linux/fs/btrfs
Chris Mason e3f24cc521 Btrfs: don't release pages when we can't clear the uptodate bits
Btrfs tracks uptodate state in an rbtree as well as in the
page bits.  This is supposed to enable us to use block sizes other than
the page size, but there are a few parts still missing before that
completely works.

But, our readpage routine trusts this additional range based tracking
of uptodateness, much in the same way the buffer head up to date bits
are trusted for the other filesystems.

The problem is that sometimes we need to allocate memory in order to
split records in the rbtree, even when we are just clearing bits.  This
can be difficult when our clearing function is called GFP_ATOMIC, which
can happen in the releasepage path.

So, what happens today looks like this:

releasepage called with GFP_ATOMIC
btrfs_releasepage calls clear_extent_bit
clear_extent_bit fails to allocate ram, leaving the up to date bit set
btrfs_releasepage returns success

The end result is the page being gone, but btrfs thinking the range is
up to date.   Later on if someone tries to read that same page, the
btrfs readpage code will return immediately thinking the page is already
up to date.

This commit fixes things to fail the releasepage when we can't clear the
extent state bits.  It covers both data pages and metadata tree blocks.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-02-14 13:04:01 -05:00
..
acl.c Merge branch 'bug-fixes' of git://repo.or.cz/linux-btrfs-devel into btrfs-38 2011-01-28 16:24:59 -05:00
async-thread.c Btrfs: don't walk around with task->state != TASK_RUNNING 2010-05-25 10:34:58 -04:00
async-thread.h Btrfs: fix deadlock on async thread startup 2009-10-05 09:44:45 -04:00
btrfs_inode.h btrfs: Allow to add new compression algorithm 2010-12-22 23:15:45 +08:00
compat.h Btrfs: drop remaining LINUX_KERNEL_VERSION checks and compat code 2009-01-06 09:38:55 -05:00
compression.c btrfs: Drop __exit attribute on btrfs_exit_compress 2011-02-06 07:19:19 -05:00
compression.h btrfs: Extract duplicate decompress code 2010-12-22 23:15:50 +08:00
ctree.c btrfs: check NULL or not 2011-01-16 11:30:20 -05:00
ctree.h Btrfs: forced readonly mounts on errors 2011-01-17 15:13:08 -05:00
delayed-ref.c Btrfs: Integrate metadata reservation with start_transaction 2010-05-25 10:34:50 -04:00
delayed-ref.h Btrfs: Integrate metadata reservation with start_transaction 2010-05-25 10:34:50 -04:00
dir-item.c Btrfs: Fix variables set but not read (bugs found by gcc 4.6) 2010-10-29 15:14:31 -04:00
disk-io.c Btrfs: fix page->private races 2011-02-14 13:03:52 -05:00
disk-io.h Btrfs: forced readonly mounts on errors 2011-01-17 15:13:08 -05:00
export.c btrfs: fix several uncheck memory allocations 2011-01-28 16:40:36 -05:00
export.h NFS support for btrfs - v3 2008-09-25 11:04:06 -04:00
extent_io.c Btrfs: don't release pages when we can't clear the uptodate bits 2011-02-14 13:04:01 -05:00
extent_io.h btrfs: Allow to add new compression algorithm 2010-12-22 23:15:45 +08:00
extent_map.c btrfs: Allow to add new compression algorithm 2010-12-22 23:15:45 +08:00
extent_map.h btrfs: Allow to add new compression algorithm 2010-12-22 23:15:45 +08:00
extent-tree.c Btrfs: exclude super blocks when we read in block groups 2011-02-06 07:17:44 -05:00
file-item.c Btrfs: do error checking in btrfs_del_csums 2011-01-28 16:42:34 -05:00
file.c Btrfs: Fix page count calculation 2011-02-07 14:13:51 -05:00
free-space-cache.c Btrfs: make sure search_bitmap finds something in remove_from_bitmap 2011-02-06 07:13:12 -05:00
free-space-cache.h Btrfs: load free space cache if it exists 2010-10-29 09:26:35 -04:00
hash.h Btrfs: remove crc32c.h and use libcrc32c directly. 2009-06-10 11:29:53 -04:00
inode-item.c Btrfs: Integrate metadata reservation with start_transaction 2010-05-25 10:34:50 -04:00
inode-map.c Btrfs: do not reuse objectid of deleted snapshot/subvol 2009-09-21 15:56:00 -04:00
inode.c btrfs: cleanup error handling in btrfs_unlink_inode() 2011-02-06 07:17:45 -05:00
ioctl.c btrfs: fix return value check of btrfs_start_transaction() 2011-02-01 07:17:27 -05:00
ioctl.h Merge branch 'lzo-support' of git://repo.or.cz/linux-btrfs-devel into btrfs-38 2011-01-16 11:25:54 -05:00
Kconfig btrfs: Add lzo compression support 2010-12-22 23:15:47 +08:00
locking.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
locking.h Btrfs: fix spinlock assertions on UP systems 2009-03-09 11:45:38 -04:00
lzo.c btrfs: Extract duplicate decompress code 2010-12-22 23:15:50 +08:00
Makefile btrfs: Add lzo compression support 2010-12-22 23:15:47 +08:00
ordered-data.c Btrfs: avoid uninit variable warnings in ordered-data.c 2011-01-31 20:33:37 -05:00
ordered-data.h btrfs: Allow to add new compression algorithm 2010-12-22 23:15:45 +08:00
orphan.c Btrfs: fixup return code for btrfs_del_orphan_item 2010-12-09 13:57:15 -05:00
print-tree.c btrfs: fix missing break in switch phrase 2011-01-28 16:40:37 -05:00
print-tree.h
ref-cache.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
ref-cache.h Btrfs: use RB_ROOT to intialize rb_trees instead of setting rb_node to NULL 2010-03-08 16:26:50 -05:00
relocation.c btrfs: fix return value check of btrfs_start_transaction() 2011-02-01 07:17:27 -05:00
root-tree.c Btrfs: cleanup warnings from gcc 4.6 (nonbugs) 2010-10-29 15:14:37 -04:00
struct-funcs.c Btrfs: Fix checkpatch.pl warnings 2009-01-05 21:25:51 -05:00
super.c btrfs: fix return value check of btrfs_start_transaction() 2011-02-01 07:17:27 -05:00
sysfs.c Driver core: Constify struct sysfs_ops in struct kobj_type 2010-03-07 17:04:49 -08:00
transaction.c btrfs: fix return value check of btrfs_join_transaction() 2011-01-28 16:40:37 -05:00
transaction.h Btrfs: Add readonly snapshots support 2010-12-23 08:49:17 +08:00
tree-defrag.c Btrfs: cleanup warnings from gcc 4.6 (nonbugs) 2010-10-29 15:14:37 -04:00
tree-log.c btrfs: fix return value check of btrfs_start_transaction() 2011-02-01 07:17:27 -05:00
tree-log.h Btrfs: Metadata ENOSPC handling for tree log 2010-05-25 10:34:53 -04:00
version.h Update Btrfs files for in-kernel usage 2008-09-25 15:41:59 -04:00
version.sh Btrfs: Fixes for 2.6.28-rc API changes 2008-11-19 21:17:22 -05:00
volumes.c btrfs: fix return value check of btrfs_start_transaction() 2011-02-01 07:17:27 -05:00
volumes.h btrfs: fix wrong free space information of btrfs 2011-01-16 11:30:19 -05:00
xattr.c Btrfs: Add readonly snapshots support 2010-12-23 08:49:17 +08:00
xattr.h btrfs: constify xattr_handler 2010-05-21 18:31:18 -04:00
zlib.c btrfs: Extract duplicate decompress code 2010-12-22 23:15:50 +08:00