wrapper/splice.h

   1 #ifndef _LTT_WRAPPER_SPLICE_H
   2 #define _LTT_WRAPPER_SPLICE_H
   3
   4 /*
   5  * Copyright (C) 2011 Mathieu Desnoyers (mathieu.desnoyers@efficios.com)
   6  *
   7  * wrapper around vmalloc_sync_all. Using KALLSYMS to get its address when
   8  * available, else we need to have a kernel that exports this function to GPL
   9  * modules.
  10  *
  11  * Dual LGPL v2.1/GPL v2 license.
  12  */
  13
  14 #ifdef CONFIG_KALLSYMS
  15
  16 #include <linux/kallsyms.h>
  17 #include <linux/splice.h>
  18
  19 static inline
  20 ssize_t wrapper_splice_to_pipe(struct pipe_inode_info *pipe,
  21                                struct splice_pipe_desc *spd)
  22 {
  23         ssize_t (*splice_to_pipe_sym)(struct pipe_inode_info *pipe,
  24                                       struct splice_pipe_desc *spd);
  25
  26         splice_to_pipe_sym = (void *) kallsyms_lookup_name("splice_to_pipe");
  27         if (splice_to_pipe_sym) {
  28                 return splice_to_pipe_sym(pipe, spd);
  29         } else {
  30                 printk(KERN_WARNING "LTTng: splice_to_pipe symbol lookup failed.\n");
  31                 return -ENOSYS;
  32         }
  33 }
  34 #else
  35
  36 #include <linux/splice.h>
  37
  38 static inline
  39 ssize_t wrapper_splice_to_pipe(struct pipe_inode_info *pipe,
  40                                struct splice_pipe_desc *spd)
  41 {
  42         return splice_to_pipe(pipe, spd);
  43 }
  44 #endif
  45
  46 #endif /* _LTT_WRAPPER_SPLICE_H */