From 60cb2fa7eb5431d8996589ebc5dde865c602d54b Mon Sep 17 00:00:00 2001 From: Eric Blake 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 Signed-off-by: Kevin Wolf --- 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 f8f88a6d5f4..6ac76d01764 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 , @@ -998,6 +998,14 @@ 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) @@ -1011,6 +1019,14 @@ 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 851376b5b0d..73df1a677c4 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 , @@ -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, -- 2.39.5