PCI Arbiter

1 files changed, 208 insertions, 0 deletions

diff --git a/pci-arbiter/pcifs.h b/pci-arbiter/pcifs.h
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+++ b/pci-arbiter/pcifs.h
@@ -0,0 +1,208 @@
+/*
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   Written by Miles Bader <miles@gnu.org>
+
+   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 <http://www.gnu.org/licenses/>.
+*/
+
+/* PCI Filesystem header */
+
+#ifndef PCIFS_H
+#define PCIFS_H
+
+#include <hurd/netfs.h>
+#include <pthread.h>
+#include <maptime.h>
+
+#include "pci_access.h"
+#include "netfs_impl.h"
+
+/* Size of a directory entry name */
+#ifndef NAME_SIZE
+#define NAME_SIZE 16
+#endif
+
+/* Node cache defaults size */
+#define NODE_CACHE_MAX 16
+
+/*
+ * Directory entry. Contains all per-node data our problem requires.
+ *
+ * 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 pcifs_dirent
+{
+  /*
+   * Complete bus identification, including domain, of the device.  On
+   * platforms that do not support PCI domains (e.g., 32-bit x86 hardware),
+   * the domain will always be zero.
+   *
+   * Negative value means no value.
+   */
+  int32_t domain;
+  int16_t bus;
+  int16_t dev;
+  int8_t func;
+
+  /*
+   * Device's class, subclass, and programming interface packed into a
+   * single 32-bit value.  The class is at bits [23:16], subclass is at
+   * bits [15:8], and programming interface is at [7:0].
+   *
+   * Negative value means no value.
+   */
+  int32_t device_class;
+
+  char name[NAME_SIZE];
+  struct pcifs_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 pcifs_dir *dir;
+
+  /* Active node on this entry */
+  struct node *node;
+
+  /*
+   * Underlying virtual device if any.
+   *
+   * Only for entries having a full B/D/F address.
+   */
+  struct pci_device *device;
+};
+
+/*
+ * A directory, it only contains a list of directory entries
+ */
+struct pcifs_dir
+{
+  /* Number of directory entries */
+  uint16_t num_entries;
+
+  /* Array of directory entries */
+  struct pcifs_dirent **entries;
+};
+
+/*
+ * Set of permissions.
+ *
+ * For each Class[,subclass] and/or Domain[,bus[,dev[,func]]], one UID and/or GID.
+ */
+struct pcifs_perm
+{
+  /*
+   * D/b/d/f scope of permissions.
+   *
+   * Negative value means no value.
+   */
+  int32_t domain;
+  int16_t bus;
+  int16_t dev;
+  int8_t func;
+
+  /*
+   * Class and subclass scope of permissions
+   *
+   * Negative value means no value.
+   */
+  int16_t d_class;
+  int16_t d_subclass;
+
+  /* User and group ids */
+  int32_t uid;
+  int32_t gid;
+};
+
+/* Various parameters that can be used to change the behavior of an ftpfs.  */
+struct pcifs_params
+{
+  /* The size of the node cache.  */
+  size_t node_cache_max;
+
+  /* FS permissions.  */
+  struct pcifs_perm *perms;
+  size_t num_perms;
+};
+
+/* A particular filesystem.  */
+struct pcifs
+{
+  /* Root of filesystem.  */
+  struct node *root;
+
+  /* FS configuration */
+  struct pcifs_params params;
+
+  /* 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.  */
+  pthread_mutex_t node_cache_lock;
+
+  /* Lock for pci_conf operations */
+  pthread_mutex_t pci_conf_lock;
+
+  struct pcifs_dirent *entries;
+  size_t num_entries;
+};
+
+/* Main FS pointer */
+struct pcifs *fs;
+
+/* Global mapped time */
+volatile struct mapped_time_value *pcifs_maptime;
+
+/* Update entry and node times */
+#define UPDATE_TIMES(e, what) (\
+  {\
+    fshelp_touch (&e->stat, what, pcifs_maptime);\
+    if(e->node)\
+      fshelp_touch (&e->node->nn_stat, what, pcifs_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 pcifs **fs);
+error_t init_file_system (file_t underlying_node, struct pcifs *fs);
+error_t create_fs_tree (struct pcifs *fs, struct pci_system *pci_sys);
+error_t fs_set_permissions (struct pcifs *fs);
+error_t entry_check_perms (struct iouser *user, struct pcifs_dirent *e,
+			   int flags);
+
+#endif /* PCIFS_H */