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2008-07-17sparc/mm/: possible cleanupsAdrian Bunk
This patch contains the following possible cleanups: - make the following needlessly global code static: - fault.c: force_user_fault() - init.c: calc_max_low_pfn() - init.c: pgt_cache_water[] - init.c: map_high_region() - srmmu.c: hwbug_bitmask - srmmu.c: srmmu_swapper_pg_dir - srmmu.c: srmmu_context_table - srmmu.c: is_hypersparc - srmmu.c: srmmu_cache_pagetables - srmmu.c: srmmu_nocache_size - srmmu.c: srmmu_nocache_end - srmmu.c: srmmu_get_nocache() - srmmu.c: srmmu_free_nocache() - srmmu.c: srmmu_early_allocate_ptable_skeleton() - srmmu.c: srmmu_nocache_calcsize() - srmmu.c: srmmu_nocache_init() - srmmu.c: srmmu_alloc_thread_info() - srmmu.c: early_pgtable_allocfail() - srmmu.c: srmmu_early_allocate_ptable_skeleton() - srmmu.c: srmmu_allocate_ptable_skeleton() - srmmu.c: srmmu_inherit_prom_mappings() - sunami.S: tsunami_copy_1page - remove the following unused code: - init.c: struct sparc_aliases Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17sparc/kernel/: possible cleanupsAdrian Bunk
This patch contains the following possible cleanups: - make the following needlessly global code static: - apc.c: apc_swift_idle() - ebus.c: ebus_blacklist_irq() - ebus.c: fill_ebus_child() - ebus.c: fill_ebus_device() - entry.S: syscall_is_too_hard - etra: tsetup_sun4c_stackchk - head.S: cputyp - head.S: prom_vector_p - idprom.c: Sun_Machines[] - ioport.c: _sparc_find_resource() - ioport.c: create_proc_read_entry() - irq.c: struct sparc_irq[] - rtrap.S: sun4c_rett_stackchk - setup.c: prom_sync_me() - setup.c: boot_flags - sun4c_irq.c: sun4c_sbint_to_irq() - sun4d_irq.c: sbus_tid[] - sun4d_irq.c: struct sbus_actions - sun4d_irq.c: sun4d_sbint_to_irq() - sun4m_irq.c: sun4m_sbint_to_irq() - sun4m_irq.c: sun4m_get_irqmask() - sun4m_irq.c: sun4m_timers - sun4m_smp.c: smp4m_cross_call() - sun4m_smp.c: smp4m_blackbox_id() - sun4m_smp.c: smp4m_blackbox_current() - time.c: sp_clock_typ - time.c: sbus_time_init() - traps.c: instruction_dump() - wof.S: spwin_sun4c_stackchk - wuf.S: sun4c_fwin_stackchk - #if 0 the following unused code: - process.c: sparc_backtrace_lock - process.c: __show_backtrace() - process.c: show_backtrace() - process.c: smp_show_backtrace_all_cpus() - remove the following unused code: - entry.S: __handle_exception - smp.c: smp_num_cpus - smp.c: smp_activated - smp.c: __cpu_number_map[] - smp.c: __cpu_logical_map[] - smp.c: bitops_spinlock - traps.c: trap_curbuf - traps.c: trapbuf[] - traps.c: linux_smp_still_initting - traps.c: thiscpus_tbr - traps.c: thiscpus_mid Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-14Merge commit 'v2.6.26' into bkl-removalJonathan Corbet
2008-07-02sparc-apc: BKL pushdownArnd Bergmann
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2008-06-03sparc: switch /proc/led to seq_fileAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-20sparc: remove CVS keywordsAdrian Bunk
This patch removes the CVS keywords that weren't updated for a long time from comments. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-16[PATCH] take init_files to fs/file.cAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-05-12sparc: Fix mremap address range validation.David S. Miller
Just like mmap, we need to validate address ranges regardless of MAP_FIXED. sparc{,64}_mmap_check()'s flag argument is unused, remove. Based upon a report and preliminary patch by Jan Lieskovsky <jlieskov@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-11sparc32: fix rtrap.S typoRobert Reif
Fix compile problem in rtrap.S arch/sparc/kernel/built-in.o: In function `ret_trap_userwins_ok': arch/sparc/kernel/rtrap.S:(.text+0x1900): undefined reference to `PSR_SYCALL' Signed-off-by: Robert Reif <reif@earthlink.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-11sparc: Fix debugger syscall restart interactions.David S. Miller
So, forever, we've had this ptrace_signal_deliver implementation which tries to handle all of the nasties that can occur when the debugger looks at a process about to take a signal. It's meant to address all of these issues inside of the kernel so that the debugger need not be mindful of such things. Problem is, this doesn't work. The idea was that we should do the syscall restart business first, so that the debugger captures that state. Otherwise, if the debugger for example saves the child's state, makes the child execute something else, then restores the saved state, we won't handle the syscall restart properly because we lose the "we're in a syscall" state. The code here worked for most cases, but if the debugger actually passes the signal through to the child unaltered, it's possible that we would do a syscall restart when we shouldn't have. In particular this breaks the case of debugging a process under a gdb which is being debugged by yet another gdb. gdb uses sigsuspend to wait for SIGCHLD of the inferior, but if gdb itself is being debugged by a top-level gdb we get a ptrace_stop(). The top-level gdb does a PTRACE_CONT with SIGCHLD to let the inferior gdb see the signal. But ptrace_signal_deliver() assumed the debugger would cancel out the signal and therefore did a syscall restart, because the return error was ERESTARTNOHAND. Fix this by simply making ptrace_signal_deliver() a nop, and providing a way for the debugger to control system call restarting properly: 1) Report a "in syscall" software bit in regs->{tstate,psr}. It is set early on in trap entry to a system call and is fully visible to the debugger via ptrace() and regsets. 2) Test this bit right before doing a syscall restart. We have to do a final recheck right after get_signal_to_deliver() in case the debugger cleared the bit during ptrace_stop(). 3) Clear the bit in trap return so we don't accidently try to set that bit in the real register. As a result we also get a ptrace_{is,clear}_syscall() for sparc32 just like sparc64 has. M68K has this same exact bug, and is now the only other user of the ptrace_signal_deliver hook. It needs to be fixed in the same exact way as sparc. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-11sparc: Fix ptrace() detach.David S. Miller
Forever we had a PTRACE_SUNOS_DETACH which was unconditionally recognized, regardless of the personality of the process. Unfortunately, this value is what ended up in the GLIBC sys/ptrace.h header file on sparc as PTRACE_DETACH and PT_DETACH. So continue to recognize this old value. Luckily, it doesn't conflict with anything we actually care about. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-10sparc32: Don't twiddle PT_DTRACE in exec.David S. Miller
That bit isn't used on this platform. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-07sparc: Fix SA_ONSTACK signal handling.David S. Miller
We need to be more liberal about the alignment of the buffer given to us by sigaltstack(). The user should not need to be mindful of all of the alignment constraints we have for the stack frame. This mirrors how we handle this situation in clone() as well. Also, we align the stack even in non-SA_ONSTACK cases so that signals due to bad stack alignment can be delivered properly. This makes such errors easier to debug and recover from. Finally, add the sanity check x86 has to make sure we won't overflow the signal stack. This fixes glibc testcases nptl/tst-cancel20.c and nptl/tst-cancelx20.c Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-07sparc: Fix fork/clone/vfork system call restart.David S. Miller
We clobber %i1 as well as %i0 for these system calls, because they give two return values. Therefore, on error, we have to restore %i1 properly or else the restart explodes since it uses the wrong arguments. This fixes glibc's nptl/tst-eintr1.c testcase. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-07sparc: Fix mmap VA span checking.David S. Miller
We should not conditionalize VA range checks on MAP_FIXED. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-02sparc32: Delete prom_stdin and prom_stdout.David S. Miller
They are written, but never used. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-02sparc32: More memory probing consolidation.David S. Miller
The PROM library function prom_meminit() builds a table, prom_phys_avail[], just so that probe_memory() in arch/sparc/mm/fault.c can copy it into sp_banks[]. Just have prom_meminit() fill in the sp_banks[] array directly, and remove duplicated sort() function. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-02sparc32: Kill totally unused memory information tables.David S. Miller
The code in arch/sparc/prom/memory.c computes three tables, the list of total memory, the list of available memory (total minus what firmware is using), and the list of firmware taken memory. Only the available memory list is even used. Therefore, kill those unused tables and make prom_meminfo() return just the available memory list. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: sparc64: remove duplicated include sparc: Add kgdb support. kgdbts: Sparc needs sstep emulation. sparc32: Kill smp_message_pass() and related code. sparc64: Kill PIL_RESERVED, unused. sparc64: Split entry.S up into seperate files.
2008-04-29sparc: Add kgdb support.David S. Miller
Current limitations: 1) On SMP single stepping has some fundamental issues, shared with other sw single-step architectures such as mips and arm. 2) On 32-bit sparc we don't support SMP kgdb yet. That requires some reworking of the IPI mechanisms and infrastructure on that platform. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-29sparc32: Kill smp_message_pass() and related code.David S. Miller
Completely unused, and it just makes the SMP message passing code on 32-bit sparc look more complex than it is. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-27sparc: Remove old style signal frame support.David S. Miller
Back around the same time we were bootstrapping the first 32-bit sparc Linux kernel with a SunOS userland, we made the signal frame match that of SunOS. By the time we even started putting together a native Linux userland for 32-bit Sparc we realized this layout wasn't sufficient for Linux's needs. Therefore we changed the layout, yet kept support for the old style signal frame layout in there. The detection mechanism is that we had sys_sigaction() start passing in a negative signal number to indicate "new style signal frames please". Anyways, no binaries exist in the world that use the old stuff. In fact, I bet Jakub Jelinek and myself are the only two people who ever had such binaries to be honest. So let's get rid of this stuff. I added an assertion using WARN_ON_ONCE() that makes sure 32-bit applications are passing in that negative signal number still. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-23sparc: cleanup after SunOS binary emulation removalAdrian Bunk
The following cleanups are now possible: - arch/sparc/kernel/entry.S:ret_sys_call no longer has to be global - arch/sparc/kernel/signal.c:sys_sigpause() can be removed Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: [SPARC]: Remove SunOS and Solaris binary support.
2008-04-21[SPARC]: Remove SunOS and Solaris binary support.David S. Miller
As per Documentation/feature-removal-schedule.txt Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-20[SPARC] minor irq handler cleanupsJeff Garzik
- mark timer_interrupt() static - sparc_floppy_request_irq() prototype should use irq_handler_t Signed-off-by: Jeff Garzik <jgarzik@redhat.com> Acked-by: David S. Miller <davem@davemloft.net>
2008-04-17Generic semaphore implementationMatthew Wilcox
Semaphores are no longer performance-critical, so a generic C implementation is better for maintainability, debuggability and extensibility. Thanks to Peter Zijlstra for fixing the lockdep warning. Thanks to Harvey Harrison for pointing out that the unlikely() was unnecessary. Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Acked-by: Ingo Molnar <mingo@elte.hu>
2008-04-29sparc: Export symbols for ZERO_PAGE usage in modules.Aneesh Kumar K.V
ext4 uses ZERO_PAGE(0) to zero out blocks. We need to export different symbols in different arches for the usage of ZERO_PAGE in modules. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-04-29sparc: use kbuild.h instead of defining macros in asm-offsets.cChristoph Lameter
Signed-off-by: Christoph Lameter <clameter@sgi.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29iomap: fix 64 bits resources on 32 bitsBenjamin Herrenschmidt
Almost all implementations of pci_iomap() in the kernel, including the generic lib/iomap.c one, copies the content of a struct resource into unsigned long's which will break on 32 bits platforms with 64 bits resources. This fixes all definitions of pci_iomap() to use resource_size_t. I also "fixed" the 64bits arch for consistency. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-09[SPARC]: Fix several regset and ptrace bugs.David S. Miller
1) ptrace should pass 'current' to task_user_regset_view() 2) When fetching general registers using a 64-bit view, and the target is 32-bit, we have to convert. 3) Skip the whole register window get/set code block if the user isn't asking to access anything in there. Otherwise we have problems if the user doesn't have an address space setup. Fetching ptrace register is still valid at such a time, and ptrace does not try to access the register window area of the regset. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-17Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
2008-03-17[NET] endianness noise: INADDR_ANYAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-03[SPARC]: Fix link errors with gcc-4.3David S. Miller
Reported by Adrian Bunk. Just like in changeset a3f9985843b674cbcb58f39fab8416675e7ab842 ("[SPARC64]: Move kernel unaligned trap handlers into assembler file.") we have to move the assembler bits into a seperate asm file because as far as the compiler is concerned these inline bits we're doing in unaligned.c are unreachable. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-03sparc: replace remaining __FUNCTION__ occurancesHarvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-28[SPARC]: Add reboot_command[] extern decl to asm/system.hDavid S. Miller
Kill off some sparse warnings. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-28[SPARC]: Mark linux_sparc_{fpu,chips} static.David S. Miller
Caught by sparse. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-24[SPARC]: Fix build in arch/sparc/kernel/led.cDavid S. Miller
CC [M] arch/sparc/kernel/led.o arch/sparc/kernel/led.c: In function 'led_blink': arch/sparc/kernel/led.c:35: error: invalid use of undefined type 'struct timer_list' arch/sparc/kernel/led.c:35: error: 'jiffies' undeclared (first use in this function) arch/sparc/kernel/led.c:35: error: (Each undeclared identifier is reported only once arch/sparc/kernel/led.c:35: error: for each function it appears in.) arch/sparc/kernel/led.c:36: error: 'avenrun' undeclared (first use in this function) arch/sparc/kernel/led.c:36: error: 'FSHIFT' undeclared (first use in this function) arch/sparc/kernel/led.c:36: error: 'HZ' undeclared (first use in this function) arch/sparc/kernel/led.c:37: error: invalid use of undefined type 'struct timer_list' arch/sparc/kernel/led.c:39: error: invalid use of undefined type 'struct timer_list' arch/sparc/kernel/led.c:40: error: invalid use of undefined type 'struct timer_list' arch/sparc/kernel/led.c:42: error: implicit declaration of function 'add_timer' arch/sparc/kernel/led.c: In function 'led_write_proc': arch/sparc/kernel/led.c:70: error: implicit declaration of function 'copy_from_user' arch/sparc/kernel/led.c:84: error: implicit declaration of function 'del_timer_sync' arch/sparc/kernel/led.c: In function 'led_init': arch/sparc/kernel/led.c:109: error: implicit declaration of function 'init_timer' arch/sparc/kernel/led.c:110: error: invalid use of undefined type 'struct timer_list' make[1]: *** [arch/sparc/kernel/led.o] Error 1 Based upon original patch by Robert Reif. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: [SPARC64]: Add regs_return_value(). [SPARC64]: Kill pcic_present(). [SPARC]: Kill 'prom_palette'. [ATYFB]: Kill 'prom_palette' sparc code. [SPARC64]: Kill 'prom_keyboard'. [SPARC]: Kill extern decl of 'panic_setup'. [SPARC64]: Delete 'boot_flags'. [SPARC64]: Kill unused function 'kernel_enter_debugger'. [SPARC64] arch/sparc64/kernel/unaligned.c: Use time_* macros [SPARC64]: Always register a PROM based early console. [SPARC64]: Update defconfig. [SPARC64]: Add -mtune=ultrasparc3 if possible. [SPARC64]: Remove Makefile code for ancient gcc and binutils. [SPARC64]: Remove DEBUG_BOOTMEM. [SPARC64]: Use shorter "get_zeroed_page" call. [SPARC]: Use shorter form of "get_zeroed_page". [SPARC]: video/cg14.c and video/sbuslib.c build fixes
2008-02-18[SPARC]: Kill 'prom_palette'.David S. Miller
The idea of this thing is we could save/restore the firmware's palette when breaking in and out of the firmware prompt. Only one driver implemented this (atyfb) and it's value is questionable. If you're just debugging you don't really care that the characters end up being purple or whatever. And we can provide better debugging and firmware command facilities with minimal in-kernel console I/O drivers. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-18[SPARC]: Kill extern decl of 'panic_setup'.David S. Miller
This was made static in kernel/panic.c a long time ago. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-13xtime_lock vs update_process_timesPeter Zijlstra
Commit d3d74453c34f8fd87674a8cf5b8a327c68f22e99 ("hrtimer: fixup the HRTIMER_CB_IRQSAFE_NO_SOFTIRQ fallback") broke several archs, and since only Russell bothered to merge the fix, and Greg to ACK his arch, I'm sending this for merger. I have confirmation that the Alpha bit results in a booting kernel. That leaves: blackfin, frv, sh and sparc untested. The deadlock in question was found by Russell: IRQ handle -> timer_tick() - xtime seqlock held for write -> update_process_times() -> run_local_timers() -> hrtimer_run_queues() -> hrtimer_get_softirq_time() - tries to get a read lock Now, Thomas assures me the fix is trivial, only do_timer() needs to be done under the xtime_lock, and update_process_times() can savely be removed from under it. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Greg Ungerer <gerg@uclinux.org> CC: Richard Henderson <rth@twiddle.net> CC: Bryan Wu <bryan.wu@analog.com> CC: David Howells <dhowells@redhat.com> CC: Paul Mundt <lethal@linux-sh.org> CC: William Irwin <wli@holomorphy.com> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-12[SPARC]: Use shorter form of "get_zeroed_page".Robert P. J. Day
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: (24 commits) [SPARC]: Add solaris/sunos binary support to feature removal schedule. [SPARC]: Merge asm-sparc{,64}/a.out.h [SPARC]: Merge asm-sparc{,64}/fb.h [SPARC]: Merge asm-sparc{,64}/errno.h [SPARC]: Merge asm-sparc{,64}/emergency-restart.h [SPARC]: Merge asm-sparc{,64}/div64.h [SPARC]: Merge asm-sparc{,64}/device.h [SPARC]: Merge asm-sparc{,64}/current.h [SPARC]: Merge asm-sparc{,64}/cputime.h [SPARC]: Merge asm-sparc{,64}/cache.h [SPARC]: Merge asm-sparc{,64}/byteorder.h [SPARC]: Merge asm-sparc{,64}/bugs.h [SPARC]: Merge asm-sparc{,64}/bug.h [SPARC]: Kill BSD errno translation table and header files. [SPARC]: Merge asm-sparc{,64}/bpp.h [SPARC]: Merge include/asm-sparc{,64}/auxvec.h [SPARC]: Merge include/asm-sparc{,64}/of_device.h [SPARC]: Merge include/asm-sparc{,64}/prom.h [SPARC]: Remove of_platform_device_create [SPARC64]: Add kretprobe support. ...
2008-02-09[SPARC]: Merge asm-sparc{,64}/cache.hDavid S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-09[SPARC]: Kill BSD errno translation table and header files.David S. Miller
Completely unused. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-09[SPARC]: Remove of_platform_device_createStephen Rothwell
There are no callers of this on the Sparc platforms. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-09ide: introduce HAVE_IDESam Ravnborg
To allow flexible configuration of IDE introduce HAVE_IDE. All archs except arm, um and s390 unconditionally select it. For arm the actual configuration determine if IDE is supported. This is a step towards introducing drivers/Kconfig for arm. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Russell King - ARM Linux <linux@arm.linux.org.uk> Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-02-08CONFIG_HIGHPTE vs. sub-page page tables.Martin Schwidefsky
Background: I've implemented 1K/2K page tables for s390. These sub-page page tables are required to properly support the s390 virtualization instruction with KVM. The SIE instruction requires that the page tables have 256 page table entries (pte) followed by 256 page status table entries (pgste). The pgstes are only required if the process is using the SIE instruction. The pgstes are updated by the hardware and by the hypervisor for a number of reasons, one of them is dirty and reference bit tracking. To avoid wasting memory the standard pte table allocation should return 1K/2K (31/64 bit) and 2K/4K if the process is using SIE. Problem: Page size on s390 is 4K, page table size is 1K or 2K. That means the s390 version for pte_alloc_one cannot return a pointer to a struct page. Trouble is that with the CONFIG_HIGHPTE feature on x86 pte_alloc_one cannot return a pointer to a pte either, since that would require more than 32 bit for the return value of pte_alloc_one (and the pte * would not be accessible since its not kmapped). Solution: The only solution I found to this dilemma is a new typedef: a pgtable_t. For s390 pgtable_t will be a (pte *) - to be introduced with a later patch. For everybody else it will be a (struct page *). The additional problem with the initialization of the ptl lock and the NR_PAGETABLE accounting is solved with a constructor pgtable_page_ctor and a destructor pgtable_page_dtor. The page table allocation and free functions need to call these two whenever a page table page is allocated or freed. pmd_populate will get a pgtable_t instead of a struct page pointer. To get the pgtable_t back from a pmd entry that has been installed with pmd_populate a new function pmd_pgtable is added. It replaces the pmd_page call in free_pte_range and apply_to_pte_range. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08avoid overflows in kernel/time.cH. Peter Anvin
When the conversion factor between jiffies and milli- or microseconds is not a single multiply or divide, as for the case of HZ == 300, we currently do a multiply followed by a divide. The intervening result, however, is subject to overflows, especially since the fraction is not simplified (for HZ == 300, we multiply by 300 and divide by 1000). This is exposed to the user when passing a large timeout to poll(), for example. This patch replaces the multiply-divide with a reciprocal multiplication on 32-bit platforms. When the input is an unsigned long, there is no portable way to do this on 64-bit platforms there is no portable way to do this since it requires a 128-bit intermediate result (which gcc does support on 64-bit platforms but may generate libgcc calls, e.g. on 64-bit s390), but since the output is a 32-bit integer in the cases affected, just simplify the multiply-divide (*3/10 instead of *300/1000). The reciprocal multiply used can have off-by-one errors in the upper half of the valid output range. This could be avoided at the expense of having to deal with a potential 65-bit intermediate result. Since the intent is to avoid overflow problems and most of the other time conversions are only semiexact, the off-by-one errors were considered an acceptable tradeoff. At Ralf Baechle's suggestion, this version uses a Perl script to compute the necessary constants. We already have dependencies on Perl for kernel compiles. This does, however, require the Perl module Math::BigInt, which is included in the standard Perl distribution starting with version 5.8.0. In order to support older versions of Perl, include a table of canned constants in the script itself, and structure the script so that Math::BigInt isn't required if pulling values from said table. Running the script requires that the HZ value is available from the Makefile. Thus, this patch also adds the Kconfig variable CONFIG_HZ to the architectures which didn't already have it (alpha, cris, frv, h8300, m32r, m68k, m68knommu, sparc, v850, and xtensa.) It does *not* touch the sh or sh64 architectures, since Paul Mundt has dealt with those separately in the sh tree. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Ralf Baechle <ralf@linux-mips.org>, Cc: Sam Ravnborg <sam@ravnborg.org>, Cc: Paul Mundt <lethal@linux-sh.org>, Cc: Richard Henderson <rth@twiddle.net>, Cc: Michael Starvik <starvik@axis.com>, Cc: David Howells <dhowells@redhat.com>, Cc: Yoshinori Sato <ysato@users.sourceforge.jp>, Cc: Hirokazu Takata <takata@linux-m32r.org>, Cc: Geert Uytterhoeven <geert@linux-m68k.org>, Cc: Roman Zippel <zippel@linux-m68k.org>, Cc: William L. Irwin <sparclinux@vger.kernel.org>, Cc: Chris Zankel <chris@zankel.net>, Cc: H. Peter Anvin <hpa@zytor.com>, Cc: Jan Engelhardt <jengelh@computergmbh.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>