This patchset adds fault injection support for btrfs_data_csum_ok,
enabling controlled simulation of checksum mismatches to test btrfs
silent data corruption detection and reporting paths.

The first patch extends the error injection framework with a new type,
EI_ETYPE_FALSE, which allows bool-returning functions to be overridden
with a false return value directly.

The second patch marks btrfs_data_csum_ok with ALLOW_ERROR_INJECTION
using this new type.

The third patch adds a parent field to fei_attr to allow fault injection
on a function only when called from a specific parent function. 

Song Chen (3):
  error-injection: Introduce EI_ETYPE_FALSE for fail_function
  btrfs: Allow error injection on btrfs_data_csum_ok
  error-injection: Introduce parent in fei_attr

 arch/arm/lib/error-inject.c           |  6 ++
 arch/arm64/lib/error-inject.c         |  6 ++
 arch/csky/lib/error-inject.c          |  6 ++
 arch/loongarch/lib/error-inject.c     |  6 ++
 arch/powerpc/lib/error-inject.c       |  6 ++
 arch/riscv/lib/error-inject.c         |  6 ++
 arch/s390/lib/error-inject.c          |  6 ++
 arch/x86/lib/error-inject.c           |  6 ++
 fs/btrfs/inode.c                      |  1 +
 include/asm-generic/error-injection.h |  6 ++
 kernel/fail_function.c                | 98 ++++++++++++++++++++++++++-
 11 files changed, 152 insertions(+), 1 deletion(-)

---
changelog:
v1 --- v2:
Add a parent field to struct fei_attr.

-- 
2.43.0