clean up atags exporting code

This gets rid of two static variables (one of them being __initdata)
and a static function.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Acked-by: Uli Luckas <u.luckas@road.de>

1 files changed, 39 insertions, 41 deletions

diff --git a/arch/arm/kernel/atags.c b/arch/arm/kernel/atags.c
index 56fef9a05504..42a1a1415fa6 100644
--- a/arch/arm/kernel/atags.c
+++ b/arch/arm/kernel/atags.c
@@ -6,9 +6,8 @@
 
 struct buffer {
         size_t size;
-        char *data;
+        char data[];
 };
-static struct buffer tags_buffer;
 
 static int
 read_buffer(char* page, char** start, off_t off, int count,
@@ -28,58 +27,57 @@ read_buffer(char* page, char** start, off_t off, int count,
         return count;
 }
 
-
-static int
-create_proc_entries(void)
-{
-        struct proc_dir_entry* tags_entry;
-
-        tags_entry = create_proc_read_entry("atags", 0400, NULL, read_buffer, &tags_buffer);
-        if (!tags_entry)
-                return -ENOMEM;
-
-        return 0;
-}
-
 #define BOOT_PARAMS_SIZE 1536
-static char __initdata atags_copy_buf[BOOT_PARAMS_SIZE];
-static char __initdata *atags_copy;
+static char __initdata atags_copy[BOOT_PARAMS_SIZE];
 
 void __init save_atags(const struct tag *tags)
 {
-        atags_copy = atags_copy_buf;
-        memcpy(atags_copy, tags, sizeof(atags_copy_buf));
+        memcpy(atags_copy, tags, sizeof(atags_copy));
 }
 
-
 static int __init init_atags_procfs(void)
 {
-        struct tag *tag;
-        int error;
+        /*
+         * This cannot go into save_atags() because kmalloc and proc don't work
+         * yet when it is called.
+         */
+        struct proc_dir_entry *tags_entry;
+        struct tag *tag = (struct tag *)atags_copy;
+        struct buffer *b;
+        size_t size;
 
-        if (!atags_copy) {
-                printk(KERN_WARNING "Exporting ATAGs: No saved tags found\n");
-                return -EIO;
+        if (tag->hdr.tag != ATAG_CORE) {
+                printk(KERN_INFO "No ATAGs?");
+                return -EINVAL;
         }
 
-        for (tag = (struct tag *) atags_copy; tag->hdr.size; tag = tag_next(tag))
+        for (; tag->hdr.size; tag = tag_next(tag))
                 ;
 
-        tags_buffer.size = ((char *) tag - atags_copy) + sizeof(tag->hdr);
-        tags_buffer.data = kmalloc(tags_buffer.size, GFP_KERNEL);
-        if (tags_buffer.data == NULL)
-                return -ENOMEM;
-        memcpy(tags_buffer.data, atags_copy, tags_buffer.size);
-
-        error = create_proc_entries();
-        if (error) {
-                printk(KERN_ERR "Exporting ATAGs: not enough memory\n");
-                kfree(tags_buffer.data);
-                tags_buffer.size = 0;
-                tags_buffer.data = NULL;
-        }
+        /* include the terminating ATAG_NONE */
+        size = (char *)tag - atags_copy + sizeof(struct tag_header);
 
-        return error;
-}
+        WARN_ON(tag->hdr.tag != ATAG_NONE);
+
+        b = kmalloc(sizeof(*b) + size, GFP_KERNEL);
+        if (!b)
+                goto nomem;
 
+        b->size = size;
+        memcpy(b->data, atags_copy, size);
+
+        tags_entry = create_proc_read_entry("atags", 0400,
+                        NULL, read_buffer, b);
+
+        if (!tags_entry)
+                goto nomem;
+
+        return 0;
+
+nomem:
+        kfree(b);
+        printk(KERN_ERR "Exporting ATAGs: not enough memory\n");
+
+        return -ENOMEM;
+}
 arch_initcall(init_atags_procfs);