At least since nodemgr got rid of coarse global locking, accesses to
struct csr1212_keyval's reference counter should be atomic and coupled
with proper barriers. Also, calls to csr1212_keep_keyval(kv) should
occur before kv is being used.
(We probably should convert refcnt to struct kref, but how to keep
csr1212_destroy_keyval's implementation non-recursively then?)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The biggest chunk ever allocated by CSR1212_MALLOC is 1024 Bytes +
sizeof(struct csr1212_csr_rom_cache) big. Most of the time much
smaller data structures are allocated. Therefore vmalloc is a waste.
The one exception is csr1212_append_new_cache() which is called to
append a chunk of CSR1212_EXTENDED_ROM_SIZE + sizeof(struct
csr1212_csr_rom_cache) if the currently allocated ROM cache is too
small. CSR1212_EXTENDED_ROM_SIZE is generously defined as 256 kBytes.
In SVN commit 1220, Steve Kinneberg lowered this to 2 kBytes in the
config_rom_2.4 branch. This same commit also switched CSR1212_MALLOC
from kmalloc to vmalloc in the SVN trunk branch:
> r1220 | kberg | 2004-05-31 01:51:44 +0200 (Mon, 31 May 2004) | 13 lines
>
> CSR1212 Extended ROM bug fixes:
> trunk line changes:
> - Use vmalloc instead of kmalloc
> - Change delayed_reset_bus() to operate in a work_queue instead of a
> timer interrupt.
> - Fix hpsb_allocate_and_register_addrspace() to not allocate space
> on top of already allocated space.
> - Fix problems in csr1212.c filling ConfigROM images when extend
> ROMs are present.
> config-rom-2.4 changes:
> - Changed extended rom allocation from 256K to 8K.
(It was actually 2 kB, not 8 kB.)
> - Fix hpsb_allocate_and_register_addrspace() to not allocate space
> on top of already allocated space.
> - Fix problems in csr1212.c filling ConfigROM images when extend
> ROMs are present.
I am now setting CSR1212_EXTENDED_ROM_SIZE to 2 kB minus the overhead of
struct csr1212_csr_rom_cache. Note, this code path is not used by the
in-kernel drivers though. raw1394 could trigger it, but the respective
libraw1394 functions don't exist yet.
Furthermore, userspace programs can replace the entire local ROM via
raw1394. If kmalloc does not fulfill their needs --- well, tough luck.
I decree that nobody needs such huge extended ROMs. (Extended ROMs are
defined by IEEE 1212 clause 7.7.18. The spec does not impose
practically relevant restrictions on the size of extended ROM chunks.)
Another potentially demanding use of CSR1212_MALLOC is if external
FireWire devices come with Extended ROM entries. If they are too big
for kmalloc (or have been too big for vmalloc) we just fail to read
their ROM. This is quite unlikely though, to my knowledge.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This small reorganization of public csr1212 functions saves one
exported symbol and a few bytes in the driver modules.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
csr1212 was written to be compiled either as part of the ieee1394 kernel
driver or of an anticipated IEEE 1212 userspace library. We now drop
support for the latter. The costs in terms of code footprint and depth
of abstraction are not countered by any actual benefit.
Also remove some obsolete #includes.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Delete unused code.
Make some extern functions static.
Remove superfluous inline keywords.
Move private definitions from csr1212.h to csr1212.c.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Replace occurrences of the magic value ~(u64)0 for invalid
CSR address spaces by a named constant for better readability.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Ben Collins <bcollins@ubuntu.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Stefan Richter
Ben Collins
Jody McIntyre
Linus Torvalds