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-rw-r--r--migration/qemu-file.c455
1 files changed, 0 insertions, 455 deletions
diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index 671fba988a..d2d40073f0 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -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;
-}
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-03 20:29:43 +0000