[PATCH v3 07/15] blockdev: adds bdrv_parse_aio to use io_uring

From: Stefan Hajnoczi <stefanha@redhat.com>
To: <qemu-devel@nongnu.org>
Cc: Fam Zheng <fam@euphon.net>, Kevin Wolf <kwolf@redhat.com>,
	qemu-block@nongnu.org, oleksandr@redhat.com,
	Julia Suvorova <jusual@redhat.com>,
	Markus Armbruster <armbru@redhat.com>,
	Max Reitz <mreitz@redhat.com>,
	Stefan Hajnoczi <stefanha@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Aarushi Mehta <mehta.aaru20@gmail.com>
Subject: [PATCH v3 07/15] blockdev: adds bdrv_parse_aio to use io_uring
Date: Wed, 18 Dec 2019 16:32:20 +0000	[thread overview]
Message-ID: <20191218163228.1613099-8-stefanha@redhat.com> (raw)
In-Reply-To: <20191218163228.1613099-1-stefanha@redhat.com>

From: Aarushi Mehta <mehta.aaru20@gmail.com>

Signed-off-by: Aarushi Mehta <mehta.aaru20@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block.c               | 22 ++++++++++++++++++++++
 blockdev.c            | 12 ++++--------
 include/block/block.h |  1 +
 3 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/block.c b/block.c
index 473eb6eeaa..a06b47c638 100644
--- a/block.c
+++ b/block.c
@@ -845,6 +845,28 @@ static BlockdevDetectZeroesOptions bdrv_parse_detect_zeroes(QemuOpts *opts,
     return detect_zeroes;
 }
 
+/**
+ * Set open flags for aio engine
+ *
+ * Return 0 on success, -1 if the engine specified is invalid
+ */
+int bdrv_parse_aio(const char *mode, int *flags)
+{
+    if (!strcmp(mode, "threads")) {
+        /* do nothing, default */
+    } else if (!strcmp(mode, "native")) {
+        *flags |= BDRV_O_NATIVE_AIO;
+#ifdef CONFIG_LINUX_IO_URING
+    } else if (!strcmp(mode, "io_uring")) {
+        *flags |= BDRV_O_IO_URING;
+#endif
+    } else {
+        return -1;
+    }
+
+    return 0;
+}
+
 /**
  * Set open flags for a given discard mode
  *
diff --git a/blockdev.c b/blockdev.c
index 8e029e9c01..6523f9551d 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -385,13 +385,9 @@ static void extract_common_blockdev_options(QemuOpts *opts, int *bdrv_flags,
         }
 
         if ((aio = qemu_opt_get(opts, "aio")) != NULL) {
-            if (!strcmp(aio, "native")) {
-                *bdrv_flags |= BDRV_O_NATIVE_AIO;
-            } else if (!strcmp(aio, "threads")) {
-                /* this is the default */
-            } else {
-               error_setg(errp, "invalid aio option");
-               return;
+            if (bdrv_parse_aio(aio, bdrv_flags) < 0) {
+                error_setg(errp, "invalid aio option");
+                return;
             }
         }
     }
@@ -4641,7 +4637,7 @@ QemuOptsList qemu_common_drive_opts = {
         },{
             .name = "aio",
             .type = QEMU_OPT_STRING,
-            .help = "host AIO implementation (threads, native)",
+            .help = "host AIO implementation (threads, native, io_uring)",
         },{
             .name = BDRV_OPT_CACHE_WB,
             .type = QEMU_OPT_BOOL,
diff --git a/include/block/block.h b/include/block/block.h
index 7071dc041e..2abe008399 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -300,6 +300,7 @@ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,
 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
                        Error **errp);
 
+int bdrv_parse_aio(const char *mode, int *flags);
 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough);
 int bdrv_parse_discard_flags(const char *mode, int *flags);
 BdrvChild *bdrv_open_child(const char *filename,
-- 
2.23.0


