From a2956163267e253f614dd2d6d8151614b9b0dc77 Mon Sep 17 00:00:00 2001 From: Michael Pratt Date: Tue, 15 Oct 2019 09:59:59 -0700 Subject: Make Attach no longer a special snowflake fsgofer.attachPoint.Attach has a bunch of funky special logic to create a RW file or connect a socket rather than creating a standard control file like localFile.Walk. This is unecessary and error-prone, as the attach point still has to go through Open or Connect which will properly convert the control file to something usable. As such, switch the logic to be equivalent to a simple Walk. Updates #235 PiperOrigin-RevId: 274827872 --- runsc/fsgofer/fsgofer.go | 55 +++++++++++------------------------------------- 1 file changed, 12 insertions(+), 43 deletions(-) (limited to 'runsc') diff --git a/runsc/fsgofer/fsgofer.go b/runsc/fsgofer/fsgofer.go index 29a82138e..ed8b02cf0 100644 --- a/runsc/fsgofer/fsgofer.go +++ b/runsc/fsgofer/fsgofer.go @@ -21,7 +21,6 @@ package fsgofer import ( - "errors" "fmt" "io" "math" @@ -126,13 +125,6 @@ func NewAttachPoint(prefix string, c Config) (p9.Attacher, error) { // Attach implements p9.Attacher. func (a *attachPoint) Attach() (p9.File, error) { - // dirFD (1st argument) is ignored because 'prefix' is always absolute. - stat, err := statAt(-1, a.prefix) - if err != nil { - return nil, fmt.Errorf("stat file %q, err: %v", a.prefix, err) - } - - // Acquire the attach point lock. a.attachedMu.Lock() defer a.attachedMu.Unlock() @@ -140,47 +132,24 @@ func (a *attachPoint) Attach() (p9.File, error) { return nil, fmt.Errorf("attach point already attached, prefix: %s", a.prefix) } - // Hold the file descriptor we are converting into a p9.File. - var f *fd.FD - - // Apply the S_IFMT bitmask so we can detect file type appropriately. - switch fmtStat := stat.Mode & syscall.S_IFMT; fmtStat { - case syscall.S_IFSOCK: - // Check to see if the CLI option has been set to allow the UDS mount. - if !a.conf.HostUDS { - return nil, errors.New("host UDS support is disabled") - } - - // Attempt to open a connection. Bubble up the failures. - f, err = fd.DialUnix(a.prefix) - if err != nil { - return nil, err - } - - default: - // Default to Read/Write permissions. - mode := syscall.O_RDWR - - // If the configuration is Read Only or the mount point is a directory, - // set the mode to Read Only. - if a.conf.ROMount || fmtStat == syscall.S_IFDIR { - mode = syscall.O_RDONLY - } + f, err := openAnyFile(a.prefix, func(mode int) (*fd.FD, error) { + return fd.Open(a.prefix, openFlags|mode, 0) + }) + if err != nil { + return nil, fmt.Errorf("unable to open %q: %v", a.prefix, err) + } - // Open the mount point & capture the FD. - f, err = fd.Open(a.prefix, openFlags|mode, 0) - if err != nil { - return nil, fmt.Errorf("unable to open file %q, err: %v", a.prefix, err) - } + stat, err := stat(f.FD()) + if err != nil { + return nil, fmt.Errorf("unable to stat %q: %v", a.prefix, err) } - // Return a localFile object to the caller with the UDS FD included. - rv, err := newLocalFile(a, f, a.prefix, stat) + lf, err := newLocalFile(a, f, a.prefix, stat) if err != nil { - return nil, err + return nil, fmt.Errorf("unable to create localFile %q: %v", a.prefix, err) } a.attached = true - return rv, nil + return lf, nil } // makeQID returns a unique QID for the given stat buffer. -- cgit v1.2.3