File 0225-block-Introduce-byte-based-aio-read.patch of Package qemu.5923
From 02896a8e1d83461fe1cc475ac0eaf68ceab77be4 Mon Sep 17 00:00:00 2001
From: Eric Blake <eblake@redhat.com>
Date: Fri, 6 May 2016 10:26:30 -0600
Subject: [PATCH] block: Introduce byte-based aio read/write
blk_aio_readv() and blk_aio_writev() are annoying in that they
can't access sub-sector granularity, and cannot pass flags.
Also, they require the caller to pass redundant information
about the size of the I/O (qiov->size in bytes must match
nb_sectors in sectors).
Add new blk_aio_preadv() and blk_aio_pwritev() functions to fix
the flaws. The next few patches will upgrade callers, then
finally delete the old interfaces.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 60cb2fa7eb5431d8996589ebc5dde865c602d54b)
[LM: BSC#1043176]
Signed-off-by: Lin Ma <lma@suse.com>
---
block/block-backend.c | 18 +++++++++++++++++-
include/sysemu/block-backend.h | 8 +++++++-
2 files changed, 24 insertions(+), 2 deletions(-)
diff --git a/block/block-backend.c b/block/block-backend.c
index 82e70b9377..de71d75c3d 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -1,7 +1,7 @@
/*
* QEMU Block backends
*
- * Copyright (C) 2014 Red Hat, Inc.
+ * Copyright (C) 2014-2016 Red Hat, Inc.
*
* Authors:
* Markus Armbruster <armbru@redhat.com>,
@@ -1000,6 +1000,14 @@ BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num,
blk_aio_read_entry, 0, cb, opaque);
}
+BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset,
+ QEMUIOVector *qiov, BdrvRequestFlags flags,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ return blk_aio_prwv(blk, offset, qiov->size, qiov,
+ blk_aio_read_entry, flags, cb, opaque);
+}
+
BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num,
QEMUIOVector *iov, int nb_sectors,
BlockCompletionFunc *cb, void *opaque)
@@ -1013,6 +1021,14 @@ BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num,
blk_aio_write_entry, 0, cb, opaque);
}
+BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset,
+ QEMUIOVector *qiov, BdrvRequestFlags flags,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ return blk_aio_prwv(blk, offset, qiov->size, qiov,
+ blk_aio_write_entry, flags, cb, opaque);
+}
+
BlockAIOCB *blk_aio_flush(BlockBackend *blk,
BlockCompletionFunc *cb, void *opaque)
{
diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h
index c3f7d902b8..745f0ef3d9 100644
--- a/include/sysemu/block-backend.h
+++ b/include/sysemu/block-backend.h
@@ -1,7 +1,7 @@
/*
* QEMU Block backends
*
- * Copyright (C) 2014 Red Hat, Inc.
+ * Copyright (C) 2014-2016 Red Hat, Inc.
*
* Authors:
* Markus Armbruster <armbru@redhat.com>,
@@ -110,9 +110,15 @@ int64_t blk_nb_sectors(BlockBackend *blk);
BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num,
QEMUIOVector *iov, int nb_sectors,
BlockCompletionFunc *cb, void *opaque);
+BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset,
+ QEMUIOVector *qiov, BdrvRequestFlags flags,
+ BlockCompletionFunc *cb, void *opaque);
BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num,
QEMUIOVector *iov, int nb_sectors,
BlockCompletionFunc *cb, void *opaque);
+BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset,
+ QEMUIOVector *qiov, BdrvRequestFlags flags,
+ BlockCompletionFunc *cb, void *opaque);
BlockAIOCB *blk_aio_flush(BlockBackend *blk,
BlockCompletionFunc *cb, void *opaque);
BlockAIOCB *blk_aio_discard(BlockBackend *blk,
