Scsi - Index of

238 (sg->offset + *offset) & (PAGE_SIZE-1);
239 unsigned int sglen = sg->length - *offset;
240
241 if (sglen > buflen - cnt) {
242
243 /* Transfer ends within this s-g entry */
244 sglen = buflen - cnt;
245 *offset += sglen;
246 } else {
247
248 /* Transfer continues to next s-g entry */
249 *offset = 0;
250 ++*index;
251 ++sg;
252 }
253
254 /* Transfer the data for all the pages in this
255 * s-g entry. For each page: call kmap(), do the
256 * transfer, and call kunmap() immediately after. */
257 while (sglen > 0) {
258 unsigned int plen = min(sglen, (unsigned int)
259 PAGE_SIZE - poff);
260 unsigned char *ptr = kmap(page);
261
262 if (dir == TO_XFER_BUF)
263 memcpy(ptr + poff, buffer + cnt, plen);
264 else
265 memcpy(buffer + cnt, ptr + poff, plen);
266 kunmap(page);
267
268 /* Start at the beginning of the next page */
269 poff = 0;
270 ++page;
271 cnt += plen;
272 sglen -= plen;
273 }
274 }
134
275 }
276
277 /* Return the amount actually transferred */
278 return cnt;
279 }
风,总是在最温柔的时候醉人;