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2015-02-19x86/mm/pat: Ensure different messages in STRICT_DEVMEM and PAT casesPavel Machek
STRICT_DEVMEM and PAT produce same failure accessing /dev/mem, which is quite confusing to the user. Make printk messages different to lessen confusion. Signed-off-by: Pavel Machek <pavel@ucw.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-20x86: Don't rely on VMWare emulating PAT MSR correctlyJuergen Gross
VMWare seems not to emulate the PAT MSR correctly: reaeding MSR_IA32_CR_PAT returns 0 even after writing another value to it. Commit bd809af16e3ab triggers this VMWare bug when the kernel is booted as a VMWare guest. Detect this bug and don't use the read value if it is 0. Fixes: bd809af16e3ab "x86: Enable PAT to use cache mode translation tables" Reported-and-tested-by: Jongman Heo <jongman.heo@samsung.com> Acked-by: Alok N Kataria <akataria@vmware.com> Signed-off-by: Juergen Gross <jgross@suse.com> Link: http://lkml.kernel.org/r/1421039745-14335-1-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-10Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm tree changes from Ingo Molnar: "The biggest change is full PAT support from Jürgen Gross: The x86 architecture offers via the PAT (Page Attribute Table) a way to specify different caching modes in page table entries. The PAT MSR contains 8 entries each specifying one of 6 possible cache modes. A pte references one of those entries via 3 bits: _PAGE_PAT, _PAGE_PWT and _PAGE_PCD. The Linux kernel currently supports only 4 different cache modes. The PAT MSR is set up in a way that the setting of _PAGE_PAT in a pte doesn't matter: the top 4 entries in the PAT MSR are the same as the 4 lower entries. This results in the kernel not supporting e.g. write-through mode. Especially this cache mode would speed up drivers of video cards which now have to use uncached accesses. OTOH some old processors (Pentium) don't support PAT correctly and the Xen hypervisor has been using a different PAT MSR configuration for some time now and can't change that as this setting is part of the ABI. This patch set abstracts the cache mode from the pte and introduces tables to translate between cache mode and pte bits (the default cache mode "write back" is hard-wired to PAT entry 0). The tables are statically initialized with values being compatible to old processors and current usage. As soon as the PAT MSR is changed (or - in case of Xen - is read at boot time) the tables are changed accordingly. Requests of mappings with special cache modes are always possible now, in case they are not supported there will be a fallback to a compatible but slower mode. Summing it up, this patch set adds the following features: - capability to support WT and WP cache modes on processors with full PAT support - processors with no or uncorrect PAT support are still working as today, even if WT or WP cache mode are selected by drivers for some pages - reduction of Xen special handling regarding cache mode Another change is a boot speedup on ridiculously large RAM systems, plus other smaller fixes" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86: mm: Move PAT only functions to mm/pat.c xen: Support Xen pv-domains using PAT x86: Enable PAT to use cache mode translation tables x86: Respect PAT bit when copying pte values between large and normal pages x86: Support PAT bit in pagetable dump for lower levels x86: Clean up pgtable_types.h x86: Use new cache mode type in memtype related functions x86: Use new cache mode type in mm/ioremap.c x86: Use new cache mode type in setting page attributes x86: Remove looking for setting of _PAGE_PAT_LARGE in pageattr.c x86: Use new cache mode type in track_pfn_remap() and track_pfn_insert() x86: Use new cache mode type in mm/iomap_32.c x86: Use new cache mode type in asm/pgtable.h x86: Use new cache mode type in arch/x86/mm/init_64.c x86: Use new cache mode type in arch/x86/pci x86: Use new cache mode type in drivers/video/fbdev/vermilion x86: Use new cache mode type in drivers/video/fbdev/gbefb.c x86: Use new cache mode type in include/asm/fb.h x86: Make page cache mode a real type x86: mm: Use 2GB memory block size on large-memory x86-64 systems ...
2014-12-08x86: Replace seq_printf() with seq_puts()Rasmus Villemoes
seq_puts is a lot cheaper than seq_printf, so use that to print literal strings. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: http://lkml.kernel.org/r/1417208622-12264-1-git-send-email-linux@rasmusvillemoes.dk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-16x86: mm: Move PAT only functions to mm/pat.cThomas Gleixner
Commit e00c8cc93c1a "x86: Use new cache mode type in memtype related functions" broke the ARCH=um build. arch/x86/include/asm/cacheflush.h:67:36: error: return type is an incomplete type static inline enum page_cache_mode get_page_memtype(struct page *pg) The reason is simple. get_page_memtype() and set_page_memtype() require enum page_cache_mode now, which is defined in asm/pgtable_types.h. UM does not include that file for obvious reasons. The simple solution is to move that functions to arch/x86/mm/pat.c where the only callsites of this are located. They should have been there in the first place. Fixes: e00c8cc93c1a "x86: Use new cache mode type in memtype related functions" Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Juergen Gross <jgross@suse.com> Cc: Richard Weinberger <richard@nod.at>
2014-11-16x86: Enable PAT to use cache mode translation tablesJuergen Gross
Update the translation tables from cache mode to pgprot values according to the PAT settings. This enables changing the cache attributes of a PAT index in just one place without having to change at the users side. With this change it is possible to use the same kernel with different PAT configurations, e.g. supporting Xen. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stefan.bader@canonical.com Cc: xen-devel@lists.xensource.com Cc: ville.syrjala@linux.intel.com Cc: david.vrabel@citrix.com Cc: jbeulich@suse.com Cc: plagnioj@jcrosoft.com Cc: tomi.valkeinen@ti.com Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1415019724-4317-18-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-16x86: Use new cache mode type in memtype related functionsJuergen Gross
Instead of directly using the cache mode bits in the pte switch to using the cache mode type. Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stefan.bader@canonical.com Cc: xen-devel@lists.xensource.com Cc: konrad.wilk@oracle.com Cc: ville.syrjala@linux.intel.com Cc: david.vrabel@citrix.com Cc: jbeulich@suse.com Cc: toshi.kani@hp.com Cc: plagnioj@jcrosoft.com Cc: tomi.valkeinen@ti.com Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1415019724-4317-14-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-16x86: Use new cache mode type in mm/ioremap.cJuergen Gross
Instead of directly using the cache mode bits in the pte switch to using the cache mode type. Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stefan.bader@canonical.com Cc: xen-devel@lists.xensource.com Cc: konrad.wilk@oracle.com Cc: ville.syrjala@linux.intel.com Cc: david.vrabel@citrix.com Cc: jbeulich@suse.com Cc: toshi.kani@hp.com Cc: plagnioj@jcrosoft.com Cc: tomi.valkeinen@ti.com Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1415019724-4317-13-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-16x86: Use new cache mode type in track_pfn_remap() and track_pfn_insert()Juergen Gross
Instead of directly using the cache mode bits in the pte switch to using the cache mode type. As those are the main callers of lookup_memtype(), change this as well. Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stefan.bader@canonical.com Cc: xen-devel@lists.xensource.com Cc: konrad.wilk@oracle.com Cc: ville.syrjala@linux.intel.com Cc: david.vrabel@citrix.com Cc: jbeulich@suse.com Cc: toshi.kani@hp.com Cc: plagnioj@jcrosoft.com Cc: tomi.valkeinen@ti.com Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1415019724-4317-10-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-16x86: Use new cache mode type in mm/iomap_32.cJuergen Gross
Instead of directly using the cache mode bits in the pte switch to using the cache mode type. This requires to change io_reserve_memtype() as well. Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stefan.bader@canonical.com Cc: xen-devel@lists.xensource.com Cc: konrad.wilk@oracle.com Cc: ville.syrjala@linux.intel.com Cc: david.vrabel@citrix.com Cc: jbeulich@suse.com Cc: toshi.kani@hp.com Cc: plagnioj@jcrosoft.com Cc: tomi.valkeinen@ti.com Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1415019724-4317-9-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-16x86: Use new cache mode type in asm/pgtable.hJuergen Gross
Instead of directly using the cache mode bits in the pte switch to using the cache mode type. This requires changing some callers of is_new_memtype_allowed() to be changed as well. Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stefan.bader@canonical.com Cc: xen-devel@lists.xensource.com Cc: konrad.wilk@oracle.com Cc: ville.syrjala@linux.intel.com Cc: david.vrabel@citrix.com Cc: jbeulich@suse.com Cc: toshi.kani@hp.com Cc: plagnioj@jcrosoft.com Cc: tomi.valkeinen@ti.com Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1415019724-4317-8-git-send-email-jgross@suse.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-07x86: Do not try to sync identity map for non-mapped pagesDave Hansen
kernel_map_sync_memtype() is called from a variety of contexts. The pat.c code that calls it seems to ensure that it is not called for non-ram areas by checking via pat_pagerange_is_ram(). It is important that it only be called on the actual identity map because there *IS* no map to sync for highmem pages, or for memory holes. The ioremap.c uses are not as careful as those from pat.c, and call kernel_map_sync_memtype() on PCI space which is in the middle of the kernel identity map _range_, but is not actually mapped. This patch adds a check to kernel_map_sync_memtype() which probably duplicates some of the checks already in pat.c. But, it is necessary for the ioremap.c uses and shouldn't hurt other callers. I have reproduced this bug and this patch fixes it for me and the original bug reporter: https://lkml.org/lkml/2013/2/5/396 Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20130307163151.D9B58C4E@kernel.stglabs.ibm.com Signed-off-by: Dave Hansen <dave@sr71.net> Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2013-01-25x86, mm: Make DEBUG_VIRTUAL work earlier in bootDave Hansen
The KVM code has some repeated bugs in it around use of __pa() on per-cpu data. Those data are not in an area on which using __pa() is valid. However, they are also called early enough in boot that __vmalloc_start_set is not set, and thus the CONFIG_DEBUG_VIRTUAL debugging does not catch them. This adds a check to also verify __pa() calls against max_low_pfn, which we can use earler in boot than is_vmalloc_addr(). However, if we are super-early in boot, max_low_pfn=0 and this will trip on every call, so also make sure that max_low_pfn is set before we try to use it. With this patch applied, CONFIG_DEBUG_VIRTUAL will actually catch the bug I was chasing (and fix later in this series). I'd love to find a generic way so that any __pa() call on percpu areas could do a BUG_ON(), but there don't appear to be any nice and easy ways to check if an address is a percpu one. Anybody have ideas on a way to do this? Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20130122212430.F46F8159@kernel.stglabs.ibm.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-10-09mm, x86, pat: rework linear pfn-mmap trackingKonstantin Khlebnikov
Replace the generic vma-flag VM_PFN_AT_MMAP with x86-only VM_PAT. We can toss mapping address from remap_pfn_range() into track_pfn_vma_new(), and collect all PAT-related logic together in arch/x86/. This patch also restores orignal frustration-free is_cow_mapping() check in remap_pfn_range(), as it was before commit v2.6.28-rc8-88-g3c8bb73 ("x86: PAT: store vm_pgoff for all linear_over_vma_region mappings - v3") is_linear_pfn_mapping() checks can be removed from mm/huge_memory.c, because it already handled by VM_PFNMAP in VM_NO_THP bit-mask. [suresh.b.siddha@intel.com: Reset the VM_PAT flag as part of untrack_pfn_vma()] Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09x86, pat: separate the pfn attribute tracking for remap_pfn_range and ↵Suresh Siddha
vm_insert_pfn With PAT enabled, vm_insert_pfn() looks up the existing pfn memory attribute and uses it. Expectation is that the driver reserves the memory attributes for the pfn before calling vm_insert_pfn(). remap_pfn_range() (when called for the whole vma) will setup a new attribute (based on the prot argument) for the specified pfn range. This addresses the legacy usage which typically calls remap_pfn_range() with a desired memory attribute. For ranges smaller than the vma size (which is typically not the case), remap_pfn_range() will use the existing memory attribute for the pfn range. Expose two different API's for these different behaviors. track_pfn_insert() for tracking the pfn attribute set by vm_insert_pfn() and track_pfn_remap() for the remap_pfn_range(). This cleanup also prepares the ground for the track/untrack pfn vma routines to take over the ownership of setting PAT specific vm_flag in the 'vma'. [khlebnikov@openvz.org: Clear checks in track_pfn_remap()] [akpm@linux-foundation.org: tweak a few comments] Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Venkatesh Pallipadi <venki@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09x86, pat: remove the dependency on 'vm_pgoff' in track/untrack pfn vma routinesSuresh Siddha
'pfn' argument for track_pfn_vma_new() can be used for reserving the attribute for the pfn range. No need to depend on 'vm_pgoff' Similarly, untrack_pfn_vma() can depend on the 'pfn' argument if it is non-zero or can use follow_phys() to get the starting value of the pfn range. Also the non zero 'size' argument can be used instead of recomputing it from vma. This cleanup also prepares the ground for the track/untrack pfn vma routines to take over the ownership of setting PAT specific vm_flag in the 'vma'. [khlebnikov@openvz.org: Clear pfn to paddr conversion] Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Venkatesh Pallipadi <venki@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-30Merge branch 'x86/trampoline' into x86/urgentH. Peter Anvin
x86/trampoline contains an urgent commit which is necessarily on a newer baseline. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-05-30x86/mm/pat: Improve scaling of pat_pagerange_is_ram()John Dykstra
Function pat_pagerange_is_ram() scales poorly to large address ranges, because it probes the resource tree for each page. On a 2.6 GHz Opteron, this function consumes 34 ms for a 1 GB range. It is called twice during untrack_pfn_vma(), slowing process cleanup and handicapping the OOM killer. This replacement consumes less than 1ms, under the same conditions. Signed-off-by: John Dykstra <jdykstra@cray.com> on behalf of Cray Inc. Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1337980366.1979.6.camel@redwood [ Small stylistic cleanups and renames ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-29x86: print physical addresses consistently with other parts of kernelBjorn Helgaas
Print physical address info in a style consistent with the %pR style used elsewhere in the kernel. For example: -found SMP MP-table at [ffff8800000fce90] fce90 +found SMP MP-table at [mem 0x000fce90-0x000fce9f] mapped at [ffff8800000fce90] -initial memory mapped : 0 - 20000000 +initial memory mapped: [mem 0x00000000-0x1fffffff] -Base memory trampoline at [ffff88000009c000] 9c000 size 8192 +Base memory trampoline [mem 0x0009c000-0x0009dfff] mapped at [ffff88000009c000] -SRAT: Node 0 PXM 0 0-80000000 +SRAT: Node 0 PXM 0 [mem 0x00000000-0x7fffffff] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-06Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Ioremap: fix wrong physical address handling in PAT code x86, tlb: Clean up and correct used type x86, iomap: Fix wrong page aligned size calculation in ioremapping code x86, mm: Create symbolic index into address_markers array x86, ioremap: Fix normal ram range check x86, ioremap: Fix incorrect physical address handling in PAE mode x86-64, mm: Initialize VDSO earlier on 64 bits x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages
2010-07-29x86: Ioremap: fix wrong physical address handling in PAT codeYasuaki Ishimatsu
The following two commits fixed a problem that x86 ioremap() doesn't handle physical address higher than 32-bit properly in X86_32 PAE mode. ffa71f33a820d1ab3f2fc5723819ac60fb76080b (x86, ioremap: Fix incorrect physical address handling in PAE mode) 35be1b716a475717611b2dc04185e9d80b9cb693 (x86, ioremap: Fix normal ram range check) But these fixes are not enough, since pat_pagerange_is_ram() in PAT code also has a same problem. This patch fixes it. Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> LKML-Reference: <4C47DDCF.80300@jp.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-06-11x86, pat: Proper init of memtype subtree_max_endVenkatesh Pallipadi
subtree_max_end that was recently added to struct memtype was not getting properly initialized resulting in WARNING: kmemcheck: Caught 64-bit read from uninitialized memory in memtype_rb_augment_cb() reported here https://bugzilla.kernel.org/show_bug.cgi?id=16092 This change fixes the problem. Reported-by: Christian Casteyde <casteyde.christian@free.fr> Tested-by: Christian Casteyde <casteyde.christian@free.fr> Signed-off-by: Venkatesh Pallipadi <venki@google.com> LKML-Reference: <1276217101-11515-1-git-send-email-venki@google.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com>
2010-05-26x86, pat: Fix memory leak in free_memtypeXiaotian Feng
Reserve_memtype will allocate memory for new memtype, but in free_memtype, after the memtype erased from rbtree, the memory is not freed. Changes since V1: make rbt_memtype_erase return erased memtype so that it can be freed in free_memtype. [ hpa: not for -stable: 2.6.34 and earlier not affected ] Signed-off-by: Xiaotian Feng <dfeng@redhat.com> LKML-Reference: <1274838670-8731-1-git-send-email-dfeng@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Jack Steiner <steiner@sgi.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-05-18Merge branch 'x86-pat-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, pat: Update the page flags for memtype atomically instead of using memtype_lock x86, pat: In rbt_memtype_check_insert(), update new->type only if valid x86, pat: Migrate to rbtree only backend for pat memtype management x86, pat: Preparatory changes in pat.c for bigger rbtree change rbtree: Add support for augmented rbtrees
2010-04-23x86, pat: Update the page flags for memtype atomically instead of using ↵Robin Holt
memtype_lock While testing an application using the xpmem (out of kernel) driver, we noticed a significant page fault rate reduction of x86_64 with respect to ia64. For one test running with 32 cpus, one thread per cpu, it took 01:08 for each of the threads to vm_insert_pfn 2GB worth of pages. For the same test running on 256 cpus, one thread per cpu, it took 14:48 to vm_insert_pfn 2 GB worth of pages. The slowdown was tracked to lookup_memtype which acquires the spinlock memtype_lock. This heavily contended lock was slowing down vm_insert_pfn(). With the cmpxchg on page->flags method, both the 32 cpu and 256 cpu cases take approx 00:01.3 seconds to complete. Signed-off-by: Robin Holt <holt@sgi.com> LKML-Reference: <20100423153627.751194346@gulag1.americas.sgi.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@gmail.com> Cc: Rafael Wysocki <rjw@novell.com> Reviewed-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-02-18x86, pat: Migrate to rbtree only backend for pat memtype managementPallipadi, Venkatesh
Move pat backend to fully rbtree based implementation from the existing rbtree and linked list hybrid. New rbtree based solution uses interval trees (augmented rbtrees) in order to store the PAT ranges. The new code seprates out the pat backend to pat_rbtree.c file, making is cleaner. The change also makes the PAT lookup, reserve and free operations more optimal, as we don't have to traverse linear linked list of few tens of entries in normal case. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> LKML-Reference: <20100210232607.GB11465@linux-os.sc.intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-18x86, pat: Preparatory changes in pat.c for bigger rbtree changevenkatesh.pallipadi@intel.com
Minor changes in pat.c to cleanup code and make it smoother to introduce bigger rbtree only change in the following patch. The changes are cleaup only and should not have any functional impact. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> LKML-Reference: <20100210195909.792781000@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-10vfs: Implement proper O_SYNC semanticsChristoph Hellwig
While Linux provided an O_SYNC flag basically since day 1, it took until Linux 2.4.0-test12pre2 to actually get it implemented for filesystems, since that day we had generic_osync_around with only minor changes and the great "For now, when the user asks for O_SYNC, we'll actually give O_DSYNC" comment. This patch intends to actually give us real O_SYNC semantics in addition to the O_DSYNC semantics. After Jan's O_SYNC patches which are required before this patch it's actually surprisingly simple, we just need to figure out when to set the datasync flag to vfs_fsync_range and when not. This patch renames the existing O_SYNC flag to O_DSYNC while keeping it's numerical value to keep binary compatibility, and adds a new real O_SYNC flag. To guarantee backwards compatiblity it is defined as expanding to both the O_DSYNC and the new additional binary flag (__O_SYNC) to make sure we are backwards-compatible when compiled against the new headers. This also means that all places that don't care about the differences can just check O_DSYNC and get the right behaviour for O_SYNC, too - only places that actuall care need to check __O_SYNC in addition. Drivers and network filesystems have been updated in a fail safe way to always do the full sync magic if O_DSYNC is set. The few places setting O_SYNC for lower layers are kept that way for now to stay failsafe. We enforce that O_DSYNC is set when __O_SYNC is set early in the open path to make sure we always get these sane options. Note that parisc really screwed up their headers as they already define a O_DSYNC that has always been a no-op. We try to repair it by using it for the new O_DSYNC and redefinining O_SYNC to send both the traditional O_SYNC numerical value _and_ the O_DSYNC one. Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Grant Grundler <grundler@parisc-linux.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Dilger <adilger@sun.com> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: Kyle McMartin <kyle@mcmartin.ca> Acked-by: Ulrich Drepper <drepper@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jan Kara <jack@suse.cz>
2009-12-08Merge branch 'x86-pat-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: pat: Remove ioremap_default() x86: pat: Clean up req_type special case for reserve_memtype() x86: Relegate CONFIG_PAT and CONFIG_MTRR configurability to EMBEDDED
2009-11-26x86/pat: Trivial: don't create debugfs for memtype if pat is disabledXiaotian Feng
If pat is disabled (boot with nopat), there's no need to create debugfs for it, it's empty all the time. Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <1259236428-16329-1-git-send-email-dfeng@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23x86, platform: Change is_untracked_pat_range() to bool; cleanup initH. Peter Anvin
- Change is_untracked_pat_range() to return bool. - Clean up the initialization of is_untracked_pat_range() -- by default, we simply point it at is_ISA_range() directly. - Move is_untracked_pat_range to the end of struct x86_platform, since it is the newest field. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jack Steiner <steiner@sgi.com> LKML-Reference: <20091119202341.GA4420@sgi.com>
2009-11-23x86, mm: is_untracked_pat_range() takes a normal semiclosed rangeH. Peter Anvin
is_untracked_pat_range() -- like its components, is_ISA_range() and is_GRU_range(), takes a normal semiclosed interval (>=, <) whereas the PAT code called it as if it took a closed range (>=, <=). Fix. Although this is a bug, I believe it is non-manifest, simply because none of the callers will call this with non-page-aligned addresses. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <20091119202341.GA4420@sgi.com>
2009-11-23x86: UV SGI: Don't track GRU space in PATJack Steiner
GRU space is always mapped as WB in the page table. There is no need to track the mappings in the PAT. This also eliminates the "freeing invalid memtype" messages when the GRU space is unmapped. Signed-off-by: Jack Steiner <steiner@sgi.com> LKML-Reference: <20091119202341.GA4420@sgi.com> [ v2: fix build failure ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-10x86: pat: Clean up req_type special case for reserve_memtype()Xiaotian Feng
Commit: b6ff32d: x86, PAT: Consolidate code in pat_x_mtrr_type() and reserve_memtype() consolidated code in pat_x_mtrr_type() and reserve_memtype(), which removed the special case (req_type is -1) for the PAT-enabled part. We should also change comments and the PAT-disabled part. Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> LKML-Reference: <1257844987-7906-1-git-send-email-dfeng@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-24x86: Reduce verbosity of "PAT enabled" kernel messageRoland Dreier
On modern systems, the kernel prints the message x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106 once for every CPU. This gets kind of ridiculous on huge systems; for example, on a 64-thread system I was lucky enough to get: dmesg| grep 'PAT enabled' | wc 64 704 5174 There is already a BUG() if non-boot CPUs have PAT capabilities that don't match the boot CPU, so just print the message on the boot CPU. (I kept the print after the wrmsrl() that enables PAT, so that the log output continues to mean that the system survived enabling PAT on the boot CPU) Signed-off-by: Roland Dreier <rolandd@cisco.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> LKML-Reference: <adavdj92sso.fsf@cisco.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, pat: don't use rb-tree based lookup in reserve_memtype() x86: Increase MIN_GAP to include randomized stack
2009-09-17x86, pat: don't use rb-tree based lookup in reserve_memtype()Suresh Siddha
Recent enhancement of rb-tree based lookup exposed a bug with the lookup mechanism in the reserve_memtype() which ensures that there are no conflicting memtype requests for the memory range. memtype_rb_search() returns an entry which has a start address <= new start address. And from here we traverse the linear linked list to check if there any conflicts with the existing mappings. As the rbtree is based on the start address of the memory range, it is quite possible that we have several overlapped mappings whose start address is much less than new requested start but the end is >= new requested end. This results in conflicting memtype mappings. Same bug exists with the old code which uses cached_entry from where we traverse the linear linked list. But the new rb-tree code exposes this bug fairly easily. For now, don't use the memtype_rb_search() and always start the search from the head of linear linked list in reserve_memtype(). Linear linked list for most of the systems grow's to few 10's of entries(as we track memory type of RAM pages using struct page). So we should be ok for now. We still retain the rbtree and use it to speed up free_memtype() which doesn't have the same bug(as we know what exactly we are searching for in free_memtype). Also use list_for_each_entry_from() in free_memtype() so that we start the search from rb-tree lookup result. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> LKML-Reference: <1253136483.4119.12.camel@sbs-t61.sc.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-15Merge branch 'x86-pat-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, pat: Fix cacheflush address in change_page_attr_set_clr() mm: remove !NUMA condition from PAGEFLAGS_EXTENDED condition set x86: Fix earlyprintk=dbgp for machines without NX x86, pat: Sanity check remap_pfn_range for RAM region x86, pat: Lookup the protection from memtype list on vm_insert_pfn() x86, pat: Add lookup_memtype to get the current memtype of a paddr x86, pat: Use page flags to track memtypes of RAM pages x86, pat: Generalize the use of page flag PG_uncached x86, pat: Add rbtree to do quick lookup in memtype tracking x86, pat: Add PAT reserve free to io_mapping* APIs x86, pat: New i/f for driver to request memtype for IO regions x86, pat: ioremap to follow same PAT restrictions as other PAT users x86, pat: Keep identity maps consistent with mmaps even when pat_disabled x86, mtrr: make mtrr_aps_delayed_init static bool x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init generic-ipi: Allow cpus not yet online to call smp_call_function with irqs disabled x86: Fix an incorrect argument of reserve_bootmem() x86: Fix system crash when loading with "reservetop" parameter
2009-09-14Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Make memtype_seq_ops const x86: uv: Clean up uv_ptc_init(), use proc_create() x86: Use printk_once() x86/cpu: Clean up various files a bit x86: Remove duplicated #include x86, ipi: Clean up safe_smp_processor_id() by using the cpu_has_apic() macro helper x86: Clean up idt_descr and idt_tableby using NR_VECTORS instead of hardcoded number x86: Further clean up of mtrr/generic.c x86: Clean up mtrr/main.c x86: Clean up mtrr/state.c x86: Clean up mtrr/mtrr.h x86: Clean up mtrr/if.c x86: Clean up mtrr/generic.c x86: Clean up mtrr/cyrix.c x86: Clean up mtrr/cleanup.c x86: Clean up mtrr/centaur.c x86: Clean up mtrr/amd.c: x86: ds.c fix invalid assignment
2009-09-06x86: Make memtype_seq_ops constTobias Klauser
Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-26Merge branch 'x86/urgent' into x86/patH. Peter Anvin
Reason: Change to is_new_memtype_allowed() in x86/urgent Resolved semantic conflicts in: arch/x86/mm/pat.c arch/x86/mm/ioremap.c Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26x86, pat: Sanity check remap_pfn_range for RAM regionVenkatesh Pallipadi
Add sanity check for remap_pfn_range of RAM regions using lookup_memtype(). Previously, we did not have anyway to get the type of RAM memory regions as they were tracked using a single bit in page_struct (WB, nonWB). Now we can get the actual type from page struct (WB, WC, UC_MINUS) and make sure the requester gets that type. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26x86, pat: Lookup the protection from memtype list on vm_insert_pfn()Venkatesh Pallipadi
Lookup the reserved memtype during vm_insert_pfn and use that memtype for the new mapping. This takes care or handling of vm_insert_pfn() interface in track_pfn_vma*/untrack_pfn_vma. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26x86, pat: Add lookup_memtype to get the current memtype of a paddrVenkatesh Pallipadi
Add a new routine lookup_memtype() to get the current memtype based on the PAT reserves and frees. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26x86, pat: Use page flags to track memtypes of RAM pagesVenkatesh Pallipadi
Change reserve_ram_pages_type and free_ram_pages_type to use 2 page flags to track UC_MINUS, WC, WB and default types. Previous RAM tracking just tracked WB or NonWB, which was not complete and did not allow tracking of RAM fully and there was no way to get the actual type reserved by looking at the page flags. We use the memtype_lock spinlock for atomicity in dealing with memtype tracking in struct page. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26x86, pat: Add rbtree to do quick lookup in memtype trackingVenkatesh Pallipadi
PAT memtype tracking uses a linear link list to keep track of IO (non-RAM) regions and their memtypes. The code used a last_accessed pointer as a cache to speedup the lookup. As per discussions with H. Peter Anvin a while back, having a rbtree here will avoid bad performances in pathological cases where we may end up with huge linked list. This may not add any noticable performance speedup in normal case as the number of entires in PAT memtype list tend to be ~20-30 range. The patch removes the "cached_entry" logic as with rbtree we have more generic way of speeding up the lookup. With this patch, we use rbtree to do the quick lookup. We still use linked list as the memtype range tracked can be of different sizes and can overlap in different ways. We also keep track of usage counts with linked list. Example: Multiple ioremaps with different sizes uncached-minus @ 0xfffff00000-0xfffff04000 uncached-minus @ 0xfffff02000-0xfffff03000 And one userlevel mmap and the thread forks a new process uncached-minus @ 0xbf453000-0xbf454000 uncached-minus @ 0xbf453000-0xbf454000 Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26x86, pat: New i/f for driver to request memtype for IO regionsVenkatesh Pallipadi
Add new routines to request memtype for IO regions. This will currently be a backend for io_mapping_* routines. But, it can also be made available to drivers directly in future, in case it is needed. reserve interface reserves the memory, makes sure we have a compatible memory type available and keeps the identity map in sync when needed. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26x86, pat: Keep identity maps consistent with mmaps even when pat_disabledVenkatesh Pallipadi
Make reserve_memtype internally take care of pat disabled case and fallback to default return values. Remove the specific pat_disabled checks in track_* routines. Change kernel_map_sync_memtype to sync identity map even when pat_disabled. This change ensures that, even for pat_disabled case, we take care of keeping identity map in sync. Before this patch, in pat disabled case, ioremap() keeps the identity maps in sync and other APIs like pci and /dev/mem mmap don't, which is not a very consistent behavior. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-17x86, pat: Allow ISA memory range uncacheable mapping requestsSuresh Siddha
Max Vozeler reported: > Bug 13877 - bogl-term broken with CONFIG_X86_PAT=y, works with =n > > strace of bogl-term: > 814 mmap2(NULL, 65536, PROT_READ|PROT_WRITE, MAP_SHARED, 4, 0) > = -1 EAGAIN (Resource temporarily unavailable) > 814 write(2, "bogl: mmaping /dev/fb0: Resource temporarily unavailable\n", > 57) = 57 PAT code maps the ISA memory range as WB in the PAT attribute, so that fixed range MTRR registers define the actual memory type (UC/WC/WT etc). But the upper level is_new_memtype_allowed() API checks are failing, as the request here is for UC and the return tracked type is WB (Tracked type is WB as MTRR type for this legacy range potentially will be different for each 4k page). Fix is_new_memtype_allowed() by always succeeding the ISA address range checks, as the null PAT (WB) and def MTRR fixed range register settings satisfy the memory type needs of the applications that map the ISA address range. Reported-and-Tested-by: Max Vozeler <xam@debian.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>