These will behave more like normal files in that writes beyond the EOF will automatically grow the export size.
Signed-off-by: Max Reitz <[email protected]> --- block/fuse.c | 16 +++++++++++++++- qapi/block.json | 6 +++++- 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/block/fuse.c b/block/fuse.c index 4e662e6dfb..d7c7824815 100644 --- a/block/fuse.c +++ b/block/fuse.c @@ -42,6 +42,7 @@ typedef struct BdrvFuseSession { uint64_t perm, shared_perm; bool mounted, fd_handler_set_up; bool writable; + bool growable; } BdrvFuseSession; static GHashTable *sessions; @@ -59,6 +60,7 @@ static bool is_regular_file(const char *path, Error **errp); void qmp_fuse_export_add(const char *node_name, const char *mountpoint, bool has_writable, bool writable, + bool has_growable, bool growable, Error **errp) { BlockDriverState *bs; @@ -67,6 +69,9 @@ void qmp_fuse_export_add(const char *node_name, const char *mountpoint, if (!has_writable) { writable = false; } + if (!has_growable) { + growable = false; + } init_fuse(); @@ -98,6 +103,7 @@ void qmp_fuse_export_add(const char *node_name, const char *mountpoint, }, .writable = writable, + .growable = growable, }; session->perm = BLK_PERM_CONSISTENT_READ; @@ -463,7 +469,15 @@ static void fuse_write(fuse_req_t req, fuse_ino_t inode, const char *buf, size = MIN(size, BDRV_REQUEST_MAX_BYTES); if (offset + size > length) { - size = length - offset; + if (session->growable) { + ret = fuse_do_truncate(session, offset + size, PREALLOC_MODE_OFF); + if (ret < 0) { + fuse_reply_err(req, -ret); + return; + } + } else { + size = length - offset; + } } ret = blk_pwrite(session->blk, offset, buf, size, 0); diff --git a/qapi/block.json b/qapi/block.json index 26768dc8ef..039cbc6773 100644 --- a/qapi/block.json +++ b/qapi/block.json @@ -330,13 +330,17 @@ # @writable: Whether clients should be able to write to the block # device via the FUSE export. (default: false) # +# @growable: Whether writes beyond the EOF should grow the block node +# fit. (default: false) +# # Since: 5.0 ## { 'command': 'fuse-export-add', 'data': { 'node-name': 'str', 'mountpoint': 'str', - '*writable': 'bool' + '*writable': 'bool', + '*growable': 'bool' }, 'if': 'defined(CONFIG_FUSE)' } -- 2.23.0
