u-boot/fs/btrfs/root.c
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

92 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* BTRFS filesystem implementation for U-Boot
*
* 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
*/
#include "btrfs.h"
static void read_root_item(struct btrfs_path *p, struct btrfs_root_item *item)
{
u32 len;
int reset = 0;
len = btrfs_path_item_size(p);
memcpy(item, btrfs_path_item_ptr(p, struct btrfs_root_item), len);
btrfs_root_item_to_cpu(item);
if (len < sizeof(*item))
reset = 1;
if (!reset && item->generation != item->generation_v2) {
if (item->generation_v2 != 0)
printf("%s: generation != generation_v2 in root item",
__func__);
reset = 1;
}
if (reset) {
memset(&item->generation_v2, 0,
sizeof(*item) - offsetof(struct btrfs_root_item,
generation_v2));
}
}
int btrfs_find_root(u64 objectid, struct btrfs_root *root,
struct btrfs_root_item *root_item)
{
struct btrfs_path path;
struct btrfs_root_item my_root_item;
if (!btrfs_search_tree_key_type(&btrfs_info.tree_root, objectid,
BTRFS_ROOT_ITEM_KEY, &path))
return -1;
if (!root_item)
root_item = &my_root_item;
read_root_item(&path, root_item);
if (root) {
root->objectid = objectid;
root->bytenr = root_item->bytenr;
root->root_dirid = root_item->root_dirid;
}
btrfs_free_path(&path);
return 0;
}
u64 btrfs_lookup_root_ref(u64 subvolid, struct btrfs_root_ref *refp, char *name)
{
struct btrfs_path path;
struct btrfs_key *key;
struct btrfs_root_ref *ref;
u64 res = -1ULL;
key = btrfs_search_tree_key_type(&btrfs_info.tree_root, subvolid,
BTRFS_ROOT_BACKREF_KEY, &path);
if (!key)
return -1ULL;
ref = btrfs_path_item_ptr(&path, struct btrfs_root_ref);
btrfs_root_ref_to_cpu(ref);
if (refp)
*refp = *ref;
if (name) {
if (ref->name_len > BTRFS_VOL_NAME_MAX) {
printf("%s: volume name too long: %u\n", __func__,
ref->name_len);
goto out;
}
memcpy(name, ref + 1, ref->name_len);
}
res = key->offset;
out:
btrfs_free_path(&path);
return res;
}