DAOS-15682 dfuse: Perform reads in larger chunks.

src/client/dfuse/dfuse.h

@@ -405,6 +405,7 @@ struct dfuse_event {
 	union {
 		struct dfuse_obj_hdl     *de_oh;
 		struct dfuse_inode_entry *de_ie;
+		struct read_chunk_data   *de_cd;
 	};
 	off_t  de_req_position; /**< The file position requested by fuse */
 	union {
@@ -1011,6 +1012,8 @@ struct dfuse_inode_entry {
 
 	/* Entry on the evict list */
 	d_list_t                  ie_evict_entry;
+
+	struct read_chunk_core   *ie_chunk;
 };
 
 /* Flush write-back cache writes to a inode.  It does this by waiting for and then releasing an
@@ -1108,6 +1111,13 @@ dfuse_compute_inode(struct dfuse_cont *dfs,
 void
 dfuse_cache_evict_dir(struct dfuse_info *dfuse_info, struct dfuse_inode_entry *ie);
 
+/* Free any read chunk data for an inode.
+ *
+ * Returns true if feature was used.
+ */
+bool
+read_chunk_close(struct dfuse_inode_entry *ie);
+
 /* Metadata caching functions. */
 
 /* Mark the cache as up-to-date from now */

src/client/dfuse/ops/open.c

@@ -139,6 +139,7 @@ dfuse_cb_release(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 	struct dfuse_obj_hdl     *oh         = (struct dfuse_obj_hdl *)fi->fh;
 	struct dfuse_inode_entry *ie         = NULL;
 	int                       rc;
+	uint32_t                  oc;
 	uint32_t                  il_calls;
 
 	/* Perform the opposite of what the ioctl call does, always change the open handle count
@@ -206,7 +207,11 @@ dfuse_cb_release(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 	if (il_calls != 0) {
 		atomic_fetch_sub_relaxed(&oh->doh_ie->ie_il_count, 1);
 	}
-	atomic_fetch_sub_relaxed(&oh->doh_ie->ie_open_count, 1);
+	oc = atomic_fetch_sub_relaxed(&oh->doh_ie->ie_open_count, 1);
+	if (oc == 1) {
+		if (read_chunk_close(oh->doh_ie))
+			oh->doh_linear_read = true;
+	}
 
 	if (oh->doh_evict_on_close) {
 		ie = oh->doh_ie;