@@ -156,6 +156,7 @@ typedef struct BDRVRawState {
bool has_write_zeroes:1;
bool discard_zeroes:1;
bool use_linux_aio:1;
+ bool use_linux_io_uring:1;
bool page_cache_inconsistent:1;
bool has_fallocate;
bool needs_alignment;
@@ -425,7 +426,7 @@ static QemuOptsList raw_runtime_opts = {
{
.name = "aio",
.type = QEMU_OPT_STRING,
- .help = "host AIO implementation (threads, native)",
+ .help = "host AIO implementation (threads, native, io_uring)",
},
{
.name = "locking",
@@ -484,9 +485,15 @@ static int raw_open_common(BlockDriverState *bs, QDict *options,
goto fail;
}
- aio_default = (bdrv_flags & BDRV_O_NATIVE_AIO)
- ? BLOCKDEV_AIO_OPTIONS_NATIVE
- : BLOCKDEV_AIO_OPTIONS_THREADS;
+ if (bdrv_flags & BDRV_O_NATIVE_AIO) {
+ aio_default = BLOCKDEV_AIO_OPTIONS_NATIVE;
+#ifdef CONFIG_LINUX_IO_URING
+ } else if (bdrv_flags & BDRV_O_IO_URING) {
+ aio_default = BLOCKDEV_AIO_OPTIONS_IO_URING;
+#endif
+ } else {
+ aio_default = BLOCKDEV_AIO_OPTIONS_THREADS;
+ }
aio = qapi_enum_parse(&BlockdevAioOptions_lookup,
qemu_opt_get(opts, "aio"),
aio_default, &local_err);
@@ -495,7 +502,11 @@ static int raw_open_common(BlockDriverState *bs, QDict *options,
ret = -EINVAL;
goto fail;
}
+
s->use_linux_aio = (aio == BLOCKDEV_AIO_OPTIONS_NATIVE);
+#ifdef CONFIG_LINUX_IO_URING
+ s->use_linux_io_uring = (aio == BLOCKDEV_AIO_OPTIONS_IO_URING);
+#endif
locking = qapi_enum_parse(&OnOffAuto_lookup,
qemu_opt_get(opts, "locking"),
@@ -559,7 +570,7 @@ static int raw_open_common(BlockDriverState *bs, QDict *options,
s->shared_perm = BLK_PERM_ALL;
#ifdef CONFIG_LINUX_AIO
- /* Currently Linux does AIO only for files opened with O_DIRECT */
+ /* Currently Linux does AIO only for files opened with O_DIRECT */
if (s->use_linux_aio) {
if (!(s->open_flags & O_DIRECT)) {
error_setg(errp, "aio=native was specified, but it requires "
@@ -581,6 +592,22 @@ static int raw_open_common(BlockDriverState *bs, QDict *options,
}
#endif /* !defined(CONFIG_LINUX_AIO) */
+#ifdef CONFIG_LINUX_IO_URING
+ if (s->use_linux_io_uring) {
+ if (!aio_setup_linux_io_uring(bdrv_get_aio_context(bs), errp)) {
+ error_prepend(errp, "Unable to use io_uring: ");
+ goto fail;
+ }
+ }
+#else
+ if (s->use_linux_io_uring) {
+ error_setg(errp, "aio=io_uring was specified, but is not supported "
+ "in this build.");
+ ret = -EINVAL;
+ goto fail;
+ }
+#endif /* !defined(CONFIG_LINUX_IO_URING) */
+
s->has_discard = true;
s->has_write_zeroes = true;
if ((bs->open_flags & BDRV_O_NOCACHE) != 0) {
@@ -1874,21 +1901,25 @@ static int coroutine_fn raw_co_prw(BlockDriverState *bs, uint64_t offset,
return -EIO;
/*
- * Check if the underlying device requires requests to be aligned,
- * and if the request we are trying to submit is aligned or not.
- * If this is the case tell the low-level driver that it needs
- * to copy the buffer.
+ * When using O_DIRECT, the request must be aligned to be able to use
+ * either libaio or io_uring interface. If not fail back to regular thread
+ * pool read/write code which emulates this for us if we
+ * set QEMU_AIO_MISALIGNED.
*/
- if (s->needs_alignment) {
- if (!bdrv_qiov_is_aligned(bs, qiov)) {
- type |= QEMU_AIO_MISALIGNED;
+ if (s->needs_alignment && !bdrv_qiov_is_aligned(bs, qiov)) {
+ type |= QEMU_AIO_MISALIGNED;
+#ifdef CONFIG_LINUX_IO_URING
+ } else if (s->use_linux_io_uring) {
+ LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs));
+ assert(qiov->size == bytes);
+ return luring_co_submit(bs, aio, s->fd, offset, qiov, type);
+#endif
#ifdef CONFIG_LINUX_AIO
- } else if (s->use_linux_aio) {
- LinuxAioState *aio = aio_get_linux_aio(bdrv_get_aio_context(bs));
- assert(qiov->size == bytes);
- return laio_co_submit(bs, aio, s->fd, offset, qiov, type);
+ } else if (s->use_linux_aio) {
+ LinuxAioState *aio = aio_get_linux_aio(bdrv_get_aio_context(bs));
+ assert(qiov->size == bytes);
+ return laio_co_submit(bs, aio, s->fd, offset, qiov, type);
#endif
- }
}
acb = (RawPosixAIOData) {
@@ -1924,24 +1955,36 @@ static int coroutine_fn raw_co_pwritev(BlockDriverState *bs, uint64_t offset,
static void raw_aio_plug(BlockDriverState *bs)
{
+ BDRVRawState __attribute__((unused)) *s = bs->opaque;
#ifdef CONFIG_LINUX_AIO
- BDRVRawState *s = bs->opaque;
if (s->use_linux_aio) {
LinuxAioState *aio = aio_get_linux_aio(bdrv_get_aio_context(bs));
laio_io_plug(bs, aio);
}
#endif
+#ifdef CONFIG_LINUX_IO_URING
+ if (s->use_linux_io_uring) {
+ LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs));
+ luring_io_plug(bs, aio);
+ }
+#endif
}
static void raw_aio_unplug(BlockDriverState *bs)
{
+ BDRVRawState __attribute__((unused)) *s = bs->opaque;
#ifdef CONFIG_LINUX_AIO
- BDRVRawState *s = bs->opaque;
if (s->use_linux_aio) {
LinuxAioState *aio = aio_get_linux_aio(bdrv_get_aio_context(bs));
laio_io_unplug(bs, aio);
}
#endif
+#ifdef CONFIG_LINUX_IO_URING
+ if (s->use_linux_io_uring) {
+ LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs));
+ luring_io_unplug(bs, aio);
+ }
+#endif
}
static int raw_co_flush_to_disk(BlockDriverState *bs)
@@ -1961,14 +2004,20 @@ static int raw_co_flush_to_disk(BlockDriverState *bs)
.aio_type = QEMU_AIO_FLUSH,
};
+#ifdef CONFIG_LINUX_IO_URING
+ if (s->use_linux_io_uring) {
+ LuringState *aio = aio_get_linux_io_uring(bdrv_get_aio_context(bs));
+ return luring_co_submit(bs, aio, s->fd, 0, NULL, QEMU_AIO_FLUSH);
+ }
+#endif
return raw_thread_pool_submit(bs, handle_aiocb_flush, &acb);
}
static void raw_aio_attach_aio_context(BlockDriverState *bs,
AioContext *new_context)
{
+ BDRVRawState __attribute__((unused)) *s = bs->opaque;
#ifdef CONFIG_LINUX_AIO
- BDRVRawState *s = bs->opaque;
if (s->use_linux_aio) {
Error *local_err;
if (!aio_setup_linux_aio(new_context, &local_err)) {
@@ -1978,6 +2027,16 @@ static void raw_aio_attach_aio_context(BlockDriverState *bs,
}
}
#endif
+#ifdef CONFIG_LINUX_IO_URING
+ if (s->use_linux_io_uring) {
+ Error *local_err;
+ if (!aio_setup_linux_io_uring(new_context, &local_err)) {
+ error_reportf_err(local_err, "Unable to use linux io_uring, "
+ "falling back to thread pool: ");
+ s->use_linux_io_uring = false;
+ }
+ }
+#endif
}
static void raw_close(BlockDriverState *bs)