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-rw-r--r--lib/iov_iter.c24
1 files changed, 2 insertions, 22 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 9e8c7386b3a0..7e3138cfc8c9 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -291,33 +291,13 @@ done:
291} 291}
292 292
293/* 293/*
294 * Fault in the first iovec of the given iov_iter, to a maximum length
295 * of bytes. Returns 0 on success, or non-zero if the memory could not be
296 * accessed (ie. because it is an invalid address).
297 *
298 * writev-intensive code may want this to prefault several iovecs -- that
299 * would be possible (callers must not rely on the fact that _only_ the
300 * first iovec will be faulted with the current implementation).
301 */
302int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes)
303{
304 if (!(i->type & (ITER_BVEC|ITER_KVEC))) {
305 char __user *buf = i->iov->iov_base + i->iov_offset;
306 bytes = min(bytes, i->iov->iov_len - i->iov_offset);
307 return fault_in_pages_readable(buf, bytes);
308 }
309 return 0;
310}
311EXPORT_SYMBOL(iov_iter_fault_in_readable);
312
313/*
314 * Fault in one or more iovecs of the given iov_iter, to a maximum length of 294 * Fault in one or more iovecs of the given iov_iter, to a maximum length of
315 * bytes. For each iovec, fault in each page that constitutes the iovec. 295 * bytes. For each iovec, fault in each page that constitutes the iovec.
316 * 296 *
317 * Return 0 on success, or non-zero if the memory could not be accessed (i.e. 297 * Return 0 on success, or non-zero if the memory could not be accessed (i.e.
318 * because it is an invalid address). 298 * because it is an invalid address).
319 */ 299 */
320int iov_iter_fault_in_multipages_readable(struct iov_iter *i, size_t bytes) 300int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes)
321{ 301{
322 size_t skip = i->iov_offset; 302 size_t skip = i->iov_offset;
323 const struct iovec *iov; 303 const struct iovec *iov;
@@ -334,7 +314,7 @@ int iov_iter_fault_in_multipages_readable(struct iov_iter *i, size_t bytes)
334 } 314 }
335 return 0; 315 return 0;
336} 316}
337EXPORT_SYMBOL(iov_iter_fault_in_multipages_readable); 317EXPORT_SYMBOL(iov_iter_fault_in_readable);
338 318
339void iov_iter_init(struct iov_iter *i, int direction, 319void iov_iter_init(struct iov_iter *i, int direction,
340 const struct iovec *iov, unsigned long nr_segs, 320 const struct iovec *iov, unsigned long nr_segs,