checkpoint

src/func_open_create_utils.cpp

@@ -0,0 +1,122 @@
+/*
+  ISC License
+
+  Copyright (c) 2024, Antonio SJ Musumeci <trapexit@spawn.link>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "func_open_create_utils.hpp"
+
+#include "procfs_get_name.hpp"
+
+/*
+  The kernel expects being able to issue read requests when running
+  with writeback caching enabled so we must change O_WRONLY to
+  O_RDWR.
+
+  With writeback caching enabled the kernel handles O_APPEND. Could
+  be an issue if the underlying file changes out of band but that is
+  true of any caching.
+*/
+void
+utils::tweak_flags_writeback_cache(int *flags_)
+{
+  if((*flags_ & O_ACCMODE) == O_WRONLY)
+    *flags_ = ((*flags_ & ~O_ACCMODE) | O_RDWR);
+  if(*flags_ & O_APPEND)
+    *flags_ &= ~O_APPEND;
+}
+
+namespace l
+{
+  static
+  bool
+  rdonly(const int flags_)
+  {
+    return ((flags_ & O_ACCMODE) == O_RDONLY);
+  }
+}
+
+bool
+utils::calculate_flush(FlushOnClose flushonclose_,
+                       int const    flags_)
+{
+  switch(flushonclose_)
+    {
+    case FlushOnCloseEnum::NEVER:
+      return false;
+    case FlushOnCloseEnum::OPENED_FOR_WRITE:
+      return !l::rdonly(flags_);
+    case FlushOnCloseEnum::ALWAYS:
+      return true;
+    }
+
+  return true;
+}
+
+
+void
+utils::cfg_to_ffi_flags(Config::Read     &cfg_,
+                        int const         tid_,
+                        fuse_file_info_t *ffi_)
+{
+  switch(cfg_->cache_files)
+    {
+    case CacheFiles::ENUM::LIBFUSE:
+      ffi_->direct_io  = cfg_->direct_io;
+      ffi_->keep_cache = cfg_->kernel_cache;
+      ffi_->auto_cache = cfg_->auto_cache;
+      break;
+    case CacheFiles::ENUM::OFF:
+      ffi_->direct_io  = 1;
+      ffi_->keep_cache = 0;
+      ffi_->auto_cache = 0;
+      break;
+    case CacheFiles::ENUM::PARTIAL:
+      ffi_->direct_io  = 0;
+      ffi_->keep_cache = 0;
+      ffi_->auto_cache = 0;
+      break;
+    case CacheFiles::ENUM::FULL:
+      ffi_->direct_io  = 0;
+      ffi_->keep_cache = 1;
+      ffi_->auto_cache = 0;
+      break;
+    case CacheFiles::ENUM::AUTO_FULL:
+      ffi_->direct_io  = 0;
+      ffi_->keep_cache = 0;
+      ffi_->auto_cache = 1;
+      break;
+    case CacheFiles::ENUM::PER_PROCESS:
+      std::string proc_name;
+
+      proc_name = procfs::get_name(tid_);
+      if(cfg_->cache_files_process_names.count(proc_name) == 0)
+        {
+          ffi_->direct_io  = 1;
+          ffi_->keep_cache = 0;
+          ffi_->auto_cache = 0;
+        }
+      else
+        {
+          ffi_->direct_io  = 0;
+          ffi_->keep_cache = 0;
+          ffi_->auto_cache = 0;
+        }
+      break;
+    }
+
+  if(cfg_->parallel_direct_writes == true)
+    ffi_->parallel_direct_writes = ffi_->direct_io;
+}

src/func_open_create_utils.hpp

@@ -0,0 +1,30 @@
+/*
+  ISC License
+
+  Copyright (c) 2024, Antonio SJ Musumeci <trapexit@spawn.link>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#pragma once
+
+#include "config.hpp"
+
+#include "fuse.h"
+
+namespace utils
+{
+  void tweak_flags_writeback_cache(int *flags);
+  bool calculate_flush(FlushOnClose flushonclose, int const flags);
+  void cfg_to_ffi_flags(Config::Read &cfg, int const tid, fuse_file_info_t *ffi);
+}