diff options
author | Ryan Ofsky <ryan@ofsky.org> | 2023-09-29 12:50:15 -0400 |
---|---|---|
committer | Ryan Ofsky <ryan@ofsky.org> | 2023-09-29 13:29:51 -0400 |
commit | f562856d02d60625d914012d38df3582ea6b6c1f (patch) | |
tree | ddcdb2660ac463c5225a33ab01775fb06b74dcdf /src/validation.cpp | |
parent | d18a8f6f6969487021b8fd50391a2a8d1dc29844 (diff) | |
parent | d8041d4e042957660827313951b18c8dd9a99a16 (diff) | |
download | bitcoin-f562856d02d60625d914012d38df3582ea6b6c1f.tar.xz |
Merge bitcoin/bitcoin#27866: blockstorage: Return on fatal flush errors
d8041d4e042957660827313951b18c8dd9a99a16 blockstorage: Return on fatal undo file flush error (TheCharlatan)
f0207e00303a1030eca795ede231e3c0d94df061 blockstorage: Return on fatal block file flush error (TheCharlatan)
5671c15f4520c6dc20e0805fd0b06157ff94bcd7 blockstorage: Mark FindBlockPos as nodiscard (TheCharlatan)
Pull request description:
The goal of this PR is to establish that fatal blockstorage flush errors should be treated as errors at their call site.
Prior to this patch `FlushBlockFile` may have failed without returning in `Chainstate::FlushStateToDisk`, leading to a potential write from `WriteBlockIndexDB` that may refer to a block that is not fully flushed to disk yet. By returning if either `FlushUndoFile` or `FlushBlockFile` fail, we ensure that no further write operations take place that may lead to an inconsistent database when crashing. Add `[[nodiscard]]` annotations to them such that they are not ignored in future.
Functions that call either `FlushUndoFile` or `FlushBlockFile`, need to handle these extra abort cases properly. Since `Chainstate::FlushStateToDisk` already produces an abort error in case of `WriteBlockIndexDB` failing, no extra logic for functions calling `Chainstate::FlushStateToDisk` is required.
Besides `Chainstate::FlushStateToDisk`, `FlushBlockFile` is also called by `FindBlockPos`, while `FlushUndoFile` is only called by `FlushBlockFile` and `WriteUndoDataForBlock`. For both these cases, the flush error is not further bubbled up. Instead, the error is logged and a comment is provided why bubbling up an error would be less desirable in these cases.
---
This pull request is part of a larger effort towards improving the shutdown / abort / fatal error handling in validation code. It is a first step towards implementing proper fatal error return type enforcement similar as proposed by theuni in this pull request [comment](https://github.com/bitcoin/bitcoin/pull/27711#issuecomment-1563561502). For ease of review of these critical changes, a first step would be checking that `AbortNode` leads to early and error-conveying returns at its call site. Further work for enforcing returns when `AbortNode` is called is done in https://github.com/bitcoin/bitcoin/pull/27862.
ACKs for top commit:
stickies-v:
re-ACK d8041d4
ryanofsky:
Code review ACK d8041d4e042957660827313951b18c8dd9a99a16
Tree-SHA512: 47ade9b873b15e567c8f60ca538d5a0daf32163e1031be3212a3a45eb492b866664b225f2787c9e40f3e0c089140157d8fd1039abc00c7bdfeec1b52ecd7e219
Diffstat (limited to 'src/validation.cpp')
-rw-r--r-- | src/validation.cpp | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/src/validation.cpp b/src/validation.cpp index 4acd5c7cb0..357b4d422d 100644 --- a/src/validation.cpp +++ b/src/validation.cpp @@ -2594,7 +2594,11 @@ bool Chainstate::FlushStateToDisk( LOG_TIME_MILLIS_WITH_CATEGORY("write block and undo data to disk", BCLog::BENCH); // First make sure all block and undo data is flushed to disk. - m_blockman.FlushBlockFile(); + // TODO: Handle return error, or add detailed comment why it is + // safe to not return an error upon failure. + if (!m_blockman.FlushBlockFile()) { + LogPrintLevel(BCLog::VALIDATION, BCLog::Level::Warning, "%s: Failed to flush block file.\n", __func__); + } } // Then update all block file information (which may refer to block and undo files). |