From 294682cc3a7c5b3d1b2d45b686e2d8523750ce64 Mon Sep 17 00:00:00 2001 From: Andrey Shinkevich Date: Tue, 27 Aug 2019 16:52:53 +0300 Subject: [PATCH] block: workaround for unaligned byte range in fallocate() Revert the commit 118f99442d 'block/io.c: fix for the allocation failure' and use better error handling for file systems that do not support fallocate() for an unaligned byte range. Allow falling back to pwrite in case fallocate() returns EINVAL. Suggested-by: Kevin Wolf Suggested-by: Eric Blake Signed-off-by: Andrey Shinkevich Reviewed-by: Eric Blake Reviewed-by: Denis V. Lunev Message-Id: <1566913973-15490-1-git-send-email-andrey.shinkevich@virtuozzo.com> Signed-off-by: Eric Blake --- block/file-posix.c | 7 +++++++ block/io.c | 2 +- 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/block/file-posix.c b/block/file-posix.c index 71f168ee2f..87c5a4ccbd 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1588,6 +1588,13 @@ static int handle_aiocb_write_zeroes(void *opaque) if (s->has_write_zeroes) { int ret = do_fallocate(s->fd, FALLOC_FL_ZERO_RANGE, aiocb->aio_offset, aiocb->aio_nbytes); + if (ret == -EINVAL) { + /* + * Allow falling back to pwrite for file systems that + * do not support fallocate() for an unaligned byte range. + */ + return -ENOTSUP; + } if (ret == 0 || ret != -ENOTSUP) { return ret; } diff --git a/block/io.c b/block/io.c index 0fa10831ed..16a598fd08 100644 --- a/block/io.c +++ b/block/io.c @@ -1746,7 +1746,7 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, assert(!bs->supported_zero_flags); } - if (ret < 0 && !(flags & BDRV_REQ_NO_FALLBACK)) { + if (ret == -ENOTSUP && !(flags & BDRV_REQ_NO_FALLBACK)) { /* Fall back to bounce buffer if write zeroes is unsupported */ BdrvRequestFlags write_flags = flags & ~BDRV_REQ_ZERO_WRITE; -- 2.30.2