aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/block/xen-blkback/xenbus.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2014-02-11xen-blkback: init persistent_purge_work work_structRoger Pau Monne1-0/+1
Initialize persistent_purge_work work_struct on xen_blkif_alloc (and remove the previous initialization done in purge_persistent_gnt). This prevents flush_work from complaining even if purge_persistent_gnt has not been used. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-02-07xen-blkback: fix shutdown raceRoger Pau Monne1-0/+1
Introduce a new variable to keep track of the number of in-flight requests. We need to make sure that when xen_blkif_put is called the request has already been freed and we can safely free xen_blkif, which was not the case before. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Tested-by: Matt Rushton <mrushton@amazon.com> Reviewed-by: Matt Rushton <mrushton@amazon.com> Cc: Matt Wilson <msw@amazon.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-02-07xen-blkback: fix memory leaksRoger Pau Monne1-0/+12
I've at least identified two possible memory leaks in blkback, both related to the shutdown path of a VBD: - blkback doesn't wait for any pending purge work to finish before cleaning the list of free_pages. The purge work will call put_free_pages and thus we might end up with pages being added to the free_pages list after we have emptied it. Fix this by making sure there's no pending purge work before exiting xen_blkif_schedule, and moving the free_page cleanup code to xen_blkif_free. - blkback doesn't wait for pending requests to end before cleaning persistent grants and the list of free_pages. Again this can add pages to the free_pages list or persistent grants to the persistent_gnts red-black tree. Fixed by moving the persistent grants and free_pages cleanup code to xen_blkif_free. Also, add some checks in xen_blkif_free to make sure we are cleaning everything. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Tested-by: Matt Rushton <mrushton@amazon.com> Reviewed-by: Matt Rushton <mrushton@amazon.com> Cc: Matt Wilson <msw@amazon.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-09-11block: replace strict_strtoul() with kstrtoul()Jingoo Han1-1/+1
The use of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-22Merge branch 'for-3.11/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+85
Pull block IO driver bits from Jens Axboe: "As I mentioned in the core block pull request, due to real life circumstances the driver pull request would be late. Now it looks like -rc2 late... On the plus side, apart form the rsxx update, these are all things that I could argue could go in later in the cycle as they are fixes and not features. So even though things are late, it's not ALL bad. The pull request contains: - Updates to bcache, all bug fixes, from Kent. - A pile of drbd bug fixes (no big features this time!). - xen blk front/back fixes. - rsxx driver updates, some of them deferred form 3.10. So should be well cooked by now" * 'for-3.11/drivers' of git://git.kernel.dk/linux-block: (63 commits) bcache: Allocation kthread fixes bcache: Fix GC_SECTORS_USED() calculation bcache: Journal replay fix bcache: Shutdown fix bcache: Fix a sysfs splat on shutdown bcache: Advertise that flushes are supported bcache: check for allocation failures bcache: Fix a dumb race bcache: Use standard utility code bcache: Update email address bcache: Delete fuzz tester bcache: Document shrinker reserve better bcache: FUA fixes drbd: Allow online change of al-stripes and al-stripe-size drbd: Constants should be UPPERCASE drbd: Ignore the exit code of a fence-peer handler if it returns too late drbd: Fix rcu_read_lock balance on error path drbd: fix error return code in drbd_init() drbd: Do not sleep inside rcu bcache: Refresh usage docs ...
2013-07-03drivers: avoid parsing names as kthread_run() format stringsKees Cook1-1/+1
Calling kthread_run with a single name parameter causes it to be handled as a format string. Many callers are passing potentially dynamic string content, so use "%s" in those cases to avoid any potential accidents. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-06-17xen/blkback: Check for insane amounts of request on the ring (v6).Konrad Rzeszutek Wilk1-0/+2
Check that the ring does not have an insane amount of requests (more than there could fit on the ring). If we detect this case we will stop processing the requests and wait until the XenBus disconnects the ring. The existing check RING_REQUEST_CONS_OVERFLOW which checks for how many responses we have created in the past (rsp_prod_pvt) vs requests consumed (req_cons) and whether said difference is greater or equal to the size of the ring, does not catch this case. Wha the condition does check if there is a need to process more as we still have a backlog of responses to finish. Note that both of those values (rsp_prod_pvt and req_cons) are not exposed on the shared ring. To understand this problem a mini crash course in ring protocol response/request updates is in place. There are four entries: req_prod and rsp_prod; req_event and rsp_event to track the ring entries. We are only concerned about the first two - which set the tone of this bug. The req_prod is a value incremented by frontend for each request put on the ring. Conversely the rsp_prod is a value incremented by the backend for each response put on the ring (rsp_prod gets set by rsp_prod_pvt when pushing the responses on the ring). Both values can wrap and are modulo the size of the ring (in block case that is 32). Please see RING_GET_REQUEST and RING_GET_RESPONSE for the more details. The culprit here is that if the difference between the req_prod and req_cons is greater than the ring size we have a problem. Fortunately for us, the '__do_block_io_op' loop: rc = blk_rings->common.req_cons; rp = blk_rings->common.sring->req_prod; while (rc != rp) { .. blk_rings->common.req_cons = ++rc; /* before make_response() */ } will loop up to the point when rc == rp. The macros inside of the loop (RING_GET_REQUEST) is smart and is indexing based on the modulo of the ring size. If the frontend has provided a bogus req_prod value we will loop until the 'rc == rp' - which means we could be processing already processed requests (or responses) often. The reason the RING_REQUEST_CONS_OVERFLOW is not helping here is b/c it only tracks how many responses we have internally produced and whether we would should process more. The astute reader will notice that the macro RING_REQUEST_CONS_OVERFLOW provides two arguments - more on this later. For example, if we were to enter this function with these values: blk_rings->common.sring->req_prod = X+31415 (X is the value from the last time __do_block_io_op was called). blk_rings->common.req_cons = X blk_rings->common.rsp_prod_pvt = X The RING_REQUEST_CONS_OVERFLOW(&blk_rings->common, blk_rings->common.req_cons) is doing: req_cons - rsp_prod_pvt >= 32 Which is, X - X >= 32 or 0 >= 32 And that is false, so we continue on looping (this bug). If we re-use said macro RING_REQUEST_CONS_OVERFLOW and pass in the rp instead (sring->req_prod) of rc, the this macro can do the check: req_prod - rsp_prov_pvt >= 32 Which is, X + 31415 - X >= 32 , or 31415 >= 32 which is true, so we can error out and break out of the function. Unfortunatly the difference between rsp_prov_pvt and req_prod can be at 32 (which would error out in the macro). This condition exists when the backend is lagging behind with the responses and still has not finished responding to all of them (so make_response has not been called), and the rsp_prov_pvt + 32 == req_cons. This ends up with us not being able to use said macro. Hence introducing a new macro called RING_REQUEST_PROD_OVERFLOW which does a simple check of: req_prod - rsp_prod_pvt > RING_SIZE And with the X values from above: X + 31415 - X > 32 Returns true. Also not that if the ring is full (which is where the RING_REQUEST_CONS_OVERFLOW triggered), we would not hit the same condition: X + 32 - X > 32 Which is false. Lets use that macro. Note that in v5 of this patchset the macro was different - we used an earlier version. Cc: stable@vger.kernel.org [v1: Move the check outside the loop] [v2: Add a pr_warn as suggested by David] [v3: Use RING_REQUEST_CONS_OVERFLOW as suggested by Jan] [v4: Move wake_up after kthread_stop as suggested by Jan] [v5: Use RING_REQUEST_PROD_OVERFLOW instead] [v6: Use RING_REQUEST_PROD_OVERFLOW - Jan's version] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> gadsa
2013-06-07xen/blkback: Use physical sector size for setupStefan Bader1-0/+5
Currently xen-blkback passes the logical sector size over xenbus and xen-blkfront sets up the paravirt disk with that logical block size. But newer drives usually have the logical sector size set to 512 for compatibility reasons and would show the actual sector size only in physical sector size. This results in the device being partitioned and accessed in dom0 with the correct sector size, but the guest thinks 512 bytes is the correct block size. And that results in poor performance. To fix this, blkback gets modified to pass also physical-sector-size over xenbus and blkfront to use both values to set up the paravirt disk. I did not just change the passed in sector-size because I am not sure having a bigger logical sector size than the physical one is valid (and that would happen if a newer dom0 kernel hits an older domU kernel). Also this way a domU set up before should still be accessible (just some tools might detect the unaligned setup). [v2: Make xenbus write failure non-fatal] [v3: Use xenbus_scanf instead of xenbus_gather] [v4: Rebased against segment changes] Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-07xen-blkback: allocate list of pending reqs in small chunksRoger Pau Monne1-17/+57
Allocate pending requests in smaller chunks instead of allocating them all at the same time. This change also removes the global array of pending_reqs, it is no longer necessay. Variables related to the grant mapping have been grouped into a struct called "grant_page", this allows to allocate them in smaller chunks, and also improves memory locality. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-18xen-block: implement indirect descriptorsRoger Pau Monne1-0/+7
Indirect descriptors introduce a new block operation (BLKIF_OP_INDIRECT) that passes grant references instead of segments in the request. This grant references are filled with arrays of blkif_request_segment_aligned, this way we can send more segments in a request. The proposed implementation sets the maximum number of indirect grefs (frames filled with blkif_request_segment_aligned) to 256 in the backend and 32 in the frontend. The value in the frontend has been chosen experimentally, and the backend value has been set to a sane value that allows expanding the maximum number of indirect descriptors in the frontend if needed. The migration code has changed from the previous implementation, in which we simply remapped the segments on the shared ring. Now the maximum number of segments allowed in a request can change depending on the backend, so we have to requeue all the requests in the ring and in the queue and split the bios in them if they are bigger than the new maximum number of segments. [v2: Fixed minor comments by Konrad. [v1: Added padding to make the indirect request 64bit aligned. Added some BUGs, comments; fixed number of indirect pages in blkif_get_x86_{32/64}_req. Added description about the indirect operation in blkif.h] Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> [v3: Fixed spaces and tabs mix ups] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-18xen-blkback: make the queue of free requests per backendRoger Pau Monne1-0/+26
Remove the last dependency from blkbk by moving the list of free requests to blkif. This change reduces the contention on the list of available requests. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: xen-devel@lists.xen.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-18xen-blkback: implement LRU mechanism for persistent grantsRoger Pau Monne1-0/+2
This mechanism allows blkback to change the number of grants persistently mapped at run time. The algorithm uses a simple LRU mechanism that removes (if needed) the persistent grants that have not been used since the last LRU run, or if all grants have been used it removes the first grants in the list (that are not in use). The algorithm allows the user to change the maximum number of persistent grants, by changing max_persistent_grants in sysfs. Since we are storing the persistent grants used inside the request struct (to be able to mark them as "unused" when unmapping), we no longer need the bitmap (unmap_seg). Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: xen-devel@lists.xen.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-04-18xen-blkback: use balloon pages for all mappingsRoger Pau Monne1-0/+3
Using balloon pages for all granted pages allows us to simplify the logic in blkback, especially in the xen_blkbk_map function, since now we can decide if we want to map a grant persistently or not after we have actually mapped it. This could not be done before because persistent grants used ballooned pages, whereas non-persistent grants used pages from the kernel. This patch also introduces several changes, the first one is that the list of free pages is no longer global, now each blkback instance has it's own list of free pages that can be used to map grants. Also, a run time parameter (max_buffer_pages) has been added in order to tune the maximum number of free pages each blkback instance will keep in it's buffer. 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>
2013-03-11xen/blkback: Change statistics counter types to unsignedZoltan Kiss1-7/+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>
2013-02-19xen-blkback: do not leak mode propertyJan Beulich1-25/+24
"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>
2012-12-17Merge branch 'for-3.8/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-2/+21
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 ...
2012-11-04xen/blkback: persistent-grants fixesRoger Pau Monne1-1/+1
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 Monne1-2/+21
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: use kmem_cache_zalloc instead of kmem_cache_alloc/memsetWei Yongjun1-2/+1
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 Wilk1-3/+3
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>
2012-04-18xen/blkback: Fix warning error.Konrad Rzeszutek Wilk1-1/+1
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 Wilk1-21/+14
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 Wilk1-44/+26
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>
2012-01-15Merge branch 'for-3.3/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+12
* '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 git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xenLinus Torvalds1-6/+3
* '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 Beulich1-6/+3
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. Mattock1-1/+1
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/blk[front|back]: Enhance discard support with secure erasing support.Konrad Rzeszutek Wilk1-0/+12
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>
2011-11-06Merge branch 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xenLinus Torvalds1-47/+7
* '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 Torvalds1-0/+76
* '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 Vrabel1-47/+7
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>
2011-10-13xen/blkback: Support 'feature-barrier' aka old-style BARRIER requests.Konrad Rzeszutek Wilk1-0/+18
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: fixed indentation and commentsJoe Jin1-2/+2
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 Dongyang1-0/+58
..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>
2011-08-23Merge branch 'stable/for-jens' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linusJens Axboe1-3/+3
2011-08-22xen-blkback: fixed indentation and commentsJoe Jin1-2/+2
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>
2011-08-22xen-blkback: Don't disconnect backend until state switched to XenbusStateClosed.Joe Jin1-1/+1
When do block-attach/block-detach test with below steps, umount hangs in the guest. Furthermore shutdown ends up being stuck when umounting file-systems. 1. start guest. 2. attach new block device by xm block-attach in Dom0. 3. mount new disk in guest. 4. execute xm block-detach to detach the block device in dom0 until timeout 5. Any request to the disk will hung. Root cause: This issue is caused when setting backend device's state to 'XenbusStateClosing', which sends to the frontend the XenbusStateClosing notification. When frontend receives the notification it tries to release the disk in blkfront_closing(), but at that moment the disk is still in use by guest, so frontend refuses to close. Specifically it sets the disk state to XenbusStateClosing and sends the notification to backend - when backend receives the event, it disconnects the vbd from real device, and sets the vbd device state to XenbusStateClosing. The backend disconnects the real device/file, and any IO requests to the disk in guest will end up in ether, leaving disk DEAD and set to XenbusStateClosing. When the guest wants to disconnect the disk, umount will hang on blkif_release()->xlvbd_release_gendisk() as it is unable to send any IO to the disk, which prevents clean system shutdown. Solution: Don't disconnect backend until frontend state switched to XenbusStateClosed. Signed-off-by: Joe Jin <joe.jin@oracle.com> Cc: Daniel Stodden <daniel.stodden@citrix.com> Cc: Jens Axboe <jaxboe@fusionio.com> Cc: Annie Li <annie.li@oracle.com> Cc: Ian Campbell <Ian.Campbell@eu.citrix.com> [v1: Modified description a bit] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-06-30xen: Add __attribute__((format(printf... where appropriateJoe Perches1-1/+1
Use the compiler to verify printf formats and arguments. Fix fallout. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-06-01xen/blkback: don't call vbd_size() if bd_disk is NULLLaszlo Ersek1-2/+1
...because vbd_size() dereferences bd_disk if bd_part is NULL. Signed-off-by: Laszlo Ersek<lersek@redhat.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Align the tabs on the structure.Konrad Rzeszutek Wilk1-1/+1
The recent changes caused this field of the structure to be offset a bit. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Prefix 'vbd' with 'xen' in structs and functions.Konrad Rzeszutek Wilk1-17/+17
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Change structure name blkif_st to xen_blkif.Konrad Rzeszutek Wilk1-12/+12
No need for that '_st' and xen_blkif is more apt. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Checkpatch.pl recommend against multiple assigments.Konrad Rzeszutek Wilk1-2/+4
CHECK: multiple assignments should be avoided Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Fix spelling mistakes.Konrad Rzeszutek Wilk1-2/+2
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Use the DRV_PFX in the pr_.. macros.Konrad Rzeszutek Wilk1-3/+3
To make it easier to read. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Make the DPRINTK uniform.Konrad Rzeszutek Wilk1-5/+0
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen/blkback: Change printk/DPRINTK to pr_.. type variant.Konrad Rzeszutek Wilk1-11/+8
And also make them uniform and prefix the message with 'xen-blkback'. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-11xen/blkback: Fixed up comments and converted spaces to tabs.Konrad Rzeszutek Wilk1-17/+22
Suggested-by: Ian Campbell <Ian.Campbell@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-05xen/blkback: Add support for BLKIF_OP_FLUSH_DISKCACHE and drop BLKIF_OP_WRITE_BARRIER.Konrad Rzeszutek Wilk1-7/+12
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>
2011-04-20xen/blkback: Prefix exposed functions with xen_Konrad Rzeszutek Wilk1-39/+41
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>