linux-toradex.git/kernel/resource.c, branch tegra-10.9.9

walk system ram range

2009-09-23T14:39:41+00:00

Originally, walk_memory_resource() was introduced to traverse all memory
of "System RAM" for detecting memory hotplug/unplug range.  For doing so,
flags of IORESOUCE_MEM|IORESOURCE_BUSY was used and this was enough for
memory hotplug.

But for using other purpose, /proc/kcore, this may includes some firmware
area marked as IORESOURCE_BUSY | IORESOUCE_MEM.  This patch makes the
check strict to find out busy "System RAM".

Note: PPC64 keeps their own walk_memory_resouce(), which walk through
ppc64's lmb informaton.  Because old kclist_add() is called per lmb, this
patch makes no difference in behavior, finally.

And this patch removes CONFIG_MEMORY_HOTPLUG check from this function.
Because pfn_valid() just show "there is memmap or not* and cannot be used
for "there is physical memory or not", this function is useful in generic
to scan physical memory range.

Signed-off-by: KAMEZAWA Hiroyuki 
Cc: Ralf Baechle 
Cc: Benjamin Herrenschmidt 
Cc: WANG Cong 
Cc: Américo Wang 
Cc: David Rientjes 
Cc: Roland Dreier 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kernel/resource.c: fix sign extension in reserve_setup()

2009-07-01T01:56:00+00:00

When the 32-bit signed quantities get assigned to the u64 resource_size_t,
they are incorrectly sign-extended.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13253
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=9905

Signed-off-by: Zhang Rui 
Reported-by: Leann Ogasawara 
Cc: Pierre Ossman 
Reported-by: 
Tested-by: 
Cc: 
Cc: Jesse Barnes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Remove 'recurse into child resources' logic from 'reserve_region_with_split()'

2009-04-19T04:44:24+00:00

This function is not actually used right now, since the original use
case for it was done with insert_resource_expand_to_fit() instead.

However, we now have another usage case that wants to basically do a
"reserve IO resource, splitting around existing resources", however that
one doesn't actually want the "recurse into the conflicting resource"
logic at all.

And since recursing into the conflicting resource was the most complex
part, and isn't wanted, just remove it.  Maybe we'll some day want both
versions, but we can just resurrect the logic then.

Tested-by: Yinghai Lu 
Signed-off-by: Linus Torvalds

resources: fix parameter name and kernel-doc

2009-01-16T00:39:38+00:00

Fix __request_region() parameter kernel-doc notation and parameter name:

Warning(linux-2.6.28-git10//kernel/resource.c:627): No description found for parameter 'flags'

Signed-off-by: Randy Dunlap 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

resource: allow MMIO exclusivity for device drivers

2009-01-07T19:12:32+00:00

Device drivers that use pci_request_regions() (and similar APIs) have a
reasonable expectation that they are the only ones accessing their device.
As part of the e1000e hunt, we were afraid that some userland (X or some
bootsplash stuff) was mapping the MMIO region that the driver thought it
had exclusively via /dev/mem or via various sysfs resource mappings.

This patch adds the option for device drivers to cause their reserved
regions to the "banned from /dev/mem use" list, so now both kernel memory
and device-exclusive MMIO regions are banned.
NOTE: This is only active when CONFIG_STRICT_DEVMEM is set.

In addition to the config option, a kernel parameter iomem=relaxed is
provided for the cases where developers want to diagnose, in the field,
drivers issues from userspace.

Reviewed-by: Matthew Wilcox 
Signed-off-by: Arjan van de Ven 
Signed-off-by: Jesse Barnes

resources: skip sanity check of busy resources

2008-12-16T22:30:49+00:00

Impact: reduce false positives in iomem_map_sanity_check()

Some drivers (vesafb) only map/reserve a portion of a resource.
If then some other driver comes in and maps the whole resource,
the current code WARN_ON's. This is not the intent of the checks
in iomem_map_sanity_check(); rather these checks want to
warn when crossing *hardware* resources only.

This patch skips BUSY resources as suggested by Linus.

Note: having two drivers talk to the same hardware at the same
time is obviously not optimal behavior, but that's a separate story.

Signed-off-by: Arjan van de Ven 
Signed-off-by: Ingo Molnar

reserve_region_with_split: Fix GFP_KERNEL usage under spinlock

2008-11-01T16:53:58+00:00

This one apparently doesn't generate any warnings, because the function
is only used during system bootup, when the warnings are disabled.  But
it's still very wrong.

The __reserve_region_with_split() function is called with the
resource_lock held for writing, so it must only ever do GFP_ATOMIC
allocations.

Signed-off-by: Linus Torvalds

resources: fix x86info results ioremap.c:226 __ioremap_caller+0xf2/0x2d6() WARNINGs

2008-10-28T18:56:17+00:00

Impact: avoid false-positive WARN_ON()

Andi Kleen reported:
> When running x86info on a 2.6.27-git8 system I get
>
> resource map sanity check conflict: 0x9e000 0x9efff 0x10000 0x9e7ff System RAM
> ------------[ cut here ]------------
> WARNING: at /home/lsrc/linux/arch/x86/mm/ioremap.c:226 __ioremap_caller+0xf2/0x2d6()
> ...

Some of the pages below the 1MB ISA addresses will be shared typically by both
BIOS and system usable RAM. For example:
	BIOS-e820: 0000000000000000 - 000000000009f800 (usable)
	BIOS-e820: 000000000009f800 - 00000000000a0000 (reserved)

x86info reads the low physical address using /dev/mem, which internally
uses ioremap() for accessing non RAM pages. ioremap() of such low
pages conflicts with multiple resource entities leading to the
above warning.

Change the iomem_map_sanity_check() to allow mapping a page spanning multiple
resource entities (minimum granularity that one can map is a page anyhow).

Signed-off-by: Suresh Siddha 
Signed-off-by: Ingo Molnar

kernel/resource: fix reserve_region_with_split() section mismatch

2008-10-23T19:54:34+00:00

Impact: cleanup, small kernel text size reduction, no functionality changed

reserve_region_with_split() calls in to __reserve_region_with_split(),
which is an __init function. The only caller of reserve_region_with_split()
is an __init function, so make it __init too.

Signed-off-by: Paul Mundt 
Signed-off-by: Ingo Molnar

Merge branch 'core-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2008-10-16T22:17:40+00:00

* 'core-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  do_generic_file_read: s/EINTR/EIO/ if lock_page_killable() fails
  softirq, warning fix: correct a format to avoid a warning
  softirqs, debug: preemption check
  x86, pci-hotplug, calgary / rio: fix EBDA ioremap()
  IO resources, x86: ioremap sanity check to catch mapping requests exceeding, fix
  IO resources, x86: ioremap sanity check to catch mapping requests exceeding the BAR sizes
  softlockup: Documentation/sysctl/kernel.txt: fix softlockup_thresh description
  dmi scan: warn about too early calls to dmi_check_system()
  generic: redefine resource_size_t as phys_addr_t
  generic: make PFN_PHYS explicitly return phys_addr_t
  generic: add phys_addr_t for holding physical addresses
  softirq: allocate less vectors
  IO resources: fix/remove printk
  printk: robustify printk, update comment
  printk: robustify printk, fix #2
  printk: robustify printk, fix
  printk: robustify printk

Fixed up conflicts in:
	arch/powerpc/include/asm/types.h
	arch/powerpc/platforms/Kconfig.cputype
manually.