Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

fix: directIO read size can exceeds buffer size #68

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

fix: directIO read size can exceeds buffer size #68

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 8 additions & 0 deletions mount_linux.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,9 +7,12 @@ import (
"net"
"os"
"os/exec"
"strconv"
"syscall"

"golang.org/x/sys/unix"

"github.com/jacobsa/fuse/internal/buffer"
)

func fusermount(dir string, cfg *MountConfig) (*os.File, error) {
Expand All @@ -29,6 +32,11 @@ func fusermount(dir string, cfg *MountConfig) (*os.File, error) {
// Start fusermount, passing it a buffer in which to write stderr.
var stderr bytes.Buffer

if cfg.Options == nil {
cfg.Options = make(map[string]string)
}
cfg.Options["max_read"] = strconv.Itoa(buffer.MaxReadSize)
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think you’ll need to ensure cfg.Options is non-nil here, see the travis test failure.

Copy link
Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks, I've made a modification. To reproduce the issue, just try to invoke a read system call with the size of 512Kbytes which is larger than MaxReadSize, and with O_DIRECT flag.

Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks for fixing this! Would it be possible to add a unit test, too, which exercises this behavior? It should fail before your fix commit, and pass afterwards, so that we don’t accidentally re-introduce this bug at some point down the road.

Copy link
Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Is there a guide on how to write ci test cases? I believe it is better to write a test case from user space file system. BTW, I have no idea why ci failed again.

Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Not sure I understand your question—there are no “ci test cases”, the CI just runs the go tests of this project :)

This particular failure might have been a flake (sometimes the CI is overloaded), so I have restarted the run.


cmd := exec.Command(
"fusermount",
"-o", cfg.toOptionsString(),
Expand Down