* [Qemu-devel] [PATCH v2 3/4] Split struct QEMUFile out
2014-12-09 12:15 [Qemu-devel] [PATCH v2 0/4] More migration file cleanup Dr. David Alan Gilbert (git)
2014-12-09 12:15 ` [Qemu-devel] [PATCH v2 1/4] Start migrating migration code into a migration directory Dr. David Alan Gilbert (git)
2014-12-09 12:15 ` [Qemu-devel] [PATCH v2 2/4] Remove migration- pre/post fixes off files in migration/ dir Dr. David Alan Gilbert (git)
@ 2014-12-09 12:15 ` Dr. David Alan Gilbert (git)
2014-12-09 12:15 ` [Qemu-devel] [PATCH v2 4/4] Split the QEMU buffered file code out Dr. David Alan Gilbert (git)
2014-12-10 2:32 ` [Qemu-devel] [PATCH v2 0/4] More migration file cleanup Amit Shah
4 siblings, 0 replies; 7+ messages in thread
From: Dr. David Alan Gilbert (git) @ 2014-12-09 12:15 UTC (permalink / raw)
To: qemu-devel; +Cc: amit.shah, quintela
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Now we've got multiple QEMUFile source files, some of them need
access to things that were defined in qemu-file.c, so create
a -internal header for them.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
migration/qemu-file-internal.h | 53 ++++++++++++++++++++++++++++++++++++++++++
migration/qemu-file.c | 23 +-----------------
2 files changed, 54 insertions(+), 22 deletions(-)
create mode 100644 migration/qemu-file-internal.h
diff --git a/migration/qemu-file-internal.h b/migration/qemu-file-internal.h
new file mode 100644
index 0000000..d95e853
--- /dev/null
+++ b/migration/qemu-file-internal.h
@@ -0,0 +1,53 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef QEMU_FILE_INTERNAL_H
+#define QEMU_FILE_INTERNAL_H 1
+
+#include "qemu-common.h"
+#include "qemu/iov.h"
+
+#define IO_BUF_SIZE 32768
+#define MAX_IOV_SIZE MIN(IOV_MAX, 64)
+
+struct QEMUFile {
+ const QEMUFileOps *ops;
+ void *opaque;
+
+ int64_t bytes_xfer;
+ int64_t xfer_limit;
+
+ int64_t pos; /* start of buffer when writing, end of buffer
+ when reading */
+ int buf_index;
+ int buf_size; /* 0 when writing */
+ uint8_t buf[IO_BUF_SIZE];
+
+ struct iovec iov[MAX_IOV_SIZE];
+ unsigned int iovcnt;
+
+ int last_error;
+};
+
+#endif
diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index f938e36..671fba9 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -27,30 +27,9 @@
#include "block/coroutine.h"
#include "migration/migration.h"
#include "migration/qemu-file.h"
+#include "migration/qemu-file-internal.h"
#include "trace.h"
-#define IO_BUF_SIZE 32768
-#define MAX_IOV_SIZE MIN(IOV_MAX, 64)
-
-struct QEMUFile {
- const QEMUFileOps *ops;
- void *opaque;
-
- int64_t bytes_xfer;
- int64_t xfer_limit;
-
- int64_t pos; /* start of buffer when writing, end of buffer
- when reading */
- int buf_index;
- int buf_size; /* 0 when writing */
- uint8_t buf[IO_BUF_SIZE];
-
- struct iovec iov[MAX_IOV_SIZE];
- unsigned int iovcnt;
-
- int last_error;
-};
-
bool qemu_file_mode_is_not_valid(const char *mode)
{
if (mode == NULL ||
--
2.1.0
^ permalink raw reply related [flat|nested] 7+ messages in thread* [Qemu-devel] [PATCH v2 4/4] Split the QEMU buffered file code out
2014-12-09 12:15 [Qemu-devel] [PATCH v2 0/4] More migration file cleanup Dr. David Alan Gilbert (git)
` (2 preceding siblings ...)
2014-12-09 12:15 ` [Qemu-devel] [PATCH v2 3/4] Split struct QEMUFile out Dr. David Alan Gilbert (git)
@ 2014-12-09 12:15 ` Dr. David Alan Gilbert (git)
2014-12-10 2:32 ` [Qemu-devel] [PATCH v2 0/4] More migration file cleanup Amit Shah
4 siblings, 0 replies; 7+ messages in thread
From: Dr. David Alan Gilbert (git) @ 2014-12-09 12:15 UTC (permalink / raw)
To: qemu-devel; +Cc: amit.shah, quintela
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
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>
---
migration/Makefile.objs | 2 +-
migration/qemu-file-buf.c | 486 ++++++++++++++++++++++++++++++++++++++++++++++
migration/qemu-file.c | 455 -------------------------------------------
tests/Makefile | 3 +-
4 files changed, 489 insertions(+), 457 deletions(-)
create mode 100644 migration/qemu-file-buf.c
diff --git a/migration/Makefile.objs b/migration/Makefile.objs
index ce1e3c7..d929e96 100644
--- a/migration/Makefile.objs
+++ b/migration/Makefile.objs
@@ -1,6 +1,6 @@
common-obj-y += migration.o tcp.o
common-obj-y += vmstate.o
-common-obj-y += qemu-file.o qemu-file-unix.o qemu-file-stdio.o
+common-obj-y += qemu-file.o qemu-file-buf.o qemu-file-unix.o qemu-file-stdio.o
common-obj-y += xbzrle.o
common-obj-$(CONFIG_RDMA) += rdma.o
diff --git a/migration/qemu-file-buf.c b/migration/qemu-file-buf.c
new file mode 100644
index 0000000..d33dd44
--- /dev/null
+++ b/migration/qemu-file-buf.c
@@ -0,0 +1,486 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "qemu-common.h"
+#include "qemu/iov.h"
+#include "qemu/sockets.h"
+#include "block/coroutine.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "migration/qemu-file-internal.h"
+#include "trace.h"
+
+#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;
+}
diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index 671fba9..d2d4007 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;
-}
diff --git a/tests/Makefile b/tests/Makefile
index 3a03979..3f4c0d7 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -258,7 +258,8 @@ 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 :\
--
2.1.0
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