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2013-06-28Merge branch 'stable/for-jens-3.10' of ↵Jens Axboe1-100/+432
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-3.11/drivers Konrad writes: It has the 'feature-max-indirect-segments' implemented in both backend and frontend. The current problem with the backend and frontend is that the segment size is limited to 11 pages. It means we can at most squeeze in 44kB per request. The ring can hold 32 (next power of two below 36) requests, meaning we can do 1.4M of outstanding requests. Nowadays that is not enough. The problem in the past was addressed in two ways - but neither one went upstream. The first solution to this proposed by Justin from Spectralogic was to negotiate the segment size. This means that the ‘struct blkif_sring_entry’ is now a variable size. It can expand from 112 bytes (cover 11 pages of data - 44kB) to 1580 bytes (256 pages of data - so 1MB). It is a simple extension by just making the array in the request expand from 11 to a variable size negotiated. But it had limits: this extension still limits the number of segments per request to 255 (as the total number must be specified in the request, which only has an 8-bit field for that purpose). The other solution (from Intel - Ronghui) was to create one extra ring that only has the ‘struct blkif_request_segment’ in them. The ‘struct blkif_request’ would be changed to have an index in said ‘segment ring’. There is only one segment ring. This means that the size of the initial ring is still the same. The requests would point to the segment and enumerate out how many of the indexes it wants to use. The limit is of course the size of the segment. If one assumes a one-page segment this means we can in one request cover ~4MB. Those patches were posted as RFC and the author never followed up on the ideas on changing it to be a bit more flexible. There is yet another mechanism that could be employed  (which these patches implement) - and it borrows from VirtIO protocol. And that is the ‘indirect descriptors’. This very similar to what Intel suggests, but with a twist. The twist is to negotiate how many of these 'segment' pages (aka indirect descriptor pages) we want to support (in reality we negotiate how many entries in the segment we want to cover, and we module the number if it is bigger than the segment size). This means that with the existing 36 slots in the ring (single page) we can cover: 32 slots * each blkif_request_indirect covers: 512 * 4096 ~= 64M. Since we ample space in the blkif_request_indirect to span more than one indirect page, that number (64M) can be also multiplied by eight = 512MB. Roger Pau Monne took the idea and implemented them in these patches. They work great and the corner cases (migration between backends with and without this extension) work nicely. The backend has a limit right now off how many indirect entries it can handle: one indirect page, and at maximum 256 entries (out of 512 - so 50% of the page is used). That comes out to 32 slots * 256 entries in a indirect page * 1 indirect page per request * 4096 = 32MB. This is a conservative number that can change in the future. Right now it strikes a good balance between giving excellent performance, memory usage in the backend, and balancing the needs of many guests. In the patchset there is also the split of the blkback structure to be per-VBD. This means that the spinlock contention we had with many guests trying to do I/O and all the blkback threads hitting the same lock has been eliminated. Also there are bug-fixes to deal with oddly sized sectors, insane amounts on th ring, and also a security fix (posted earlier).
2013-06-21xen-blkfront: set blk_queue_max_hw_sectors correctlyRoger Pau Monne1-1/+1
Now that indirect segments are enabled blk_queue_max_hw_sectors must be set to match the maximum number of sectors we can handle in a request. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reported-by: Felipe Franciosi <felipe.franciosi@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-08xen/blkback: Use physical sector size for setupStefan Bader1-3/+18
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>
2013-06-04xen-blkfront: Introduce a 'max' module parameter to alter the amount of ↵Konrad Rzeszutek Wilk1-0/+2
indirect segments. The max module parameter (by default 32) is the maximum number of segments that the frontend will negotiate with the backend for indirect descriptors. Higher value means more potential throughput but more memory usage. The backend picks the minimum of the frontend and its default backend value. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-08xen-blkfront: use a different scatterlist for each requestRoger Pau Monne1-25/+18
In blkif_queue_request blkfront iterates over the scatterlist in order to set the segments of the request, and in blkif_completion blkfront iterates over the raw request, which makes it hard to know the exact position of the source and destination memory positions. This can be solved by allocating a scatterlist for each request, that will be keep until the request is finished, allowing us to copy the data back to the original memory without having to iterate over the raw request. Oracle-Bug: 16660413 - LARGE ASYNCHRONOUS READS APPEAR BROKEN ON 2.6.39-400 CC: stable@vger.kernel.org Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reported-and-Tested-by: Anne Milicia <anne.milicia@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-07block_device_operations->release() should return voidAl Viro1-2/+1
The value passed is 0 in all but "it can never happen" cases (and those only in a couple of drivers) *and* it would've been lost on the way out anyway, even if something tried to pass something meaningful. Just don't bother. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-18xen-block: implement indirect descriptorsRoger Pau Monne1-84/+406
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>
2013-03-19xen-blkfront: remove frame list from blk_shadowRoger Pau Monne1-5/+1
We already have the frame (pfn of the grant page) stored inside struct grant, so there's no need to keep an aditional list of mapped frames for a specific request. This reduces memory usage in blkfront. 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>
2013-03-19xen-blkfront: pre-allocate pages for requestsRoger Pau Monne1-41/+79
This prevents us from having to call alloc_page while we are preparing the request. Since blkfront was calling alloc_page with a spinlock held we used GFP_ATOMIC, which can fail if we are requesting a lot of pages since it is using the emergency memory pools. Allocating all the pages at init prevents us from having to call alloc_page, thus preventing possible failures. 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>
2013-03-19xen-blkfront: switch from llist to listRoger Pau Monne1-23/+18
The git commit f84adf4921ae3115502f44ff467b04bf2f88cf04 (xen-blkfront: drop the use of llist_for_each_entry_safe) was a stop-gate to fix a GCC4.1 bug. The appropiate way is to actually use an list instead of using an llist. As such this patch replaces the usage of llist with an list. Since we always manipulate the list while holding the io_lock, there's no need for additional locking (llist used previously is safe to use concurrently without additional locking). Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> CC: stable@vger.kernel.org [v1: Redid the git commit description] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-19xen-blkfront: replace kmalloc and then memcpy with kmemdupMihnea Dobrescu-Balaur1-2/+1
The benefits are: * code is cleaner * kmemdup adds additional debugging info useful for tracking the real place where memory was allocated (CONFIG_DEBUG_SLAB). Signed-off-by: Mihnea Dobrescu-Balaur <mihneadb@gmail.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-20xen-blkfront: drop the use of llist_for_each_entry_safeKonrad Rzeszutek Wilk1-3/+10
Replace llist_for_each_entry_safe with a while loop. llist_for_each_entry_safe can trigger a bug in GCC 4.1, so it's best to remove it and use a while loop and do the deletion manually. Specifically this bug can be triggered by hot-unplugging a disk, either by doing xm block-detach or by save/restore cycle. BUG: unable to handle kernel paging request at fffffffffffffff0 IP: [<ffffffffa0047223>] blkif_free+0x63/0x130 [xen_blkfront] The crash call trace is: ... bad_area_nosemaphore+0x13/0x20 do_page_fault+0x25e/0x4b0 page_fault+0x25/0x30 ? blkif_free+0x63/0x130 [xen_blkfront] blkfront_resume+0x46/0xa0 [xen_blkfront] xenbus_dev_resume+0x6c/0x140 pm_op+0x192/0x1b0 device_resume+0x82/0x1e0 dpm_resume+0xc9/0x1a0 dpm_resume_end+0x15/0x30 do_suspend+0x117/0x1e0 When drilling down to the assembler code, on newer GCC it does .L29: cmpq $-16, %r12 #, persistent_gnt check je .L30 #, out of the loop .L25: ... code in the loop testq %r13, %r13 # n je .L29 #, back to the top of the loop cmpq $-16, %r12 #, persistent_gnt check movq 16(%r12), %r13 # <variable>.node.next, n jne .L25 #, back to the top of the loop .L30: While on GCC 4.1, it is: L78: ... code in the loop testq %r13, %r13 # n je .L78 #, back to the top of the loop movq 16(%rbx), %r13 # <variable>.node.next, n jmp .L78 #, back to the top of the loop Which basically means that the exit loop condition instead of being: &(pos)->member != NULL; is: ; which makes the loop unbound. Since xen-blkfront is the only user of the llist_for_each_entry_safe macro remove it from llist.h. Orabug: 16263164 CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-12-18xen-blkfront: handle bvecs with partial dataRoger Pau Monne1-3/+4
Currently blkfront fails to handle cases in blkif_completion like the following: 1st loop in rq_for_each_segment * bv_offset: 3584 * bv_len: 512 * offset += bv_len * i: 0 2nd loop: * bv_offset: 0 * bv_len: 512 * i: 0 In the second loop i should be 1, since we assume we only wanted to read a part of the previous page. This patches fixes this cases where only a part of the shared page is read, and blkif_completion assumes that if the bv_offset of a bvec is less than the previous bv_offset plus the bv_size we have to switch to the next shared page. Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: linux-kernel@vger.kernel.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-12-18llist/xen-blkfront: implement safe version of llist_for_each_entryRoger Pau Monne1-1/+2
Implement a safe version of llist_for_each_entry, and use it in blkif_free. Previously grants where freed while iterating the list, which lead to dereferences when trying to fetch the next item. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> [v2: Move the llist_for_each_entry_safe in llist.h] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-26xen-blkfront: free allocated pageRoger Pau Monne1-0/+1
Free the page allocated for the persistent grant. 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 Monne1-1/+2
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 Monne1-28/+169
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]
2012-08-21workqueue: deprecate flush[_delayed]_work_sync()Tejun Heo1-2/+2
flush[_delayed]_work_sync() are now spurious. Mark them deprecated and convert all users to flush[_delayed]_work(). If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant and the regular flushes guarantee that the work item is not pending or running on any CPU on return, so there's no reason to use the sync flushes at all and they're going away. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mattia Dongili <malattia@linux.it> Cc: Kent Yoder <key@linux.vnet.ibm.com> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Bryan Wu <bryan.wu@canonical.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-wireless@vger.kernel.org Cc: Anton Vorontsov <cbou@mail.ru> Cc: Sangbeom Kim <sbkim73@samsung.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Petr Vandrovec <petr@vandrovec.name> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Avi Kivity <avi@redhat.com>
2012-08-01Merge tag 'random_for_linus' of ↵Linus Torvalds1-3/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull random subsystem patches from Ted Ts'o: "This patch series contains a major revamp of how we collect entropy from interrupts for /dev/random and /dev/urandom. The goal is to addresses weaknesses discussed in the paper "Mining your Ps and Qs: Detection of Widespread Weak Keys in Network Devices", by Nadia Heninger, Zakir Durumeric, Eric Wustrow, J. Alex Halderman, which will be published in the Proceedings of the 21st Usenix Security Symposium, August 2012. (See https://factorable.net for more information and an extended version of the paper.)" Fix up trivial conflicts due to nearby changes in drivers/{mfd/ab3100-core.c, usb/gadget/omap_udc.c} * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: (33 commits) random: mix in architectural randomness in extract_buf() dmi: Feed DMI table to /dev/random driver random: Add comment to random_initialize() random: final removal of IRQF_SAMPLE_RANDOM um: remove IRQF_SAMPLE_RANDOM which is now a no-op sparc/ldc: remove IRQF_SAMPLE_RANDOM which is now a no-op [ARM] pxa: remove IRQF_SAMPLE_RANDOM which is now a no-op board-palmz71: remove IRQF_SAMPLE_RANDOM which is now a no-op isp1301_omap: remove IRQF_SAMPLE_RANDOM which is now a no-op pxa25x_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op omap_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op goku_udc: remove IRQF_SAMPLE_RANDOM which was commented out uartlite: remove IRQF_SAMPLE_RANDOM which is now a no-op drivers: hv: remove IRQF_SAMPLE_RANDOM which is now a no-op xen-blkfront: remove IRQF_SAMPLE_RANDOM which is now a no-op n2_crypto: remove IRQF_SAMPLE_RANDOM which is now a no-op pda_power: remove IRQF_SAMPLE_RANDOM which is now a no-op i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op input/serio/hp_sdc.c: remove IRQF_SAMPLE_RANDOM which is now a no-op mfd: remove IRQF_SAMPLE_RANDOM which is now a no-op ...
2012-07-19xen-blkfront: remove IRQF_SAMPLE_RANDOM which is now a no-opTheodore Ts'o1-3/+2
With the changes in the random tree, IRQF_SAMPLE_RANDOM is now a no-op; interrupt randomness is now collected unconditionally in a very low-overhead fashion; see commit 775f4b297b. The IRQF_SAMPLE_RANDOM flag was scheduled to be removed in 2009 on the feature-removal-schedule, so this patch is preparation for the final removal of this flag. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2012-06-12xen/blkfront: Add WARN to deal with misbehaving backends.Konrad Rzeszutek Wilk1-12/+46
Part of the ring structure is the 'id' field which is under control of the frontend. The frontend stamps it with "some" value (this some in this implementation being a value less than BLK_RING_SIZE), and when it gets a response expects said value to be in the response structure. We have a check for the id field when spolling new requests but not when de-spolling responses. We also add an extra check in add_id_to_freelist to make sure that the 'struct request' was not NULL - as we cannot pass a NULL to __blk_end_request_all, otherwise that crashes (and all the operations that the response is dealing with end up with __blk_end_request_all). Lastly we also print the name of the operation that failed. [v1: s/BUG/WARN/ suggested by Stefano] [v2: Add extra check in add_id_to_freelist] [v3: Redid op_name per Jan's suggestion] [v4: add const * and add WARN on failure returns] Acked-by: Jan Beulich <jbeulich@suse.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-12xen-blkfront: module exit handling adjustmentsJan Beulich1-1/+3
The blkdev major must be released upon exit, or else the module can't attach to devices using the same majors upon being loaded again. Also avoid leaking the minor tracking bitmap. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-12xen-blkfront: properly name all devicesJan Beulich1-18/+22
- devices beyond xvdzz didn't get proper names assigned at all - extended devices with minors not representable within the kernel's major/minor bit split spilled into foreign majors Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-14Merge branch 'for-3.4/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-21/+20
Pull block driver bits from Jens Axboe: - A series of fixes for mtip32xx. Most from Asai at Micron, but also one from Greg, getting rid of the dependency on PCIE_HOTPLUG. - A few bug fixes for xen-blkfront, and blkback. - A virtio-blk fix for Vivek, making resize actually work. - Two fixes from Stephen, making larger transfers possible on cciss. This is needed for tape drive support. * 'for-3.4/drivers' of git://git.kernel.dk/linux-block: block: mtip32xx: remove HOTPLUG_PCI_PCIE dependancy mtip32xx: dump tagmap on failure mtip32xx: fix handling of commands in various scenarios mtip32xx: Shorten macro names mtip32xx: misc changes mtip32xx: Add new sysfs entry 'status' mtip32xx: make setting comp_time as common mtip32xx: Add new bitwise flag 'dd_flag' mtip32xx: fix error handling in mtip_init() virtio-blk: Call revalidate_disk() upon online disk resize xen/blkback: Make optional features be really optional. xen/blkback: Squash the discard support for 'file' and 'phy' type. mtip32xx: fix incorrect value set for drv_cleanup_done, and re-initialize and start port in mtip_restart_port() cciss: Fix scsi tape io with more than 255 scatter gather elements cciss: Initialize scsi host max_sectors for tape drive support xen-blkfront: make blkif_io_lock spinlock per-device xen/blkfront: don't put bdev right after getting it xen-blkfront: use bitmap_set() and bitmap_clear() xen/blkback: Enable blkback on HVM guests xen/blkback: use grant-table.c hypercall wrappers
2012-04-07Merge tag 'stable/for-linus-3.4-rc1-tag' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull xen fixes from Konrad Rzeszutek Wilk: "Two fixes for regressions: * one is a workaround that will be removed in v3.5 with proper fix in the tip/x86 tree, * the other is to fix drivers to load on PV (a previous patch made them only load in PVonHVM mode). The rest are just minor fixes in the various drivers and some cleanup in the core code." * tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pcifront: avoid pci_frontend_enable_msix() falsely returning success xen/pciback: fix XEN_PCI_OP_enable_msix result xen/smp: Remove unnecessary call to smp_processor_id() xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries' xen: only check xen_platform_pci_unplug if hvm
2012-04-06xen: only check xen_platform_pci_unplug if hvmIgor Mammedov1-1/+1
commit b9136d207f08 xen: initialize platform-pci even if xen_emul_unplug=never breaks blkfront/netfront by not loading them because of xen_platform_pci_unplug=0 and it is never set for PV guest. Signed-off-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-24Merge tag 'stable/for-linus-3.4-tag-two' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull more xen updates from Konrad Rzeszutek Wilk: "One tiny feature that accidentally got lost in the initial git pull: * Add fast-EOI acking of interrupts (clear a bit instead of hypercall) And bug-fixes: * Fix CPU bring-up code missing a call to notify other subsystems. * Fix reading /sys/hypervisor even if PVonHVM drivers are not loaded. * In Xen ACPI processor driver: remove too verbose WARN messages, fix up the Kconfig dependency to be a module by default, and add dependency on CPU_FREQ. * Disable CPU frequency drivers from loading when booting under Xen (as we want the Xen ACPI processor to be used instead). * Cleanups in tmem code." * tag 'stable/for-linus-3.4-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/acpi: Fix Kconfig dependency on CPU_FREQ xen: initialize platform-pci even if xen_emul_unplug=never xen/smp: Fix bringup bug in AP code. xen/acpi: Remove the WARN's as they just create noise. xen/tmem: cleanup xen: support pirq_eoi_map xen/acpi-processor: Do not depend on CPU frequency scaling drivers. xen/cpufreq: Disable the cpu frequency scaling drivers from loading. provide disable_cpufreq() function to disable the API.
2012-03-22xen: initialize platform-pci even if xen_emul_unplug=neverIgor Mammedov1-0/+3
When xen_emul_unplug=never is specified on kernel command line reading files from /sys/hypervisor is broken (returns -EBUSY). It is caused by xen_bus dependency on platform-pci and platform-pci isn't initialized when xen_emul_unplug=never is specified. Fix it by allowing platform-pci to ignore xen_emul_unplug=never, and do not intialize xen_[blk|net]front instead. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-20xen-blkfront: make blkif_io_lock spinlock per-deviceSteven Noonan1-16/+16
This patch moves the global blkif_io_lock to the per-device structure. The spinlock seems to exists for two reasons: to disable IRQs when in the interrupt handlers for blkfront, and to protect the blkfront VBDs when a detachment is requested. Having a global blkif_io_lock doesn't make sense given the use case, and it drastically hinders performance due to contention. All VBDs with pending IOs have to take the lock in order to get work done, which serializes everything pretty badly. Signed-off-by: Steven Noonan <snoonan@amazon.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-20xen/blkfront: don't put bdev right after getting itAndrew Jones1-1/+1
We should hang onto bdev until we're done with it. Signed-off-by: Andrew Jones <drjones@redhat.com> [v1: Fixed up git commit description] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-20xen-blkfront: use bitmap_set() and bitmap_clear()Akinobu Mita1-4/+3
Use bitmap_set and bitmap_clear rather than modifying individual bits in a memory region. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: xen-devel@lists.xensource.com Cc: virtualization@lists.linux-foundation.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-16Merge branch 'for-3.3/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-28/+51
* '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
2012-01-05Xen: consolidate and simplify struct xenbus_driver instantiationJan Beulich1-7/+4
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>
2011-12-16xen-blkfront: Use kcalloc instead of kzalloc to allocate arrayThomas Meyer1-1/+1
The advantage of kcalloc is, that will prevent integer overflows which could result from the multiplication of number of elements and size and it is also a bit nicer to read. The semantic patch that makes this change is available in https://lkml.org/lkml/2011/11/25/107 Signed-off-by: Thomas Meyer <thomas@m3y3r.de> [v1: Seperated the drivers/block/cciss_scsi.c out of this patch] 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 Wilk1-10/+31
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 Wilk1-21/+23
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>
2011-11-05Merge branch 'for-3.2/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-25/+98
* '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
2011-10-13xen-blkfront: plug device number leak in xlblk_init() error pathLaszlo Ersek1-1/+9
... though after a failed xenbus_register_frontend() all may be lost. Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen-blkfront: If no barrier or flush is supported, use invalid operation.Konrad Rzeszutek Wilk1-1/+3
Guard against issuing BLKIF_OP_WRITE_BARRIER or BLKIF_OP_FLUSH_CACHE by checking whether we successfully negotiated with the backend. The negotiation with the backend also sets the q->flush_flags which fortunately for us is also used when submitting an bio to us. If we don't support barriers or flushes it would be set to zero so we should never end up having to deal with REQ_FLUSH | REQ_FUA. However, other third party implementations of __make_request that might be stacked on top of us might not be so smart, so lets fix this up. Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen-blkfront: fix a deadlock while handling discard responseLi Dongyang1-2/+0
When we get -EOPNOTSUPP response for a discard request, we will clear the discard flag on the request queue so we won't attempt to send discard requests to backend again, and this should be protected under rq->queue_lock. However, when we setup the request queue, we pass blkif_io_lock to blk_init_queue so rq->queue_lock is blkif_io_lock indeed, and this lock is already taken when we are in blkif_interrpt, so remove the spin_lock/spin_unlock when we clear the discard flag or we will end up with deadlock here Signed-off-by: Li Dongyang <lidongyang@novell.com> [v1: Updated description a bit and removed comment from source] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13xen-blkfront: Handle discard requests.Li Dongyang1-23/+88
If the backend advertises 'feature-discard', then interrogate the backend for alignment and granularity. Setup the request queue with the appropiate values and send the discard operation as required. Signed-off-by: Li Dongyang <lidongyang@novell.com> [v1: Amended commit description] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-14xen-blkfront: Fix one off warning about name clashStefan Bader1-1/+1
Avoid telling users to use xvde and onwards when using xvde. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-14xen-blkfront: Drop name and minor adjustments for emulated scsi devicesStefan Bader1-2/+2
These were intended to avoid the namespace clash when representing emulated IDE and SCSI devices. However that seems to confuse users more than expected (a disk defined as sda becomes xvde). So for now go back to the scheme which does no adjustments. This will break when mixing IDE and SCSI names in the configuration of guests but should be by now expected. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen-blkfront: Introduce BLKIF_OP_FLUSH_DISKCACHE support.Konrad Rzeszutek Wilk1-13/+36
If the backend supports the 'feature-flush-cache' mode, use that instead of the 'feature-barrier' support. Currently there are three backends that support the 'feature-flush-cache' mode: NetBSD, Solaris and Linux kernel. The 'flush' option is much light-weight version than the 'barrier' support so lets try to use as there are no filesystems in the kernel that use full barriers anymore. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen-blkfront: fix data size for xenbus_gather in blkfront_connectMarek Marczykowski1-1/+1
barrier variable is int, not long. This overflow caused another variable override: "err" (in PV code) and "binfo" (in xenlinux code - drivers/xen/blkfront/blkfront.c). The later caused incorrect device flags (RO/removable etc). Signed-off-by: Marek Marczykowski <marmarek@mimuw.edu.pl> Acked-by: Ian Campbell <Ian.Campbell@citrix.com> [v1: Changed title] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-15Merge branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvmLinus Torvalds1-5/+74
* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm: xen: suspend: remove xen_hvm_suspend xen: suspend: pull pre/post suspend hooks out into suspend_info xen: suspend: move arch specific pre/post suspend hooks into generic hooks xen: suspend: refactor non-arch specific pre/post suspend hooks xen: suspend: add "arch" to pre/post suspend hooks xen: suspend: pass extra hypercall argument via suspend_info struct xen: suspend: refactor cancellation flag into a structure xen: suspend: use HYPERVISOR_suspend for PVHVM case instead of open coding xen: switch to new schedop hypercall by default. xen: use new schedop interface for suspend xen: do not respond to unknown xenstore control requests xen: fix compile issue if XEN is enabled but XEN_PVHVM is disabled xen: PV on HVM: support PV spinlocks and IPIs xen: make the ballon driver work for hvm domains xen-blkfront: handle Xen major numbers other than XENVBD xen: do not use xen_info on HVM, set pv_info name to "Xen HVM" xen: no need to delay xen_setup_shutdown_event for hvm guests anymore
2011-03-08xen: Union the blkif_request request specific fieldsOwen Smith1-4/+4
Prepare for extending the block device ring to allow request specific fields, by moving the request specific fields for reads, writes and barrier requests to a union member. Acked-by: Jens Axboe <jaxboe@fusionio.com> Signed-off-by: Owen Smith <owen.smith@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-02-25xen-blkfront: handle Xen major numbers other than XENVBDStefano Stabellini1-5/+74
This patch makes sure blkfront handles correctly virtual device numbers corresponding to Xen emulated IDE and SCSI disks: in those cases blkfront translates the major number to XENVBD and the minor number to a low xvd minor. Note: this behaviour is different from what old xenlinux PV guests used to do: they used to steal an IDE or SCSI major number and use it instead. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
2011-01-08Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-2/+2
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (33 commits) usb: don't use flush_scheduled_work() speedtch: don't abuse struct delayed_work media/video: don't use flush_scheduled_work() media/video: explicitly flush request_module work ioc4: use static work_struct for ioc4_load_modules() init: don't call flush_scheduled_work() from do_initcalls() s390: don't use flush_scheduled_work() rtc: don't use flush_scheduled_work() mmc: update workqueue usages mfd: update workqueue usages dvb: don't use flush_scheduled_work() leds-wm8350: don't use flush_scheduled_work() mISDN: don't use flush_scheduled_work() macintosh/ams: don't use flush_scheduled_work() vmwgfx: don't use flush_scheduled_work() tpm: don't use flush_scheduled_work() sonypi: don't use flush_scheduled_work() hvsi: don't use flush_scheduled_work() xen: don't use flush_scheduled_work() gdrom: don't use flush_scheduled_work() ... Fixed up trivial conflict in drivers/media/video/bt8xx/bttv-input.c as per Tejun.
2010-12-24xen: don't use flush_scheduled_work()Tejun Heo1-2/+2
flush_scheduled_work() is deprecated and scheduled to be removed. Directly flush info->work instead. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>