Message ID | 1418347746-15829-5-git-send-email-liang.z.li@intel.com |
---|---|
State | New |
Headers | show |
* Liang Li (liang.z.li@intel.com) wrote: > migrate_qemu_add_compression_data() compress the data > and put it to QEMUFile. migrate_qemu_flush() put the > data in the source QEMUFile to destination QEMUFile. > > The two function can help to do live migration. Typo in the title 'tow->two' - but perhaps a better title would be 'Add compression functions to QEMUFile' > Signed-off-by: Liang Li <liang.z.li@intel.com> > Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> > --- > include/migration/qemu-file.h | 3 +++ > qemu-file.c | 32 ++++++++++++++++++++++++++++++++ > 2 files changed, 35 insertions(+) > > diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h > index 401676b..d70fb8d 100644 > --- a/include/migration/qemu-file.h > +++ b/include/migration/qemu-file.h > @@ -150,6 +150,9 @@ void qemu_put_be32(QEMUFile *f, unsigned int v); > void qemu_put_be64(QEMUFile *f, uint64_t v); > int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset); > int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size); > +size_t migrate_qemu_add_compression_data(QEMUFile *f, > + const uint8_t *p, size_t size, int level); > +int migrate_qemu_flush(QEMUFile *f_des, QEMUFile *f_src); > /* > * Note that you can only peek continuous bytes from where the current pointer > * is; you aren't guaranteed to be able to peak to +n bytes unless you've > diff --git a/qemu-file.c b/qemu-file.c > index f938e36..2668ad0 100644 > --- a/qemu-file.c > +++ b/qemu-file.c > @@ -21,6 +21,7 @@ > * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN > * THE SOFTWARE. > */ > +#include <zlib.h> > #include "qemu-common.h" > #include "qemu/iov.h" > #include "qemu/sockets.h" > @@ -993,3 +994,34 @@ QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input) > } > return s->file; > } > + > +/* compress size bytes of data start at p with specific compression > + * leve and store the compressed data to the buffer of f. > + */ > + > +size_t migrate_qemu_add_compression_data(QEMUFile *f, > + const uint8_t *p, size_t size, int level) It's an odd name, QEMUFile is only used by migration anyway; maybe qemufile_add_compression_data ? > +{ > + size_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int); > + > + if (compress2(f->buf + f->buf_index + sizeof(int), &blen, (Bytef *)p, > + size, level) != Z_OK) { > + error_report("Compress Failed!"); > + return 0; > + } What are the 'sizeof(int)'s for? It's unusual because we normally keep the format of the stream the same even if one side was a 32bit qemu and the other 64bit. How do you know that there is enough space for the compress - i.e. what happens if f->buf_index is too high? > + qemu_put_be32(f, blen); > + f->buf_index += blen; > + return blen + sizeof(int); > +} > + > +int migrate_qemu_flush(QEMUFile *f_des, QEMUFile *f_src) > +{ > + int len = 0; > + > + if (f_src->buf_index > 0) { > + len = f_src->buf_index; > + qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); > + f_src->buf_index = 0; > + } > + return len; > +} Can you explain a bit more here how you're using the src file; I think you're using it as kind of a dummy buffer; but it needs to be documented somewhere. Again I'm also not sure of the name of this function. Dave > -- > 1.8.3.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> > +size_t migrate_qemu_add_compression_data(QEMUFile *f, > > + const uint8_t *p, size_t size, int level) > > It's an odd name, QEMUFile is only used by migration anyway; maybe > qemufile_add_compression_data ? > > > +{ > > + size_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int); > > + > > + if (compress2(f->buf + f->buf_index + sizeof(int), &blen, (Bytef *)p, > > + size, level) != Z_OK) { > > + error_report("Compress Failed!"); > > + return 0; > > + } > > What are the 'sizeof(int)'s for? It's unusual because we normally keep the > format of the stream the same even if one side was a 32bit qemu and the > other 64bit. > How do you know that there is enough space for the compress - i.e. what > happens if f->buf_index is too high? The compress2 will return failed if that happened. The spare space should be checked before calling compress2, I will make a change. > > + qemu_put_be32(f, blen); > > + f->buf_index += blen; > > + return blen + sizeof(int); > > +} > > + > > +int migrate_qemu_flush(QEMUFile *f_des, QEMUFile *f_src) { > > + int len = 0; > > + > > + if (f_src->buf_index > 0) { > > + len = f_src->buf_index; > > + qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); > > + f_src->buf_index = 0; > > + } > > + return len; > > +} > > Can you explain a bit more here how you're using the src file; I think you're > using it as kind of a dummy buffer; but it needs to be documented > somewhere. Again I'm also not sure of the name of this function. > Yes, it is for dummy buffer use, and I am not satisfied with the function name too.
diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h index 401676b..d70fb8d 100644 --- a/include/migration/qemu-file.h +++ b/include/migration/qemu-file.h @@ -150,6 +150,9 @@ void qemu_put_be32(QEMUFile *f, unsigned int v); void qemu_put_be64(QEMUFile *f, uint64_t v); int qemu_peek_buffer(QEMUFile *f, uint8_t *buf, int size, size_t offset); int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size); +size_t migrate_qemu_add_compression_data(QEMUFile *f, + const uint8_t *p, size_t size, int level); +int migrate_qemu_flush(QEMUFile *f_des, QEMUFile *f_src); /* * Note that you can only peek continuous bytes from where the current pointer * is; you aren't guaranteed to be able to peak to +n bytes unless you've diff --git a/qemu-file.c b/qemu-file.c index f938e36..2668ad0 100644 --- a/qemu-file.c +++ b/qemu-file.c @@ -21,6 +21,7 @@ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ +#include <zlib.h> #include "qemu-common.h" #include "qemu/iov.h" #include "qemu/sockets.h" @@ -993,3 +994,34 @@ QEMUFile *qemu_bufopen(const char *mode, QEMUSizedBuffer *input) } return s->file; } + +/* compress size bytes of data start at p with specific compression + * leve and store the compressed data to the buffer of f. + */ + +size_t migrate_qemu_add_compression_data(QEMUFile *f, + const uint8_t *p, size_t size, int level) +{ + size_t blen = IO_BUF_SIZE - f->buf_index - sizeof(int); + + if (compress2(f->buf + f->buf_index + sizeof(int), &blen, (Bytef *)p, + size, level) != Z_OK) { + error_report("Compress Failed!"); + return 0; + } + qemu_put_be32(f, blen); + f->buf_index += blen; + return blen + sizeof(int); +} + +int migrate_qemu_flush(QEMUFile *f_des, QEMUFile *f_src) +{ + int len = 0; + + if (f_src->buf_index > 0) { + len = f_src->buf_index; + qemu_put_buffer(f_des, f_src->buf, f_src->buf_index); + f_src->buf_index = 0; + } + return len; +}