path: root/arch/s390/hypfs/hypfs.h
diff options
authorMichael Holzheu <holzheu@de.ibm.com>2006-06-23 02:05:06 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-06-23 07:43:02 -0700
commit24bbb1faf3f0420eb252dd0fdc1e477b1d4d73bd (patch)
treece7f9358fdeaa4f299cb996e8a1d4224d51ee4c4 /arch/s390/hypfs/hypfs.h
parent[PATCH] xtensa: remove verify_area macros (diff)
[PATCH] s390_hypfs filesystem
On zSeries machines there exists an interface which allows the operating system to retrieve LPAR hypervisor accounting data. For example, it is possible to get usage data for physical and virtual cpus. In order to provide this information to user space programs, I implemented a new virtual Linux file system named 's390_hypfs' using the Linux 2.6 libfs framework. The name 's390_hypfs' stands for 'S390 Hypervisor Filesystem'. All the accounting information is put into different virtual files which can be accessed from user space. All data is represented as ASCII strings. When the file system is mounted the accounting information is retrieved and a file system tree is created with the attribute files containing the cpu information. The content of the files remains unchanged until a new update is made. An update can be triggered from user space through writing 'something' into a special purpose update file. We create the following directory structure: <mount-point>/ update cpus/ <cpu-id> type mgmtime <cpu-id> ... hyp/ type systems/ <lpar-name> cpus/ <cpu-id> type mgmtime cputime onlinetime <cpu-id> ... <lpar-name> cpus/ ... - update: File to trigger update - cpus/: Directory for all physical cpus - cpus/<cpu-id>/: Directory for one physical cpu. - cpus/<cpu-id>/type: Type name of physical zSeries cpu. - cpus/<cpu-id>/mgmtime: Physical-LPAR-management time in microseconds. - hyp/: Directory for hypervisor information - hyp/type: Typ of hypervisor (currently only 'LPAR Hypervisor') - systems/: Directory for all LPARs - systems/<lpar-name>/: Directory for one LPAR. - systems/<lpar-name>/cpus/<cpu-id>/: Directory for the virtual cpus - systems/<lpar-name>/cpus/<cpu-id>/type: Typ of cpu. - systems/<lpar-name>/cpus/<cpu-id>/mgmtime: Accumulated number of microseconds during which a physical CPU was assigned to the logical cpu and the cpu time was consumed by the hypervisor and was not provided to the LPAR (LPAR overhead). - systems/<lpar-name>/cpus/<cpu-id>/cputime: Accumulated number of microseconds during which a physical CPU was assigned to the logical cpu and the cpu time was consumed by the LPAR. - systems/<lpar-name>/cpus/<cpu-id>/onlinetime: Accumulated number of microseconds during which the logical CPU has been online. As mount point for the filesystem /sys/hypervisor/s390 is created. The update process is triggered when writing 'something' into the 'update' file at the top level hypfs directory. You can do this e.g. with 'echo 1 > update'. During the update the whole directory structure is deleted and built up again. Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Ingo Oeser <ioe-lkml@rameria.de> Cc: Joern Engel <joern@wohnheim.fh-wedel.de> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to '')
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/s390/hypfs/hypfs.h b/arch/s390/hypfs/hypfs.h
new file mode 100644
index 000000000000..ea5567be00fc
--- /dev/null
+++ b/arch/s390/hypfs/hypfs.h
@@ -0,0 +1,30 @@
+ * fs/hypfs/hypfs.h
+ * Hypervisor filesystem for Linux on s390.
+ *
+ * Copyright (C) IBM Corp. 2006
+ * Author(s): Michael Holzheu <holzheu@de.ibm.com>
+ */
+#ifndef _HYPFS_H_
+#define _HYPFS_H_
+#include <linux/fs.h>
+#include <linux/types.h>
+#define REG_FILE_MODE 0440
+#define UPDATE_FILE_MODE 0220
+#define DIR_MODE 0550
+extern struct dentry *hypfs_mkdir(struct super_block *sb, struct dentry *parent,
+ const char *name);
+extern struct dentry *hypfs_create_u64(struct super_block *sb,
+ struct dentry *dir, const char *name,
+ __u64 value);
+extern struct dentry *hypfs_create_str(struct super_block *sb,
+ struct dentry *dir, const char *name,
+ char *string);
+#endif /* _HYPFS_H_ */