Re: [PATCH 17/20] migration: remove the QEMUFileOps 'get_buffer' callback
On Thu, Jun 09, 2022 at 05:46:29PM +0100, Dr. David Alan Gilbert wrote:
> * Daniel P. Berrangé (berra...@redhat.com) wrote:
> > This directly implements the get_buffer logic using QIOChannel APIs.
> >
> > Signed-off-by: Daniel P. Berrangé
> > ---
> > migration/qemu-file-channel.c | 29 -
> > migration/qemu-file.c | 18 --
> > migration/qemu-file.h | 9 -
> > 3 files changed, 16 insertions(+), 40 deletions(-)
> >
> > diff --git a/migration/qemu-file-channel.c b/migration/qemu-file-channel.c
> > index 8ff58e81f9..7b32831752 100644
> > --- a/migration/qemu-file-channel.c
> > +++ b/migration/qemu-file-channel.c
> > @@ -74,34 +74,6 @@ static ssize_t channel_writev_buffer(void *opaque,
> > }
> >
> >
> > -static ssize_t channel_get_buffer(void *opaque,
> > - uint8_t *buf,
> > - int64_t pos,
> > - size_t size,
> > - Error **errp)
> > -{
> > -QIOChannel *ioc = QIO_CHANNEL(opaque);
> > -ssize_t ret;
> > -
> > -do {
> > -ret = qio_channel_read(ioc, (char *)buf, size, errp);
> > -if (ret < 0) {
> > -if (ret == QIO_CHANNEL_ERR_BLOCK) {
> > -if (qemu_in_coroutine()) {
> > -qio_channel_yield(ioc, G_IO_IN);
> > -} else {
> > -qio_channel_wait(ioc, G_IO_IN);
> > -}
> > -} else {
> > -return -EIO;
> > -}
> > -}
> > -} while (ret == QIO_CHANNEL_ERR_BLOCK);
> > -
> > -return ret;
> > -}
> > -
> > -
> > static QEMUFile *channel_get_input_return_path(void *opaque)
> > {
> > QIOChannel *ioc = QIO_CHANNEL(opaque);
> > @@ -117,7 +89,6 @@ static QEMUFile *channel_get_output_return_path(void
> > *opaque)
> > }
> >
> > static const QEMUFileOps channel_input_ops = {
> > -.get_buffer = channel_get_buffer,
> > .get_return_path = channel_get_input_return_path,
> > };
> >
> > diff --git a/migration/qemu-file.c b/migration/qemu-file.c
> > index a855ce33dc..e024b43851 100644
> > --- a/migration/qemu-file.c
> > +++ b/migration/qemu-file.c
> > @@ -374,8 +374,22 @@ static ssize_t qemu_fill_buffer(QEMUFile *f)
> > return 0;
> > }
> >
> > -len = f->ops->get_buffer(f->ioc, f->buf + pending,
> > f->total_transferred,
> > - IO_BUF_SIZE - pending, _error);
> > +do {
> > +len = qio_channel_read(f->ioc,
>
> Yes, I think that's OK - not that 'len' is an int where 'ret'
> was a ssize_t; but I think our buffers are guranteed to be 'small'.
There are a few places in qemu-file.c where we're fast & loose
with int rather than size_t, that are probably worth cleaning.
> Reviewed-by: Dr. David Alan Gilbert
With regards,
Daniel
--
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Re: [PATCH 17/20] migration: remove the QEMUFileOps 'get_buffer' callback
* Daniel P. Berrangé (berra...@redhat.com) wrote:
> This directly implements the get_buffer logic using QIOChannel APIs.
>
> Signed-off-by: Daniel P. Berrangé
> ---
> migration/qemu-file-channel.c | 29 -
> migration/qemu-file.c | 18 --
> migration/qemu-file.h | 9 -
> 3 files changed, 16 insertions(+), 40 deletions(-)
>
> diff --git a/migration/qemu-file-channel.c b/migration/qemu-file-channel.c
> index 8ff58e81f9..7b32831752 100644
> --- a/migration/qemu-file-channel.c
> +++ b/migration/qemu-file-channel.c
> @@ -74,34 +74,6 @@ static ssize_t channel_writev_buffer(void *opaque,
> }
>
>
> -static ssize_t channel_get_buffer(void *opaque,
> - uint8_t *buf,
> - int64_t pos,
> - size_t size,
> - Error **errp)
> -{
> -QIOChannel *ioc = QIO_CHANNEL(opaque);
> -ssize_t ret;
> -
> -do {
> -ret = qio_channel_read(ioc, (char *)buf, size, errp);
> -if (ret < 0) {
> -if (ret == QIO_CHANNEL_ERR_BLOCK) {
> -if (qemu_in_coroutine()) {
> -qio_channel_yield(ioc, G_IO_IN);
> -} else {
> -qio_channel_wait(ioc, G_IO_IN);
> -}
> -} else {
> -return -EIO;
> -}
> -}
> -} while (ret == QIO_CHANNEL_ERR_BLOCK);
> -
> -return ret;
> -}
> -
> -
> static QEMUFile *channel_get_input_return_path(void *opaque)
> {
> QIOChannel *ioc = QIO_CHANNEL(opaque);
> @@ -117,7 +89,6 @@ static QEMUFile *channel_get_output_return_path(void
> *opaque)
> }
>
> static const QEMUFileOps channel_input_ops = {
> -.get_buffer = channel_get_buffer,
> .get_return_path = channel_get_input_return_path,
> };
>
> diff --git a/migration/qemu-file.c b/migration/qemu-file.c
> index a855ce33dc..e024b43851 100644
> --- a/migration/qemu-file.c
> +++ b/migration/qemu-file.c
> @@ -374,8 +374,22 @@ static ssize_t qemu_fill_buffer(QEMUFile *f)
> return 0;
> }
>
> -len = f->ops->get_buffer(f->ioc, f->buf + pending, f->total_transferred,
> - IO_BUF_SIZE - pending, _error);
> +do {
> +len = qio_channel_read(f->ioc,
Yes, I think that's OK - not that 'len' is an int where 'ret'
was a ssize_t; but I think our buffers are guranteed to be 'small'.
Reviewed-by: Dr. David Alan Gilbert
> + (char *)f->buf + pending,
> + IO_BUF_SIZE - pending,
> + _error);
> +if (len == QIO_CHANNEL_ERR_BLOCK) {
> +if (qemu_in_coroutine()) {
> +qio_channel_yield(f->ioc, G_IO_IN);
> +} else {
> +qio_channel_wait(f->ioc, G_IO_IN);
> +}
> +} else if (len < 0) {
> +len = EIO;
> +}
> +} while (len == QIO_CHANNEL_ERR_BLOCK);
> +
> if (len > 0) {
> f->buf_size += len;
> f->total_transferred += len;
> diff --git a/migration/qemu-file.h b/migration/qemu-file.h
> index 7ec105bf96..cd49184c00 100644
> --- a/migration/qemu-file.h
> +++ b/migration/qemu-file.h
> @@ -29,14 +29,6 @@
> #include "exec/cpu-common.h"
> #include "io/channel.h"
>
> -/* 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 ssize_t (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
> -int64_t pos, size_t size,
> -Error **errp);
> -
> /*
> * This function writes an iovec to file. The handler must write all
> * of the data or return a negative errno value.
> @@ -77,7 +69,6 @@ typedef size_t (QEMURamSaveFunc)(QEMUFile *f,
> typedef QEMUFile *(QEMURetPathFunc)(void *opaque);
>
> typedef struct QEMUFileOps {
> -QEMUFileGetBufferFunc *get_buffer;
> QEMUFileWritevBufferFunc *writev_buffer;
> QEMURetPathFunc *get_return_path;
> } QEMUFileOps;
> --
> 2.36.1
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
[PATCH 17/20] migration: remove the QEMUFileOps 'get_buffer' callback
This directly implements the get_buffer logic using QIOChannel APIs.
Signed-off-by: Daniel P. Berrangé
---
migration/qemu-file-channel.c | 29 -
migration/qemu-file.c | 18 --
migration/qemu-file.h | 9 -
3 files changed, 16 insertions(+), 40 deletions(-)
diff --git a/migration/qemu-file-channel.c b/migration/qemu-file-channel.c
index 8ff58e81f9..7b32831752 100644
--- a/migration/qemu-file-channel.c
+++ b/migration/qemu-file-channel.c
@@ -74,34 +74,6 @@ static ssize_t channel_writev_buffer(void *opaque,
}
-static ssize_t channel_get_buffer(void *opaque,
- uint8_t *buf,
- int64_t pos,
- size_t size,
- Error **errp)
-{
-QIOChannel *ioc = QIO_CHANNEL(opaque);
-ssize_t ret;
-
-do {
-ret = qio_channel_read(ioc, (char *)buf, size, errp);
-if (ret < 0) {
-if (ret == QIO_CHANNEL_ERR_BLOCK) {
-if (qemu_in_coroutine()) {
-qio_channel_yield(ioc, G_IO_IN);
-} else {
-qio_channel_wait(ioc, G_IO_IN);
-}
-} else {
-return -EIO;
-}
-}
-} while (ret == QIO_CHANNEL_ERR_BLOCK);
-
-return ret;
-}
-
-
static QEMUFile *channel_get_input_return_path(void *opaque)
{
QIOChannel *ioc = QIO_CHANNEL(opaque);
@@ -117,7 +89,6 @@ static QEMUFile *channel_get_output_return_path(void *opaque)
}
static const QEMUFileOps channel_input_ops = {
-.get_buffer = channel_get_buffer,
.get_return_path = channel_get_input_return_path,
};
diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index a855ce33dc..e024b43851 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -374,8 +374,22 @@ static ssize_t qemu_fill_buffer(QEMUFile *f)
return 0;
}
-len = f->ops->get_buffer(f->ioc, f->buf + pending, f->total_transferred,
- IO_BUF_SIZE - pending, _error);
+do {
+len = qio_channel_read(f->ioc,
+ (char *)f->buf + pending,
+ IO_BUF_SIZE - pending,
+ _error);
+if (len == QIO_CHANNEL_ERR_BLOCK) {
+if (qemu_in_coroutine()) {
+qio_channel_yield(f->ioc, G_IO_IN);
+} else {
+qio_channel_wait(f->ioc, G_IO_IN);
+}
+} else if (len < 0) {
+len = EIO;
+}
+} while (len == QIO_CHANNEL_ERR_BLOCK);
+
if (len > 0) {
f->buf_size += len;
f->total_transferred += len;
diff --git a/migration/qemu-file.h b/migration/qemu-file.h
index 7ec105bf96..cd49184c00 100644
--- a/migration/qemu-file.h
+++ b/migration/qemu-file.h
@@ -29,14 +29,6 @@
#include "exec/cpu-common.h"
#include "io/channel.h"
-/* 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 ssize_t (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
-int64_t pos, size_t size,
-Error **errp);
-
/*
* This function writes an iovec to file. The handler must write all
* of the data or return a negative errno value.
@@ -77,7 +69,6 @@ typedef size_t (QEMURamSaveFunc)(QEMUFile *f,
typedef QEMUFile *(QEMURetPathFunc)(void *opaque);
typedef struct QEMUFileOps {
-QEMUFileGetBufferFunc *get_buffer;
QEMUFileWritevBufferFunc *writev_buffer;
QEMURetPathFunc *get_return_path;
} QEMUFileOps;
--
2.36.1
