af6f301834
[BUG]
There is a bug report that on s390x big endian systems, mkfs.btrfs just
fails:
$ mkfs.btrfs -f ~/test.img
btrfs-progs v6.3.1
Invalid mapping for 1081344-1097728, got 17592186044416-17592190238720
Couldn't map the block 1081344
ERROR: cannot read chunk root
ERROR: open ctree failed
[CAUSE]
The error is caused by wrong endian conversion. The s390x is a big
endian architecture:
$ lscpu
Byte Order: Big Endian
While checking the offending @disk_key and @key inside
btrfs_read_sys_array(), we got:
2301 while (cur_offset < array_size) {
(gdb)
2304 if (cur_offset + len > array_size)
(gdb)
2307 btrfs_disk_key_to_cpu(&key, disk_key);
(gdb)
2310 sb_array_offset += len;
(gdb) print *disk_key
$2 = {objectid = 281474976710656, type = 228 '\344', offset = 17592186044416}
(gdb) print key
$3 = {objectid = 281474976710656, type = 228 '\344', offset = 17592186044416}
(gdb)
Now we can see, @disk_key is indeed in the little endian, but @key is
not converted to the CPU native endian.
Furthermore, if we step into the help btrfs_disk_key_to_cpu(), it shows
we're using little endian version:
(gdb) step
btrfs_disk_key_to_cpu (disk_key=0x109fcdb, cpu_key=0x3ffffff847f)
at ./kernel-shared/accessors.h:592
592 memcpy(cpu_key, disk_key, sizeof(struct btrfs_key));
[FIX]
The kernel accessors.h checks if __LITTLE_ENDIAN is defined or not, but
that only works inside kernel.
In user space, __LITTLE_ENDIAN and __BIG_ENDIAN are both provided by
kerncompat.h that should have been included already.
Instead we should check __BYTE_ORDER against __LITTLE_ENDIAN to
determine our endianness.
With this change, s390x build works as expected now.
Issue: #639
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
||
|---|---|---|
| .. | ||
| uapi | ||
| README.md | ||
| accessors.c | ||
| accessors.h | ||
| async-thread.c | ||
| async-thread.h | ||
| backref.c | ||
| backref.h | ||
| compression.h | ||
| ctree.c | ||
| ctree.h | ||
| delayed-ref.c | ||
| delayed-ref.h | ||
| dir-item.c | ||
| disk-io.c | ||
| disk-io.h | ||
| extent-io-tree.c | ||
| extent-io-tree.h | ||
| extent-tree.c | ||
| extent_io.c | ||
| extent_io.h | ||
| file-item.c | ||
| file-item.h | ||
| file.c | ||
| free-space-cache.c | ||
| free-space-cache.h | ||
| free-space-tree.c | ||
| free-space-tree.h | ||
| inode-item.c | ||
| inode.c | ||
| locking.c | ||
| locking.h | ||
| messages.c | ||
| messages.h | ||
| misc.h | ||
| print-tree.c | ||
| print-tree.h | ||
| root-tree.c | ||
| send.h | ||
| transaction.c | ||
| transaction.h | ||
| tree-checker.c | ||
| tree-checker.h | ||
| tree-mod-log.h | ||
| ulist.c | ||
| ulist.h | ||
| uuid-tree.c | ||
| volumes.c | ||
| volumes.h | ||
| zoned.c | ||
| zoned.h | ||
README.md
Shared sources with kernel
Status and progress of kernel/userspace synchronization.
- accessors.c - done, local changes
- accessors.h - done, local changes
- async-thread.c - done
- async-thread.h - done
- backref.c - todo
- backref.h - todo
- compression.h - done
- ctree.c - partial
- ctree.h - partial
- delayed-ref.c - partial
- delayed-ref.h - partial
- dir-item.c - partial
- disk-io.c - todo
- disk-io.h - todo
- extent_io.c
- extent_io.h
- extent-io-tree.c - done, local changes
- extent-io-tree.h - done, local changes
- extent-tree.c - todo
- file.c - todo
- file-item.c - todo
- file-item.h - partial
- free-space-cache.c - not needed
- free-space-cache.h - not needed
- free-space-tree.c - partial
- free-space-tree.h - partial
- inode.c - todo
- inode-item.c - partial
- locking.c - done, local changes
- locking.h - done, local changes
- messages.c - done, local changes
- messages.h - done, local changes
- misc.h - done
- print-tree.c - partial, sync to kernel
- print-tree.h - partial
- root-tree.c - partial
- root-tree.h - done
- send.h - done
- transaction.c - todo
- transaction.h - partial, local changes
- tree-checker.c - partial, local changes
- tree-checker.h - partial, local changes
- tree-mod-log.h - done, local changes
- ulist.c - done
- ulist.h - done
- uuid-tree.c - partial
- volumes.c - todo, local changes
- volumes.h - todo, local changes
- zoned.c - todo
- zoned.h - todo