Commit Graph

36 Commits

Author SHA1 Message Date
Hugh Dickins
b462705ac6 [PATCH] mm: arches skip ptlock
Convert those few architectures which are calling pud_alloc, pmd_alloc,
pte_alloc_map on a user mm, not to take the page_table_lock first, nor drop it
after.  Each of these can continue to use pte_alloc_map, no need to change
over to pte_alloc_map_lock, they're neither racy nor swappable.

In the sparc64 io_remap_pfn_range, flush_tlb_range then falls outside of the
page_table_lock: that's okay, on sparc64 it's like flush_tlb_mm, and that has
always been called from outside of page_table_lock in dup_mmap.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 21:40:40 -07:00
Nick Piggin
b5810039a5 [PATCH] core remove PageReserved
Remove PageReserved() calls from core code by tightening VM_RESERVED
handling in mm/ to cover PageReserved functionality.

PageReserved special casing is removed from get_page and put_page.

All setting and clearing of PageReserved is retained, and it is now flagged
in the page_alloc checks to help ensure we don't introduce any refcount
based freeing of Reserved pages.

MAP_PRIVATE, PROT_WRITE of VM_RESERVED regions is tentatively being
deprecated.  We never completely handled it correctly anyway, and is be
reintroduced in future if required (Hugh has a proof of concept).

Once PageReserved() calls are removed from kernel/power/swsusp.c, and all
arch/ and driver code, the Set and Clear calls, and the PG_reserved bit can
be trivially removed.

Last real user of PageReserved is swsusp, which uses PageReserved to
determine whether a struct page points to valid memory or not.  This still
needs to be addressed (a generic page_is_ram() should work).

A last caveat: the ZERO_PAGE is now refcounted and managed with rmap (and
thus mapcounted and count towards shared rss).  These writes to the struct
page could cause excessive cacheline bouncing on big systems.  There are a
number of ways this could be addressed if it is an issue.

Signed-off-by: Nick Piggin <npiggin@suse.de>

Refcount bug fix for filemap_xip.c

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 21:40:39 -07:00
Hugh Dickins
fc2acab31b [PATCH] mm: tlb_finish_mmu forget rss
zap_pte_range has been counting the pages it frees in tlb->freed, then
tlb_finish_mmu has used that to update the mm's rss.  That got stranger when I
added anon_rss, yet updated it by a different route; and stranger when rss and
anon_rss became mm_counters with special access macros.  And it would no
longer be viable if we're relying on page_table_lock to stabilize the
mm_counter, but calling tlb_finish_mmu outside that lock.

Remove the mmu_gather's freed field, let tlb_finish_mmu stick to its own
business, just decrement the rss mm_counter in zap_pte_range (yes, there was
some point to batching the update, and a subsequent patch restores that).  And
forget the anal paranoia of first reading the counter to avoid going negative
- if rss does go negative, just fix that bug.

Remove the mmu_gather's flushes and avoided_flushes from arm and arm26: no use
was being made of them.  But arm26 alone was actually using the freed, in the
way some others use need_flush: give it a need_flush.  arm26 seems to prefer
spaces to tabs here: respect that.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 21:40:37 -07:00
Hugh Dickins
4d6ddfa924 [PATCH] mm: tlb_is_full_mm was obscure
tlb_is_full_mm?  What does that mean?  The TLB is full?  No, it means that the
mm's last user has gone and the whole mm is being torn down.  And it's an
inline function because sparc64 uses a different (slightly better)
"tlb_frozen" name for the flag others call "fullmm".

And now the ptep_get_and_clear_full macro used in zap_pte_range refers
directly to tlb->fullmm, which would be wrong for sparc64.  Rather than
correct that, I'd prefer to scrap tlb_is_full_mm altogether, and change
sparc64 to just use the same poor name as everyone else - is that okay?

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 21:40:37 -07:00
David S. Miller
b4d1b82578 [SPARC64]: Fix powering off on SMP.
Doing a "SUNW,stop-self" firmware call on the other cpus is not the
correct thing to do when dropping into the firmware for a halt,
reboot, or power-off.

For now, just do nothing to quiet the other cpus, as the system should
be quiescent enough.  Later we may decide to implement smp_send_stop()
like the other SMP platforms do.

Based upon a report from Christopher Zimmermann.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-14 15:26:08 -07:00
David S. Miller
c9c1083074 [SPARC64]: Fix boot failures on SunBlade-150
The sequence to move over to the Linux trap tables from
the firmware ones needs to be more air tight.  It turns
out that to be %100 safe we do need to be able to translate
OBP mappings in our TLB miss handlers early.

In order not to eat up a lot of kernel image memory with
static page tables, just use the translations array in
the OBP TLB miss handlers.  That solves the bulk of the
problem.

Furthermore, to make sure the OBP TLB miss path will work
even before the fixed MMU globals are loaded, explicitly
load %g1 to TLB_SFSR at the beginning of the i-TLB and
d-TLB miss handlers.

To ease the OBP TLB miss walking of the prom_trans[] array,
we sort it then delete all of the non-OBP entries in there
(for example, there are entries for the kernel image itself
which we're not interested in at all).

We also save about 32K of kernel image size with this change.
Not a bad side effect :-)

There are still some reasons why trampoline.S can't use the
setup_trap_table() yet.  The most noteworthy are:

1) OBP boots secondary processors with non-bias'd stack for
   some reason.  This is easily fixed by using a small bootup
   stack in the kernel image explicitly for this purpose.

2) Doing a firmware call via the normal C call prom_set_trap_table()
   goes through the whole OBP enter/exit sequence that saves and
   restores OBP and Linux kernel state in the MMUs.  This path
   unfortunately does a "flush %g6" while loading up the OBP locked
   TLB entries for the firmware call.

   If we setup the %g6 in the trampoline.S code properly, that
   is in the PAGE_OFFSET linear mapping, but we're not on the
   kernel trap table yet so those addresses won't translate properly.

   One idea is to do a by-hand firmware call like we do in the
   early bootup code and elsewhere here in trampoline.S  But this
   fails as well, as aparently the secondary processors are not
   booted with OBP's special locked TLB entries loaded.  These
   are necessary for the firwmare to processes TLB misses correctly
   up until the point where we take over the trap table.

This does need to be resolved at some point.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-12 12:22:46 -07:00
David S. Miller
9ad98c5b44 [SPARC64]: Fix initrd when net booting.
By allocating early memory for the firmware page tables, we
can write over the beginning of the initrd image.

So what we do now is:

1) Read in firmware translations table while still on the
   firmware's trap table.
2) Switch to Linux trap table.
3) Init bootmem.
4) Build firmware page tables using __alloc_bootmem().

And this keeps the initrd from being clobbered.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-05 15:12:00 -07:00
David S. Miller
0835ae0f27 [SPARC64]: Replace cheetah+ code patching with variables.
Instead of code patching to handle the page size fields in
the context registers, just use variables from which we get
the proper values.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-04 15:23:20 -07:00
David S. Miller
13edad7a5c [SPARC64]: Rewrite convoluted physical memory probing.
Delete all of the code working with sp_banks[] and replace
with clean acquisition and sorting of physical memory
parameters from the firmware.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-29 17:58:26 -07:00
David S. Miller
10147570f9 [SPARC64]: Kill all external references to sp_banks[]
Thus, we can mark sp_banks[] static in arch/sparc64/mm/init.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-28 21:46:43 -07:00
David S. Miller
0836a0eb40 [SPARC64]: Move phys_base, kern_{base,size}, and sp_banks[] init to paging_init
Also, move prom_probe_memory() into arch/sparc64/mm/init.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-28 21:38:08 -07:00
David S. Miller
efdc1e2083 [SPARC64]: Simplify user fault fixup handling.
Instead of doing byte-at-a-time user accesses to figure
out where the fault occurred, read the saved fault_address
from the current thread structure.

For the sake of defensive programming, if the fault_address
does not fall into the user buffer range, simply assume the
whole area faulted.  This will cause the fixup for
copy_from_user() to clear the entire kernel side buffer.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-28 21:06:47 -07:00
David S. Miller
8cf14af0a7 [SPARC64]: Convert to use generic exception table support.
The funny "range" exception table entries we had were only
used by the compat layer socketcall assembly, and it wasn't
even needed there.

For free we now get proper exception table sorting and fast
binary searching.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-28 20:21:11 -07:00
David S. Miller
0dc4610698 [SPARC64]: Do not do TLB pre-filling any more.
In order to do it correctly on UltraSPARC-III+ and later we'd
need to add some complicated code to set the TAG access extension
register before loading the TLB.

Since this optimization gives questionable gains, it's best to
just remove it for now instead of adding the fix for Ultra-III+

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-26 16:12:18 -07:00
David S. Miller
c5bd50a953 [SPARC64]: Simplify Spitfire D-cache page flush.
It tries to batch up the tag loads and comparisons, and
then the stores.  And this is just complicated instead
of efficient.

Also, make the symbol of the Cheetah version more grepable.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-26 16:06:03 -07:00
David S. Miller
5642530651 [SPARC64]: Add CONFIG_DEBUG_PAGEALLOC support.
The trick is that we do the kernel linear mapping TLB miss starting
with an instruction sequence like this:

	ba,pt		%xcc, kvmap_load
	 xor		%g2, %g4, %g5

succeeded by an instruction sequence which performs a full page table
walk starting at swapper_pg_dir.

We first take over the trap table from the firmware.  Then, using this
constant PTE generation for the linear mapping area above, we build
the kernel page tables for the linear mapping.

After this is setup, we patch that branch above into a "nop", which
will cause TLB misses to fall through to the full page table walk.

With this, the page unmapping for CONFIG_DEBUG_PAGEALLOC is trivial.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-25 16:46:57 -07:00
David S. Miller
898cf0ecb7 [SPARC64]: Mark functions called by paging_init() as __init.
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-23 11:59:44 -07:00
David S. Miller
bff06d5522 [SPARC64]: Rewrite bootup sequence.
Instead of all of this cpu-specific code to remap the kernel
to the correct location, use portable firmware calls to do
this instead.

What we do now is the following in position independant
assembler:

	chosen_node = prom_finddevice("/chosen");
	prom_mmu_ihandle_cache = prom_getint(chosen_node, "mmu");
	vaddr = 4MB_ALIGN(current_text_addr());
	prom_translate(vaddr, &paddr_high, &paddr_low, &mode);
	prom_boot_mapping_mode = mode;
	prom_boot_mapping_phys_high = paddr_high;
	prom_boot_mapping_phys_low = paddr_low;
	prom_map(-1, 8 * 1024 * 1024, KERNBASE, paddr_low);

and that replaces the massive amount of by-hand TLB probing and
programming we used to do here.

The new code should also handle properly the case where the kernel
is mapped at the correct address already (think: future kexec
support).

Consequently, the bulk of remap_kernel() dies as does the entirety
of arch/sparc64/prom/map.S

We try to share some strings in the PROM library with the ones used
at bootup, and while we're here mark input strings to oplib.h routines
with "const" when appropriate.

There are many more simplifications now possible.  For one thing, we
can consolidate the two copies we now have of a lot of cpu setup code
sitting in head.S and trampoline.S.

This is a significant step towards CONFIG_DEBUG_PAGEALLOC support.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-22 20:11:33 -07:00
David S. Miller
40fd3533c9 [SPARC64]: Kill readjust_prom_translations()
Testing shows that the prom_unmap() calls do absolutely
nothing.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-22 13:03:36 -07:00
David S. Miller
2bdb3cb265 [SPARC64]: Remove unnecessary paging_init() cruft.
Because we don't access the PAGE_OFFSET linear mappings
any longer before we take over the trap table from the
firmware, we don't need to load dummy mappings there
into the TLB and we don't need the bootmap_base hack
any longer either.

While we are here, check for a larger than 8MB kernel
and halt the boot with an error message.  We know that
doesn't work, so instead of failing mysteriously we
should let the user know exactly what's wrong.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-22 01:08:57 -07:00
David S. Miller
5085b4a549 [SPARC64]: Do not allocate OBP page tables using bootmem
Just allocate them physically starting from the end of
the kernel image.  This incredibly simplifies our MM
bootstrap in that we don't need any mappings in the linear
PAGE_OFFSET area working in order to bootstrap ourselves and
take over the trap table from the firmware.

Many further simplifications are possible now, and this also
sets the stage for CONFIG_DEBUG_PAGEALLOC support.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-22 00:45:41 -07:00
David S. Miller
405599bd98 [SPARC64]: Break up inherit_prom_mappings() into it's constituent parts.
This thing was just a huge monolithic mess, so chop it up.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-22 00:12:35 -07:00
David S. Miller
b206fc4c09 [SPARC64]: Do not allocate prom translations using bootmem.
Use __initdata instead.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-21 22:31:13 -07:00
David S. Miller
1ac4f5ebaa [SPARC64]: Remove ktlb.S instruction patching.
This was kind of ugly, and actually buggy.  The bug was that
we didn't handle a machine with memory starting > 4GB.  If
the 'prompmd' was allocated in physical memory > 4GB we'd
croak because the obp_iaddr_patch and obp_daddr_patch things
only supported a 32-bit physical address.

So fix this by just loading the appropriate values from two
variables in the kernel image, which is locked into the TLB
and thus accesses to them can't cause a recursive TLB miss.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-21 21:49:32 -07:00
Prasanna S Panchamukhi
83005161c8 [PATCH] kprobes-prevent-possible-race-conditions-sparc64-changes fix
This patch adds flags "ax" to .kprobe.text section.

Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:58:00 -07:00
Prasanna S Panchamukhi
05e14cb3ba [PATCH] Kprobes: prevent possible race conditions sparc64 changes
This patch contains the sparc64 architecture specific changes to prevent the
possible race conditions.

Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:58:00 -07:00
David S. Miller
a7a6cac204 [SPARC]: Kill io_remap_page_range()
It's been deprecated long enough and there are no in-tree
users any longer.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-01 21:51:26 -07:00
David S. Miller
2ef27778a2 [SPARC64]: Preserve nucleus ctx page size during TLB flushes.
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-30 20:21:34 -07:00
David S. Miller
48b0e5487f [SPARC64]: Fix ugly dependency on NR_CPUS being a power-of-2.
The page->flags D-cache dirty state tracking depended upon
NR_CPUS being a power-of-2 via it's "NR_CPUS - 1" masking.

Fix that to use a fixed (256 - 1) mask as that is the limit
imposed by thread_info->cpu which is a "u8".

Finally, add a compile time check that NR_CPUS is not greater
than 256.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-27 16:08:44 -07:00
David S. Miller
af166d15c3 [SPARC64]: Kill ancient and unused SYSCALL_TRACING debugging code.
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-10 15:56:40 -07:00
David S. Miller
fef43da4e4 [SPARC64]: Fix UltraSPARC-III fallout from membar changes.
The membar changes made the size of __cheetah_flush_tlb_pending
grow by one instruction, but the boot-time code patching was
not updated to match.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 19:45:24 -07:00
David S. Miller
b445e26cbf [SPARC64]: Avoid membar instructions in delay slots.
In particular, avoid membar instructions in the delay
slot of a jmpl instruction.

UltraSPARC-I, II, IIi, and IIe have a bug, documented in
the UltraSPARC-IIi User's Manual, Appendix K, Erratum 51

The long and short of it is that if the IMU unit misses
on a branch or jmpl, and there is a store buffer synchronizing
membar in the delay slot, the chip can stop fetching instructions.

If interrupts are enabled or some other trap is enabled, the
chip will unwedge itself, but performance will suffer.

We already had a workaround for this bug in a few spots, but
it's better to have the entire tree sanitized for this rule.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-27 15:42:04 -07:00
David Gibson
63551ae0fe [PATCH] Hugepage consolidation
A lot of the code in arch/*/mm/hugetlbpage.c is quite similar.  This patch
attempts to consolidate a lot of the code across the arch's, putting the
combined version in mm/hugetlb.c.  There are a couple of uglyish hacks in
order to covert all the hugepage archs, but the result is a very large
reduction in the total amount of code.  It also means things like hugepage
lazy allocation could be implemented in one place, instead of six.

Tested, at least a little, on ppc64, i386 and x86_64.

Notes:
	- this patch changes the meaning of set_huge_pte() to be more
	  analagous to set_pte()
	- does SH4 need s special huge_ptep_get_and_clear()??

Acked-by: William Lee Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:15 -07:00
Christoph Hellwig
8edf72ebce [SPARC64]: Kill useless __pte_alloc_one_kernel indirection
warning: untested, but it there's not too much chance for screwups

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-05 14:27:56 -07:00
David S. Miller
a9546f59e9 [PATCH] sparc64: Do not flush dcache for ZERO_PAGE.
This case actually can get exercised a lot during an ELF
coredump of a process which contains a lot of non-COW'd
anonymous pages.  GDB has this test case which in partiaular
creates near terabyte process full of ZERO_PAGEes.  It takes
forever to just walk through the page tables because of
all of these spurious cache flushes on sparc64.

With this change it takes only a second or so.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-17 18:03:09 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
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!
2005-04-16 15:20:36 -07:00