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Add a filesystem option so a device can be booted over NFS.

PATCH New Sagaert Johan 4 participants 6 messages Jul 15, 2014

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Sagaert Johan

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#0 lore raw

PATCH 1/1 Add a filesystem option so a device can be booted over NFS.

This options allows specifying a directory where the target rootfs is copied to so it can be used to boot a device over NFS.

Signed-off-by Sagaert Johan <[email protected]>
---
 Makefile         |  5 +++++
 fs/Config.in     |  1 +
 fs/nfs/Config.in | 13 +++++++++++++
 fs/nfs/nfs.mk    | 16 ++++++++++++++++
 4 files changed, 35 insertions(+)
 create mode 100644 fs/nfs/Config.in
 create mode 100644 fs/nfs/nfs.mk
Makefile +5 -0
index dcbf2b3..4c7a707 100644
@@ -833,6 +833,11 @@ clean:
 	rm -rf $(TARGET_DIR) $(BINARIES_DIR) $(HOST_DIR) \
 		$(BUILD_DIR) $(BASE_DIR)/staging \
 		$(LEGAL_INFO_DIR)
+ifeq ($(BR2_TARGET_ROOTFS_NFS),y)
+		if [ -d $(TARGET_ROOTFS_NFS_PATH) ]; then \
+			rm -rf $(TARGET_ROOTFS_NFS_PATH) ;\
+		fi
+endif
 
 distclean: clean
 ifeq ($(DL_DIR),$(TOPDIR)/dl)
fs/Config.in +1 -0
index 5853113..aa1460b 100644
@@ -7,6 +7,7 @@ source "fs/ext2/Config.in"
 source "fs/initramfs/Config.in"
 source "fs/iso9660/Config.in"
 source "fs/jffs2/Config.in"
+source "fs/nfs/Config.in"
 source "fs/romfs/Config.in"
 source "fs/squashfs/Config.in"
 source "fs/tar/Config.in"
fs/nfs/Config.in new file +13 -0
new file mode 100644
index 0000000..cf32619
@@ -0,0 +1,13 @@
+config BR2_TARGET_ROOTFS_NFS
+	bool "create NFS boot directory"
+	help
+	  Creates a directory that contains the rootfs for booting over NFS.
+
+if BR2_TARGET_ROOTFS_NFS
+config BR2_TARGET_ROOTFS_NFS_PATH
+	string "path to the directory used for booting over NFS"
+	default "~/nfsrootfs"
+	help
+	  Path to the directory used for booting over NFS.
+	  (This should also be added to your /etc/exports file.)
+endif
fs/nfs/nfs.mk new file +15 -0
new file mode 100644
index 0000000..003ce71
@@ -0,0 +1,15 @@
+################################################################################
+#
+# create a directory for booting the device from an NFS.
+#
+################################################################################
+
+TARGET_ROOTFS_NFS_PATH := $(call qstrip,$(BR2_TARGET_ROOTFS_NFS_PATH))
+
+define ROOTFS_NFS_CMD
+	rm -rf $(TARGET_ROOTFS_NFS_PATH) ;\
+	mkdir -p  $(TARGET_ROOTFS_NFS_PATH) ;\
+	cp -r $(TARGET_DIR)/* $(TARGET_ROOTFS_NFS_PATH)
+endef
+
+$(eval $(call ROOTFS_TARGET,nfs))
Signature · 1 line
2.0.1
#1 lore raw

PATCH 1/1 Add a filesystem option so a device can be booted over NFS.

Hi Sagaert,

Quoted 18 lines · Sagaert Johan

This options allows specifying a directory where the target rootfs is copied to so it can be used to boot a device over NFS.

Signed-off-by Sagaert Johan <[email protected]>
---
 Makefile         |  5 +++++
 fs/Config.in     |  1 +
 fs/nfs/Config.in | 13 +++++++++++++
 fs/nfs/nfs.mk    | 16 ++++++++++++++++
 4 files changed, 35 insertions(+)
 create mode 100644 fs/nfs/Config.in
 create mode 100644 fs/nfs/nfs.mk
Makefile +0 -0
index dcbf2b3..4c7a707 100644

Makefile clean: · line 839

Quoted 7 lines
Makefile +4 -0
@@ -833,6 +833,11 @@ clean:
 	rm -rf $(TARGET_DIR) $(BINARIES_DIR) $(HOST_DIR) \
 		$(BUILD_DIR) $(BASE_DIR)/staging \
 		$(LEGAL_INFO_DIR)
+ifeq ($(BR2_TARGET_ROOTFS_NFS),y)
+		if [ -d $(TARGET_ROOTFS_NFS_PATH) ]; then \
+			rm -rf $(TARGET_ROOTFS_NFS_PATH) ;\
+		fi

Too many indentation tabs here.

Quoted 43 lines
Makefile +1 -0
+endif
 
 distclean: clean
 ifeq ($(DL_DIR),$(TOPDIR)/dl)
fs/Config.in +1 -0
index 5853113..aa1460b 100644
@@ -7,6 +7,7 @@ source "fs/ext2/Config.in"
 source "fs/initramfs/Config.in"
 source "fs/iso9660/Config.in"
 source "fs/jffs2/Config.in"
+source "fs/nfs/Config.in"
 source "fs/romfs/Config.in"
 source "fs/squashfs/Config.in"
 source "fs/tar/Config.in"
fs/nfs/Config.in new file +13 -0
new file mode 100644
index 0000000..cf32619
@@ -0,0 +1,13 @@
+config BR2_TARGET_ROOTFS_NFS
+	bool "create NFS boot directory"
+	help
+	  Creates a directory that contains the rootfs for booting over NFS.
+
+if BR2_TARGET_ROOTFS_NFS
+config BR2_TARGET_ROOTFS_NFS_PATH
+	string "path to the directory used for booting over NFS"
+	default "~/nfsrootfs"
+	help
+	  Path to the directory used for booting over NFS.
+	  (This should also be added to your /etc/exports file.)
+endif
fs/nfs/nfs.mk new file +2 -0
new file mode 100644
index 0000000..003ce71
@@ -0,0 +1,15 @@
+################################################################################
+#

fs/nfs/nfs.mk line 12

Quoted 10 lines
fs/nfs/nfs.mk new file +10 -0
+# create a directory for booting the device from an NFS.
+#
+################################################################################
+
+TARGET_ROOTFS_NFS_PATH := $(call qstrip,$(BR2_TARGET_ROOTFS_NFS_PATH))
+
+define ROOTFS_NFS_CMD
+	rm -rf $(TARGET_ROOTFS_NFS_PATH) ;\
+	mkdir -p  $(TARGET_ROOTFS_NFS_PATH) ;\
+	cp -r $(TARGET_DIR)/* $(TARGET_ROOTFS_NFS_PATH)

This doesn't look right. What about creating device nodes and SUID binaries? You must be root for that, $(TARGET_DIR) doesn't carry this information (fakeroot does that), and even if it did cp doesn't preserve these attributes. A better approach would be to extract a generated tar image, but you still must be root for that.

baruch

Quoted 3 lines
fs/nfs/nfs.mk new file +3 -0
+endef
+
+$(eval $(call ROOTFS_TARGET,nfs))
Signature · 3 lines
     http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
   - baruch at tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -
#2 lore raw

PATCH 1/1 Add a filesystem option so a device can be booted over NFS.

In reply to Sagaert Johan

fs/nfs/nfs.mk line 15

Quoted 7 lines · Sagaert Johan
fs/nfs/nfs.mk new file +7 -0
+define ROOTFS_NFS_CMD
+       rm -rf $(TARGET_ROOTFS_NFS_PATH) ;\
+       mkdir -p  $(TARGET_ROOTFS_NFS_PATH) ;\
+       cp -r $(TARGET_DIR)/* $(TARGET_ROOTFS_NFS_PATH)
+endef
+
+$(eval $(call ROOTFS_TARGET,nfs))

As Baruch suggested, using "cp" for this purpose is no good. Refer to the buildroot manual and the warning file installed to the target dir:

http://buildroot.uclibc.org/downloads/manual/manual.html#_nfs_boot
http://git.buildroot.net/buildroot/tree/support/misc/target-dir-warning.txt

Instead, consider simply making a post-build script that does the un-tar for you. Maybe something like this:

    #!/bin/sh

    NFSROOT=${NFS_SHARE:-/srv/my_nfsroot}

    mkdir -p $NFS_SHARE
    sudo tar -xavf ${BASE_DIR}/images.rootfs.tar -C $NFSROOT

(Not actually tested.)

Then no patch is needed.

Danomi -

#3 lore raw

PATCH 1/1 Add a filesystem option so a device can be booted over NFS.

Quoted 9 lines · Danomi Manchego

Instead, consider simply making a post-build script that does the un-tar for you. Maybe something like this:

    #!/bin/sh

    NFSROOT=${NFS_SHARE:-/srv/my_nfsroot}

    mkdir -p $NFS_SHARE
    sudo tar -xavf ${BASE_DIR}/images.rootfs.tar -C $NFSROOT

Apologies - those two "NFS_SHARE" should have been "NFSROOT" - last minute name change ...
Danomi -

author
#4 lore raw

PATCH 1/1 Add a filesystem option so a device can be booted over NFS.

In reply to Danomi Manchego

-----Oorspronkelijk bericht-----
Van: Danomi Manchego [mailto:danomimanchego123 at gmail.com]
Verzonden: dinsdag 15 juli 2014 16:46
Aan: Sagaert Johan
CC: buildroot
Onderwerp: Re: [Buildroot] [PATCH 1/1] Add a filesystem option so a device can be booted over NFS.

fs/nfs/nfs.mk line 15

Quoted 6 lines · Sagaert Johan
fs/nfs/nfs.mk new file +6 -0
+define ROOTFS_NFS_CMD
+       rm -rf $(TARGET_ROOTFS_NFS_PATH) ;\
+       mkdir -p  $(TARGET_ROOTFS_NFS_PATH) ;\
+       cp -r $(TARGET_DIR)/* $(TARGET_ROOTFS_NFS_PATH) endef
+
+$(eval $(call ROOTFS_TARGET,nfs))

As Baruch suggested, using "cp" for this purpose is no good. Refer to the buildroot manual and the warning file installed to the target dir:

http://buildroot.uclibc.org/downloads/manual/manual.html#_nfs_boot
http://git.buildroot.net/buildroot/tree/support/misc/target-dir-warning.txt

Quoted 9 lines

Instead, consider simply making a post-build script that does the un-tar for you. Maybe something like this:

   #!/bin/sh

   NFSROOT=${NFS_SHARE:-/srv/my_nfsroot}

   mkdir -p $NFS_SHARE
   sudo tar -xavf ${BASE_DIR}/images.rootfs.tar -C $NFSROOT
Quoted 4 lines

(Not actually tested.)

Then no patch is needed.
Danomi -

Hi all

Right, until now I always used a post script that extracted the rootfs.tar. So I tought I could integrate this into br.

And yes, I run linux in a vm and am to lazy to create a user and use sudo, so on my virtual linux machine, I am always logged in as root.

Regards, Johan

#5 lore raw

PATCH 1/1 Add a filesystem option so a device can be booted over NFS.

In reply to Sagaert Johan

Dear Sagaert Johan,

Quoted 5 lines · Sagaert Johan

This options allows specifying a directory where the target rootfs is copied to so it can be used to boot a device over NFS.

Signed-off-by Sagaert Johan <[email protected]>

How to boot from NFS is explained at
http://buildroot.org/downloads/manual/manual.html#_nfs_boot, and the solution you propose requires root privileges to extract the tarball image, which is not acceptable as Buildroot doesn't run as root.

Therefore, I'll have to mark your patch as Rejected in our patch tracking system. Do not hesitate to let us know if you disagree and see a better way of doing things.

Thanks,

Thomas

Signature · 3 lines
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com