SOURCES (LINUX_2_6): kernel-inittmpfs.patch (NEW) - raw http://ftp...

[zbyniu]

Author: zbyniu                       Date: Wed Mar 12 01:52:06 2008 GMT
Module: SOURCES                       Tag: LINUX_2_6
---- Log message:
- raw http://ftp.leg.uct.ac.za/pub/linux/rip/inittmpfs-2.6.14.diff.gz

---- Files affected:
SOURCES:
   kernel-inittmpfs.patch (NONE -> 1.1.2.1)  (NEW)

---- Diffs:

================================================================
Index: SOURCES/kernel-inittmpfs.patch
diff -u /dev/null SOURCES/kernel-inittmpfs.patch:1.1.2.1
--- /dev/null	Wed Mar 12 02:52:06 2008
+++ SOURCES/kernel-inittmpfs.patch	Wed Mar 12 02:52:00 2008
@@ -0,0 +1,134 @@
+diff -ur linux-2.6.14.orig/fs/Kconfig linux-2.6.14/fs/Kconfig
+--- linux-2.6.14.orig/fs/Kconfig	2005-09-11 03:19:07.000000000 +0000
++++ linux-2.6.14/fs/Kconfig	2005-09-11 03:19:42.000000000 +0000
+@@ -805,6 +805,18 @@
+ 
+ 	  See <file:Documentation/filesystems/tmpfs.txt> for details.
+ 
++config EARLYUSERSPACE_ON_TMPFS
++	bool "Unpack the early userspace onto tmpfs"
++	depends TMPFS
++	default y
++	help
++	  Use this to have your early userspace placed (decompressed)
++	  onto tmpfs as opposed ramfs. This will allow you to
++	  restrict the size of your root-filesystem and it will also
++	  be swappable.
++   
++	  If unsure, say Y.
++
+ config HUGETLBFS
+ 	bool "HugeTLB file system support"
+ 	depends X86 || IA64 || PPC64 || SPARC64 || SUPERH || X86_64 || BROKEN
+Only in linux-2.6.14/fs: Kconfig.orig
+diff -ur linux-2.6.14.orig/init/initramfs.c linux-2.6.14/init/initramfs.c
+--- linux-2.6.14.orig/init/initramfs.c	2005-08-28 23:41:01.000000000 +0000
++++ linux-2.6.14/init/initramfs.c	2005-09-11 03:19:42.000000000 +0000
+@@ -6,6 +6,7 @@
+ #include <linux/delay.h>
+ #include <linux/string.h>
+ #include <linux/syscalls.h>
++#include <asm/uaccess.h>
+ 
+ static __initdata char *message;
+ static void __init error(char *x)
+@@ -463,6 +464,49 @@
+ 	return message;
+ }
+ 
++/* If we want the rootfs on initramfs so we mount initramfs over the
++ * rootfs before we unpack it. The little dance we do by creating a
++ * pivot point and moving the root to that is in fact necessary
++ * because lookups of "." don't resolve mountpoints.
++ */
++static inline void __init overmount_rootfs(void)
++   {
++#ifdef CONFIG_EARLYUSERSPACE_ON_TMPFS
++    int init_tmpfs(void);
++    int (*initfunc)(void) = init_tmpfs;
++    mm_segment_t oldfs;
++    char pivot[] = "/pivot";
++   
++    /* Explicitly go and init the overmount fs early (long-term
++     * the need for this will probably go away. */
++   
++    if (initfunc())
++    goto err;
++   
++    oldfs = get_fs();
++    set_fs(KERNEL_DS);
++   
++    if (sys_mkdir(pivot, 0700) < 0)
++    goto err;
++    if (sys_mount("tmpfs", pivot, "tmpfs", 0, "size=95%"))
++    goto err;
++   
++    /* Below here errors are unlikely and icky to deal with. */
++    sys_chdir(pivot);
++    sys_mount(".", "/", NULL, MS_MOVE, NULL);
++    sys_chdir(".");
++    sys_chroot(".");
++    printk(KERN_INFO "Overmounted tmpfs\n");
++    goto out;
++   
++    err:
++    printk(KERN_ERR "Overmount error\n");
++   
++    out:
++    set_fs(oldfs);
++#endif /* CONFIG_EARLYUSERSPACE_ON_TMPFS */
++}
++
+ extern char __initramfs_start[], __initramfs_end[];
+ #ifdef CONFIG_BLK_DEV_INITRD
+ #include <linux/initrd.h>
+@@ -482,6 +526,9 @@
+ 			initrd_end - initrd_start, 1);
+ 		if (!err) {
+ 			printk(" it is\n");
++#ifdef CONFIG_EARLYUSERSPACE_ON_TMPFS
++                        overmount_rootfs();
++#endif /* CONFIG_EARLYUSERSPACE_ON_TMPFS */
+ 			unpack_to_rootfs((char *)initrd_start,
+ 				initrd_end - initrd_start, 0);
+ 			free_initrd_mem(initrd_start, initrd_end);
+diff -ur linux-2.6.14.orig/init/main.c linux-2.6.14/init/main.c
+--- linux-2.6.14.orig/init/main.c	2005-09-11 03:19:07.000000000 +0000
++++ linux-2.6.14/init/main.c	2005-09-11 03:22:43.000000000 +0000
+@@ -701,6 +701,11 @@
+ 	if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
+ 		ramdisk_execute_command = NULL;
+ 		prepare_namespace();
++#ifdef CONFIG_EARLYUSERSPACE_ON_TMPFS
++                int init_tmpfs(void);
++                int (*initfunc)(void) = init_tmpfs;
++                initfunc();
++#endif /* CONFIG_EARLYUSERSPACE_ON_TMPFS */
+ 	}
+ 
+ 	/*
+diff -ur linux-2.6.14.orig/mm/shmem.c linux-2.6.14/mm/shmem.c
+--- linux-2.6.14.orig/mm/shmem.c	2005-09-11 03:19:07.000000000 +0000
++++ linux-2.6.14/mm/shmem.c	2005-09-11 03:19:42.000000000 +0000
+@@ -2136,7 +2136,7 @@
+ };
+ static struct vfsmount *shm_mnt;
+ 
+-static int __init init_tmpfs(void)
++int __init init_tmpfs(void)
+ {
+ 	int error;
+ 
+@@ -2169,7 +2169,12 @@
+ 	shm_mnt = ERR_PTR(error);
+ 	return error;
+ }
++/* Don't do this if we are calling it early explicity */
++#ifndef CONFIG_EARLYUSERSPACE_ON_TMPFS
++/* If CONFIG_EARLYUSERSPACE_ON_TMPFS is set then we will interpose
++ * ramfs so this will get called explicitly and early */
+ module_init(init_tmpfs)
++#endif /* !CONFIG_EARLYUSERSPACE_ON_TMPFS */
+ 
+ /*
+  * shmem_file_setup - get an unlinked file living in tmpfs
================================================================