This changes the interfaces in <asm/word-at-a-time.h> to be a bit more
complicated, but a lot more generic.
In particular, it allows us to really do the operations efficiently on
both little-endian and big-endian machines, pretty much regardless of
machine details. For example, if you can rely on a fast population
count instruction on your architecture, this will allow you to make your
optimized <asm/word-at-a-time.h> file with that.
NOTE! The "generic" version in include/asm-generic/word-at-a-time.h is
not truly generic, it actually only works on big-endian. Why? Because
on little-endian the generic algorithms are wasteful, since you can
inevitably do better. The x86 implementation is an example of that.
(The only truly non-generic part of the asm-generic implementation is
the "find_zero()" function, and you could make a little-endian version
of it. And if the Kbuild infrastructure allowed us to pick a particular
header file, that would be lovely)
The <asm/word-at-a-time.h> functions are as follows:
- WORD_AT_A_TIME_CONSTANTS: specific constants that the algorithm
uses.
- has_zero(): take a word, and determine if it has a zero byte in it.
It gets the word, the pointer to the constant pool, and a pointer to
an intermediate "data" field it can set.
This is the "quick-and-dirty" zero tester: it's what is run inside
the hot loops.
- "prep_zero_mask()": take the word, the data that has_zero() produced,
and the constant pool, and generate an *exact* mask of which byte had
the first zero. This is run directly *outside* the loop, and allows
the "has_zero()" function to answer the "is there a zero byte"
question without necessarily getting exactly *which* byte is the
first one to contain a zero.
If you do multiple byte lookups concurrently (eg "hash_name()", which
looks for both NUL and '/' bytes), after you've done the prep_zero_mask()
phase, the result of those can be or'ed together to get the "either
or" case.
- The result from "prep_zero_mask()" can then be fed into "find_zero()"
(to find the byte offset of the first byte that was zero) or into
"zero_bytemask()" (to find the bytemask of the bytes preceding the
zero byte).
The existence of zero_bytemask() is optional, and is not necessary
for the normal string routines. But dentry name hashing needs it, so
if you enable DENTRY_WORD_AT_A_TIME you need to expose it.
This changes the generic strncpy_from_user() function and the dentry
hashing functions to use these modified word-at-a-time interfaces. This
gets us back to the optimized state of the x86 strncpy that we lost in
the previous commit when moving over to the generic version.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's unknown why openprom.h was being exported; there doesn't seem to be any
reason for it currently, and it creates headaches with userspace being able
to potentially use the structures in there. So, don't export it anymore.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Add swab.h to kbuild.asm and remove the individual entries from
each arch, mark as unifdef as some arches have some kernel-only
bits inside.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ony difference is the size of the mode.
sparc has extra padding to compensate for this.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the preparational steps the unification was simple.
The linux_prom_pci_registers definition did not look like
it could be unified at first look since the structure is assigned
using prop_getproperty() / of_get_property() so the structure
is assumed to come direct form the prom.
The LINUX_OPPROM_MAGIC was kept even if it is not used by the kernel
on the assumption that userspace may require it.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Trivial unification where the sparc64 specific
parts are protected using a signle ifdef/endif pair.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The two ptrace.h implementations are very alike but
the small differences required two set of ifdef/else/endif pairs.
The definition of reg_window32 could have been shared but
that would have required several updates in sparc32 code as
all printk formatting for example assume it is longs.
sparc_stackf looked like anohter candidate to share if the 32
bit was renamed to sparc_stackf32.
But it contains two pointers in the sparc32 version which would
have been 64 bit in the sparc64 version so it was non-trivial.
Using a set of accessor macros could do the trick if pursued later.
The sparc64 specific definitions are not protected by
ifdef - as it should not be required to do so.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the renamed types in place the unification was straightforward.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
They were almost identical and with the preapration
patch nothing was needed to be added.
The unified version contains a few sparc64 only definitions
but they are kept as is and not protected by ifdef/endif.
The unified version exports a bit more to userspace then the
32 bit version did.
This is not considered fatal.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
To my suprise struct stat64 was not equal on sparc 32 and sparc64,
so there was really nothing to share here.
Unify the files by adding their respective content to stat.h.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The posix types differed so much in their definition
that they are kept in separate blocks.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is complicated a little because compat_audit.c wants to see only
the 32bit syscall numbers, but is being built in a 64bit compile.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This has been marked BROKEN for a long time and it's more likely
to get rewritten from scratch than to be fixed up and made usable.
Signed-off-by: David S. Miller <davem@davemloft.net>
The majority of this patch was created by the following script:
***
ASM=arch/sparc/include/asm
mkdir -p $ASM
git mv include/asm-sparc64/ftrace.h $ASM
git rm include/asm-sparc64/*
git mv include/asm-sparc/* $ASM
sed -ie 's/asm-sparc64/asm/g' $ASM/*
sed -ie 's/asm-sparc/asm/g' $ASM/*
***
The rest was an update of the top-level Makefile to use sparc
for header files when sparc64 is being build.
And a small fixlet to pick up the correct unistd.h from
sparc64 code.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Linus Torvalds