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1 | e4d5639d | Amit Shah | /*
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2 | e4d5639d | Amit Shah | * Helpers for getting linearized buffers from iov / filling buffers into iovs
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3 | e4d5639d | Amit Shah | *
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4 | e4d5639d | Amit Shah | * Copyright IBM, Corp. 2007, 2008
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5 | e4d5639d | Amit Shah | * Copyright (C) 2010 Red Hat, Inc.
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6 | e4d5639d | Amit Shah | *
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7 | e4d5639d | Amit Shah | * Author(s):
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8 | e4d5639d | Amit Shah | * Anthony Liguori <aliguori@us.ibm.com>
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9 | e4d5639d | Amit Shah | * Amit Shah <amit.shah@redhat.com>
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10 | e4d5639d | Amit Shah | *
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11 | e4d5639d | Amit Shah | * This work is licensed under the terms of the GNU GPL, version 2. See
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12 | e4d5639d | Amit Shah | * the COPYING file in the top-level directory.
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13 | e4d5639d | Amit Shah | */
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14 | e4d5639d | Amit Shah | |
15 | e4d5639d | Amit Shah | #include "iov.h" |
16 | e4d5639d | Amit Shah | |
17 | e4d5639d | Amit Shah | size_t iov_from_buf(struct iovec *iov, unsigned int iovcnt, |
18 | e4d5639d | Amit Shah | const void *buf, size_t size) |
19 | e4d5639d | Amit Shah | { |
20 | e4d5639d | Amit Shah | size_t offset; |
21 | e4d5639d | Amit Shah | unsigned int i; |
22 | e4d5639d | Amit Shah | |
23 | e4d5639d | Amit Shah | offset = 0;
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24 | e4d5639d | Amit Shah | for (i = 0; offset < size && i < iovcnt; i++) { |
25 | e4d5639d | Amit Shah | size_t len; |
26 | e4d5639d | Amit Shah | |
27 | e4d5639d | Amit Shah | len = MIN(iov[i].iov_len, size - offset); |
28 | e4d5639d | Amit Shah | |
29 | e4d5639d | Amit Shah | memcpy(iov[i].iov_base, buf + offset, len); |
30 | e4d5639d | Amit Shah | offset += len; |
31 | e4d5639d | Amit Shah | } |
32 | e4d5639d | Amit Shah | return offset;
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33 | e4d5639d | Amit Shah | } |
34 | fa6111f2 | Amit Shah | |
35 | fa6111f2 | Amit Shah | size_t iov_to_buf(const struct iovec *iov, const unsigned int iovcnt, |
36 | fa6111f2 | Amit Shah | void *buf, size_t offset, size_t size)
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37 | fa6111f2 | Amit Shah | { |
38 | fa6111f2 | Amit Shah | uint8_t *ptr; |
39 | fa6111f2 | Amit Shah | size_t iov_off, buf_off; |
40 | fa6111f2 | Amit Shah | unsigned int i; |
41 | fa6111f2 | Amit Shah | |
42 | fa6111f2 | Amit Shah | ptr = buf; |
43 | fa6111f2 | Amit Shah | iov_off = 0;
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44 | fa6111f2 | Amit Shah | buf_off = 0;
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45 | fa6111f2 | Amit Shah | for (i = 0; i < iovcnt && size; i++) { |
46 | fa6111f2 | Amit Shah | if (offset < (iov_off + iov[i].iov_len)) {
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47 | fa6111f2 | Amit Shah | size_t len = MIN((iov_off + iov[i].iov_len) - offset , size); |
48 | fa6111f2 | Amit Shah | |
49 | fa6111f2 | Amit Shah | memcpy(ptr + buf_off, iov[i].iov_base + (offset - iov_off), len); |
50 | fa6111f2 | Amit Shah | |
51 | fa6111f2 | Amit Shah | buf_off += len; |
52 | fa6111f2 | Amit Shah | offset += len; |
53 | fa6111f2 | Amit Shah | size -= len; |
54 | fa6111f2 | Amit Shah | } |
55 | fa6111f2 | Amit Shah | iov_off += iov[i].iov_len; |
56 | fa6111f2 | Amit Shah | } |
57 | fa6111f2 | Amit Shah | return buf_off;
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58 | fa6111f2 | Amit Shah | } |
59 | fa6111f2 | Amit Shah | |
60 | fa6111f2 | Amit Shah | size_t iov_size(const struct iovec *iov, const unsigned int iovcnt) |
61 | fa6111f2 | Amit Shah | { |
62 | fa6111f2 | Amit Shah | size_t len; |
63 | fa6111f2 | Amit Shah | unsigned int i; |
64 | fa6111f2 | Amit Shah | |
65 | fa6111f2 | Amit Shah | len = 0;
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66 | fa6111f2 | Amit Shah | for (i = 0; i < iovcnt; i++) { |
67 | fa6111f2 | Amit Shah | len += iov[i].iov_len; |
68 | fa6111f2 | Amit Shah | } |
69 | fa6111f2 | Amit Shah | return len;
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70 | fa6111f2 | Amit Shah | } |