Kernel26:Patch for EXT4 data loss.

1 files changed, 152 insertions, 0 deletions

diff --git a/abs/core-testing/kernel26/ext4.patch b/abs/core-testing/kernel26/ext4.patch
new file mode 100644
index 0000000..40ecfde
--- /dev/null
+++ b/abs/core-testing/kernel26/ext4.patch
@@ -0,0 +1,152 @@
+diff -ruaN linux-2.6.28.orig/fs/ext4/ext4.h linux-2.6.28/fs/ext4/ext4.h
+--- linux-2.6.28.orig/fs/ext4/ext4.h	2008-12-24 23:26:37.000000000 +0000
++++ linux-2.6.28/fs/ext4/ext4.h	2009-08-17 04:22:43.000000000 +0000
+@@ -254,6 +254,7 @@
+ #define EXT4_STATE_NEW			0x00000002 /* inode is newly created */
+ #define EXT4_STATE_XATTR		0x00000004 /* has in-inode xattrs */
+ #define EXT4_STATE_NO_EXPAND		0x00000008 /* No space for expansion */
++#define EXT4_STATE_DA_ALLOC_CLOSE	0x00000010 /* Alloc DA blks on close */
+ 
+ /* Used to pass group descriptor data when online resize is done */
+ struct ext4_new_group_input {
+@@ -301,7 +302,9 @@
+ #define EXT4_IOC_GROUP_EXTEND		_IOW('f', 7, unsigned long)
+ #define EXT4_IOC_GROUP_ADD		_IOW('f', 8, struct ext4_new_group_input)
+ #define EXT4_IOC_MIGRATE		_IO('f', 9)
++ /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
+  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
++#define EXT4_IOC_ALLOC_DA_BLKS		_IO('f', 12)
+ 
+ /*
+  * ioctl commands in 32 bit emulation
+@@ -1088,6 +1091,7 @@
+ extern void ext4_truncate(struct inode *);
+ extern void ext4_set_inode_flags(struct inode *);
+ extern void ext4_get_inode_flags(struct ext4_inode_info *);
++extern int ext4_alloc_da_blocks(struct inode *inode);
+ extern void ext4_set_aops(struct inode *inode);
+ extern int ext4_writepage_trans_blocks(struct inode *);
+ extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
+diff -ruaN linux-2.6.28.orig/fs/ext4/file.c linux-2.6.28/fs/ext4/file.c
+--- linux-2.6.28.orig/fs/ext4/file.c	2008-12-24 23:26:37.000000000 +0000
++++ linux-2.6.28/fs/ext4/file.c	2009-08-17 04:15:17.000000000 +0000
+@@ -33,6 +33,10 @@
+  */
+ static int ext4_release_file(struct inode *inode, struct file *filp)
+ {
++	if (EXT4_I(inode)->i_state & EXT4_STATE_DA_ALLOC_CLOSE) {
++		ext4_alloc_da_blocks(inode);
++		EXT4_I(inode)->i_state &= ~EXT4_STATE_DA_ALLOC_CLOSE;
++	}
+ 	/* if we are the last writer on the inode, drop the block reservation */
+ 	if ((filp->f_mode & FMODE_WRITE) &&
+ 			(atomic_read(&inode->i_writecount) == 1))
+diff -ruaN linux-2.6.28.orig/fs/ext4/inode.c linux-2.6.28/fs/ext4/inode.c
+--- linux-2.6.28.orig/fs/ext4/inode.c	2008-12-24 23:26:37.000000000 +0000
++++ linux-2.6.28/fs/ext4/inode.c	2009-08-17 04:34:48.000000000 +0000
+@@ -2686,6 +2686,42 @@
+ 	return;
+ }
+ 
++/*
++ * Force all delayed allocation blocks to be allocated for a given inode.
++ */
++int ext4_alloc_da_blocks(struct inode *inode)
++{
++	if (!EXT4_I(inode)->i_reserved_data_blocks &&
++	    !EXT4_I(inode)->i_reserved_meta_blocks)
++		return 0;
++	/*
++	 * We do something simple for now.  The filemap_flush() will
++	 * also start triggering a write of the data blocks, which is 
++	 * not strictly speaking necessary (and for users of
++	 * laptop_mode, not even desirable).  However, to do otherwise
++	 * would require replicating code paths in:
++	 *
++	 * ext4_da_writepages() ->
++	 *    write_cache_pages() ---> (via passed in callback function)
++	 *        __mpage_da_writepage() -->
++	 *           mpage_ad_bh_to_extent()
++	 *           mpage_da_map_blocks()
++	 *
++	 * The problem is that write_cache_pages(), and then redirty all of
++	 * the pages calling redirty_page_for_writeback() but that
++	 * would be ugly in the extreme.  So instead we would need to
++	 * replicate parts of the code in teh above functions,
++	 * simplifying them because we wouldn't actually intend to
++	 * write out the pages, but rather only collect contiguous
++	 * logical block extents, call the multi-block allocator, and
++	 * then update the buffer heads with the block allocations.
++	 *
++	 * For now, though we'll cheat by calling filemap_flush(),
++	 * which will map the blocks, and start the I/O, but not
++	 * actually wait for the I/O to complte.
++	 */
++	return filemap_flush(inode->i_mapping);
++}
+ 
+ /*
+  * bmap() is special.  It gets used by applications such as lilo and by
+@@ -3695,6 +3731,9 @@
+ 	if (!ext4_can_truncate(inode))
+ 		return;
+ 
++	if (inode->i_size == 0)
++		ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE;
++
+ 	if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
+ 		ext4_ext_truncate(inode);
+ 		return;
+diff -ruaN linux-2.6.28.orig/fs/ext4/ioctl.c linux-2.6.28/fs/ext4/ioctl.c
+--- linux-2.6.28.orig/fs/ext4/ioctl.c	2008-12-24 23:26:37.000000000 +0000
++++ linux-2.6.28/fs/ext4/ioctl.c	2009-08-17 04:38:43.000000000 +0000
+@@ -263,6 +263,20 @@
+ 		return err;
+ 	}
+ 
++	case EXT4_IOC_ALLOC_DA_BLKS:
++	{
++		int err;
++		if (!is_owner_or_cap(inode))
++			return -EACCES;
++
++		err = mnt_want_write(filp->f_path.mnt);
++		if (err)
++			return err;
++		err = ext4_alloc_da_blocks(inode);
++		mnt_drop_write(filp->f_path.mnt);
++		return err;
++	}
++
+ 	default:
+ 		return -ENOTTY;
+ 	}
+diff -ruaN linux-2.6.28.orig/fs/ext4/namei.c linux-2.6.28/fs/ext4/namei.c
+--- linux-2.6.28.orig/fs/ext4/namei.c	2008-12-24 23:26:37.000000000 +0000
++++ linux-2.6.28/fs/ext4/namei.c	2009-08-17 04:11:01.000000000 +0000
+@@ -2283,7 +2283,7 @@
+ 	struct inode *old_inode, *new_inode;
+ 	struct buffer_head *old_bh, *new_bh, *dir_bh;
+ 	struct ext4_dir_entry_2 *old_de, *new_de;
+-	int retval;
++	int retval, force_da_alloc = 0;
+ 
+ 	old_bh = new_bh = dir_bh = NULL;
+ 
+@@ -2421,6 +2421,7 @@
+ 		ext4_mark_inode_dirty(handle, new_inode);
+ 		if (!new_inode->i_nlink)
+ 			ext4_orphan_add(handle, new_inode);
++		force_da_alloc = 1;
+ 	}
+ 	retval = 0;
+ 
+@@ -2429,6 +2430,8 @@
+ 	brelse(old_bh);
+ 	brelse(new_bh);
+ 	ext4_journal_stop(handle);
++	if (retval == 0 && force_da_alloc)
++		ext4_alloc_da_blocks(old_inode);
+ 	return retval;
+ }
+