Commit Graph

10 Commits

Author SHA1 Message Date
Andriy Gapon
e76f11f441 strict kobj signatures: linker_if fixes
in symtab_get method symtab parameter is made constant as this reflects
actual intention and usage of the method

Reviewed by:	imp, current@
Approved by:	jhb (mentor)
2009-06-11 17:05:45 +00:00
Stacey Son
00a5db46de Add the ksyms(4) pseudo driver. The ksyms driver allows a process to
get a quick snapshot of the kernel's symbol table including the symbols
from any loaded modules (the symbols are all merged into one symbol
table).  Unlike like other implementations, this ksyms driver maps
memory in the process memory space to store the snapshot at the time
/dev/ksyms is opened.  It also checks to see if the process has already
a snapshot open and won't allow it to open /dev/ksyms it again until it
closes first.  This prevents kernel and process memory from being
exhausted.  Note that /dev/ksyms is used by the lockstat(1) command.

Reviewed by:	gallatin kib (freebsd-arch)
Approved by:	gnn (mentor)
2009-05-26 21:39:09 +00:00
John Birrell
82c4945b5b Add the ctf_get method. 2008-05-23 04:06:49 +00:00
John Birrell
f6c1530162 Add a function to list symbols in a file and their values at the
same time rather than having to list the symbols and then go back
and look each one up by name.
2007-11-18 00:23:31 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
Doug Rabson
ab7a2646e0 The method link_preload_finish is not static. 2003-09-20 17:39:32 +00:00
Brian Feldman
bb9fe9dd9e Add the sysctl "kern.function_list", which currently exports all
function symbols in the kernel in a list of C strings, with an extra
nul-termination at the end.

This sysctl requires addition of a new linker operation.  Now,
linker_file_t's need to respond to "each_function_name" to export
their function symbols.

Note that the sysctl doesn't currently allow distinguishing multiple
symbols with the same name from different modules, but could quite
easily without a change to the linker operation.  This will be a nicety
to have when it can be used.

Obtained from:	NAI Labs CBOSS project
Funded by:	DARPA
2001-10-30 15:21:45 +00:00
Peter Wemm
f41325db5f With this commit, I hereby pronounce gensetdefs past its use-by date.
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible.  <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.

The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).

The macros declare a strongly typed set.  They return elements with the
type that you declare the set with, rather than a generic void *.

For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>).  Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.

For a.out, we use the old linker_set struct.

NOTE: the item lists are no longer null terminated.  This is why
the code impact is high in certain areas.

The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.

linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.

Reviewed by:	eivind
2001-06-13 10:58:39 +00:00
Peter Wemm
54823af256 First round implementation of a fine grain enhanced module to module
version dependency system.  This isn't quite finished, but it is at a
useful stage to do a functional checkpoint.

Highlights:
- version and dependency metadata is gathered via linker sets, so things
are handled the same for static kernels and code built to live in a kld.
- The dependencies are at module level (versus at file level).
- Dependencies determine kld symbol search order - this means that you
cannot link against symbols in another file unless you depend on it. This
is so that you cannot accidently unload the target out from underneath
the ones referencing it.
- It is flexible enough that we can put tags in #include files and macros
so that we can get decent hooks for enforcing recompiles on incompatable
ABI changes.  eg: if we change struct proc, we could force a recompile
for all kld's that reference the proc struct.
- Tangled dependency references at boot time are sorted.  Files are
relocated once all their dependencies are already relocated.

Caveats:
- Loader support is incomplete, but has been worked on seperately.
- Actual enforcement of the version number tags is not active yet - just
the module dependencies are live.  The actual structure of versioning
hasn't been agreed on yet. (eg: major.minor, or whatever)
- There is some backwards compatability for old modules without metadata
but I'm not sure how good it is.

This is based on work originally done by Boris Popov (bp@freebsd.org),
but I'm not sure he'd recognize much of it now. Don't blame him. :-)
Also, ideas have been borrowed from Mike Smith.
2000-04-29 13:19:31 +00:00
Doug Rabson
326e27d81f * Rewrite to use kobj(9) instead of hard-coded function tables.
* Report link errors to stdout with uprintf() so that the user can see
  what went wrong (PR kern/9214).
* Add support code to allow module symbols to be loaded into GDB using
  the debugger's "sharedlibrary" command.
2000-04-24 17:08:04 +00:00