[PATCH 13/14] libfuse: add upper level iomap_config implementation

["Darrick J. Wong" <djwong@xxxxxxxxxx>]

From: Darrick J. Wong <djwong@xxxxxxxxxx>

Add FUSE_IOMAP_CONFIG helpers to the upper level fuse library.

Signed-off-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
---
 include/fuse.h |    7 +++++++
 lib/fuse.c     |   37 +++++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)


diff --git a/include/fuse.h b/include/fuse.h
index f894dd5da0d106..6ce6ccfd102386 100644
--- a/include/fuse.h
+++ b/include/fuse.h
@@ -883,6 +883,13 @@ struct fuse_operations {
 	 */
 	int (*getattr_iflags) (const char *path, struct stat *buf,
 			       unsigned int *iflags, struct fuse_file_info *fi);
+
+	/**
+	 * Configure the filesystem geometry that will be used by iomap
+	 * files.
+	 */
+	int (*iomap_config) (uint32_t flags, off_t maxbytes,
+			     struct fuse_iomap_config *cfg);
 #endif /* FUSE_USE_VERSION >= 318 */
 };
 
diff --git a/lib/fuse.c b/lib/fuse.c
index 685d0181e569d0..b722a1b526e3de 100644
--- a/lib/fuse.c
+++ b/lib/fuse.c
@@ -2870,6 +2870,23 @@ static int fuse_fs_iomap_ioend(struct fuse_fs *fs, const char *path,
 				  ioendflags, error, new_addr);
 }
 
+static int fuse_fs_iomap_config(struct fuse_fs *fs, uint32_t flags,
+				int64_t maxbytes,
+				struct fuse_iomap_config *cfg)
+{
+	fuse_get_context()->private_data = fs->user_data;
+	if (!fs->op.iomap_config)
+		return -ENOSYS;
+
+	if (fs->debug) {
+		fuse_log(FUSE_LOG_DEBUG,
+			 "iomap_config flags 0x%x maxbytes %lld\n",
+			 flags, (long long)maxbytes);
+	}
+
+	return fs->op.iomap_config(flags, maxbytes, cfg);
+}
+
 static void fuse_lib_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr,
 			     int valid, struct fuse_file_info *fi)
 {
@@ -4637,6 +4654,25 @@ static void fuse_lib_iomap_ioend(fuse_req_t req, fuse_ino_t nodeid,
 	reply_err(req, err);
 }
 
+static void fuse_lib_iomap_config(fuse_req_t req, uint32_t flags,
+				  int64_t maxbytes)
+{
+	struct fuse_iomap_config cfg = { };
+	struct fuse *f = req_fuse_prepare(req);
+	struct fuse_intr_data d;
+	int err;
+
+	fuse_prepare_interrupt(f, req, &d);
+	err = fuse_fs_iomap_config(f->fs, flags, maxbytes, &cfg);
+	fuse_finish_interrupt(f, req, &d);
+	if (err) {
+		reply_err(req, err);
+		return;
+	}
+
+	fuse_reply_iomap_config(req, &cfg);
+}
+
 static int clean_delay(struct fuse *f)
 {
 	/*
@@ -4738,6 +4774,7 @@ static struct fuse_lowlevel_ops fuse_path_ops = {
 	.iomap_begin = fuse_lib_iomap_begin,
 	.iomap_end = fuse_lib_iomap_end,
 	.iomap_ioend = fuse_lib_iomap_ioend,
+	.iomap_config = fuse_lib_iomap_config,
 };
 
 int fuse_notify_poll(struct fuse_pollhandle *ph)