svn commit: r327416 - head/stand/fdt

[Kyle Evans]

Author: kevans
Date: Sun Dec 31 05:22:26 2017
New Revision: 327416
URL: https://svnweb.freebsd.org/changeset/base/327416

Log:
  stand/fdt: Make fdt_overlay_apply signature-compatible with libfdt
  
  libfdt will assume a writable fdt overlay blob has been passed in, so make
  ours compatible to allow easier review when we try to drop libfdt into
  place. overlay from the calling context is writable, making it safe to
  simply rip out everything related to copying the overlay blob in
  fdt_overlay_apply.
  
  I note here that we still have problems: fdt_overlay_apply, both our version
  and libfdt's, may fail and have already clobbered the base fdt to some
  extent. Future work will make sure we don't apply a potentially bogus fdt,
  instead discarding the base fdt if we had an error.
  
  Reviewed by:	gonzo
  Differential Revision:	https://reviews.freebsd.org/D13695

Modified:
  head/stand/fdt/fdt_loader_cmd.c
  head/stand/fdt/fdt_overlay.c
  head/stand/fdt/fdt_overlay.h

Modified: head/stand/fdt/fdt_loader_cmd.c
==============================================================================
--- head/stand/fdt/fdt_loader_cmd.c	Sun Dec 31 05:16:23 2017	(r327415)
+++ head/stand/fdt/fdt_loader_cmd.c	Sun Dec 31 05:22:26 2017	(r327416)
@@ -386,7 +386,8 @@ fdt_apply_overlays()
 	for (fp = file_findfile(NULL, "dtbo"); fp != NULL; fp = fp->f_next) {
 		printf("applying DTB overlay '%s'\n", fp->f_name);
 		COPYOUT(fp->f_addr, overlay, fp->f_size);
-		fdt_overlay_apply(new_fdtp, overlay, fp->f_size);
+		/* Both overlay and new_fdtp may be modified in place */
+		fdt_overlay_apply(new_fdtp, overlay);
 	}
 
 	free(fdtp);

Modified: head/stand/fdt/fdt_overlay.c
==============================================================================
--- head/stand/fdt/fdt_overlay.c	Sun Dec 31 05:16:23 2017	(r327415)
+++ head/stand/fdt/fdt_overlay.c	Sun Dec 31 05:22:26 2017	(r327416)
@@ -409,41 +409,23 @@ fdt_overlay_apply_fragments(void *main_fdtp, void *ove
 }
 
 int
-fdt_overlay_apply(void *main_fdtp, void *overlay_fdtp, size_t overlay_length)
+fdt_overlay_apply(void *main_fdtp, void *overlay_fdtp)
 {
-	void *overlay_copy;
-	int rv;
 
-	rv = 0;
-
-	/* We modify overlay in-place, so we need writable copy */
-	overlay_copy = malloc(overlay_length);
-	if (overlay_copy == NULL) {
-		printf("failed to allocate memory for overlay copy\n");
+	if (fdt_overlay_do_fixups(main_fdtp, overlay_fdtp) < 0) {
+		printf("failed to perform fixups in overlay\n");
 		return (-1);
 	}
 
-	memcpy(overlay_copy, overlay_fdtp, overlay_length);
-
-	if (fdt_overlay_do_fixups(main_fdtp, overlay_copy) < 0) {
-		printf("failed to perform fixups in overlay\n");
-		rv = -1;
-		goto out;
-	}
-
-	if (fdt_overlay_do_local_fixups(main_fdtp, overlay_copy) < 0) {
+	if (fdt_overlay_do_local_fixups(main_fdtp, overlay_fdtp) < 0) {
 		printf("failed to perform local fixups in overlay\n");
-		rv = -1;
-		goto out;
+		return (-1);
 	}
 
-	if (fdt_overlay_apply_fragments(main_fdtp, overlay_copy) < 0) {
+	if (fdt_overlay_apply_fragments(main_fdtp, overlay_fdtp) < 0) {
 		printf("failed to apply fragments\n");
-		rv = -1;
+		return (-1);
 	}
 
-out:
-	free(overlay_copy);
-
-	return (rv);
+	return (0);
 }

Modified: head/stand/fdt/fdt_overlay.h
==============================================================================
--- head/stand/fdt/fdt_overlay.h	Sun Dec 31 05:16:23 2017	(r327415)
+++ head/stand/fdt/fdt_overlay.h	Sun Dec 31 05:22:26 2017	(r327416)
@@ -29,6 +29,6 @@
 #ifndef FDT_OVERLAY_H
 #define FDT_OVERLAY_H
 
-int fdt_overlay_apply(void *main_fdtp, void *overlay_fdtp, size_t overlay_length);
+int fdt_overlay_apply(void *main_fdtp, void *overlay_fdtp);
 
 #endif /* FDT_OVERLAY_H */