u-boot/fs/btrfs/super.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

232 lines
5.9 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"
#define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN \
| BTRFS_HEADER_FLAG_RELOC \
| BTRFS_SUPER_FLAG_ERROR \
| BTRFS_SUPER_FLAG_SEEDING \
| BTRFS_SUPER_FLAG_METADUMP)
#define BTRFS_SUPER_INFO_SIZE 4096
static int btrfs_newest_root_backup(struct btrfs_super_block *sb)
{
struct btrfs_root_backup *root_backup;
int i, newest = -1;
for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; ++i) {
root_backup = sb->super_roots + i;
if (root_backup->tree_root_gen == sb->generation)
newest = i;
}
return newest;
}
static inline int is_power_of_2(u64 x)
{
return !(x & (x - 1));
}
static int btrfs_check_super_csum(char *raw_disk_sb)
{
struct btrfs_super_block *disk_sb =
(struct btrfs_super_block *) raw_disk_sb;
u16 csum_type = le16_to_cpu(disk_sb->csum_type);
if (csum_type == BTRFS_CSUM_TYPE_CRC32) {
u32 crc = ~(u32) 0;
const int csum_size = sizeof(crc);
char result[csum_size];
crc = btrfs_csum_data(raw_disk_sb + BTRFS_CSUM_SIZE, crc,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, result);
if (memcmp(raw_disk_sb, result, csum_size))
return -1;
} else {
return -1;
}
return 0;
}
static int btrfs_check_super(struct btrfs_super_block *sb)
{
int ret = 0;
if (sb->flags & ~BTRFS_SUPER_FLAG_SUPP) {
printf("%s: Unsupported flags: %llu\n", __func__,
sb->flags & ~BTRFS_SUPER_FLAG_SUPP);
}
if (sb->root_level > BTRFS_MAX_LEVEL) {
printf("%s: tree_root level too big: %d >= %d\n", __func__,
sb->root_level, BTRFS_MAX_LEVEL);
ret = -1;
}
if (sb->chunk_root_level > BTRFS_MAX_LEVEL) {
printf("%s: chunk_root level too big: %d >= %d\n", __func__,
sb->chunk_root_level, BTRFS_MAX_LEVEL);
ret = -1;
}
if (sb->log_root_level > BTRFS_MAX_LEVEL) {
printf("%s: log_root level too big: %d >= %d\n", __func__,
sb->log_root_level, BTRFS_MAX_LEVEL);
ret = -1;
}
if (!is_power_of_2(sb->sectorsize) || sb->sectorsize < 4096 ||
sb->sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
printf("%s: invalid sectorsize %u\n", __func__,
sb->sectorsize);
ret = -1;
}
if (!is_power_of_2(sb->nodesize) || sb->nodesize < sb->sectorsize ||
sb->nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
printf("%s: invalid nodesize %u\n", __func__, sb->nodesize);
ret = -1;
}
if (sb->nodesize != sb->__unused_leafsize) {
printf("%s: invalid leafsize %u, should be %u\n", __func__,
sb->__unused_leafsize, sb->nodesize);
ret = -1;
}
if (!IS_ALIGNED(sb->root, sb->sectorsize)) {
printf("%s: tree_root block unaligned: %llu\n", __func__,
sb->root);
ret = -1;
}
if (!IS_ALIGNED(sb->chunk_root, sb->sectorsize)) {
printf("%s: chunk_root block unaligned: %llu\n", __func__,
sb->chunk_root);
ret = -1;
}
if (!IS_ALIGNED(sb->log_root, sb->sectorsize)) {
printf("%s: log_root block unaligned: %llu\n", __func__,
sb->log_root);
ret = -1;
}
if (memcmp(sb->fsid, sb->dev_item.fsid, BTRFS_UUID_SIZE) != 0) {
printf("%s: dev_item UUID does not match fsid\n", __func__);
ret = -1;
}
if (sb->bytes_used < 6*sb->nodesize) {
printf("%s: bytes_used is too small %llu\n", __func__,
sb->bytes_used);
ret = -1;
}
if (!is_power_of_2(sb->stripesize)) {
printf("%s: invalid stripesize %u\n", __func__, sb->stripesize);
ret = -1;
}
if (sb->sys_chunk_array_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
printf("%s: system chunk array too big %u > %u\n", __func__,
sb->sys_chunk_array_size, BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
ret = -1;
}
if (sb->sys_chunk_array_size < sizeof(struct btrfs_key) +
sizeof(struct btrfs_chunk)) {
printf("%s: system chunk array too small %u < %zu\n", __func__,
sb->sys_chunk_array_size, sizeof(struct btrfs_key)
+ sizeof(struct btrfs_chunk));
ret = -1;
}
return ret;
}
int btrfs_read_superblock(void)
{
const u64 superblock_offsets[4] = {
0x10000ull,
0x4000000ull,
0x4000000000ull,
0x4000000000000ull
};
char raw_sb[BTRFS_SUPER_INFO_SIZE];
struct btrfs_super_block *sb = (struct btrfs_super_block *) raw_sb;
u64 dev_total_bytes;
int i, root_backup_idx;
dev_total_bytes = (u64) btrfs_part_info->size * btrfs_part_info->blksz;
btrfs_info.sb.generation = 0;
for (i = 0; i < 4; ++i) {
if (superblock_offsets[i] + sizeof(sb) > dev_total_bytes)
break;
if (!btrfs_devread(superblock_offsets[i], BTRFS_SUPER_INFO_SIZE,
raw_sb))
break;
if (btrfs_check_super_csum(raw_sb)) {
printf("%s: invalid checksum at superblock mirror %i\n",
__func__, i);
continue;
}
btrfs_super_block_to_cpu(sb);
if (sb->magic != BTRFS_MAGIC) {
printf("%s: invalid BTRFS magic 0x%016llX at "
"superblock mirror %i\n", __func__, sb->magic,
i);
} else if (sb->bytenr != superblock_offsets[i]) {
printf("%s: invalid bytenr 0x%016llX (expected "
"0x%016llX) at superblock mirror %i\n",
__func__, sb->bytenr, superblock_offsets[i], i);
} else if (btrfs_check_super(sb)) {
printf("%s: Checking superblock mirror %i failed\n",
__func__, i);
} else if (sb->generation > btrfs_info.sb.generation) {
memcpy(&btrfs_info.sb, sb, sizeof(*sb));
} else {
/* Nothing */
}
}
if (!btrfs_info.sb.generation) {
printf("%s: No valid BTRFS superblock found!\n", __func__);
return -1;
}
root_backup_idx = btrfs_newest_root_backup(&btrfs_info.sb);
if (root_backup_idx < 0) {
printf("%s: No valid root_backup found!\n", __func__);
return -1;
}
btrfs_info.root_backup = btrfs_info.sb.super_roots + root_backup_idx;
if (btrfs_info.root_backup->num_devices != 1) {
printf("%s: Unsupported number of devices (%lli). This driver "
"only supports filesystem on one device.\n", __func__,
btrfs_info.root_backup->num_devices);
return -1;
}
debug("Chosen superblock with generation = %llu\n",
btrfs_info.sb.generation);
return 0;
}