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* xtensa: fix compilation somewhatAlexey Dobriyan2009-03-10
| | | | | | | | | | | * ->put_char changes * HIGHMEM is bogus it seems, there is no kmap_atomic() et al * some includes Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Chris Zankel <zankel@tensilica.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* byteorder: make swab.h include asm/swab.h like a regular headerHarvey Harrison2009-01-14
| | | | | | | | | 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>
* xtensa: introduce swab.hHarvey Harrison2009-01-07
| | | | | | | Fixes compile breakage as linux/byteorder.h was removed. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/czankel/xtensa-2.6Linus Torvalds2009-01-07
|\ | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/czankel/xtensa-2.6: xtensa: Update platform files to reflect new location of the header files. xtensa: switch to packed struct unaligned access implementation xtensa: Add xt2000 support files. xtensa: move headers files to arch/xtensa/include xtensa: use the new byteorder headers
| * xtensa: Update platform files to reflect new location of the header files.Chris Zankel2008-12-04
| | | | | | | | | | | | | | | | Change 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18 moved the platform specific header files to arch/xtensa/platforms/<platform>/include/platform. These two file weren't updated. Signed-off-by: Chris Zankel <chris@zankel.net>
| * xtensa: switch to packed struct unaligned access implementationHarvey Harrison2008-11-11
| | | | | | | | | | | | | | Rely on byteorder.h checking for endianness. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Chris Zankel <chris@zankel.net>
| * xtensa: Add xt2000 support files.Chris Zankel2008-11-06
| | | | | | | | | | | | | | The last check-in to support the xt2000 development platform was missing some files. Signed-off-by: Chris Zankel <chris@zankel.net>
| * xtensa: move headers files to arch/xtensa/includeChris Zankel2008-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Move all header files for xtensa to arch/xtensa/include and platform and variant header files to the appropriate arch/xtensa/platforms/ and arch/xtensa/variants/ directories. Moving the files gets also rid of all uses of symlinks in the Makefile. This has been completed already for the majority of the architectures and xtensa is one out of six missing. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Chris Zankel <chris@zankel.net>
* | take init_fs to saner placeAl Viro2008-12-31
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | xtensa: Kill directly reference of netdev->privWang Chen2008-12-04
| | | | | | | | | | | | | | Simply replace netdev->priv with netdev_priv(). Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: convert more to %pMJohannes Berg2008-10-27
|/ | | | | | | | | A number of places still use %02x:...:%02x because it's in debug statements or for no real reason. Make a few of them use %pM. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/czankel/xtensa-2.6Linus Torvalds2008-10-23
|\ | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/czankel/xtensa-2.6: xtensa: Add config files for Diamond 232L - Rev B processor variant xtensa: Fix io regions xtensa: Add support for the Sonic Ethernet device for the XT2000 board. xtensa: replace remaining __FUNCTION__ occurrences xtensa: use newer __SPIN_LOCK_UNLOCKED macro XTENSA: warn about including <asm/rwsem.h> directly.
| * xtensa: Add config files for Diamond 232L - Rev B processor variantChris Zankel2008-10-21
| | | | | | | | | | | | | | The Diamond 232L processor is a pre-configured Xtensa processor tailored for Linux application. Signed-off-by: Chris Zankel <chris@zankel.net>
| * xtensa: replace remaining __FUNCTION__ occurrencesHarvey Harrison2008-10-14
| | | | | | | | | | | | | | | | __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris Zankel <chris@zankel.net>
| * xtensa: use newer __SPIN_LOCK_UNLOCKED macroRobert P. J. Day2008-10-14
| | | | | | | | | | | | | | | | SPIN_LOCK_UNLOCKED() breaks lockdep and is deprecated. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris Zankel <chris@zankel.net>
* | container freezer: implement freezer cgroup subsystemMatt Helsley2008-10-20
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements a new freezer subsystem in the control groups framework. It provides a way to stop and resume execution of all tasks in a cgroup by writing in the cgroup filesystem. The freezer subsystem in the container filesystem defines a file named freezer.state. Writing "FROZEN" to the state file will freeze all tasks in the cgroup. Subsequently writing "RUNNING" will unfreeze the tasks in the cgroup. Reading will return the current state. * Examples of usage : # mkdir /containers/freezer # mount -t cgroup -ofreezer freezer /containers # mkdir /containers/0 # echo $some_pid > /containers/0/tasks to get status of the freezer subsystem : # cat /containers/0/freezer.state RUNNING to freeze all tasks in the container : # echo FROZEN > /containers/0/freezer.state # cat /containers/0/freezer.state FREEZING # cat /containers/0/freezer.state FROZEN to unfreeze all tasks in the container : # echo RUNNING > /containers/0/freezer.state # cat /containers/0/freezer.state RUNNING This is the basic mechanism which should do the right thing for user space task in a simple scenario. It's important to note that freezing can be incomplete. In that case we return EBUSY. This means that some tasks in the cgroup are busy doing something that prevents us from completely freezing the cgroup at this time. After EBUSY, the cgroup will remain partially frozen -- reflected by freezer.state reporting "FREEZING" when read. The state will remain "FREEZING" until one of these things happens: 1) Userspace cancels the freezing operation by writing "RUNNING" to the freezer.state file 2) Userspace retries the freezing operation by writing "FROZEN" to the freezer.state file (writing "FREEZING" is not legal and returns EIO) 3) The tasks that blocked the cgroup from entering the "FROZEN" state disappear from the cgroup's set of tasks. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: export thaw_process] Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Matt Helsley <matthltc@us.ibm.com> Acked-by: Serge E. Hallyn <serue@us.ibm.com> Tested-by: Matt Helsley <matthltc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* xtensa: remove dead CONFIG_BLK_DEV_IDE codeAdrian Bunk2008-10-13
| | | | | | | | I don't know why this was there, but it was dead code. Signed-off-by: Adrian Bunk <bunk@kernel.org> Cc: chris@zankel.net Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* remove unneeded #include <linux/ide.h>'sAdrian Bunk2008-08-05
| | | | | | | | | | | This patch remove unneeded #include <linux/ide.h>'s. It also adds a required #include <linux/interrupt.h> that was previously implicitely pulled by ide.h Signed-off-by: Adrian Bunk <bunk@kernel.org> [bart: revert change to tests/lkdtm.c (spotted by Stephen Rothwell)] Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* xtensa: use generic show_mem()Johannes Weiner2008-07-26
| | | | | | | | | | | | | | | | | Remove arch-specific show_mem() in favor of the generic version. This also removes the following redundant information display: - free pages, printed by show_free_areas() - pages in swapcache, printed by show_swap_cache_info() where show_mem() calls show_free_areas(), which calls show_swap_cache_info(). Signed-off-by: Johannes Weiner <hannes@saeurebad.de> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SL*B: drop kmem cache argument from constructorAlexey Dobriyan2008-07-26
| | | | | | | | | | | | | | | | | | | | | | | | Kmem cache passed to constructor is only needed for constructors that are themselves multiplexeres. Nobody uses this "feature", nor does anybody uses passed kmem cache in non-trivial way, so pass only pointer to object. Non-trivial places are: arch/powerpc/mm/init_64.c arch/powerpc/mm/hugetlbpage.c This is flag day, yes. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Christoph Lameter <cl@linux-foundation.org> Cc: Jon Tollefson <kniht@linux.vnet.ibm.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Matt Mackall <mpm@selenic.com> [akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c] [akpm@linux-foundation.org: fix mm/slab.c] [akpm@linux-foundation.org: fix ubifs] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* flag parameters: pipeUlrich Drepper2008-07-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces the new syscall pipe2 which is like pipe but it also takes an additional parameter which takes a flag value. This patch implements the handling of O_CLOEXEC for the flag. I did not add support for the new syscall for the architectures which have a special sys_pipe implementation. I think the maintainers of those archs have the chance to go with the unified implementation but that's up to them. The implementation introduces do_pipe_flags. I did that instead of changing all callers of do_pipe because some of the callers are written in assembler. I would probably screw up changing the assembly code. To avoid breaking code do_pipe is now a small wrapper around do_pipe_flags. Once all callers are changed over to do_pipe_flags the old do_pipe function can be removed. The following test must be adjusted for architectures other than x86 and x86-64 and in case the syscall numbers changed. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #include <fcntl.h> #include <stdio.h> #include <unistd.h> #include <sys/syscall.h> #ifndef __NR_pipe2 # ifdef __x86_64__ # define __NR_pipe2 293 # elif defined __i386__ # define __NR_pipe2 331 # else # error "need __NR_pipe2" # endif #endif int main (void) { int fd[2]; if (syscall (__NR_pipe2, fd, 0) != 0) { puts ("pipe2(0) failed"); return 1; } for (int i = 0; i < 2; ++i) { int coe = fcntl (fd[i], F_GETFD); if (coe == -1) { puts ("fcntl failed"); return 1; } if (coe & FD_CLOEXEC) { printf ("pipe2(0) set close-on-exit for fd[%d]\n", i); return 1; } } close (fd[0]); close (fd[1]); if (syscall (__NR_pipe2, fd, O_CLOEXEC) != 0) { puts ("pipe2(O_CLOEXEC) failed"); return 1; } for (int i = 0; i < 2; ++i) { int coe = fcntl (fd[i], F_GETFD); if (coe == -1) { puts ("fcntl failed"); return 1; } if ((coe & FD_CLOEXEC) == 0) { printf ("pipe2(O_CLOEXEC) does not set close-on-exit for fd[%d]\n", i); return 1; } } close (fd[0]); close (fd[1]); puts ("OK"); return 0; } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Ulrich Drepper <drepper@redhat.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Cc: Michael Kerrisk <mtk.manpages@googlemail.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>
* PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architecturesAndrea Righi2008-07-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit boundary. For example: u64 val = PAGE_ALIGN(size); always returns a value < 4GB even if size is greater than 4GB. The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for example): #define PAGE_SHIFT 12 #define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE-1)) ... #define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK) The "~" is performed on a 32-bit value, so everything in "and" with PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary. Using the ALIGN() macro seems to be the right way, because it uses typeof(addr) for the mask. Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in include/linux/mm.h. See also lkml discussion: http://lkml.org/lkml/2008/6/11/237 [akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c] [akpm@linux-foundation.org: fix v850] [akpm@linux-foundation.org: fix powerpc] [akpm@linux-foundation.org: fix arm] [akpm@linux-foundation.org: fix mips] [akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c] [akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c] [akpm@linux-foundation.org: fix powerpc] Signed-off-by: Andrea Righi <righi.andrea@gmail.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>
* remove mention of CONFIG_KMOD from documentationJohannes Berg2008-07-22
| | | | | | | | | | Also includes a few Kconfig files (xtensa, blackfin) Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: linux-doc@vger.kernel.org Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Randy Dunlap <rdunlap@xenotime.net>
* [PATCH] take init_files to fs/file.cAl Viro2008-05-16
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* xtensa: use kbuild.h macros instead of defining them in asm-offsets.cChristoph Lameter2008-04-29
| | | | | | | Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Generic semaphore implementationMatthew Wilcox2008-04-17
| | | | | | | | | | | 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>
* [XTENSA] Allow debugger to modify the WINDOWBASE register.Chris Zankel2008-02-13
| | | | | | | | | | | For the 'return' command, GDB needs to adjust WINDOWBASE. In case WB is different from 0, we need to rotate the window register file and update WINDOWSTART and WMASK. This patch also removes some ret|= statements for __get_user/__put_user as the address range was alrady checked a couple of lines earlier. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Fix makefile to work with binutils-2.18.Bob Wilson2008-02-13
| | | | | | | | | | When building with binutils-2.18, vmlinux includes .note.gnu.build-id sections that need to be stripped out when building the binary image. The old .xt.insn sections haven't been used for a long time, so don't bother stripping them. Signed-off-by: Bob Wilson <bob.wilson@acm.org> Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Fix register corruption for certain processor configurationsChris Zankel2008-02-13
| | | | | | | | | | For processor configurations that have optional registers (compiler-used but non-coprocessor), user space registers might get corrupted when there are only 4 registers in the current window-frame, ie. register a4 belongs to the oldest frame in the register file. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Add support for the sa_restorer functionChris Zankel2008-02-13
| | | | | | | | | | Supporting the sa_restorer function allows for better security since the sigreturn system call doesn't need to be placed on the stack, so the stack doesn't need to be executable. This requires support from the c-library as it has to provide the restorer function. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Add support for configurable registers and coprocessorsChris Zankel2008-02-13
| | | | | | | | | | | | | | | | | | | | The Xtensa architecture allows to define custom instructions and registers. Registers that are bound to a coprocessor are only accessible if the corresponding enable bit is set, which allows to implement a 'lazy' context switch mechanism. Other registers needs to be saved and restore at the time of the context switch or during interrupt handling. This patch adds support for these additional states: - save and restore registers that are used by the compiler upon interrupt entry and exit. - context switch additional registers unbound to any coprocessor - 'lazy' context switch of registers bound to a coprocessor - ptrace interface to provide access to additional registers - update configuration files in include/asm-xtensa/variant-fsf Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Use preprocessor to generate the linker script for the ELF boot imageChris Zankel2008-02-13
| | | | | Signed-off-by: Marc Gauthier <marc@tensilica.com> Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Add missing RELOCATE_ENTRY for debug vectorMarc Gauthier2008-02-13
| | | | | | We also need to relocate the debug vector if in RAM. Signed-off-by: Marc Gauthier <marc@tensilica.com>
* [XTENSA] Remove unused codeChris Zankel2008-02-13
| | | | | | | | We will never (need to) support signal handling coming from a double exception. There are too many things that could go wrong and delivering signals is not the fastest method for IPC, anyway. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Fix modules for non-exec processor configurationsChris Zankel2008-02-13
| | | | | | | | We need to use vmalloc_exec for module loading. Also remove the definitions MODULE_START and MODULE_END, which wasn't used, and increase the VMALLOC memory range accordingly. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Fix comments regarding the number of frames to saveChris Zankel2008-02-13
| | | | | Signed-off-by: Marc Gauthier <marc@tensilica.com> Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Add missing a2 register restore in register spill routineChris Zankel2008-02-13
| | | | | | | | | Register a2 is saved in depc but wasn't getting restored before returning from _spill_registers when there weren't any registers to spill. The mask to cut the top bit from the rotated WINDOWMASK register was also one bit short. Signed-off-by: CHris Zankel <chris@zankel.net>
* [XTENSA] adjust boot linker script start addressesMarc Gauthier2008-02-13
| | | | | | | | | | Move boot-redboot load address from 0xD0200000 to 0xD1000000 to make space for larger kernel images, in particular those with an embedded initramfs filesystem. Also properly set the ELF start address in boot-elf images so that PC need not be set manually when loading them using GDB. Signed-off-by: Marc Gauthier <marc@tensilica.com>
* [XTENSA] Remove oldmask from sigcontext and fix register flushChris Zankel2008-02-13
| | | | | | | Remove oldmask from the sigcontext structure. Also update wmask and windowstart when we flush the AR registers to stack. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Clean up elf-gregset.Chris Zankel2008-02-13
| | | | | | | | | | | Remove additional registers from the ELF gregset structure that are only used by the kernel or are not required or invalid in user-space. The ar registers are always aligned to a windowbase value of 0, and the WB register is always assumed to be 0. Increase the size of the structure to 128 entries. This will provide enough space in future. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Fix icache flush for cache aliasingChris Zankel2008-02-13
| | | | | | | Set the execution bit in the temporary TLB when we flush the instruction cache. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Prevent inlining ISS platform asm constructsMarc Gauthier2008-02-13
| | | | | | | | The simcall asm macro assumes Windowed ABI parameter passing in registers, and doesn't work if its containing function gets inlined. This fix prevents that from happening. Signed-off-by: Marc Gauthier <marc@tensilica.com>
* [XTENSA] Flush the page-address in update-mmu instead of user-addressChris Zankel2008-02-13
| | | | | | | | The TLB entry for the user address doesn't exist at the time we want to flush the caches, so use the page address. Note that processor configurations with cache-aliasing issues are treated separately. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Fix argument list for pgd_ctor constructor.Chris Zankel2008-02-13
| | | | | | | The argument list for ctor function element in the kmem_cache structure has changed. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Concentrate platforms into one platforms directory.Chris Zankel2008-02-13
| | | | | | | | Create arch/xtensa/platforms/ directory to concentrate all platforms under that subdirectory and moves the ISS platform to that directory. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Add .literal sections for various init sectiont to linker scriptChris Zankel2008-02-13
| | | | | | | | | Xtensa requires separate .literal section for each .text section. Adding addition init sections for cpuinit, meminit, and devinit, broke the Xtensa linker script, so, add these literal sections manually for now. Signed-off-by: Chris Zankel <chris@zankel.net>
* [XTENSA] Remove dead code reported by Robert P. J. Day.Adrian Bunk2008-02-13
| | | | | | Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Christian Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* [XTENSA] Remove duplicate includes.Chris Zankel2008-02-13
| | | | | | Signed-off-by: Lucas Woods <woodzy@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Christian Zankel <chris@zankel.net>
* ide: introduce HAVE_IDESam Ravnborg2008-02-09
| | | | | | | | | | | | 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>
* avoid overflows in kernel/time.cH. Peter Anvin2008-02-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
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