wip: Dokan file lock/unlock

src/dokan/ceph_dokan.cc

@@ -847,6 +847,122 @@ static NTSTATUS WinCephUnmount(
   return 0;
 }
 
+static NTSTATUS WinCephLockFile(
+  LPCWSTR FileName,
+  LONGLONG ByteOffset,
+  LONGLONG Length,
+  PDOKAN_FILE_INFO DokanFileInfo) {
+  if (!Length) {
+    return 0;
+  }
+
+  std::string path = get_path(FileName);
+
+  if (ByteOffset < 0) {
+    dout(2) << __func__ << " " << path
+            << ": Invalid offset: " << ByteOffset << dendl;
+    return STATUS_INVALID_PARAMETER;
+  }
+  if (ByteOffset > CEPH_DOKAN_MAX_FILE_SZ ||
+      Length > CEPH_DOKAN_MAX_IO_SZ) {
+    dout(2) << "Lock size exceeds max file length: " << path
+            << ". ByteOffset: " << ByteOffset
+            << ". Lock length: " << Length << dendl;
+    return STATUS_FILE_TOO_LARGE;
+  }
+
+  pfd_context fdc = (pfd_context) &(DokanFileInfo->Context);
+  if (!fdc->fd) {
+    dout(15) << __func__ << " " << get_path(FileName)
+             << ". Missing context, using temporary handle." << dendl;
+
+    string path = get_path(FileName);
+    int fd_new = ceph_open(cmount, path.c_str(), O_RDONLY, 0);
+    if (fd_new < 0) {
+      dout(2) << __func__ << " " << path
+              << ": ceph_open failed. Error: " << fd_new << dendl;
+      return cephfs_errno_to_ntstatus_map(fd_new);
+    }
+
+    int ret = ceph_flock(cmount, fd_new, LOCK_EX | LOCK_NB, pthread_self());
+    if (ret < 0) {
+      dout(2) << __func__ << " " << path
+              << ": ceph_flock lock failed. Error: " << ret
+              << ". Path: " << path << dendl;
+      ceph_close(cmount, fd_new);
+      return cephfs_errno_to_ntstatus_map(ret);
+    }
+    ceph_close(cmount, fd_new);
+    return 0;
+  } else {
+    int ret = ceph_flock(cmount, fdc->fd, LOCK_EX | LOCK_NB, pthread_self());
+    if (ret < 0) {
+      dout(2) << __func__ << " " << path
+              << ": ceph_flock lock failed. Error: " << ret
+              << ". Path: " << path << dendl;
+      return cephfs_errno_to_ntstatus_map(ret);
+    }
+    return 0;
+  }
+}
+
+static NTSTATUS WinCephUnlockFile(
+  LPCWSTR FileName,
+  LONGLONG ByteOffset,
+  LONGLONG Length,
+  PDOKAN_FILE_INFO DokanFileInfo) {
+
+  std::string path = get_path(FileName);
+
+  if (ByteOffset < 0) {
+    dout(2) << __func__ << " " << path
+            << ": Invalid offset: " << ByteOffset << dendl;
+    return STATUS_INVALID_PARAMETER;
+  }
+  if (ByteOffset > CEPH_DOKAN_MAX_FILE_SZ ||
+      Length > CEPH_DOKAN_MAX_IO_SZ) {
+    dout(2) << "Lock size exceeds max file length: " << path
+            << ". ByteOffset: " << ByteOffset
+            << ". Lock length: " << Length << dendl;
+    return STATUS_FILE_TOO_LARGE;
+  }
+
+  pfd_context fdc = (pfd_context) &(DokanFileInfo->Context);
+  if (!fdc->fd) {
+    dout(15) << __func__ << " " << get_path(FileName)
+             << ". Missing context, using temporary handle." << dendl;
+
+    string path = get_path(FileName);
+    int fd_new = ceph_open(cmount, path.c_str(), O_RDONLY, 0);
+    if (fd_new < 0) {
+      dout(2) << __func__ << " " << path
+              << ": ceph_open failed. Error: " << fd_new << dendl;
+      return cephfs_errno_to_ntstatus_map(fd_new);
+    }
+
+    int ret = ceph_flock(cmount, fd_new, LOCK_UN, pthread_self());
+    if (ret < 0) {
+      dout(2) << __func__ << " " << path
+              << ": ceph_flock unlock failed. Error: " << ret
+              << ". Path: " << path << dendl;
+      ceph_close(cmount, fd_new);
+      return cephfs_errno_to_ntstatus_map(ret);
+    }
+    ceph_close(cmount, fd_new);
+    return 0;
+  } else {
+    int ret = ceph_flock(cmount, fdc->fd, LOCK_UN, pthread_self());
+
+    if (ret < 0) {
+      dout(2) << __func__ << " " << path
+              << ": ceph_flock unlock failed. Error: " << ret
+              << ". Path: " << path << dendl;
+      return cephfs_errno_to_ntstatus_map(ret);
+    }
+    return 0;
+  }
+}
+
 BOOL WINAPI ConsoleHandler(DWORD dwType)
 {
   switch(dwType) {
@@ -926,6 +1042,8 @@ int do_map() {
   dokan_operations->GetDiskFreeSpace = WinCephGetDiskFreeSpace;
   dokan_operations->GetVolumeInformation = WinCephGetVolumeInformation;
   dokan_operations->Unmounted = WinCephUnmount;
+  dokan_operations->LockFile = WinCephLockFile;
+  dokan_operations->UnlockFile = WinCephUnlockFile;
 
   ceph_create_with_context(&cmount, g_ceph_context);
 

src/dokan/ceph_dokan.h

@@ -25,6 +25,7 @@ struct Config {
   bool current_session_only = false;
   bool debug = false;
   bool dokan_stderr = false;
+  bool enable_cephfs_locks = false;
 
   int operation_timeout = CEPH_DOKAN_IO_DEFAULT_TIMEOUT;
 

src/dokan/options.cc

@@ -33,6 +33,7 @@ Map options:
 
   --debug                     enable debug output
   --dokan-stderr              enable stderr Dokan logging
+  --enable-cephfs-locks       enable cephfs file locks
 
   --read-only                 read-only mount
   -o [ --win-mount-mgr]       use the Windows mount manager
@@ -111,6 +112,8 @@ int parse_args(
       cfg->removable = true;
     } else if (ceph_argparse_flag(args, i, "--win-mount-mgr", "-o", (char *)NULL)) {
       cfg->use_win_mount_mgr = true;
+    } else if (ceph_argparse_flag(args, i, "--enable-cephfs-locks", (char *)NULL)) {
+      cfg->enable_cephfs_locks = true;
     } else if (ceph_argparse_witharg(args, i, &win_vol_name,
                                      "--win-vol-name", (char *)NULL)) {
       cfg->win_vol_name = to_wstring(win_vol_name);
@@ -221,6 +224,8 @@ int set_dokan_options(Config *cfg, PDOKAN_OPTIONS dokan_options) {
     dokan_options->Options |= DOKAN_OPTION_DEBUG;
   if (cfg->dokan_stderr)
     dokan_options->Options |= DOKAN_OPTION_STDERR;
+  if (cfg->enable_cephfs_locks)
+    dokan_options->Options |= DOKAN_OPTION_FILELOCK_USER_MODE;
 
   return 0;
 }