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2013-03-19xen-blkback: don't store dev_bus_addrRoger Pau Monne
dev_bus_addr returned in the grant ref map operation is the mfn of the passed page, there's no need to store it in the persistent grant entry, since we can always get it provided that we have the page. This reduces the memory overhead of persistent grants in blkback. While at it, rename the 'seg[i].buf' to be 'seg[i].offset' as it makes much more sense - as we use that value in bio_add_page which as the fourth argument expects the offset. We hadn't used the physical address as part of this at all. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: xen-devel@lists.xen.org [v1: s/buf/offset/] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-19xen-blkback: fix foreach_grant_safe to handle empty listsRoger Pau Monne
We may use foreach_grant_safe in the future with empty lists, so make sure we can handle them. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: xen-devel@lists.xen.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-18xen-blkback: fix dispatch_rw_block_io() error pathJan Beulich
Commit 7708992 ("xen/blkback: Seperate the bio allocation and the bio submission") consolidated the pendcnt updates to just a single write, neglecting the fact that the error path relied on it getting set to 1 up front (such that the decrement in __end_block_io_op() would actually drop the count to zero, triggering the necessary cleanup actions). Also remove a misleading and a stale (after said commit) comment. CC: stable@vger.kernel.org Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-11xen/blkback: Change statistics counter types to unsignedZoltan Kiss
These values shouldn't be negative, but after an overflow their value can turn into negative, if they are signed. xentop can show bogus values in this case. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Reported-by: Ichiro Ogino <ichiro.ogino@citrix.co.jp> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-11xen/blkback: correctly respond to unknown, non-native requestsDavid Vrabel
If the frontend is using a non-native protocol (e.g., a 64-bit frontend with a 32-bit backend) and it sent an unrecognized request, the request was not translated and the response would have the incorrect ID. This may cause the frontend driver to behave incorrectly or crash. Since the ID field in the request is always in the same place, regardless of the request type we can get the correct ID and make a valid response (which will report BLKIF_RSP_EOPNOTSUPP). This bug affected 64-bit SLES 11 guests when using a 32-bit backend. This guest does a BLKIF_OP_RESERVED_1 (BLKIF_OP_PACKET in the SLES source) and would crash in blkif_int() as the ID in the response would be invalid. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-01xen/xen-blkback: preq.dev is used without initializedChen Gang
If call xen_vbd_translate failed, the preq.dev will be not initialized. Use blkif->vbd.pdevice instead (still better to print relative info). Note that before commit 01c681d4c70d64cb72142a2823f27c4146a02e63 (xen/blkback: Don't trust the handle from the frontend.) the value bogus, as it was the guest provided value from req->u.rw.handle rather than the actual device. Signed-off-by: Chen Gang <gang.chen@asianux.com> Acked-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-19xen-blkback: use balloon pages for persistent grantsRoger Pau Monne
With current persistent grants implementation we are not freeing the persistent grants after we disconnect the device. Since grant map operations change the mfn of the allocated page, and we can no longer pass it to __free_page without setting the mfn to a sane value, use balloon grant pages instead, as the gntdev device does. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: stable@vger.kernel.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-19xen/blkback: Don't trust the handle from the frontend.Konrad Rzeszutek Wilk
The 'handle' is the device that the request is from. For the life-time of the ring we copy it from a request to a response so that the frontend is not surprised by it. But we do not need it - when we start processing I/Os we have our own 'struct phys_req' which has only most essential information about the request. In fact the 'vbd_translate' ends up over-writing the preq.dev with a value from the backend. This assignment of preq.dev with the 'handle' value is superfluous so lets not do it. Cc: stable@vger.kernel.org Acked-by: Jan Beulich <jbeulich@suse.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-19xen-blkback: do not leak mode propertyJan Beulich
"be->mode" is obtained from xenbus_read(), which does a kmalloc() for the message body. The short string is never released, so do it along with freeing "be" itself, and make sure the string isn't kept when backend_changed() doesn't complete successfully (which made it desirable to slightly re-structure that function, so that the error cleanup can be done in one place). Reported-by: Olaf Hering <olaf@aepfle.de> CC: stable@vger.kernel.org Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-12-19Merge branch 'stable/for-jens-3.8' of ↵Jens Axboe
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus Konrad writes: Please git pull the following branch: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/for-jens-3.8 which has a bug-fix to the xen-blkfront and xen-blkback driver when using the persistent mode. An issue was discovered where LVM disks could not be read correctly and this fixes it. There is also a change in llist.h which has been blessed by akpm.
2012-12-17Merge branch 'for-3.8/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver update from Jens Axboe: "Now that the core bits are in, here are the driver bits for 3.8. The branch contains: - A huge pile of drbd bits that were dumped from the 3.7 merge window. Following that, it was both made perfectly clear that there is going to be no more over-the-wall pulls and how the situation on individual pulls can be improved. - A few cleanups from Akinobu Mita for drbd and cciss. - Queue improvement for loop from Lukas. This grew into adding a generic interface for waiting/checking an even with a specific lock, allowing this to be pulled out of md and now loop and drbd is also using it. - A few fixes for xen back/front block driver from Roger Pau Monne. - Partition improvements from Stephen Warren, allowing partiion UUID to be used as an identifier." * 'for-3.8/drivers' of git://git.kernel.dk/linux-block: (609 commits) drbd: update Kconfig to match current dependencies drbd: Fix drbdsetup wait-connect, wait-sync etc... commands drbd: close race between drbd_set_role and drbd_connect drbd: respect no-md-barriers setting also when changed online via disk-options drbd: Remove obsolete check drbd: fixup after wait_even_lock_irq() addition to generic code loop: Limit the number of requests in the bio list wait: add wait_event_lock_irq() interface xen-blkfront: free allocated page xen-blkback: move free persistent grants code block: partition: msdos: provide UUIDs for partitions init: reduce PARTUUID min length to 1 from 36 block: store partition_meta_info.uuid as a string cciss: use check_signature() cciss: cleanup bitops usage drbd: use copy_highpage drbd: if the replication link breaks during handshake, keep retrying drbd: check return of kmalloc in receive_uuids drbd: Broadcast sync progress no more often than once per second drbd: don't try to clear bits once the disk has failed ...
2012-12-07xen-blkback: implement safe iterator for the list of persistent grantsRoger Pau Monne
Change foreach_grant iterator to a safe version, that allows freeing the element while iterating. Also move the free code in free_persistent_gnts to prevent freeing the element before the rb_next call. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad@kernel.org> Cc: xen-devel@lists.xen.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-26xen-blkback: move free persistent grants codeRoger Pau Monne
Move the code that frees persistent grants from the red-black tree to a function. This will make it easier for other consumers to move this to a common place. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-04xen/blkback: persistent-grants fixesRoger Pau Monne
This patch contains fixes for persistent grants implementation v2: * handle == 0 is a valid handle, so initialize grants in blkback setting the handle to BLKBACK_INVALID_HANDLE instead of 0. Reported by Konrad Rzeszutek Wilk. * new_map is a boolean, use "true" or "false" instead of 1 and 0. Reported by Konrad Rzeszutek Wilk. * blkfront announces the persistent-grants feature as feature-persistent-grants, use feature-persistent instead which is consistent with blkback and the public Xen headers. * Add a consistency check in blkfront to make sure we don't try to access segments that have not been set. Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Roger Pau Monne <roger.pau@citrix.com> [v1: The new_map int->bool had already been changed] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30xen/blkback: Persistent grant maps for xen blk driversRoger Pau Monne
This patch implements persistent grants for the xen-blk{front,back} mechanism. The effect of this change is to reduce the number of unmap operations performed, since they cause a (costly) TLB shootdown. This allows the I/O performance to scale better when a large number of VMs are performing I/O. Previously, the blkfront driver was supplied a bvec[] from the request queue. This was granted to dom0; dom0 performed the I/O and wrote directly into the grant-mapped memory and unmapped it; blkfront then removed foreign access for that grant. The cost of unmapping scales badly with the number of CPUs in Dom0. An experiment showed that when Dom0 has 24 VCPUs, and guests are performing parallel I/O to a ramdisk, the IPIs from performing unmap's is a bottleneck at 5 guests (at which point 650,000 IOPS are being performed in total). If more than 5 guests are used, the performance declines. By 10 guests, only 400,000 IOPS are being performed. This patch improves performance by only unmapping when the connection between blkfront and back is broken. On startup blkfront notifies blkback that it is using persistent grants, and blkback will do the same. If blkback is not capable of persistent mapping, blkfront will still use the same grants, since it is compatible with the previous protocol, and simplifies the code complexity in blkfront. To perform a read, in persistent mode, blkfront uses a separate pool of pages that it maps to dom0. When a request comes in, blkfront transmutes the request so that blkback will write into one of these free pages. Blkback keeps note of which grefs it has already mapped. When a new ring request comes to blkback, it looks to see if it has already mapped that page. If so, it will not map it again. If the page hasn't been previously mapped, it is mapped now, and a record is kept of this mapping. Blkback proceeds as usual. When blkfront is notified that blkback has completed a request, it memcpy's from the shared memory, into the bvec supplied. A record that the {gref, page} tuple is mapped, and not inflight is kept. Writes are similar, except that the memcpy is peformed from the supplied bvecs, into the shared pages, before the request is put onto the ring. Blkback stores a mapping of grefs=>{page mapped to by gref} in a red-black tree. As the grefs are not known apriori, and provide no guarantees on their ordering, we have to perform a search through this tree to find the page, for every gref we receive. This operation takes O(log n) time in the worst case. In blkfront grants are stored using a single linked list. The maximum number of grants that blkback will persistenly map is currently set to RING_SIZE * BLKIF_MAX_SEGMENTS_PER_REQUEST, to prevent a malicios guest from attempting a DoS, by supplying fresh grefs, causing the Dom0 kernel to map excessively. If a guest is using persistent grants and exceeds the maximum number of grants to map persistenly the newly passed grefs will be mapped and unmaped. Using this approach, we can have requests that mix persistent and non-persistent grants, and we need to handle them correctly. This allows us to set the maximum number of persistent grants to a lower value than RING_SIZE * BLKIF_MAX_SEGMENTS_PER_REQUEST, although setting it will lead to unpredictable performance. In writing this patch, the question arrises as to if the additional cost of performing memcpys in the guest (to/from the pool of granted pages) outweigh the gains of not performing TLB shootdowns. The answer to that question is `no'. There appears to be very little, if any additional cost to the guest of using persistent grants. There is perhaps a small saving, from the reduced number of hypercalls performed in granting, and ending foreign access. Signed-off-by: Oliver Chick <oliver.chick@citrix.com> Signed-off-by: Roger Pau Monne <roger.pau@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v1: Fixed up the misuse of bool as int]
2012-10-30xen/blkback: Change xen_vbd's flush_support and discard_secure to have type ↵Oliver Chick
unsigned int, rather than bool Changing the type of bdev parameters to be unsigned int :1, rather than bool. This is more consistent with the types of other features in the block drivers. Signed-off-by: Oliver Chick <oliver.chick@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-10-30xen/blkback: use kmem_cache_zalloc instead of kmem_cache_alloc/memsetWei Yongjun
Using kmem_cache_zalloc() instead of kmem_cache_alloc() and memset(). spatch with a semantic match is used to found this problem. (http://coccinelle.lip6.fr/) Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30xen/blkback: Fix compile warningKonrad Rzeszutek Wilk
drivers/block/xen-blkback/xenbus.c:260:5: warning: symbol 'xenvbd_sysfs_addif' was not declared. Should it be static? drivers/block/xen-blkback/xenbus.c:284:6: warning: symbol 'xenvbd_sysfs_delif' was not declared. Should it be static? Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-07Merge tag 'stable/for-linus-3.7-arm-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull ADM Xen support from Konrad Rzeszutek Wilk: Features: * Allow a Linux guest to boot as initial domain and as normal guests on Xen on ARM (specifically ARMv7 with virtualized extensions). PV console, block and network frontend/backends are working. Bug-fixes: * Fix compile linux-next fallout. * Fix PVHVM bootup crashing. The Xen-unstable hypervisor (so will be 4.3 in a ~6 months), supports ARMv7 platforms. The goal in implementing this architecture is to exploit the hardware as much as possible. That means use as little as possible of PV operations (so no PV MMU) - and use existing PV drivers for I/Os (network, block, console, etc). This is similar to how PVHVM guests operate in X86 platform nowadays - except that on ARM there is no need for QEMU. The end result is that we share a lot of the generic Xen drivers and infrastructure. Details on how to compile/boot/etc are available at this Wiki: http://wiki.xen.org/wiki/Xen_ARMv7_with_Virtualization_Extensions and this blog has links to a technical discussion/presentations on the overall architecture: http://blog.xen.org/index.php/2012/09/21/xensummit-sessions-new-pvh-virtualisation-mode-for-arm-cortex-a15arm-servers-and-x86/ * tag 'stable/for-linus-3.7-arm-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (21 commits) xen/xen_initial_domain: check that xen_start_info is initialized xen: mark xen_init_IRQ __init xen/Makefile: fix dom-y build arm: introduce a DTS for Xen unprivileged virtual machines MAINTAINERS: add myself as Xen ARM maintainer xen/arm: compile netback xen/arm: compile blkfront and blkback xen/arm: implement alloc/free_xenballooned_pages with alloc_pages/kfree xen/arm: receive Xen events on ARM xen/arm: initialize grant_table on ARM xen/arm: get privilege status xen/arm: introduce CONFIG_XEN on ARM xen: do not compile manage, balloon, pci, acpi, pcpu and cpu_hotplug on ARM xen/arm: Introduce xen_ulong_t for unsigned long xen/arm: Xen detection and shared_info page mapping docs: Xen ARM DT bindings xen/arm: empty implementation of grant_table arch specific functions xen/arm: sync_bitops xen/arm: page.h definitions xen/arm: hypercalls ...
2012-09-12xen/m2p: do not reuse kmap_op->dev_bus_addrStefano Stabellini
If the caller passes a valid kmap_op to m2p_add_override, we use kmap_op->dev_bus_addr to store the original mfn, but dev_bus_addr is part of the interface with Xen and if we are batching the hypercalls it might not have been written by the hypervisor yet. That means that later on Xen will write to it and we'll think that the original mfn is actually what Xen has written to it. Rather than "stealing" struct members from kmap_op, keep using page->index to store the original mfn and add another parameter to m2p_remove_override to get the corresponding kmap_op instead. It is now responsibility of the caller to keep track of which kmap_op corresponds to a particular page in the m2p_override (gntdev, the only user of this interface that passes a valid kmap_op, is already doing that). CC: stable@kernel.org Reported-and-Tested-By: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-08xen/arm: compile blkfront and blkbackStefano Stabellini
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-06-13Merge branch 'stable/for-jens-3.5' of ↵Jens Axboe
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus
2012-05-30xen/blkback: Copy id field when doing BLKIF_DISCARD.Konrad Rzeszutek Wilk
We weren't copying the id field so when we sent the response back to the frontend (especially with a 64-bit host and 32-bit guest), we ended up using a random value. This lead to the frontend crashing as it would try to pass to __blk_end_request_all a NULL 'struct request' (b/c it would use the 'id' to find the proper 'struct request' in its shadow array) and end up crashing: BUG: unable to handle kernel NULL pointer dereference at 000000e4 IP: [<c0646d4c>] __blk_end_request_all+0xc/0x40 .. snip.. EIP is at __blk_end_request_all+0xc/0x40 .. snip.. [<ed95db72>] blkif_interrupt+0x172/0x330 [xen_blkfront] This fixes the bug by passing in the proper id for the response. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=824641 CC: stable@kernel.org Tested-by: William Dauchy <wdauchy@gmail.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-18xen/blkback: Fix warning error.Konrad Rzeszutek Wilk
drivers/block/xen-blkback/xenbus.c: In function 'xen_blkbk_discard': drivers/block/xen-blkback/xenbus.c:419:4: warning: passing argument 1 of 'dev_warn' makes pointer from integer without a cast +[enabled by default] include/linux/device.h:894:5: note: expected 'const struct device *' but argument is of type 'long int' It is unclear how that mistake made it in. It surely is wrong. Acked-by: Jens Axboe <axboe@kernel.dk> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-24xen/blkback: Make optional features be really optional.Konrad Rzeszutek Wilk
They were using the xenbus_dev_fatal() function which would change the state of the connection immediately. Which is not what we want when we advertise optional features. So make 'feature-discard','feature-barrier','feature-flush-cache' optional. Suggested-by: Jan Beulich <JBeulich@suse.com> [v1: Made the discard function void and static] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-24xen/blkback: Squash the discard support for 'file' and 'phy' type.Konrad Rzeszutek Wilk
The only reason for the distinction was for the special case of 'file' (which is assumed to be loopback device), was to reach inside the loopback device, find the underlaying file, and call fallocate on it. Fortunately "xen-blkback: convert hole punching to discard request on loop devices" removes that use-case and we now based the discard support based on blk_queue_discard(q) and extract all appropriate parameters from the 'struct request_queue'. CC: Li Dongyang <lidongyang@novell.com> Acked-by: Jan Beulich <JBeulich@suse.com> [v1: Dropping pointless initializer and keeping blank line] [v2: Remove the kfree as it is not used anymore] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-20xen/blkback: Enable blkback on HVM guestsDaniel De Graaf
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-20xen/blkback: use grant-table.c hypercall wrappersDaniel De Graaf
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-15Merge branch 'for-3.3/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
* 'for-3.3/drivers' of git://git.kernel.dk/linux-block: mtip32xx: do rebuild monitoring asynchronously xen-blkfront: Use kcalloc instead of kzalloc to allocate array mtip32xx: uninitialized variable in mtip_quiesce_io() mtip32xx: updates based on feedback xen-blkback: convert hole punching to discard request on loop devices xen/blkback: Move processing of BLKIF_OP_DISCARD from dispatch_rw_block_io xen/blk[front|back]: Enhance discard support with secure erasing support. xen/blk[front|back]: Squash blkif_request_rw and blkif_request_discard together mtip32xx: update to new ->make_request() API mtip32xx: add module.h include to avoid conflict with moduleh tree mtip32xx: mark a few more items static mtip32xx: ensure that all local functions are static mtip32xx: cleanup compat ioctl handling mtip32xx: fix warnings/errors on 32-bit compiles block: Add driver for Micron RealSSD pcie flash cards
2012-01-10Merge branch 'stable/for-linus-3.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/for-linus-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (37 commits) xen/pciback: Expand the warning message to include domain id. xen/pciback: Fix "device has been assigned to X domain!" warning xen/pciback: Move the PCI_DEV_FLAGS_ASSIGNED ops to the "[un|]bind" xen/xenbus: don't reimplement kvasprintf via a fixed size buffer xenbus: maximum buffer size is XENSTORE_PAYLOAD_MAX xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX. Xen: consolidate and simplify struct xenbus_driver instantiation xen-gntalloc: introduce missing kfree xen/xenbus: Fix compile error - missing header for xen_initial_domain() xen/netback: Enable netback on HVM guests xen/grant-table: Support mappings required by blkback xenbus: Use grant-table wrapper functions xenbus: Support HVM backends xen/xenbus-frontend: Fix compile error with randconfig xen/xenbus-frontend: Make error message more clear xen/privcmd: Remove unused support for arch specific privcmp mmap xen: Add xenbus_backend device xen: Add xenbus device driver xen: Add privcmd device driver xen/gntalloc: fix reference counts on multi-page mappings ...
2012-01-04Xen: consolidate and simplify struct xenbus_driver instantiationJan Beulich
The 'name', 'owner', and 'mod_name' members are redundant with the identically named fields in the 'driver' sub-structure. Rather than switching each instance to specify these fields explicitly, introduce a macro to simplify this. Eliminate further redundancy by allowing the drvname argument to DEFINE_XENBUS_DRIVER() to be blank (in which case the first entry from the ID table will be used for .driver.name). Also eliminate the questionable xenbus_register_{back,front}end() wrappers - their sole remaining purpose was the checking of the 'owner' field, proper setting of which shouldn't be an issue anymore when the macro gets used. v2: Restore DRV_NAME for the driver name in xen-pciback. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-12-02treewide: Fix typos in various parts of the kernel, and fix some comments.Justin P. Mattock
The below patch fixes some typos in various parts of the kernel, as well as fixes some comments. Please let me know if I missed anything, and I will try to get it changed and resent. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-11-18xen-blkback: convert hole punching to discard request on loop devicesLi Dongyang
As of dfaa2ef68e80c378e610e3c8c536f1c239e8d3ef, loop devices support discard request now. We could just issue a discard request, and the loop driver will punch the hole for us, so we don't need to touch the internals of loop device and punch the hole ourselves, Thanks. V0->V1: rebased on devel/for-jens-3.3 Signed-off-by: Li Dongyang <lidongyang@novell.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-18xen/blkback: Move processing of BLKIF_OP_DISCARD from dispatch_rw_block_ioKonrad Rzeszutek Wilk
.. and move it to its own function that will deal with the discard operation. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-18xen/blk[front|back]: Enhance discard support with secure erasing support.Konrad Rzeszutek Wilk
Part of the blkdev_issue_discard(xx) operation is that it can also issue a secure discard operation that will permanantly remove the sectors in question. We advertise that we can support that via the 'discard-secure' attribute and on the request, if the 'secure' bit is set, we will attempt to pass in REQ_DISCARD | REQ_SECURE. CC: Li Dongyang <lidongyang@novell.com> [v1: Used 'flag' instead of 'secure:1' bit] [v2: Use 'reserved' uint8_t instead of adding a new value] [v3: Check for nseg when mapping instead of operation] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-18xen/blk[front|back]: Squash blkif_request_rw and blkif_request_discard togetherKonrad Rzeszutek Wilk
In a union type structure to deal with the overlapping attributes in a easier manner. Suggested-by: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-06Merge branch 'stable/vmalloc-3.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: net: xen-netback: use API provided by xenbus module to map rings block: xen-blkback: use API provided by xenbus module to map rings xen: use generic functions instead of xen_{alloc, free}_vm_area()
2011-11-04Merge branch 'for-3.2/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
* 'for-3.2/drivers' of git://git.kernel.dk/linux-block: (30 commits) virtio-blk: use ida to allocate disk index hpsa: add small delay when using PCI Power Management to reset for kump cciss: add small delay when using PCI Power Management to reset for kump xen/blkback: Fix two races in the handling of barrier requests. xen/blkback: Check for proper operation. xen/blkback: Fix the inhibition to map pages when discarding sector ranges. xen/blkback: Report VBD_WSECT (wr_sect) properly. xen/blkback: Support 'feature-barrier' aka old-style BARRIER requests. xen-blkfront: plug device number leak in xlblk_init() error path xen-blkfront: If no barrier or flush is supported, use invalid operation. xen-blkback: use kzalloc() in favor of kmalloc()+memset() xen-blkback: fixed indentation and comments xen-blkfront: fix a deadlock while handling discard response xen-blkfront: Handle discard requests. xen-blkback: Implement discard requests ('feature-discard') xen-blkfront: add BLKIF_OP_DISCARD and discard request struct drivers/block/loop.c: remove unnecessary bdev argument from loop_clr_fd() drivers/block/loop.c: emit uevent on auto release drivers/block/cpqarray.c: use pci_dev->revision loop: always allow userspace partitions and optionally support automatic scanning ... Fic up trivial header file includsion conflict in drivers/block/loop.c
2011-10-26block: xen-blkback: use API provided by xenbus module to map ringsDavid Vrabel
The xenbus module provides xenbus_map_ring_valloc() and xenbus_map_ring_vfree(). Use these to map the ring pages granted by the frontend. Acked-by: Jens Axboe <jaxboe@fusionio.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-25Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (59 commits) MAINTAINERS: linux-m32r is moderated for non-subscribers linux@lists.openrisc.net is moderated for non-subscribers Drop default from "DM365 codec select" choice parisc: Kconfig: cleanup Kernel page size default Kconfig: remove redundant CONFIG_ prefix on two symbols cris: remove arch/cris/arch-v32/lib/nand_init.S microblaze: add missing CONFIG_ prefixes h8300: drop puzzling Kconfig dependencies MAINTAINERS: microblaze-uclinux@itee.uq.edu.au is moderated for non-subscribers tty: drop superfluous dependency in Kconfig ARM: mxc: fix Kconfig typo 'i.MX51' Fix file references in Kconfig files aic7xxx: fix Kconfig references to READMEs Fix file references in drivers/ide/ thinkpad_acpi: Fix printk typo 'bluestooth' bcmring: drop commented out line in Kconfig btmrvl_sdio: fix typo 'btmrvl_sdio_sd6888' doc: raw1394: Trivial typo fix CIFS: Don't free volume_info->UNC until we are entirely done with it. treewide: Correct spelling of successfully in comments ...
2011-10-25Merge branches 'stable/bug.fixes-3.2' and 'stable/mmu.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/bug.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/p2m/debugfs: Make type_name more obvious. xen/p2m/debugfs: Fix potential pointer exception. xen/enlighten: Fix compile warnings and set cx to known value. xen/xenbus: Remove the unnecessary check. xen/irq: If we fail during msi_capability_init return proper error code. xen/events: Don't check the info for NULL as it is already done. xen/events: BUG() when we can't allocate our event->irq array. * 'stable/mmu.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: Fix selfballooning and ensure it doesn't go too far xen/gntdev: Fix sleep-inside-spinlock xen: modify kernel mappings corresponding to granted pages xen: add an "highmem" parameter to alloc_xenballooned_pages xen/p2m: Use SetPagePrivate and its friends for M2P overrides. xen/p2m: Make debug/xen/mmu/p2m visible again. Revert "xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set."
2011-10-17xen/blkback: Fix two races in the handling of barrier requests.Konrad Rzeszutek Wilk
There are two windows of opportunity to cause a race when processing a barrier request. This patch fixes this. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-14xen/blkback: Check for proper operation.Konrad Rzeszutek Wilk
The patch titled: "xen/blkback: Fix the inhibition to map pages when discarding sector ranges." had the right idea except that it used the wrong comparison operator. It had == instead of !=. This fixes the bug where all (except discard) operations would have been ignored. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen/blkback: Fix the inhibition to map pages when discarding sector ranges.Konrad Rzeszutek Wilk
The 'operation' parameters are the ones provided to the bio layer while the req->operation are the ones passed in between the backend and frontend. We used the wrong 'operation' value to squash the call to map pages when processing the discard operation resulting in an hypercall that did nothing. Lets guard against going in the mapping function by checking for the proper operation type. CC: Li Dongyang <lidongyang@novell.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen/blkback: Report VBD_WSECT (wr_sect) properly.Konrad Rzeszutek Wilk
We did not increment the amount of sectors written to disk b/c we tested for the == WRITE which is incorrect - as the operations are more of WRITE_FLUSH, WRITE_ODIRECT. This patch fixes it by doing a & WRITE check. CC: stable@kernel.org Reported-by: Andy Burns <xen.lists@burns.me.uk> Suggested-by: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen/blkback: Support 'feature-barrier' aka old-style BARRIER requests.Konrad Rzeszutek Wilk
We emulate the barrier requests by draining the outstanding bio's and then sending the WRITE_FLUSH command. To drain the I/Os we use the refcnt that is used during disconnect to wait for all the I/Os before disconnecting from the frontend. We latch on its value and if it reaches either the threshold for disconnect or when there are no more outstanding I/Os, then we have drained all I/Os. Suggested-by: Christopher Hellwig <hch@infradead.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen-blkback: use kzalloc() in favor of kmalloc()+memset()Jan Beulich
This fixes the problem of three of those four memset()-s having improper size arguments passed: Sizeof a pointer-typed expression returns the size of the pointer, not that of the pointed to data. It also reverts using kmalloc() instead of kzalloc() for the allocation of the pending grant handles array, as that array gets fully initialized in a subsequent loop. Reported-by: Julia Lawall <julia@diku.dk> Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen-blkback: fixed indentation and commentsJoe Jin
This patch fixes belows: 1. Fix code style issue. 2. Fix incorrect functions name in comments. Signed-off-by: Joe Jin <joe.jin@oracle.com> Cc: Jens Axboe <jaxboe@fusionio.com> Cc: Ian Campbell <Ian.Campbell@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen-blkback: Implement discard requests ('feature-discard')Li Dongyang
..aka ATA TRIM/SCSI UNMAP command to be passed through the frontend and used as appropiately by the backend. We also advertise certain granulity parameters to the frontend so it can plug them in. If the backend is a realy device - we just end up using 'blkdev_issue_discard' while for loopback devices - we just punch a hole in the image file. Signed-off-by: Li Dongyang <lidongyang@novell.com> [v1: Fixed up pr_debug and commit description] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-29xen: modify kernel mappings corresponding to granted pagesStefano Stabellini
If we want to use granted pages for AIO, changing the mappings of a user vma and the corresponding p2m is not enough, we also need to update the kernel mappings accordingly. Currently this is only needed for pages that are created for user usages through /dev/xen/gntdev. As in, pages that have been in use by the kernel and use the P2M will not need this special mapping. However there are no guarantees that in the future the kernel won't start accessing pages through the 1:1 even for internal usage. In order to avoid the complexity of dealing with highmem, we allocated the pages lowmem. We issue a HYPERVISOR_grant_table_op right away in m2p_add_override and we remove the mappings using another HYPERVISOR_grant_table_op in m2p_remove_override. Considering that m2p_add_override and m2p_remove_override are called once per page we use multicalls and hypercall batching. Use the kmap_op pointer directly as argument to do the mapping as it is guaranteed to be present up until the unmapping is done. Before issuing any unmapping multicalls, we need to make sure that the mapping has already being done, because we need the kmap->handle to be set correctly. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> [v1: Removed GRANT_FRAME_BIT usage] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>