u-boot/fs/btrfs/conv-funcs.h
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
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>
2018-05-07 09:34:12 -04:00

175 lines
6.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Functions to convert BTRFS structures from disk to CPU endianness and back.
*
* 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
*/
#ifndef __BTRFS_CONV_FUNCS_H__
#define __BTRFS_CONV_FUNCS_H__
#include "ctree.h"
#include <u-boot/variadic-macro.h>
#include <asm/byteorder.h>
/* We are using variadic macros and C11 _Generic to achieve compact code.
We want to define macro DEFINE_CONV(x, ...), where the first argument is the
name of the structure for which it shall define conversion functions (the
names of the functions shall be x_to_cpu and x_to_disk), and the other
arguments are names of the members on which the functions shall do
endianness conversion. */
#if defined(__LITTLE_ENDIAN)
/* If the target machine is little endian, the conversion functions do
nothing, since the on disk format is little endian. */
# define DEFINE_CONV(n,...) \
static inline struct n *n##_to_disk(struct n * r) \
{ \
return r; \
} \
static inline struct n *n##_to_cpu(struct n * r) \
{ \
return r; \
}
# define DEFINE_CONV_ALT(n,a,...) \
static inline struct n *n##_to_disk_##a(struct n * r) \
{ \
return r; \
} \
static inline struct n *n##_to_cpu_##a(struct n * r) \
{ \
return r; \
}
#else /* !defined(__LITTLE_ENDIAN) */
/* Some structures contain not only scalar members, but compound types as well
(for example, struct btrfs_inode_item contains members of type struct
btrfs_timespec.
For these members we want to call the conversion function recursively, so
first we declare the functions taking pointers to this types (these function
will be defined later by the DEFINE_CONV macro) and then we define
correspond functions taking non-pointers, so that they can be used in the
expansion of the _Generic. */
# define DEFINE_CONV_FOR_STRUCT(n) \
static inline struct n * n##_to_disk(struct n *); \
static inline struct n * n##_to_cpu(struct n *); \
static inline struct n n##_to_disk_v(struct n x) { \
return *n##_to_disk(&x); \
} \
static inline struct n n##_to_cpu_v(struct n x) { \
return *n##_to_cpu(&x); \
}
DEFINE_CONV_FOR_STRUCT(btrfs_key)
DEFINE_CONV_FOR_STRUCT(btrfs_stripe)
DEFINE_CONV_FOR_STRUCT(btrfs_timespec)
DEFINE_CONV_FOR_STRUCT(btrfs_inode_item)
DEFINE_CONV_FOR_STRUCT(btrfs_root_backup)
DEFINE_CONV_FOR_STRUCT(btrfs_dev_item)
/* Now define the _Generic for both CPU to LE and LE to CPU */
# define DEFINE_CONV_CPU_TO_LE(x) \
(d->x) = _Generic((d->x), \
__u16: cpu_to_le16, \
__u32: cpu_to_le32, \
__u64: cpu_to_le64, \
struct btrfs_key: btrfs_key_to_disk_v, \
struct btrfs_stripe: btrfs_stripe_to_disk_v, \
struct btrfs_timespec: btrfs_timespec_to_disk_v, \
struct btrfs_inode_item: btrfs_inode_item_to_disk_v, \
struct btrfs_root_backup: btrfs_root_backup_to_disk_v, \
struct btrfs_dev_item: btrfs_dev_item_to_disk_v \
)((d->x));
# define DEFINE_CONV_LE_TO_CPU(x) \
(d->x) = _Generic((d->x), \
__u16: le16_to_cpu, \
__u32: le32_to_cpu, \
__u64: le64_to_cpu, \
struct btrfs_key: btrfs_key_to_cpu_v, \
struct btrfs_stripe: btrfs_stripe_to_cpu_v, \
struct btrfs_timespec: btrfs_timespec_to_cpu_v, \
struct btrfs_inode_item: btrfs_inode_item_to_cpu_v, \
struct btrfs_root_backup: btrfs_root_backup_to_cpu_v, \
struct btrfs_dev_item: btrfs_dev_item_to_cpu_v \
)((d->x));
# define DEFINE_CONV_ONE(t,n,m,...) \
static inline struct t * n(struct t * d) { \
CALL_MACRO_FOR_EACH(m, ##__VA_ARGS__) \
return d; \
}
/* Finally define the DEFINE_CONV macro */
# define DEFINE_CONV(n,...) \
DEFINE_CONV_ONE(n,n##_to_disk,DEFINE_CONV_CPU_TO_LE,##__VA_ARGS__) \
DEFINE_CONV_ONE(n,n##_to_cpu,DEFINE_CONV_LE_TO_CPU,##__VA_ARGS__)
# define DEFINE_CONV_ALT(n,a,...) \
DEFINE_CONV_ONE(n,n##_to_disk_##a,DEFINE_CONV_CPU_TO_LE, \
##__VA_ARGS__) \
DEFINE_CONV_ONE(n,n##_to_cpu_##a,DEFINE_CONV_LE_TO_CPU,##__VA_ARGS__)
#endif /* !defined(__LITTLE_ENDIAN) */
DEFINE_CONV(btrfs_key, objectid, offset)
DEFINE_CONV(btrfs_dev_item, devid, total_bytes, bytes_used, io_align, io_width,
sector_size, type, generation, start_offset, dev_group)
DEFINE_CONV(btrfs_stripe, devid, offset)
DEFINE_CONV(btrfs_chunk, length, owner, stripe_len, type, io_align, io_width,
sector_size, num_stripes, sub_stripes)
DEFINE_CONV(btrfs_free_space_entry, offset, bytes)
DEFINE_CONV(btrfs_free_space_header, location, generation, num_entries,
num_bitmaps)
DEFINE_CONV(btrfs_extent_item, refs, generation, flags)
DEFINE_CONV(btrfs_tree_block_info, key)
DEFINE_CONV(btrfs_extent_data_ref, root, objectid, offset, count)
DEFINE_CONV(btrfs_shared_data_ref, count)
DEFINE_CONV(btrfs_extent_inline_ref, offset)
DEFINE_CONV(btrfs_dev_extent, chunk_tree, chunk_objectid, chunk_offset, length)
DEFINE_CONV(btrfs_inode_ref, index, name_len)
DEFINE_CONV(btrfs_inode_extref, parent_objectid, index, name_len)
DEFINE_CONV(btrfs_timespec, sec, nsec)
DEFINE_CONV(btrfs_inode_item, generation, transid, size, nbytes, block_group,
nlink, uid, gid, mode, rdev, flags, sequence, atime, ctime, mtime,
otime)
DEFINE_CONV(btrfs_dir_log_item, end)
DEFINE_CONV(btrfs_dir_item, location, transid, data_len, name_len)
DEFINE_CONV(btrfs_root_item, inode, generation, root_dirid, bytenr, byte_limit,
bytes_used, last_snapshot, flags, refs, drop_progress,
generation_v2, ctransid, otransid, stransid, rtransid, ctime,
otime, stime, rtime)
DEFINE_CONV(btrfs_root_ref, dirid, sequence, name_len)
DEFINE_CONV(btrfs_file_extent_item, generation, ram_bytes, other_encoding,
disk_bytenr, disk_num_bytes, offset, num_bytes)
DEFINE_CONV_ALT(btrfs_file_extent_item, inl, generation, ram_bytes,
other_encoding)
DEFINE_CONV(btrfs_dev_replace_item, src_devid, cursor_left, cursor_right,
cont_reading_from_srcdev_mode, replace_state, time_started,
time_stopped, num_write_errors, num_uncorrectable_read_errors)
DEFINE_CONV(btrfs_block_group_item, used, chunk_objectid, flags)
DEFINE_CONV(btrfs_free_space_info, extent_count, flags)
DEFINE_CONV(btrfs_header, bytenr, flags, generation, owner, nritems)
DEFINE_CONV(btrfs_root_backup, tree_root, tree_root_gen, chunk_root,
chunk_root_gen, extent_root, extent_root_gen, fs_root, fs_root_gen,
dev_root, dev_root_gen, csum_root, csum_root_gen, total_bytes,
bytes_used, num_devices)
DEFINE_CONV(btrfs_super_block, bytenr, flags, magic, generation, root,
chunk_root, log_root, log_root_transid, total_bytes, bytes_used,
root_dir_objectid, num_devices, sectorsize, nodesize,
__unused_leafsize, stripesize, sys_chunk_array_size,
chunk_root_generation, compat_flags, compat_ro_flags,
incompat_flags, csum_type, dev_item, cache_generation,
uuid_tree_generation, super_roots[0], super_roots[1],
super_roots[2], super_roots[3])
DEFINE_CONV(btrfs_item, key, offset, size)
DEFINE_CONV(btrfs_key_ptr, key, blockptr, generation)
#endif /* __BTRFS_CONV_FUNCS_H__ */