fs: ubifs: Do not free memory not allocated by ubifs ...

Since the switch to dentry cache implementation we no longer allocate
the super block, so we must not free it in the error path.

Fixes: ("4d2b23bcf9 fs: ubifs: Switch to dentry cache implementation")

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: ubifs: Switch to dentry cache implementation ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: dentry cache implementation ...

This adds the Linux dentry cache implementation to barebox.

Until now every filesystem driver resolves the full path to a file for
itself. This leads to code duplication and is error prone since
resolving paths is a complicated task. Also it can narrow down the
lookup performance since barebox only knows ASCII paths and has no way
of caching lookups.

With this patch we get the Linux dcache implementation. The path
resolving code from fs/namei.c is nearly taken as-is, minus the RCU
and locking code. Dcaching is made simple as of now: We simply cache
everything and never release any dentries. Although we do reference
counting for inodes and dentries it is effectively not used yet.
We never free anything until a fs is unmounted in which case we free
everything no matter if references are taken or not.

This patch also contains a wrapper in fs/legacy.c to support
filesystems with the old API.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: Add super_operations ...

Add a struct super_operations we can use later when we get a fs
implementation closer to Linux. Only add the functions we'll likely
need though.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ubifs: remove dead code ...

Remove code that was added to UBIFS for U-Boot but that is not needed
for barebox.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ubifs: Remove Linux struct definitions we already have ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ubifs: remove dead code ...

Remove stuff that was added to UBIFS for U-Boot which we do not need
because we already have it in the Linux header files.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ubifs: restore symlink support ...

In commit a63059d7 of the latest u-boot port, the function that
returns the inode number also resolves symlink. This prevents the
readlink entry point from doing its job and breaks the user command
readlink and the display of symlink with the ls command.
Remove the code following the link to restore original functionality.

Signed-off-by: Renaud Barbier <renaud.barbier@abaco.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ubifs: check return pointer properly ...

ubifs_iget() returns error codes encoded in the pointer,
so the NULL check will never be true.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/misc'

whole tree: remove trailing whitespaces ...

Signed-off-by: Du Huanpeng <u74147@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

string: Fix (v)asprintf prototypes ...

Our asprintf and vasprintf have different prototypes than the glibc
functions. This causes trouble when we want to share barebox code
with userspace code. Change the prototypes for (v)asprintf to match
the glibc prototypes. Since the current (v)asprintf are convenient
to use change the existing functions to b(v)asprintf.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

include: move crc specific stuff to crc.h ...

We have a crc.h, so move our crc function prototypes there to further
cleanup common.h.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ubifs: update implementation from u-boot v2016.03 ...

This updated code supports recovering from unclean unmounts when write
buffer size is larger than 8. Linux uses takes information into
consideration when checking for writes.
The following list shows the changes for each file done compared to
u-boot v2016.03 code.

Makefile
* Add gc.o, do not include header as in u-boot

budget.c:
* Replace __UBOOT__ with __BAREBOX__

debug.c:
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>
* Replace current->pid with 0

debug.h
* Replace __UBOOT__ with __BAREBOX__
* Add "0 &&" to ubifs_assert condition check
  U-Boot essentially disabled pr_crit output and dump_stack() is defined
  to do { } while (0), so ubifs_assert does nothing despite condition.

gc.c:
* Replace __UBOOT__ with __BAREBOX__

io.c:
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>

key.h:
* No changes

log.c:
* No changes

lprops.c:
* Replace __UBOOT__ with __BAREBOX__

lpt.c
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>
* Remove #include <ubi_uboot.h>

lpt_commit.c
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>

master.c
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>
* Remove #include <ubi_uboot.h>

misc.h
* Replace __UBOOT__ with __BAREBOX__
* Add #ifndef __BAREBOX__ around unneeded ubifs_current_time

orphan.c
* No changes

recovery.c
* Replace __UBOOT__ with __BAREBOX__

replay.c
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>

sb.c
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>
* Remove #include <ubi_uboot.h>
* rp_uid and rp_gid are still uid_t, not kuid_t, so remove .val

scan.c
* Replace __UBOOT__ with __BAREBOX__

super.c:
* Replaced current->pid with 0
* Replaced __UBOOT__ with __BAREBOX__
* Removed #include <ubi_uboot.h>
* Removed #include <memalign.h>
* Added #include <init.h>
* Replaced malloc_cache_aligned with kzalloc
* Replaced I_LOCK with I_SYNC
* i_uid and i_gid are still uid_t, not kuid_t, so remove .val
* Replaced string "U-Boot" with "Barebox"
* Add #ifndef __BAREBOX__ around open_ubi, sb_test, sb_set, ubifs_mount,
  kill_ubifs_super, ubifs_fs_type
* Do not call ubi_open_volume or ubi_close_volume in ubifs_fill_super
  Those will already be handled in ubifs_probe
* Replaced uboot_ubifs_mount with new ubifs_get_super implementation using
  existing functions alloc_super, alloc_ubifs_info

tnc.c
* Replace __UBOOT__ with __BAREBOX__
* Remove #include <linux/compat.h>

tnc_misc.c
* Replace __UBOOT__ with __BAREBOX__

ubifs-media.h
* Replace __UBOOT__ with __BAREBOX__

ubifs.c:
* Replaced __UBOOT__ with __BAREBOX__
* Adjusted header includes
* Removed DECLARE_GLOBAL_DATA_PTR
* Add static struct z_stream_s variable
* Add struct ubifs_priv delcaration
* Replaced zunzip with deflate_decompress call
* Add ifdef for disabling ZLIB and/or LZO support
* Replaced malloc_cache_aligned with kzalloc
* Added #ifndef __BAREBOX__ around filldir, ubifs_printdir,
  ubifs_set_blk_dev, ubifs_ls, ubifs_exists, ubifs_size, do_readpage,
  ubifs_read, ubifs_close, ubifs_load
* Make parameter filename const char* in ubifs_findfile
* Add UBIFS fs_driver_d implementation
* Add zlib_decomp_init, ubifs_init

ubifs.h:
* Replaced __UBOOT__ with __BAREBOX__
* Adjusted header includes
* Added old #define crc32
* Added helper around kmem*
* Added XATTR_LIST_MAX define
* Added #ifndef __BAREBOX__ around current_fs_time struct inode,
  struct super_block, file_system_type, dentry and friends which barebox
  already has
* Added #ifndef __BAREBOX__ around write_inode in super_operations to avoid
  declaration of writeback_control
* Change rp_uid and rp_gid to uid_t and gui_t
* Added struct device_d to struct ubifs_info
* Added forward declaration of ubifs_get_super

linux/fs.h:
* Make struct inode's i_nlink a union containing a non-const int __i_nlink
  while making i_nlink a const int

linux/fs.h:
* Add s_remove_count

linux/fs.h:
* Convert struct super_block.s_instances and
  struct file_system_type.fs_supers to hlist_head

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/linux-headers'

ubifs: Fix reading holes in files ...

When a whole block of 4KiB in an ubifs file is zero then the block is
not stored in the filesystem. read_block() returns -ENOENT in this case,
so this return value must be treated as success.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Introduce include/linux/mutex.h ...

Move mutex related defines to its original place.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Introduce include/linux/spinlock.h ...

Move spinlock related definitions to its original place.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Introduce include/linux/sched.h ...

Move cond_resched() from barebox-wrapper.h to its original
place.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: ubifs: move file and file_system_type definitions to linux/fs.h ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: ubifs: move path definition to include/linux/path.h ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: ubifs: move vfsmount definition to include/linux/mount.h ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: ubifs: move dcache related definitions to include/linux/dcache.h ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: move pgoff_t definition to include/linux/types.h ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: use linux/fs.h for file system related definitions ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: ubifs: remove redundant macro defines ...

Remove macros, that were already defined in linux/stat.h.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: move PAGE_CACHE definitions to include/linux/pagemap.h ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: introduce include/linux/fs.h ...

Move Linux file system structs from UBIFS to central place.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs: move struct timespec to include/linux/time.h ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

introduce strerrorp ...

putting an error pointer into strerror can be a bit confusing since
strerror takes a positive error code but PTR_ERR returns a negative
number, so we have to do strerror(-PTR_ERR(errp)). Some places got
this wrong already, so introduce a strerrorp function which directly
takes an error pointer.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>