fastpath: Only allow IO to approved file types and file systems#238
Open
kurtmcmillan wants to merge 28 commits intodevelopfrom
Open
fastpath: Only allow IO to approved file types and file systems#238kurtmcmillan wants to merge 28 commits intodevelopfrom
kurtmcmillan wants to merge 28 commits intodevelopfrom
Conversation
Contributor
There was a problem hiding this comment.
Pull request overview
Updates the fastpath backend’s eligibility logic to only select fastpath I/O for regular files on ext4 (data=ordered) or xfs by default, with an environment-variable override to permit other filesystems.
Changes:
- Add
HIPFILE_UNSUPPORTED_FILESYSTEMSenvironment plumbing viaEnvironmentandConfiguration. - Update
Fastpath::score()to require a regular file and a supported filesystem (unless overridden). - Extend unit tests to cover the new configuration flag and fastpath filesystem/type gating behavior.
Reviewed changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 1 comment.
Show a summary per file
| File | Description |
|---|---|
src/amd_detail/backend/fastpath.cpp |
Enforces regular-file + supported-filesystem constraints in fastpath scoring. |
src/amd_detail/environment.h |
Adds the new env var constant and accessor declaration. |
src/amd_detail/environment.cpp |
Implements Environment::unsupported_filesystems() via existing bool parser. |
src/amd_detail/configuration.h |
Adds Configuration::unsupportedFilesystems() API. |
src/amd_detail/configuration.cpp |
Reads/caches HIPFILE_UNSUPPORTED_FILESYSTEMS into configuration. |
test/amd_detail/mconfiguration.h |
Extends configuration mock with unsupportedFilesystems(). |
test/amd_detail/configuration.cpp |
Adds tests verifying env var parsing/default behavior for unsupported filesystems flag. |
test/amd_detail/fastpath.cpp |
Updates/extends fastpath tests for mount info + regular file checks and override behavior. |
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
kurtmcmillan
force-pushed
the
kumcmill/add-ext4-xfs-check-to-fastpath-scoring
branch
2 times, most recently
from
e927ed3 to
abbeeb1
Compare
kurtmcmillan
changed the title
Contributor
There was a problem hiding this comment.
Pull request overview
Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
kurtmcmillan
force-pushed
the
kumcmill/add-ext4-xfs-check-to-fastpath-scoring
branch
from
abbeeb1 to
a9ea835
Compare
Contributor
There was a problem hiding this comment.
Pull request overview
Copilot reviewed 16 out of 16 changed files in this pull request and generated 5 comments.
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
kurtmcmillan
changed the title
kurtmcmillan
force-pushed
the
kumcmill/add-ext4-xfs-check-to-fastpath-scoring
branch
from
a9ea835 to
ad9b516
Compare
kurtmcmillan
requested review from
derobins,
gaoikawa,
jordan-turbofish,
riley-dixon and
zbyrne
as code owners
Contributor
There was a problem hiding this comment.
Pull request overview
Copilot reviewed 17 out of 17 changed files in this pull request and generated 2 comments.
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
zbyrne
approved these changes
Mar 30, 2026
The necessary data from the statx struct is now cached in File.
The mount information the fastpath needs can now be obtained from File::onXfs() and File::onExt4Ordered().
At one time this was used to determine if O_DIRECT was set on File's file descriptor. File now holds buffered (~O_DIRECT) and unbuffered (O_DIRECT) file descriptors. Clients can use the file descriptor that best suits their purpose.
…::score expectations This will reduce the blast radius of the following changes.
This will be used by the to determine if IO to unsupported file systems should be permitted to use the fastpath backend.
… checks in Fastpath::score If HIPFILE_UNSUPPORTED_FILE_SYSTEMS=true, Fastpath::score will accept IO to regular files on any filesystem.
kurtmcmillan
force-pushed
the
kumcmill/add-ext4-xfs-check-to-fastpath-scoring
branch
from
ad9b516 to
192215b
Compare
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Motivation
Currently, hipFile has only been tested with block devices and regular files on ext4(ordered) or xfs file systems. This change updates
Fastpath::score()to accept IO operations that target block devices or files backed by ext4(ordered) or xfs.Technical Details
When a file is registered, hipFile will cache file type and mount information.
Fastpath::score()will use the cached information to determine if it will accept an IO.If
HIPFILE_UNSUPPORTED_FILE_SYSTEMS=trueis set in the environment, thenFastpath::scorewill allow IO to regular files on unsupported filesystems.AIHIPFILE-114