linux-toradex.git/kernel/resource.c, branch imx-android-r10.4 Linux kernel for Apalis and Colibri modules resource: shared I/O region support 2010-05-11T19:01:10+00:00 Alan Cox alan@linux.intel.com 2010-03-29T17:38:00+00:00 8b6d043b7ee2d1b819dc833d677ea2aead71a0c0 SuperIO devices share regions and use lock/unlock operations to chip select. We therefore need to be able to request a resource and wait for it to be freed by whichever other SuperIO device currently hogs it. Right now you have to poll which is horrible. Add a MUXED field to IO port resources. If the MUXED field is set on the resource and on the request (via request_muxed_region) then we block until the previous owner of the muxed resource releases their region. This allows us to implement proper resource sharing and locking for superio chips using code of the form enable_my_superio_dev() { request_muxed_region(0x44, 0x02, "superio:watchdog"); outb() ..sequence to enable chip } disable_my_superio_dev() { outb() .. sequence of disable chip release_region(0x44, 0x02); } Signed-off-by: Giel van Schijndel <me@mortis.eu> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> 
SuperIO devices share regions and use lock/unlock operations to chip
select.  We therefore need to be able to request a resource and wait for
it to be freed by whichever other SuperIO device currently hogs it.
Right now you have to poll which is horrible.

Add a MUXED field to IO port resources. If the MUXED field is set on the
resource and on the request (via request_muxed_region) then we block
until the previous owner of the muxed resource releases their region.

This allows us to implement proper resource sharing and locking for
superio chips using code of the form

enable_my_superio_dev() {
	request_muxed_region(0x44, 0x02, "superio:watchdog");
	outb() ..sequence to enable chip
}

disable_my_superio_dev() {
	outb() .. sequence of disable chip
	release_region(0x44, 0x02);
}

Signed-off-by: Giel van Schijndel <me@mortis.eu>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
resources: add interfaces that return conflict information 2010-03-23T20:33:50+00:00 Bjorn Helgaas bjorn.helgaas@hp.com 2010-03-12T00:01:09+00:00 66f1207bce10fd80ee8ce99b67d617644612f05e request_resource() and insert_resource() only return success or failure, which no information about what existing resource conflicted with the proposed new reservation. This patch adds request_resource_conflict() and insert_resource_conflict(), which return the conflicting resource. Callers may use this for better error messages or to adjust the new resource and retry the request. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> 
request_resource() and insert_resource() only return success or failure,
which no information about what existing resource conflicted with the
proposed new reservation.  This patch adds request_resource_conflict()
and insert_resource_conflict(), which return the conflicting resource.

Callers may use this for better error messages or to adjust the new
resource and retry the request.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-03-03T17:11:02+00:00 Linus Torvalds torvalds@linux-foundation.org 2010-03-03T17:11:02+00:00 2a32f2db132264c356aea30a8270d3e68d96c509 * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: resource: Fix broken indentation resource: Fix generic page_is_ram() for partial RAM pages x86, paravirt: Remove kmap_atomic_pte paravirt op. x86, vmi: Disable highmem PTE allocation even when CONFIG_HIGHPTE=y x86, xen: Disable highmem PTE allocation even when CONFIG_HIGHPTE=y 
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  resource: Fix broken indentation
  resource: Fix generic page_is_ram() for partial RAM pages
  x86, paravirt: Remove kmap_atomic_pte paravirt op.
  x86, vmi: Disable highmem PTE allocation even when CONFIG_HIGHPTE=y
  x86, xen: Disable highmem PTE allocation even when CONFIG_HIGHPTE=y
resource: Fix broken indentation 2010-03-02T19:21:09+00:00 H. Peter Anvin hpa@zytor.com 2010-03-02T19:21:09+00:00 f41496607e03ab99f263b8e26689ad0fc853007f Fix broken indentation in patch 37b99dd5372cff42f83210c280f314f10f99138e. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Wu Fengguang <fengguang.wu@intel.com> LKML-Reference: <20100301135551.GA9998@localhost> Signed-off-by: H. Peter Anvin <hpa@zytor.com> 
Fix broken indentation in patch
37b99dd5372cff42f83210c280f314f10f99138e.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
LKML-Reference: <20100301135551.GA9998@localhost>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
resource: Fix generic page_is_ram() for partial RAM pages 2010-03-01T18:18:32+00:00 Wu Fengguang fengguang.wu@intel.com 2010-03-01T13:55:51+00:00 37b99dd5372cff42f83210c280f314f10f99138e The System RAM walk shall skip partial RAM pages and avoid calling func() on them. So that page_is_ram() return 0 for a partial RAM page. In particular, it shall not call func() with len=0. This fixes a boot time bug reported by Sachin and root caused by Thomas: > >>> WARNING: at arch/x86/mm/ioremap.c:111 __ioremap_caller+0x169/0x2f1() > >>> Hardware name: BladeCenter LS21 -[79716AA]- > >>> Modules linked in: > >>> Pid: 0, comm: swapper Not tainted 2.6.33-git6-autotest #1 > >>> Call Trace: > >>> [<ffffffff81047cff>] ? __ioremap_caller+0x169/0x2f1 > >>> [<ffffffff81063b7d>] warn_slowpath_common+0x77/0xa4 > >>> [<ffffffff81063bb9>] warn_slowpath_null+0xf/0x11 > >>> [<ffffffff81047cff>] __ioremap_caller+0x169/0x2f1 > >>> [<ffffffff813747a3>] ? acpi_os_map_memory+0x12/0x1b > >>> [<ffffffff81047f10>] ioremap_nocache+0x12/0x14 > >>> [<ffffffff813747a3>] acpi_os_map_memory+0x12/0x1b > >>> [<ffffffff81282fa0>] acpi_tb_verify_table+0x29/0x5b > >>> [<ffffffff812827f0>] acpi_load_tables+0x39/0x15a > >>> [<ffffffff8191c8f8>] acpi_early_init+0x60/0xf5 > >>> [<ffffffff818f2cad>] start_kernel+0x397/0x3a7 > >>> [<ffffffff818f2295>] x86_64_start_reservations+0xa5/0xa9 > >>> [<ffffffff818f237a>] x86_64_start_kernel+0xe1/0xe8 > >>> ---[ end trace 4eaa2a86a8e2da22 ]--- > >>> ioremap reserve_memtype failed -22 The return code is -EINVAL, so it failed in the is_ram check, which is not too surprising > BIOS-provided physical RAM map: > BIOS-e820: 0000000000000000 - 000000000009c000 (usable) > BIOS-e820: 000000000009c000 - 00000000000a0000 (reserved) > BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) > BIOS-e820: 0000000000100000 - 00000000cffa3900 (usable) > BIOS-e820: 00000000cffa3900 - 00000000cffa7400 (ACPI data) The ACPI data is not starting on a page boundary and neither does the usable RAM area end on a page boundary. Very useful ! > ACPI: DSDT 00000000cffa3900 036CE (v01 IBM SERLEWIS 00001000 INTL 20060912) ACPI is trying to map DSDT at cffa3900, which results in a check vs. cffa3000 which is the relevant page boundary. The generic is_ram check correctly identifies that as RAM because it's in the usable resource area. The old e820 based is_ram check does not take overlapping resource areas into account. That's why it works. CC: Sachin Sant <sachinp@in.ibm.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> LKML-Reference: <20100301135551.GA9998@localhost> Signed-off-by: H. Peter Anvin <hpa@zytor.com> 
The System RAM walk shall skip partial RAM pages and avoid calling
func() on them. So that page_is_ram() return 0 for a partial RAM page.

In particular, it shall not call func() with len=0.
This fixes a boot time bug reported by Sachin and root caused by Thomas:

> >>> WARNING: at arch/x86/mm/ioremap.c:111 __ioremap_caller+0x169/0x2f1()
> >>> Hardware name: BladeCenter LS21 -[79716AA]-
> >>> Modules linked in:
> >>> Pid: 0, comm: swapper Not tainted 2.6.33-git6-autotest #1
> >>> Call Trace:
> >>> [<ffffffff81047cff>] ? __ioremap_caller+0x169/0x2f1
> >>> [<ffffffff81063b7d>] warn_slowpath_common+0x77/0xa4
> >>> [<ffffffff81063bb9>] warn_slowpath_null+0xf/0x11
> >>> [<ffffffff81047cff>] __ioremap_caller+0x169/0x2f1
> >>> [<ffffffff813747a3>] ? acpi_os_map_memory+0x12/0x1b
> >>> [<ffffffff81047f10>] ioremap_nocache+0x12/0x14
> >>> [<ffffffff813747a3>] acpi_os_map_memory+0x12/0x1b
> >>> [<ffffffff81282fa0>] acpi_tb_verify_table+0x29/0x5b
> >>> [<ffffffff812827f0>] acpi_load_tables+0x39/0x15a
> >>> [<ffffffff8191c8f8>] acpi_early_init+0x60/0xf5
> >>> [<ffffffff818f2cad>] start_kernel+0x397/0x3a7
> >>> [<ffffffff818f2295>] x86_64_start_reservations+0xa5/0xa9
> >>> [<ffffffff818f237a>] x86_64_start_kernel+0xe1/0xe8
> >>> ---[ end trace 4eaa2a86a8e2da22 ]---
> >>> ioremap reserve_memtype failed -22

The return code is -EINVAL, so it failed in the is_ram check, which is
not too surprising

> BIOS-provided physical RAM map:
>  BIOS-e820: 0000000000000000 - 000000000009c000 (usable)
>  BIOS-e820: 000000000009c000 - 00000000000a0000 (reserved)
>  BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
>  BIOS-e820: 0000000000100000 - 00000000cffa3900 (usable)
>  BIOS-e820: 00000000cffa3900 - 00000000cffa7400 (ACPI data)

The ACPI data is not starting on a page boundary and neither does the
usable RAM area end on a page boundary. Very useful !

> ACPI: DSDT 00000000cffa3900 036CE (v01 IBM    SERLEWIS 00001000 INTL 20060912)

ACPI is trying to map DSDT at cffa3900, which results in a check
vs. cffa3000 which is the relevant page boundary. The generic is_ram
check correctly identifies that as RAM because it's in the usable
resource area. The old e820 based is_ram check does not take
overlapping resource areas into account. That's why it works.

CC: Sachin Sant <sachinp@in.ibm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
LKML-Reference: <20100301135551.GA9998@localhost>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-28T18:38:45+00:00 Linus Torvalds torvalds@linux-foundation.org 2010-02-28T18:38:45+00:00 46bbffad54bd48bb809f2691c1970a79a588976b * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, mm: Unify kernel_physical_mapping_init() API x86, mm: Allow highmem user page tables to be disabled at boot time x86: Do not reserve brk for DMI if it's not going to be used x86: Convert tlbstate_lock to raw_spinlock x86: Use the generic page_is_ram() x86: Remove BIOS data range from e820 Move page_is_ram() declaration to mm.h Generic page_is_ram: use __weak resources: introduce generic page_is_ram() 
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, mm: Unify kernel_physical_mapping_init() API
  x86, mm: Allow highmem user page tables to be disabled at boot time
  x86: Do not reserve brk for DMI if it's not going to be used
  x86: Convert tlbstate_lock to raw_spinlock
  x86: Use the generic page_is_ram()
  x86: Remove BIOS data range from e820
  Move page_is_ram() declaration to mm.h
  Generic page_is_ram: use __weak
  resources: introduce generic page_is_ram()
resource: add release_child_resources 2010-02-23T00:17:00+00:00 Yinghai Lu yinghai@kernel.org 2009-12-22T23:02:22+00:00 5eeec0ec931a01e85b3701ce121b7d8a1800ec60 Useful for freeing a portion of the resource tree, e.g. when trying to reallocate resources more efficiently. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> 
Useful for freeing a portion of the resource tree, e.g. when trying to
reallocate resources more efficiently.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
resource/PCI: mark struct resource as const 2010-02-23T00:16:57+00:00 Dominik Brodowski linux@dominikbrodowski.net 2010-01-01T16:40:50+00:00 3b7a17fcdae532d29dffab9d564a28be08960988 Now that we return the new resource start position, there is no need to update "struct resource" inside the align function. Therefore, mark the struct resource as const. Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> 
Now that we return the new resource start position, there is no
need to update "struct resource" inside the align function.
Therefore, mark the struct resource as const.

Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
resource/PCI: align functions now return start of resource 2010-02-23T00:16:56+00:00 Dominik Brodowski linux@dominikbrodowski.net 2010-01-01T16:40:49+00:00 b26b2d494b659f988b4d75eb394dfa0ddac415c9 As suggested by Linus, align functions should return the start of a resource, not void. An update of "res->start" is no longer necessary. Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> 
As suggested by Linus, align functions should return the start
of a resource, not void. An update of "res->start" is no longer
necessary.

Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Merge branch 'linus' into x86/mm 2010-02-17T17:28:05+00:00 Thomas Gleixner tglx@linutronix.de 2010-02-17T17:27:37+00:00 b7e56edba4b02f2079042c326a8cd72a44635817 x86/mm is on 32-rc4 and missing the spinlock namespace changes which are needed for further commits into this topic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 
x86/mm is on 32-rc4 and missing the spinlock namespace changes which
are needed for further commits into this topic.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>