linux-toradex.git/fs/fat/fat.h, branch v3.19.3

fat: fix data past EOF resulting from fsx testsuite

2014-12-13T20:42:51+00:00

When running FSX with direct I/O mode, fsx resulted in DATA past EOF issues.

  fsx ./file2 -Z -r 4096 -w 4096
  ...
  ..
  truncating to largest ever: 0x907c
  fallocating to largest ever: 0x11137
  truncating to largest ever: 0x2c6fe
  truncating to largest ever: 0x2cfdf
  fallocating to largest ever: 0x40000
  Mapped Read: non-zero data past EOF (0x18628) page offset 0x629 is 0x2a4e
  ...
  ..

The reason being, it is doing a truncate down, but the zeroing does not
happen on the last block boundary when offset is not aligned.  Even though
it calls truncate_setsize()->truncate_inode_pages()->
truncate_inode_pages_range() and considers the partial zeroout but it
retrieves the page using find_lock_page() - which only looks the page in
the cache.  So, zeroing out does not happen in case of direct IO.

Make a truncate page based around block_truncate_page for FAT filesystem
and invoke that helper to zerout in case the offset is not aligned with
the blocksize.

Signed-off-by: Namjae Jeon 
Signed-off-by: Amit Sahrawat 
Acked-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fs/fat/: add support for DOS 1.x formatted volumes

2014-06-06T23:08:10+00:00

Add structure for parsed BPB information, struct fat_bios_param_block,
and move all of the deserialization and validation logic from
fat_fill_super() into fat_read_bpb().

Add a 'dos1xfloppy' mount option to infer DOS 2.x BIOS Parameter Block
defaults from block device geometry for ancient floppies and floppy
images, as a fall-back from the default BPB parsing logic.

When fat_read_bpb() finds an invalid FAT filesystem and dos1xfloppy is
set, fall back to fat_read_static_bpb().  fat_read_static_bpb()
validates that the entire BPB is zero, and that the floppy has a
DOS-style 8086 code bootstrapping header.  Then it fills in default BPB
values from media size and a table.[0]

Media size is assumed to be static for archaic FAT volumes.  See also:
[1].

Fixes kernel.org bug #42617.

[0]: https://en.wikipedia.org/wiki/File_Allocation_Table#Exceptions
[1]: http://www.win.tue.nl/~aeb/linux/fs/fat/fat-1.html

[hirofumi@mail.parknet.co.jp: fix missed error code]
Signed-off-by: Conrad Meyer 
Acked-by: OGAWA Hirofumi 
Signed-off-by: OGAWA Hirofumi 
Tested-by: Alan Cox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fat: rcu-delay unloading nls and freeing sbi

2013-10-25T03:43:28+00:00

makes ->d_hash() and ->d_compare() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro

fatfs: add FAT_IOCTL_GET_VOLUME_ID

2013-07-09T17:33:25+00:00

This patch, originally from Android kernel, adds vfat ioctl command
FAT_IOCTL_GET_VOLUME_ID, with this command we can get the vfat volume ID
using following code:

	ioctl(fd, FAT_IOCTL_GET_VOLUME_ID, &volume_ID)

This patch is a modified version of the patch by Mike Lockwood, with
changes from Dmitry Pervushin, who noticed the original patch makes some
volume IDs abiguous with error returns: for example, if volume id is
0xFFFFFDAD, that matches -ENOIOCTLCMD, we get "FFFFFFFF" from the user
space.

So add a parameter to ioctl to get the correct volume ID.

Android uses vfat volume ID to identify different sd card, when a new sd
card is inserted to device, android can scan the media on it and pop up
new contents.

Signed-off-by: Bintian Wang 
Cc: dmitry pervushin 
Cc: Mike Lockwood 
Cc: Colin Cross 
Acked-by: OGAWA Hirofumi 
Cc: John Stultz 
Cc: Sean McNeil 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fat (exportfs): rebuild directory-inode if fat_dget()

2013-04-30T01:28:41+00:00

This patch enables rebuilding of directory inodes which are not present in
the cache.This is done by traversing the disk clusters to find the
directory entry of the parent directory and using its i_pos to build the
inode.

The traversal is done by fat_scan_logstart() which is similar to
fat_scan() but matches i_pos values instead of names.fat_scan_logstart()
needs an inode parameter to work, for which a dummy inode is created by
it's caller fat_rebuild_parent().  This dummy inode is destroyed after the
traversal completes.

All this is done  only if the nostale_ro nfs mount option is specified.

Signed-off-by: Namjae Jeon 
Signed-off-by: Ravishankar N 
Signed-off-by: Amit Sahrawat 
Acked-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fat (exportfs): rebuild inode if ilookup() fails

2013-04-30T01:28:41+00:00

If the cache lookups fail,use the i_pos value to find the directory entry
of the inode and rebuild the inode.Since this involves accessing the FAT
media, do this only if the nostale_ro nfs mount option is specified.

Signed-off-by: Namjae Jeon 
Signed-off-by: Ravishankar N 
Signed-off-by: Amit Sahrawat 
Acked-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fat: restructure export_operations

2013-04-30T01:28:40+00:00

Define two nfs export_operation structures,one for 'stale_rw' mounts and
the other for 'nostale_ro'.  The latter uses i_pos as a basis for encoding
and decoding file handles.

Also, assign i_pos to kstat->ino.  The logic for rebuilding the inode is
added in the subsequent patches.

Signed-off-by: Namjae Jeon 
Signed-off-by: Ravishankar N 
Signed-off-by: Amit Sahrawat 
Acked-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fat: introduce a helper fat_get_blknr_offset()

2013-04-30T01:28:40+00:00

Introduce helper function to get the block number and offset for a given
i_pos value.  Use it in __fat_write_inode() now and later on in nfs.c

Signed-off-by: Namjae Jeon 
Signed-off-by: Ravishankar N 
Signed-off-by: Amit Sahrawat 
Acked-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fat: move fat_i_pos_read to fat.h

2013-04-30T01:28:40+00:00

Move fat_i_pos_read to fat.h so that it can be called from nfs.c in the
subsequent patches to encode the file handle.

Signed-off-by: Namjae Jeon 
Signed-off-by: Ravishankar N 
Signed-off-by: Amit Sahrawat 
Acked-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fat: introduce 2 new values for the -o nfs mount option

2013-04-30T01:28:40+00:00

This patchset eliminates the client side ESTALE errors when a FAT
partition exported over NFS has its dentries evicted from the cache.  The
idea is to find the on-disk location_'i_pos' of the dirent of the inode
that has been evicted and use it to rebuild the inode.

This patch:

Provide two possible values 'stale_rw' and 'nostale_ro' for the -o nfs
mount option.The first one allows all file operations but does not reduce
ESTALE errors on memory constrained systems.  The second one eliminates
ESTALE errors but mounts the filesystem as read-only.  Not specifying a
value defaults to 'stale_rw'.

Signed-off-by: Namjae Jeon 
Signed-off-by: Ravishankar N 
Signed-off-by: Amit Sahrawat 
Acked-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds