summaryrefslogtreecommitdiff
path: root/src/linux
diff options
context:
space:
mode:
authorLennart Poettering <lennart@poettering.net>2010-09-23 15:01:41 +0200
committerLennart Poettering <lennart@poettering.net>2010-09-23 15:02:13 +0200
commit22be093ffb403a1c474037939ca9b88b1ee39f77 (patch)
tree99b06c7fa271316661a2c3e2ea9bd69ff370a53f /src/linux
parent647703fecb8c9928d0f13fd95d17fd5f2280c7e1 (diff)
readahead: implement minimal readahead logic based on fanotify(), mincore() and readahead()
Diffstat (limited to 'src/linux')
-rw-r--r--src/linux/fanotify.h98
1 files changed, 98 insertions, 0 deletions
diff --git a/src/linux/fanotify.h b/src/linux/fanotify.h
new file mode 100644
index 0000000000..63531a6b4d
--- /dev/null
+++ b/src/linux/fanotify.h
@@ -0,0 +1,98 @@
+#ifndef _LINUX_FANOTIFY_H
+#define _LINUX_FANOTIFY_H
+
+#include <linux/types.h>
+
+/* the following events that user-space can register for */
+#define FAN_ACCESS 0x00000001 /* File was accessed */
+#define FAN_MODIFY 0x00000002 /* File was modified */
+#define FAN_CLOSE_WRITE 0x00000008 /* Unwrittable file closed */
+#define FAN_CLOSE_NOWRITE 0x00000010 /* Writtable file closed */
+#define FAN_OPEN 0x00000020 /* File was opened */
+
+#define FAN_EVENT_ON_CHILD 0x08000000 /* interested in child events */
+
+/* FIXME currently Q's have no limit.... */
+#define FAN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */
+
+#define FAN_OPEN_PERM 0x00010000 /* File open in perm check */
+#define FAN_ACCESS_PERM 0x00020000 /* File accessed in perm check */
+
+/* helper events */
+#define FAN_CLOSE (FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
+
+/* flags used for fanotify_init() */
+#define FAN_CLOEXEC 0x00000001
+#define FAN_NONBLOCK 0x00000002
+
+#define FAN_ALL_INIT_FLAGS (FAN_CLOEXEC | FAN_NONBLOCK)
+
+/* flags used for fanotify_modify_mark() */
+#define FAN_MARK_ADD 0x00000001
+#define FAN_MARK_REMOVE 0x00000002
+#define FAN_MARK_DONT_FOLLOW 0x00000004
+#define FAN_MARK_ONLYDIR 0x00000008
+#define FAN_MARK_MOUNT 0x00000010
+#define FAN_MARK_IGNORED_MASK 0x00000020
+#define FAN_MARK_IGNORED_SURV_MODIFY 0x00000040
+#define FAN_MARK_FLUSH 0x00000080
+
+#define FAN_ALL_MARK_FLAGS (FAN_MARK_ADD |\
+ FAN_MARK_REMOVE |\
+ FAN_MARK_DONT_FOLLOW |\
+ FAN_MARK_ONLYDIR |\
+ FAN_MARK_MOUNT |\
+ FAN_MARK_IGNORED_MASK |\
+ FAN_MARK_IGNORED_SURV_MODIFY)
+
+/*
+ * All of the events - we build the list by hand so that we can add flags in
+ * the future and not break backward compatibility. Apps will get only the
+ * events that they originally wanted. Be sure to add new events here!
+ */
+#define FAN_ALL_EVENTS (FAN_ACCESS |\
+ FAN_MODIFY |\
+ FAN_CLOSE |\
+ FAN_OPEN)
+
+/*
+ * All events which require a permission response from userspace
+ */
+#define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
+ FAN_ACCESS_PERM)
+
+#define FAN_ALL_OUTGOING_EVENTS (FAN_ALL_EVENTS |\
+ FAN_ALL_PERM_EVENTS |\
+ FAN_Q_OVERFLOW)
+
+#define FANOTIFY_METADATA_VERSION 2
+
+struct fanotify_event_metadata {
+ __u32 event_len;
+ __u32 vers;
+ __u64 mask;
+ __s32 fd;
+ __s32 pid;
+} __attribute__ ((packed));
+
+struct fanotify_response {
+ __s32 fd;
+ __u32 response;
+} __attribute__ ((packed));
+
+/* Legit userspace responses to a _PERM event */
+#define FAN_ALLOW 0x01
+#define FAN_DENY 0x02
+
+/* Helper functions to deal with fanotify_event_metadata buffers */
+#define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
+
+#define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
+ (struct fanotify_event_metadata*)(((char *)(meta)) + \
+ (meta)->event_len))
+
+#define FAN_EVENT_OK(meta, len) ((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
+ (long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
+ (long)(meta)->event_len <= (long)(len))
+
+#endif /* _LINUX_FANOTIFY_H */