On Mon, Jan 30, 2023 at 06:33:24PM +0000, Emil Velikov wrote:
From: Emil Velikov <emil.velikov@xxxxxxxxxxxxx>
This option is equivalent to basedir, with the small difference being
that's where the meta-data files are generated. In other words, this
allows us to have read-only input modules and modules.dep, while still
being able to generate the meta-data files.
Signed-off-by: Emil Velikov <emil.velikov@xxxxxxxxxxxxx>
---
Hello team,
Here's a handy feature behind the request at
https://github.com/kmod-project/kmod/issues/13
This is my first time hacking on kmod, so hope I didn't make too many
mistakes :-) There are a few TODO notes below where your input is
greatly appreciated.
TODO:
- Add tests - team, any pointers or requests?
yep, please add one that calls depmod with this new option.
Copy and extend one of the tests in testsuite/test-depmod.c
You will have to prepare a "rootfs" under
testsuite/rootfs-pristine/test-depmod/<name-of-the-test>. Make sure to
add the normal files coming from kernel and checking for the output in
the other directory you passed as argument.
- Split the dirnamelen shorthand tenary operator change - is it worth
it?
---
man/depmod.xml | 19 +++++++++++++++++++
tools/depmod.c | 25 ++++++++++++++++++++++---
2 files changed, 41 insertions(+), 3 deletions(-)
diff --git a/man/depmod.xml b/man/depmod.xml
index ea0be27..c53624d 100644
--- a/man/depmod.xml
+++ b/man/depmod.xml
@@ -45,6 +45,7 @@
<cmdsynopsis>
<command>depmod</command>
<arg><option>-b <replaceable>basedir</replaceable></option></arg>
+ <arg><option>-o <replaceable>outdir</replaceable></option></arg>
<arg><option>-e</option></arg>
<arg><option>-E <replaceable>Module.symvers</replaceable></option></arg>
<arg><option>-F <replaceable>System.map</replaceable></option></arg>
@@ -151,6 +152,24 @@
</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term>
+ <option>-o <replaceable>outdir</replaceable></option>
+ </term>
+ <term>
+ <option>--outdir <replaceable>outdir</replaceable></option>
+ </term>
+ <listitem>
+ <para>
+ If your modules are stored in a read-only location, you may want to
+ create the output meta-data files in another location. Setting
that is probably not the only use case, I'd rephrase with something
like:
Set the output directory where depmod will store any generated file.
<replaceable>outdir</replaceable> serves as a root to that location,
similar to how <replaceable>basedir</replaceable> is used. Also this
setting takes precedence and if used together with
<replaceable>basedir</replaceable> it will result in the input being
that directory, but the output being the one set by
<replaceable>outdir</replaceable>.
+ <replaceable>outdir</replaceable> serves as a root to that location
+ similar to how we use <replaceable>basedir</replaceable>. Use this
+ option if you are a distribution vendor who needs to pre-generate
+ the meta-data files rather than running depmod again later.
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term>
<option>-C</option>
diff --git a/tools/depmod.c b/tools/depmod.c
index 364b7d4..aaf2327 100644
--- a/tools/depmod.c
+++ b/tools/depmod.c
@@ -58,11 +58,12 @@ static const char *default_cfg_paths[] = {
NULL
};
-static const char cmdopts_s[] = "aAb:C:E:F:euqrvnP:wmVh";
+static const char cmdopts_s[] = "aAb:o:C:E:F:euqrvnP:wmVh";
static const struct option cmdopts[] = {
{ "all", no_argument, 0, 'a' },
{ "quick", no_argument, 0, 'A' },
{ "basedir", required_argument, 0, 'b' },
+ { "outdir", required_argument, 0, 'o' },
{ "config", required_argument, 0, 'C' },
{ "symvers", required_argument, 0, 'E' },
{ "filesyms", required_argument, 0, 'F' },
@@ -104,6 +105,7 @@ static void help(void)
"\n"
"The following options are useful for people managing distributions:\n"
"\t-b, --basedir=DIR Use an image of a module tree.\n"
+ "\t-o, --outdir=DIR The output equivalent of basedir.\n"
Output directory for generated files
<basedir> is both input and output, so I don't think the comparison is
good enough.
I think making sure this is working as desired with at least one test
would be good, but overall looks goot to me.
thanks
Lucas De Marchi
"\t-F, --filesyms=FILE Use the file instead of the\n"
"\t current kernel symbols.\n"
"\t-E, --symvers=FILE Use Module.symvers file to check\n"
@@ -467,6 +469,8 @@ struct cfg {
const char *kversion;
char dirname[PATH_MAX];
size_t dirnamelen;
+ char outdirname[PATH_MAX];
+ size_t outdirnamelen;
char sym_prefix;
uint8_t check_symvers;
uint8_t print_unknown;
@@ -2576,7 +2580,7 @@ static int depmod_output(struct depmod *depmod, FILE *out)
{ "modules.devname", output_devname },
{ }
};
- const char *dname = depmod->cfg->dirname;
+ const char *dname = depmod->cfg->outdirname;
int dfd, err = 0;
struct timeval tv;
@@ -2585,6 +2589,11 @@ static int depmod_output(struct depmod *depmod, FILE *out)
if (out != NULL)
dfd = -1;
else {
+ err = mkdir_p(dname, strlen(dname), 0755);
+ if (err < 0) {
+ CRIT("could not create directory %s: %m\n", dname);
+ return err;
+ }
dfd = open(dname, O_RDONLY);
if (dfd < 0) {
err = -errno;
@@ -2898,6 +2907,7 @@ static int do_depmod(int argc, char *argv[])
FILE *out = NULL;
int err = 0, all = 0, maybe_all = 0, n_config_paths = 0;
_cleanup_free_ char *root = NULL;
+ _cleanup_free_ char *out_root = NULL;
_cleanup_free_ const char **config_paths = NULL;
const char *system_map = NULL;
const char *module_symvers = NULL;
@@ -2927,6 +2937,11 @@ static int do_depmod(int argc, char *argv[])
free(root);
root = path_make_absolute_cwd(optarg);
break;
+ case 'o':
+ if (out_root)
+ free(out_root);
+ out_root = path_make_absolute_cwd(optarg);
+ break;
case 'C': {
size_t bytes = sizeof(char *) * (n_config_paths + 2);
void *tmp = realloc(config_paths, bytes);
@@ -3009,7 +3024,11 @@ static int do_depmod(int argc, char *argv[])
cfg.dirnamelen = snprintf(cfg.dirname, PATH_MAX,
"%s/lib/modules/%s",
- root == NULL ? "" : root, cfg.kversion);
+ root ?: "", cfg.kversion);
+
+ cfg.outdirnamelen = snprintf(cfg.outdirname, PATH_MAX,
+ "%s/lib/modules/%s",
+ out_root ?: (root ?: ""), cfg.kversion);
if (optind == argc)
all = 1;
--
2.39.1
