X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=lib%2Fringbuffer%2Fbackend.h;h=bbbc80d8eb03be444d4890d828d92f7f6eb118ab;hb=cf262f57baebeb3db47b4a44d0ab153b4d2abb2d;hp=826be933fe61bb45efbe96a7738823e3ae46af9e;hpb=7b8ea3a503536c9d00f8bb14958a150cbf7370c0;p=lttng-modules.git

diff --git a/lib/ringbuffer/backend.h b/lib/ringbuffer/backend.h
index 826be933..bbbc80d8 100644
--- a/lib/ringbuffer/backend.h
+++ b/lib/ringbuffer/backend.h
@@ -96,6 +96,8 @@ void lib_ring_buffer_write(const struct lib_ring_buffer_config *config,
 	struct lib_ring_buffer_backend_pages *rpages;
 	unsigned long sb_bindex, id;
 
+	if (unlikely(!len))
+		return;
 	offset &= chanb->buf_size - 1;
 	sbidx = offset >> chanb->subbuf_size_order;
 	index = (offset & (chanb->subbuf_size - 1)) >> PAGE_SHIFT;
@@ -142,6 +144,8 @@ void lib_ring_buffer_memset(const struct lib_ring_buffer_config *config,
 	struct lib_ring_buffer_backend_pages *rpages;
 	unsigned long sb_bindex, id;
 
+	if (unlikely(!len))
+		return;
 	offset &= chanb->buf_size - 1;
 	sbidx = offset >> chanb->subbuf_size_order;
 	index = (offset & (chanb->subbuf_size - 1)) >> PAGE_SHIFT;
@@ -189,6 +193,8 @@ void lib_ring_buffer_copy_from_user_inatomic(const struct lib_ring_buffer_config
 	unsigned long ret;
 	mm_segment_t old_fs = get_fs();
 
+	if (unlikely(!len))
+		return;
 	offset &= chanb->buf_size - 1;
 	sbidx = offset >> chanb->subbuf_size_order;
 	index = (offset & (chanb->subbuf_size - 1)) >> PAGE_SHIFT;
@@ -263,9 +269,4 @@ unsigned long lib_ring_buffer_get_records_unread(
 	return records_unread;
 }
 
-ssize_t lib_ring_buffer_file_splice_read(struct file *in, loff_t *ppos,
-					 struct pipe_inode_info *pipe,
-					 size_t len, unsigned int flags);
-loff_t lib_ring_buffer_no_llseek(struct file *file, loff_t offset, int origin);
-
 #endif /* _LIB_RING_BUFFER_BACKEND_H */