Incremental depmod

.gitignore

@@ -34,3 +34,8 @@
 .*.swp
 cscope.out
 tags
+__pycache__
+testsuite/module-playground/ex-*.c
+testsuite/module-playground/gen_mod.mak
+testsuite/module-playground/symvers
+

libkmod/libkmod-index.c

@@ -395,20 +395,18 @@
 	return NULL;
 }
 
-static void index_dump_node(struct index_node_f *node, struct strbuf *buf,
-			    struct wrtbuf *wbuf)
+static void index_walk_node(struct index_node_f *node, struct strbuf *buf,
+			    index_walk_cb *callback, void *arg)
 {
 	struct index_value *v;
 	size_t pushed;
+	const char *key;
 
 	pushed = strbuf_pushchars(buf, node->prefix);
+	key = strbuf_str(buf);
 
-	for (v = node->values; v != NULL; v = v->next) {
-		wrtbuf_write(wbuf, buf->bytes, strbuf_used(buf));
-		wrtbuf_write(wbuf, " ", 1);
-		wrtbuf_write(wbuf, v->value, strlen(v->value));
-		wrtbuf_write(wbuf, "\n", 1);
-	}
+	for (v = node->values; v != NULL; v = v->next)
+		callback(key, v->value, v->len, v->priority, arg);
 
 	for (uint8_t ch = node->first; ch <= node->last; ch++) {
 		struct index_node_f *child = index_readchild(node, ch);
@@ -417,7 +415,7 @@
 			continue;
 
 		if (strbuf_pushchar(buf, ch)) {
-			index_dump_node(child, buf, wbuf);
+			index_walk_node(child, buf, callback, arg);
 			strbuf_popchar(buf);
 		}
 	}
@@ -426,19 +424,37 @@
 	index_close(node);
 }
 
-void index_dump(struct index_file *in, int fd, bool alias_prefix)
+void index_walk(struct index_file *in, bool alias_prefix, index_walk_cb *callback,
+		void *arg)
 {
 	DECLARE_STRBUF_WITH_STACK(buf, 128);
 	struct index_node_f *root;
-	struct wrtbuf wbuf;
 
 	root = index_readroot(in);
 	if (root == NULL)
 		return;
 
-	wrtbuf_init(&wbuf, fd);
 	if (!alias_prefix || strbuf_pushchars(&buf, "alias "))
-		index_dump_node(root, &buf, &wbuf);
+		index_walk_node(root, &buf, callback, arg);
+}
+
+static void index_dump_cb(const char *key, const char *str, unsigned int len,
+			  unsigned int priority, void *arg)
+{
+	struct wrtbuf *wbuf = arg;
+
+	wrtbuf_write(wbuf, key, strlen(key));
+	wrtbuf_write(wbuf, " ", 1);
+	wrtbuf_write(wbuf, str, len - 1);
+	wrtbuf_write(wbuf, "\n", 1);
+}
+
+void index_dump(struct index_file *in, int fd, bool alias_prefix)
+{
+	struct wrtbuf wbuf;
+
+	wrtbuf_init(&wbuf, fd);
+	index_walk(in, alias_prefix, index_dump_cb, &wbuf);
 	wrtbuf_flush(&wbuf);
 }
 
@@ -852,22 +868,21 @@
 	return NULL;
 }
 
-static void index_mm_dump_node(struct index_mm_node *node, struct strbuf *buf,
-			       struct wrtbuf *wbuf)
+static void index_mm_walk_node(const struct index_mm_node *node, struct strbuf *buf,
+			       index_walk_cb *callback, void *arg)
 {
 	const void *p;
 	size_t i, pushed;
+	const char *key;
 
 	pushed = strbuf_pushchars(buf, node->prefix);
+	key = strbuf_str(buf);
 
 	for (i = 0, p = node->values; i < node->value_count; i++) {
 		struct index_mm_value v;
 
 		read_value_mm(&p, &v);
-		wrtbuf_write(wbuf, buf->bytes, strbuf_used(buf));
-		wrtbuf_write(wbuf, " ", 1);
-		wrtbuf_write(wbuf, v.value, v.len);
-		wrtbuf_write(wbuf, "\n", 1);
+		callback(key, v.value, v.len, v.priority, arg);
 	}
 
 	for (uint8_t ch = node->first; ch <= node->last; ch++) {
@@ -878,27 +893,34 @@
 			continue;
 
 		if (strbuf_pushchar(buf, ch)) {
-			index_mm_dump_node(child, buf, wbuf);
+			index_mm_walk_node(child, buf, callback, arg);
 			strbuf_popchar(buf);
 		}
 	}
 
 	strbuf_popchars(buf, pushed);
 }
 
-void index_mm_dump(const struct index_mm *idx, int fd, bool alias_prefix)
+void index_mm_walk(const struct index_mm *idx, bool alias_prefix, index_walk_cb *callback,
+		   void *arg)
 {
 	DECLARE_STRBUF_WITH_STACK(buf, 128);
 	struct index_mm_node nbuf, *root;
-	struct wrtbuf wbuf;
 
 	root = index_mm_readroot(idx, &nbuf);
 	if (root == NULL)
 		return;
 
-	wrtbuf_init(&wbuf, fd);
 	if (!alias_prefix || strbuf_pushchars(&buf, "alias "))
-		index_mm_dump_node(root, &buf, &wbuf);
+		index_mm_walk_node(root, &buf, callback, arg);
+}
+
+void index_mm_dump(const struct index_mm *idx, int fd, bool alias_prefix)
+{
+	struct wrtbuf wbuf;
+
+	wrtbuf_init(&wbuf, fd);
+	index_mm_walk(idx, alias_prefix, index_dump_cb, &wbuf);
 	wrtbuf_flush(&wbuf);
 }
 

libkmod/libkmod-index.h

@@ -16,10 +16,14 @@ struct index_value {
 
 /* In-memory index (depmod only) */
 struct index_file;
+typedef void(index_walk_cb)(const char *key, const char *value, unsigned int len,
+			    unsigned int prio, void *arg);
 struct index_file *index_file_open(const char *filename);
 void index_file_close(struct index_file *idx);
 char *index_search(struct index_file *idx, const char *key);
 void index_dump(struct index_file *in, int fd, bool alias_prefix);
+void index_walk(struct index_file *in, bool alias_prefix, index_walk_cb *callback,
+		void *arg);
 struct index_value *index_searchwild(struct index_file *idx, const char *key);
 
 void index_values_free(struct index_value *values);
@@ -31,4 +35,6 @@ int index_mm_open(const struct kmod_ctx *ctx, const char *filename,
 void index_mm_close(struct index_mm *index);
 char *index_mm_search(const struct index_mm *idx, const char *key);
 struct index_value *index_mm_searchwild(const struct index_mm *idx, const char *key);
+void index_mm_walk(const struct index_mm *idx, bool alias_prefix, index_walk_cb *callback,
+		   void *arg);
 void index_mm_dump(const struct index_mm *idx, int fd, bool alias_prefix);

libkmod/libkmod-internal.h

@@ -133,6 +133,7 @@ _nonnull_(1)void kmod_module_set_visited(struct kmod_module *mod, bool visited);
 _nonnull_(1) void kmod_module_set_builtin(struct kmod_module *mod, bool builtin);
 _nonnull_(1) void kmod_module_set_required(struct kmod_module *mod, bool required);
 _nonnull_all_ bool kmod_module_is_builtin(struct kmod_module *mod);
+_nonnull_(1, 2) struct kmod_list *kmod_module_info_append(struct kmod_list **list, const char *key, size_t keylen, const char *value, size_t valuelen);
 
 /* libkmod-file.c */
 struct kmod_file;

libkmod/libkmod-module.c

@@ -1777,9 +1777,9 @@ static void kmod_module_info_free(struct kmod_module_info *info)
 	free(info);
 }
 
-static struct kmod_list *kmod_module_info_append(struct kmod_list **list, const char *key,
-						 size_t keylen, const char *value,
-						 size_t valuelen)
+struct kmod_list *kmod_module_info_append(struct kmod_list **list, const char *key,
+					  size_t keylen, const char *value,
+					  size_t valuelen)
 {
 	struct kmod_module_info *info;
 	struct kmod_list *n;

libkmod/libkmod.c

@@ -348,11 +348,13 @@
 	hash_del(ctx->modules_by_name, key);
 }
 
-static int kmod_lookup_alias_from_alias_bin(struct kmod_ctx *ctx,
-					    enum kmod_index index_number,
-					    const char *name, struct kmod_list **list)
+static int kmod_lookup_alias_from_alias_bin_n(struct kmod_ctx *ctx,
+					      enum kmod_index index_number,
+					      const char *name, struct kmod_list **list,
+					      unsigned int max_match)
 {
 	int err, nmatch = 0;
+	unsigned int n;
 	struct index_file *idx;
 	struct index_value *realnames, *realname;
 
@@ -378,7 +380,8 @@
 		index_file_close(idx);
 	}
 
-	for (realname = realnames; realname; realname = realname->next) {
+	for (realname = realnames, n = 0; realname && n < max_match;
+	     realname = realname->next, n++) {
 		struct kmod_module *mod;
 		struct kmod_list *node;
 
@@ -409,14 +412,21 @@
 	return err;
 }
 
+static int kmod_lookup_alias_from_alias_bin(struct kmod_ctx *ctx,
+					    enum kmod_index index_number,
+					    const char *name, struct kmod_list **list)
+{
+	return kmod_lookup_alias_from_alias_bin_n(ctx, index_number, name, list, UINT_MAX);
+}
+
 int kmod_lookup_alias_from_symbols_file(struct kmod_ctx *ctx, const char *name,
 					struct kmod_list **list)
 {
 	if (!strstartswith(name, "symbol:"))
 		return 0;
 
-	return kmod_lookup_alias_from_alias_bin(ctx, KMOD_INDEX_MODULES_SYMBOL, name,
-						list);
+	return kmod_lookup_alias_from_alias_bin_n(ctx, KMOD_INDEX_MODULES_SYMBOL, name,
+						  list, 1);
 }
 
 int kmod_lookup_alias_from_aliases_file(struct kmod_ctx *ctx, const char *name,

man/depmod.8.scd

@@ -7,10 +7,10 @@ depmod - Generate modules.dep and map files.
 # SYNOPSIS
 
 *depmod* [*-b* _basedir_] [*-m* _moduledir_] [*-o* _outdir_] [*-e*] [*-E* _Module.symvers_]
-\ \ \ \ \ \ \ \[*-F* _System.map_] [*-n*] [*-v*] [*-A*] [*-P* _prefix_] [*-w*] [_version_]
+\ \ \ \ \ \ \ \[*-F* _System.map_] [*-n*] [*-v*] [*-A*] [*-P* _prefix_] [*-w*] [*-x*] [*-I*] [_version_]
 
 *depmod* [*-e*] [*-E* _Module.symvers_] [*-F* _System.map_] [*-n*] [*-v*] [*-P* _prefix_]
-\ \ \ \ \ \ \ \[*-w*] [_version_] [_filename_...]
+\ \ \ \ \ \ \ \[*-w*] [*-x*] [*-I*] [_version_] [_filename_...]
 
 # DESCRIPTION
 
@@ -25,7 +25,7 @@ and <BASEDIR> is empty. See options below to override when needed. It determines
 what symbols each module exports and needs.  This list is written to
 *modules.dep*, and a binary hashed version named modules.dep.bin, in the same
 directory. If filenames are given on the command line, only those modules are
-examined (which is rarely useful unless all modules are listed). *depmod* also
+examined (which is rarely useful unless incremental mode is used). *depmod* also
 creates a list of symbols provided by modules in the file named modules.symbols
 and its binary hashed version, modules.symbols.bin. Finally, *depmod* will
 output a file named modules.devname if modules supply special device names
@@ -136,6 +136,13 @@ depmod -b /tmp/build -m kernel-modules
 *-h*, *--help*
 	Print the help message and exit.
 
+*-I*, *--incremental*
+	Run in incremental mode. This mode preserves previous module dependencies
+	and adds the dependencies of the modules given on the command line. If no
+	modules are given or *--all* is set, the module directory is scanned for
+	added or deleted modules, and the *modules.dep* file and other outputs
+	are updated accordingly.
+
 *-n*, *--show*, *--dry-run*
 	This sends the resulting *modules.dep* and the various map files to
 	standard output rather than writing them into the module directory.
@@ -155,6 +162,12 @@ depmod -b /tmp/build -m kernel-modules
 *-w*
 	Warn on duplicate dependencies, aliases, symbol versions, etc.
 
+*-x*, *--errexit*
+	Exit with an error status if any condition occurs that would create
+	a warning with *-e*, i.e. if some module requires an unknown symbol,
+	or if a symbol with a symbol version that doesn't match the version
+	provided by the kernel or other modules.
+
 # COPYRIGHT
 
 This manual page originally Copyright 2002, Rusty Russell, IBM Corporation.

scripts/setup-modules.sh

@@ -13,4 +13,4 @@ if test "$SRCDIR" != "$BUILDDIR"; then
 fi
 
 export MAKEFLAGS=${MAKEFLAGS-"-j$(nproc)"}
-"${MAKE-make}" -C "$PWD/$MODULE_PLAYGROUND" modules
+"${MAKE-make}" -C "$PWD/$MODULE_PLAYGROUND"