linux.git/fs/ext2/ext2.h, branch v4.9

ext2: use iomap to implement DAX

2016-09-19T01:30:29+00:00

Signed-off-by: Christoph Hellwig 
Reviewed-by: Ross Zwisler 
Signed-off-by: Dave Chinner

Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-08-06T13:49:02+00:00

Pull qstr constification updates from Al Viro:
 "Fairly self-contained bunch - surprising lot of places passes struct
  qstr * as an argument when const struct qstr * would suffice; it
  complicates analysis for no good reason.

  I'd prefer to feed that separately from the assorted fixes (those are
  in #for-linus and with somewhat trickier topology)"

* 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  qstr: constify instances in adfs
  qstr: constify instances in lustre
  qstr: constify instances in f2fs
  qstr: constify instances in ext2
  qstr: constify instances in vfat
  qstr: constify instances in procfs
  qstr: constify instances in fuse
  qstr constify instances in fs/dcache.c
  qstr: constify instances in nfs
  qstr: constify instances in ocfs2
  qstr: constify instances in autofs4
  qstr: constify instances in hfs
  qstr: constify instances in hfsplus
  qstr: constify instances in logfs
  qstr: constify dentry_init_security

qstr: constify instances in ext2

2016-07-30T16:25:49+00:00

Signed-off-by: Al Viro

ext2: fix filesystem deadlock while reading corrupted xattr block

2016-07-06T02:02:41+00:00

This bug can be reproducible with fsfuzzer, although, I couldn't reproduce it
100% of my tries, it is quite easily reproducible.

During the deletion of an inode, ext2_xattr_delete_inode() does not check if the
block pointed by EXT2_I(inode)->i_file_acl is a valid data block, this might
lead to a deadlock, when i_file_acl == 1, and the filesystem block size is 1024.

In that situation, ext2_xattr_delete_inode, will load the superblock's buffer
head (instead of a valid i_file_acl block), and then lock that buffer head,
which, ext2_sync_super will also try to lock, making the filesystem deadlock in
the following stack trace:

root     17180  0.0  0.0 113660   660 pts/0    D+   07:08   0:00 rmdir
/media/test/dir1

[] __sync_dirty_buffer+0xaf/0x100
[] sync_dirty_buffer+0x13/0x20
[] ext2_sync_super+0xb7/0xc0 [ext2]
[] ext2_error+0x119/0x130 [ext2]
[] ext2_free_blocks+0x83/0x350 [ext2]
[] ext2_xattr_delete_inode+0x173/0x190 [ext2]
[] ext2_evict_inode+0xc9/0x130 [ext2]
[] evict+0xb3/0x180
[] iput+0x1b8/0x240
[] d_delete+0x11c/0x150
[] vfs_rmdir+0xfe/0x120
[] do_rmdir+0x17e/0x1f0
[] SyS_rmdir+0x16/0x20
[] entry_SYSCALL_64_fastpath+0x1a/0xa4
[] 0xffffffffffffffff

Fix this by using the same approach ext4 uses to test data blocks validity,
implementing ext2_data_block_valid.

An another possibility when the superblock is very corrupted, is that i_file_acl
is 1, block_count is 1 and first_data_block is 0. For such situations, we might
have i_file_acl pointing to a 'valid' block, but still step over the superblock.
The approach I used was to also test if the superblock is not in the range
described by ext2_data_block_valid() arguments

Signed-off-by: Carlos Maiolino 
Signed-off-by: Theodore Ts'o

mbcache2: rename to mbcache

2016-02-23T03:35:22+00:00

Since old mbcache code is gone, let's rename new code to mbcache since
number 2 is now meaningless. This is just a mechanical replacement.

Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o

ext2: convert to mbcache2

2016-02-22T16:56:38+00:00

The conversion is generally straightforward. We convert filesystem from
a global cache to per-fs one. Similarly to ext4 the tricky part is that
xattr block corresponding to found mbcache entry can get freed before we
get buffer lock for that block. So we have to check whether the entry is
still valid after getting the buffer lock.

Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o

ext2: Add locking for DAX faults

2015-10-19T12:40:54+00:00

Add locking to ensure that DAX faults are isolated from ext2 operations
that modify the data blocks allocation for an inode.  This is intended to
be analogous to the work being done in XFS by Dave Chinner:

http://www.spinics.net/lists/linux-fsdevel/msg90260.html

Compared with XFS the ext2 case is greatly simplified by the fact that ext2
already allocates and zeros new blocks before they are returned as part of
ext2_get_block(), so DAX doesn't need to worry about getting unmapped or
unwritten buffer heads.

This means that the only work we need to do in ext2 is to isolate the DAX
faults from inode block allocation changes.  I believe this just means that
we need to isolate the DAX faults from truncate operations.

The newly introduced dax_sem is intended to replicate the protection
offered by i_mmaplock in XFS.  In addition to truncate the i_mmaplock also
protects XFS operations like hole punching, fallocate down, extent
manipulation IOCTLS like xfs_ioc_space() and extent swapping.  Truncate is
the only one of these operations supported by ext2.

Signed-off-by: Ross Zwisler 
Signed-off-by: Jan Kara

dax: unify ext2/4_{dax,}_file_operations

2015-04-15T23:35:20+00:00

The original dax patchset split the ext2/4_file_operations because of the
two NULL splice_read/splice_write in the dax case.

In the vfs if splice_read/splice_write are NULL we then call
default_splice_read/write.

What we do here is make generic_file_splice_read aware of IS_DAX() so the
original ext2/4_file_operations can be used as is.

For write it appears that iter_file_splice_write is just fine.  It uses
the regular f_op->write(file,..) or new_sync_write(file, ...).

Signed-off-by: Boaz Harrosh 
Reviewed-by: Jan Kara 
Cc: Dave Chinner 
Cc: Matthew Wilcox 
Cc: Hugh Dickins 
Cc: Mel Gorman 
Cc: Kirill A. Shutemov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext2: get rid of most mentions of XIP in ext2

2015-02-17T01:56:04+00:00

To help people transition, accept the 'xip' mount option (and report it in
/proc/mounts), but print a message encouraging people to switch over to
the 'dax' option.

Signed-off-by: Matthew Wilcox 
Reviewed-by: Mathieu Desnoyers 
Cc: Andreas Dilger 
Cc: Boaz Harrosh 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Jan Kara 
Cc: Jens Axboe 
Cc: Kirill A. Shutemov 
Cc: Randy Dunlap 
Cc: Ross Zwisler 
Cc: Theodore Ts'o 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ext2: remove ext2_aops_xip

2015-02-17T01:56:04+00:00

We shouldn't need a special address_space_operations any more

Signed-off-by: Matthew Wilcox 
Reviewed-by: Mathieu Desnoyers 
Cc: Andreas Dilger 
Cc: Boaz Harrosh 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Jan Kara 
Cc: Jens Axboe 
Cc: Kirill A. Shutemov 
Cc: Randy Dunlap 
Cc: Ross Zwisler 
Cc: Theodore Ts'o 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds