Some file-systems, like tmpfs, do not support direct IO, but file-backed namespaces default to using direct IO. If direct IO is unavailable fall back to using buffered IO for the file-backed namespace.
This might not ultimately be a solution for production environments but for test environments it sometimes is feasible to use tmpfs. Signed-off-by: Johannes Thumshirn <[email protected]> --- drivers/nvme/target/io-cmd-file.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c index 517522305e5c..8a861cc0160e 100644 --- a/drivers/nvme/target/io-cmd-file.c +++ b/drivers/nvme/target/io-cmd-file.c @@ -38,11 +38,21 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns) ns->file = filp_open(ns->device_path, flags, 0); if (IS_ERR(ns->file)) { + if (ns->file == ERR_PTR(-EINVAL) && (flags & O_DIRECT)) { + flags &= ~O_DIRECT; + ns->buffered_io = 0; + ns->file = filp_open(ns->device_path, flags, 0); + if (!IS_ERR(ns->file)) { + pr_info("direct I/O unavailable, falling back to buffered I/O\n"); + goto getattr; + } + } pr_err("failed to open file %s: (%ld)\n", ns->device_path, PTR_ERR(ns->file)); return PTR_ERR(ns->file); } +getattr: ret = vfs_getattr(&ns->file->f_path, &stat, STATX_SIZE, AT_STATX_FORCE_SYNC); if (ret) -- 2.16.4
