Split the QEMU buffered file code out
The splitting of qemu-file and addition of the buffered file landed at the same time; so now split the buffered file code out. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
This commit is contained in:
Dr. David Alan Gilbert
Amit Shah
parent
4f9d090012
commit
977184db39
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@ -1,6 +1,6 @@
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common-obj-y += migration.o tcp.o
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common-obj-y += vmstate.o
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common-obj-y += qemu-file.o qemu-file-unix.o qemu-file-stdio.o
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common-obj-y += qemu-file.o qemu-file-buf.o qemu-file-unix.o qemu-file-stdio.o
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common-obj-y += xbzrle.o
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common-obj-$(CONFIG_RDMA) += rdma.o
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@ -0,0 +1,486 @@
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/*
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* QEMU System Emulator
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*
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* Copyright (c) 2003-2008 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h"
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#include "qemu/iov.h"
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#include "qemu/sockets.h"
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#include "block/coroutine.h"
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#include "migration/migration.h"
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#include "migration/qemu-file.h"
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#include "migration/qemu-file-internal.h"
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#include "trace.h"
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#define QSB_CHUNK_SIZE (1 << 10)
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#define QSB_MAX_CHUNK_SIZE (16 * QSB_CHUNK_SIZE)
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/**
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* Create a QEMUSizedBuffer
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* This type of buffer uses scatter-gather lists internally and
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* can grow to any size. Any data array in the scatter-gather list
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* can hold different amount of bytes.
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*
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* @buffer: Optional buffer to copy into the QSB
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* @len: size of initial buffer; if @buffer is given, buffer must
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* hold at least len bytes
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*
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* Returns a pointer to a QEMUSizedBuffer or NULL on allocation failure
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*/
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QEMUSizedBuffer *qsb_create(const uint8_t *buffer, size_t len)
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{
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QEMUSizedBuffer *qsb;
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size_t alloc_len, num_chunks, i, to_copy;
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size_t chunk_size = (len > QSB_MAX_CHUNK_SIZE)
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? QSB_MAX_CHUNK_SIZE
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: QSB_CHUNK_SIZE;
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num_chunks = DIV_ROUND_UP(len ? len : QSB_CHUNK_SIZE, chunk_size);
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alloc_len = num_chunks * chunk_size;
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qsb = g_try_new0(QEMUSizedBuffer, 1);
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if (!qsb) {
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return NULL;
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}
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qsb->iov = g_try_new0(struct iovec, num_chunks);
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if (!qsb->iov) {
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g_free(qsb);
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return NULL;
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}
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qsb->n_iov = num_chunks;
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for (i = 0; i < num_chunks; i++) {
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qsb->iov[i].iov_base = g_try_malloc0(chunk_size);
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if (!qsb->iov[i].iov_base) {
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/* qsb_free is safe since g_free can cope with NULL */
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qsb_free(qsb);
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return NULL;
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}
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qsb->iov[i].iov_len = chunk_size;
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if (buffer) {
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to_copy = (len - qsb->used) > chunk_size
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? chunk_size : (len - qsb->used);
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memcpy(qsb->iov[i].iov_base, &buffer[qsb->used], to_copy);
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qsb->used += to_copy;
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}
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}
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qsb->size = alloc_len;
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return qsb;
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}
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/**
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* Free the QEMUSizedBuffer
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*
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* @qsb: The QEMUSizedBuffer to free
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*/
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void qsb_free(QEMUSizedBuffer *qsb)
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{
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size_t i;
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if (!qsb) {
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return;
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}
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for (i = 0; i < qsb->n_iov; i++) {
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g_free(qsb->iov[i].iov_base);
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}
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g_free(qsb->iov);
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g_free(qsb);
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}
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/**
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* Get the number of used bytes in the QEMUSizedBuffer
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*
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* @qsb: A QEMUSizedBuffer
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*
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* Returns the number of bytes currently used in this buffer
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*/
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size_t qsb_get_length(const QEMUSizedBuffer *qsb)
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{
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return qsb->used;
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}
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/**
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* Set the length of the buffer; the primary usage of this
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* function is to truncate the number of used bytes in the buffer.
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* The size will not be extended beyond the current number of
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* allocated bytes in the QEMUSizedBuffer.
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*
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* @qsb: A QEMUSizedBuffer
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* @new_len: The new length of bytes in the buffer
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*
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* Returns the number of bytes the buffer was truncated or extended
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* to.
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*/
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size_t qsb_set_length(QEMUSizedBuffer *qsb, size_t new_len)
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{
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if (new_len <= qsb->size) {
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qsb->used = new_len;
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} else {
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qsb->used = qsb->size;
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}
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return qsb->used;
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}
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/**
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* Get the iovec that holds the data for a given position @pos.
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*
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* @qsb: A QEMUSizedBuffer
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* @pos: The index of a byte in the buffer
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* @d_off: Pointer to an offset that this function will indicate
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* at what position within the returned iovec the byte
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* is to be found
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*
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* Returns the index of the iovec that holds the byte at the given
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* index @pos in the byte stream; a negative number if the iovec
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* for the given position @pos does not exist.
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*/
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static ssize_t qsb_get_iovec(const QEMUSizedBuffer *qsb,
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off_t pos, off_t *d_off)
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{
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ssize_t i;
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off_t curr = 0;
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if (pos > qsb->used) {
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return -1;
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}
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for (i = 0; i < qsb->n_iov; i++) {
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if (curr + qsb->iov[i].iov_len > pos) {
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*d_off = pos - curr;
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return i;
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}
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curr += qsb->iov[i].iov_len;
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}
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return -1;
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}
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/*
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* Convert the QEMUSizedBuffer into a flat buffer.
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*
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* Note: If at all possible, try to avoid this function since it
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* may unnecessarily copy memory around.
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*
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* @qsb: pointer to QEMUSizedBuffer
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* @start: offset to start at
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* @count: number of bytes to copy
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* @buf: a pointer to a buffer to write into (at least @count bytes)
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*
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* Returns the number of bytes copied into the output buffer
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*/
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ssize_t qsb_get_buffer(const QEMUSizedBuffer *qsb, off_t start,
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size_t count, uint8_t *buffer)
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{
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const struct iovec *iov;
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size_t to_copy, all_copy;
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ssize_t index;
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off_t s_off;
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off_t d_off = 0;
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char *s;
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if (start > qsb->used) {
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return 0;
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}
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all_copy = qsb->used - start;
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if (all_copy > count) {
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all_copy = count;
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} else {
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count = all_copy;
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}
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index = qsb_get_iovec(qsb, start, &s_off);
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if (index < 0) {
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return 0;
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}
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while (all_copy > 0) {
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iov = &qsb->iov[index];
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s = iov->iov_base;
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to_copy = iov->iov_len - s_off;
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if (to_copy > all_copy) {
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to_copy = all_copy;
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}
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memcpy(&buffer[d_off], &s[s_off], to_copy);
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d_off += to_copy;
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all_copy -= to_copy;
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s_off = 0;
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index++;
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}
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return count;
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}
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/**
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* Grow the QEMUSizedBuffer to the given size and allocate
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* memory for it.
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*
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* @qsb: A QEMUSizedBuffer
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* @new_size: The new size of the buffer
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*
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* Return:
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* a negative error code in case of memory allocation failure
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* or
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* the new size of the buffer. The returned size may be greater or equal
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* to @new_size.
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*/
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static ssize_t qsb_grow(QEMUSizedBuffer *qsb, size_t new_size)
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{
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size_t needed_chunks, i;
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if (qsb->size < new_size) {
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struct iovec *new_iov;
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size_t size_diff = new_size - qsb->size;
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size_t chunk_size = (size_diff > QSB_MAX_CHUNK_SIZE)
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? QSB_MAX_CHUNK_SIZE : QSB_CHUNK_SIZE;
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needed_chunks = DIV_ROUND_UP(size_diff, chunk_size);
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new_iov = g_try_new(struct iovec, qsb->n_iov + needed_chunks);
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if (new_iov == NULL) {
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return -ENOMEM;
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}
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/* Allocate new chunks as needed into new_iov */
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for (i = qsb->n_iov; i < qsb->n_iov + needed_chunks; i++) {
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new_iov[i].iov_base = g_try_malloc0(chunk_size);
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new_iov[i].iov_len = chunk_size;
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if (!new_iov[i].iov_base) {
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size_t j;
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/* Free previously allocated new chunks */
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for (j = qsb->n_iov; j < i; j++) {
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g_free(new_iov[j].iov_base);
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}
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g_free(new_iov);
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return -ENOMEM;
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}
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}
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/*
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* Now we can't get any allocation errors, copy over to new iov
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* and switch.
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*/
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for (i = 0; i < qsb->n_iov; i++) {
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new_iov[i] = qsb->iov[i];
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}
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qsb->n_iov += needed_chunks;
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g_free(qsb->iov);
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qsb->iov = new_iov;
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qsb->size += (needed_chunks * chunk_size);
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}
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return qsb->size;
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}
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/**
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* Write into the QEMUSizedBuffer at a given position and a given
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* number of bytes. This function will automatically grow the
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* QEMUSizedBuffer.
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*
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* @qsb: A QEMUSizedBuffer
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* @source: A byte array to copy data from
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* @pos: The position within the @qsb to write data to
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* @size: The number of bytes to copy into the @qsb
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*
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* Returns @size or a negative error code in case of memory allocation failure,
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* or with an invalid 'pos'
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*/
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ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *source,
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off_t pos, size_t count)
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{
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ssize_t rc = qsb_grow(qsb, pos + count);
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size_t to_copy;
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size_t all_copy = count;
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const struct iovec *iov;
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ssize_t index;
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char *dest;
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off_t d_off, s_off = 0;
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if (rc < 0) {
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return rc;
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}
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if (pos + count > qsb->used) {
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qsb->used = pos + count;
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}
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index = qsb_get_iovec(qsb, pos, &d_off);
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if (index < 0) {
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return -EINVAL;
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}
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while (all_copy > 0) {
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iov = &qsb->iov[index];
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dest = iov->iov_base;
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to_copy = iov->iov_len - d_off;
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if (to_copy > all_copy) {
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to_copy = all_copy;
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}
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memcpy(&dest[d_off], &source[s_off], to_copy);
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s_off += to_copy;
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all_copy -= to_copy;
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d_off = 0;
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index++;
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}
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return count;
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}
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/**
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* Create a deep copy of the given QEMUSizedBuffer.
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*
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* @qsb: A QEMUSizedBuffer
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*
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* Returns a clone of @qsb or NULL on allocation failure
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*/
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QEMUSizedBuffer *qsb_clone(const QEMUSizedBuffer *qsb)
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{
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QEMUSizedBuffer *out = qsb_create(NULL, qsb_get_length(qsb));
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size_t i;
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ssize_t res;
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off_t pos = 0;
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if (!out) {
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return NULL;
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}
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for (i = 0; i < qsb->n_iov; i++) {
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res = qsb_write_at(out, qsb->iov[i].iov_base,
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pos, qsb->iov[i].iov_len);
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if (res < 0) {
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qsb_free(out);
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return NULL;
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}
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pos += res;
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}
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return out;
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}
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typedef struct QEMUBuffer {
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QEMUSizedBuffer *qsb;
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QEMUFile *file;
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} QEMUBuffer;
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static int buf_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
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{
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QEMUBuffer *s = opaque;
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ssize_t len = qsb_get_length(s->qsb) - pos;
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if (len <= 0) {
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return 0;
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}
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if (len > size) {
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len = size;
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}
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return qsb_get_buffer(s->qsb, pos, len, buf);
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}
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static int buf_put_buffer(void *opaque, const uint8_t *buf,
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int64_t pos, int size)
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{
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QEMUBuffer *s = opaque;
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return qsb_write_at(s->qsb, buf, pos, size);
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}
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static int buf_close(void *opaque)
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{
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QEMUBuffer *s = opaque;
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qsb_free(s->qsb);
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g_free(s);
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return 0;
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}
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const QEMUSizedBuffer *qemu_buf_get(QEMUFile *f)
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{
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QEMUBuffer *p;
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qemu_fflush(f);
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p = f->opaque;
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return p->qsb;
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}
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static const QEMUFileOps buf_read_ops = {
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.get_buffer = buf_get_buffer,
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.close = buf_close,
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};
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static const QEMUFileOps buf_write_ops = {
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.put_buffer = buf_put_buffer,
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.close = buf_close,
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};
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QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input)
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{
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QEMUBuffer *s;
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if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') ||
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mode[1] != '\0') {
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error_report("qemu_bufopen: Argument validity check failed");
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return NULL;
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}
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s = g_malloc0(sizeof(QEMUBuffer));
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||||
if (mode[0] == 'r') {
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s->qsb = input;
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||||
}
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||||
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if (s->qsb == NULL) {
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s->qsb = qsb_create(NULL, 0);
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}
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if (!s->qsb) {
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g_free(s);
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error_report("qemu_bufopen: qsb_create failed");
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return NULL;
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}
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if (mode[0] == 'r') {
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s->file = qemu_fopen_ops(s, &buf_read_ops);
|
||||
} else {
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s->file = qemu_fopen_ops(s, &buf_write_ops);
|
||||
}
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return s->file;
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}
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||||
|
|
@ -517,458 +517,3 @@ uint64_t qemu_get_be64(QEMUFile *f)
|
|||
v |= qemu_get_be32(f);
|
||||
return v;
|
||||
}
|
||||
|
||||
#define QSB_CHUNK_SIZE (1 << 10)
|
||||
#define QSB_MAX_CHUNK_SIZE (16 * QSB_CHUNK_SIZE)
|
||||
|
||||
/**
|
||||
* Create a QEMUSizedBuffer
|
||||
* This type of buffer uses scatter-gather lists internally and
|
||||
* can grow to any size. Any data array in the scatter-gather list
|
||||
* can hold different amount of bytes.
|
||||
*
|
||||
* @buffer: Optional buffer to copy into the QSB
|
||||
* @len: size of initial buffer; if @buffer is given, buffer must
|
||||
* hold at least len bytes
|
||||
*
|
||||
* Returns a pointer to a QEMUSizedBuffer or NULL on allocation failure
|
||||
*/
|
||||
QEMUSizedBuffer *qsb_create(const uint8_t *buffer, size_t len)
|
||||
{
|
||||
QEMUSizedBuffer *qsb;
|
||||
size_t alloc_len, num_chunks, i, to_copy;
|
||||
size_t chunk_size = (len > QSB_MAX_CHUNK_SIZE)
|
||||
? QSB_MAX_CHUNK_SIZE
|
||||
: QSB_CHUNK_SIZE;
|
||||
|
||||
num_chunks = DIV_ROUND_UP(len ? len : QSB_CHUNK_SIZE, chunk_size);
|
||||
alloc_len = num_chunks * chunk_size;
|
||||
|
||||
qsb = g_try_new0(QEMUSizedBuffer, 1);
|
||||
if (!qsb) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
qsb->iov = g_try_new0(struct iovec, num_chunks);
|
||||
if (!qsb->iov) {
|
||||
g_free(qsb);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
qsb->n_iov = num_chunks;
|
||||
|
||||
for (i = 0; i < num_chunks; i++) {
|
||||
qsb->iov[i].iov_base = g_try_malloc0(chunk_size);
|
||||
if (!qsb->iov[i].iov_base) {
|
||||
/* qsb_free is safe since g_free can cope with NULL */
|
||||
qsb_free(qsb);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
qsb->iov[i].iov_len = chunk_size;
|
||||
if (buffer) {
|
||||
to_copy = (len - qsb->used) > chunk_size
|
||||
? chunk_size : (len - qsb->used);
|
||||
memcpy(qsb->iov[i].iov_base, &buffer[qsb->used], to_copy);
|
||||
qsb->used += to_copy;
|
||||
}
|
||||
}
|
||||
|
||||
qsb->size = alloc_len;
|
||||
|
||||
return qsb;
|
||||
}
|
||||
|
||||
/**
|
||||
* Free the QEMUSizedBuffer
|
||||
*
|
||||
* @qsb: The QEMUSizedBuffer to free
|
||||
*/
|
||||
void qsb_free(QEMUSizedBuffer *qsb)
|
||||
{
|
||||
size_t i;
|
||||
|
||||
if (!qsb) {
|
||||
return;
|
||||
}
|
||||
|
||||
for (i = 0; i < qsb->n_iov; i++) {
|
||||
g_free(qsb->iov[i].iov_base);
|
||||
}
|
||||
g_free(qsb->iov);
|
||||
g_free(qsb);
|
||||
}
|
||||
|
||||
/**
|
||||
* Get the number of used bytes in the QEMUSizedBuffer
|
||||
*
|
||||
* @qsb: A QEMUSizedBuffer
|
||||
*
|
||||
* Returns the number of bytes currently used in this buffer
|
||||
*/
|
||||
size_t qsb_get_length(const QEMUSizedBuffer *qsb)
|
||||
{
|
||||
return qsb->used;
|
||||
}
|
||||
|
||||
/**
|
||||
* Set the length of the buffer; the primary usage of this
|
||||
* function is to truncate the number of used bytes in the buffer.
|
||||
* The size will not be extended beyond the current number of
|
||||
* allocated bytes in the QEMUSizedBuffer.
|
||||
*
|
||||
* @qsb: A QEMUSizedBuffer
|
||||
* @new_len: The new length of bytes in the buffer
|
||||
*
|
||||
* Returns the number of bytes the buffer was truncated or extended
|
||||
* to.
|
||||
*/
|
||||
size_t qsb_set_length(QEMUSizedBuffer *qsb, size_t new_len)
|
||||
{
|
||||
if (new_len <= qsb->size) {
|
||||
qsb->used = new_len;
|
||||
} else {
|
||||
qsb->used = qsb->size;
|
||||
}
|
||||
return qsb->used;
|
||||
}
|
||||
|
||||
/**
|
||||
* Get the iovec that holds the data for a given position @pos.
|
||||
*
|
||||
* @qsb: A QEMUSizedBuffer
|
||||
* @pos: The index of a byte in the buffer
|
||||
* @d_off: Pointer to an offset that this function will indicate
|
||||
* at what position within the returned iovec the byte
|
||||
* is to be found
|
||||
*
|
||||
* Returns the index of the iovec that holds the byte at the given
|
||||
* index @pos in the byte stream; a negative number if the iovec
|
||||
* for the given position @pos does not exist.
|
||||
*/
|
||||
static ssize_t qsb_get_iovec(const QEMUSizedBuffer *qsb,
|
||||
off_t pos, off_t *d_off)
|
||||
{
|
||||
ssize_t i;
|
||||
off_t curr = 0;
|
||||
|
||||
if (pos > qsb->used) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
for (i = 0; i < qsb->n_iov; i++) {
|
||||
if (curr + qsb->iov[i].iov_len > pos) {
|
||||
*d_off = pos - curr;
|
||||
return i;
|
||||
}
|
||||
curr += qsb->iov[i].iov_len;
|
||||
}
|
||||
return -1;
|
||||
}
|
||||
|
||||
/*
|
||||
* Convert the QEMUSizedBuffer into a flat buffer.
|
||||
*
|
||||
* Note: If at all possible, try to avoid this function since it
|
||||
* may unnecessarily copy memory around.
|
||||
*
|
||||
* @qsb: pointer to QEMUSizedBuffer
|
||||
* @start: offset to start at
|
||||
* @count: number of bytes to copy
|
||||
* @buf: a pointer to a buffer to write into (at least @count bytes)
|
||||
*
|
||||
* Returns the number of bytes copied into the output buffer
|
||||
*/
|
||||
ssize_t qsb_get_buffer(const QEMUSizedBuffer *qsb, off_t start,
|
||||
size_t count, uint8_t *buffer)
|
||||
{
|
||||
const struct iovec *iov;
|
||||
size_t to_copy, all_copy;
|
||||
ssize_t index;
|
||||
off_t s_off;
|
||||
off_t d_off = 0;
|
||||
char *s;
|
||||
|
||||
if (start > qsb->used) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
all_copy = qsb->used - start;
|
||||
if (all_copy > count) {
|
||||
all_copy = count;
|
||||
} else {
|
||||
count = all_copy;
|
||||
}
|
||||
|
||||
index = qsb_get_iovec(qsb, start, &s_off);
|
||||
if (index < 0) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
while (all_copy > 0) {
|
||||
iov = &qsb->iov[index];
|
||||
|
||||
s = iov->iov_base;
|
||||
|
||||
to_copy = iov->iov_len - s_off;
|
||||
if (to_copy > all_copy) {
|
||||
to_copy = all_copy;
|
||||
}
|
||||
memcpy(&buffer[d_off], &s[s_off], to_copy);
|
||||
|
||||
d_off += to_copy;
|
||||
all_copy -= to_copy;
|
||||
|
||||
s_off = 0;
|
||||
index++;
|
||||
}
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
/**
|
||||
* Grow the QEMUSizedBuffer to the given size and allocate
|
||||
* memory for it.
|
||||
*
|
||||
* @qsb: A QEMUSizedBuffer
|
||||
* @new_size: The new size of the buffer
|
||||
*
|
||||
* Return:
|
||||
* a negative error code in case of memory allocation failure
|
||||
* or
|
||||
* the new size of the buffer. The returned size may be greater or equal
|
||||
* to @new_size.
|
||||
*/
|
||||
static ssize_t qsb_grow(QEMUSizedBuffer *qsb, size_t new_size)
|
||||
{
|
||||
size_t needed_chunks, i;
|
||||
|
||||
if (qsb->size < new_size) {
|
||||
struct iovec *new_iov;
|
||||
size_t size_diff = new_size - qsb->size;
|
||||
size_t chunk_size = (size_diff > QSB_MAX_CHUNK_SIZE)
|
||||
? QSB_MAX_CHUNK_SIZE : QSB_CHUNK_SIZE;
|
||||
|
||||
needed_chunks = DIV_ROUND_UP(size_diff, chunk_size);
|
||||
|
||||
new_iov = g_try_new(struct iovec, qsb->n_iov + needed_chunks);
|
||||
if (new_iov == NULL) {
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
/* Allocate new chunks as needed into new_iov */
|
||||
for (i = qsb->n_iov; i < qsb->n_iov + needed_chunks; i++) {
|
||||
new_iov[i].iov_base = g_try_malloc0(chunk_size);
|
||||
new_iov[i].iov_len = chunk_size;
|
||||
if (!new_iov[i].iov_base) {
|
||||
size_t j;
|
||||
|
||||
/* Free previously allocated new chunks */
|
||||
for (j = qsb->n_iov; j < i; j++) {
|
||||
g_free(new_iov[j].iov_base);
|
||||
}
|
||||
g_free(new_iov);
|
||||
|
||||
return -ENOMEM;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Now we can't get any allocation errors, copy over to new iov
|
||||
* and switch.
|
||||
*/
|
||||
for (i = 0; i < qsb->n_iov; i++) {
|
||||
new_iov[i] = qsb->iov[i];
|
||||
}
|
||||
|
||||
qsb->n_iov += needed_chunks;
|
||||
g_free(qsb->iov);
|
||||
qsb->iov = new_iov;
|
||||
qsb->size += (needed_chunks * chunk_size);
|
||||
}
|
||||
|
||||
return qsb->size;
|
||||
}
|
||||
|
||||
/**
|
||||
* Write into the QEMUSizedBuffer at a given position and a given
|
||||
* number of bytes. This function will automatically grow the
|
||||
* QEMUSizedBuffer.
|
||||
*
|
||||
* @qsb: A QEMUSizedBuffer
|
||||
* @source: A byte array to copy data from
|
||||
* @pos: The position within the @qsb to write data to
|
||||
* @size: The number of bytes to copy into the @qsb
|
||||
*
|
||||
* Returns @size or a negative error code in case of memory allocation failure,
|
||||
* or with an invalid 'pos'
|
||||
*/
|
||||
ssize_t qsb_write_at(QEMUSizedBuffer *qsb, const uint8_t *source,
|
||||
off_t pos, size_t count)
|
||||
{
|
||||
ssize_t rc = qsb_grow(qsb, pos + count);
|
||||
size_t to_copy;
|
||||
size_t all_copy = count;
|
||||
const struct iovec *iov;
|
||||
ssize_t index;
|
||||
char *dest;
|
||||
off_t d_off, s_off = 0;
|
||||
|
||||
if (rc < 0) {
|
||||
return rc;
|
||||
}
|
||||
|
||||
if (pos + count > qsb->used) {
|
||||
qsb->used = pos + count;
|
||||
}
|
||||
|
||||
index = qsb_get_iovec(qsb, pos, &d_off);
|
||||
if (index < 0) {
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
while (all_copy > 0) {
|
||||
iov = &qsb->iov[index];
|
||||
|
||||
dest = iov->iov_base;
|
||||
|
||||
to_copy = iov->iov_len - d_off;
|
||||
if (to_copy > all_copy) {
|
||||
to_copy = all_copy;
|
||||
}
|
||||
|
||||
memcpy(&dest[d_off], &source[s_off], to_copy);
|
||||
|
||||
s_off += to_copy;
|
||||
all_copy -= to_copy;
|
||||
|
||||
d_off = 0;
|
||||
index++;
|
||||
}
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a deep copy of the given QEMUSizedBuffer.
|
||||
*
|
||||
* @qsb: A QEMUSizedBuffer
|
||||
*
|
||||
* Returns a clone of @qsb or NULL on allocation failure
|
||||
*/
|
||||
QEMUSizedBuffer *qsb_clone(const QEMUSizedBuffer *qsb)
|
||||
{
|
||||
QEMUSizedBuffer *out = qsb_create(NULL, qsb_get_length(qsb));
|
||||
size_t i;
|
||||
ssize_t res;
|
||||
off_t pos = 0;
|
||||
|
||||
if (!out) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
for (i = 0; i < qsb->n_iov; i++) {
|
||||
res = qsb_write_at(out, qsb->iov[i].iov_base,
|
||||
pos, qsb->iov[i].iov_len);
|
||||
if (res < 0) {
|
||||
qsb_free(out);
|
||||
return NULL;
|
||||
}
|
||||
pos += res;
|
||||
}
|
||||
|
||||
return out;
|
||||
}
|
||||
|
||||
typedef struct QEMUBuffer {
|
||||
QEMUSizedBuffer *qsb;
|
||||
QEMUFile *file;
|
||||
} QEMUBuffer;
|
||||
|
||||
static int buf_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
|
||||
{
|
||||
QEMUBuffer *s = opaque;
|
||||
ssize_t len = qsb_get_length(s->qsb) - pos;
|
||||
|
||||
if (len <= 0) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (len > size) {
|
||||
len = size;
|
||||
}
|
||||
return qsb_get_buffer(s->qsb, pos, len, buf);
|
||||
}
|
||||
|
||||
static int buf_put_buffer(void *opaque, const uint8_t *buf,
|
||||
int64_t pos, int size)
|
||||
{
|
||||
QEMUBuffer *s = opaque;
|
||||
|
||||
return qsb_write_at(s->qsb, buf, pos, size);
|
||||
}
|
||||
|
||||
static int buf_close(void *opaque)
|
||||
{
|
||||
QEMUBuffer *s = opaque;
|
||||
|
||||
qsb_free(s->qsb);
|
||||
|
||||
g_free(s);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
const QEMUSizedBuffer *qemu_buf_get(QEMUFile *f)
|
||||
{
|
||||
QEMUBuffer *p;
|
||||
|
||||
qemu_fflush(f);
|
||||
|
||||
p = f->opaque;
|
||||
|
||||
return p->qsb;
|
||||
}
|
||||
|
||||
static const QEMUFileOps buf_read_ops = {
|
||||
.get_buffer = buf_get_buffer,
|
||||
.close = buf_close,
|
||||
};
|
||||
|
||||
static const QEMUFileOps buf_write_ops = {
|
||||
.put_buffer = buf_put_buffer,
|
||||
.close = buf_close,
|
||||
};
|
||||
|
||||
QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input)
|
||||
{
|
||||
QEMUBuffer *s;
|
||||
|
||||
if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') ||
|
||||
mode[1] != '\0') {
|
||||
error_report("qemu_bufopen: Argument validity check failed");
|
||||
return NULL;
|
||||
}
|
||||
|
||||
s = g_malloc0(sizeof(QEMUBuffer));
|
||||
if (mode[0] == 'r') {
|
||||
s->qsb = input;
|
||||
}
|
||||
|
||||
if (s->qsb == NULL) {
|
||||
s->qsb = qsb_create(NULL, 0);
|
||||
}
|
||||
if (!s->qsb) {
|
||||
g_free(s);
|
||||
error_report("qemu_bufopen: qsb_create failed");
|
||||
return NULL;
|
||||
}
|
||||
|
||||
|
||||
if (mode[0] == 'r') {
|
||||
s->file = qemu_fopen_ops(s, &buf_read_ops);
|
||||
} else {
|
||||
s->file = qemu_fopen_ops(s, &buf_write_ops);
|
||||
}
|
||||
return s->file;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -260,7 +260,8 @@ tests/test-qdev-global-props$(EXESUF): tests/test-qdev-global-props.o \
|
|||
$(test-qapi-obj-y) \
|
||||
libqemuutil.a libqemustub.a
|
||||
tests/test-vmstate$(EXESUF): tests/test-vmstate.o \
|
||||
migration/vmstate.o migration/qemu-file.o migration/qemu-file-unix.o \
|
||||
migration/vmstate.o migration/qemu-file.o migration/qemu-file-buf.o \
|
||||
migration/qemu-file-unix.o \
|
||||
libqemuutil.a libqemustub.a
|
||||
|
||||
tests/test-qapi-types.c tests/test-qapi-types.h :\
|
||||
|
|
|
|||
Loading…
Reference in New Issue