diff options
| -rw-r--r-- | libfdt/fdt_overlay.c | 1219 |
1 files changed, 689 insertions, 530 deletions
diff --git a/libfdt/fdt_overlay.c b/libfdt/fdt_overlay.c index 52eabd1..d491f00 100644 --- a/libfdt/fdt_overlay.c +++ b/libfdt/fdt_overlay.c @@ -12,6 +12,17 @@ #include "libfdt_internal.h" +#undef DEBUG + +#ifdef DEBUG +#define dprintf(x...) printf(x) +#else +#define dprintf(x...) +#endif + +#define MAX_BUF_SIZE 256 +#define MAX_ULONG ((unsigned long)~0UL) + /** * overlay_get_target_phandle - retrieves the target phandle of a fragment * @fdto: pointer to the device tree overlay blob @@ -392,138 +403,6 @@ static int overlay_fixup_one_phandle(void *fdt, void *fdto, sizeof(phandle_prop)); }; -static int overlay_add_to_local_fixups(void *fdt, const char *value, int len) -{ - const char *path, *fixup_end, *prop, *fixup_str; - uint32_t clen; - uint32_t fixup_len; - char *sep, *endptr; - const char *c; - int poffset, nodeoffset, ret, localfixup_off; - int pathlen, proplen; - char propname[PATH_MAX]; - - localfixup_off = fdt_path_offset(fdt, "/__local_fixups__"); - if (localfixup_off < 0 && localfixup_off == -FDT_ERR_NOTFOUND) - localfixup_off = fdt_add_subnode(fdt, 0, "__local_fixups__"); - - if (localfixup_off < 0) - return localfixup_off; - - while (len > 0) { - fixup_str = value; - - /* Assumes null-terminated properties! */ - fixup_end = memchr(value, '\0', len); - if (!fixup_end) - return -FDT_ERR_BADOVERLAY; - - fixup_len = fixup_end - fixup_str; - - len -= (fixup_len + 1); - value += fixup_len + 1; - - c = path = fixup_str; - sep = memchr(c, ':', fixup_len); - if (!sep || *sep != ':') - return -FDT_ERR_BADOVERLAY; - pathlen = sep - path; - if (pathlen == (fixup_len - 1)) - return -FDT_ERR_BADOVERLAY; - - fixup_len -= (pathlen + 1); - c = path + pathlen + 1; - - sep = memchr(c, ':', fixup_len); - if (!sep || *sep != ':') - return -FDT_ERR_BADOVERLAY; - - prop = c; - proplen = sep - c; - - if (proplen >= PATH_MAX) - return -FDT_ERR_BADOVERLAY; - - /* - * Skip fixups that involves the special 'target' property found - * in overlay fragments such as - * /fragment@0:target:0 - * - * The check for one node in path below is to ensure that we - * handle 'target' properties present otherwise in any other - * node, for ex: - * /fragment@0/__overlay__/xyz:target:0 - */ - - /* Does path have exactly one node? */ - c = path; - clen = pathlen; - if (*c == '/') { - c++; - clen -= 1; - } - - sep = memchr(c, '/', clen); - if (!sep && proplen >= 6 && !strncmp(prop, "target", 6)) - continue; - - memcpy(propname, prop, proplen); - propname[proplen] = 0; - - fixup_len -= (proplen + 1); - c = prop + proplen + 1; - poffset = strtoul(c, &endptr, 10); - - nodeoffset = localfixup_off; - - c = path; - clen = pathlen; - - if (*c == '/') { - c++; - clen -= 1; - } - - while (clen > 0) { - char nodename[PATH_MAX]; - int nodelen, childnode; - - sep = memchr(c, '/', clen); - if (!sep) - nodelen = clen; - else - nodelen = sep - c; - - if (nodelen + 1 >= PATH_MAX) - return -FDT_ERR_BADSTRUCTURE; - memcpy(nodename, c, nodelen); - nodename[nodelen] = 0; - - childnode = fdt_add_subnode(fdt, nodeoffset, nodename); - if (childnode == -FDT_ERR_EXISTS) - childnode = fdt_subnode_offset(fdt, - nodeoffset, nodename); - nodeoffset = childnode; - if (nodeoffset < 0) - return nodeoffset; - - c += nodelen; - clen -= nodelen; - - if (*c == '/') { - c++; - clen -= 1; - } - } - - ret = fdt_appendprop_u32(fdt, nodeoffset, propname, poffset); - if (ret < 0) - return ret; - } - - return 0; -} - /** * overlay_fixup_phandle - Set an overlay phandle to the base one * @fdt: Base Device Tree blob @@ -531,7 +410,6 @@ static int overlay_add_to_local_fixups(void *fdt, const char *value, int len) * @symbols_off: Node offset of the symbols node in the base device tree * @property: Property offset in the overlay holding the list of fixups * @fixups_off: Offset of __fixups__ node in @fdto - * @merge: Both input blobs are overlay blobs that are being merged * * overlay_fixup_phandle() resolves all the overlay phandles pointed * to in a __fixups__ property, and updates them to match the phandles @@ -546,14 +424,13 @@ static int overlay_add_to_local_fixups(void *fdt, const char *value, int len) * Negative error code on failure */ static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off, - int property, int fixups_off, int merge) + int property, int fixups_off) { - const char *value, *total_value; + const char *value; const char *label; - int len, total_len, ret = 0; + int len, ret = 0; - total_value = value = fdt_getprop_by_offset(fdto, property, - &label, &len); + value = fdt_getprop_by_offset(fdto, property, &label, &len); if (!value) { if (len == -FDT_ERR_NOTFOUND) return -FDT_ERR_INTERNAL; @@ -561,8 +438,6 @@ static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off, return len; } - total_len = len; - do { const char *path, *name, *fixup_end; const char *fixup_str = value; @@ -609,35 +484,6 @@ static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off, return ret; } while (len > 0); - /* - * Properties found in __fixups__ node are typically one of - * these types: - * - * abc = "/fragment@2:target:0" (first type) - * abc = "/fragment@2/__overlay__:xyz:0" (second type) - * - * Both types could also be present in some properties as well such as: - * - * abc = "/fragment@2:target:0", "/fragment@2/__overlay__:xyz:0" - * - * While merging two overlay blobs, a successfull overlay phandle fixup - * of second type needs to be recorded in __local_fixups__ node of the - * combined blob, so that the phandle value can be further updated via - * overlay_update_local_references() when the combined overlay blob gets - * overlaid on a different base blob. - * - * Further, since in the case of merging two overlay blobs, we will also - * be merging contents of nodes such as __fixups__ from both overlay - * blobs, delete this property in __fixup__ node, as it no longer - * represents a external phandle reference that needs to be resolved - * during a subsequent overlay of combined blob on a base blob. - */ - if (merge) { - ret = overlay_add_to_local_fixups(fdt, total_value, total_len); - if (!ret) - ret = fdt_delprop(fdto, fixups_off, label); - } - return ret; } @@ -662,12 +508,12 @@ static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off, static int overlay_fixup_phandles(void *fdt, void *fdto, int merge) { int fixups_off, symbols_off; - int property, ret = 0, next_property; + int property, ret = 0; /* We can have overlays without any fixups */ fixups_off = fdt_path_offset(fdto, "/__fixups__"); if (fixups_off == -FDT_ERR_NOTFOUND) - return 0; /* nothing to do */ + return 0; /* nothing to do */ if (fixups_off < 0) return fixups_off; @@ -676,40 +522,13 @@ static int overlay_fixup_phandles(void *fdt, void *fdto, int merge) if ((symbols_off < 0 && (symbols_off != -FDT_ERR_NOTFOUND))) return symbols_off; - /* Safeguard against property being deleted in below loop */ - property = fdt_first_property_offset(fdto, fixups_off); - while (property >= 0) { - next_property = fdt_next_property_offset(fdto, property); + fdt_for_each_property_offset(property, fdto, fixups_off) { ret = overlay_fixup_phandle(fdt, fdto, symbols_off, - property, fixups_off, merge); + property, fixups_off); if (ret && (!merge || ret != -FDT_ERR_NOTFOUND)) return ret; - - if (merge && !ret) { - /* Bail if this was the last property */ - if (next_property < 0) - break; - - /* - * Property is deleted in this case. Next property is - * available at the same offset, so loop back with - * 'property' offset unmodified. Also since @fdt would - * have been modified in this case, refresh the offset - * of /__symbols__ node - */ - symbols_off = fdt_path_offset(fdt, "/__symbols__"); - if (symbols_off < 0) - return symbols_off; - - continue; - } - - property = next_property; } - if (merge && ret == -FDT_ERR_NOTFOUND) - ret = 0; - return ret; } @@ -783,61 +602,176 @@ static int overlay_apply_node(void *fdt, int target, * copy_node - copy a node hierarchically * @fdt - pointer to base device tree * @fdto - pointer to overlay device tree - * @fdt_child - offset of node in overlay device tree which needs to be copied + * @fdto_child - offset of node in overlay device tree which needs to be copied * @fdt_parent - offset of parent node in base tree under which @fdto_child * need to be copied + * @name - if not NULL, (new) name of the child in base device tree + * @skip_fdto_child - if set, skips creation of @fdto_child under @fdt_parent. + * Instead copies everything under @fdto_child to @fdt_parent. * * This function copies a node in overlay tree along with its child-nodes and * their properties, under a given parent node in base tree. */ -static int copy_node(void *fdt, void *fdto, int fdt_parent, int fdto_child) +static int copy_node(void *fdt, void *fdto, int fdt_parent, + int fdto_child, const char *name, int skip_fdto_child) { - const char *name, *value; - int offset, len, ret, prop, child; - void *p; + int len, prop, parent, child; - name = fdt_get_name(fdto, fdto_child, &len); - if (!name) - return len; + if (!skip_fdto_child) { + if (!name) { + name = fdt_get_name(fdto, fdto_child, &len); + if (!name) + return len; + } - offset = fdt_subnode_offset(fdt, fdt_parent, name); - if (offset < 0) { - offset = fdt_add_subnode(fdt, fdt_parent, name); - if (offset < 0) - return offset; - } + parent = fdt_subnode_offset(fdt, fdt_parent, name); + if (parent < 0) { + parent = fdt_add_subnode(fdt, fdt_parent, name); + } - fdt_for_each_subnode(child, fdto, fdto_child) { - ret = copy_node(fdt, fdto, offset, child); - if (ret < 0) - return ret; + if (parent < 0) + return parent; + } else { + parent = fdt_parent; } fdt_for_each_property_offset(prop, fdto, fdto_child) { - int fdt_len = 0; + int ret, fdt_len = 0; + const char *value, *pname; + void *p; - value = fdt_getprop_by_offset(fdto, prop, - &name, &len); + value = fdt_getprop_by_offset(fdto, prop, &pname, &len); + if (!value) + return len; - if (fdt_getprop(fdt, offset, name, &fdt_len)) + if (fdt_getprop(fdt, parent, pname, &fdt_len)) len += fdt_len; - ret = fdt_setprop_placeholder(fdt, offset, name, - len, &p); - if (ret < 0) + ret = fdt_setprop_placeholder(fdt, parent, pname, len, &p); + if (ret) return ret; - if (fdt_len > 0) { - p = (char *)p + fdt_len; - len -= fdt_len; - } - memcpy(p, value, len); } + fdt_for_each_subnode(child, fdto, fdto_child) { + int ret; + + ret = copy_node(fdt, fdto, parent, child, NULL, 0); + if (ret) + return ret; + } + + return 0; +} + +static int get_fragment_name(void *fdto, int fragment, char *name, int namelen) +{ + int len; + const char *nname; + int size = sizeof("fragment@") - 1; + + nname = fdt_get_name(fdto, fragment, &len); + if (!nname) + return len; + + if (len < size || len >= namelen || memcmp(nname, "fragment@", size)) + return -FDT_ERR_BADVALUE; + + memcpy(name, nname, len); + name[len] = 0; + return 0; } +static int get_fragment_index(char *name, unsigned long *idxp) +{ + char *idx; + int size = sizeof("fragment@") - 1; + int len = strlen(name); + char *stop; + unsigned long index; + + if (len < size) + return -FDT_ERR_BADVALUE; + + idx = name + size; + index = strtoul(idx, &stop, 10); + if (*stop != '\0' || stop <= idx) + return -FDT_ERR_BADVALUE; + + *idxp = index; + + return 0; +} + +static int set_new_fragment_name(char *name, int namelen, + unsigned long base_fragment_count) +{ + unsigned long index; + int ret; + + ret = get_fragment_index(name, &index); + if (ret) + return ret; + + if (MAX_ULONG - base_fragment_count < index) + return -FDT_ERR_INTERNAL; + + index += base_fragment_count; + + ret = snprintf(name, namelen, "fragment@%lu", index); + + return ret >= namelen ? -FDT_ERR_INTERNAL : 0; +} + +static int add_phandle(void *fdt, char *node_name, uint32_t phandle) +{ + int offset; + + offset = fdt_subnode_offset(fdt, 0, node_name); + if (offset < 0) + return offset; + + return fdt_setprop_u32(fdt, offset, "phandle", phandle); +} + +static int copy_fragment_to_base(void *fdt, void *fdto, + int fragment, uint32_t *max_phandle, + unsigned long *base_fragment_count) +{ + char name[MAX_BUF_SIZE]; + int ret; + uint32_t target_phandle = *max_phandle; + + ret = get_fragment_name(fdto, fragment, name, sizeof(name)); + if (ret) + return ret; + + ret = set_new_fragment_name(name, sizeof(name), *base_fragment_count); + if (ret) + return ret; + + ret = copy_node(fdt, fdto, 0, fragment, name, 0); + if (ret) + return ret; + + ret = add_phandle(fdt, name, target_phandle); + if (ret) + return ret; + + // Fix target to point to new node in base + ret = fdt_setprop_inplace_u32(fdto, fragment, "target", target_phandle); + if (ret) + return ret; + + return (++(*max_phandle) == UINT32_MAX || + ++(*base_fragment_count) == ULONG_MAX) ? + -FDT_ERR_BADOVERLAY : 0; +} + +static int count_fragments(void *fdt, unsigned long *max_base_fragments); + /** * overlay_merge - Merge an overlay into its base device tree * @fdt: Base Device Tree blob @@ -854,14 +788,24 @@ static int copy_node(void *fdt, void *fdto, int fdt_parent, int fdto_child) * 0 on success * Negative error code on failure */ -static int overlay_merge(void *fdt, void *fdto, int merge) +static int overlay_merge(void *fdt, void *fdto, int merge, + uint32_t *max_phandle) { - int fragment; + int fragment, ret; + unsigned long base_fragment_count = 0; + + if (merge) { + ret = count_fragments(fdt, &base_fragment_count); + /* no fragments in base dtb? then nothing to rename */ + if (ret && ret != -FDT_ERR_NOTFOUND) + return ret; + + base_fragment_count++; + } fdt_for_each_subnode(fragment, fdto, 0) { int overlay; int target; - int ret; /* * Each fragments will have an __overlay__ node. If @@ -876,6 +820,9 @@ static int overlay_merge(void *fdt, void *fdto, int merge) target = fdt_overlay_target_offset(fdt, fdto, fragment, NULL); if (target < 0) { + if (!merge || target != -FDT_ERR_BADPHANDLE) + return target; + /* * No target found which is acceptable situation in case * of merging two overlay blobs. Copy this fragment to @@ -883,12 +830,13 @@ static int overlay_merge(void *fdt, void *fdto, int merge) * overlay during a subsequent overlay operation of * combined blob on another base blob. */ - if (target == -FDT_ERR_BADPHANDLE && merge) { - target = copy_node(fdt, fdto, 0, fragment); - if (!target) - continue; - } - return target; + ret = copy_fragment_to_base(fdt, fdto, fragment, + max_phandle, + &base_fragment_count); + if (ret) + return ret; + + continue; } ret = overlay_apply_node(fdt, target, fdto, overlay); @@ -931,7 +879,6 @@ static int get_path_len(const void *fdt, int nodeoffset) * overlay_symbol_update - Update the symbols of base tree after a merge * @fdt: Base Device Tree blob * @fdto: Device tree overlay blob - * @merge: Both input blobs are overlay blobs that are being merged * * overlay_symbol_update() updates the symbols of the base tree with the * symbols of the applied overlay @@ -944,15 +891,15 @@ static int get_path_len(const void *fdt, int nodeoffset) * 0 on success * Negative error code on failure */ -static int overlay_symbol_update(void *fdt, void *fdto, int merge) +static int overlay_symbol_update(void *fdt, void *fdto, uint32_t max_phandle) { int root_sym, ov_sym, prop, next_prop, path_len, fragment, target; - int len, frag_name_len, ret, rel_path_len; + int len, frag_name_len, ret, rel_path_len, rel_path_len1 = 0; const char *s, *e; const char *path; const char *name; const char *frag_name; - const char *rel_path; + const char *rel_path, *rel_path1 = NULL; const char *target_path; char *buf; void *p; @@ -985,7 +932,8 @@ static int overlay_symbol_update(void *fdt, void *fdto, int merge) return path_len; /* verify it's a string property (terminated by a single \0) */ - if (path_len < 1 || memchr(path, '\0', path_len) != &path[path_len - 1]) + if (path_len < 1 + || memchr(path, '\0', path_len) != &path[path_len - 1]) return -FDT_ERR_BADVALUE; /* keep end marker to avoid strlen() */ @@ -1011,6 +959,11 @@ static int overlay_symbol_update(void *fdt, void *fdto, int merge) /* /<fragment-name>/__overlay__/<relative-subnode-path> */ rel_path = s + len; rel_path_len = e - rel_path - 1; + + if (max_phandle != 0) { + rel_path1 = s + 1; + rel_path_len1 = e - rel_path1 - 1; + } } else if ((e - s) == len && (memcmp(s, "/__overlay__", len - 1) == 0)) { /* /<fragment-name>/__overlay__ */ @@ -1024,7 +977,7 @@ static int overlay_symbol_update(void *fdt, void *fdto, int merge) /* find the fragment index in which the symbol lies */ ret = fdt_subnode_offset_namelen(fdto, 0, frag_name, - frag_name_len); + frag_name_len); /* not found? */ if (ret < 0) return -FDT_ERR_BADOVERLAY; @@ -1037,14 +990,20 @@ static int overlay_symbol_update(void *fdt, void *fdto, int merge) /* get the target of the fragment */ ret = fdt_overlay_target_offset(fdt, fdto, fragment, &target_path); - if (ret < 0) { - if (ret == -FDT_ERR_BADPHANDLE && merge) { - prop = next_prop; - continue; - } - + if (ret < 0) return ret; + + if (rel_path1) { + uint32_t phandle = + overlay_get_target_phandle(fdto, fragment); + int base_symbol_found = (phandle < max_phandle); + + if (!base_symbol_found) { + rel_path = rel_path1; + rel_path_len = rel_path_len1; + } } + target = ret; /* if we have a target path use */ @@ -1058,20 +1017,23 @@ static int overlay_symbol_update(void *fdt, void *fdto, int merge) } ret = fdt_setprop_placeholder(fdt, root_sym, name, - len + (len > 1) + rel_path_len + 1, &p); + len + (len > + 1) + rel_path_len + 1, &p); if (ret < 0) return ret; if (!target_path) { /* again in case setprop_placeholder changed it */ - ret = fdt_overlay_target_offset(fdt, fdto, fragment, &target_path); + ret = + fdt_overlay_target_offset(fdt, fdto, fragment, + &target_path); if (ret < 0) return ret; target = ret; } buf = p; - if (len > 1) { /* target is not root */ + if (len > 1) { /* target is not root */ if (!target_path) { ret = fdt_get_path(fdt, target, buf, len + 1); if (ret < 0) @@ -1086,29 +1048,6 @@ static int overlay_symbol_update(void *fdt, void *fdto, int merge) memcpy(buf + len + 1, rel_path, rel_path_len); buf[len + 1 + rel_path_len] = '\0'; - /* - * In case of merging two overlay blobs, we will be merging - * contents of nodes such as __symbols__ from both overlay - * blobs. Delete this property in __symbols__ node of second - * overlay blob, as it has already been reflected in - * first/combined blob's __symbols__ node. - */ - if (merge) { - ret = fdt_delprop(fdto, ov_sym, name); - if (ret < 0) - return ret; - - /* Bail if this was the last property */ - if (next_prop < 0) - break; - - /* - * Continue with same 'prop' offset, as the next - * property is now available at the same offset - */ - continue; - } - prop = next_prop; } @@ -1139,7 +1078,7 @@ int fdt_overlay_apply(void *fdt, void *fdto) if (ret) goto err; - ret = overlay_merge(fdt, fdto, 0); + ret = overlay_merge(fdt, fdto, 0, NULL); if (ret) goto err; @@ -1169,333 +1108,545 @@ err: return ret; } -/* - * Property value could be in this format - * fragment@M ...fragment@N....fragment@O.. - * - * This needs to be converted to - * fragment@M+delta...fragment@N+delta....fragment@O+delta - */ -static int rename_fragments_in_property(void *fdto, int offset, - int property, int delta) +/* Return maximum count of overlay fragments */ +static int count_fragments(void *fdt, unsigned long *max_base_fragments) { - char *start, *sep, *end, *stop, *value; - int needed = 0, ret, len, found = 0, available, diff; - unsigned long index, new_index; - void *p = NULL; - const char *label; + int offset = -1, child_offset, child_len, len, found = 0; + const char *name, *child_name, *idx; + char *stop; + unsigned long index, max = 0; - value = (char *)(uintptr_t)fdt_getprop_by_offset(fdto, property, - &label, &len); - if (!value) - return len; + offset = fdt_first_subnode(fdt, 0); + while (offset >= 0) { + name = fdt_get_name(fdt, offset, &len); + if (!name) + return len; - start = value; - end = value + len; + if (len < 9 || memcmp(name, "fragment@", 9)) + goto next_node; - /* Find the required additional space */ - while (start < end) { - sep = memchr(start, '@', (end - start)); - if (!sep) { - needed += end - start; - break; - } + child_offset = fdt_first_subnode(fdt, offset); + if (child_offset < 0) + return child_offset; - /* Check if string "fragment" exists */ - sep -= 8; + child_name = fdt_get_name(fdt, child_offset, &child_len); + if (!child_name) + return child_len; - if (sep < start || strncmp(sep, "fragment", 8)) { - /* Start scan again after '@' */ - sep = sep + 9; - needed += (sep - start); - start = sep; - continue; - } + if (child_len < 11 || memcmp(child_name, "__overlay__", 11)) + goto next_node; found = 1; - sep += 9; - needed += (sep - start); - index = strtoul(sep, &stop, 10); - if (ULONG_MAX - index < delta) - return -FDT_ERR_BADVALUE; - - new_index = index + delta; - needed += snprintf(NULL, 0, "%lu", new_index); - start = stop; + idx = name + 9; + index = strtoul(idx, &stop, 10); + if (index > max) + max = index; +next_node: + offset = fdt_next_subnode(fdt, offset); } if (!found) - return 0; + return -FDT_ERR_NOTFOUND; - p = value; - if (needed > len) { - ret = fdt_setprop_placeholder(fdto, offset, label, needed, &p); - if (ret < 0) - return ret; - } + *max_base_fragments = max; - start = p; - end = start + len; - ret = 0; + return 0; +} - while (start < end) { - sep = memchr(start, '@', (end - start)); - if (!sep) - break; +static int find_add_subnode(void *fdt, int parent_off, char *node_name) +{ + int offset; - /* Check if string "fragment" exists */ - sep -= 8; - if (sep < start || strncmp(sep, "fragment", 8)) { - /* Start scan again after '@' */ - start = sep + 9; - continue; - } + offset = fdt_subnode_offset(fdt, parent_off, node_name); - sep += 9; - index = strtoul(sep, &stop, 10); - new_index = index + delta; + if (offset < 0) + offset = fdt_add_subnode(fdt, parent_off, node_name); - needed = snprintf(NULL, 0, "%lu", new_index); - available = stop - sep; + return offset; +} - if (available < needed) { - diff = needed - available; - memmove(stop + diff, stop, (end - stop)); - end += diff; - } +static int prop_exists_in_node(void *fdt, char *path, const char *prop_name) +{ + int offset; + const void *val; - { - /* +1 for NULL char */ - char buf[needed + 1]; + offset = fdt_path_offset(fdt, path); + if (offset < 0) + return 0; - snprintf(buf, needed + 1, "%lu", new_index); - memcpy(sep, buf, needed); - } + val = fdt_getprop(fdt, offset, prop_name, NULL); - start = sep + needed; - } + return val != NULL; +} - return 0; +static void *get_next_component(const char **p, int *len, char sep) +{ + char *q; + int consumed; + + q = memchr(*p, sep, *len); + if (!q) + return NULL; + + q++; + + // 1 for ':' + consumed = (q - *p); + if (*len <= consumed) + return NULL; + + *len -= consumed; + *p = q; + + return q; } -/** - * rename_fragments_in_node - Rename fragment@xyz instances in a node's - * properties - * - * @fdto - pointer to a device-tree blob - * @nodename - Node in whose properties fragments need to be renamed - * @delta - Increment to be applied to fragment index - */ -static int rename_fragments_in_node(void *fdto, const char *nodename, - unsigned long delta) +static int lookup_target_path(void *fdt, void *fdto, const char *fragment, + int frag_name_len, char *buf, int buf_len, + int *target_phandle) { - int offset, property; - int ret; + int offset, ret, target, len; + const char *target_path; + static const char fragstr[] = "fragment"; + int fragstrlen = sizeof(fragstr) - 1; - offset = fdt_path_offset(fdto, nodename); - if (offset < 0) - return offset; + memset(buf, 0, buf_len); + + if (frag_name_len < fragstrlen || memcmp(fragment, fragstr, fragstrlen)) + return -FDT_ERR_BADOVERLAY; + + /* find the fragment index in which the symbol lies */ + ret = fdt_subnode_offset_namelen(fdto, 0, fragment, frag_name_len); + /* not found? */ + if (ret < 0) + return -FDT_ERR_BADOVERLAY; + + offset = ret; - fdt_for_each_property_offset(property, fdto, offset) { - ret = rename_fragments_in_property(fdto, offset, - property, delta); + /* an __overlay__ subnode must exist */ + ret = fdt_subnode_offset(fdto, offset, "__overlay__"); + if (ret < 0) + return -FDT_ERR_BADOVERLAY; + + /* get the target of the fragment */ + ret = fdt_overlay_target_offset(fdt, fdto, offset, &target_path); + if (ret < 0) + return ret; + + target = ret; + if (target_phandle) + *target_phandle = ret; + + /* if we have a target path use */ + if (!target_path) { + ret = get_path_len(fdt, target); if (ret < 0) return ret; + len = ret; + } else { + len = strlen(target_path); + } + if (len >= buf_len) + return -FDT_ERR_INTERNAL; + + if (len > 1) { /* target is not root */ + if (!target_path) { + ret = fdt_get_path(fdt, target, buf, len + 1); + if (ret < 0) + return ret; + } else + memcpy(buf, target_path, len + 1); + } return 0; } -/** - * rename_nodes - Rename all fragement@xyz nodes - * - * @fdto - pointer to device-tree blob - * @parent_node - node offset of parent whose child fragment nodes need to be - * renamed - * @delta - increment to be added to fragment number - */ -static int rename_nodes(void *fdto, int parent_node, unsigned long delta) +static int fixup_snippet_update(void *fdt, void *fdto, const char *snippet, + int snippet_len, char *buf, int buflen, + int *ignore, int base_symbol_found, + uint32_t max_phandle) { - int offset = -1, ret, len, strsize; - int child_len, child_offset; - const char *name, *child_name, *idx; - char *stop = NULL; - unsigned long index, new_index; + const char *snippet_o = snippet; + const char *path, *fragment, *prop_name, *prop_val, *rel_path; + char *sep; + int snippet_len_o = snippet_len, fragment_len, rel_path_len; + int prop_len, path_len, rem, ret; + static const char tprop[] = "target"; + static const char frag[] = "/fragment"; + static const char olay[] = "/__overlay__"; + + /* Validate format: + * path_to_node : prop_name : prop_offset + */ + path = snippet; + prop_name = get_next_component(&snippet, &snippet_len, ':'); + if (!prop_name) + return -FDT_ERR_BADOVERLAY; - offset = fdt_first_subnode(fdto, parent_node); - while (offset >= 0) { - name = fdt_get_name(fdto, offset, &len); - if (!name) - return len; + prop_val = get_next_component(&snippet, &snippet_len, ':'); + if (!prop_val) + return -FDT_ERR_BADOVERLAY; - if (len < 9 || strncmp(name, "fragment@", 9)) - goto next_node; + path_len = prop_name - path - 1; // 1 for ':' + prop_len = prop_val - prop_name - 1; // 1 for ':' - child_offset = fdt_first_subnode(fdto, offset); - if (child_offset < 0) - return child_offset; + if (path_len < sizeof(frag) - 1 || memcmp(path, frag, sizeof(frag) - 1)) + return -FDT_ERR_BADOVERLAY; - child_name = fdt_get_name(fdto, child_offset, &child_len); - if (!child_name) - return child_len; + if (base_symbol_found && + prop_len == sizeof(tprop) - 1 && + !memcmp(prop_name, tprop, sizeof(tprop) - 1)) { + *ignore = 1; + return 0; + } - /* Extra FDT_TAGSIZE bytes for expanded node name */ - strsize = FDT_TAGALIGN(len+1+FDT_TAGSIZE); + fragment = path; + // check if there is a '/' besides the first one in node_path + sep = memchr(fragment + 1, '/', path_len - 1); + if (sep) { + int fragment_target_found = 0; + + fragment_len = sep - fragment; + path_len -= (sep - fragment); + if (path_len < sizeof(olay) - 1 + || memcmp(sep, olay, sizeof(olay) - 1)) + return -FDT_ERR_BADOVERLAY; - if (child_len >= 11 && - !strncmp(child_name, "__overlay__", 11)) { - char new_name[strsize]; + int frag_offset; - idx = name + 9; - stop = NULL; - index = strtoul(idx, &stop, 10); - if (ULONG_MAX - delta < index) - return -FDT_ERR_BADVALUE; + frag_offset = + fdt_subnode_offset_namelen(fdto, 0, fragment + 1, + fragment_len - 1); + if (frag_offset < 0) + return -FDT_ERR_BADOVERLAY; - new_index = index + delta; - ret = snprintf(new_name, sizeof(new_name), - "fragment@%lu", new_index); - if (ret >= sizeof(new_name)) - return -FDT_ERR_BADVALUE; + /* an __overlay__ subnode must exist */ + ret = + fdt_subnode_offset(fdto, frag_offset, + "__overlay__"); + if (ret < 0) + return -FDT_ERR_BADOVERLAY; - ret = fdt_set_name(fdto, offset, new_name); + /* get the target of the fragment */ + ret = overlay_get_target(fdt, fdto, frag_offset, NULL); if (ret < 0) return ret; + + fragment_target_found = (ret < max_phandle); } -next_node: - offset = fdt_next_subnode(fdto, offset); + if (fragment_target_found) + rel_path = sep + sizeof(olay) - 1; + else + rel_path = sep; + } else { + rel_path = fragment + path_len; + fragment_len = path_len; } + rel_path_len = snippet_len_o - (rel_path - snippet_o); + + if (rel_path_len <= 0 || fragment_len >= buflen) + return -FDT_ERR_INTERNAL; + + ret = + lookup_target_path(fdt, fdto, fragment + 1, fragment_len - 1, buf, + buflen, NULL); + if (ret) + return ret; + + rem = buflen - strlen(buf); + if (rel_path_len >= rem) + return -FDT_ERR_INTERNAL; + + sep = buf + strlen(buf); + memcpy(sep, rel_path, rel_path_len); return 0; } -/* Return maximum count of overlay fragments */ -static int count_fragments(void *fdt, unsigned long *max_base_fragments) +static const char *next_snippet(const char **prop, + int *prop_len, int *snippet_len) { - int offset = -1, child_offset, child_len, len, found = 0; - const char *name, *child_name, *idx; - char *stop; - unsigned long index, max = 0; + const char *next = *prop; + const char *tmp; + int len; - offset = fdt_first_subnode(fdt, 0); - while (offset >= 0) { - name = fdt_get_name(fdt, offset, &len); - if (!name) - return len; + if (*prop_len <= 0) + return NULL; - if (len < 9 || strncmp(name, "fragment@", 9)) - goto next_node; + tmp = memchr(next, '\0', *prop_len); + if (!tmp) + return NULL; - child_offset = fdt_first_subnode(fdt, offset); - if (child_offset < 0) - return child_offset; + tmp++; - child_name = fdt_get_name(fdt, child_offset, &child_len); - if (!child_name) - return child_len; + len = tmp - next; + *snippet_len = len; + *prop += len; + *prop_len -= len; - if (child_len < 11 || strncmp(child_name, "__overlay__", 11)) - goto next_node; + return next; +} - found = 1; - idx = name + 9; - index = strtoul(idx, &stop, 10); - if (index > max) - max = index; -next_node: - offset = fdt_next_subnode(fdt, offset); - } +static int add_to_fixups(void *fdt, char *v, const char *label) +{ + const char *val; + char *p; + int vlen = strlen(v) + 1; // 1 for NULL + int len, ret; + int root_fixup; - if (!found) - return -FDT_ERR_NOTFOUND; + root_fixup = fdt_subnode_offset(fdt, 0, "__fixups__"); + if (root_fixup == -FDT_ERR_NOTFOUND) + root_fixup = fdt_add_subnode(fdt, 0, "__fixups__"); - *max_base_fragments = max; + if (root_fixup < 0) + return root_fixup; + + val = fdt_getprop(fdt, root_fixup, label, &len); + if (val) + vlen += len; + + ret = fdt_setprop_placeholder(fdt, root_fixup, label, + vlen, (void **)&p); + if (ret) + return ret; + + if (val) { + p += len; + vlen -= len; + } + memcpy(p, v, vlen); return 0; } -/* - * Merging two overlay blobs involves copying some of the overlay fragment nodes - * (named as fragment@xyz) from second overlay blob into first, which can lead - * to naming conflicts (ex: two nodes of same name /fragment@0). To prevent such - * naming conflicts, rename all occurences of fragment@xyz in second overlay - * blob as fragment@xyz+delta, where delta is the maximum overlay fragments seen - * in first overlay blob - */ -static int overlay_rename_fragments(void *fdt, void *fdto) +static int fdt_find_add_node(void *fdt, int parent_off, char *node) { - int ret, local_offset; - unsigned long max_base_fragments = 0; + int offset; - ret = count_fragments(fdt, &max_base_fragments); - /* no fragments in base dtb? then nothing to rename */ - if (ret == -FDT_ERR_NOTFOUND) - return 0; - else if (ret < 0) - return ret; + offset = fdt_subnode_offset(fdt, parent_off, node); + if (offset < 0) + offset = fdt_add_subnode(fdt, parent_off, node); - max_base_fragments += 1; - ret = rename_nodes(fdto, 0, max_base_fragments); - if (ret < 0) - return ret; + return offset; +} - ret = rename_fragments_in_node(fdto, "/__fixups__", max_base_fragments); - if (ret < 0) - return ret; +/* path => /abc/def/ghi */ +static const char *next_node(const char **path, int *path_len, int *node_len) +{ + const char *sep = *path, *node; - ret = rename_fragments_in_node(fdto, "/__symbols__", - max_base_fragments); - if (ret < 0 && ret != -FDT_ERR_NOTFOUND) - return ret; + if (*sep != '/' || *path_len <= 0) + return NULL; - /* - * renaming fragments in __local_fixups__ node's properties should be - * covered by rename_nodes() + *path = *path + 1; + node = *path; + *path_len = *path_len - 1; + + sep = memchr(node, '/', *path_len); + if (sep) + *node_len = sep - node; + else + *node_len = *path_len; + + *path_len -= *node_len; + *path += *node_len; + + return node; +} + +static int convert_to_u32(const char *p, uint32_t *val) +{ + char *endptr; + unsigned long prop_val; + + prop_val = strtoul(p, &endptr, 10); + if ((*endptr != '\0') || (endptr <= p)) + return -FDT_ERR_BADOVERLAY; + + *val = prop_val; // size mis-match? + + return 0; +} + +static int add_to_local_fixups(void *fdt, const char *snippet) +{ + const char *path, *prop_name, *prop_val, *node; + int path_len, parent, ret, node_len, prop_len = 0; + int snippet_len = strlen(snippet); + uint32_t val = 0; + char buf[MAX_BUF_SIZE]; + + /* Validate format: + * path_to_node : prop_name : prop_offset + * OR + * path_to_node */ - local_offset = fdt_path_offset(fdto, "/__local_fixups__"); - if (local_offset >= 0) - ret = rename_nodes(fdto, local_offset, max_base_fragments); + path = snippet; + prop_name = get_next_component(&snippet, &snippet_len, ':'); + if (prop_name) { + prop_val = get_next_component(&snippet, &snippet_len, ':'); + if (!prop_val) + return -FDT_ERR_BADOVERLAY; - if (ret == -FDT_ERR_NOTFOUND) - ret = 0; + path_len = prop_name - path - 1; // 1 for ':' + prop_len = prop_val - prop_name - 1; // 1 for ':' - return ret; + ret = convert_to_u32(prop_val, &val); + if (ret) + return ret; + } else + path_len = strlen(snippet); + + parent = fdt_find_add_node(fdt, 0, "__local_fixups__"); + if (parent < 0) + return parent; + + while ((node = next_node(&path, &path_len, &node_len))) { + int offset; + + offset = + fdt_subnode_offset_namelen(fdt, parent, node, node_len); + if (offset < 0) + offset = + fdt_add_subnode_namelen(fdt, parent, node, + node_len); + if (offset < 0) + return offset; + parent = offset; + } + + if (!prop_name) + return parent; + + if (prop_len >= sizeof(buf)) + return -FDT_ERR_INTERNAL; + memcpy(buf, prop_name, prop_len); + buf[prop_len] = 0; + if (ret >= prop_len) + return -FDT_ERR_INTERNAL; + + return fdt_appendprop_u32(fdt, parent, buf, val); } -/* merge a node's properties from fdto to fdt */ -static int overlay_merge_node_properties(void *fdt, - void *fdto, const char *nodename) +static int overlay_fixups_update(void *fdt, void *fdto, uint32_t max_phandle) { - int fdto_offset, ret; + int ov_fixup, root_fixup, prop; - fdto_offset = fdt_path_offset(fdto, nodename); - if (fdto_offset < 0) - return fdto_offset; + ov_fixup = fdt_subnode_offset(fdto, 0, "__fixups__"); + if (ov_fixup < 0) + return 0; - ret = copy_node(fdt, fdto, 0, fdto_offset); + root_fixup = find_add_subnode(fdt, 0, "__fixups__"); + if (root_fixup < 0) + return root_fixup; - return ret; + fdt_for_each_property_offset(prop, fdto, ov_fixup) { + int snippet_len, prop_len, base_symbol_found; + const char *label, *snippet, *prop_val; + + prop_val = fdt_getprop_by_offset(fdto, prop, &label, &prop_len); + if (prop_val == NULL) + return -FDT_ERR_BADOVERLAY; + + base_symbol_found = + prop_exists_in_node(fdt, "/__symbols__", label); + dprintf + ("%s: Checking prop label %s val %s base_symbol_found %d\n", + __func__, label, prop_val, base_symbol_found); + + while ((snippet = + next_snippet(&prop_val, &prop_len, &snippet_len))) { + char new_val[MAX_BUF_SIZE]; + int ignore = 0, ret; + + ret = + fixup_snippet_update(fdt, fdto, snippet, + snippet_len, new_val, + sizeof(new_val), &ignore, + base_symbol_found, + max_phandle); + dprintf + ("%s: fixup_snippet %s new_val %s ret %d ignore %d\n", + __func__, snippet, new_val, ret, ignore); + if (ret) + return ret; + + if (ignore) + continue; + + if (!base_symbol_found) + ret = add_to_fixups(fdt, new_val, label); + else + ret = add_to_local_fixups(fdt, new_val); + + if (ret) + return ret; + } + } + + return 0; } -static int overlay_merge_local_fixups(void *fdt, void *fdto) +static int overlay_local_fixups_update(void *fdt, void *fdto, + uint32_t max_phandle) { - int fdto_local_fixups, ret; + int ov_lfixups, root_lfixups, node, ret; - fdto_local_fixups = fdt_path_offset(fdto, "/__local_fixups__"); - if (fdto_local_fixups < 0) - return fdto_local_fixups; + ov_lfixups = fdt_subnode_offset(fdto, 0, "__local_fixups__"); + if (ov_lfixups == -FDT_ERR_NOTFOUND) + return 0; - ret = copy_node(fdt, fdto, 0, fdto_local_fixups); + root_lfixups = fdt_subnode_offset(fdt, 0, "__local_fixups__"); + if (root_lfixups == -FDT_ERR_NOTFOUND) + root_lfixups = fdt_add_subnode(fdt, 0, "__local_fixups__"); - return ret; + if (root_lfixups < 0) + return root_lfixups; + + fdt_for_each_subnode(node, fdto, ov_lfixups) { + int len, child_node, target_phandle, parent_node; + int skip_fdto_child = 0; + int base_symbol_found; + const char *name = fdt_get_name(fdto, node, &len); + char buf[MAX_BUF_SIZE]; + + ret = lookup_target_path(fdt, fdto, name, strlen(name), + buf, sizeof(buf), &target_phandle); + if (ret) + return ret; + + base_symbol_found = !(target_phandle >= max_phandle); + + parent_node = add_to_local_fixups(fdt, buf); + if (parent_node < 0) + return parent_node; + + child_node = fdt_subnode_offset(fdto, node, "__overlay__"); + if (child_node < 0) + return -FDT_ERR_BADOVERLAY; + + if (base_symbol_found) + skip_fdto_child = 1; + + ret = copy_node(fdt, fdto, parent_node, child_node, + NULL, skip_fdto_child); + if (ret) + return ret; + } + + return 0; } int fdt_overlay_merge(void *fdt, void *fdto, int *fdto_nospace) { uint32_t delta = fdt_get_max_phandle(fdt); + uint32_t delta0 = fdt_get_max_phandle(fdto); + uint32_t max_phandle; int ret; fdt_check_header(fdt); @@ -1503,45 +1654,52 @@ int fdt_overlay_merge(void *fdt, void *fdto, int *fdto_nospace) *fdto_nospace = 0; - ret = overlay_rename_fragments(fdt, fdto); + if (UINT32_MAX - delta < delta0) + return -FDT_ERR_BADOVERLAY; + max_phandle = delta + delta0 + 1; + dprintf("delta %u max_phandle %u\n", delta, max_phandle); + + ret = overlay_adjust_local_phandles(fdto, delta); + dprintf("adjust_local_phandles %d\n", ret); if (ret) { if (ret == -FDT_ERR_NOSPACE) *fdto_nospace = 1; goto err; } - ret = overlay_adjust_local_phandles(fdto, delta); - if (ret) - goto err; - ret = overlay_update_local_references(fdto, delta); - if (ret) + dprintf("update_local_references %d\n", ret); + if (ret) { + if (ret == -FDT_ERR_NOSPACE) + *fdto_nospace = 1; goto err; + } ret = overlay_fixup_phandles(fdt, fdto, 1); - if (ret) - goto err; - - ret = overlay_merge(fdt, fdto, 1); - if (ret) + dprintf("fixup_phandles %d\n", ret); + if (ret && ret != -FDT_ERR_NOTFOUND) goto err; - ret = overlay_symbol_update(fdt, fdto, 1); + ret = overlay_merge(fdt, fdto, 1, &max_phandle); + dprintf("overlay_merge %d\n", ret); if (ret) goto err; - /* Can't have an overlay without __fixups__ ? */ - ret = overlay_merge_node_properties(fdt, fdto, "/__fixups__"); + /* local_fixups node is optional */ + max_phandle = delta + delta0 + 1; + ret = overlay_symbol_update(fdt, fdto, max_phandle); + dprintf("overlay_symbol_update %d\n", ret); if (ret) goto err; - /* __symbols__ node need not be present */ - ret = overlay_merge_node_properties(fdt, fdto, "/__symbols__"); - if (ret && ret != -FDT_ERR_NOTFOUND) + /* fixups node is optional */ + ret = overlay_fixups_update(fdt, fdto, max_phandle); + dprintf("overlay_fixups_update %d\n", ret); + if (ret < 0 && ret != -FDT_ERR_NOTFOUND) goto err; - /* __local_fixups__ node need not be present */ - ret = overlay_merge_local_fixups(fdt, fdto); + ret = overlay_local_fixups_update(fdt, fdto, max_phandle); + dprintf("overlay_local_fixups_update %d\n", ret); if (ret < 0 && ret != -FDT_ERR_NOTFOUND) goto err; @@ -1550,6 +1708,7 @@ int fdt_overlay_merge(void *fdt, void *fdto, int *fdto_nospace) */ fdt_set_magic(fdto, ~0); + dprintf("overlay_merge completed successfully!\n"); return 0; err: |