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2016-07-20iscsi: Switch .bdrv_co_discard() to byte-basedEric Blake
Another step towards killing off sector-based block APIs. Unlike write_zeroes, where we can be handed unaligned requests and must fail gracefully with -ENOTSUP for a fallback, we are guaranteed that discard requests are always aligned because the block layer already ignored unaligned head/tail. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1468624988-423-13-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20iscsi: Rely on block layer to break up large requestsEric Blake
Now that the block layer honors max_request, we don't need to bother with an EINVAL on overlarge requests, but can instead assert that requests are well-behaved. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1468607524-19021-7-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-19block/iscsi: allow caching of the allocation mapPeter Lieven
until now the allocation map was used only as a hint if a cluster is allocated or not. If a block was not allocated (or Qemu had no info about the allocation status) a get_block_status call was issued to check the allocation status and possibly avoid a subsequent read of unallocated sectors. If a block known to be allocated the get_block_status call was omitted. In the other case a get_block_status call was issued before every read to avoid the necessity for a consistent allocation map. To avoid the potential overhead of calling get_block_status for each and every read request this took only place for the bigger requests. This patch enhances this mechanism to cache the allocation status and avoid calling get_block_status for blocks where the allocation status has been queried before. This allows for bypassing the read request even for smaller requests and additionally omits calling get_block_status for known to be unallocated blocks. Signed-off-by: Peter Lieven <pl@kamp.de> Message-Id: <1468831940-15556-3-git-send-email-pl@kamp.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-19block/iscsi: fix rounding in iscsi_allocationmap_setPeter Lieven
when setting clusters as alloacted the boundaries have to be expanded. As Paolo pointed out the calculation of the number of clusters is wrong: Suppose cluster_sectors is 2, sector_num = 1, nb_sectors = 6: In the "mark allocated" case, you want to set 0..8, i.e. cluster_num=0, nb_clusters=4. 0--.--2--.--4--.--6--.--8 <--|_________________|--> (<--> = expanded) Instead you are setting nb_clusters=3, so that 6..8 is not marked. 0--.--2--.--4--.--6--.--8 <--|______________|!!! (! = wrong) Cc: qemu-stable@nongnu.org Reported-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Message-Id: <1468831940-15556-2-git-send-email-pl@kamp.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-13coroutine: move entry argument to qemu_coroutine_createPaolo Bonzini
In practice the entry argument is always known at creation time, and it is confusing that sometimes qemu_coroutine_enter is used with a non-NULL argument to re-enter a coroutine (this happens in block/sheepdog.c and tests/test-coroutine.c). So pass the opaque value at creation time, for consistency with e.g. aio_bh_new. Mostly done with the following semantic patch: @ entry1 @ expression entry, arg, co; @@ - co = qemu_coroutine_create(entry); + co = qemu_coroutine_create(entry, arg); ... - qemu_coroutine_enter(co, arg); + qemu_coroutine_enter(co); @ entry2 @ expression entry, arg; identifier co; @@ - Coroutine *co = qemu_coroutine_create(entry); + Coroutine *co = qemu_coroutine_create(entry, arg); ... - qemu_coroutine_enter(co, arg); + qemu_coroutine_enter(co); @ entry3 @ expression entry, arg; @@ - qemu_coroutine_enter(qemu_coroutine_create(entry), arg); + qemu_coroutine_enter(qemu_coroutine_create(entry, arg)); @ reentry @ expression co; @@ - qemu_coroutine_enter(co, NULL); + qemu_coroutine_enter(co); except for the aforementioned few places where the semantic patch stumbled (as expected) and for test_co_queue, which would otherwise produce an uninitialized variable warning. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-12Use #include "..." for our own headers, <...> for othersMarkus Armbruster
Tracked down with an ugly, brittle and probably buggy Perl script. Also move includes converted to <...> up so they get included before ours where that's obviously okay. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Tested-by: Eric Blake <eblake@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-05block: Use bool as appropriate for BDS membersEric Blake
Using int for values that are only used as booleans is confusing. While at it, rearrange a couple of members so that all the bools are contiguous. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Move request_alignment into BlockLimitEric Blake
It makes more sense to have ALL block size limit constraints in the same struct. Improve the documentation while at it. Simplify a couple of conditionals, now that we have audited and documented that request_alignment is always non-zero. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Switch discard length bounds to byte-basedEric Blake
Sector-based limits are awkward to think about; in our on-going quest to move to byte-based interfaces, convert max_discard and discard_alignment. Rename them, using 'pdiscard' as an aid to track which remaining discard interfaces need conversion, and so that the compiler will help us catch the change in semantics across any rebased code. The BlockLimits type is now completely byte-based; and in iscsi.c, sector_limits_lun2qemu() is no longer needed. pdiscard_alignment is made unsigned (we use power-of-2 alignments as bitmasks, where unsigned is easier to think about) while leaving max_pdiscard signed (since we still have an 'int' interface); this is comparable to what commit cf081fc did for write zeroes limits. We may later want to make everything an unsigned 64-bit limit - but that requires a bigger code audit. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Switch transfer length bounds to byte-basedEric Blake
Sector-based limits are awkward to think about; in our on-going quest to move to byte-based interfaces, convert max_transfer_length and opt_transfer_length. Rename them (dropping the _length suffix) so that the compiler will help us catch the change in semantics across any rebased code, and improve the documentation. Use unsigned values, so that we don't have to worry about negative values and so that bit-twiddling is easier; however, we are still constrained by 2^31 of signed int in most APIs. When a value comes from an external source (iscsi and raw-posix), sanitize the results to ensure that opt_transfer is a power of 2. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05iscsi: Set request_alignment during .bdrv_refresh_limits()Eric Blake
We want to eventually stick request_alignment alongside other BlockLimits, but first, we must ensure it is populated at the same time as all other limits, rather than being a special case that is set only when a block is first opened. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05iscsi: Advertise realistic limits to block layerEric Blake
The function sector_limits_lun2qemu() returns a value in units of the block layer's 512-byte sector, and can be as large as 0x40000000, which is much larger than the block layer's inherent limit of BDRV_REQUEST_MAX_SECTORS. The block layer already handles '0' as a synonym to the inherent limit, and it is nicer to return this value than it is to calculate an arbitrary maximum, for two reasons: we want to ensure that the block layer continues to special-case '0' as 'no limit beyond the inherent limits'; and we want to be able to someday expand the block layer to allow 64-bit limits, where auditing for uses of BDRV_REQUEST_MAX_SECTORS will help us make sure we aren't artificially constraining iscsi to old block layer limits. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-29iscsi: fix assertion in is_sector_request_lun_alignedPeter Lieven
Commit 94d047a added an assertion the the request alignment check. This introduced 2 issues: a) A off-by-one error since a request of BDRV_REQUEST_MAX_SECTORS is actually allowed. b) The bdrv_get_block_status call in the read path to check the allocation status requests up to INT_MAX sectors which triggers the assertion. Fixes: 94d047a35bf663e28f8fef137544d8ea78165add Signed-off-by: Peter Lieven <pl@kamp.de> Message-Id: <1466414680-18383-1-git-send-email-pl@kamp.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-08iscsi: Convert to bdrv_co_pwrite_zeroes()Eric Blake
Another step on our continuing quest to switch to byte-based interfaces. As this is the first byte-based iscsi interface, convert is_request_lun_aligned() into two versions, one for sectors and one for bytes. Also, change from outright -EINVAL failure on an unaligned request, to instead failing with -ENOTSUP to trigger a read-modify-write fallback, particularly since the block layer should be honoring bs->request_alignment to avoid -EINVAL on read/write requests. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08block: Track write zero limits in bytesEric Blake
Another step towards removing sector-based interfaces: convert the maximum write and minimum alignment values from sectors to bytes. Rename the variables to let the compiler check that all users are converted to the new semantics. The maximum remains an int as long as BDRV_REQUEST_MAX_SECTORS is constrained by INT_MAX (this means that we can't even support a 2G write_zeroes, but just under it) - changing operation lengths to unsigned or to 64-bits is a much bigger audit, and debatable if we even want to do it (since at the core, a 32-bit platform will still have ssize_t as its underlying limit on write()). Meanwhile, alignment is changed to 'uint32_t', since it makes no sense to have an alignment larger than the maximum write, and less painful to use an unsigned type with well-defined behavior in bit operations than to have to worry about what happens if a driver mistakenly supplies a negative alignment. Add an assert that no one was trying to use sectors to get a write zeroes larger than 2G, and therefore that a later conversion to bytes won't be impacted by keeping the limit at 32 bits. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08iscsi: Use block size as minimum zero/discard alignmentEric Blake
If hardware does not advertise a minimum zero/discard alignment, we still want to guarantee that the block layer will align requests to our blocks, rather than the arbitrary 512-byte BDRV sector size. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-29block/iscsi: avoid potential overflow of acb->task->cdbPeter Lieven
at least in the path via virtio-blk the maximum size is not restricted. Cc: qemu-stable@nongnu.org Signed-off-by: Peter Lieven <pl@kamp.de> Message-Id: <1464080368-29584-1-git-send-email-pl@kamp.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-23iscsi: pass SCSI status back for SG_IOVadim Rozenfeld
Signed-off-by: Vadim Rozenfeld <vrozenfe@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-12block: Honor BDRV_REQ_FUA during write_zeroesEric Blake
The block layer has a couple of cases where it can lose Force Unit Access semantics when writing a large block of zeroes, such that the request returns before the zeroes have been guaranteed to land on underlying media. SCSI does not support FUA during WRITESAME(10/16); FUA is only supported if it falls back to WRITE(10/16). But where the underlying device is new enough to not need a fallback, it means that any upper layer request with FUA semantics was silently ignoring BDRV_REQ_FUA. Conversely, NBD has situations where it can support FUA but not ZERO_WRITE; when that happens, the generic block layer fallback to bdrv_driver_pwritev() (or the older bdrv_co_writev() in qemu 2.6) was losing the FUA flag. The problem of losing flags unrelated to ZERO_WRITE has been latent in bdrv_co_do_write_zeroes() since commit aa7bfbff, but back then, it did not matter because there was no FUA flag. It became observable when commit 93f5e6d8 paved the way for flags that can impact correctness, when we should have been using bdrv_co_writev_flags() with modified flags. Compare to commit 9eeb6dd, which got flag manipulation right in bdrv_co_do_zero_pwritev(). Symptoms: I tested with qemu-io with default writethrough cache (which is supposed to use FUA semantics on every write), and targetted an NBD client connected to a server that intentionally did not advertise NBD_FLAG_SEND_FUA. When doing 'write 0 512', the NBD client sent two operations (NBD_CMD_WRITE then NBD_CMD_FLUSH) to get the fallback FUA semantics; but when doing 'write -z 0 512', the NBD client sent only NBD_CMD_WRITE. The fix is do to a cleanup bdrv_co_flush() at the end of the operation if any step in the middle relied on a BDS that does not natively support FUA for that step (note that we don't need to flush after every operation, if the operation is broken into chunks based on bounce-buffer sizing). Each BDS gains a new flag .supported_zero_flags, which parallels the use of .supported_write_flags but only when accessing a zero write operation (the flags MUST be different, because of SCSI having different semantics based on WRITE vs. WRITESAME; and also because BDRV_REQ_MAY_UNMAP only makes sense on zero writes). Also fix some documentation to describe -ENOTSUP semantics, particularly since iscsi depends on those semantics. Down the road, we may want to add a driver where its .bdrv_co_pwritev() honors all three of BDRV_REQ_FUA, BDRV_REQ_ZERO_WRITE, and BDRV_REQ_MAY_UNMAP, and advertise this via bs->supported_write_flags for blocks opened by that driver; such a driver should NOT supply .bdrv_co_write_zeroes nor .supported_zero_flags. But none of the drivers touched in this patch want to do that (the act of writing zeroes is different enough from normal writes to deserve a second callback). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12block: Make supported_write_flags a per-bds propertyEric Blake
Pre-patch, .supported_write_flags lives at the driver level, which means we are blindly declaring that all block devices using a given driver will either equally support FUA, or that we need a fallback at the block layer. But there are drivers where FUA support is a per-block decision: the NBD block driver is dependent on the remote server advertising NBD_FLAG_SEND_FUA (and has fallback code to duplicate the flush that the block layer would do if NBD had not set .supported_write_flags); and the iscsi block driver is dependent on the mode sense bits advertised by the underlying device (and is currently silently ignoring FUA requests if the underlying device does not support FUA). The fix is to make supported flags as a per-BDS option, set during .bdrv_open(). This patch moves the variable and fixes NBD and iscsi to set it only conditionally; later patches will then further simplify the NBD driver to quit duplicating work done at the block layer, as well as tackle the fact that SCSI does not support FUA semantics on WRITESAME(10/16) but only on WRITE(10/16). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12block: Introduce bdrv_driver_pwritev()Kevin Wolf
This is a function that simply calls into the block driver for doing a write, providing the byte granularity interface we want to eventually have everywhere, and using whatever interface that driver supports. This one is a bit more interesting than the version for reads: It adds support for .bdrv_co_writev_flags() everywhere, so that drivers implementing this function can drop .bdrv_co_writev() now. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
2016-03-30iscsi: Support BDRV_REQ_FUAKevin Wolf
This replaces the existing hack in the iscsi driver that sent the FUA bit in writethrough mode and ignored the following flush in order to optimise the number of roundtrips (see commit 73b5394e). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30block: Move enable_write_cache to BB levelKevin Wolf
Whether a write cache is used or not is a decision that concerns the user (e.g. the guest device) rather than the backend. It was already logically part of the BB level as bdrv_move_feature_fields() always kept it on top of the BDS tree; with this patch, the core of it (the actual flag and the additional flushes) is also implemented there. Direct callers of bdrv_open() must pass BDRV_O_CACHE_WB now if bs doesn't have a BlockBackend attached. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-02-29iscsi: add support for getting CHAP password via QCryptoSecret APIDaniel P. Berrange
The iSCSI driver currently accepts the CHAP password in plain text as a block driver property. This change adds a new "password-secret" property that accepts the ID of a QCryptoSecret instance. $QEMU \ -object secret,id=sec0,filename=/home/berrange/example.pw \ -drive driver=iscsi,url=iscsi://example.com/target-foo/lun1,\ user=dan,password-secret=sec0 Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-id: 1453385961-10718-4-git-send-email-berrange@redhat.com Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-02-02iscsi: Assign bs to file in iscsi_co_get_block_statusFam Zheng
Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1453780743-16806-6-git-send-email-famz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-02-02block: Add "file" output parameter to block status query functionsFam Zheng
The added parameter can be used to return the BDS pointer which the valid offset is referring to. Its value should be ignored unless BDRV_BLOCK_OFFSET_VALID in ret is set. Until block drivers fill in the right value, let's clear it explicitly right before calling .bdrv_get_block_status. The "bs->file" condition in bdrv_co_get_block_status is kept now to keep iotest case 102 passing, and will be fixed once all drivers return the right file pointer. Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1453780743-16806-2-git-send-email-famz@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-01-20block: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-15iscsi: send readcapacity10 when readcapacity16 failedZhu Lingshan
When play with Dell MD3000 target, for sure it is a TYPE_DISK, but readcapacity16 would fail. Then we find that readcapacity10 succeeded. It looks like the target just support readcapacity10 even through it is a TYPE_DISK or have some TYPE_ROM characteristics. This patch can give a chance to send readcapacity16 when readcapacity10 failed. This patch is not harmful to original pathes Signed-off-by: Zhu Lingshan <lszhu@suse.com> Message-Id: <1451359934-9236-1-git-send-email-lszhu@suse.com> [Don't fall through on UNIT ATTENTION. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-11iscsi: fix readcapacity error messageZhu Lingshan
fix:The error message for readcapacity 16 incorrectly mentioned a readcapacity 10 failure, fixed the error message. Signed-off-by: Zhu Lingshan <lszhu@suse.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-11-12block: Drop BlockDriver.bdrv_ioctlFam Zheng
Now the callback is not used any more, drop the field along with all implementations in block drivers, which are iscsi and raw. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-id: 1447064214-29930-8-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-11-12iscsi: Emulate commands in iscsi_aio_ioctl as iscsi_ioctlFam Zheng
iscsi_ioctl emulates SG_GET_VERSION_NUM and SG_GET_SCSI_ID. Now that bdrv_ioctl() will be emulated with .bdrv_aio_ioctl, replicate the logic into iscsi_aio_ioctl to make them consistent. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-id: 1447064214-29930-5-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-11-05iscsi: Translate scsi sense into error codeFam Zheng
Previously we return -EIO blindly when anything goes wrong. Add a helper function to parse sense fields and try to make the return code more meaningful. This also fixes the default werror configuration (enospc) when we're using qcow2 on an iscsi lun. The old -EIO not being treated as out of space error failed to trigger vm stop. Signed-off-by: Fam Zheng <famz@redhat.com> Message-Id: <1446699609-11376-1-git-send-email-famz@redhat.com> [libiscsi 1.9 compatibility - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-23aio: Add "is_external" flag for event handlersFam Zheng
All callers pass in false, and the real external ones will switch to true in coming patches. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-09-07block/iscsi: validate block size returned from targetPeter Lieven
It has been reported that at least tgtd returns a block size of 0 for LUN 0. To avoid running into divide by zero later on and protect against other problematic block sizes validate the block size right at connection time. Cc: qemu-stable@nongnu.org Reported-by: Andrey Korolyov <andrey@xdel.ru> Signed-off-by: Peter Lieven <pl@kamp.de> Message-Id: <1439552016-8557-1-git-send-email-pl@kamp.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-02block/iscsi: restore compatiblity with libiscsi 1.9.0Peter Lieven
RHEL7 and others are stuck with libiscsi 1.9.0 since there unfortunately was an ABI breakage after that release. Signed-off-by: Peter Lieven <pl@kamp.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1435313881-19366-1-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-07-02block/iscsi: add support for request timeoutsPeter Lieven
libiscsi starting with 1.15 will properly support timeout of iscsi commands. The default will remain no timeout, but this can be changed via cmdline parameters, e.g.: qemu -iscsi timeout=30 -drive file=iscsi://... If a timeout occurs a reconnect is scheduled and the timed out command will be requeued for processing after a successful reconnect. The required API call iscsi_set_timeout is present since libiscsi 1.10 which was released in October 2013. However, due to some bugs in the libiscsi code the use is not recommended before version 1.15. Please note that this patch bumps the libiscsi requirement to 1.10 to have all function and macros defined. The patch fixes also a off-by-one error in the NOP timeout calculation which was fixed while touching these code parts. Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1434455107-19328-1-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-06-23Fix migration in case of scsi-genericDimitris Aragiorgis
During migration, QEMU uses fsync()/fdatasync() on the open file descriptor for read-write block devices to flush data just before stopping the VM. However, fsync() on a scsi-generic device returns -EINVAL which causes the migration to fail. This patch skips flushing data in case of an SG device, since submitting SCSI commands directly via an SG character device (e.g. /dev/sg0) bypasses the page cache completely, anyway. Note that fsync() not only flushes the page cache but also the disk cache. The scsi-generic device never sends flushes, and for migration it assumes that the same SCSI device is used by the destination host, so it does not issue any SCSI SYNCHRONIZE CACHE (10) command. Finally, remove the bdrv_is_sg() test from iscsi_co_flush() since this is now redundant (we flush the underlying protocol at the end of bdrv_co_flush() which, with this patch, we never reach). Signed-off-by: Dimitris Aragiorgis <dimara@arrikto.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1435056300-14924-3-git-send-email-dimara@arrikto.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-06-23block: Use bdrv_is_sg() everywhereDimitris Aragiorgis
Instead of checking bs->sg use bdrv_is_sg() consistently throughout the code. Signed-off-by: Dimitris Aragiorgis <dimara@arrikto.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1435056300-14924-2-git-send-email-dimara@arrikto.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-06-22qerror: Move #include out of qerror.hMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-03iscsi: Remove pointless runtime check of macro valueFam Zheng
raw_bsd already has QEMU_BUILD_BUG_ON(BDRV_SECTOR_SIZE != 512), so iscsi should relax. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-04-28block/iscsi: use the allocationmap also if cache.direct=onPeter Lieven
the allocationmap has only a hint character. The driver always double checks that blocks marked unallocated in the cache are still unallocated before taking the fast path and return zeroes. So using the allocationmap is migration safe and can also be enabled with cache.direct=on. Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-10-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: bump year in copyright noticePeter Lieven
Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-9-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: handle SCSI_STATUS_TASK_SET_FULLPeter Lieven
a target may issue a SCSI_STATUS_TASK_SET_FULL status if there is more than one "BUSY" command queued already. Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-8-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: increase retry countPeter Lieven
The idea is that a command is retried in a BUSY condition up a time of approx. 60 seconds before it is failed. This should be far higher than any command timeout in the guest. Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-7-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: optimize WRITE10/16 if cache.writeback is not setPeter Lieven
SCSI allowes to tell the target to not return from a write command if the date is not written to the disk. Use this so called FUA bit if it is supported to optimize WRITE commands if writeback is not allowed. In this case qemu always issues a WRITE followed by a FLUSH. This is 2 round trip times. If we set the FUA bit we can ignore the following FLUSH. Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-6-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: store DPOFUA bit from the modesense commandPeter Lieven
Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-5-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: rename iscsi_write_protected and let it return voidPeter Lieven
Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-4-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: change all iscsilun properties from uint8_t to boolPeter Lieven
Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-3-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/iscsi: do not forget to logout from targetPeter Lieven
We actually were always impolitely dropping the connection and not cleanly logging out. CC: qemu-stable@nongnu.org Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1429193313-4263-2-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-09block/iscsi: handle zero events from iscsi_which_eventsPeter Lieven
newer libiscsi versions may return zero events from iscsi_which_events. In this case iscsi_service will return immediately without any progress. To avoid busy waiting for iscsi_which_events to change we deregister all read and write handlers in this case and schedule a timer to periodically check iscsi_which_events for changed events. Next libiscsi version will introduce async reconnects and zero events are returned while libiscsi is waiting for a reconnect retry. Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1428437295-29577-1-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>