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authorJakob Unterwurzacher2016-02-06 19:27:59 +0100
committerJakob Unterwurzacher2016-02-06 19:27:59 +0100
commit9078a77850dd680bfa938d9ed7c83600a60c0e7b (patch)
tree03ee83879c398307d450002e1f07e928cb743672 /pathfs_frontend/write_lock.go
parent2b8cbd944149afe51fadddbd67ee4499d1d86250 (diff)
Move pathfs_frontend to internal/fusefrontend
"git status" for reference: renamed: pathfs_frontend/args.go -> internal/fusefrontend/args.go renamed: pathfs_frontend/compat_darwin.go -> internal/fusefrontend/compat_darwin.go renamed: pathfs_frontend/compat_linux.go -> internal/fusefrontend/compat_linux.go renamed: pathfs_frontend/file.go -> internal/fusefrontend/file.go renamed: pathfs_frontend/file_holes.go -> internal/fusefrontend/file_holes.go renamed: pathfs_frontend/fs.go -> internal/fusefrontend/fs.go renamed: pathfs_frontend/fs_dir.go -> internal/fusefrontend/fs_dir.go renamed: pathfs_frontend/names.go -> internal/fusefrontend/names.go renamed: pathfs_frontend/write_lock.go -> internal/fusefrontend/write_lock.go modified: main.go
Diffstat (limited to 'pathfs_frontend/write_lock.go')
-rw-r--r--pathfs_frontend/write_lock.go66
1 files changed, 0 insertions, 66 deletions
diff --git a/pathfs_frontend/write_lock.go b/pathfs_frontend/write_lock.go
deleted file mode 100644
index 0704eb6..0000000
--- a/pathfs_frontend/write_lock.go
+++ /dev/null
@@ -1,66 +0,0 @@
-package pathfs_frontend
-
-import (
- "sync"
-)
-
-func init() {
- wlock.m = make(map[uint64]*refCntMutex)
-}
-
-// wlock - serializes write accesses to each file (identified by inode number)
-// Writing partial blocks means we have to do read-modify-write cycles. We
-// really don't want concurrent writes there.
-// Concurrent full-block writes could actually be allowed, but are not to
-// keep the locking simple.
-var wlock wlockMap
-
-// wlockMap - usage:
-// 1) register
-// 2) lock ... unlock ...
-// 3) unregister
-type wlockMap struct {
- mapMutex sync.RWMutex
- m map[uint64]*refCntMutex
-}
-
-func (w *wlockMap) register(ino uint64) {
- w.mapMutex.Lock()
- r := w.m[ino]
- if r == nil {
- r = &refCntMutex{}
- w.m[ino] = r
- }
- r.refCnt++ // this must happen inside the mapMutex lock
- w.mapMutex.Unlock()
-}
-
-func (w *wlockMap) unregister(ino uint64) {
- w.mapMutex.Lock()
- r := w.m[ino]
- r.refCnt--
- if r.refCnt == 0 {
- delete(w.m, ino)
- }
- w.mapMutex.Unlock()
-}
-
-func (w *wlockMap) lock(ino uint64) {
- w.mapMutex.RLock()
- r := w.m[ino]
- w.mapMutex.RUnlock()
- r.Lock() // this can take a long time - execute outside the mapMutex lock
-}
-
-func (w *wlockMap) unlock(ino uint64) {
- w.mapMutex.RLock()
- r := w.m[ino]
- w.mapMutex.RUnlock()
- r.Unlock()
-}
-
-// refCntMutex - mutex with reference count
-type refCntMutex struct {
- sync.Mutex
- refCnt int
-}