- 22 Oct, 2007 15 commits
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Keshavamurthy, Anil S authored
Intel IOMMU driver needs memory during DMA map calls to setup its internal page tables and for other data structures. As we all know that these DMA map calls are mostly called in the interrupt context or with the spinlock held by the upper level drivers(network/storage drivers), so in order to avoid any memory allocation failure due to low memory issues, this patch makes memory allocation by temporarily setting PF_MEMALLOC flags for the current task before making memory allocation calls. We evaluated mempools as a backup when kmem_cache_alloc() fails and found that mempools are really not useful here because 1) We don't know for sure how much to reserve in advance 2) And mempools are not useful for GFP_ATOMIC case (as we call memory alloc functions with GFP_ATOMIC) (akpm: point 2 is wrong...) With PF_MEMALLOC flag set in the current->flags, the VM subsystem avoids any watermark checks before allocating memory thus guarantee'ing the memory till the last free page. Further, looking at the code in mm/page_alloc.c in __alloc_pages() function, looks like this flag is useful only in the non-interrupt context. If we are in the interrupt context and memory allocation in IOMMU driver fails for some reason, then the DMA map api's will return failure and it is up to the higher level drivers to retry. Suppose, if upper level driver programs the controller with the buggy DMA virtual address, the IOMMU will block that DMA transaction when that happens thus preventing any corruption to main memory. So far in our test scenario, we were unable to create any memory allocation failure inside dma map api calls. Signed-off-by:Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Christoph Lameter <clameter@sgi.com> Cc: Greg KH <greg@kroah.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Keshavamurthy, Anil S authored
Actual intel IOMMU driver. Hardware spec can be found at: http://www.intel.com/technology/virtualization This driver sets X86_64 'dma_ops', so hook into standard DMA APIs. In this way, PCI driver will get virtual DMA address. This change is transparent to PCI drivers. [akpm@linux-foundation.org: remove unneeded cast] [akpm@linux-foundation.org: build fix] [bunk@stusta.de: fix duplicate CONFIG_DMAR Makefile line] Signed-off-by:
Adrian Bunk <bunk@stusta.de> Signed-off-by:
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Keshavamurthy, Anil S authored
This code implements a generic IOVA allocation and management. As per Dave's suggestion we are now allocating IO virtual address from Higher DMA limit address rather than lower end address and this eliminated the need to preserve the IO virtual address for multiple devices sharing the same domain virtual address. Also this code uses red black trees to store the allocated and reserved iova nodes. This showed a good performance improvements over previous linear linked list. [akpm@linux-foundation.org: remove inlines] [akpm@linux-foundation.org: coding style fixes] Signed-off-by:
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Keshavamurthy, Anil S authored
Introduce the size param for clflush_cache_range(). Signed-off-by:
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Keshavamurthy, Anil S authored
When devices are under a p2p bridge, upstream transactions get replaced by the device id of the bridge as it owns the PCIE transaction. Hence its necessary to setup translations on behalf of the bridge as well. Due to this limitation all devices under a p2p share the same domain in a DMAR. We just cache the type of device, if its a native PCIe device or not for later use. [akpm@linux-foundation.org: BUG_ON -> WARN_ON+recover] Signed-off-by:
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Keshavamurthy, Anil S authored
This patch supports the upcomming Intel IOMMU hardware a.k.a. Intel(R) Virtualization Technology for Directed I/O Architecture and the hardware spec for the same can be found here http://www.intel.com/technology/virtualization/index.htm FAQ! (questions from akpm, answers from ak) > So... what's all this code for? > > I assume that the intent here is to speed things up under Xen, etc? Yes in some cases, but not this code. That would be the Xen version of this code that could potentially assign whole devices to guests. I expect this to be only useful in some special cases though because most hardware is not virtualizable and you typically want an own instance for each guest. Ok at some point KVM might implement this too; i likely would use this code for this. > Do we > have any benchmark results to help us to decide whether a merge would be > justified? The main advantage for doing it in the normal kernel is not performance, but more safety. Broken devices won't be able to corrupt memory by doing random DMA. Unfortunately that doesn't work for graphics yet, for that need user space interfaces for the X server are needed. There are some potential performance benefits too: - When you have a device that cannot address the complete address range an IOMMU can remap its memory instead of bounce buffering. Remapping is likely cheaper than copying. - The IOMMU can merge sg lists into a single virtual block. This could potentially speed up SG IO when the device is slow walking SG lists. [I long ago benchmarked 5% on some block benchmark with an old MPT Fusion; but it probably depends a lot on the HBA] And you get better driver debugging because unexpected memory accesses from the devices will cause a trappable event. > > Does it slow anything down? It adds more overhead to each IO so yes. This patch: Add support for early detection and parsing of DMAR's (DMA Remapping) reported to OS via ACPI tables. DMA remapping(DMAR) devices support enables independent address translations for Direct Memory Access(DMA) from Devices. These DMA remapping devices are reported via ACPI tables and includes pci device scope covered by these DMA remapping device. For detailed info on the specification of "Intel(R) Virtualization Technology for Directed I/O Architecture" please see http://www.intel.com/technology/virtualization/index.htmSigned-off-by:
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Jan Kara authored
With 64KB blocksize, a directory entry can have size 64KB which does not fit into 16 bits we have for entry length. So we store 0xffff instead and convert the value when read from / written to disk. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by:
Jan Kara <jack@suse.cz> Cc: <linux-ext4@vger.kernel.org> Signed-off-by:
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J. Bruce Fields authored
Well, it's not especially important that target->d_iname get the contents of dentry->d_iname, but it's important that it get initialized with *something*, otherwise we're just exposing some random piece of memory to anyone who reads the link at /proc/<pid>/fd/<fd> for the deleted file, when it's still held open by someone. I've run a test program that copies a short (<36 character) name ontop of a long (>=36 character) name and see that the first time I run it, without this patch, I get unpredicatable results out of /proc/<pid>/fd/<fd>. Signed-off-by:
J. Bruce Fields <bfields@citi.umich.edu> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by:
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Serge E. Hallyn authored
Simplify the vfs_cap_data structure. Also fix get_file_caps which was declaring __le32 v1caps[XATTR_CAPS_SZ] on the stack, but XATTR_CAPS_SZ is already * sizeof(__le32). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by:
Serge E. Hallyn <serue@us.ibm.com> Cc: Andrew Morgan <morgan@kernel.org> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by:
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Yasunori Goto authored
Fix a panic due to access NULL pointer of kmem_cache_node at discard_slab() after memory online. When memory online is called, kmem_cache_nodes are created for all SLUBs for new node whose memory are available. slab_mem_going_online_callback() is called to make kmem_cache_node() in callback of memory online event. If it (or other callbacks) fails, then slab_mem_offline_callback() is called for rollback. In memory offline, slab_mem_going_offline_callback() is called to shrink all slub cache, then slab_mem_offline_callback() is called later. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: locking fix] [akpm@linux-foundation.org: build fix] Signed-off-by:
Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by:
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Yasunori Goto authored
Current memory notifier has some defects yet. (Fortunately, nothing uses it.) This patch is to fix and rearrange for them. - Add information of start_pfn, nr_pages, and node id if node status is changes from/to memoryless node for callback functions. Callbacks can't do anything without those information. - Add notification going-online status. It is necessary for creating per node structure before the node's pages are available. - Move GOING_OFFLINE status notification after page isolation. It is good place for return memory like cache for callback, because returned page is not used again. - Make CANCEL events for rollingback when error occurs. - Delete MEM_MAPPING_INVALID notification. It will be not used. - Fix compile error of (un)register_memory_notifier(). Signed-off-by: -
Yasunori Goto authored
Add description about event notification callback routine to the document Signed-off-by:
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Rusty Russell authored
This patch uses the updated boot protocol to do paravirtualized boot. If the boot version is >= 2.07, then it will do two things: 1. Check the bootparams loadflags to see if we should reload the segment registers and clear interrupts. This is appropriate for normal native boot and some paravirtualized environments, but inapproprate for others. 2. Check the hardware architecture, and dispatch to the appropriate kernel entrypoint. If the bootloader doesn't set this, then we simply do the normal boot sequence. Signed-off-by:Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by:
Rusty Russell <rusty@rustcorp.com.au> Acked-by:
H. Peter Anvin <hpa@zytor.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@in.ibm.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Zachary Amsden <zach@vmware.com> Cc: Andi Kleen <ak@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by:
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Rusty Russell authored
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Rusty Russell authored
Updates for version 2.07 of the boot protocol. This includes: load_flags.KEEP_SEGMENTS- flag to request/inhibit segment reloads hardware_subarch - what subarchitecture we're booting under hardware_subarch_data - per-architecture data The intention of these changes is to make booting a paravirtualized kernel work via the normal Linux boot protocol. Signed-off-by:
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- 21 Oct, 2007 25 commits
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Trond Myklebust authored
Signed-off-by:Trond Myklebust <Trond.Myklebust@netapp.com>
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Trond Myklebust authored
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Linus Torvalds authored
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/cooloney/blackfin-2.6: Blackfin arch: update boards files Blackfin arch: dma add some API and cleanup bf54x DMA definition Blackfin arch: cleanup and promote the general purpose timers api to a core blackfin component Blackfin arch: add a cheesy install target Blackfin arch: add functions for converting between sclks and usecs Blackfin arch: add assembly function for doing 64bit unsigned division Blackfin arch: -mno-fdpic works Blackfin arch: use "char bfin_board_name[]" rather than "char *bfin_board_name" per discussion on lkml as the former uses less storage Blackfin arch: Fixing Bug: balance calls to get_task_mm with corresponding mmput calls Blackfin serial driver Kconfig: depend on DMA not being enabled rather than a specific DMA size Blackfin arch: Fix bug: missing CHIPID register field definition of BF54x Blackfin arch: Fix up /proc/cpuinfo so it is like everyone else Blackfin arch: Optimization - no need to make additional math here Blackfin arch: force irq_flags into the .data section Blackfin arch BF548 defconfig: enable watchdog by default Blackfin arch: add new processor ADSP-BF52x arch/mach support
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-currentLinus Torvalds authored
* 'audit.b43' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current: [PATCH] audit: watching subtrees [PATCH] new helper - inotify_evict_watch() [PATCH] new helper - inotify_clone_watch() [PATCH] new helpers - collect_mounts() and release_collected_mounts() [PATCH] pass dentry to audit_inode()/audit_inode_child()
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Nick Piggin authored
This path mustn't have been tested :( I did attempt to exercise it by injecting failures here, but I suspect PageMappedToDisk may have been getting in the way. Will need more of a look, although I think nobh mode is OK for an -rc1 (it shouldn't eat anyone's data). Commit 03158cd7 ("fs: restore nobh") introcduced a NULL deref. Spotted by the Coverity checker. Signed-off-by:
Nick Piggin <npiggin@suse.de> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Bryan Wu authored
Signed-off-by:Bryan Wu <bryan.wu@analog.com>
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Bryan Wu authored
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Mike Frysinger authored
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Mike Frysinger <michael.frysinger@analog.com> Signed-off-by:
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Mike Frysinger authored
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Mike Frysinger authored
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Mike Frysinger authored
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Mike Frysinger authored
now that -mno-fdpic works, force it on so that we can use any blackfin toolchain to build up the kernel and kernel modules wrap -mno-fdpic in $(call cc-option,-mno-fdpic) so that older toolchains will still work Signed-off-by:
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Mike Frysinger authored
Blackfin arch: use "char bfin_board_name[]" rather than "char *bfin_board_name" per discussion on lkml as the former uses less storage Signed-off-by:
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Bernd Schmidt authored
We must balance calls to get_task_mm with corresponding mmput calls, otherwise refcounting is screwed up and mms don't get freed when their task exits. Signed-off-by: -
Mike Frysinger authored
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Bryan Wu authored
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Robin Getz authored
Fix up /proc/cpuinfo so it is like everyone else, and gets parsed by various applications properly. Still needs some tweaking on parts without full L1 sram, like 532, 531, so it doesn't print out L1 bank info that doesn't exist. Signed-off-by:
Robin Getz <robin.getz@analog.com> Signed-off-by:
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Michael Hennerich authored
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Michael Hennerich <michael.hennerich@analog.com> Signed-off-by:
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Mike Frysinger authored
force irq_flags into the .data section by initializing it to the hardware masks that cannot be disabled. this way if we use irq enable/disable functions before the .bss has been zeroed out (as does our l1 relocate/dma functions), we dont hit a problem where bss contains bogus crap. Signed-off-by:
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Mike Frysinger authored
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Michael Hennerich authored
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Al Viro authored
New kind of audit rule predicates: "object is visible in given subtree". The part that can be sanely implemented, that is. Limitations: * if you have hardlink from outside of tree, you'd better watch it too (or just watch the object itself, obviously) * if you mount something under a watched tree, tell audit that new chunk should be added to watched subtrees * if you umount something in a watched tree and it's still mounted elsewhere, you will get matches on events happening there. New command tells audit to recalculate the trees, trimming such sources of false positives. Note that it's _not_ about path - if something mounted in several places (multiple mount, bindings, different namespaces, etc.), the match does _not_ depend on which one we are using for access. Signed-off-by:Al Viro <viro@zeniv.linux.org.uk>
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Al Viro authored
Kicks the watch out without dropping it. Called under ->inotify_mutex Signed-off-by: -
Al Viro authored
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Al Viro authored
Get a snapshot of a subtree, creating private clones of vfsmounts for all its components and release such snapshot resp. Signed-off-by:
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