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-rw-r--r--fs/relayfs/buffers.c2
-rw-r--r--fs/relayfs/relay.c30
-rw-r--r--include/linux/relayfs_fs.h34
3 files changed, 63 insertions, 3 deletions
diff --git a/fs/relayfs/buffers.c b/fs/relayfs/buffers.c
index 667b529944c5..10187812771e 100644
--- a/fs/relayfs/buffers.c
+++ b/fs/relayfs/buffers.c
@@ -185,6 +185,6 @@ void relay_destroy_buf(struct rchan_buf *buf)
void relay_remove_buf(struct kref *kref)
{
struct rchan_buf *buf = container_of(kref, struct rchan_buf, kref);
- relayfs_remove(buf->dentry);
+ buf->chan->cb->remove_buf_file(buf->dentry);
relay_destroy_buf(buf);
}
diff --git a/fs/relayfs/relay.c b/fs/relayfs/relay.c
index a9cd5585c45c..b9bb56903272 100644
--- a/fs/relayfs/relay.c
+++ b/fs/relayfs/relay.c
@@ -80,11 +80,33 @@ static void buf_unmapped_default_callback(struct rchan_buf *buf,
{
}
+/*
+ * create_buf_file_create() default callback. Creates file to represent buf.
+ */
+static struct dentry *create_buf_file_default_callback(const char *filename,
+ struct dentry *parent,
+ int mode,
+ struct rchan_buf *buf)
+{
+ return relayfs_create_file(filename, parent, mode,
+ &relayfs_file_operations, buf);
+}
+
+/*
+ * remove_buf_file() default callback. Removes file representing relay buffer.
+ */
+static int remove_buf_file_default_callback(struct dentry *dentry)
+{
+ return relayfs_remove(dentry);
+}
+
/* relay channel default callbacks */
static struct rchan_callbacks default_channel_callbacks = {
.subbuf_start = subbuf_start_default_callback,
.buf_mapped = buf_mapped_default_callback,
.buf_unmapped = buf_unmapped_default_callback,
+ .create_buf_file = create_buf_file_default_callback,
+ .remove_buf_file = remove_buf_file_default_callback,
};
/**
@@ -176,8 +198,8 @@ static struct rchan_buf *relay_open_buf(struct rchan *chan,
return NULL;
/* Create file in fs */
- dentry = relayfs_create_file(filename, parent, S_IRUSR,
- &relayfs_file_operations, buf);
+ dentry = chan->cb->create_buf_file(filename, parent, S_IRUSR,
+ buf);
if (!dentry) {
relay_destroy_buf(buf);
return NULL;
@@ -220,6 +242,10 @@ static inline void setup_callbacks(struct rchan *chan,
cb->buf_mapped = buf_mapped_default_callback;
if (!cb->buf_unmapped)
cb->buf_unmapped = buf_unmapped_default_callback;
+ if (!cb->create_buf_file)
+ cb->create_buf_file = create_buf_file_default_callback;
+ if (!cb->remove_buf_file)
+ cb->remove_buf_file = remove_buf_file_default_callback;
chan->cb = cb;
}
diff --git a/include/linux/relayfs_fs.h b/include/linux/relayfs_fs.h
index 8200ecbe6e0f..8c2177105857 100644
--- a/include/linux/relayfs_fs.h
+++ b/include/linux/relayfs_fs.h
@@ -110,6 +110,40 @@ struct rchan_callbacks
*/
void (*buf_unmapped)(struct rchan_buf *buf,
struct file *filp);
+ /*
+ * create_buf_file - create file to represent a relayfs channel buffer
+ * @filename: the name of the file to create
+ * @parent: the parent of the file to create
+ * @mode: the mode of the file to create
+ * @buf: the channel buffer
+ *
+ * Called during relay_open(), once for each per-cpu buffer,
+ * to allow the client to create a file to be used to
+ * represent the corresponding channel buffer. If the file is
+ * created outside of relayfs, the parent must also exist in
+ * that filesystem.
+ *
+ * The callback should return the dentry of the file created
+ * to represent the relay buffer.
+ *
+ * See Documentation/filesystems/relayfs.txt for more info.
+ */
+ struct dentry *(*create_buf_file)(const char *filename,
+ struct dentry *parent,
+ int mode,
+ struct rchan_buf *buf);
+
+ /*
+ * remove_buf_file - remove file representing a relayfs channel buffer
+ * @dentry: the dentry of the file to remove
+ *
+ * Called during relay_close(), once for each per-cpu buffer,
+ * to allow the client to remove a file used to represent a
+ * channel buffer.
+ *
+ * The callback should return 0 if successful, negative if not.
+ */
+ int (*remove_buf_file)(struct dentry *dentry);
};
/*
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