Cleanup of deprecated functions + Behavioral Clarifications #307
+275
−819
Commits on Nov 13, 2024
-
fix: move .cargo/config to .cargo/config.toml
This fixes a cargo warning printed in recent toolchains. Since we do not support toolchains older than 1.38, there is no need to symlink to the new file to the old one. Signed-off-by: Patrick Roy <[email protected]>
-
fix: remove superfluous calls to
.subslicein io.rsThe call to `.subslice()` ensures that the range `[0, total]` is a valid subslice of the `buf: VolatileSlice` passed in. But `total = min(buf.len(), self.len()) <= buf.len()`, and thus `[0, total]` is definitely a valid subslice of `buf`. The `copy_{from,to}_volatile_slice` functions do not actually care about the length of the `VolatileSlice` passed in - it relies on the safety invariant to ensure that the passed slice has length at least `total`. Thus it doesn't matter if we pass a slice of length `total`, or of a length greater than `total`. It will simply access the first `total` bytes in the slice. Also clarify the safety comment, as some slightly mistakes seemingly snuck in when copying them. Signed-off-by: Patrick Roy <[email protected]> -
Clarify behavior of
VolatileMemory::compute_end_offsetFix the doc comment, and add a unit test for this functions. Particularly the "allow length 0 accesses at the end of the slice" behavior was undocumented before. Signed-off-by: Patrick Roy <[email protected]>
-
Drop assert from
read/write_volatileinGuestMemoryThe comment on the assertion was wrong, as we are not even doing anything unsafe in the first place. Additionally, the `offset` variable is unused by these functions, so the assertion is at best a sanity check that the `try_access` implementation is correct, although I don't particularly see the value of that. Remove the assertion to prevent confusion. Signed-off-by: Patrick Roy <[email protected]>
-
Implement
VolatileMemory::get_slicein terms ofsubsliceThe two functions contain exactly the same body, so just have one call the other. No functional change intended. Signed-off-by: Patrick Roy <[email protected]>
-
add
retry_eintr!utility macroAdd a macro that automatically retries a given I/O operation if EINTR is returned. This is a fairly common pattern in vm-memory. Signed-off-by: Patrick Roy <[email protected]>
-
Introduce
VolatileSlice::truncateThis function reduces the length of a volatile slice. Many of the I/O primitives rely on volatile slice lengths to determine how many bytes should be read/written, and in cases where we want to read/write "up to X bytes", calling `.truncate` is needed. Signed-off-by: Patrick Roy <[email protected]>
-
chore: remove deprecated methods
The old `Read`/`Write` based APIs for operating on guest memory have been deprecated for a fairly long time now, and are superseceded by their `ReadVolatile`/`WriteVolatile` equivalents. The `fold` and friends functions have been deprecated for way longer. Various `.as_ptr` APIs in volatile_memory.rs are deprecated in favor of pointer guards. Let's clean up the crate and remove all of these. Signed-off-by: Patrick Roy <[email protected]>
-
fix: move volatile memory access methods to
BytestraitThe `read_[exact_]_volatile_from` and `write_[all_]volatile_to` functions were intended to be replacements for their `Read` and `Write` based counterparts. However, those used to live in the `Bytes` trait, not the `GuestMemory` trait. Fix up this goof on my part by moving them to the `Bytes` trait. Signed-off-by: Patrick Roy <[email protected]>
-
doc: clarify behavior of
Bytes::readand coCapture the actual behavior of various edge cases around empty buffers and containers in the doc comment. Signed-off-by: Patrick Roy <[email protected]>
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.