Orangefs: kernel client part 1

OrangeFS (formerly PVFS) is an lgpl licensed userspace networked parallel
file system. OrangeFS can be accessed through included system utilities,
user integration libraries, MPI-IO and can be used by the Hadoop
ecosystem as an alternative to the HDFS filesystem. OrangeFS is used
widely for parallel science, data analytics and engineering applications.

While applications often don't require Orangefs to be mounted into
the VFS, users do like to be able to access their files in the normal way.
The Orangefs kernel client allows Orangefs filesystems to be mounted as
a VFS. The kernel client communicates with a userspace daemon which in
turn communicates with the Orangefs server daemons that implement the
filesystem. The server daemons (there's almost always more than one)
need not be running on the same host as the kernel client.

Orangefs filesystems can also be mounted with FUSE, and we
ship code and instructions to facilitate that, but most of our users
report preferring to use our kernel module instead. Further, as an example
of a problem we can't solve with fuse, we have in the works a
not-yet-ready-for-prime-time version of a file_operations lock function
that accounts for the server daemons being distributed across more
than one running kernel.

Many people and organizations, including Clemson University,
Argonne National Laboratories and Acxiom Corporation have
helped to create what has become Orangefs over more than twenty
years. Some of the more recent contributors to the kernel client
include:

  Mike Marshall
  Christoph Hellwig
  Randy Martin
  Becky Ligon
  Walt Ligon
  Michael Moore
  Rob Ross
  Phil Carnes

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

1 files changed, 138 insertions, 0 deletions

diff --git a/fs/orangefs/downcall.h b/fs/orangefs/downcall.h
new file mode 100644
index 000000000000..a79129f875f3
--- /dev/null
+++ b/fs/orangefs/downcall.h
@@ -0,0 +1,138 @@
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Definitions of downcalls used in Linux kernel module.
+ */
+
+#ifndef __DOWNCALL_H
+#define __DOWNCALL_H
+
+/*
+ * Sanitized the device-client core interaction
+ * for clean 32-64 bit usage
+ */
+struct pvfs2_io_response {
+	__s64 amt_complete;
+};
+
+struct pvfs2_iox_response {
+	__s64 amt_complete;
+};
+
+struct pvfs2_lookup_response {
+	struct pvfs2_object_kref refn;
+};
+
+struct pvfs2_create_response {
+	struct pvfs2_object_kref refn;
+};
+
+struct pvfs2_symlink_response {
+	struct pvfs2_object_kref refn;
+};
+
+struct pvfs2_getattr_response {
+	struct PVFS_sys_attr_s attributes;
+	char link_target[PVFS2_NAME_LEN];
+};
+
+struct pvfs2_mkdir_response {
+	struct pvfs2_object_kref refn;
+};
+
+/*
+ * duplication of some system interface structures so that I don't have
+ * to allocate extra memory
+ */
+struct pvfs2_dirent {
+	char *d_name;
+	int d_length;
+	struct pvfs2_khandle khandle;
+};
+
+struct pvfs2_statfs_response {
+	__s64 block_size;
+	__s64 blocks_total;
+	__s64 blocks_avail;
+	__s64 files_total;
+	__s64 files_avail;
+};
+
+struct pvfs2_fs_mount_response {
+	__s32 fs_id;
+	__s32 id;
+	struct pvfs2_khandle root_khandle;
+};
+
+/* the getxattr response is the attribute value */
+struct pvfs2_getxattr_response {
+	__s32 val_sz;
+	__s32 __pad1;
+	char val[PVFS_MAX_XATTR_VALUELEN];
+};
+
+/* the listxattr response is an array of attribute names */
+struct pvfs2_listxattr_response {
+	__s32 returned_count;
+	__s32 __pad1;
+	__u64 token;
+	char key[PVFS_MAX_XATTR_LISTLEN * PVFS_MAX_XATTR_NAMELEN];
+	__s32 keylen;
+	__s32 __pad2;
+	__s32 lengths[PVFS_MAX_XATTR_LISTLEN];
+};
+
+struct pvfs2_param_response {
+	__s64 value;
+};
+
+#define PERF_COUNT_BUF_SIZE 4096
+struct pvfs2_perf_count_response {
+	char buffer[PERF_COUNT_BUF_SIZE];
+};
+
+#define FS_KEY_BUF_SIZE 4096
+struct pvfs2_fs_key_response {
+	__s32 fs_keylen;
+	__s32 __pad1;
+	char fs_key[FS_KEY_BUF_SIZE];
+};
+
+struct pvfs2_downcall_s {
+	__s32 type;
+	__s32 status;
+	/* currently trailer is used only by readdir */
+	__s64 trailer_size;
+	char * trailer_buf;
+
+	union {
+		struct pvfs2_io_response io;
+		struct pvfs2_iox_response iox;
+		struct pvfs2_lookup_response lookup;
+		struct pvfs2_create_response create;
+		struct pvfs2_symlink_response sym;
+		struct pvfs2_getattr_response getattr;
+		struct pvfs2_mkdir_response mkdir;
+		struct pvfs2_statfs_response statfs;
+		struct pvfs2_fs_mount_response fs_mount;
+		struct pvfs2_getxattr_response getxattr;
+		struct pvfs2_listxattr_response listxattr;
+		struct pvfs2_param_response param;
+		struct pvfs2_perf_count_response perf_count;
+		struct pvfs2_fs_key_response fs_key;
+	} resp;
+};
+
+struct pvfs2_readdir_response_s {
+	__u64 token;
+	__u64 directory_version;
+	__u32 __pad2;
+	__u32 pvfs_dirent_outcount;
+	struct pvfs2_dirent *dirent_array;
+};
+
+#endif /* __DOWNCALL_H */