Commit graph

425 commits

Author SHA1 Message Date
Stefan Brüns
b779e0290a ext4: remove duplicated block release code for extents
The data blocks are identical for files using traditional direct/indirect
block allocation scheme and extent trees, thus this code part can be
common. Only the code to deallocate the indirect blocks to record the
used blocks has to be seperate, respectively the code to release extent
tree index blocks.

Actually the code to release the extent tree index blocks is still missing,
but at least add a FIXME at the appropriate place.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:02:43 -04:00
Stefan Brüns
87f9fdc08d ext4: initialize full inode for inodes bigger than 128 bytes
Make sure the the extra_isize field (offset 128) is initialized to 0, to
mark any extra data as invalid.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:42 -04:00
Stefan Brüns
290ce2f95a ext4: Use correct value for inode size even on revision 0 filesystems
fs->inodesz is already correctly (i.e. dependent on fs revision)
initialized in ext4fs_mount.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:42 -04:00
Stefan Brüns
87a40b6e03 ext4: Fix memory leak in case of failure
temp_ptr should always be freed, even if the function is left via
goto fail.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:41 -04:00
Stefan Brüns
0ceef3d371 ext4: Avoid out-of-bounds access of block bitmap
If the blocksize is 1024, count is initialized with 1. Incrementing count
by 8 will never match (count == fs->blksz * 8), and ptr may be
incremented beyond the buffer end if the bitmap is filled. Add the
startblock offset after the loop.

Remove the second loop, as only the first iteration will be done.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:40 -04:00
Stefan Brüns
a9fa0ed183 ext4: After completely filled group, scan next group from the beginning
The last free block of a block group may be in its middle. After it has
been allocated, the next block group should be scanned from its beginning.

The following command triggers the bad behaviour (on a blocksize 1024 fs):

./sandbox/u-boot -c 'i=0; host bind 0 ./disk.raw ;
	while test $i -lt 260 ; do echo $i; setexpr i $i + 1;
		ext4write host 0:2 0 /X${i} 0x1450; done ;
	ext4write host 0:2 0 /X240 0x2000 ; '

When 'X240' is extended from 5200 byte to 8192 byte, the new blocks should
start from the first free block (8811), but it uses the blocks 8098-8103
and 16296-16297 -- 8103 + 1 + 8192 = 16296. This can be shown with
debugfs, commands 'ffb' and 'stat X240'.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:40 -04:00
Stefan Brüns
e927265225 ext4: Do not clear zalloc'ed buffers a second time
zero_buffer is never written, thus clearing it is pointless.
journal_buffer is completely initialized by ext4fs_devread (or in case
of failure, not used).

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:39 -04:00
Stefan Brüns
398d6fad92 ext4: Only update number of of unused inodes if GDT_CSUM feature is set
e2fsck warns about "Group descriptor 0 marked uninitialized without
feature set."
The bg_itable_unused field is only defined if FEATURE_RO_COMPAT_GDT_CSUM
is set, and should be set (kept) zero otherwise.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:39 -04:00
Stefan Brüns
b7dd40d052 ext4: Scan all directory blocks when looking up an entry
Scanning only the direct blocks of the directory file may falsely report
an existing file as nonexisting, and worse can also lead to creation
of a duplicate entry on file creation.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:38 -04:00
Stefan Brüns
10a7a1b8ba ext4: Avoid corruption of directories with hash tree indexes
While directories can be read using the old linear scan method, adding a
new file would require updating the index tree (alternatively, the whole
tree could be removed).

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:37 -04:00
Stefan Brüns
a321abd54f ext4: Scan all directory blocks for space when inserting a new entry
Previously, only the last directory block was scanned for available space.
Instead, scan all blocks back to front, and if no sufficient space is
found, eventually append a new block.
Blocks are only appended if the directory does not use extents or the new
block would require insertion of indirect blocks, as the old code does.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:36 -04:00
Stefan Brüns
b96c3c7292 ext4: Do not crash when trying to grow a directory using extents
The following command crashes u-boot:
./sandbox/u-boot -c 'i=0; host bind 0 ./sandbox/test/fs/3GB.ext4.img ;
  while test $i -lt 200 ; do echo $i; setexpr i $i + 1;
  ext4write host 0 0 /foobar${i} 0; done'

Previously, the code updated the direct_block even for extents, and
fortunately crashed before pushing garbage to the disk.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:36 -04:00
Stefan Brüns
a0d767e2c1 ext4: propagate error if creation of directory entry fails
In case the dir entry creation failed, ext4fs_write would later overwrite
a random inode, as inodeno was never initialized.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:35 -04:00
Stefan Brüns
76a29519ff ext4: fix possible crash on directory traversal, ignore deleted entries
The following command triggers a segfault in search_dir:
./sandbox/u-boot -c 'host bind 0 ./sandbox/test/fs/3GB.ext4.img ;
    ext4write host 0 0 /./foo 0x10'

The following command triggers a segfault in check_filename:
./sandbox/u-boot -c 'host bind 0 ./sandbox/test/fs/3GB.ext4.img ;
    ext4write host 0 0 /. 0x10'

"." is the first entry in the directory, thus previous_dir is NULL. The
whole previous_dir block in search_dir seems to be a bad copy from
check_filename(...). As the changed data is not written to disk, the
statement is mostly harmless, save the possible NULL-ptr reference.

Typically a file is unlinked by extending the direntlen of the previous
entry. If the entry is the first entry in the directory block, it is
invalidated by setting inode=0.

The inode==0 case is hard to trigger without crafted filesystems. It only
hits if the first entry in a directory block is deleted and later a lookup
for the entry (by name) is done.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 09:02:34 -04:00
Michael Walle
011bc3342a ext4: fix wrong usage of le32_to_cpu()
le32_to_cpu() must only convert the revision_level and not the boolean
result.

Signed-off-by: Michael Walle <michael@walle.cc>
2016-09-23 09:02:05 -04:00
Michael Walle
58a9ecbaf4 ext4: fix endianess problems in ext4 write support
All fields were accessed directly instead of using the proper byte swap
functions. Thus, ext4 write support was only usable on little-endian
architectures. Fix this.

Signed-off-by: Michael Walle <michael@walle.cc>
2016-09-23 09:02:04 -04:00
Michael Walle
7f101be314 ext4: use kernel names for byte swaps
Instead of __{be,le}{16,32}_to_cpu use {be,le}{16,32}_to_cpu.

Signed-off-by: Michael Walle <michael@walle.cc>
2016-09-23 09:02:02 -04:00
Michael Walle
2a0b7a971a ext4: change structure fields to __le/__be types
Change all the types of ext2/4 fields to little endian types and all the
JBD fields to big endian types. Now we can use sparse (make C=1) to check
for statements where we need byteswaps.

Signed-off-by: Michael Walle <michael@walle.cc>
2016-09-23 09:02:01 -04:00
Stefan Brüns
ae1755be37 fs/fat: Correct description of determine_fatent function
Current description does not match the function behaviour.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Acked-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 08:55:57 -04:00
Stefan Brüns
3c0ed9c3a5 fs/fat: Do not write unmodified fat entries to disk
The code caches 6 sectors of the FAT. On FAT traversal, the old contents
needs to be flushed to disk, but only if any FAT entries had been modified.
Explicitly flag the buffer on modification.

Currently, creating a new file traverses the whole FAT up to the first
free cluster and rewrites the on-disk blocks.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-09-23 08:55:56 -04:00
Stefan Brüns
ed76f91277 fs/fat: Remove two statements without effect
fatlength is a local variable which is no more used after the assignment.
s_name is not used in the function, save the strncpy.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-09-23 08:55:55 -04:00
Yaroslav K
cc7ed26934 cbfs: Fix incorrect CBFS file header size being used
This fixes incorrect filenames in cbfsls output.

Signed-off-by: Yaroslav K. <yar444@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
[clean up checkpatch errors and warnings]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
2016-08-16 11:44:09 +08:00
Tom Rini
6f94ab6656 ext4: Refuse to mount filesystems with 64bit feature set
With e2fsprogs after 1.43 the 64bit and metadata_csum features are
enabled by default.  The metadata_csum feature changes how
ext4_group_desc->bg_checksum is calculated, which would break write
support.  The 64bit feature however introduces changes such that it
cannot be read by implementations that do not support it.  Since we do
not support this, we must not mount it.

Cc: Stephen Warren <swarren@nvidia.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Lukasz Majewski <l.majewski@samsung.com>
Cc: Stefan Roese <sr@denx.de>
Reported-by: Andrew Bradford <andrew.bradford@kodakalaris.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
2016-08-05 07:27:14 -04:00
Guillaume GARDET
7a77e909a2 fs: cbfs: Fix build of fs/cbfs/cbfs.c when building u-boot sandbox on x86 32-bit
Fix the following build errors when building sandbox on x86 32-bit:

	In file included from fs/cbfs/cbfs.c:8:0:
	include/malloc.h:364:7: error: conflicting types for 'memset'
	void* memset(void*, int, size_t);
	^
	In file included from include/compiler.h:123:0,
			from include/cbfs.h:10,
			from fs/cbfs/cbfs.c:7:
	include/linux/string.h:78:15: note: previous declaration of 'memset' was here
	extern void * memset(void *,int,__kernel_size_t);
		^
	In file included from fs/cbfs/cbfs.c:8:0:
	include/malloc.h:365:7: error: conflicting types for 'memcpy'
	void* memcpy(void*, const void*, size_t);
	^
	In file included from include/compiler.h:123:0,
			from include/cbfs.h:10,
			from fs/cbfs/cbfs.c:7:
	include/linux/string.h:81:15: note: previous declaration of 'memcpy' was here
	extern void * memcpy(void *,const void *,__kernel_size_t);
		^
	scripts/Makefile.build:280: recipe for target 'fs/cbfs/cbfs.o' failed

Signed-off-by: Guillaume GARDET <guillaume.gardet@free.fr>
Cc: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-06-19 09:57:09 -04:00
Scott Wood
17cb4b8f32 mtd: nand: Add+use mtd_to/from_nand and nand_get/set_controller_data
These functions are part of the Linux 4.6 sync.  They are being added
before the main sync patch in order to make it easier to address the
issue across all NAND drivers (many/most of which do not closely track
their Linux counterparts) separately from other merge issues.

Signed-off-by: Scott Wood <oss@buserror.net>
2016-06-03 20:27:48 -05:00
Scott Wood
b616d9b0a7 nand: Embed mtd_info in struct nand_chip
nand_info[] is now an array of pointers, with the actual mtd_info
instance embedded in struct nand_chip.

This is in preparation for syncing the NAND code with Linux 4.6,
which makes the same change to struct nand_chip.  It's in a separate
commit due to the large amount of changes required to accommodate the
change to nand_info[].

Signed-off-by: Scott Wood <oss@buserror.net>
2016-06-03 20:27:48 -05:00
Scott Wood
151c06ec61 mtd: nand: Remove nand_info_t typedef
This typedef serves no purpose other than causing confusion with
struct nand_chip.

Signed-off-by: Scott Wood <oss@buserror.net>
2016-06-03 20:27:48 -05:00
Simon Glass
c649e3c91c dm: scsi: Rename CONFIG_CMD_SCSI to CONFIG_SCSI
This option currently enables both the command and the SCSI functionality.
Rename the existing option to CONFIG_SCSI since most of the code relates
to the feature.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-05-17 09:54:43 -06:00
Ronald Zachariah
37f23885e4 fs: ext4: fix symlink read function
The function ext4fs_read_symlink was unable to handle a symlink
which had target name of exactly 60 characters.

Signed-off-by: Ronald Zachariah <rozachar@cisco.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Cc: Tom Rini <trini@konsulko.com>
2016-05-02 13:33:19 -04:00
Heiko Schocher
b1d6590d35 ubifs: fix memory corruption in super.c
In list "super_blocks" ubifs collects allocated super_block
structs. U-Boot frees on unmount the allocated struct,
so the pointer stored in this list is free after the umount.
On a new ubifs mount, the new allocated super_block struct
get inserted into the super_blocks list ... which contains
now a freed pointer, and the list_add_tail() corrupts the
freed memory ...

2 solutions are possible:
- remove the super_block from the super_blocks list
  on umount

- as U-Boot does not use the super_blocks list ...
  remove it complete for U-Boot.

Both solutions should not introduce problems for porting
to newer linux version, so this patch removes the unused
super_blocks list, as it saves code size and execution
time.

Signed-off-by: Heiko Schocher <hs@denx.de>
2016-04-22 11:48:17 +02:00
Tom Rini
1c8fdf8779 jffs2: Fix set but not used warning
We only use 'ofs' in jffs2_sum_scan_sumnode when debugging as it's part
of a dbg_summary call.  Mark this as __maybe_unused.

Signed-off-by: Tom Rini <trini@konsulko.com>
2016-04-01 17:17:43 -04:00
Vagrant Cascadian
0af49b9575 Fix spelling of "supported/unsupported".
Signed-off-by: Vagrant Cascadian <vagrant@debian.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
2016-03-22 12:16:14 -04:00
Simon Glass
2a981dc2c6 dm: block: Adjust device calls to go through helpers function
To ease conversion to driver model, add helper functions which deal with
calling each block device method. With driver model we can reimplement these
functions with the same arguments.

Use inline functions to avoid increasing code size on some boards.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
2016-03-14 15:34:50 -06:00
Simon Glass
bcce53d048 dm: block: Rename device number member dev to devnum
This is a device number, and we want to use 'dev' to mean a driver model
device. Rename the member.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
2016-03-14 15:34:50 -06:00
Simon Glass
3e8bd46950 dm: part: Rename some partition functions
Rename three partition functions so that they start with part_. This makes
it clear what they relate to.

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
2016-03-14 15:34:50 -06:00
Simon Glass
e35929e4a1 dm: blk: Rename get_device_and_partition()
Rename this function to blk_get_device_part_str(). This is a better name
because it makes it clear that the function returns a block device and
parses a string.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
2016-03-14 15:34:50 -06:00
Simon Glass
4101f68792 dm: Drop the block_dev_desc_t typedef
Use 'struct' instead of a typdef. Also since 'struct block_dev_desc' is long
and causes 80-column violations, rename it to struct blk_desc.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
2016-03-14 15:34:50 -06:00
Masahiro Yamada
84b8bf6d5d bug.h: move BUILD_BUG_* defines to include/linux/bug.h
BUILD_BUG_* macros have been defined in several headers.  It would
be nice to collect them in include/linux/bug.h like Linux.

This commit is cherry-picking useful macros from include/linux/bug.h
of Linux 4.4.

I did not import BUILD_BUG_ON_MSG() because it would not work if it
is used with include/common.h in U-Boot.  I'd like to postpone it
until the root cause (the "error()" macro in include/common.h causes
the name conflict with "__attribute__((error()))") is fixed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
2016-01-25 10:39:59 -05:00
Tom Rini
5b8031ccb4 Add more SPDX-License-Identifier tags
In a number of places we had wordings of the GPL (or LGPL in a few
cases) license text that were split in such a way that it wasn't caught
previously.  Convert all of these to the correct SPDX-License-Identifier
tag.

Signed-off-by: Tom Rini <trini@konsulko.com>
2016-01-19 08:31:21 -05:00
Tom Rini
495c3a1e22 ext4_common.c: Clean up failure cases in alloc_triple_indirect_block
As noted by Coverity, when we have an error in
alloc_triple_indirect_block we will leak ti_pbuff_start_addr as it's not
being freed.  Further inspection here shows that we could also leak
ti_cbuff_start_addr in one corner case so free that as well.

Reported-by: Coverity (CID 131205, 131206)
Signed-off-by: Tom Rini <trini@konsulko.com>
2016-01-13 21:05:20 -05:00
Stephen Warren
7c4213f6a5 block: pass block dev not num to read/write/erase()
This will allow the implementation to make use of data in the block_dev
structure beyond the base device number. This will be useful so that eMMC
block devices can encompass the HW partition ID rather than treating this
out-of-band. Equally, the existence of the priv field is crying out for
this patch to exist.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
2016-01-13 21:05:18 -05:00
David Müller (ELSOFT AG)
e9cdf3b85e fs: handle the fileaddr variable in the same way as in the network case
Signed-off-by: David Müller <d.mueller@elsoft.ch>
2016-01-08 10:15:48 -05:00
Thomas Fitzsimmons
54d68e9333 fs: ext4: Prevent infinite loop in ext4fs_iterate_dir
If the ext3 journal gets out of sync with what is written on disk, for
example because of an unexpected power cut, ext4fs_read_file can
return an all-zero directory entry.  In that case, ext4fs_iterate_dir
would infinite loop.

This patch detects when a directory entry's direntlen member is 0 and
returns a failure status, which breaks out of the infinite loop.  As a
result, U-Boot will not find files that may subsequently be recovered
when the journal is replayed.

This is better behaviour than hanging in an infinite loop, but as a
further improvement maybe U-Boot could interpret the ext3 journal and
actually find the unsynced entries.

Signed-off-by: Thomas Fitzsimmons <fitzsim@cisco.com>
Reviewed-by: Stefan Roese <sr@denx.de>
2015-11-23 11:01:52 -05:00
Tom Rini
da58dec866 Various Makefiles: Add SPDX-License-Identifier tags
After consulting with some of the SPDX team, the conclusion is that
Makefiles are worth adding SPDX-License-Identifier tags too, and most of
ours have one.  This adds tags to ones that lack them and converts a few
that had full (or in one case, very partial) license blobs into the
equivalent tag.

Cc: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
2015-11-10 09:19:52 -05:00
Fabio Estevam
f8fdb81f6c compat: Remove is_power_of_2() definition
Use the is_power_of_2() definition from log2.h to align with the
kernel implementation.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Jagan Teki <jteki@openedev.com>
2015-11-05 16:46:59 -05:00
Heiko Schocher
0195a7bb36 ubi,ubifs: sync with linux v4.2
sync with linux v4.2

commit 64291f7db5bd8150a74ad2036f1037e6a0428df2
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun Aug 30 11:34:09 2015 -0700

    Linux 4.2

This update is needed, as it turned out, that fastmap
was in experimental/broken state in kernel v3.15, which
was the last base for U-Boot.

Signed-off-by: Heiko Schocher <hs@denx.de>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2015-10-26 09:22:36 +01:00
Hans de Goede
251cee0db2 ubifs: Add generic fs support
Add generic fs support, so that commands like ls, load and test -e can be
used on ubifs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2015-10-24 13:50:32 -04:00
Hans de Goede
29cc5bcadf ubifs: Add functions for generic fs use
Implement the necessary functions for implementing generic fs support
for ubifs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2015-10-24 13:50:32 -04:00
Hans de Goede
ad15749b6d ubifs: Modify ubifs u-boot wrapper function prototypes for generic fs use
Modify the ubifs u-boot wrapper function prototypes for generic fs use,
and give them their own header file.

This is a preparation patch for adding ubifs support to the generic fs
code from fs/fs.c.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2015-10-24 13:50:31 -04:00
Benoît Thébaudeau
1254b44a9f fs/fat/fat_write: Fix management of empty files
Overwriting an empty file not created by U-Boot did not work, and it
could even corrupt the FAT. Moreover, creating empty files or emptying
existing files allocated a cluster, which is not standard.

Fix this by always keeping empty files clusterless as specified by
Microsoft (the start cluster must be set to 0 in the directory entry in
that case), and by supporting overwriting such files.

Signed-off-by: Benoît Thébaudeau <benoit@wsystem.com>
2015-10-11 17:12:08 -04:00