Commit Graph

8 Commits

Author SHA1 Message Date
Jan Beulich a3c6018e56 x86: fix assumed to be contiguous leaf page tables for kmap_atomic region (take 2)
Debugging and original patch from Nick Piggin <npiggin@suse.de>

The early fixmap pmd entry inserted at the very top of the KVA is causing the
subsequent fixmap mapping code to not provide physically linear pte pages over
the kmap atomic portion of the fixmap (which relies on said property to
calculate pte addresses).

This has caused weird boot failures in kmap_atomic much later in the boot
process (initial userspace faults) on a 32-bit PAE system with a larger number
of CPUs (smaller CPU counts tend not to run over into the next page so don't
show up the problem).

Solve this by attempting to clear out the page table, and copy any of its
entries to the new one. Also, add a bug if a nonlinear condition is encountered
and can't be resolved, which might save some hours of debugging if this fragile
scheme ever breaks again...

Once we have such logic, we can also use it to eliminate the early ioremap
trickery around the page table setup for the fixmap area. This also fixes
potential issues with FIX_* entries sharing the leaf page table with the early
ioremap ones getting discarded by early_ioremap_clear() and not restored by
early_ioremap_reset(). It at once eliminates the temporary (and configuration,
namely NR_CPUS, dependent) unavailability of early fixed mappings during the
time the fixmap area page tables get constructed.

Finally, also replace the hard coded calculation of the initial table space
needed for the fixmap area with a proper one, allowing kernels configured for
large CPU counts to actually boot.

Based-on: Nick Piggin <npiggin@suse.de>
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-16 13:47:04 +01:00
FUJITA Tomonori 181de82ee3 x86: remove dead BIO_VMERGE_BOUNDARY definition
Impact: cleanup, remove dead code

The block layer dropped the virtual merge feature
(b8b3e16cfe).

BIO_VMERGE_BOUNDARY definition is meaningless now.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-03 08:26:40 +01:00
Ingo Molnar 93093d099e x86: provide readq()/writeq() on 32-bit too, complete
if HAVE_READQ/HAVE_WRITEQ are defined, the full range of readq/writeq
APIs has to be provided to drivers:

 drivers/infiniband/hw/amso1100/c2.c: In function 'c2_tx_ring_alloc':
 drivers/infiniband/hw/amso1100/c2.c:133: error: implicit declaration of function '__raw_writeq'

So provide them on 32-bit as well. Also, map all the APIs to the
strongest ordering variant. It's way too easy to mess such details
up in drivers and the difference between "memory" and "" constrained
asm() constructs is in the noise range.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-30 10:26:18 +01:00
Ingo Molnar a0b1131e47 x86: provide readq()/writeq() on 32-bit too, cleanup
Impact: cleanup

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-30 09:38:19 +01:00
Hitoshi Mitake 2c5643b1c5 x86: provide readq()/writeq() on 32-bit too
Impact: add new API for drivers

Add implementation of readq/writeq to x86_32, and add config value to
the x86 architecture to determine existence of readq/writeq.

Signed-off-by: Hitoshi Mitake <h.mitake@gmail.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-30 09:38:16 +01:00
Harvey Harrison 1d6cf1feb8 x86: start annotating early ioremap pointers with __iomem
Impact: some new sparse warnings in e820.c etc, but no functional change.

As with regular ioremap, iounmap etc, annotate with __iomem.

Fixes the following sparse warnings, will produce some new ones
elsewhere in arch/x86 that will get worked out over time.

arch/x86/mm/ioremap.c:402:9: warning: cast removes address space of expression
arch/x86/mm/ioremap.c:406:10: warning: cast adds address space to expression (<asn:2>)
arch/x86/mm/ioremap.c:782:19: warning: Using plain integer as NULL pointer

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-29 08:05:14 +01:00
H. Peter Anvin 1965aae3c9 x86: Fix ASM_X86__ header guards
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:

a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:23 -07:00
Al Viro bb8985586b x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:20 -07:00