From c8807c5edcc8bd8917a5b7531d47ef6a99e07bd8 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Thu, 10 Dec 2020 13:52:02 +0100 Subject: [PATCH] block/nvme: Implement fake truncate() coroutine MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit NVMe drive cannot be shrunk. Since commit c80d8b06cfa we can use the @exact parameter (set to false) to return success if the block device is larger than the requested offset (even if we can not be shrunk). Use this parameter to implement the NVMe truncate() coroutine, similarly how it is done for the iscsi and file-posix drivers (see commit 82325ae5f2f "Evaluate @exact in protocol drivers"). Reported-by: Xueqiang Wei Suggested-by: Max Reitz Signed-off-by: Philippe Mathieu-Daudé Message-Id: <20201210125202.858656-1-philmd@redhat.com> Signed-off-by: Max Reitz --- block/nvme.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/block/nvme.c b/block/nvme.c index a06a188d53..5a6fbacf4a 100644 --- a/block/nvme.c +++ b/block/nvme.c @@ -1389,6 +1389,29 @@ out: } +static int coroutine_fn nvme_co_truncate(BlockDriverState *bs, int64_t offset, + bool exact, PreallocMode prealloc, + BdrvRequestFlags flags, Error **errp) +{ + int64_t cur_length; + + if (prealloc != PREALLOC_MODE_OFF) { + error_setg(errp, "Unsupported preallocation mode '%s'", + PreallocMode_str(prealloc)); + return -ENOTSUP; + } + + cur_length = nvme_getlength(bs); + if (offset != cur_length && exact) { + error_setg(errp, "Cannot resize NVMe devices"); + return -ENOTSUP; + } else if (offset > cur_length) { + error_setg(errp, "Cannot grow NVMe devices"); + return -EINVAL; + } + + return 0; +} static int nvme_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, Error **errp) @@ -1523,6 +1546,7 @@ static BlockDriver bdrv_nvme = { .bdrv_close = nvme_close, .bdrv_getlength = nvme_getlength, .bdrv_probe_blocksizes = nvme_probe_blocksizes, + .bdrv_co_truncate = nvme_co_truncate, .bdrv_co_preadv = nvme_co_preadv, .bdrv_co_pwritev = nvme_co_pwritev, -- 2.11.0