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path: root/drivers/block/xen-blkback/common.h
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* xen-blkback: don't store dev_bus_addrRoger Pau Monne2013-03-191-1/+0
| | | | | | | | | | | | | | | | | | | | 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>
* xen/blkback: Change statistics counter types to unsignedZoltan Kiss2013-03-111-7/+7
| | | | | | | | | | 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>
* xen/blkback: correctly respond to unknown, non-native requestsDavid Vrabel2013-03-111-0/+25
| | | | | | | | | | | | | | | | | | | | | 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>
* Merge branch 'for-3.8/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds2012-12-171-0/+16
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * xen/blkback: Persistent grant maps for xen blk driversRoger Pau Monne2012-10-301-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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]
* | xen/blkback: Change xen_vbd's flush_support and discard_secure to have type ↵Oliver Chick2012-10-301-2/+2
|/ | | | | | | | | | | 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>
* xen/blkback: Copy id field when doing BLKIF_DISCARD.Konrad Rzeszutek Wilk2012-05-301-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* xen/blkback: Squash the discard support for 'file' and 'phy' type.Konrad Rzeszutek Wilk2012-03-241-6/+0
| | | | | | | | | | | | | | | | 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>
* xen/blk[front|back]: Enhance discard support with secure erasing support.Konrad Rzeszutek Wilk2011-11-181-2/+5
| | | | | | | | | | | | | | 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>
* xen/blk[front|back]: Squash blkif_request_rw and blkif_request_discard togetherKonrad Rzeszutek Wilk2011-11-181-28/+36
| | | | | | | | 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>
* Merge branch 'stable/vmalloc-3.2' of ↵Linus Torvalds2011-11-061-4/+1
|\ | | | | | | | | | | | | | | | | 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()
| * block: xen-blkback: use API provided by xenbus module to map ringsDavid Vrabel2011-10-261-4/+1
| | | | | | | | | | | | | | | | | | | | 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>
* | Merge branch 'for-3.2/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds2011-11-041-17/+81
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * '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
| * | xen/blkback: Support 'feature-barrier' aka old-style BARRIER requests.Konrad Rzeszutek Wilk2011-10-131-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | xen-blkback: fixed indentation and commentsJoe Jin2011-10-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | xen-blkback: Implement discard requests ('feature-discard')Li Dongyang2011-10-131-17/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ..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>
* | | Merge branch 'for-linus' of ↵Linus Torvalds2011-10-251-1/+0
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * | Remove unneeded version.h includes from drivers/block/Jesper Juhl2011-09-151-1/+0
| |/ | | | | | | | | | | | | | | | | It was pointed out by 'make versioncheck' that some includes of linux/version.h are not needed in drivers/block/. This patch removes them. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* / xen-blkback: fixed indentation and commentsJoe Jin2011-08-221-1/+1
|/ | | | | | | | | | | | 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>
* xen/blkback: Add the prefix XEN in the common.h.Konrad Rzeszutek Wilk2011-05-121-3/+3
| | | | Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Prefix 'vbd' with 'xen' in structs and functions.Konrad Rzeszutek Wilk2011-05-121-2/+2
| | | | Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Change structure name blkif_st to xen_blkif.Konrad Rzeszutek Wilk2011-05-121-1/+1
| | | | | | No need for that '_st' and xen_blkif is more apt. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Remove the unused typedefs.Konrad Rzeszutek Wilk2011-05-121-4/+0
| | | | Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Move include/xen/blkif.h into drivers/block/xen-blkback/common.hKonrad Rzeszutek Wilk2011-05-121-1/+71
| | | | | Not point of the blkif.h file. It is not used by the frontend. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Fixing some more of the cleanpatch.pl warnings.Konrad Rzeszutek Wilk2011-05-121-2/+2
| | | | Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Move blkif_get_x86_[32|64]_req to common.h in block/xen-blkback ↵Konrad Rzeszutek Wilk2011-05-121-0/+32
| | | | | | | | dir. From the blkif.h header, which was exposed to the frontend. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Use the DRV_PFX in the pr_.. macros.Konrad Rzeszutek Wilk2011-05-121-1/+2
| | | | | To make it easier to read. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Make the DPRINTK uniform.Konrad Rzeszutek Wilk2011-05-121-3/+3
| | | | Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Fixed up comments and converted spaces to tabs.Konrad Rzeszutek Wilk2011-05-111-36/+41
| | | | | Suggested-by: Ian Campbell <Ian.Campbell@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Add support for BLKIF_OP_FLUSH_DISKCACHE and drop ↵Konrad Rzeszutek Wilk2011-05-051-3/+4
| | | | | | | | | | BLKIF_OP_WRITE_BARRIER. We drop the support for 'feature-barrier' and add in the support for the 'feature-flush-cache' if the real backend storage supports flushing. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Prefix exposed functions with xen_Konrad Rzeszutek Wilk2011-04-201-9/+9
| | | | | | | | | And also shorten the name if it has blkback to blkbk. This results in the symbol table (if compiled in the kernel) to be much shorter, prettier, and also easier to search for. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen-blkback: Inline some of the functions that were moved from vbd/interface.cKonrad Rzeszutek Wilk2011-04-201-18/+4
| | | | | | Shuffling code around. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/blkback: Move it from drivers/xen to drivers/blockKonrad Rzeszutek Wilk2011-04-181-0/+142
.. and modify the Makefile and Kconfig files appropriately. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>