ACPI tables translator

Exposes x86 ACPI tables as a netfs on a mount point

* acpi: New directory.
* Makefile (prog-subdirs): Add acpi.
* hurd/hurd_types.h (FSTYPE_ACPI): New macro.

1 files changed, 147 insertions, 0 deletions

diff --git a/acpi/acpifs.h b/acpi/acpifs.h
new file mode 100644
index 00000000..2e9063cc
--- /dev/null
+++ b/acpi/acpifs.h
@@ -0,0 +1,147 @@
+/*
+   Copyright (C) 2018 Free Software Foundation, Inc.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   The GNU Hurd is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with the GNU Hurd.  If not, see <<a rel="nofollow" href="http://www.gnu.org/licenses/">http://www.gnu.org/licenses/</a>>.
+*/
+
+/* ACPI Filesystem header */
+
+#ifndef ACPIFS_H
+#define ACPIFS_H
+
+#include <hurd/netfs.h>
+#include <pthread.h>
+#include <maptime.h>
+
+#include <netfs_impl.h>
+#include <acpi.h>
+
+/* Size of a directory entry name */
+#ifndef NAME_SIZE
+#define NAME_SIZE 8
+#endif
+
+/* Node cache defaults size */
+#define NODE_CACHE_MAX 16
+
+/*
+ * User and group ids to grant permission to acpi
+ */
+struct acpifs_perm
+{
+  int32_t uid;
+  int32_t gid;
+};
+
+/*
+ * Directory entry.
+ *
+ * All directory entries are created on startup and used to generate the
+ * fs tree and create or retrieve libnetfs node objects.
+ *
+ * From libnetfs' point of view, these are the light nodes.
+ */
+struct acpifs_dirent
+{
+  char name[NAME_SIZE];
+  struct acpifs_dirent *parent;
+  io_statbuf_t stat;
+
+  /*
+   * We only need two kind of nodes: files and directories.
+   * When `dir' is null, this is a file; when not null, it's a directory.
+   */
+  struct acpifs_dir *dir;
+
+  /* Active node on this entry */
+  struct node *node;
+
+  /* ACPI table related to an entry */
+  struct acpi_table *acpitable;
+};
+
+/*
+ * A directory, it only contains a list of directory entries
+ */
+struct acpifs_dir
+{
+  /* Number of directory entries */
+  uint16_t num_entries;
+
+  /* Array of directory entries */
+  struct acpifs_dirent **entries;
+};
+
+/* A particular ACPI filesystem.  */
+struct acpifs
+{
+  /* Root of filesystem.  */
+  struct node *root;
+
+  /* A cache that holds a reference to recently used nodes.  */
+  struct node *node_cache_mru, *node_cache_lru;
+  size_t node_cache_len;       /* Number of entries in it.  */
+  size_t node_cache_max;
+  pthread_mutex_t node_cache_lock;
+
+  struct acpifs_perm perm;
+
+  struct acpifs_dirent *entries;
+  size_t num_entries;
+};
+
+/* Main FS pointer */
+struct acpifs *fs;
+
+/* Global mapped time */
+volatile struct mapped_time_value *acpifs_maptime;
+
+/* Update entry and node times */
+#define UPDATE_TIMES(e, what) (\
+  {\
+    fshelp_touch (&e->stat, what, acpifs_maptime);\
+    if(e->node)\
+      fshelp_touch (&e->node->nn_stat, what, acpifs_maptime);\
+  }\
+)
+
+/* Update entry and node owner */
+#define UPDATE_OWNER(e, uid) (\
+  {\
+    e->stat.st_uid = uid;\
+    if(e->node)\
+      e->node->nn_stat.st_uid = uid;\
+  }\
+)
+
+/* Update entry and node group */
+#define UPDATE_GROUP(e, gid) (\
+  {\
+    e->stat.st_gid = gid;\
+    if(e->node)\
+      e->node->nn_stat.st_gid = gid;\
+  }\
+)
+
+/* FS manipulation functions */
+error_t alloc_file_system (struct acpifs **fs);
+error_t init_file_system (file_t underlying_node, struct acpifs *fs);
+error_t create_fs_tree (struct acpifs *fs);
+error_t fs_set_permissions (struct acpifs *fs);
+error_t entry_check_perms (struct iouser *user, struct acpifs_dirent *e,
+                          int flags);
+
+#endif /* ACPIFS_H */