
| 138 | unsigned int buflen = head->iov_len; |
| 139 | |
| 140 | head->iov_len = offset; |
| 141 | |
| 142 | xdr->pages = pages; |
| 143 | xdr->page_base = base; |
| 144 | xdr->page_len = len; |
| 145 | |
| 146 | tail->iov_base = buf + offset; |
| 147 | tail->iov_len = buflen - offset; |
| 148 | |
| 149 | xdr->buflen += len; |
| 150 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 151 | EXPORT_SYMBOL_GPL(xdr_inline_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | /* |
| 154 | * Helper routines for doing 'memmove' like operations on a struct xdr_buf |
Ben Hutchings | 2c53040 | 2012-07-10 10:55:09 +0000 | [diff] [blame] | 155 | */ |
| 156 | |
| 157 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | * _shift_data_right_pages |
| 159 | * @pages: vector of pages containing both the source and dest memory area. |
| 160 | * @pgto_base: page vector address of destination |
| 161 | * @pgfrom_base: page vector address of source |
| 162 | * @len: number of bytes to copy |
| 163 | * |
| 164 | * Note: the addresses pgto_base and pgfrom_base are both calculated in |
| 165 | * the same way: |
| 166 | * if a memory area starts at byte 'base' in page 'pages[i]', |
Kirill A. Shutemov | ea1754a | 2016-04-01 15:29:48 +0300 | [diff] [blame] | 167 | * then its address is given as (i << PAGE_SHIFT) + base |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | * Also note: pgfrom_base must be < pgto_base, but the memory areas |
| 169 | * they point to may overlap. |
| 170 | */ |
| 171 | static void |
| 172 | _shift_data_right_pages(struct page **pages, size_t pgto_base, |
| 173 | size_t pgfrom_base, size_t len) |
| 174 | { |
| 175 | struct page **pgfrom, **pgto; |
| 176 | char *vfrom, *vto; |
| 177 | size_t copy; |
| 178 | |
| 179 | BUG_ON(pgto_base <= pgfrom_base); |
| 180 | |
| 181 | pgto_base += len; |
| 182 | pgfrom_base += len; |
| 183 | |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 184 | pgto = pages + (pgto_base >> PAGE_SHIFT); |
| 185 | pgfrom = pages + (pgfrom_base >> PAGE_SHIFT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 186 | |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 187 | pgto_base &= ~PAGE_MASK; |
| 188 | pgfrom_base &= ~PAGE_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | |
| 190 | do { |
| 191 | /* Are any pointers crossing a page boundary? */ |
| 192 | if (pgto_base == 0) { |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 193 | pgto_base = PAGE_SIZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | pgto--; |
| 195 | } |
| 196 | if (pgfrom_base == 0) { |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 197 | pgfrom_base = PAGE_SIZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | pgfrom--; |
| 199 | } |
| 200 | |
| 201 | copy = len; |
| 202 | if (copy > pgto_base) |
| 203 | copy = pgto_base; |
| 204 | if (copy > pgfrom_base) |
| 205 | copy = pgfrom_base; |
| 206 | pgto_base -= copy; |
| 207 | pgfrom_base -= copy; |
| 208 | |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 209 | vto = kmap_atomic(*pgto); |
Trond Myklebust | 347e223 | 2013-08-28 13:35:13 -0400 | [diff] [blame] | 210 | if (*pgto != *pgfrom) { |
| 211 | vfrom = kmap_atomic(*pgfrom); |
| 212 | memcpy(vto + pgto_base, vfrom + pgfrom_base, copy); |
| 213 | kunmap_atomic(vfrom); |
| 214 | } else |
| 215 | memmove(vto + pgto_base, vto + pgfrom_base, copy); |
Trond Myklebust | bce3481 | 2006-07-05 13:17:12 -0400 | [diff] [blame] | 216 | flush_dcache_page(*pgto); |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 217 | kunmap_atomic(vto); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | |
| 219 | } while ((len -= copy) != 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | } |
| 221 | |
Ben Hutchings | 2c53040 | 2012-07-10 10:55:09 +0000 | [diff] [blame] | 222 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | * _copy_to_pages |
| 224 | * @pages: array of pages |
| 225 | * @pgbase: page vector address of destination |
| 226 | * @p: pointer to source data |
| 227 | * @len: length |
| 228 | * |
| 229 | * Copies data from an arbitrary memory location into an array of pages |
| 230 | * The copy is assumed to be non-overlapping. |
| 231 | */ |
| 232 | static void |
| 233 | _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len) |
| 234 | { |
| 235 | struct page **pgto; |
| 236 | char *vto; |
| 237 | size_t copy; |
| 238 | |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 239 | pgto = pages + (pgbase >> PAGE_SHIFT); |
| 240 | pgbase &= ~PAGE_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | |
Trond Myklebust | daeba89 | 2008-03-31 17:02:02 -0400 | [diff] [blame] | 242 | for (;;) { |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 243 | copy = PAGE_SIZE - pgbase; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | if (copy > len) |
| 245 | copy = len; |
| 246 | |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 247 | vto = kmap_atomic(*pgto); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | memcpy(vto + pgbase, p, copy); |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 249 | kunmap_atomic(vto); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | |
Trond Myklebust | daeba89 | 2008-03-31 17:02:02 -0400 | [diff] [blame] | 251 | len -= copy; |
| 252 | if (len == 0) |
| 253 | break; |
| 254 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | pgbase += copy; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 256 | if (pgbase == PAGE_SIZE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | flush_dcache_page(*pgto); |
| 258 | pgbase = 0; |
| 259 | pgto++; |
| 260 | } |
| 261 | p += copy; |
Trond Myklebust | daeba89 | 2008-03-31 17:02:02 -0400 | [diff] [blame] | 262 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | flush_dcache_page(*pgto); |
| 264 | } |
| 265 | |
Ben Hutchings | 2c53040 | 2012-07-10 10:55:09 +0000 | [diff] [blame] | 266 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | * _copy_from_pages |
| 268 | * @p: pointer to destination |
| 269 | * @pages: array of pages |
| 270 | * @pgbase: offset of source data |
| 271 | * @len: length |
| 272 | * |
| 273 | * Copies data into an arbitrary memory location from an array of pages |
| 274 | * The copy is assumed to be non-overlapping. |
| 275 | */ |
Andy Adamson | bf118a3 | 2011-12-07 11:55:27 -0500 | [diff] [blame] | 276 | void |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len) |
| 278 | { |
| 279 | struct page **pgfrom; |
| 280 | char *vfrom; |
| 281 | size_t copy; |
| 282 | |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 283 | pgfrom = pages + (pgbase >> PAGE_SHIFT); |
| 284 | pgbase &= ~PAGE_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | |
| 286 | do { |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 287 | copy = PAGE_SIZE - pgbase; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | if (copy > len) |
| 289 | copy = len; |
| 290 | |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 291 | vfrom = kmap_atomic(*pgfrom); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | memcpy(p, vfrom + pgbase, copy); |
Cong Wang | b854178 | 2011-11-25 23:14:40 +0800 | [diff] [blame] | 293 | kunmap_atomic(vfrom); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | |
| 295 | pgbase += copy; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 296 | if (pgbase == PAGE_SIZE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | pgbase = 0; |
| 298 | pgfrom++; |
| 299 | } |
| 300 | p += copy; |
| 301 | |
| 302 | } while ((len -= copy) != 0); |
| 303 | } |
Andy Adamson | bf118a3 | 2011-12-07 11:55:27 -0500 | [diff] [blame] | 304 | EXPORT_SYMBOL_GPL(_copy_from_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | |
Ben Hutchings | 2c53040 | 2012-07-10 10:55:09 +0000 | [diff] [blame] | 306 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | * xdr_shrink_bufhead |
| 308 | * @buf: xdr_buf |
| 309 | * @len: bytes to remove from buf->head[0] |
| 310 | * |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 311 | * Shrinks XDR buffer's header kvec buf->head[0] by |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | * 'len' bytes. The extra data is not lost, but is instead |
| 313 | * moved into the inlined pages and/or the tail. |
| 314 | */ |
| 315 | static void |
| 316 | xdr_shrink_bufhead(struct xdr_buf *buf, size_t len) |
| 317 | { |
| 318 | struct kvec *head, *tail; |
| 319 | size_t copy, offs; |
| 320 | unsigned int pglen = buf->page_len; |
| 321 | |
| 322 | tail = buf->tail; |
| 323 | head = buf->head; |
Weston Andros Adamson | 18e624a | 2012-10-23 10:43:42 -0400 | [diff] [blame] | 324 | |
| 325 | WARN_ON_ONCE(len > head->iov_len); |
| 326 | if (len > head->iov_len) |
| 327 | len = head->iov_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 328 | |
| 329 | /* Shift the tail first */ |
| 330 | if (tail->iov_len != 0) { |
| 331 | if (tail->iov_len > len) { |
| 332 | copy = tail->iov_len - len; |
| 333 | memmove((char *)tail->iov_base + len, |
| 334 | tail->iov_base, copy); |
| 335 | } |
| 336 | /* Copy from the inlined pages into the tail */ |
| 337 | copy = len; |
| 338 | if (copy > pglen) |
| 339 | copy = pglen; |
| 340 | offs = len - copy; |
| 341 | if (offs >= tail->iov_len) |
| 342 | copy = 0; |
| 343 | else if (copy > tail->iov_len - offs) |
| 344 | copy = tail->iov_len - offs; |
| 345 | if (copy != 0) |
| 346 | _copy_from_pages((char *)tail->iov_base + offs, |
| 347 | buf->pages, |
| 348 | buf->page_base + pglen + offs - len, |
| 349 | copy); |
| 350 | /* Do we also need to copy data from the head into the tail ? */ |
| 351 | if (len > pglen) { |
| 352 | offs = copy = len - pglen; |
| 353 | if (copy > tail->iov_len) |
| 354 | copy = tail->iov_len; |
| 355 | memcpy(tail->iov_base, |
| 356 | (char *)head->iov_base + |
| 357 | head->iov_len - offs, |
| 358 | copy); |
| 359 | } |
| 360 | } |
| 361 | /* Now handle pages */ |
| 362 | if (pglen != 0) { |
| 363 | if (pglen > len) |
| 364 | _shift_data_right_pages(buf->pages, |
| 365 | buf->page_base + len, |
| 366 | buf->page_base, |
| 367 | pglen - len); |
| 368 | copy = len; |
| 369 | if (len > pglen) |
| 370 | copy = pglen; |
| 371 | _copy_to_pages(buf->pages, buf->page_base, |
| 372 | (char *)head->iov_base + head->iov_len - len, |
| 373 | copy); |
| 374 | } |
| 375 | head->iov_len -= len; |
| 376 | buf->buflen -= len; |
| 377 | /* Have we truncated the message? */ |
| 378 | if (buf->len > buf->buflen) |
| 379 | buf->len = buf->buflen; |
| 380 | } |
| 381 | |
Ben Hutchings | 2c53040 | 2012-07-10 10:55:09 +0000 | [diff] [blame] | 382 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | * xdr_shrink_pagelen |
| 384 | * @buf: xdr_buf |
| 385 | * @len: bytes to remove from buf->pages |
| 386 | * |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 387 | * Shrinks XDR buffer's page array buf->pages by |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | * 'len' bytes. The extra data is not lost, but is instead |
| 389 | * moved into the tail. |
| 390 | */ |
| 391 | static void |
| 392 | xdr_shrink_pagelen(struct xdr_buf *buf, size_t len) |
| 393 | { |
| 394 | struct kvec *tail; |
| 395 | size_t copy; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | unsigned int pglen = buf->page_len; |
Trond Myklebust | cf187c2 | 2010-08-29 12:13:16 -0400 | [diff] [blame] | 397 | unsigned int tailbuf_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | |
| 399 | tail = buf->tail; |
| 400 | BUG_ON (len > pglen); |
| 401 | |
Trond Myklebust | cf187c2 | 2010-08-29 12:13:16 -0400 | [diff] [blame] | 402 | tailbuf_len = buf->buflen - buf->head->iov_len - buf->page_len; |
| 403 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | /* Shift the tail first */ |
Trond Myklebust | cf187c2 | 2010-08-29 12:13:16 -0400 | [diff] [blame] | 405 | if (tailbuf_len != 0) { |
| 406 | unsigned int free_space = tailbuf_len - tail->iov_len; |
| 407 | |
| 408 | if (len < free_space) |
| 409 | free_space = len; |
| 410 | tail->iov_len += free_space; |
| 411 | |
Benny Halevy | 42d6d8a | 2010-08-29 12:13:15 -0400 | [diff] [blame] | 412 | copy = len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | if (tail->iov_len > len) { |
Benny Halevy | 0fe62a35 | 2010-08-29 12:13:15 -0400 | [diff] [blame] | 414 | char *p = (char *)tail->iov_base + len; |
Benny Halevy | 2e29ebb | 2010-08-29 12:13:15 -0400 | [diff] [blame] | 415 | memmove(p, tail->iov_base, tail->iov_len - len); |
Benny Halevy | 42d6d8a | 2010-08-29 12:13:15 -0400 | [diff] [blame] | 416 | } else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | copy = tail->iov_len; |
Benny Halevy | 42d6d8a | 2010-08-29 12:13:15 -0400 | [diff] [blame] | 418 | /* Copy from the inlined pages into the tail */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | _copy_from_pages((char *)tail->iov_base, |
| 420 | buf->pages, buf->page_base + pglen - len, |
| 421 | copy); |
| 422 | } |
| 423 | buf->page_len -= len; |
| 424 | buf->buflen -= len; |
| 425 | /* Have we truncated the message? */ |
| 426 | if (buf->len > buf->buflen) |
| 427 | buf->len = buf->buflen; |
| 428 | } |
| 429 | |
| 430 | void |
| 431 | xdr_shift_buf(struct xdr_buf *buf, size_t len) |
| 432 | { |
| 433 | xdr_shrink_bufhead(buf, len); |
| 434 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 435 | EXPORT_SYMBOL_GPL(xdr_shift_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | |
| 437 | /** |
Trond Myklebust | 4517d52 | 2012-06-21 17:14:46 -0400 | [diff] [blame] | 438 | * xdr_stream_pos - Return the current offset from the start of the xdr_stream |
| 439 | * @xdr: pointer to struct xdr_stream |
| 440 | */ |
| 441 | unsigned int xdr_stream_pos(const struct xdr_stream *xdr) |
| 442 | { |
| 443 | return (unsigned int)(XDR_QUADLEN(xdr->buf->len) - xdr->nwords) << 2; |
| 444 | } |
| 445 | EXPORT_SYMBOL_GPL(xdr_stream_pos); |
| 446 | |
| 447 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | * xdr_init_encode - Initialize a struct xdr_stream for sending data. |
| 449 | * @xdr: pointer to xdr_stream struct |
| 450 | * @buf: pointer to XDR buffer in which to encode data |
| 451 | * @p: current pointer inside XDR buffer |
| 452 | * |
| 453 | * Note: at the moment the RPC client only passes the length of our |
| 454 | * scratch buffer in the xdr_buf's header kvec. Previously this |
| 455 | * meant we needed to call xdr_adjust_iovec() after encoding the |
| 456 | * data. With the new scheme, the xdr_stream manages the details |
| 457 | * of the buffer length, and takes care of adjusting the kvec |
| 458 | * length for us. |
| 459 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 460 | void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | { |
| 462 | struct kvec *iov = buf->head; |
Trond Myklebust | 334ccfd | 2005-06-22 17:16:19 +0000 | [diff] [blame] | 463 | int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 465 | xdr_set_scratch_buffer(xdr, NULL, 0); |
Trond Myklebust | 334ccfd | 2005-06-22 17:16:19 +0000 | [diff] [blame] | 466 | BUG_ON(scratch_len < 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | xdr->buf = buf; |
| 468 | xdr->iov = iov; |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 469 | xdr->p = (__be32 *)((char *)iov->iov_base + iov->iov_len); |
| 470 | xdr->end = (__be32 *)((char *)iov->iov_base + scratch_len); |
Trond Myklebust | 334ccfd | 2005-06-22 17:16:19 +0000 | [diff] [blame] | 471 | BUG_ON(iov->iov_len > scratch_len); |
| 472 | |
| 473 | if (p != xdr->p && p != NULL) { |
| 474 | size_t len; |
| 475 | |
| 476 | BUG_ON(p < xdr->p || p > xdr->end); |
| 477 | len = (char *)p - (char *)xdr->p; |
| 478 | xdr->p = p; |
| 479 | buf->len += len; |
| 480 | iov->iov_len += len; |
| 481 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 483 | EXPORT_SYMBOL_GPL(xdr_init_encode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | |
| 485 | /** |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 486 | * xdr_commit_encode - Ensure all data is written to buffer |
| 487 | * @xdr: pointer to xdr_stream |
| 488 | * |
| 489 | * We handle encoding across page boundaries by giving the caller a |
| 490 | * temporary location to write to, then later copying the data into |
| 491 | * place; xdr_commit_encode does that copying. |
| 492 | * |
| 493 | * Normally the caller doesn't need to call this directly, as the |
| 494 | * following xdr_reserve_space will do it. But an explicit call may be |
| 495 | * required at the end of encoding, or any other time when the xdr_buf |
| 496 | * data might be read. |
| 497 | */ |
| 498 | void xdr_commit_encode(struct xdr_stream *xdr) |
| 499 | { |
| 500 | int shift = xdr->scratch.iov_len; |
| 501 | void *page; |
| 502 | |
| 503 | if (shift == 0) |
| 504 | return; |
| 505 | page = page_address(*xdr->page_ptr); |
| 506 | memcpy(xdr->scratch.iov_base, page, shift); |
| 507 | memmove(page, page + shift, (void *)xdr->p - page); |
| 508 | xdr->scratch.iov_len = 0; |
| 509 | } |
| 510 | EXPORT_SYMBOL_GPL(xdr_commit_encode); |
| 511 | |
Trond Myklebust | 22cb438 | 2014-07-12 18:01:02 -0400 | [diff] [blame] | 512 | static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr, |
| 513 | size_t nbytes) |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 514 | { |
| 515 | static __be32 *p; |
| 516 | int space_left; |
| 517 | int frag1bytes, frag2bytes; |
| 518 | |
| 519 | if (nbytes > PAGE_SIZE) |
| 520 | return NULL; /* Bigger buffers require special handling */ |
| 521 | if (xdr->buf->len + nbytes > xdr->buf->buflen) |
| 522 | return NULL; /* Sorry, we're totally out of space */ |
| 523 | frag1bytes = (xdr->end - xdr->p) << 2; |
| 524 | frag2bytes = nbytes - frag1bytes; |
| 525 | if (xdr->iov) |
| 526 | xdr->iov->iov_len += frag1bytes; |
J. Bruce Fields | 05638dc | 2014-06-02 12:05:47 -0400 | [diff] [blame] | 527 | else |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 528 | xdr->buf->page_len += frag1bytes; |
J. Bruce Fields | 05638dc | 2014-06-02 12:05:47 -0400 | [diff] [blame] | 529 | xdr->page_ptr++; |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 530 | xdr->iov = NULL; |
| 531 | /* |
| 532 | * If the last encode didn't end exactly on a page boundary, the |
| 533 | * next one will straddle boundaries. Encode into the next |
| 534 | * page, then copy it back later in xdr_commit_encode. We use |
| 535 | * the "scratch" iov to track any temporarily unused fragment of |
| 536 | * space at the end of the previous buffer: |
| 537 | */ |
| 538 | xdr->scratch.iov_base = xdr->p; |
| 539 | xdr->scratch.iov_len = frag1bytes; |
| 540 | p = page_address(*xdr->page_ptr); |
| 541 | /* |
| 542 | * Note this is where the next encode will start after we've |
| 543 | * shifted this one back: |
| 544 | */ |
| 545 | xdr->p = (void *)p + frag2bytes; |
| 546 | space_left = xdr->buf->buflen - xdr->buf->len; |
| 547 | xdr->end = (void *)p + min_t(int, space_left, PAGE_SIZE); |
| 548 | xdr->buf->page_len += frag2bytes; |
| 549 | xdr->buf->len += nbytes; |
| 550 | return p; |
| 551 | } |
| 552 | |
| 553 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | * xdr_reserve_space - Reserve buffer space for sending |
| 555 | * @xdr: pointer to xdr_stream |
| 556 | * @nbytes: number of bytes to reserve |
| 557 | * |
| 558 | * Checks that we have enough buffer space to encode 'nbytes' more |
| 559 | * bytes of data. If so, update the total xdr_buf length, and |
| 560 | * adjust the length of the current kvec. |
| 561 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 562 | __be32 * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | { |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 564 | __be32 *p = xdr->p; |
| 565 | __be32 *q; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 567 | xdr_commit_encode(xdr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | /* align nbytes on the next 32-bit boundary */ |
| 569 | nbytes += 3; |
| 570 | nbytes &= ~3; |
| 571 | q = p + (nbytes >> 2); |
| 572 | if (unlikely(q > xdr->end || q < p)) |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 573 | return xdr_get_next_encode_buffer(xdr, nbytes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | xdr->p = q; |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 575 | if (xdr->iov) |
| 576 | xdr->iov->iov_len += nbytes; |
| 577 | else |
| 578 | xdr->buf->page_len += nbytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 579 | xdr->buf->len += nbytes; |
| 580 | return p; |
| 581 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 582 | EXPORT_SYMBOL_GPL(xdr_reserve_space); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | |
| 584 | /** |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 585 | * xdr_truncate_encode - truncate an encode buffer |
| 586 | * @xdr: pointer to xdr_stream |
| 587 | * @len: new length of buffer |
| 588 | * |
| 589 | * Truncates the xdr stream, so that xdr->buf->len == len, |
| 590 | * and xdr->p points at offset len from the start of the buffer, and |
| 591 | * head, tail, and page lengths are adjusted to correspond. |
| 592 | * |
| 593 | * If this means moving xdr->p to a different buffer, we assume that |
| 594 | * that the end pointer should be set to the end of the current page, |
| 595 | * except in the case of the head buffer when we assume the head |
| 596 | * buffer's current length represents the end of the available buffer. |
| 597 | * |
| 598 | * This is *not* safe to use on a buffer that already has inlined page |
| 599 | * cache pages (as in a zero-copy server read reply), except for the |
| 600 | * simple case of truncating from one position in the tail to another. |
| 601 | * |
| 602 | */ |
| 603 | void xdr_truncate_encode(struct xdr_stream *xdr, size_t len) |
| 604 | { |
| 605 | struct xdr_buf *buf = xdr->buf; |
| 606 | struct kvec *head = buf->head; |
| 607 | struct kvec *tail = buf->tail; |
| 608 | int fraglen; |
J. Bruce Fields | 49a068f | 2014-12-22 16:14:51 -0500 | [diff] [blame] | 609 | int new; |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 610 | |
| 611 | if (len > buf->len) { |
| 612 | WARN_ON_ONCE(1); |
| 613 | return; |
| 614 | } |
J. Bruce Fields | 2825a7f | 2013-08-26 16:04:46 -0400 | [diff] [blame] | 615 | xdr_commit_encode(xdr); |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 616 | |
| 617 | fraglen = min_t(int, buf->len - len, tail->iov_len); |
| 618 | tail->iov_len -= fraglen; |
| 619 | buf->len -= fraglen; |
J. Bruce Fields | ed38c06 | 2014-09-19 17:21:35 -0400 | [diff] [blame] | 620 | if (tail->iov_len) { |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 621 | xdr->p = tail->iov_base + tail->iov_len; |
J. Bruce Fields | 280caac | 2014-10-01 11:36:31 -0400 | [diff] [blame] | 622 | WARN_ON_ONCE(!xdr->end); |
| 623 | WARN_ON_ONCE(!xdr->iov); |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 624 | return; |
| 625 | } |
| 626 | WARN_ON_ONCE(fraglen); |
| 627 | fraglen = min_t(int, buf->len - len, buf->page_len); |
| 628 | buf->page_len -= fraglen; |
| 629 | buf->len -= fraglen; |
| 630 | |
| 631 | new = buf->page_base + buf->page_len; |
J. Bruce Fields | 49a068f | 2014-12-22 16:14:51 -0500 | [diff] [blame] | 632 | |
| 633 | xdr->page_ptr = buf->pages + (new >> PAGE_SHIFT); |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 634 | |
J. Bruce Fields | ed38c06 | 2014-09-19 17:21:35 -0400 | [diff] [blame] | 635 | if (buf->page_len) { |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 636 | xdr->p = page_address(*xdr->page_ptr); |
| 637 | xdr->end = (void *)xdr->p + PAGE_SIZE; |
| 638 | xdr->p = (void *)xdr->p + (new % PAGE_SIZE); |
J. Bruce Fields | 280caac | 2014-10-01 11:36:31 -0400 | [diff] [blame] | 639 | WARN_ON_ONCE(xdr->iov); |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 640 | return; |
| 641 | } |
J. Bruce Fields | 05638dc | 2014-06-02 12:05:47 -0400 | [diff] [blame] | 642 | if (fraglen) { |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 643 | xdr->end = head->iov_base + head->iov_len; |
J. Bruce Fields | 05638dc | 2014-06-02 12:05:47 -0400 | [diff] [blame] | 644 | xdr->page_ptr--; |
| 645 | } |
J. Bruce Fields | 3e19ce7 | 2014-02-25 17:44:21 -0500 | [diff] [blame] | 646 | /* (otherwise assume xdr->end is already set) */ |
| 647 | head->iov_len = len; |
| 648 | buf->len = len; |
| 649 | xdr->p = head->iov_base + head->iov_len; |
| 650 | xdr->iov = buf->head; |
| 651 | } |
| 652 | EXPORT_SYMBOL(xdr_truncate_encode); |
| 653 | |
| 654 | /** |
J. Bruce Fields | db3f58a | 2014-03-06 13:22:18 -0500 | [diff] [blame] | 655 | * xdr_restrict_buflen - decrease available buffer space |
| 656 | * @xdr: pointer to xdr_stream |
| 657 | * @newbuflen: new maximum number of bytes available |
| 658 | * |
| 659 | * Adjust our idea of how much space is available in the buffer. |
| 660 | * If we've already used too much space in the buffer, returns -1. |
| 661 | * If the available space is already smaller than newbuflen, returns 0 |
| 662 | * and does nothing. Otherwise, adjusts xdr->buf->buflen to newbuflen |
| 663 | * and ensures xdr->end is set at most offset newbuflen from the start |
| 664 | * of the buffer. |
| 665 | */ |
| 666 | int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen) |
| 667 | { |
| 668 | struct xdr_buf *buf = xdr->buf; |
| 669 | int left_in_this_buf = (void *)xdr->end - (void *)xdr->p; |
| 670 | int end_offset = buf->len + left_in_this_buf; |
| 671 | |
| 672 | if (newbuflen < 0 || newbuflen < buf->len) |
| 673 | return -1; |
| 674 | if (newbuflen > buf->buflen) |
| 675 | return 0; |
| 676 | if (newbuflen < end_offset) |
| 677 | xdr->end = (void *)xdr->end + newbuflen - end_offset; |
| 678 | buf->buflen = newbuflen; |
| 679 | return 0; |
| 680 | } |
| 681 | EXPORT_SYMBOL(xdr_restrict_buflen); |
| 682 | |
| 683 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 684 | * xdr_write_pages - Insert a list of pages into an XDR buffer for sending |
| 685 | * @xdr: pointer to xdr_stream |
| 686 | * @pages: list of pages |
| 687 | * @base: offset of first byte |
| 688 | * @len: length of data in bytes |
| 689 | * |
| 690 | */ |
| 691 | void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, unsigned int base, |
| 692 | unsigned int len) |
| 693 | { |
| 694 | struct xdr_buf *buf = xdr->buf; |
| 695 | struct kvec *iov = buf->tail; |
| 696 | buf->pages = pages; |
| 697 | buf->page_base = base; |
| 698 | buf->page_len = len; |
| 699 | |
| 700 | iov->iov_base = (char *)xdr->p; |
| 701 | iov->iov_len = 0; |
| 702 | xdr->iov = iov; |
| 703 | |
| 704 | if (len & 3) { |
| 705 | unsigned int pad = 4 - (len & 3); |
| 706 | |
| 707 | BUG_ON(xdr->p >= xdr->end); |
| 708 | iov->iov_base = (char *)xdr->p + (len & 3); |
| 709 | iov->iov_len += pad; |
| 710 | len += pad; |
| 711 | *xdr->p++ = 0; |
| 712 | } |
| 713 | buf->buflen += len; |
| 714 | buf->len += len; |
| 715 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 716 | EXPORT_SYMBOL_GPL(xdr_write_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 718 | static void xdr_set_iov(struct xdr_stream *xdr, struct kvec *iov, |
Trond Myklebust | 1537693 | 2012-06-28 17:17:48 -0400 | [diff] [blame] | 719 | unsigned int len) |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 720 | { |
| 721 | if (len > iov->iov_len) |
| 722 | len = iov->iov_len; |
Trond Myklebust | 1537693 | 2012-06-28 17:17:48 -0400 | [diff] [blame] | 723 | xdr->p = (__be32*)iov->iov_base; |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 724 | xdr->end = (__be32*)(iov->iov_base + len); |
| 725 | xdr->iov = iov; |
| 726 | xdr->page_ptr = NULL; |
| 727 | } |
| 728 | |
| 729 | static int xdr_set_page_base(struct xdr_stream *xdr, |
| 730 | unsigned int base, unsigned int len) |
| 731 | { |
| 732 | unsigned int pgnr; |
| 733 | unsigned int maxlen; |
| 734 | unsigned int pgoff; |
| 735 | unsigned int pgend; |
| 736 | void *kaddr; |
| 737 | |
| 738 | maxlen = xdr->buf->page_len; |
| 739 | if (base >= maxlen) |
| 740 | return -EINVAL; |
| 741 | maxlen -= base; |
| 742 | if (len > maxlen) |
| 743 | len = maxlen; |
| 744 | |
| 745 | base += xdr->buf->page_base; |
| 746 | |
| 747 | pgnr = base >> PAGE_SHIFT; |
| 748 | xdr->page_ptr = &xdr->buf->pages[pgnr]; |
| 749 | kaddr = page_address(*xdr->page_ptr); |
| 750 | |
| 751 | pgoff = base & ~PAGE_MASK; |
| 752 | xdr->p = (__be32*)(kaddr + pgoff); |
| 753 | |
| 754 | pgend = pgoff + len; |
| 755 | if (pgend > PAGE_SIZE) |
| 756 | pgend = PAGE_SIZE; |
| 757 | xdr->end = (__be32*)(kaddr + pgend); |
| 758 | xdr->iov = NULL; |
| 759 | return 0; |
| 760 | } |
| 761 | |
| 762 | static void xdr_set_next_page(struct xdr_stream *xdr) |
| 763 | { |
| 764 | unsigned int newbase; |
| 765 | |
| 766 | newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT; |
| 767 | newbase -= xdr->buf->page_base; |
| 768 | |
| 769 | if (xdr_set_page_base(xdr, newbase, PAGE_SIZE) < 0) |
Trond Myklebust | 1537693 | 2012-06-28 17:17:48 -0400 | [diff] [blame] | 770 | xdr_set_iov(xdr, xdr->buf->tail, xdr->buf->len); |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 771 | } |
| 772 | |
| 773 | static bool xdr_set_next_buffer(struct xdr_stream *xdr) |
| 774 | { |
| 775 | if (xdr->page_ptr != NULL) |
| 776 | xdr_set_next_page(xdr); |
| 777 | else if (xdr->iov == xdr->buf->head) { |
| 778 | if (xdr_set_page_base(xdr, 0, PAGE_SIZE) < 0) |
Trond Myklebust | 1537693 | 2012-06-28 17:17:48 -0400 | [diff] [blame] | 779 | xdr_set_iov(xdr, xdr->buf->tail, xdr->buf->len); |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 780 | } |
| 781 | return xdr->p != xdr->end; |
| 782 | } |
| 783 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | /** |
| 785 | * xdr_init_decode - Initialize an xdr_stream for decoding data. |
| 786 | * @xdr: pointer to xdr_stream struct |
| 787 | * @buf: pointer to XDR buffer from which to decode data |
| 788 | * @p: current pointer inside XDR buffer |
| 789 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 790 | void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 792 | xdr->buf = buf; |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 793 | xdr->scratch.iov_base = NULL; |
| 794 | xdr->scratch.iov_len = 0; |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 795 | xdr->nwords = XDR_QUADLEN(buf->len); |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 796 | if (buf->head[0].iov_len != 0) |
Trond Myklebust | 1537693 | 2012-06-28 17:17:48 -0400 | [diff] [blame] | 797 | xdr_set_iov(xdr, buf->head, buf->len); |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 798 | else if (buf->page_len != 0) |
| 799 | xdr_set_page_base(xdr, 0, buf->len); |
Benjamin Coddington | 06ef26a | 2016-04-06 11:32:52 -0400 | [diff] [blame] | 800 | else |
| 801 | xdr_set_iov(xdr, buf->head, buf->len); |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 802 | if (p != NULL && p > xdr->p && xdr->end >= p) { |
| 803 | xdr->nwords -= p - xdr->p; |
Trond Myklebust | 1537693 | 2012-06-28 17:17:48 -0400 | [diff] [blame] | 804 | xdr->p = p; |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 805 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 806 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 807 | EXPORT_SYMBOL_GPL(xdr_init_decode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | |
Benny Halevy | f7da7a1 | 2011-05-19 14:16:47 -0400 | [diff] [blame] | 809 | /** |
| 810 | * xdr_init_decode - Initialize an xdr_stream for decoding data. |
| 811 | * @xdr: pointer to xdr_stream struct |
| 812 | * @buf: pointer to XDR buffer from which to decode data |
| 813 | * @pages: list of pages to decode into |
| 814 | * @len: length in bytes of buffer in pages |
| 815 | */ |
| 816 | void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, |
| 817 | struct page **pages, unsigned int len) |
| 818 | { |
| 819 | memset(buf, 0, sizeof(*buf)); |
| 820 | buf->pages = pages; |
| 821 | buf->page_len = len; |
| 822 | buf->buflen = len; |
| 823 | buf->len = len; |
| 824 | xdr_init_decode(xdr, buf, NULL); |
| 825 | } |
| 826 | EXPORT_SYMBOL_GPL(xdr_init_decode_pages); |
| 827 | |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 828 | static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) |
Trond Myklebust | ba8e452 | 2010-10-19 19:58:49 -0400 | [diff] [blame] | 829 | { |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 830 | unsigned int nwords = XDR_QUADLEN(nbytes); |
Trond Myklebust | ba8e452 | 2010-10-19 19:58:49 -0400 | [diff] [blame] | 831 | __be32 *p = xdr->p; |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 832 | __be32 *q = p + nwords; |
Trond Myklebust | ba8e452 | 2010-10-19 19:58:49 -0400 | [diff] [blame] | 833 | |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 834 | if (unlikely(nwords > xdr->nwords || q > xdr->end || q < p)) |
Trond Myklebust | ba8e452 | 2010-10-19 19:58:49 -0400 | [diff] [blame] | 835 | return NULL; |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 836 | xdr->p = q; |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 837 | xdr->nwords -= nwords; |
Trond Myklebust | ba8e452 | 2010-10-19 19:58:49 -0400 | [diff] [blame] | 838 | return p; |
| 839 | } |
Trond Myklebust | ba8e452 | 2010-10-19 19:58:49 -0400 | [diff] [blame] | 840 | |
| 841 | /** |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 842 | * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data. |
| 843 | * @xdr: pointer to xdr_stream struct |
| 844 | * @buf: pointer to an empty buffer |
| 845 | * @buflen: size of 'buf' |
| 846 | * |
| 847 | * The scratch buffer is used when decoding from an array of pages. |
| 848 | * If an xdr_inline_decode() call spans across page boundaries, then |
| 849 | * we copy the data into the scratch buffer in order to allow linear |
| 850 | * access. |
| 851 | */ |
| 852 | void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen) |
| 853 | { |
| 854 | xdr->scratch.iov_base = buf; |
| 855 | xdr->scratch.iov_len = buflen; |
| 856 | } |
| 857 | EXPORT_SYMBOL_GPL(xdr_set_scratch_buffer); |
| 858 | |
| 859 | static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes) |
| 860 | { |
| 861 | __be32 *p; |
Trond Myklebust | ace0e14 | 2016-09-20 14:33:42 -0400 | [diff] [blame^] | 862 | char *cpdest = xdr->scratch.iov_base; |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 863 | size_t cplen = (char *)xdr->end - (char *)xdr->p; |
| 864 | |
| 865 | if (nbytes > xdr->scratch.iov_len) |
| 866 | return NULL; |
Trond Myklebust | ace0e14 | 2016-09-20 14:33:42 -0400 | [diff] [blame^] | 867 | p = __xdr_inline_decode(xdr, cplen); |
| 868 | if (p == NULL) |
| 869 | return NULL; |
| 870 | memcpy(cpdest, p, cplen); |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 871 | cpdest += cplen; |
| 872 | nbytes -= cplen; |
| 873 | if (!xdr_set_next_buffer(xdr)) |
| 874 | return NULL; |
| 875 | p = __xdr_inline_decode(xdr, nbytes); |
| 876 | if (p == NULL) |
| 877 | return NULL; |
| 878 | memcpy(cpdest, p, nbytes); |
| 879 | return xdr->scratch.iov_base; |
| 880 | } |
| 881 | |
| 882 | /** |
| 883 | * xdr_inline_decode - Retrieve XDR data to decode |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 884 | * @xdr: pointer to xdr_stream struct |
| 885 | * @nbytes: number of bytes of data to decode |
| 886 | * |
| 887 | * Check if the input buffer is long enough to enable us to decode |
| 888 | * 'nbytes' more bytes of data starting at the current position. |
| 889 | * If so return the current pointer, then update the current |
| 890 | * pointer position. |
| 891 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 892 | __be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 893 | { |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 894 | __be32 *p; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 896 | if (nbytes == 0) |
| 897 | return xdr->p; |
| 898 | if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 899 | return NULL; |
Trond Myklebust | 6650239 | 2011-01-08 17:45:38 -0500 | [diff] [blame] | 900 | p = __xdr_inline_decode(xdr, nbytes); |
| 901 | if (p != NULL) |
| 902 | return p; |
| 903 | return xdr_copy_to_scratch(xdr, nbytes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 904 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 905 | EXPORT_SYMBOL_GPL(xdr_inline_decode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 906 | |
Trond Myklebust | 3994ee6 | 2012-06-26 12:34:05 -0400 | [diff] [blame] | 907 | static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 908 | { |
| 909 | struct xdr_buf *buf = xdr->buf; |
| 910 | struct kvec *iov; |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 911 | unsigned int nwords = XDR_QUADLEN(len); |
Trond Myklebust | b760b31 | 2012-06-26 12:19:55 -0400 | [diff] [blame] | 912 | unsigned int cur = xdr_stream_pos(xdr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 914 | if (xdr->nwords == 0) |
Trond Myklebust | c337d36 | 2012-06-21 17:05:37 -0400 | [diff] [blame] | 915 | return 0; |
Trond Myklebust | a11a2bf | 2012-08-02 13:21:43 -0400 | [diff] [blame] | 916 | /* Realign pages to current pointer position */ |
| 917 | iov = buf->head; |
| 918 | if (iov->iov_len > cur) { |
| 919 | xdr_shrink_bufhead(buf, iov->iov_len - cur); |
| 920 | xdr->nwords = XDR_QUADLEN(buf->len - cur); |
| 921 | } |
| 922 | |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 923 | if (nwords > xdr->nwords) { |
| 924 | nwords = xdr->nwords; |
| 925 | len = nwords << 2; |
| 926 | } |
Trond Myklebust | a11a2bf | 2012-08-02 13:21:43 -0400 | [diff] [blame] | 927 | if (buf->page_len <= len) |
Trond Myklebust | 8a9a8b8 | 2012-08-01 14:32:13 -0400 | [diff] [blame] | 928 | len = buf->page_len; |
Trond Myklebust | a11a2bf | 2012-08-02 13:21:43 -0400 | [diff] [blame] | 929 | else if (nwords < xdr->nwords) { |
| 930 | /* Truncate page data and move it into the tail */ |
| 931 | xdr_shrink_pagelen(buf, buf->page_len - len); |
| 932 | xdr->nwords = XDR_QUADLEN(buf->len - cur); |
| 933 | } |
Trond Myklebust | 3994ee6 | 2012-06-26 12:34:05 -0400 | [diff] [blame] | 934 | return len; |
| 935 | } |
Trond Myklebust | bd00f84 | 2012-06-26 13:50:43 -0400 | [diff] [blame] | 936 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 937 | /** |
| 938 | * xdr_read_pages - Ensure page-based XDR data to decode is aligned at current pointer position |
| 939 | * @xdr: pointer to xdr_stream struct |
| 940 | * @len: number of bytes of page data |
| 941 | * |
| 942 | * Moves data beyond the current pointer position from the XDR head[] buffer |
| 943 | * into the page list. Any data that lies beyond current position + "len" |
| 944 | * bytes is moved into the XDR tail[]. |
Trond Myklebust | 3994ee6 | 2012-06-26 12:34:05 -0400 | [diff] [blame] | 945 | * |
| 946 | * Returns the number of XDR encoded bytes now contained in the pages |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 947 | */ |
Trond Myklebust | 3994ee6 | 2012-06-26 12:34:05 -0400 | [diff] [blame] | 948 | unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 949 | { |
| 950 | struct xdr_buf *buf = xdr->buf; |
| 951 | struct kvec *iov; |
Trond Myklebust | 3994ee6 | 2012-06-26 12:34:05 -0400 | [diff] [blame] | 952 | unsigned int nwords; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 953 | unsigned int end; |
Trond Myklebust | 3994ee6 | 2012-06-26 12:34:05 -0400 | [diff] [blame] | 954 | unsigned int padding; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 955 | |
Trond Myklebust | 3994ee6 | 2012-06-26 12:34:05 -0400 | [diff] [blame] | 956 | len = xdr_align_pages(xdr, len); |
| 957 | if (len == 0) |
| 958 | return 0; |
| 959 | nwords = XDR_QUADLEN(len); |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 960 | padding = (nwords << 2) - len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | xdr->iov = iov = buf->tail; |
| 962 | /* Compute remaining message length. */ |
Trond Myklebust | bd00f84 | 2012-06-26 13:50:43 -0400 | [diff] [blame] | 963 | end = ((xdr->nwords - nwords) << 2) + padding; |
| 964 | if (end > iov->iov_len) |
| 965 | end = iov->iov_len; |
| 966 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 967 | /* |
| 968 | * Position current pointer at beginning of tail, and |
| 969 | * set remaining message length. |
| 970 | */ |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 971 | xdr->p = (__be32 *)((char *)iov->iov_base + padding); |
| 972 | xdr->end = (__be32 *)((char *)iov->iov_base + end); |
Trond Myklebust | 76cacaa | 2012-06-26 15:32:40 -0400 | [diff] [blame] | 973 | xdr->page_ptr = NULL; |
Trond Myklebust | bfeea1d | 2012-06-20 09:58:35 -0400 | [diff] [blame] | 974 | xdr->nwords = XDR_QUADLEN(end - padding); |
Trond Myklebust | c337d36 | 2012-06-21 17:05:37 -0400 | [diff] [blame] | 975 | return len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 977 | EXPORT_SYMBOL_GPL(xdr_read_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 978 | |
Trond Myklebust | 8b23ea7 | 2006-06-09 09:34:21 -0400 | [diff] [blame] | 979 | /** |
| 980 | * xdr_enter_page - decode data from the XDR page |
| 981 | * @xdr: pointer to xdr_stream struct |
| 982 | * @len: number of bytes of page data |
| 983 | * |
| 984 | * Moves data beyond the current pointer position from the XDR head[] buffer |
| 985 | * into the page list. Any data that lies beyond current position + "len" |
| 986 | * bytes is moved into the XDR tail[]. The current pointer is then |
| 987 | * repositioned at the beginning of the first XDR page. |
| 988 | */ |
| 989 | void xdr_enter_page(struct xdr_stream *xdr, unsigned int len) |
| 990 | { |
Trond Myklebust | f8bb7f0 | 2012-06-21 14:53:10 -0400 | [diff] [blame] | 991 | len = xdr_align_pages(xdr, len); |
Trond Myklebust | 8b23ea7 | 2006-06-09 09:34:21 -0400 | [diff] [blame] | 992 | /* |
| 993 | * Position current pointer at beginning of tail, and |
| 994 | * set remaining message length. |
| 995 | */ |
Trond Myklebust | f8bb7f0 | 2012-06-21 14:53:10 -0400 | [diff] [blame] | 996 | if (len != 0) |
| 997 | xdr_set_page_base(xdr, 0, len); |
Trond Myklebust | 8b23ea7 | 2006-06-09 09:34:21 -0400 | [diff] [blame] | 998 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 999 | EXPORT_SYMBOL_GPL(xdr_enter_page); |
Trond Myklebust | 8b23ea7 | 2006-06-09 09:34:21 -0400 | [diff] [blame] | 1000 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1001 | static struct kvec empty_iov = {.iov_base = NULL, .iov_len = 0}; |
| 1002 | |
| 1003 | void |
| 1004 | xdr_buf_from_iov(struct kvec *iov, struct xdr_buf *buf) |
| 1005 | { |
| 1006 | buf->head[0] = *iov; |
| 1007 | buf->tail[0] = empty_iov; |
| 1008 | buf->page_len = 0; |
| 1009 | buf->buflen = buf->len = iov->iov_len; |
| 1010 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1011 | EXPORT_SYMBOL_GPL(xdr_buf_from_iov); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1012 | |
J. Bruce Fields | de4aee2 | 2014-02-25 17:21:08 -0500 | [diff] [blame] | 1013 | /** |
| 1014 | * xdr_buf_subsegment - set subbuf to a portion of buf |
| 1015 | * @buf: an xdr buffer |
| 1016 | * @subbuf: the result buffer |
| 1017 | * @base: beginning of range in bytes |
| 1018 | * @len: length of range in bytes |
| 1019 | * |
| 1020 | * sets @subbuf to an xdr buffer representing the portion of @buf of |
| 1021 | * length @len starting at offset @base. |
| 1022 | * |
| 1023 | * @buf and @subbuf may be pointers to the same struct xdr_buf. |
| 1024 | * |
| 1025 | * Returns -1 if base of length are out of bounds. |
| 1026 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1027 | int |
| 1028 | xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf, |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1029 | unsigned int base, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1030 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1031 | subbuf->buflen = subbuf->len = len; |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1032 | if (base < buf->head[0].iov_len) { |
| 1033 | subbuf->head[0].iov_base = buf->head[0].iov_base + base; |
| 1034 | subbuf->head[0].iov_len = min_t(unsigned int, len, |
| 1035 | buf->head[0].iov_len - base); |
| 1036 | len -= subbuf->head[0].iov_len; |
| 1037 | base = 0; |
| 1038 | } else { |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1039 | base -= buf->head[0].iov_len; |
J. Bruce Fields | de4aee2 | 2014-02-25 17:21:08 -0500 | [diff] [blame] | 1040 | subbuf->head[0].iov_len = 0; |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1041 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1042 | |
| 1043 | if (base < buf->page_len) { |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1044 | subbuf->page_len = min(buf->page_len - base, len); |
| 1045 | base += buf->page_base; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1046 | subbuf->page_base = base & ~PAGE_MASK; |
| 1047 | subbuf->pages = &buf->pages[base >> PAGE_SHIFT]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1048 | len -= subbuf->page_len; |
| 1049 | base = 0; |
| 1050 | } else { |
| 1051 | base -= buf->page_len; |
| 1052 | subbuf->page_len = 0; |
| 1053 | } |
| 1054 | |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1055 | if (base < buf->tail[0].iov_len) { |
| 1056 | subbuf->tail[0].iov_base = buf->tail[0].iov_base + base; |
| 1057 | subbuf->tail[0].iov_len = min_t(unsigned int, len, |
| 1058 | buf->tail[0].iov_len - base); |
| 1059 | len -= subbuf->tail[0].iov_len; |
| 1060 | base = 0; |
| 1061 | } else { |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1062 | base -= buf->tail[0].iov_len; |
J. Bruce Fields | de4aee2 | 2014-02-25 17:21:08 -0500 | [diff] [blame] | 1063 | subbuf->tail[0].iov_len = 0; |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1064 | } |
| 1065 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1066 | if (base || len) |
| 1067 | return -1; |
| 1068 | return 0; |
| 1069 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1070 | EXPORT_SYMBOL_GPL(xdr_buf_subsegment); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1071 | |
Jeff Layton | 4c190e2 | 2013-02-06 08:28:55 -0500 | [diff] [blame] | 1072 | /** |
| 1073 | * xdr_buf_trim - lop at most "len" bytes off the end of "buf" |
| 1074 | * @buf: buf to be trimmed |
| 1075 | * @len: number of bytes to reduce "buf" by |
| 1076 | * |
| 1077 | * Trim an xdr_buf by the given number of bytes by fixing up the lengths. Note |
| 1078 | * that it's possible that we'll trim less than that amount if the xdr_buf is |
| 1079 | * too small, or if (for instance) it's all in the head and the parser has |
| 1080 | * already read too far into it. |
| 1081 | */ |
| 1082 | void xdr_buf_trim(struct xdr_buf *buf, unsigned int len) |
| 1083 | { |
| 1084 | size_t cur; |
| 1085 | unsigned int trim = len; |
| 1086 | |
| 1087 | if (buf->tail[0].iov_len) { |
| 1088 | cur = min_t(size_t, buf->tail[0].iov_len, trim); |
| 1089 | buf->tail[0].iov_len -= cur; |
| 1090 | trim -= cur; |
| 1091 | if (!trim) |
| 1092 | goto fix_len; |
| 1093 | } |
| 1094 | |
| 1095 | if (buf->page_len) { |
| 1096 | cur = min_t(unsigned int, buf->page_len, trim); |
| 1097 | buf->page_len -= cur; |
| 1098 | trim -= cur; |
| 1099 | if (!trim) |
| 1100 | goto fix_len; |
| 1101 | } |
| 1102 | |
| 1103 | if (buf->head[0].iov_len) { |
| 1104 | cur = min_t(size_t, buf->head[0].iov_len, trim); |
| 1105 | buf->head[0].iov_len -= cur; |
| 1106 | trim -= cur; |
| 1107 | } |
| 1108 | fix_len: |
| 1109 | buf->len -= (len - trim); |
| 1110 | } |
| 1111 | EXPORT_SYMBOL_GPL(xdr_buf_trim); |
| 1112 | |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1113 | static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1114 | { |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1115 | unsigned int this_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1116 | |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1117 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); |
| 1118 | memcpy(obj, subbuf->head[0].iov_base, this_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1119 | len -= this_len; |
| 1120 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1121 | this_len = min_t(unsigned int, len, subbuf->page_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1122 | if (this_len) |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1123 | _copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1124 | len -= this_len; |
| 1125 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1126 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
| 1127 | memcpy(obj, subbuf->tail[0].iov_base, this_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | } |
| 1129 | |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1130 | /* obj is assumed to point to allocated memory of size at least len: */ |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1131 | int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len) |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1132 | { |
| 1133 | struct xdr_buf subbuf; |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1134 | int status; |
| 1135 | |
| 1136 | status = xdr_buf_subsegment(buf, &subbuf, base, len); |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1137 | if (status != 0) |
| 1138 | return status; |
| 1139 | __read_bytes_from_xdr_buf(&subbuf, obj, len); |
| 1140 | return 0; |
| 1141 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1142 | EXPORT_SYMBOL_GPL(read_bytes_from_xdr_buf); |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1143 | |
| 1144 | static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len) |
| 1145 | { |
| 1146 | unsigned int this_len; |
| 1147 | |
| 1148 | this_len = min_t(unsigned int, len, subbuf->head[0].iov_len); |
| 1149 | memcpy(subbuf->head[0].iov_base, obj, this_len); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1150 | len -= this_len; |
| 1151 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1152 | this_len = min_t(unsigned int, len, subbuf->page_len); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1153 | if (this_len) |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1154 | _copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1155 | len -= this_len; |
| 1156 | obj += this_len; |
Trond Myklebust | 4e3e43a | 2006-10-17 13:47:24 -0400 | [diff] [blame] | 1157 | this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len); |
| 1158 | memcpy(subbuf->tail[0].iov_base, obj, this_len); |
| 1159 | } |
| 1160 | |
| 1161 | /* obj is assumed to point to allocated memory of size at least len: */ |
| 1162 | int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len) |
| 1163 | { |
| 1164 | struct xdr_buf subbuf; |
| 1165 | int status; |
| 1166 | |
| 1167 | status = xdr_buf_subsegment(buf, &subbuf, base, len); |
| 1168 | if (status != 0) |
| 1169 | return status; |
| 1170 | __write_bytes_to_xdr_buf(&subbuf, obj, len); |
| 1171 | return 0; |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1172 | } |
Kevin Coffman | c43abae | 2010-03-17 13:02:58 -0400 | [diff] [blame] | 1173 | EXPORT_SYMBOL_GPL(write_bytes_to_xdr_buf); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1174 | |
| 1175 | int |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1176 | xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1177 | { |
Alexey Dobriyan | d8ed029 | 2006-09-26 22:29:38 -0700 | [diff] [blame] | 1178 | __be32 raw; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1179 | int status; |
| 1180 | |
| 1181 | status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj)); |
| 1182 | if (status) |
| 1183 | return status; |
Benny Halevy | 98866b5 | 2009-08-14 17:18:49 +0300 | [diff] [blame] | 1184 | *obj = be32_to_cpu(raw); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1185 | return 0; |
| 1186 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1187 | EXPORT_SYMBOL_GPL(xdr_decode_word); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1188 | |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1189 | int |
Trond Myklebust | 1e78957 | 2006-08-31 15:09:19 -0400 | [diff] [blame] | 1190 | xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj) |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1191 | { |
Benny Halevy | 9f162d2 | 2009-08-14 17:18:44 +0300 | [diff] [blame] | 1192 | __be32 raw = cpu_to_be32(obj); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1193 | |
| 1194 | return write_bytes_to_xdr_buf(buf, base, &raw, sizeof(obj)); |
| 1195 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1196 | EXPORT_SYMBOL_GPL(xdr_encode_word); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1197 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1198 | /* If the netobj starting offset bytes from the start of xdr_buf is contained |
| 1199 | * entirely in the head or the tail, set object to point to it; otherwise |
| 1200 | * try to find space for it at the end of the tail, copy it there, and |
| 1201 | * set obj to point to it. */ |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 1202 | int xdr_buf_read_netobj(struct xdr_buf *buf, struct xdr_netobj *obj, unsigned int offset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1203 | { |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 1204 | struct xdr_buf subbuf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1205 | |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1206 | if (xdr_decode_word(buf, offset, &obj->len)) |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 1207 | return -EFAULT; |
| 1208 | if (xdr_buf_subsegment(buf, &subbuf, offset + 4, obj->len)) |
| 1209 | return -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1210 | |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 1211 | /* Is the obj contained entirely in the head? */ |
| 1212 | obj->data = subbuf.head[0].iov_base; |
| 1213 | if (subbuf.head[0].iov_len == obj->len) |
| 1214 | return 0; |
| 1215 | /* ..or is the obj contained entirely in the tail? */ |
| 1216 | obj->data = subbuf.tail[0].iov_base; |
| 1217 | if (subbuf.tail[0].iov_len == obj->len) |
| 1218 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1219 | |
Trond Myklebust | bee57c9 | 2006-10-09 22:08:22 -0400 | [diff] [blame] | 1220 | /* use end of tail as storage for obj: |
| 1221 | * (We don't copy to the beginning because then we'd have |
| 1222 | * to worry about doing a potentially overlapping copy. |
| 1223 | * This assumes the object is at most half the length of the |
| 1224 | * tail.) */ |
| 1225 | if (obj->len > buf->buflen - buf->len) |
| 1226 | return -ENOMEM; |
| 1227 | if (buf->tail[0].iov_len != 0) |
| 1228 | obj->data = buf->tail[0].iov_base + buf->tail[0].iov_len; |
| 1229 | else |
| 1230 | obj->data = buf->head[0].iov_base + buf->head[0].iov_len; |
| 1231 | __read_bytes_from_xdr_buf(&subbuf, obj->data, obj->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1232 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1233 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1234 | EXPORT_SYMBOL_GPL(xdr_buf_read_netobj); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1235 | |
| 1236 | /* Returns 0 on success, or else a negative error code. */ |
| 1237 | static int |
| 1238 | xdr_xcode_array2(struct xdr_buf *buf, unsigned int base, |
| 1239 | struct xdr_array2_desc *desc, int encode) |
| 1240 | { |
| 1241 | char *elem = NULL, *c; |
| 1242 | unsigned int copied = 0, todo, avail_here; |
| 1243 | struct page **ppages = NULL; |
| 1244 | int err; |
| 1245 | |
| 1246 | if (encode) { |
| 1247 | if (xdr_encode_word(buf, base, desc->array_len) != 0) |
| 1248 | return -EINVAL; |
| 1249 | } else { |
| 1250 | if (xdr_decode_word(buf, base, &desc->array_len) != 0 || |
Trond Myklebust | 58fcb8d | 2005-08-10 18:15:12 -0400 | [diff] [blame] | 1251 | desc->array_len > desc->array_maxlen || |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1252 | (unsigned long) base + 4 + desc->array_len * |
| 1253 | desc->elem_size > buf->len) |
| 1254 | return -EINVAL; |
| 1255 | } |
| 1256 | base += 4; |
| 1257 | |
| 1258 | if (!desc->xcode) |
| 1259 | return 0; |
| 1260 | |
| 1261 | todo = desc->array_len * desc->elem_size; |
| 1262 | |
| 1263 | /* process head */ |
| 1264 | if (todo && base < buf->head->iov_len) { |
| 1265 | c = buf->head->iov_base + base; |
| 1266 | avail_here = min_t(unsigned int, todo, |
| 1267 | buf->head->iov_len - base); |
| 1268 | todo -= avail_here; |
| 1269 | |
| 1270 | while (avail_here >= desc->elem_size) { |
| 1271 | err = desc->xcode(desc, c); |
| 1272 | if (err) |
| 1273 | goto out; |
| 1274 | c += desc->elem_size; |
| 1275 | avail_here -= desc->elem_size; |
| 1276 | } |
| 1277 | if (avail_here) { |
| 1278 | if (!elem) { |
| 1279 | elem = kmalloc(desc->elem_size, GFP_KERNEL); |
| 1280 | err = -ENOMEM; |
| 1281 | if (!elem) |
| 1282 | goto out; |
| 1283 | } |
| 1284 | if (encode) { |
| 1285 | err = desc->xcode(desc, elem); |
| 1286 | if (err) |
| 1287 | goto out; |
| 1288 | memcpy(c, elem, avail_here); |
| 1289 | } else |
| 1290 | memcpy(elem, c, avail_here); |
| 1291 | copied = avail_here; |
| 1292 | } |
| 1293 | base = buf->head->iov_len; /* align to start of pages */ |
| 1294 | } |
| 1295 | |
| 1296 | /* process pages array */ |
| 1297 | base -= buf->head->iov_len; |
| 1298 | if (todo && base < buf->page_len) { |
| 1299 | unsigned int avail_page; |
| 1300 | |
| 1301 | avail_here = min(todo, buf->page_len - base); |
| 1302 | todo -= avail_here; |
| 1303 | |
| 1304 | base += buf->page_base; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1305 | ppages = buf->pages + (base >> PAGE_SHIFT); |
| 1306 | base &= ~PAGE_MASK; |
| 1307 | avail_page = min_t(unsigned int, PAGE_SIZE - base, |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1308 | avail_here); |
| 1309 | c = kmap(*ppages) + base; |
| 1310 | |
| 1311 | while (avail_here) { |
| 1312 | avail_here -= avail_page; |
| 1313 | if (copied || avail_page < desc->elem_size) { |
| 1314 | unsigned int l = min(avail_page, |
| 1315 | desc->elem_size - copied); |
| 1316 | if (!elem) { |
| 1317 | elem = kmalloc(desc->elem_size, |
| 1318 | GFP_KERNEL); |
| 1319 | err = -ENOMEM; |
| 1320 | if (!elem) |
| 1321 | goto out; |
| 1322 | } |
| 1323 | if (encode) { |
| 1324 | if (!copied) { |
| 1325 | err = desc->xcode(desc, elem); |
| 1326 | if (err) |
| 1327 | goto out; |
| 1328 | } |
| 1329 | memcpy(c, elem + copied, l); |
| 1330 | copied += l; |
| 1331 | if (copied == desc->elem_size) |
| 1332 | copied = 0; |
| 1333 | } else { |
| 1334 | memcpy(elem + copied, c, l); |
| 1335 | copied += l; |
| 1336 | if (copied == desc->elem_size) { |
| 1337 | err = desc->xcode(desc, elem); |
| 1338 | if (err) |
| 1339 | goto out; |
| 1340 | copied = 0; |
| 1341 | } |
| 1342 | } |
| 1343 | avail_page -= l; |
| 1344 | c += l; |
| 1345 | } |
| 1346 | while (avail_page >= desc->elem_size) { |
| 1347 | err = desc->xcode(desc, c); |
| 1348 | if (err) |
| 1349 | goto out; |
| 1350 | c += desc->elem_size; |
| 1351 | avail_page -= desc->elem_size; |
| 1352 | } |
| 1353 | if (avail_page) { |
| 1354 | unsigned int l = min(avail_page, |
| 1355 | desc->elem_size - copied); |
| 1356 | if (!elem) { |
| 1357 | elem = kmalloc(desc->elem_size, |
| 1358 | GFP_KERNEL); |
| 1359 | err = -ENOMEM; |
| 1360 | if (!elem) |
| 1361 | goto out; |
| 1362 | } |
| 1363 | if (encode) { |
| 1364 | if (!copied) { |
| 1365 | err = desc->xcode(desc, elem); |
| 1366 | if (err) |
| 1367 | goto out; |
| 1368 | } |
| 1369 | memcpy(c, elem + copied, l); |
| 1370 | copied += l; |
| 1371 | if (copied == desc->elem_size) |
| 1372 | copied = 0; |
| 1373 | } else { |
| 1374 | memcpy(elem + copied, c, l); |
| 1375 | copied += l; |
| 1376 | if (copied == desc->elem_size) { |
| 1377 | err = desc->xcode(desc, elem); |
| 1378 | if (err) |
| 1379 | goto out; |
| 1380 | copied = 0; |
| 1381 | } |
| 1382 | } |
| 1383 | } |
| 1384 | if (avail_here) { |
| 1385 | kunmap(*ppages); |
| 1386 | ppages++; |
| 1387 | c = kmap(*ppages); |
| 1388 | } |
| 1389 | |
| 1390 | avail_page = min(avail_here, |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1391 | (unsigned int) PAGE_SIZE); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1392 | } |
| 1393 | base = buf->page_len; /* align to start of tail */ |
| 1394 | } |
| 1395 | |
| 1396 | /* process tail */ |
| 1397 | base -= buf->page_len; |
| 1398 | if (todo) { |
| 1399 | c = buf->tail->iov_base + base; |
| 1400 | if (copied) { |
| 1401 | unsigned int l = desc->elem_size - copied; |
| 1402 | |
| 1403 | if (encode) |
| 1404 | memcpy(c, elem + copied, l); |
| 1405 | else { |
| 1406 | memcpy(elem + copied, c, l); |
| 1407 | err = desc->xcode(desc, elem); |
| 1408 | if (err) |
| 1409 | goto out; |
| 1410 | } |
| 1411 | todo -= l; |
| 1412 | c += l; |
| 1413 | } |
| 1414 | while (todo) { |
| 1415 | err = desc->xcode(desc, c); |
| 1416 | if (err) |
| 1417 | goto out; |
| 1418 | c += desc->elem_size; |
| 1419 | todo -= desc->elem_size; |
| 1420 | } |
| 1421 | } |
| 1422 | err = 0; |
| 1423 | |
| 1424 | out: |
Jesper Juhl | a51482b | 2005-11-08 09:41:34 -0800 | [diff] [blame] | 1425 | kfree(elem); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1426 | if (ppages) |
| 1427 | kunmap(*ppages); |
| 1428 | return err; |
| 1429 | } |
| 1430 | |
| 1431 | int |
| 1432 | xdr_decode_array2(struct xdr_buf *buf, unsigned int base, |
| 1433 | struct xdr_array2_desc *desc) |
| 1434 | { |
| 1435 | if (base >= buf->len) |
| 1436 | return -EINVAL; |
| 1437 | |
| 1438 | return xdr_xcode_array2(buf, base, desc, 0); |
| 1439 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1440 | EXPORT_SYMBOL_GPL(xdr_decode_array2); |
Andreas Gruenbacher | bd8100e | 2005-06-22 17:16:24 +0000 | [diff] [blame] | 1441 | |
| 1442 | int |
| 1443 | xdr_encode_array2(struct xdr_buf *buf, unsigned int base, |
| 1444 | struct xdr_array2_desc *desc) |
| 1445 | { |
| 1446 | if ((unsigned long) base + 4 + desc->array_len * desc->elem_size > |
| 1447 | buf->head->iov_len + buf->page_len + buf->tail->iov_len) |
| 1448 | return -EINVAL; |
| 1449 | |
| 1450 | return xdr_xcode_array2(buf, base, desc, 1); |
| 1451 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1452 | EXPORT_SYMBOL_GPL(xdr_encode_array2); |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1453 | |
| 1454 | int |
| 1455 | xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, |
YOSHIFUJI Hideaki | cca5172 | 2007-02-09 15:38:13 -0800 | [diff] [blame] | 1456 | int (*actor)(struct scatterlist *, void *), void *data) |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1457 | { |
| 1458 | int i, ret = 0; |
Eric Dumazet | 95c9617 | 2012-04-15 05:58:06 +0000 | [diff] [blame] | 1459 | unsigned int page_len, thislen, page_offset; |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1460 | struct scatterlist sg[1]; |
| 1461 | |
Herbert Xu | 68e3f5d | 2007-10-27 00:52:07 -0700 | [diff] [blame] | 1462 | sg_init_table(sg, 1); |
| 1463 | |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1464 | if (offset >= buf->head[0].iov_len) { |
| 1465 | offset -= buf->head[0].iov_len; |
| 1466 | } else { |
| 1467 | thislen = buf->head[0].iov_len - offset; |
| 1468 | if (thislen > len) |
| 1469 | thislen = len; |
| 1470 | sg_set_buf(sg, buf->head[0].iov_base + offset, thislen); |
| 1471 | ret = actor(sg, data); |
| 1472 | if (ret) |
| 1473 | goto out; |
| 1474 | offset = 0; |
| 1475 | len -= thislen; |
| 1476 | } |
| 1477 | if (len == 0) |
| 1478 | goto out; |
| 1479 | |
| 1480 | if (offset >= buf->page_len) { |
| 1481 | offset -= buf->page_len; |
| 1482 | } else { |
| 1483 | page_len = buf->page_len - offset; |
| 1484 | if (page_len > len) |
| 1485 | page_len = len; |
| 1486 | len -= page_len; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1487 | page_offset = (offset + buf->page_base) & (PAGE_SIZE - 1); |
| 1488 | i = (offset + buf->page_base) >> PAGE_SHIFT; |
| 1489 | thislen = PAGE_SIZE - page_offset; |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1490 | do { |
| 1491 | if (thislen > page_len) |
| 1492 | thislen = page_len; |
Jens Axboe | 642f149 | 2007-10-24 11:20:47 +0200 | [diff] [blame] | 1493 | sg_set_page(sg, buf->pages[i], thislen, page_offset); |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1494 | ret = actor(sg, data); |
| 1495 | if (ret) |
| 1496 | goto out; |
| 1497 | page_len -= thislen; |
| 1498 | i++; |
| 1499 | page_offset = 0; |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1500 | thislen = PAGE_SIZE; |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1501 | } while (page_len != 0); |
| 1502 | offset = 0; |
| 1503 | } |
| 1504 | if (len == 0) |
| 1505 | goto out; |
| 1506 | if (offset < buf->tail[0].iov_len) { |
| 1507 | thislen = buf->tail[0].iov_len - offset; |
| 1508 | if (thislen > len) |
| 1509 | thislen = len; |
| 1510 | sg_set_buf(sg, buf->tail[0].iov_base + offset, thislen); |
| 1511 | ret = actor(sg, data); |
| 1512 | len -= thislen; |
| 1513 | } |
| 1514 | if (len != 0) |
| 1515 | ret = -EINVAL; |
| 1516 | out: |
| 1517 | return ret; |
| 1518 | } |
Trond Myklebust | 468039e | 2008-12-23 15:21:31 -0500 | [diff] [blame] | 1519 | EXPORT_SYMBOL_GPL(xdr_process_buf); |
Olga Kornievskaia | 37a4e6c | 2006-12-04 20:22:33 -0500 | [diff] [blame] | 1520 | |