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-rw-r--r--qemu/util/iov.c580
1 files changed, 0 insertions, 580 deletions
diff --git a/qemu/util/iov.c b/qemu/util/iov.c
deleted file mode 100644
index 003fcce66..000000000
--- a/qemu/util/iov.c
+++ /dev/null
@@ -1,580 +0,0 @@
-/*
- * Helpers for getting linearized buffers from iov / filling buffers into iovs
- *
- * Copyright IBM, Corp. 2007, 2008
- * Copyright (C) 2010 Red Hat, Inc.
- *
- * Author(s):
- * Anthony Liguori <aliguori@us.ibm.com>
- * Amit Shah <amit.shah@redhat.com>
- * Michael Tokarev <mjt@tls.msk.ru>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include "qemu/osdep.h"
-#include "qemu-common.h"
-#include "qemu/iov.h"
-#include "qemu/sockets.h"
-#include "qemu/cutils.h"
-
-size_t iov_from_buf_full(const struct iovec *iov, unsigned int iov_cnt,
- size_t offset, const void *buf, size_t bytes)
-{
- size_t done;
- unsigned int i;
- for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) {
- if (offset < iov[i].iov_len) {
- size_t len = MIN(iov[i].iov_len - offset, bytes - done);
- memcpy(iov[i].iov_base + offset, buf + done, len);
- done += len;
- offset = 0;
- } else {
- offset -= iov[i].iov_len;
- }
- }
- assert(offset == 0);
- return done;
-}
-
-size_t iov_to_buf_full(const struct iovec *iov, const unsigned int iov_cnt,
- size_t offset, void *buf, size_t bytes)
-{
- size_t done;
- unsigned int i;
- for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) {
- if (offset < iov[i].iov_len) {
- size_t len = MIN(iov[i].iov_len - offset, bytes - done);
- memcpy(buf + done, iov[i].iov_base + offset, len);
- done += len;
- offset = 0;
- } else {
- offset -= iov[i].iov_len;
- }
- }
- assert(offset == 0);
- return done;
-}
-
-size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt,
- size_t offset, int fillc, size_t bytes)
-{
- size_t done;
- unsigned int i;
- for (i = 0, done = 0; (offset || done < bytes) && i < iov_cnt; i++) {
- if (offset < iov[i].iov_len) {
- size_t len = MIN(iov[i].iov_len - offset, bytes - done);
- memset(iov[i].iov_base + offset, fillc, len);
- done += len;
- offset = 0;
- } else {
- offset -= iov[i].iov_len;
- }
- }
- assert(offset == 0);
- return done;
-}
-
-size_t iov_size(const struct iovec *iov, const unsigned int iov_cnt)
-{
- size_t len;
- unsigned int i;
-
- len = 0;
- for (i = 0; i < iov_cnt; i++) {
- len += iov[i].iov_len;
- }
- return len;
-}
-
-/* helper function for iov_send_recv() */
-static ssize_t
-do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
-{
-#ifdef CONFIG_POSIX
- ssize_t ret;
- struct msghdr msg;
- memset(&msg, 0, sizeof(msg));
- msg.msg_iov = iov;
- msg.msg_iovlen = iov_cnt;
- do {
- ret = do_send
- ? sendmsg(sockfd, &msg, 0)
- : recvmsg(sockfd, &msg, 0);
- } while (ret < 0 && errno == EINTR);
- return ret;
-#else
- /* else send piece-by-piece */
- /*XXX Note: windows has WSASend() and WSARecv() */
- unsigned i = 0;
- ssize_t ret = 0;
- while (i < iov_cnt) {
- ssize_t r = do_send
- ? send(sockfd, iov[i].iov_base, iov[i].iov_len, 0)
- : recv(sockfd, iov[i].iov_base, iov[i].iov_len, 0);
- if (r > 0) {
- ret += r;
- } else if (!r) {
- break;
- } else if (errno == EINTR) {
- continue;
- } else {
- /* else it is some "other" error,
- * only return if there was no data processed. */
- if (ret == 0) {
- ret = -1;
- }
- break;
- }
- i++;
- }
- return ret;
-#endif
-}
-
-ssize_t iov_send_recv(int sockfd, const struct iovec *_iov, unsigned iov_cnt,
- size_t offset, size_t bytes,
- bool do_send)
-{
- ssize_t total = 0;
- ssize_t ret;
- size_t orig_len, tail;
- unsigned niov;
- struct iovec *local_iov, *iov;
-
- if (bytes <= 0) {
- return 0;
- }
-
- local_iov = g_new0(struct iovec, iov_cnt);
- iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes);
- offset = 0;
- iov = local_iov;
-
- while (bytes > 0) {
- /* Find the start position, skipping `offset' bytes:
- * first, skip all full-sized vector elements, */
- for (niov = 0; niov < iov_cnt && offset >= iov[niov].iov_len; ++niov) {
- offset -= iov[niov].iov_len;
- }
-
- /* niov == iov_cnt would only be valid if bytes == 0, which
- * we already ruled out in the loop condition. */
- assert(niov < iov_cnt);
- iov += niov;
- iov_cnt -= niov;
-
- if (offset) {
- /* second, skip `offset' bytes from the (now) first element,
- * undo it on exit */
- iov[0].iov_base += offset;
- iov[0].iov_len -= offset;
- }
- /* Find the end position skipping `bytes' bytes: */
- /* first, skip all full-sized elements */
- tail = bytes;
- for (niov = 0; niov < iov_cnt && iov[niov].iov_len <= tail; ++niov) {
- tail -= iov[niov].iov_len;
- }
- if (tail) {
- /* second, fixup the last element, and remember the original
- * length */
- assert(niov < iov_cnt);
- assert(iov[niov].iov_len > tail);
- orig_len = iov[niov].iov_len;
- iov[niov++].iov_len = tail;
- ret = do_send_recv(sockfd, iov, niov, do_send);
- /* Undo the changes above before checking for errors */
- iov[niov-1].iov_len = orig_len;
- } else {
- ret = do_send_recv(sockfd, iov, niov, do_send);
- }
- if (offset) {
- iov[0].iov_base -= offset;
- iov[0].iov_len += offset;
- }
-
- if (ret < 0) {
- assert(errno != EINTR);
- g_free(local_iov);
- if (errno == EAGAIN && total > 0) {
- return total;
- }
- return -1;
- }
-
- if (ret == 0 && !do_send) {
- /* recv returns 0 when the peer has performed an orderly
- * shutdown. */
- break;
- }
-
- /* Prepare for the next iteration */
- offset += ret;
- total += ret;
- bytes -= ret;
- }
-
- g_free(local_iov);
- return total;
-}
-
-
-void iov_hexdump(const struct iovec *iov, const unsigned int iov_cnt,
- FILE *fp, const char *prefix, size_t limit)
-{
- int v;
- size_t size = 0;
- char *buf;
-
- for (v = 0; v < iov_cnt; v++) {
- size += iov[v].iov_len;
- }
- size = size > limit ? limit : size;
- buf = g_malloc(size);
- iov_to_buf(iov, iov_cnt, 0, buf, size);
- qemu_hexdump(buf, fp, prefix, size);
- g_free(buf);
-}
-
-unsigned iov_copy(struct iovec *dst_iov, unsigned int dst_iov_cnt,
- const struct iovec *iov, unsigned int iov_cnt,
- size_t offset, size_t bytes)
-{
- size_t len;
- unsigned int i, j;
- for (i = 0, j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) {
- if (offset >= iov[i].iov_len) {
- offset -= iov[i].iov_len;
- continue;
- }
- len = MIN(bytes, iov[i].iov_len - offset);
-
- dst_iov[j].iov_base = iov[i].iov_base + offset;
- dst_iov[j].iov_len = len;
- j++;
- bytes -= len;
- offset = 0;
- }
- assert(offset == 0);
- return j;
-}
-
-/* io vectors */
-
-void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint)
-{
- qiov->iov = g_new(struct iovec, alloc_hint);
- qiov->niov = 0;
- qiov->nalloc = alloc_hint;
- qiov->size = 0;
-}
-
-void qemu_iovec_init_external(QEMUIOVector *qiov, struct iovec *iov, int niov)
-{
- int i;
-
- qiov->iov = iov;
- qiov->niov = niov;
- qiov->nalloc = -1;
- qiov->size = 0;
- for (i = 0; i < niov; i++)
- qiov->size += iov[i].iov_len;
-}
-
-void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len)
-{
- assert(qiov->nalloc != -1);
-
- if (qiov->niov == qiov->nalloc) {
- qiov->nalloc = 2 * qiov->nalloc + 1;
- qiov->iov = g_renew(struct iovec, qiov->iov, qiov->nalloc);
- }
- qiov->iov[qiov->niov].iov_base = base;
- qiov->iov[qiov->niov].iov_len = len;
- qiov->size += len;
- ++qiov->niov;
-}
-
-/*
- * Concatenates (partial) iovecs from src_iov to the end of dst.
- * It starts copying after skipping `soffset' bytes at the
- * beginning of src and adds individual vectors from src to
- * dst copies up to `sbytes' bytes total, or up to the end
- * of src_iov if it comes first. This way, it is okay to specify
- * very large value for `sbytes' to indicate "up to the end
- * of src".
- * Only vector pointers are processed, not the actual data buffers.
- */
-size_t qemu_iovec_concat_iov(QEMUIOVector *dst,
- struct iovec *src_iov, unsigned int src_cnt,
- size_t soffset, size_t sbytes)
-{
- int i;
- size_t done;
-
- if (!sbytes) {
- return 0;
- }
- assert(dst->nalloc != -1);
- for (i = 0, done = 0; done < sbytes && i < src_cnt; i++) {
- if (soffset < src_iov[i].iov_len) {
- size_t len = MIN(src_iov[i].iov_len - soffset, sbytes - done);
- qemu_iovec_add(dst, src_iov[i].iov_base + soffset, len);
- done += len;
- soffset = 0;
- } else {
- soffset -= src_iov[i].iov_len;
- }
- }
- assert(soffset == 0); /* offset beyond end of src */
-
- return done;
-}
-
-/*
- * Concatenates (partial) iovecs from src to the end of dst.
- * It starts copying after skipping `soffset' bytes at the
- * beginning of src and adds individual vectors from src to
- * dst copies up to `sbytes' bytes total, or up to the end
- * of src if it comes first. This way, it is okay to specify
- * very large value for `sbytes' to indicate "up to the end
- * of src".
- * Only vector pointers are processed, not the actual data buffers.
- */
-void qemu_iovec_concat(QEMUIOVector *dst,
- QEMUIOVector *src, size_t soffset, size_t sbytes)
-{
- qemu_iovec_concat_iov(dst, src->iov, src->niov, soffset, sbytes);
-}
-
-/*
- * Check if the contents of the iovecs are all zero
- */
-bool qemu_iovec_is_zero(QEMUIOVector *qiov)
-{
- int i;
- for (i = 0; i < qiov->niov; i++) {
- size_t offs = QEMU_ALIGN_DOWN(qiov->iov[i].iov_len, 4 * sizeof(long));
- uint8_t *ptr = qiov->iov[i].iov_base;
- if (offs && !buffer_is_zero(qiov->iov[i].iov_base, offs)) {
- return false;
- }
- for (; offs < qiov->iov[i].iov_len; offs++) {
- if (ptr[offs]) {
- return false;
- }
- }
- }
- return true;
-}
-
-void qemu_iovec_destroy(QEMUIOVector *qiov)
-{
- assert(qiov->nalloc != -1);
-
- qemu_iovec_reset(qiov);
- g_free(qiov->iov);
- qiov->nalloc = 0;
- qiov->iov = NULL;
-}
-
-void qemu_iovec_reset(QEMUIOVector *qiov)
-{
- assert(qiov->nalloc != -1);
-
- qiov->niov = 0;
- qiov->size = 0;
-}
-
-size_t qemu_iovec_to_buf(QEMUIOVector *qiov, size_t offset,
- void *buf, size_t bytes)
-{
- return iov_to_buf(qiov->iov, qiov->niov, offset, buf, bytes);
-}
-
-size_t qemu_iovec_from_buf(QEMUIOVector *qiov, size_t offset,
- const void *buf, size_t bytes)
-{
- return iov_from_buf(qiov->iov, qiov->niov, offset, buf, bytes);
-}
-
-size_t qemu_iovec_memset(QEMUIOVector *qiov, size_t offset,
- int fillc, size_t bytes)
-{
- return iov_memset(qiov->iov, qiov->niov, offset, fillc, bytes);
-}
-
-/**
- * Check that I/O vector contents are identical
- *
- * The IO vectors must have the same structure (same length of all parts).
- * A typical usage is to compare vectors created with qemu_iovec_clone().
- *
- * @a: I/O vector
- * @b: I/O vector
- * @ret: Offset to first mismatching byte or -1 if match
- */
-ssize_t qemu_iovec_compare(QEMUIOVector *a, QEMUIOVector *b)
-{
- int i;
- ssize_t offset = 0;
-
- assert(a->niov == b->niov);
- for (i = 0; i < a->niov; i++) {
- size_t len = 0;
- uint8_t *p = (uint8_t *)a->iov[i].iov_base;
- uint8_t *q = (uint8_t *)b->iov[i].iov_base;
-
- assert(a->iov[i].iov_len == b->iov[i].iov_len);
- while (len < a->iov[i].iov_len && *p++ == *q++) {
- len++;
- }
-
- offset += len;
-
- if (len != a->iov[i].iov_len) {
- return offset;
- }
- }
- return -1;
-}
-
-typedef struct {
- int src_index;
- struct iovec *src_iov;
- void *dest_base;
-} IOVectorSortElem;
-
-static int sortelem_cmp_src_base(const void *a, const void *b)
-{
- const IOVectorSortElem *elem_a = a;
- const IOVectorSortElem *elem_b = b;
-
- /* Don't overflow */
- if (elem_a->src_iov->iov_base < elem_b->src_iov->iov_base) {
- return -1;
- } else if (elem_a->src_iov->iov_base > elem_b->src_iov->iov_base) {
- return 1;
- } else {
- return 0;
- }
-}
-
-static int sortelem_cmp_src_index(const void *a, const void *b)
-{
- const IOVectorSortElem *elem_a = a;
- const IOVectorSortElem *elem_b = b;
-
- return elem_a->src_index - elem_b->src_index;
-}
-
-/**
- * Copy contents of I/O vector
- *
- * The relative relationships of overlapping iovecs are preserved. This is
- * necessary to ensure identical semantics in the cloned I/O vector.
- */
-void qemu_iovec_clone(QEMUIOVector *dest, const QEMUIOVector *src, void *buf)
-{
- IOVectorSortElem sortelems[src->niov];
- void *last_end;
- int i;
-
- /* Sort by source iovecs by base address */
- for (i = 0; i < src->niov; i++) {
- sortelems[i].src_index = i;
- sortelems[i].src_iov = &src->iov[i];
- }
- qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_base);
-
- /* Allocate buffer space taking into account overlapping iovecs */
- last_end = NULL;
- for (i = 0; i < src->niov; i++) {
- struct iovec *cur = sortelems[i].src_iov;
- ptrdiff_t rewind = 0;
-
- /* Detect overlap */
- if (last_end && last_end > cur->iov_base) {
- rewind = last_end - cur->iov_base;
- }
-
- sortelems[i].dest_base = buf - rewind;
- buf += cur->iov_len - MIN(rewind, cur->iov_len);
- last_end = MAX(cur->iov_base + cur->iov_len, last_end);
- }
-
- /* Sort by source iovec index and build destination iovec */
- qsort(sortelems, src->niov, sizeof(sortelems[0]), sortelem_cmp_src_index);
- for (i = 0; i < src->niov; i++) {
- qemu_iovec_add(dest, sortelems[i].dest_base, src->iov[i].iov_len);
- }
-}
-
-size_t iov_discard_front(struct iovec **iov, unsigned int *iov_cnt,
- size_t bytes)
-{
- size_t total = 0;
- struct iovec *cur;
-
- for (cur = *iov; *iov_cnt > 0; cur++) {
- if (cur->iov_len > bytes) {
- cur->iov_base += bytes;
- cur->iov_len -= bytes;
- total += bytes;
- break;
- }
-
- bytes -= cur->iov_len;
- total += cur->iov_len;
- *iov_cnt -= 1;
- }
-
- *iov = cur;
- return total;
-}
-
-size_t iov_discard_back(struct iovec *iov, unsigned int *iov_cnt,
- size_t bytes)
-{
- size_t total = 0;
- struct iovec *cur;
-
- if (*iov_cnt == 0) {
- return 0;
- }
-
- cur = iov + (*iov_cnt - 1);
-
- while (*iov_cnt > 0) {
- if (cur->iov_len > bytes) {
- cur->iov_len -= bytes;
- total += bytes;
- break;
- }
-
- bytes -= cur->iov_len;
- total += cur->iov_len;
- cur--;
- *iov_cnt -= 1;
- }
-
- return total;
-}
-
-void qemu_iovec_discard_back(QEMUIOVector *qiov, size_t bytes)
-{
- size_t total;
- unsigned int niov = qiov->niov;
-
- assert(qiov->size >= bytes);
- total = iov_discard_back(qiov->iov, &niov, bytes);
- assert(total == bytes);
-
- qiov->niov = niov;
- qiov->size -= bytes;
-}