u-boot/fs/btrfs/inode.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

383 lines
7.9 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"
#include <malloc.h>
u64 btrfs_lookup_inode_ref(struct btrfs_root *root, u64 inr,
struct btrfs_inode_ref *refp, char *name)
{
struct btrfs_path path;
struct btrfs_key *key;
struct btrfs_inode_ref *ref;
u64 res = -1ULL;
key = btrfs_search_tree_key_type(root, inr, BTRFS_INODE_REF_KEY,
&path);
if (!key)
return -1ULL;
ref = btrfs_path_item_ptr(&path, struct btrfs_inode_ref);
btrfs_inode_ref_to_cpu(ref);
if (refp)
*refp = *ref;
if (name) {
if (ref->name_len > BTRFS_NAME_MAX) {
printf("%s: inode 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;
}
int btrfs_lookup_inode(const struct btrfs_root *root,
struct btrfs_key *location,
struct btrfs_inode_item *item,
struct btrfs_root *new_root)
{
struct btrfs_root tmp_root = *root;
struct btrfs_path path;
int res = -1;
if (location->type == BTRFS_ROOT_ITEM_KEY) {
if (btrfs_find_root(location->objectid, &tmp_root, NULL))
return -1;
location->objectid = tmp_root.root_dirid;
location->type = BTRFS_INODE_ITEM_KEY;
location->offset = 0;
}
if (btrfs_search_tree(&tmp_root, location, &path))
return res;
if (btrfs_comp_keys(location, btrfs_path_leaf_key(&path)))
goto out;
if (item) {
*item = *btrfs_path_item_ptr(&path, struct btrfs_inode_item);
btrfs_inode_item_to_cpu(item);
}
if (new_root)
*new_root = tmp_root;
res = 0;
out:
btrfs_free_path(&path);
return res;
}
int btrfs_readlink(const struct btrfs_root *root, u64 inr, char *target)
{
struct btrfs_path path;
struct btrfs_key key;
struct btrfs_file_extent_item *extent;
const char *data_ptr;
int res = -1;
key.objectid = inr;
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = 0;
if (btrfs_search_tree(root, &key, &path))
return -1;
if (btrfs_comp_keys(&key, btrfs_path_leaf_key(&path)))
goto out;
extent = btrfs_path_item_ptr(&path, struct btrfs_file_extent_item);
if (extent->type != BTRFS_FILE_EXTENT_INLINE) {
printf("%s: Extent for symlink %llu not of INLINE type\n",
__func__, inr);
goto out;
}
btrfs_file_extent_item_to_cpu_inl(extent);
if (extent->compression != BTRFS_COMPRESS_NONE) {
printf("%s: Symlink %llu extent data compressed!\n", __func__,
inr);
goto out;
} else if (extent->encryption != 0) {
printf("%s: Symlink %llu extent data encrypted!\n", __func__,
inr);
goto out;
} else if (extent->ram_bytes >= btrfs_info.sb.sectorsize) {
printf("%s: Symlink %llu extent data too long (%llu)!\n",
__func__, inr, extent->ram_bytes);
goto out;
}
data_ptr = (const char *) extent
+ offsetof(struct btrfs_file_extent_item, disk_bytenr);
memcpy(target, data_ptr, extent->ram_bytes);
target[extent->ram_bytes] = '\0';
res = 0;
out:
btrfs_free_path(&path);
return res;
}
/* inr must be a directory (for regular files with multiple hard links this
function returns only one of the parents of the file) */
static u64 get_parent_inode(struct btrfs_root *root, u64 inr,
struct btrfs_inode_item *inode_item)
{
struct btrfs_key key;
u64 res;
if (inr == BTRFS_FIRST_FREE_OBJECTID) {
if (root->objectid != btrfs_info.fs_root.objectid) {
u64 parent;
struct btrfs_root_ref ref;
parent = btrfs_lookup_root_ref(root->objectid, &ref,
NULL);
if (parent == -1ULL)
return -1ULL;
if (btrfs_find_root(parent, root, NULL))
return -1ULL;
inr = ref.dirid;
}
if (inode_item) {
key.objectid = inr;
key.type = BTRFS_INODE_ITEM_KEY;
key.offset = 0;
if (btrfs_lookup_inode(root, &key, inode_item, NULL))
return -1ULL;
}
return inr;
}
res = btrfs_lookup_inode_ref(root, inr, NULL, NULL);
if (res == -1ULL)
return -1ULL;
if (inode_item) {
key.objectid = res;
key.type = BTRFS_INODE_ITEM_KEY;
key.offset = 0;
if (btrfs_lookup_inode(root, &key, inode_item, NULL))
return -1ULL;
}
return res;
}
static inline int next_length(const char *path)
{
int res = 0;
while (*path != '\0' && *path != '/' && res <= BTRFS_NAME_LEN)
++res, ++path;
return res;
}
static inline const char *skip_current_directories(const char *cur)
{
while (1) {
if (cur[0] == '/')
++cur;
else if (cur[0] == '.' && cur[1] == '/')
cur += 2;
else
break;
}
return cur;
}
u64 btrfs_lookup_path(struct btrfs_root *root, u64 inr, const char *path,
u8 *type_p, struct btrfs_inode_item *inode_item_p,
int symlink_limit)
{
struct btrfs_dir_item item;
struct btrfs_inode_item inode_item;
u8 type = BTRFS_FT_DIR;
int len, have_inode = 0;
const char *cur = path;
if (*cur == '/') {
++cur;
inr = root->root_dirid;
}
do {
cur = skip_current_directories(cur);
len = next_length(cur);
if (len > BTRFS_NAME_LEN) {
printf("%s: Name too long at \"%.*s\"\n", __func__,
BTRFS_NAME_LEN, cur);
return -1ULL;
}
if (len == 1 && cur[0] == '.')
break;
if (len == 2 && cur[0] == '.' && cur[1] == '.') {
cur += 2;
inr = get_parent_inode(root, inr, &inode_item);
if (inr == -1ULL)
return -1ULL;
type = BTRFS_FT_DIR;
continue;
}
if (!*cur)
break;
if (btrfs_lookup_dir_item(root, inr, cur, len, &item))
return -1ULL;
type = item.type;
have_inode = 1;
if (btrfs_lookup_inode(root, &item.location, &inode_item, root))
return -1ULL;
if (item.type == BTRFS_FT_SYMLINK && symlink_limit >= 0) {
char *target;
if (!symlink_limit) {
printf("%s: Too much symlinks!\n", __func__);
return -1ULL;
}
target = malloc(min(inode_item.size + 1,
(u64) btrfs_info.sb.sectorsize));
if (!target)
return -1ULL;
if (btrfs_readlink(root, item.location.objectid,
target)) {
free(target);
return -1ULL;
}
inr = btrfs_lookup_path(root, inr, target, &type,
&inode_item, symlink_limit - 1);
free(target);
if (inr == -1ULL)
return -1ULL;
} else if (item.type != BTRFS_FT_DIR && cur[len]) {
printf("%s: \"%.*s\" not a directory\n", __func__,
(int) (cur - path + len), path);
return -1ULL;
} else {
inr = item.location.objectid;
}
cur += len;
} while (*cur);
if (type_p)
*type_p = type;
if (inode_item_p) {
if (!have_inode) {
struct btrfs_key key;
key.objectid = inr;
key.type = BTRFS_INODE_ITEM_KEY;
key.offset = 0;
if (btrfs_lookup_inode(root, &key, &inode_item, NULL))
return -1ULL;
}
*inode_item_p = inode_item;
}
return inr;
}
u64 btrfs_file_read(const struct btrfs_root *root, u64 inr, u64 offset,
u64 size, char *buf)
{
struct btrfs_path path;
struct btrfs_key key;
struct btrfs_file_extent_item *extent;
int res = 0;
u64 rd, rd_all = -1ULL;
key.objectid = inr;
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = offset;
if (btrfs_search_tree(root, &key, &path))
return -1ULL;
if (btrfs_comp_keys(&key, btrfs_path_leaf_key(&path)) < 0) {
if (btrfs_prev_slot(&path))
goto out;
if (btrfs_comp_keys_type(&key, btrfs_path_leaf_key(&path)))
goto out;
}
rd_all = 0;
do {
if (btrfs_comp_keys_type(&key, btrfs_path_leaf_key(&path)))
break;
extent = btrfs_path_item_ptr(&path,
struct btrfs_file_extent_item);
if (extent->type == BTRFS_FILE_EXTENT_INLINE) {
btrfs_file_extent_item_to_cpu_inl(extent);
rd = btrfs_read_extent_inline(&path, extent, offset,
size, buf);
} else {
btrfs_file_extent_item_to_cpu(extent);
rd = btrfs_read_extent_reg(&path, extent, offset, size,
buf);
}
if (rd == -1ULL) {
printf("%s: Error reading extent\n", __func__);
rd_all = -1;
goto out;
}
offset = 0;
buf += rd;
rd_all += rd;
size -= rd;
if (!size)
break;
} while (!(res = btrfs_next_slot(&path)));
if (res)
return -1ULL;
out:
btrfs_free_path(&path);
return rd_all;
}