[kernel] Fix 64-bit divide error in btrfs

[Josh Boyer]

commit 7aac3ebb1e0cc675b2cbc54fcc1f98dd73c011b9
Author: Josh Boyer <jwboyer at redhat.com>
Date:   Fri Aug 19 09:30:34 2011 -0400

    Fix 64-bit divide error in btrfs

 btrfs-use-do_div.patch |   38 ++++++++++++++++++++++++++++++++++++++
 kernel.spec            |    7 ++++++-
 2 files changed, 44 insertions(+), 1 deletions(-)
---
diff --git a/btrfs-use-do_div.patch b/btrfs-use-do_div.patch
new file mode 100644
index 0000000..e32907d
--- /dev/null
+++ b/btrfs-use-do_div.patch
@@ -0,0 +1,38 @@
+From: Liu Bo <liubo2009 <at> cn.fujitsu.com>
+Subject: [PATCH] Btrfs: use do_div to avoid compile errors on 32bit box
+Date: 2011-08-19 09:48:44 GMT (3 hours and 36 minutes ago)
+
+When doing div operation of u64 type, we need to be careful and use do_div
+to avoid compile ERROR on 32bit box:
+
+"ERROR: "__udivdi3" [fs/btrfs/btrfs.ko] undefined!
+make[1]: *** [__modpost] Error 1
+
+Signed-off-by: Liu Bo <liubo2009 <at> cn.fujitsu.com>
+---
+ fs/btrfs/extent-tree.c |    4 ++--
+ 1 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
+index 80d6148..9b495ce 100644
+--- a/fs/btrfs/extent-tree.c
++++ b/fs/btrfs/extent-tree.c
+@@ -6796,14 +6796,14 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
+ 	index = get_block_group_index(block_group);
+ 	if (index == 0) {
+ 		dev_min = 4;
+-		min_free /= 2;
++		do_div(min_free, 2);
+ 	} else if (index == 1) {
+ 		dev_min = 2;
+ 	} else if (index == 2) {
+ 		min_free *= 2;
+ 	} else if (index == 3) {
+ 		dev_min = fs_devices->rw_devices;
+-		min_free /= dev_min;
++		do_div(min_free, dev_min);
+ 	}
+
+ 	mutex_lock(&root->fs_info->chunk_mutex);
+-- 
+1.6.5.2
diff --git a/kernel.spec b/kernel.spec
index 873c15f..4d4ed26 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -51,7 +51,7 @@ Summary: The Linux kernel
 # For non-released -rc kernels, this will be prepended with "0.", so
 # for example a 3 here will become 0.3
 #
-%global baserelease 0
+%global baserelease 1
 %global fedora_build %{baserelease}
 
 # base_sublevel is the kernel version we're starting with and patching
@@ -720,6 +720,7 @@ Patch12026: block-stray-block-put-after-teardown.patch
 Patch12027: usb-add-quirk-for-logitech-webcams.patch
 Patch12028: fix-perf-build.patch
 Patch12029: crypto-register-cryptd-first.patch
+Patch12030: btrfs-use-do_div.patch
 
 
 # Runtime power management
@@ -1347,6 +1348,7 @@ ApplyPatch usb-add-quirk-for-logitech-webcams.patch
 
 ApplyPatch fix-perf-build.patch
 ApplyPatch crypto-register-cryptd-first.patch
+ApplyPatch btrfs-use-do_div.patch
 
 # Runtime PM
 #ApplyPatch linux-2.6-usb-pci-autosuspend.patch
@@ -2073,6 +2075,9 @@ fi
 #                 ||     ||
 %changelog
 * Fri Aug 19 2011 Josh Boyer <jwboyer at redhat.com>
+- Add patch from upstream to fix 64-bit divide error in btrfs
+
+* Fri Aug 19 2011 Josh Boyer <jwboyer at redhat.com>
 - Linux 3.1-rc2-git5
 - Change XHCI to builtin (rhbz 731706)
 - Add patch to fix race between cryptd and aesni (rhbz 721002)