Commit graph

455 commits

Author SHA1 Message Date
xypron.glpk@gmx.de
6568c731c4 yaffs2: remove redundant condition
If !parent, the changed line is not reached.
So there is no need to check the value again.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
2017-04-18 10:29:22 -04:00
Tyler Hall
d39a0d2c84 cramfs: basic symlink support
Handle symlinks to files in the current directory. Other cases could be
handled with additional code, but this is a start.

Add explicit errors for absolute paths and links found in the middle of
a path (directories). Other cases like '..' or '.' will result with the
file not being found as when those path components are explicitly
provided.

Add a helper to decompress a null-terminated link name which is shared
with cramfs_list_inode.

Signed-off-by: Tyler Hall <tylerwhall@gmail.com>
2017-04-18 10:27:58 -04:00
Tyler Hall
a6ea791cb9 cramfs: block pointers are 32 bits
Using a variably-sized type is incorrect here since we're reading a
fixed file format. Fixes cramfs on 64-bit platforms.

Signed-off-by: Tyler Hall <tylerwhall@gmail.com>
2017-04-18 10:27:57 -04:00
Masahiro Yamada
e856bdcfb4 flash: complete CONFIG_SYS_NO_FLASH move with renaming
We repeated partial moves for CONFIG_SYS_NO_FLASH, but this is
not completed. Finish this work by the tool.

During this move, let's rename it to CONFIG_MTD_NOR_FLASH.
Actually, we have more instances of "#ifndef CONFIG_SYS_NO_FLASH"
than those of "#ifdef CONFIG_SYS_NO_FLASH".  Flipping the logic will
make the code more readable.  Besides, negative meaning symbols do
not fit in obj-$(CONFIG_...) style Makefiles.

This commit was created as follows:

[1] Edit "default n" to "default y" in the config entry in
    common/Kconfig.

[2] Run "tools/moveconfig.py -y -r HEAD SYS_NO_FLASH"

[3] Rename the instances in defconfigs by the following:
  find . -path './configs/*_defconfig' | xargs sed -i \
  -e '/CONFIG_SYS_NO_FLASH=y/d' \
  -e 's/# CONFIG_SYS_NO_FLASH is not set/CONFIG_MTD_NOR_FLASH=y/'

[4] Change the conditionals by the following:
  find . -name '*.[ch]' | xargs sed -i \
  -e 's/ifndef CONFIG_SYS_NO_FLASH/ifdef CONFIG_MTD_NOR_FLASH/' \
  -e 's/ifdef CONFIG_SYS_NO_FLASH/ifndef CONFIG_MTD_NOR_FLASH/' \
  -e 's/!defined(CONFIG_SYS_NO_FLASH)/defined(CONFIG_MTD_NOR_FLASH)/' \
  -e 's/defined(CONFIG_SYS_NO_FLASH)/!defined(CONFIG_MTD_NOR_FLASH)/'

[5] Modify the following manually
  - Rename the rest of instances
  - Remove the description from README
  - Create the new Kconfig entry in drivers/mtd/Kconfig
  - Remove the old Kconfig entry from common/Kconfig
  - Remove the garbage comments from include/configs/*.h

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-02-12 14:30:25 -05:00
Stefan Brüns
b352caea75 fs/fat: Fix unaligned __u16 reads for FAT12 access
Doing unaligned reads is not supported on all architectures, use
byte sized reads of the little endian buffer.
Rename off16 to off8, as it reflects the buffer offset in byte
granularity (offset is in entry, i.e. 12 bit, granularity).
Fix a regression introduced in 8d48c92b45

Reported-by: Oleksandr Tymoshenko <gonzo@bluezbox.com>
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Tested-by: Oleksandr Tymoshenko <gonzo@bluezbox.com>
2017-01-28 14:04:51 -05:00
Patrick Delaunay
b331cd6204 cmd, disk: convert CONFIG_PARTITION_UUIDS, CMD_PART and CMD_GPT
We convert CONFIG_PARTITION_UUIDS to Kconfig first.  But in order to cleanly
update all of the config files we must also update CMD_PART and CMD_GPT to also
be in Kconfig in order to avoid complex logic elsewhere to update all of the
config files.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay73@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
2017-01-28 08:48:03 -05:00
Stefan Brüns
3cc5bbb8e6 fs/ext4: Initialize group descriptor size for revision level 0 filesystems
genext2fs creates revision level 0 filesystems, which are not readable
by u-boot due to the initialized group descriptor size field.
f798b1dda1

Reported-by: Kever Yang <kever.yang@rock-chips.com>
Reported-by: FrostyBytes@protonmail.com
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Tested-by: Kever Yang <kever.yang@rock-chips.com>
2016-12-27 11:24:18 -05:00
Stefan Brüns
8d48c92b45 fs/fat: simplify get_fatent for FAT12
Instead of shuffling bits from two adjacent 16 bit words, use one 16 bit
word with the appropriate byte offset in the buffer.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-12-27 11:24:14 -05:00
Stefan Brüns
b8948d2aef fs/fat: merge readwrite get_fatent_value() with readonly get_fatent()
get_fatent_value(...) flushes changed FAT entries to disk when fetching
the next FAT blocks, in every other aspect it is identical to
get_fatent(...).

Provide a stub implementation for flush_dirty_fat_buffer if
CONFIG_FAT_WRITE is not set. Calling flush_dirty_fat_buffer during read
only operation is fine as it checks if any buffers needs flushing.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-12-27 11:24:14 -05:00
Stefan Brüns
6c1a808052 fs/fat: Avoid corruption of sectors following the FAT
The FAT is read/flushed in segments of 6 (FATBUFBLOCKS) disk sectors. The
last segment may be less than 6 sectors, cap the length.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2016-12-27 11:24:13 -05:00
Philipp Skadorov
49abbd9cc3 fat: fatwrite: fix the command for FAT12
The u-boot command fatwrite empties FAT clusters from the beginning
till the end of the file.
Specifically for FAT12 it fails to detect the end of the file and goes
beyond the file bounds thus corrupting the file system.

Additionally, FAT entry chaining-up into a file is not implemented
for FAT12.

The users normally workaround this by re-formatting the partition as
FAT16/FAT32, like here:
https://github.com/FEDEVEL/openrex-uboot-v2015.10/issues/1

The patch fixes the bounds of a file and FAT12 entries chaining into
a file, including EOF markup.

Signed-off-by: Philipp Skadorov <philipp.skadorov@savoirfairelinux.com>
2016-12-27 11:24:13 -05:00
Tom Rini
0317724e6c sandboxfs: Fix resource leak
Now that we free resources in sandbox_fs_ls Coverity is letting us know
that in some cases we might leak.  So in case of error we should still
let os_dirent_free free anything that was allocated.

Fixes: 86167089b7 ("sandbox/fs: Free memory allocated by os_dirent_ls")
Reported-by: Coverity (CID: 153450)
Cc: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-12-02 10:37:47 -07:00
Tien Fong Chee
7aa1a6b71c fs/fat/fatwrite: Local variable as buffer to store dir_slot entries
fill_dir_slot use get_contents_vfatname_block as a temporary buffer for
constructing a list of dir_slot entries. To save the memory and providing
correct type of memory for above usage, a local buffer with accurate size
declaration is introduced.

The local array size 640 is used because for long file name entry,
each entry use 32 bytes, one entry can store up to 13 characters.
The maximum number of entry possible is 20. So, total size is
32*20=640bytes.

Signed-off-by: Genevieve Chan <ccheauya@altera.com>
Signed-off-by: Tien Fong Chee <tfchee@altera.com>
2016-11-28 20:09:45 -05:00
Stefan Brüns
66a47ff2d8 ext4: Allow reading files with non-zero offset, clamp read len
Support was already implemented, but not hooked up. This fixes several
fails in the test cases.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
2016-11-21 14:07:27 -05:00
Stefan Brüns
f81db56f2f ext4: Fix handling of sparse files
A sparse file may have regions not mapped by any extents, at the start
or at the end of the file, or anywhere between, thus not finding a
matching extent region is never an error.

Found by python filesystem tests.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-11-21 14:07:27 -05:00
Vagrant Cascadian
1381901e9a Fix spelling of "multiple".
Signed-off-by: Vagrant Cascadian <vagrant@debian.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-10-31 10:13:16 -04:00
Stefan Brüns
805e3e00f2 ext4: Only write journal entries for modified blocks in unlink_filename
Instead of creating a journal entry for each directory block, even
if the block is unmodified, only log the modified block.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-10-24 08:04:37 -04:00
Stefan Brüns
d1bdf22461 ext4: Fix handling of direntlen in unlink_filename
The direntlen checks were quite bogus, i.e. the loop termination used
"len + offset == blocksize" (exact match only), and checked for a
direntlen less than 0. The latter can never happen as the len is
unsigned, this has been reported by Coverity, CID 153384.

Use the same code as in search_dir for directory traversal. This code
has the correct checks for direntlen >= sizeof(struct dirent), and
offset < blocksize.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reported-by: Coverity (CID: 153383, 153384)
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
2016-10-24 08:04:36 -04:00
Stefan Brüns
15bf8c4f93 ext4: cleanup unlink_filename function
Use the same variable names as in search_dir, to make purpose of variables
more obvious.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
2016-10-24 08:04:36 -04:00
Stefan Brüns
86167089b7 sandbox/fs: Free memory allocated by os_dirent_ls
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Acked-by: Simon Glass <sjg@chromium.org>
2016-10-11 10:17:07 -06:00
Masahiro Yamada
1221ce459d treewide: replace #include <asm/errno.h> with <linux/errno.h>
Now, arch/${ARCH}/include/asm/errno.h and include/linux/errno.h have
the same content.  (both just wrap <asm-generic/errno.h>)

Replace all include directives for <asm/errno.h> with <linux/errno.h>.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
[trini: Fixup include/clk.]
Signed-off-by: Tom Rini <trini@konsulko.com>
2016-09-23 17:55:42 -04:00
Masahiro Yamada
b5bf5cb3b3 treewide: use #include <...> to include public headers
We are supposed to use #include <...> to include headers in the
public include paths.  We should use #include "..." only for headers
in local directories.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-09-23 17:53:56 -04:00
Stefan Brüns
b4976b49a0 ext4: Revert rejection of 64bit enabled ext4 fs
Enable mounting of ext4 fs with 64bit feature, as it is supported now.
These had been disabled in 6f94ab6656.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:20:16 -04:00
Stefan Brüns
749e93ee18 ext4: Respect group descriptor size when adjusting free counts
Also adjust high 16/32 bits when free inode/block counts are modified.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:20:16 -04:00
Stefan Brüns
688d0e79f6 ext4: Use helper function to access group descriptor and its fields
The descriptor size is variable, thus array indices are not generically
applicable. The larger group descriptors also contain e.g. high parts
of block numbers, which have to be read and written.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:20:15 -04:00
Stefan Brüns
f798b1dda1 ext4: Use correct descriptor size when reading the block group descriptor
The correct descriptor size must be used when calculating offsets, and
also to read the correct amount of data.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:18:57 -04:00
Stefan Brüns
9f5dd8b6e2 ext4: Add helper functions for block group descriptor field access
The helper functions encapsulate access of the block group descriptors,
independent of group descriptor size. The helpers also deal with the
endianess of the fields, and with split fields like free_blocks/
free_blocks_high.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:18:56 -04:00
Stefan Brüns
fc214ef909 ext4: determine group descriptor size for 64bit feature
If EXT4_FEATURE_INCOMPAT_64BIT is set, the descriptor can be read from
the superblocks, otherwise it defaults to 32.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:18:56 -04:00
Stefan Brüns
b1edcf0d80 ext4: Fix memory leak of journal buffer if block is updated multiple times
If the same block is updated multiple times in a row during a single
file system operation, gd_index is decremented to use the same journal
entry again. Avoid loosing the already allocated buffer.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:02:44 -04:00
Stefan Brüns
de9e831675 ext4: Correct block number handling, empty block vs. error code
read_allocated block may return block number 0, which is just an indicator
a chunk of the file is not backed by a block, i.e. it is sparse.

During file deletions, just continue with the next logical block, for other
operations treat blocknumber <= 0 as an error.

For writes, blocknumber 0 should never happen, as U-Boot always allocates
blocks for the whole file.  Reading already handles this correctly, i.e. the
read buffer is 0-fillled.

Not treating block 0 as sparse block leads to FS corruption, e.g.
	./sandbox/u-boot -c 'host bind 0 ./sandbox/test/fs/3GB.ext4.img ;
		ext4write host 0 0 /2.5GB.file 1 '
The 2.5GB.file from the fs test is actually a sparse file.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
2016-09-23 09:02:44 -04:00
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