* Yury Kotov (yury-ko...@yandex-team.ru) wrote:
> Hi, I'm a bit worried that this patch might have been forgotten.
> Is it queued? Thanks!
I've added it to my list for the pull I'll do as soon as 4.2 opens.
Dave
> 14.06.2019, 19:56, "Dr. David Alan Gilbert" <dgilb...@redhat.com>:
> > * Yury Kotov (yury-ko...@yandex-team.ru) wrote:
> >> Currently, there is no information about error if outgoing migration was
> >> failed
> >> because of file channel errors.
> >> Example (QMP session):
> >> -> { "execute": "migrate", "arguments": { "uri": "exec:head -c 1" }}
> >> <- { "return": {} }
> >> ...
> >> -> { "execute": "query-migrate" }
> >> <- { "return": { "status": "failed" }} // There is not error's description
> >>
> >> And even in the QEMU's output there is nothing.
> >>
> >> This patch
> >> 1) Adds errp for the most of QEMUFileOps
> >> 2) Adds qemu_file_get_error_obj/qemu_file_set_error_obj
> >> 3) And finally using of qemu_file_get_error_obj in migration.c
> >>
> >> And now, the status for the mentioned fail will be:
> >> -> { "execute": "query-migrate" }
> >> <- { "return": { "status": "failed",
> >> "error-desc": "Unable to write to command: Broken pipe"
> >> }}
> >>
> >> Signed-off-by: Yury Kotov <yury-ko...@yandex-team.ru>
> >
> > Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> >
> >> ---
> >> migration/migration.c | 10 ++++--
> >> migration/qemu-file-channel.c | 30 +++++++++--------
> >> migration/qemu-file.c | 63 ++++++++++++++++++++++++++++-------
> >> migration/qemu-file.h | 15 ++++++---
> >> migration/savevm.c | 6 ++--
> >> 5 files changed, 88 insertions(+), 36 deletions(-)
> >>
> >> diff --git a/migration/migration.c b/migration/migration.c
> >> index 609e0df5d0..7bcdc4613b 100644
> >> --- a/migration/migration.c
> >> +++ b/migration/migration.c
> >> @@ -2949,6 +2949,7 @@ static MigThrError
> >> migration_detect_error(MigrationState *s)
> >> {
> >> int ret;
> >> int state = s->state;
> >> + Error *local_error = NULL;
> >>
> >> if (state == MIGRATION_STATUS_CANCELLING ||
> >> state == MIGRATION_STATUS_CANCELLED) {
> >> @@ -2957,13 +2958,18 @@ static MigThrError
> >> migration_detect_error(MigrationState *s)
> >> }
> >>
> >> /* Try to detect any file errors */
> >> - ret = qemu_file_get_error(s->to_dst_file);
> >> -
> >> + ret = qemu_file_get_error_obj(s->to_dst_file, &local_error);
> >> if (!ret) {
> >> /* Everything is fine */
> >> + assert(!local_error);
> >> return MIG_THR_ERR_NONE;
> >> }
> >>
> >> + if (local_error) {
> >> + migrate_set_error(s, local_error);
> >> + error_free(local_error);
> >> + }
> >> +
> >> if (state == MIGRATION_STATUS_POSTCOPY_ACTIVE && ret == -EIO) {
> >> /*
> >> * For postcopy, we allow the network to be down for a
> >> diff --git a/migration/qemu-file-channel.c b/migration/qemu-file-channel.c
> >> index 8e639eb496..c382ea2d78 100644
> >> --- a/migration/qemu-file-channel.c
> >> +++ b/migration/qemu-file-channel.c
> >> @@ -33,7 +33,8 @@
> >> static ssize_t channel_writev_buffer(void *opaque,
> >> struct iovec *iov,
> >> int iovcnt,
> >> - int64_t pos)
> >> + int64_t pos,
> >> + Error **errp)
> >> {
> >> QIOChannel *ioc = QIO_CHANNEL(opaque);
> >> ssize_t done = 0;
> >> @@ -47,7 +48,7 @@ static ssize_t channel_writev_buffer(void *opaque,
> >>
> >> while (nlocal_iov > 0) {
> >> ssize_t len;
> >> - len = qio_channel_writev(ioc, local_iov, nlocal_iov, NULL);
> >> + len = qio_channel_writev(ioc, local_iov, nlocal_iov, errp);
> >> if (len == QIO_CHANNEL_ERR_BLOCK) {
> >> if (qemu_in_coroutine()) {
> >> qio_channel_yield(ioc, G_IO_OUT);
> >> @@ -57,7 +58,6 @@ static ssize_t channel_writev_buffer(void *opaque,
> >> continue;
> >> }
> >> if (len < 0) {
> >> - /* XXX handle Error objects */
> >> done = -EIO;
> >> goto cleanup;
> >> }
> >> @@ -75,13 +75,14 @@ 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)
> >> + size_t size,
> >> + Error **errp)
> >> {
> >> QIOChannel *ioc = QIO_CHANNEL(opaque);
> >> ssize_t ret;
> >>
> >> do {
> >> - ret = qio_channel_read(ioc, (char *)buf, size, NULL);
> >> + ret = qio_channel_read(ioc, (char *)buf, size, errp);
> >> if (ret < 0) {
> >> if (ret == QIO_CHANNEL_ERR_BLOCK) {
> >> if (qemu_in_coroutine()) {
> >> @@ -90,7 +91,6 @@ static ssize_t channel_get_buffer(void *opaque,
> >> qio_channel_wait(ioc, G_IO_IN);
> >> }
> >> } else {
> >> - /* XXX handle Error * object */
> >> return -EIO;
> >> }
> >> }
> >> @@ -100,18 +100,20 @@ static ssize_t channel_get_buffer(void *opaque,
> >> }
> >>
> >> -static int channel_close(void *opaque)
> >> +static int channel_close(void *opaque, Error **errp)
> >> {
> >> + int ret;
> >> QIOChannel *ioc = QIO_CHANNEL(opaque);
> >> - qio_channel_close(ioc, NULL);
> >> + ret = qio_channel_close(ioc, errp);
> >> object_unref(OBJECT(ioc));
> >> - return 0;
> >> + return ret;
> >> }
> >>
> >> static int channel_shutdown(void *opaque,
> >> bool rd,
> >> - bool wr)
> >> + bool wr,
> >> + Error **errp)
> >> {
> >> QIOChannel *ioc = QIO_CHANNEL(opaque);
> >>
> >> @@ -125,8 +127,7 @@ static int channel_shutdown(void *opaque,
> >> } else {
> >> mode = QIO_CHANNEL_SHUTDOWN_WRITE;
> >> }
> >> - if (qio_channel_shutdown(ioc, mode, NULL) < 0) {
> >> - /* XXX handler Error * object */
> >> + if (qio_channel_shutdown(ioc, mode, errp) < 0) {
> >> return -EIO;
> >> }
> >> }
> >> @@ -135,11 +136,12 @@ static int channel_shutdown(void *opaque,
> >>
> >> static int channel_set_blocking(void *opaque,
> >> - bool enabled)
> >> + bool enabled,
> >> + Error **errp)
> >> {
> >> QIOChannel *ioc = QIO_CHANNEL(opaque);
> >>
> >> - if (qio_channel_set_blocking(ioc, enabled, NULL) < 0) {
> >> + if (qio_channel_set_blocking(ioc, enabled, errp) < 0) {
> >> return -1;
> >> }
> >> return 0;
> >> diff --git a/migration/qemu-file.c b/migration/qemu-file.c
> >> index 977b9ae07c..c52160e08b 100644
> >> --- a/migration/qemu-file.c
> >> +++ b/migration/qemu-file.c
> >> @@ -29,6 +29,7 @@
> >> #include "migration.h"
> >> #include "qemu-file.h"
> >> #include "trace.h"
> >> +#include "qapi/error.h"
> >>
> >> #define IO_BUF_SIZE 32768
> >> #define MAX_IOV_SIZE MIN(IOV_MAX, 64)
> >> @@ -52,6 +53,7 @@ struct QEMUFile {
> >> unsigned int iovcnt;
> >>
> >> int last_error;
> >> + Error *last_error_obj;
> >> };
> >>
> >> /*
> >> @@ -63,7 +65,7 @@ int qemu_file_shutdown(QEMUFile *f)
> >> if (!f->ops->shut_down) {
> >> return -ENOSYS;
> >> }
> >> - return f->ops->shut_down(f->opaque, true, true);
> >> + return f->ops->shut_down(f->opaque, true, true, NULL);
> >> }
> >>
> >> /*
> >> @@ -108,24 +110,55 @@ void qemu_file_set_hooks(QEMUFile *f, const
> >> QEMUFileHooks *hooks)
> >> }
> >>
> >> /*
> >> - * Get last error for stream f
> >> + * Get last error for stream f with optional Error*
> >> *
> >> * Return negative error value if there has been an error on previous
> >> * operations, return 0 if no error happened.
> >> + * Optional, it returns Error* in errp, but it may be NULL even if
> >> return value
> >> + * is not 0.
> >> *
> >> */
> >> -int qemu_file_get_error(QEMUFile *f)
> >> +int qemu_file_get_error_obj(QEMUFile *f, Error **errp)
> >> {
> >> + if (errp) {
> >> + *errp = f->last_error_obj ? error_copy(f->last_error_obj) : NULL;
> >> + }
> >> return f->last_error;
> >> }
> >>
> >> -void qemu_file_set_error(QEMUFile *f, int ret)
> >> +/*
> >> + * Set the last error for stream f with optional Error*
> >> + */
> >> +void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err)
> >> {
> >> - if (f->last_error == 0) {
> >> + if (f->last_error == 0 && ret) {
> >> f->last_error = ret;
> >> + error_propagate(&f->last_error_obj, err);
> >> + } else if (err) {
> >> + error_report_err(err);
> >> }
> >> }
> >>
> >> +/*
> >> + * Get last error for stream f
> >> + *
> >> + * Return negative error value if there has been an error on previous
> >> + * operations, return 0 if no error happened.
> >> + *
> >> + */
> >> +int qemu_file_get_error(QEMUFile *f)
> >> +{
> >> + return qemu_file_get_error_obj(f, NULL);
> >> +}
> >> +
> >> +/*
> >> + * Set the last error for stream f
> >> + */
> >> +void qemu_file_set_error(QEMUFile *f, int ret)
> >> +{
> >> + qemu_file_set_error_obj(f, ret, NULL);
> >> +}
> >> +
> >> bool qemu_file_is_writable(QEMUFile *f)
> >> {
> >> return f->ops->writev_buffer;
> >> @@ -177,6 +210,7 @@ void qemu_fflush(QEMUFile *f)
> >> {
> >> ssize_t ret = 0;
> >> ssize_t expect = 0;
> >> + Error *local_error = NULL;
> >>
> >> if (!qemu_file_is_writable(f)) {
> >> return;
> >> @@ -184,7 +218,8 @@ void qemu_fflush(QEMUFile *f)
> >>
> >> if (f->iovcnt > 0) {
> >> expect = iov_size(f->iov, f->iovcnt);
> >> - ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos);
> >> + ret = f->ops->writev_buffer(f->opaque, f->iov, f->iovcnt, f->pos,
> >> + &local_error);
> >>
> >> qemu_iovec_release_ram(f);
> >> }
> >> @@ -196,7 +231,7 @@ void qemu_fflush(QEMUFile *f)
> >> * data set we requested, so sanity check that.
> >> */
> >> if (ret != expect) {
> >> - qemu_file_set_error(f, ret < 0 ? ret : -EIO);
> >> + qemu_file_set_error_obj(f, ret < 0 ? ret : -EIO, local_error);
> >> }
> >> f->buf_index = 0;
> >> f->iovcnt = 0;
> >> @@ -284,6 +319,7 @@ static ssize_t qemu_fill_buffer(QEMUFile *f)
> >> {
> >> int len;
> >> int pending;
> >> + Error *local_error = NULL;
> >>
> >> assert(!qemu_file_is_writable(f));
> >>
> >> @@ -295,14 +331,16 @@ static ssize_t qemu_fill_buffer(QEMUFile *f)
> >> f->buf_size = pending;
> >>
> >> len = f->ops->get_buffer(f->opaque, f->buf + pending, f->pos,
> >> - IO_BUF_SIZE - pending);
> >> + IO_BUF_SIZE - pending, &local_error);
> >> if (len > 0) {
> >> f->buf_size += len;
> >> f->pos += len;
> >> } else if (len == 0) {
> >> - qemu_file_set_error(f, -EIO);
> >> + qemu_file_set_error_obj(f, -EIO, local_error);
> >> } else if (len != -EAGAIN) {
> >> - qemu_file_set_error(f, len);
> >> + qemu_file_set_error_obj(f, len, local_error);
> >> + } else {
> >> + error_free(local_error);
> >> }
> >>
> >> return len;
> >> @@ -328,7 +366,7 @@ int qemu_fclose(QEMUFile *f)
> >> ret = qemu_file_get_error(f);
> >>
> >> if (f->ops->close) {
> >> - int ret2 = f->ops->close(f->opaque);
> >> + int ret2 = f->ops->close(f->opaque, NULL);
> >> if (ret >= 0) {
> >> ret = ret2;
> >> }
> >> @@ -339,6 +377,7 @@ int qemu_fclose(QEMUFile *f)
> >> if (f->last_error) {
> >> ret = f->last_error;
> >> }
> >> + error_free(f->last_error_obj);
> >> g_free(f);
> >> trace_qemu_file_fclose();
> >> return ret;
> >> @@ -784,6 +823,6 @@ void qemu_put_counted_string(QEMUFile *f, const char
> >> *str)
> >> void qemu_file_set_blocking(QEMUFile *f, bool block)
> >> {
> >> if (f->ops->set_blocking) {
> >> - f->ops->set_blocking(f->opaque, block);
> >> + f->ops->set_blocking(f->opaque, block, NULL);
> >> }
> >> }
> >> diff --git a/migration/qemu-file.h b/migration/qemu-file.h
> >> index 13baf896bd..eb886db65f 100644
> >> --- a/migration/qemu-file.h
> >> +++ b/migration/qemu-file.h
> >> @@ -32,7 +32,8 @@
> >> * bytes actually read should be returned.
> >> */
> >> typedef ssize_t (QEMUFileGetBufferFunc)(void *opaque, uint8_t *buf,
> >> - int64_t pos, size_t size);
> >> + int64_t pos, size_t size,
> >> + Error **errp);
> >>
> >> /* Close a file
> >> *
> >> @@ -41,7 +42,7 @@ typedef ssize_t (QEMUFileGetBufferFunc)(void *opaque,
> >> uint8_t *buf,
> >> * The meaning of return value on success depends on the specific
> >> back-end being
> >> * used.
> >> */
> >> -typedef int (QEMUFileCloseFunc)(void *opaque);
> >> +typedef int (QEMUFileCloseFunc)(void *opaque, Error **errp);
> >>
> >> /* Called to return the OS file descriptor associated to the QEMUFile.
> >> */
> >> @@ -49,14 +50,15 @@ typedef int (QEMUFileGetFD)(void *opaque);
> >>
> >> /* Called to change the blocking mode of the file
> >> */
> >> -typedef int (QEMUFileSetBlocking)(void *opaque, bool enabled);
> >> +typedef int (QEMUFileSetBlocking)(void *opaque, bool enabled, Error
> >> **errp);
> >>
> >> /*
> >> * 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);
> >> + int iovcnt, int64_t pos,
> >> + Error **errp);
> >>
> >> /*
> >> * This function provides hooks around different
> >> @@ -97,7 +99,8 @@ typedef QEMUFile *(QEMURetPathFunc)(void *opaque);
> >> * Existing blocking reads/writes must be woken
> >> * Returns 0 on success, -err on error
> >> */
> >> -typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr);
> >> +typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr,
> >> + Error **errp);
> >>
> >> typedef struct QEMUFileOps {
> >> QEMUFileGetBufferFunc *get_buffer;
> >> @@ -149,6 +152,8 @@ void qemu_update_position(QEMUFile *f, size_t size);
> >> void qemu_file_reset_rate_limit(QEMUFile *f);
> >> void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate);
> >> int64_t qemu_file_get_rate_limit(QEMUFile *f);
> >> +int qemu_file_get_error_obj(QEMUFile *f, Error **errp);
> >> +void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err);
> >> void qemu_file_set_error(QEMUFile *f, int ret);
> >> int qemu_file_shutdown(QEMUFile *f);
> >> QEMUFile *qemu_file_get_return_path(QEMUFile *f);
> >> diff --git a/migration/savevm.c b/migration/savevm.c
> >> index 34bcad3807..a619af744d 100644
> >> --- a/migration/savevm.c
> >> +++ b/migration/savevm.c
> >> @@ -124,7 +124,7 @@ static struct mig_cmd_args {
> >> /* savevm/loadvm support */
> >>
> >> static ssize_t block_writev_buffer(void *opaque, struct iovec *iov, int
> >> iovcnt,
> >> - int64_t pos)
> >> + int64_t pos, Error **errp)
> >> {
> >> int ret;
> >> QEMUIOVector qiov;
> >> @@ -139,12 +139,12 @@ static ssize_t block_writev_buffer(void *opaque,
> >> struct iovec *iov, int iovcnt,
> >> }
> >>
> >> static ssize_t block_get_buffer(void *opaque, uint8_t *buf, int64_t pos,
> >> - size_t size)
> >> + size_t size, Error **errp)
> >> {
> >> return bdrv_load_vmstate(opaque, buf, pos, size);
> >> }
> >>
> >> -static int bdrv_fclose(void *opaque)
> >> +static int bdrv_fclose(void *opaque, Error **errp)
> >> {
> >> return bdrv_flush(opaque);
> >> }
> >> --
> >> 2.21.0
> > --
> > Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
>
> Regards,
> Yury
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
