1. 20 Feb, 2012 27 commits
  2. 19 Feb, 2012 3 commits
    • David Howells's avatar
      Delete the __FD_*() funcs for operating on fd_set from linux/time.h · cf420048
      David Howells authored
      
      
      Delete the __FD_*() functions for operating on fd_set structs from
      linux/time.h as they're no longer used within the kernel with the preceding
      patch and are not exported to userspace.
      
      Whilst linux/time.h *does* export the FD_*() equivalents as wrappers around
      __FD_*(), userspace provides its own definition of __FD_*().
      
      Note that the definition of FD_ZERO() in linux/time.h may not be used with the
      fd_sets associated with struct fdtable as the fd_set may have been allocated in
      a truncated fashion.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Link: http://lkml.kernel.org/r/20120216175006.23314.18984.stgit@warthog.procyon.org.uk
      
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      cf420048
    • David Howells's avatar
      Replace the fd_sets in struct fdtable with an array of unsigned longs · 1fd36adc
      David Howells authored
      
      
      Replace the fd_sets in struct fdtable with an array of unsigned longs and then
      use the standard non-atomic bit operations rather than the FD_* macros.
      
      This:
      
       (1) Removes the abuses of struct fd_set:
      
           (a) Since we don't want to allocate a full fd_set the vast majority of the
           	 time, we actually, in effect, just allocate a just-big-enough array of
           	 unsigned longs and cast it to an fd_set type - so why bother with the
           	 fd_set at all?
      
           (b) Some places outside of the core fdtable handling code (such as
           	 SELinux) want to look inside the array of unsigned longs hidden inside
           	 the fd_set struct for more efficient iteration over the entire set.
      
       (2) Eliminates the use of FD_*() macros in the kernel completely.
      
       (3) Permits the __FD_*() macros to be deleted entirely where not exposed to
           userspace.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Link: http://lkml.kernel.org/r/20120216174954.23314.48147.stgit@warthog.procyon.org.uk
      
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      1fd36adc
    • David Howells's avatar
      Wrap accesses to the fd_sets in struct fdtable · 1dce27c5
      David Howells authored
      
      
      Wrap accesses to the fd_sets in struct fdtable (for recording open files and
      close-on-exec flags) so that we can move away from using fd_sets since we
      abuse the fd_set structs by not allocating the full-sized structure under
      normal circumstances and by non-core code looking at the internals of the
      fd_sets.
      
      The first abuse means that use of FD_ZERO() on these fd_sets is not permitted,
      since that cannot be told about their abnormal lengths.
      
      This introduces six wrapper functions for setting, clearing and testing
      close-on-exec flags and fd-is-open flags:
      
      	void __set_close_on_exec(int fd, struct fdtable *fdt);
      	void __clear_close_on_exec(int fd, struct fdtable *fdt);
      	bool close_on_exec(int fd, const struct fdtable *fdt);
      	void __set_open_fd(int fd, struct fdtable *fdt);
      	void __clear_open_fd(int fd, struct fdtable *fdt);
      	bool fd_is_open(int fd, const struct fdtable *fdt);
      
      Note that I've prepended '__' to the names of the set/clear functions because
      they require the caller to hold a lock to use them.
      
      Note also that I haven't added wrappers for looking behind the scenes at the
      the array.  Possibly that should exist too.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Link: http://lkml.kernel.org/r/20120216174942.23314.1364.stgit@warthog.procyon.org.uk
      
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      1dce27c5
  3. 14 Feb, 2012 10 commits