At present dm/device.h includes the linux-compatible features. This
requires including linux/compat.h which in turn includes a lot of headers.
One of these is malloc.h which we thus end up including in every file in
U-Boot. Apart from the inefficiency of this, it is problematic for sandbox
which needs to use the system malloc() in some files.

Move the compatibility features into a separate header file.

Signed-off-by: Simon Glass <sjg@chromium.org>

The block count entry in the EXT4 filesystem disk structures uses
standard 512-bytes units for most of the typical files. The only
exception are HUGE files, which use the filesystem block size, but those
are not supported by uboot's EXT4 implementation anyway. This patch fixes
the EXT4 code to use proper unit count for inode block count. This fixes
errors reported by fsck.ext4 on disks with non-standard (i.e. 4KiB, in
case of new flash drives) PHYSICAL block size after using 'ext4write'
uboot's command.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>

Re-use the functions used to write/create a file, to support creation of a
symbolic link.
The difference with a regular file are small:
- The inode mode is flagged with S_IFLNK instead of S_IFREG
- The ext2_dirent's filetype is FILETYPE_SYMLINK instead of FILETYPE_REG
- Instead of storing the content of a file in allocated blocks, the path
to the target is stored. And if the target's path is short enough, no block
is allocated and the target's path is stored in ext2_inode.b.symlink

As with regulars files, if a file/symlink with the same name exits, it is
unlinked first and then re-created.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
[trini: Fix ext4 env code]
Signed-off-by: Tom Rini <trini@konsulko.com>

There is no need to modify the buffer passed to ext4fs_write_file().
The memset() call is not required here and was likely copied from the
equivalent part of the ext4fs_read_file() function where we do need it.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

When a file contains extents, U-Boot currently reads extent-related data
for each block in the file, even if that data is located in the same
block each time. This significantly slows down loading of files that use
extents. Implement a very dumb cache to prevent repeatedly reading the
same block. Files with extents now load as fast as files without.

Note: There are many cases where read_allocated_block() is called. This
patch only addresses one of those places; all others still read redundant
data in any case they did before. This is a minimal patch to fix the
load command; other cases aren't fixed.

Signed-off-by: Stephen Warren <swarren@nvidia.com>

U-Boot doesn't support metadata_csum feature. Writing to filesystem with
metadata_csum feature makes the filesystem corrupted and unbootable by
Linux:

[    2.527495] EXT4-fs (mmcblk0p2): ext4_check_descriptors: Checksum for group 0 failed (52188!=0)
[    2.537421] EXT4-fs (mmcblk0p2): ext4_check_descriptors: Checksum for group 1 failed (5262!=0)
...
[    2.653308] EXT4-fs (mmcblk0p2): ext4_check_descriptors: Checksum for group 14 failed (42611!=0)
[    2.662179] EXT4-fs (mmcblk0p2): ext4_check_descriptors: Checksum for group 15 failed (21527!=0)
[    2.687920] JBD2: journal checksum error
[    2.691982] EXT4-fs (mmcblk0p2): error loading journal
[    2.698292] VFS: Cannot open root device "mmcblk0p2" or unknown-block(179,2): error -74

Don't write to filesystem with meatadata_csum feature to not corrupt the
filesystem.

Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

Also adjust high 16/32 bits when free inode/block counts are modified.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>

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>

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>