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2014-12-16Start migrating migration code into a migration directoryDr. David Alan Gilbert1-892/+0
The migration code now occupies a fair chunk of the top level .c files, it seems time to give it it's own directory. I've not touched: arch_init.c - that's mostly RAM migration but has a few random other bits savevm.c - because it's built target specific This is purely a code move; no code has changed. - it fails checkpatch because of old violations, it feels safer to keep this as purely a move and fix those at some mythical future date. The xbzrle and vmstate tests are now only run for softmmu builds since they require files in the migrate/ directory which is only built for softmmu. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2014-12-12block migration: fix return valueGary R Hook1-1/+9
Modify block_save_iterate() to return positive/zero/negative (success/not done/failure) return status. The computation of the blocks transferred (an int64_t) exceeds the size of an int return value. Signed-off-by: Gary R Hook <gary.hook@nimboxx.com> Reviewed-by: ChenLiang <chenliang88@huawei.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1416958202-15913-1-git-send-email-gary.hook@nimboxx.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-10-20block: Rename BlockDriverAIOCB* to BlockAIOCB*Markus Armbruster1-1/+1
I'll use BlockDriverAIOCB with block backends shortly, and the name is going to fit badly there. It's a block layer thing anyway, not just a block driver thing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Eliminate BlockDriverState member device_name[]Markus Armbruster1-5/+7
device_name[] can become non-empty only in bdrv_new_root() and bdrv_move_feature_fields(). The latter is used only to undo damage done by bdrv_swap(). The former is called only by blk_new_with_bs(). Therefore, when a BlockDriverState's device_name[] is non-empty, then it's been created with a BlockBackend, and vice versa. Furthermore, blk_new_with_bs() keeps the two names equal. Therefore, device_name[] is redundant. Eliminate it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Eliminate bdrv_iterate(), use bdrv_next()Markus Armbruster1-15/+15
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: BenoƮt Canet <benoit.canet@nodalink.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-20block: Use g_new() & friends where that makes obvious senseMarkus Armbruster1-3/+3
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer, for two reasons. One, it catches multiplication overflowing size_t. Two, it returns T * rather than void *, which lets the compiler catch more type errors. Patch created with Coccinelle, with two manual changes on top: * Add const to bdrv_iterate_format() to keep the types straight * Convert the allocation in bdrv_drop_intermediate(), which Coccinelle inexplicably misses Coccinelle semantic patch: @@ type T; @@ -g_malloc(sizeof(T)) +g_new(T, 1) @@ type T; @@ -g_try_malloc(sizeof(T)) +g_try_new(T, 1) @@ type T; @@ -g_malloc0(sizeof(T)) +g_new0(T, 1) @@ type T; @@ -g_try_malloc0(sizeof(T)) +g_try_new0(T, 1) @@ type T; expression n; @@ -g_malloc(sizeof(T) * (n)) +g_new(T, n) @@ type T; expression n; @@ -g_try_malloc(sizeof(T) * (n)) +g_try_new(T, n) @@ type T; expression n; @@ -g_malloc0(sizeof(T) * (n)) +g_new0(T, n) @@ type T; expression n; @@ -g_try_malloc0(sizeof(T) * (n)) +g_try_new0(T, n) @@ type T; expression p, n; @@ -g_realloc(p, sizeof(T) * (n)) +g_renew(T, p, n) @@ type T; expression p, n; @@ -g_try_realloc(p, sizeof(T) * (n)) +g_try_renew(T, p, n) Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-15block: Use bdrv_nb_sectors() where sectors, not bytes are wantedMarkus Armbruster1-5/+4
Instead of bdrv_getlength(). Aside: a few of these callers don't handle errors. I didn't investigate whether they should. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-18migration: Add missing 'static' attributeStefan Weil1-1/+1
Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-06-04block: fix wrong order in live block migration setupchai wen1-2/+1
The function init_blk_migration is better to be called before set_dirty_tracking as the reasons below. If we want to track dirty blocks via dirty_maps on a BlockDriverState when doing live block-migration, its correspoding 'BlkMigDevState' should be added to block_mig_state.bmds_list first for subsequent processing. Otherwise set_dirty_tracking will do nothing on an empty list than allocating dirty_bitmaps for them. And bdrv_get_dirty_count will access the bmds->dirty_maps directly, then there would be a segfault triggered. If the set_dirty_tracking fails, qemu_savevm_state_cancel will handle the cleanup of init_blk_migration automatically. Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: chai wen <chaiw.fnst@cn.fujitsu.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-05-28block: Replace in_use with operation blockerFam Zheng1-2/+5
This drops BlockDriverState.in_use with op_blockers: - Call bdrv_op_block_all in place of bdrv_set_in_use(bs, 1). - Call bdrv_op_unblock_all in place of bdrv_set_in_use(bs, 0). - Check bdrv_op_is_blocked() in place of bdrv_in_use(bs). The specific types are used, e.g. in place of starting block backup, bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP, ...). There is one exception in block_job_create, where bdrv_op_blocker_is_empty() is used, because we don't know the operation type here. This doesn't matter because in a few commits away we will drop the check and move it to callers that _do_ know the type. - Check bdrv_op_blocker_is_empty() in place of assert(!bs->in_use). Note: there is only bdrv_op_block_all and bdrv_op_unblock_all callers at this moment. So although the checks are specific to op types, this changes can still be seen as identical logic with previously with in_use. The difference is error message are improved because of blocker error info. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-22block: Handle error of bdrv_getlength in bdrv_create_dirty_bitmapFam Zheng1-4/+26
bdrv_getlength could fail, check the return value before using it. Return NULL and set errno if it fails. Callers are updated to handle the error case. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-11-29block: per caller dirty bitmapFam Zheng1-6/+16
Previously a BlockDriverState has only one dirty bitmap, so only one caller (e.g. a block job) can keep track of writing. This changes the dirty bitmap to a list and creates a BdrvDirtyBitmap for each caller, the lifecycle is managed with these new functions: bdrv_create_dirty_bitmap bdrv_release_dirty_bitmap Where BdrvDirtyBitmap is a linked list wrapper structure of HBitmap. In place of bdrv_set_dirty_tracking, a BdrvDirtyBitmap pointer argument is added to these functions, since each caller has its own dirty bitmap: bdrv_get_dirty bdrv_dirty_iter_init bdrv_get_dirty_count bdrv_set_dirty and bdrv_reset_dirty prototypes are unchanged but will internally walk the list of all dirty bitmaps and set them one by one. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-11-28block: introduce BDRV_REQ_MAY_UNMAP request flagPeter Lieven1-1/+2
Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28block: add flags to bdrv_*_write_zeroesPeter Lieven1-1/+1
Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06migration: omit drive ref as we have bdrv_ref nowFam Zheng1-2/+2
block-migration.c does not actually use DriveInfo anywhere. Hence it's safe to drive ref code, we really only care about referencing BDS. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-19block-migration: efficiently encode zero blocksPeter Lieven1-6/+26
this patch adds a efficient encoding for zero blocks by adding a new flag indicating a block is completely zero. additionally bdrv_write_zeros() is used at the destination to efficiently write these zeroes. depending on the implementation this avoids that the destination target gets fully provisioned. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-11migration: run setup callbacks out of big lockPaolo Bonzini1-0/+2
Only the migration_bitmap_sync() call needs the iothread lock. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11migration: run pending/iterate callbacks out of big lockPaolo Bonzini1-2/+35
This makes it possible to do blocking writes directly to the socket, with no buffer in the middle. For RAM, only the migration_bitmap_sync() call needs the iothread lock. For block migration, it is needed by the block layer (including bdrv_drain_all and dirty bitmap access), but because some code is shared between iterate and complete, all of mig_save_device_dirty is run with the lock taken. In the savevm case, the iterate callback runs within the big lock. This is annoying because it complicates the rules. Luckily we do not need to do anything about it: the RAM iterate callback does not need the iothread lock, and block migration never runs during savevm. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: add lockPaolo Bonzini1-3/+51
Some state is shared between the block migration code and its AIO callbacks. Once block migration will run outside the iothread, the block migration code and the AIO callbacks will be able to run concurrently. Protect the critical sections with a separate lock. Do the same for completed_sectors, which can be used from the monitor. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: document usage of state across threadsPaolo Bonzini1-5/+18
Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: small preparatory changes for lockingPaolo Bonzini1-11/+15
Some small changes that will simplify the positioning of lock/unlock primitives. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: remove variables that are never readPaolo Bonzini1-13/+0
Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11block-migration: remove useless calls to blk_mig_cleanupPaolo Bonzini1-18/+8
Now that the cancel callback is called consistently for all errors, we can avoid doing its work in the other callbacks. Reviewed-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-02-12block-migration: fix pending() and iterate() return valuesStefan Hajnoczi1-9/+13
The return value of .save_live_pending() is the number of bytes remaining. This is just an estimate because we do not know how many blocks will be dirtied by the running guest. Currently our return value for .save_live_pending() is wrong because it includes dirty blocks but not in-flight bdrv_aio_readv() requests or unsent blocks. Crucially, it also doesn't include the bulk phase where the entire device is transferred - therefore we risk completing block migration before all blocks have been transferred! The return value of .save_live_iterate() is the number of bytes transferred this iteration. Currently we return whether there are bytes remaining, which is incorrect. Move the bytes remaining calculation into .save_live_pending() and really return the number of bytes transferred this iteration in .save_live_iterate(). Also fix the %ld format specifier which was used for a uint64_t argument. PRIu64 must be use to avoid warnings on 32-bit hosts. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-id: 1360661835-28663-3-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11block-migration: fix block_save_iterate() return valueStefan Hajnoczi1-1/+6
The .save_live_iterate() function returns 0 to continue iterating or 1 to stop iterating. Since 16310a3cca7320edb9341c976f7819de0a8c27e0 it only ever returns 0, leading to an infinite loop. Return 1 if we have finished sending dirty blocks. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1360534366-26723-4-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11block-migration: fix blk_mig_save_dirty_block() return value checkingStefan Hajnoczi1-2/+2
Commit 43be3a25c931a7f61a76fbfc9d35584cbfc5fb58 changed the blk_mig_save_dirty_block() return code handling. The function's doc comment says: /* return value: * 0: too much data for max_downtime * 1: few enough data for max_downtime */ Because of the 1 return value, callers must check for ret < 0 instead of just: if (ret) { ... } We do not want to bail when 1 is returned, only on error. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1360534366-26723-3-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11block-migration: improve "Unknown flags" error messageStefan Hajnoczi1-1/+1
Show the actual flags value and include "block migration" in the error message so it's clear where the error is coming from. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1360534366-26723-2-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-01-25block: allow customizing the granularity of the dirty bitmapPaolo Bonzini1-2/+3
Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-25block: return count of dirty sectors, not chunksPaolo Bonzini1-1/+1
Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-12-20savevm: New save live migration method: pendingJuan Quintela1-39/+10
Code just now does (simplified for clarity) if (qemu_savevm_state_iterate(s->file) == 1) { vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); qemu_savevm_state_complete(s->file); } Problem here is that qemu_savevm_state_iterate() returns 1 when it knows that remaining memory to sent takes less than max downtime. But this means that we could end spending 2x max_downtime, one downtime in qemu_savevm_iterate, and the other in qemu_savevm_state_complete. Changed code to: pending_size = qemu_savevm_state_pending(s->file, max_size); DPRINTF("pending size %lu max %lu\n", pending_size, max_size); if (pending_size >= max_size) { ret = qemu_savevm_state_iterate(s->file); } else { vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); qemu_savevm_state_complete(s->file); } So what we do is: at current network speed, we calculate the maximum number of bytes we can sent: max_size. Then we ask every save_live section how much they have pending. If they are less than max_size, we move to complete phase, otherwise we do an iterate one. This makes things much simpler, because now individual sections don't have to caluclate the bandwidth (it was implossible to do right from there). Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19softmmu: move include files to include/sysemu/Paolo Bonzini1-1/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19misc: move include files to include/qemu/Paolo Bonzini1-2/+2
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19migration: move include files to include/migration/Paolo Bonzini1-2/+2
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19block: move include files to include/block/Paolo Bonzini1-1/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-10-17block-migration: handle errors with the return codes correctlyJuan Quintela1-12/+14
Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-10-17block-migration: Switch meaning of return valueJuan Quintela1-5/+9
Make consistent the result of blk_mig_save_dirty_block() and mig_save_device_dirty() Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-10-17block-migration: make flush_blks() return errorsJuan Quintela1-14/+8
This means we don't need to pass through qemu_file to get the errors. Adjust all callers. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-09-28block-migration: Flush requests in blk_mig_cleanupKevin Wolf1-0/+2
When cancelling block migration, all in-flight requests of the block migration must be completed before the data can be freed. This was visible as failing assertions and segfaults. Reported-by: Peter Lieven <pl@dlhnet.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-07-20savevm: split save_live into stage2 and stage3Juan Quintela1-39/+60
We split it into 2 functions, foo_live_iterate, and foo_live_complete. At this point, we only remove the bits that are for the other stage, functionally this is equivalent to previous code. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: split save_live_setup from save_live_stateJuan Quintela1-7/+28
This patch splits stage 1 to its own function for both save_live users, ram and block. It is just a copy of the function, removing the parts of the other stages. Optimizations would came later. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: introduce is_active methodJuan Quintela1-7/+6
Enable the creation of a method to tell migration if that section is active and should be migrate. We use it for blk-migration, that is normally not active. We don't create the method for RAM, as setups without RAM are very strange O:-) Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: Refactor cancel operation in its own operationJuan Quintela1-4/+6
Intead of abusing stage with value -1. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-07-20savevm: Live migration handlers register the struct directlyJuan Quintela1-2/+8
Notice that the live migration users never unregister, so no problem about freeing the ops structure. Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-06-29Add MigrationParams structureIsaku Yamahata1-4/+4
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
2012-03-15Purge migration of (almost) everything to do with monitorsLuiz Capitulino1-33/+25
The Monitor object is passed back and forth within the migration/savevm code so that it can print errors and progress to the user. However, that approach assumes a HMP monitor, being completely invalid in QMP. This commit drops almost every single usage of the Monitor object, all monitor_printf() calls have been converted into DPRINTF() ones. There are a few remaining Monitor objects, those are going to be dropped by the next commit. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-01-13prepare for future GPLv2+ relicensingPaolo Bonzini1-0/+2
All files under GPLv2 will get GPLv2+ changes starting tomorrow. event_notifier.c and exec-obsolete.h were only ever touched by Red Hat employees and can be relicensed now. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-12-15block: bdrv_aio_* do not return NULLPaolo Bonzini1-13/+0
Initially done with the following semantic patch: @ rule1 @ expression E; statement S; @@ E = ( bdrv_aio_readv | bdrv_aio_writev | bdrv_aio_flush | bdrv_aio_discard | bdrv_aio_ioctl ) (...); ( - if (E == NULL) { ... } | - if (E) { <... S ...> } ) which however missed the occurrence in block/blkverify.c (as it should have done), and left behind some unused variables. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-12-05block: convert qemu_aio_flush() calls to bdrv_drain_all()Stefan Hajnoczi1-1/+1
Many places in QEMU call qemu_aio_flush() to complete all pending asynchronous I/O. Most of these places actually want to drain all block requests but there is no block layer API to do so. This patch introduces the bdrv_drain_all() API to wait for requests across all BlockDriverStates to complete. As a bonus we perform checks after qemu_aio_wait() to ensure that requests really have finished. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-17Fix some spelling bugs in documentation and commentsStefan Weil1-1/+1
These errors were detected by codespell: remaing -> remaining soley -> solely virutal -> virtual seperate -> separate libcacard.txt still needs some more patches. Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-10-20migration: make *save_live return errorsJuan Quintela1-6/+11
Make *save_live() return negative values when there is one error, and updates all callers to check for the error. Signed-off-by: Juan Quintela <quintela@redhat.com>