linux-2.6.33/generic_segment_checks() の変更点

• 追加された行はこの色です。
• 削除された行はこの色です。
• linux-2.6.33/generic_segment_checks() へ行く。
• linux-2.6.33/generic_segment_checks() の差分を削除

*参照元 [#c270f447]
#backlinks

*説明 [#ofeb965b]
-パス: [[linux-2.6.33/mm/filemap.c]]

-FIXME: これは何？
--説明


**引数 [#g51d9c69]
-const struct iovec *iov
--
--[[linux-2.6.33/iovec]]
-unsigned long *nr_segs
--
-size_t *count
--
-int access_flags
--

**返り値 [#e27d5b13]
-
--

**参考 [#wb3f9297]


*実装 [#u1347f59]
 /*
  * Performs necessary checks before doing a write
  * @iov:	io vector request
  * @nr_segs:	number of segments in the iovec
  * @count:	number of bytes to write
  * @access_flags: type of access: %VERIFY_READ or %VERIFY_WRITE
  *
  * Adjust number of segments and amount of bytes to write (nr_segs should be
  * properly initialized first). Returns appropriate error code that caller
  * should return or zero in case that write should be allowed.
  */
 int generic_segment_checks(const struct iovec *iov,
 			unsigned long *nr_segs, size_t *count, int access_flags)
 {
 	unsigned long   seg;
 	size_t cnt = 0;
 	for (seg = 0; seg < *nr_segs; seg++) {
 		const struct iovec *iv = &iov[seg];
 
 		/*
 		 * If any segment has a negative length, or the cumulative
 		 * length ever wraps negative then return -EINVAL.
 		 */
 		cnt += iv->iov_len;
 		if (unlikely((ssize_t)(cnt|iv->iov_len) < 0))
 			return -EINVAL;
-
--[[linux-2.6.33/unlikely()]]

 		if (access_ok(access_flags, iv->iov_base, iv->iov_len))
 			continue;
-
--[[linux-2.6.33/access_ok()]]

 		if (seg == 0)
 			return -EFAULT;
 		*nr_segs = seg;
 		cnt -= iv->iov_len;	/* This segment is no good */
 		break;
 	}
 	*count = cnt;
 	return 0;
 }
 EXPORT_SYMBOL(generic_segment_checks);
-特にライセンスを区別せずシンボルを公開する。
--[[linux-2.6.33/EXPORT_SYMBOL()]]


*コメント [#e619c6a6]