diff options
| -rw-r--r-- | MAINTAINERS | 1 | ||||
| -rw-r--r-- | fs/proc/Makefile | 1 | ||||
| -rw-r--r-- | fs/proc/bootconfig.c | 89 |
3 files changed, 91 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 06005006de7c..903e8a7ed0bf 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15774,6 +15774,7 @@ EXTRA BOOT CONFIG M: Masami Hiramatsu <mhiramat@kernel.org> S: Maintained F: lib/bootconfig.c +F: fs/proc/bootconfig.c F: include/linux/bootconfig.h F: tools/bootconfig/* diff --git a/fs/proc/Makefile b/fs/proc/Makefile index ead487e80510..bd08616ed8ba 100644 --- a/fs/proc/Makefile +++ b/fs/proc/Makefile @@ -33,3 +33,4 @@ proc-$(CONFIG_PROC_KCORE) += kcore.o proc-$(CONFIG_PROC_VMCORE) += vmcore.o proc-$(CONFIG_PRINTK) += kmsg.o proc-$(CONFIG_PROC_PAGE_MONITOR) += page.o +proc-$(CONFIG_BOOT_CONFIG) += bootconfig.o diff --git a/fs/proc/bootconfig.c b/fs/proc/bootconfig.c new file mode 100644 index 000000000000..9955d75c0585 --- /dev/null +++ b/fs/proc/bootconfig.c @@ -0,0 +1,89 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * /proc/bootconfig - Extra boot configuration + */ +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/printk.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/bootconfig.h> +#include <linux/slab.h> + +static char *saved_boot_config; + +static int boot_config_proc_show(struct seq_file *m, void *v) +{ + if (saved_boot_config) + seq_puts(m, saved_boot_config); + return 0; +} + +/* Rest size of buffer */ +#define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) + +/* Return the needed total length if @size is 0 */ +static int __init copy_xbc_key_value_list(char *dst, size_t size) +{ + struct xbc_node *leaf, *vnode; + const char *val; + char *key, *end = dst + size; + int ret = 0; + + key = kzalloc(XBC_KEYLEN_MAX, GFP_KERNEL); + + xbc_for_each_key_value(leaf, val) { + ret = xbc_node_compose_key(leaf, key, XBC_KEYLEN_MAX); + if (ret < 0) + break; + ret = snprintf(dst, rest(dst, end), "%s = ", key); + if (ret < 0) + break; + dst += ret; + vnode = xbc_node_get_child(leaf); + if (vnode && xbc_node_is_array(vnode)) { + xbc_array_for_each_value(vnode, val) { + ret = snprintf(dst, rest(dst, end), "\"%s\"%s", + val, vnode->next ? ", " : "\n"); + if (ret < 0) + goto out; + dst += ret; + } + } else { + ret = snprintf(dst, rest(dst, end), "\"%s\"\n", val); + if (ret < 0) + break; + dst += ret; + } + } +out: + kfree(key); + + return ret < 0 ? ret : dst - (end - size); +} + +static int __init proc_boot_config_init(void) +{ + int len; + + len = copy_xbc_key_value_list(NULL, 0); + if (len < 0) + return len; + + if (len > 0) { + saved_boot_config = kzalloc(len + 1, GFP_KERNEL); + if (!saved_boot_config) + return -ENOMEM; + + len = copy_xbc_key_value_list(saved_boot_config, len + 1); + if (len < 0) { + kfree(saved_boot_config); + return len; + } + } + + proc_create_single("bootconfig", 0, NULL, boot_config_proc_show); + + return 0; +} +fs_initcall(proc_boot_config_init); |