[PATCH] BLK_DEV_INITRD: do not require BLK_DEV_RAM=y

Initramfs initrd images do not need a ramdisk device, so remove this
restriction in Kconfig.  BLK_DEV_RAM=n saves about 13k on i386.  Also
without ramdisk device there's no need for "dry run", so initramfs unpacks
much faster.

People using cramfs, squashfs, or gzipped ext2/minix initrd images are
probably smart enough not to turn off ramdisk support by accident.

Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 10 insertions, 1 deletions

diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index 8b1331677407..e57ac5a43246 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -401,7 +401,6 @@ config BLK_DEV_RAM_SIZE
 
 config BLK_DEV_INITRD
         bool "Initial RAM disk (initrd) support"
-        depends on BLK_DEV_RAM=y
         help
           The initial RAM disk is a RAM disk that is loaded by the boot loader
           (loadlin or lilo) and that is mounted as root before the normal boot
diff --git a/init/initramfs.c b/init/initramfs.c
index 637344b05981..77b934cccefe 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -506,6 +506,7 @@ void __init populate_rootfs(void)
                 panic(err);
 #ifdef CONFIG_BLK_DEV_INITRD
         if (initrd_start) {
+#ifdef CONFIG_BLK_DEV_RAM
                 int fd;
                 printk(KERN_INFO "checking if image is initramfs...");
                 err = unpack_to_rootfs((char *)initrd_start,
@@ -525,6 +526,15 @@ void __init populate_rootfs(void)
                         sys_close(fd);
                         free_initrd();
                 }
+#else
+                printk(KERN_INFO "Unpacking initramfs...");
+                err = unpack_to_rootfs((char *)initrd_start,
+                        initrd_end - initrd_start, 0);
+                if (err)
+                        panic(err);
+                printk(" done\n");
+                free_initrd();
+#endif
         }
 #endif
 }