Hi,
Does this document update make sense?
Regards,
Jay
On 2017/11/23 16:47, Jay Zhou wrote:
Since the commit 11808bb0c422134bf09119f4aa22c59b0ce84bf3 removed
the put_buffer callback and using an iovec based write handler instead,
the docs should be sync with the code too.
Signed-off-by: Jay Zhou <jianjay.z...@huawei.com>
---
docs/devel/migration.txt | 31 ++++++++++++++++++-------------
1 file changed, 18 insertions(+), 13 deletions(-)
diff --git a/docs/devel/migration.txt b/docs/devel/migration.txt
index 4030703..e7b08c9 100644
--- a/docs/devel/migration.txt
+++ b/docs/devel/migration.txt
@@ -52,26 +52,31 @@ QEMU uses a QEMUFile abstraction to be able to do
migration. Any type
of migration that wants to use QEMU infrastructure has to create a
QEMUFile with:
-QEMUFile *qemu_fopen_ops(void *opaque,
- QEMUFilePutBufferFunc *put_buffer,
- QEMUFileGetBufferFunc *get_buffer,
- QEMUFileCloseFunc *close);
+typedef struct QEMUFileOps {
+ QEMUFileGetBufferFunc *get_buffer;
+ QEMUFileCloseFunc *close;
+ QEMUFileSetBlocking *set_blocking;
+ QEMUFileWritevBufferFunc *writev_buffer;
+ QEMURetPathFunc *get_return_path;
+ QEMUFileShutdownFunc *shut_down;
+} QEMUFileOps;
-The functions have the following functionality:
+QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops);
-This function writes a chunk of data to a file at the given position.
-The pos argument can be ignored if the file is only used for
-streaming. The handler should try to write all of the data it can.
+The main functions of QEMUFileOps have the following functionality:
-typedef int (QEMUFilePutBufferFunc)(void *opaque, const uint8_t *buf,
- int64_t pos, int size);
+This function writes an iovec to file. The handler must write all
+of the data or return a negative errno value.
+
+typedef ssize_t (QEMUFileWritevBufferFunc)(void *opaque, struct iovec *iov,
+ int iovcnt, int64_t pos);
Read a chunk of data from a file at the given position. The pos argument
can be ignored if the file is only be used for streaming. The number of
bytes actually read should be returned.
-typedef int (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
- int64_t pos, int size);
+typedef ssize_t (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
+ int64_t pos, int size);
Close a file and return an error code.
@@ -80,7 +85,7 @@ typedef int (QEMUFileCloseFunc)(void *opaque);
You can use any internal state that you need using the opaque void *
pointer that is passed to all functions.
-The important functions for us are put_buffer()/get_buffer() that
+The important functions for us are writev_buffer()/get_buffer() that
allow to write/read a buffer into the QEMUFile.
=== How to save the state of one device ===
