summaryrefslogtreecommitdiff
path: root/include/linux/relay.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/relay.h')
-rw-r--r--include/linux/relay.h29
1 files changed, 8 insertions, 21 deletions
diff --git a/include/linux/relay.h b/include/linux/relay.h
index e13a333e7c37..72b876dd5cb8 100644
--- a/include/linux/relay.h
+++ b/include/linux/relay.h
@@ -62,7 +62,7 @@ struct rchan
size_t subbuf_size; /* sub-buffer size */
size_t n_subbufs; /* number of sub-buffers per buffer */
size_t alloc_size; /* total buffer size allocated */
- struct rchan_callbacks *cb; /* client callbacks */
+ const struct rchan_callbacks *cb; /* client callbacks */
struct kref kref; /* channel refcount */
void *private_data; /* for user-defined data */
size_t last_toobig; /* tried to log event > subbuf size */
@@ -89,6 +89,8 @@ struct rchan_callbacks
* The client should return 1 to continue logging, 0 to stop
* logging.
*
+ * This callback is optional.
+ *
* NOTE: subbuf_start will also be invoked when the buffer is
* created, so that the first sub-buffer can be initialized
* if necessary. In this case, prev_subbuf will be NULL.
@@ -102,25 +104,6 @@ struct rchan_callbacks
size_t prev_padding);
/*
- * buf_mapped - relay buffer mmap notification
- * @buf: the channel buffer
- * @filp: relay file pointer
- *
- * Called when a relay file is successfully mmapped
- */
- void (*buf_mapped)(struct rchan_buf *buf,
- struct file *filp);
-
- /*
- * buf_unmapped - relay buffer unmap notification
- * @buf: the channel buffer
- * @filp: relay file pointer
- *
- * Called when a relay file is successfully unmapped
- */
- void (*buf_unmapped)(struct rchan_buf *buf,
- struct file *filp);
- /*
* create_buf_file - create file to represent a relay channel buffer
* @filename: the name of the file to create
* @parent: the parent of the file to create
@@ -141,6 +124,8 @@ struct rchan_callbacks
* cause relay_open() to create a single global buffer rather
* than the default set of per-cpu buffers.
*
+ * This callback is mandatory.
+ *
* See Documentation/filesystems/relay.rst for more info.
*/
struct dentry *(*create_buf_file)(const char *filename,
@@ -158,6 +143,8 @@ struct rchan_callbacks
* channel buffer.
*
* The callback should return 0 if successful, negative if not.
+ *
+ * This callback is mandatory.
*/
int (*remove_buf_file)(struct dentry *dentry);
};
@@ -170,7 +157,7 @@ struct rchan *relay_open(const char *base_filename,
struct dentry *parent,
size_t subbuf_size,
size_t n_subbufs,
- struct rchan_callbacks *cb,
+ const struct rchan_callbacks *cb,
void *private_data);
extern int relay_late_setup_files(struct rchan *chan,
const char *base_filename,