Commit Graph

81 Commits

Author SHA1 Message Date
Yasmin Beatriz
0c33659d09 dump.c: allow fd_write_vmcore to return errno on failure
fd_write_vmcore can fail to execute for a lot of reasons that can be
retrieved by errno, but it only returns -1. This makes difficult for
the caller to know what happened and only a generic error message is
propagated back to the user. This is an example using dump-guest-memory:

(qemu) dump-guest-memory /home/yasmin/mnt/test.dump
dump: failed to save memory

All callers of fd_write_vmcore of dump.c does error handling via
error_setg(), so at first it seems feasible to add the Error pointer as
an argument of fd_write_vmcore. This proved to be more complex than it
first looked. fd_write_vmcore is used by write_elf64_notes and
write_elf32_notes as a WriteCoreDumpFunction prototype. WriteCoreDumpFunction
is declared in include/qom/cpu.h and is used all around the code. This
leaves us with few alternatives:

- change the WriteCoreDumpFunction prototype to include an error pointer.
This would require to change all functions that implements this prototype
to also receive an Error pointer;

- change both write_elf64_notes and write_elf32_notes to no use the
WriteCoreDumpFunction. These functions use not only fd_write_vmcore
but also buf_write_note, so this would require to change buf_write_note
to handle an Error pointer. Considerable easier than the alternative
above, but it's still a lot of code just for the benefit of the callers
of fd_write_vmcore.

This patch presents an easier solution that benefits all fd_write_vmcore
callers:

- instead of returning -1 on error, return -errno. All existing callers
already checks for ret < 0 so there is no need to change the caller's
logic too much. This also allows the retrieval of the errno.

- all callers were updated to use error_setg_errno instead of just
errno_setg. Now that fd_write_vmcore can return an errno, let's update
all callers so they can benefit from a more detailed error message.

This is the same dump-guest-memory example with this patch applied:

(qemu) dump-guest-memory /home/yasmin/mnt/test.dump
dump: failed to save memory: No space left on device
(qemu)

This example illustrates an error of fd_write_vmcore when called
from write_data. All other callers will benefit from better
error messages as well.

Reported-by: yilzhang@redhat.com
Cc: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Yasmin Beatriz <yasmins@linux.vnet.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Message-Id: <20180212142506.28445-2-danielhb@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2018-03-21 14:55:49 +01:00
Wei Huang
68cbecfdd7 dump: Update correct kdump phys_base field for AArch64
For guest kernel that supports KASLR, the load address can change every
time when guest VM runs. To find the physical base address correctly,
current QEMU dump searches VMCOREINFO for the string "NUMBER(phys_base)=".
However this string pattern is only available on x86_64. AArch64 uses a
different field, called "NUMBER(PHYS_OFFSET)=". This patch makes sure
QEMU dump uses the correct string on AArch64.

Signed-off-by: Wei Huang <wei@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 1520615003-20869-1-git-send-email-wei@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-19 18:23:24 +00:00
Markus Armbruster
112ed241f5 qapi: Empty out qapi-schema.json
The previous commit improved compile time by including less of the
generated QAPI headers.  This is impossible for stuff defined directly
in qapi-schema.json, because that ends up in headers that that pull in
everything.

Move everything but include directives from qapi-schema.json to new
sub-module qapi/misc.json, then include just the "misc" shard where
possible.

It's possible everywhere, except:

* monitor.c needs qmp-command.h to get qmp_init_marshal()

* monitor.c, ui/vnc.c and the generated qapi-event-FOO.c need
  qapi-event.h to get enum QAPIEvent

Perhaps we'll get rid of those some other day.

Adding a type to qapi/migration.json now recompiles some 120 instead
of 2300 out of 5100 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-25-armbru@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-02 13:45:50 -06:00
Markus Armbruster
e688df6bc4 Include qapi/error.h exactly where needed
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.

While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
2018-02-09 13:50:17 +01:00
Marc-André Lureau
c983ca8457 dump: fix note_name_equal()
Use the function argument "name" instead of hardcoded
"VMCOREINFO". All callers use "VMCOREINFO" as argument, so this isn't
an exposed bug, thankfully.

Simplify a little bit the code while touching this.

Suggested-by: Andrew Jones <drjones@redhat.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2018-01-02 14:49:54 +01:00
Marc-André Lureau
9ada575bba kdump: set vmcoreinfo location
kdump header provides offset and size of the vmcoreinfo content,
append it if available (skip the ELF note header).

crash-7.1.9 was the first version that started looking in the
vmcoreinfo data for phys_base instead of in the kdump_sub_header.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-10-15 05:54:40 +03:00
Marc-André Lureau
d9feb51772 dump: update phys_base header field based on VMCOREINFO content
If the guest note is VMCOREINFO, try to get phys_base from it.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-10-15 05:54:40 +03:00
Marc-André Lureau
903ef73496 dump: add guest ELF note
Read the guest ELF PT_NOTE from guest memory when fw_cfg
etc/vmcoreinfo entry provides the location, and write it as an
additional note in the dump.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-10-15 05:54:40 +03:00
David Hildenbrand
7f579e272f exec,dump,i386,ppc,s390x: don't include exec/cpu-all.h explicitly
All but a handful of files include exec/cpu-all.h via cpu.h only.
As these files already include cpu.h, let's just drop the additional
include.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-2-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-09-19 18:21:33 +02:00
Cornelia Huck
d1e6994abc dump: do not dump non-existent guest memory
It does not really make sense to dump memory that is not there.

Moreover, that fixes a segmentation fault when calling dump-guest-memory
with no filter for a machine with no memory defined.

New behaviour is:

(qemu) dump-guest-memory /dev/null
dump: no guest memory to dump
(qemu) dump-guest-memory /dev/null 0 4096
dump: no guest memory to dump

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20170913142036.2469-4-lvivier@redhat.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-09-14 15:52:10 +01:00
Alberto Garcia
c3a8fe331e misc: Remove unused Error variables
There's a few cases which we're passing an Error pointer to a function
only to discard it immediately afterwards without checking it. In
these cases we can simply remove the variable and pass NULL instead.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170829120836.16091-1-berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-30 11:58:26 +01:00
Fam Zheng
6796b4008b dump: Acquire BQL around vm_start() in dump thread
This fixes an assertion failure in the following backtrace:

    __GI___assert_fail
    memory_region_transaction_commit
    memory_region_add_eventfd
    virtio_pci_ioeventfd_assign
    virtio_bus_set_host_notifier
    virtio_blk_data_plane_start
    virtio_bus_start_ioeventfd
    virtio_vmstate_change
    vm_state_notify
    vm_prepare_start
    vm_start
    dump_cleanup
    dump_process
    dump_thread
    start_thread
    clone

vm_start need BQL, acquire it if doing cleaning up from main thread.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170503072819.14462-1-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-05 12:10:00 +02:00
Eduardo Habkost
621ff94d50 error: Remove NULL checks on error_propagate() calls
error_propagate() already ignores local_err==NULL, so there's no
need to check it before calling.

Coccinelle patch used to perform the changes added to
scripts/coccinelle/error_propagate_null.cocci.

Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1465855078-19435-2-git-send-email-ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-06-20 16:38:13 +02:00
Veronia Bahaa
f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Peter Xu
d42a0d1484 dump-guest-memory: add qmp event DUMP_COMPLETED
One new QMP event DUMP_COMPLETED is added. When a dump finishes, one
DUMP_COMPLETED event will occur to notify the user.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by:   Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-12-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:29 +01:00
Peter Xu
39ba2ea61f Dump: add qmp command "query-dump"
When dump-guest-memory is requested with detach flag, after its
return, user could query its status using "query-dump" command (with
no argument). The result contains:

- status: current dump status
- completed: bytes written in the latest dump
- total: bytes to write in the latest dump

From completed and total, we could know how much work
finished by calculating:

  100.0 * completed / total (%)

Reviewed-by:   Fam Zheng <famz@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1455772616-8668-10-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
2264c2c96e DumpState: adding total_size and written_size fields
Here, total_size is the size in bytes to be dumped (raw data, which
means before compression), while written_size are bytes handled (raw
size too).

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1455772616-8668-9-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
1fbeff72c2 dump-guest-memory: add "detach" support
If "detach" is provided, one thread is created to do the dump work,
while main thread will return immediately. For each GuestPhysBlock,
adding one more field "mr" to points to MemoryRegion that it
belongs, also ref the mr before use.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-8-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
63e27f28f2 dump-guest-memory: disable dump when in INMIGRATE state
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-7-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
ca1fc8c97e dump-guest-memory: introduce dump_process() helper function.
No functional change. Cleanup only.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-6-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
65d64f3623 dump-guest-memory: add dump_in_progress() helper function
For now, it has no effect. It will be used in dump detach support.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-5-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
baf28f57e2 dump-guest-memory: using static DumpState, add DumpStatus
Instead of malloc/free each time for DumpState, make it
static. Added DumpStatus to show status for dump.

This is to be used for detached dump.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-4-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
228de9cf1d dump-guest-memory: add "detach" flag for QMP/HMP interfaces.
This patch only adds the interfaces, but does not implement them.
"detach" parameter is made optional, to make sure that all the old
dump-guest-memory requests will still be able to work.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-3-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Xu
e3517a5299 dump-guest-memory: cleanup: removing dump_{error|cleanup}().
It might be a little bit confusing and error prone to do
dump_cleanup() in these two functions. A better way is to do
dump_cleanup() before dump finish, no matter whether dump has
succeeded or not.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-2-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:28 +01:00
Peter Maydell
d38ea87ac5 all: Clean up includes
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>
Message-id: 1454089805-5470-16-git-send-email-peter.maydell@linaro.org
2016-02-04 17:41:30 +00:00
Andrew Jones
b6e05aa473 dump: allow target to set the physical base
crash assumes the physical base in the kdump subheader of
makedumpfile formatted dumps is correct. Zero is not correct
for all architectures, so allow it to be changed.

(No functional change.)

Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-5-git-send-email-drjones@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-01-15 14:40:25 +00:00
Andrew Jones
8161befdd1 dump: allow target to set the page size
This is necessary for targets that don't have TARGET_PAGE_SIZE ==
real-target-page-size. The target should set the page size to the
correct one, if known, or, if not known, to the maximum page size
it supports.

(No functional change.)

Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-4-git-send-email-drjones@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-01-15 14:40:25 +00:00
Markus Armbruster
cc7a8ea740 Include qapi/qmp/qerror.h exactly where needed
In particular, don't include it into headers.

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>
2015-06-22 18:20:41 +02:00
Markus Armbruster
c6bd8c706a qerror: Clean up QERR_ macros to expand into a single string
These macros expand into error class enumeration constant, comma,
string.  Unclean.  Has been that way since commit 13f59ae.

The error class is always ERROR_CLASS_GENERIC_ERROR since the previous
commit.

Clean up as follows:

* Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and
  delete it from the QERR_ macro.  No change after preprocessing.

* Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into
  error_setg(...).  Again, no change after preprocessing.

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>
2015-06-22 18:20:40 +02:00
Gonglei
08a655be71 dump: Fix dump-guest-memory termination and use-after-close
dump_iterate() dumps blocks in a loop.  Eventually, get_next_block()
returns "no more".  We then call dump_completed().  But we neglect to
break the loop!  Broken in commit 4c7e251a.

Because of that, we dump the last block again.  This attempts to write
to s->fd, which fails if we're lucky.  The error makes dump_iterate()
return failure.  It's the only way it can ever return.

Theoretical: if we're not so lucky, something else has opened something
for writing and got the same fd.  dump_iterate() then keeps looping,
messing up the something else's output, until a write fails, or the
process mercifully terminates.

The obvious fix is to restore the return lost in commit 4c7e251a.  But
the root cause of the bug is needlessly opaque loop control.  Replace it
by a clean do ... while loop.

This makes the badly chosen return values of get_next_block() more
visible.  Cleaning that up is outside the scope of this bug fix.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-11-02 10:04:34 +03:00
zhanghailiang
4c7e251ae6 dump: Turn some functions to void to make code cleaner
Functions shouldn't return an error code and an Error object at the same time.
Turn all these functions that returning Error object to void.
We also judge if a function success or fail by reference to the local_err.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-10-23 09:01:29 -04:00
zhanghailiang
37917da2d0 dump: Propagate errors into qmp_dump_guest_memory()
The code calls dump_error() on error, and even passes it a suitable
message.  However, the message is thrown away, and its callers pass
up only success/failure.  All qmp_dump_guest_memory() can do is set
a generic error.

Propagate the errors properly, so qmp_dump_guest_memory() can return
a more useful error.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-10-23 09:01:29 -04:00
Chen Gang
2928207ac1 dump.c: Fix memory leak issue in cleanup processing for dump_init()
In dump_init(), when failure occurs, need notice about 'fd' and memory
mapping. So call dump_cleanup() for it (need let all initializations at
front).

Also simplify dump_cleanup(): remove redundant 'ret' and redundant 'fd'
checking.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-08-18 14:39:10 -04:00
Bharata B Rao
acb0ef5801 dump: Make DumpState and endian conversion routines available for arch-specific dump code
Make DumpState and endian conversion routines available for arch-specific dump
code by moving into dump.h. DumpState will be needed by arch-specific dump
code to access target endian information from DumpState->ArchDumpInfo. Also
break the dependency of dump.h from stubs/dump.c by creating a separate
dump-arch.h.

This patch doesn't change any functionality.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
[ rebased on top of current master branch,
  renamed endian helpers to cpu_to_dump{16,32,64},
  pass a DumpState * argument to endian helpers,
  Greg Kurz <gkurz@linux.vnet.ibm.com> ]
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
[agraf: fix to apply]
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-16 13:24:36 +02:00
Laszlo Ersek
b87ef3518b dump: simplify get_len_buf_out()
We can (and should) rely on the fact that s->flag_compress is exactly one
of DUMP_DH_COMPRESSED_ZLIB, DUMP_DH_COMPRESSED_LZO, and
DUMP_DH_COMPRESSED_SNAPPY.

This is ensured by the QMP schema and dump_init() in combination.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-11 10:10:28 -04:00
Laszlo Ersek
c998acb03d dump: hoist lzo_init() from get_len_buf_out() to dump_init()
qmp_dump_guest_memory()
  dump_init()
    lzo_init() <---------+
  create_kdump_vmcore()  |
    write_dump_pages()   |
      get_len_buf_out()  |
        lzo_init() ------+

This patch doesn't change the fact that lzo_init() is called for every
LZO-compressed dump, but it makes get_len_buf_out() more focused (single
responsibility).

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-11 10:10:28 -04:00
Laszlo Ersek
24aeeace7a dump: select header bitness based on ELF class, not ELF architecture
The specific ELF architecture (d_machine) carries Too Much Information
(TM) for deciding between create_header32() and create_header64(), use
"d_class" instead (ELFCLASS32 vs. ELFCLASS64).

This change adapts write_dump_header() to write_elf_loads(), dump_begin()
etc. that also rely on the ELF class of the target for bitness selection.

Considering the current targets that support dumping, cpu_get_dump_info()
works as follows:
- target-s390x/arch_dump.c: (EM_S390, ELFCLASS64) only
- target-ppc/arch_dump.c (EM_PPC64, ELFCLASS64) only
- target-i386/arch_dump.c: sets (EM_X86_64, ELFCLASS64) vs. (EM_386,
  ELFCLASS32) keying off the same Long Mode Active flag.

Hence no observable change.

Approximately-suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-11 10:10:28 -04:00
Laszlo Ersek
2f859f80c2 dump: eliminate DumpState.page_size ("guest's page size")
Use TARGET_PAGE_SIZE and ~TARGET_PAGE_MASK instead.

"DumpState.page_size" has type "size_t", whereas TARGET_PAGE_SIZE has type
"int". TARGET_PAGE_MASK is of type "int" and has negative value. The patch
affects the implicit type conversions as follows:

- create_header32() and create_header64(): assigned to "block_size", which
  has type "uint32_t". No change.

- get_next_page(): "block->target_start", "block->target_end" and "addr"
  have type "hwaddr" (uint64_t).

  Before the patch,
  - if "size_t" was "uint64_t", then no additional conversion was done as
    part of the usual arithmetic conversions,
  - If "size_t" was "uint32_t", then it was widened to uint64_t as part of
    the usual arithmetic conversions,
  for the remainder and addition operators.

  After the patch,
  - "~TARGET_PAGE_MASK" expands to  ~~((1 << TARGET_PAGE_BITS) - 1). It
    has type "int" and positive value (only least significant bits set).
    That's converted (widened) to "uint64_t" for the bit-ands. No visible
    change.
  - The same holds for the (addr + TARGET_PAGE_SIZE) addition.

- write_dump_pages():
  - TARGET_PAGE_SIZE passed as argument to a bunch of functions that all
    have prototypes. No change.

  - When incrementing "offset_data" (of type "off_t"): given that we never
    build for ILP32_OFF32 (see "-D_FILE_OFFSET_BITS=64" in configure),
    "off_t" is always "int64_t", and we only need to consider:
    - ILP32_OFFBIG: "size_t" is "uint32_t".
      - before: int64_t += uint32_t. Page size converted to int64_t for
        the addition.
      - after:  int64_t += int32_t. No change.
    - LP64_OFF64: "size_t" is "uint64_t".
      - before: int64_t += uint64_t. Offset converted to uint64_t for the
        addition, then the uint64_t result is converted to int64_t for
        storage.
      - after:  int64_t += int32_t. Same as the ILP32_OFFBIG/after case.
        No visible change.

  - (size_out < s->page_size) comparisons, and (size_out = s->page_size)
    assignment:
    - before: "size_out" is of type "size_t", no implicit conversion for
              either operator.
    - after: TARGET_PAGE_SIZE (of type "int" and positive value) is
             converted to "size_t" (for the relop because the latter is
             one of "uint32_t" and "uint64_t"). No visible change.

- dump_init():
  - DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), s->page_size): The
    innermost "DumpState.max_mapnr" field has type uint64_t, which
    propagates through all implicit conversions at hand:

    #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))

    regardless of the page size macro argument's type. In the outer macro
    replacement, the page size is converted from uint32_t and int32_t
    alike to uint64_t.

  - (tmp * s->page_size) multiplication: "tmp" has size "uint64_t"; the
    RHS is converted to that type from uint32_t and int32_t just the same
    if it's not uint64_t to begin with.

Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-11 10:10:28 -04:00
Laszlo Ersek
22227f121b dump: eliminate DumpState.page_shift ("guest's page shift")
Just use TARGET_PAGE_BITS.

"DumpState.page_shift" used to have type "uint32_t", while the replacement
TARGET_PAGE_BITS has type "int". Since "DumpState.page_shift" was only
used as bit shift counts in the paddr_to_pfn() and pfn_to_paddr() macros,
this is safe.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-11 10:10:28 -04:00
Laszlo Ersek
92ba1401e0 dump: simplify write_start_flat_header()
Currently, the function
- defines and populates an auto variable of type MakedumpfileHeader
- allocates and zeroes a buffer of size MAX_SIZE_MDF_HEADER (4096)
- copies the former into the latter (covering an initial portion of the
  latter)

Fill in the MakedumpfileHeader structure in its final place (the alignment
is OK because the structure lives at the address returned by g_malloc0()).

Approximately-suggested-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-11 10:10:28 -04:00
Laszlo Ersek
ae3f88f60f dump: fill in the flat header signature more pleasingly to the eye
The "mh.signature" array field has size 16, and is zeroed by the preceding
memset(). MAKEDUMPFILE_SIGNATURE expands to a string literal with string
length 12 (size 13). There's no need to measure the length of
MAKEDUMPFILE_SIGNATURE at runtime, nor for the extra zero-filling of
"mh.signature" with strncpy().

Use memcpy() with MIN(sizeof, sizeof) for robustness (which is an integer
constant expression, evaluable at compile time.)

Approximately-suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-11 10:10:28 -04:00
Markus Armbruster
66ef8bd9c1 dump: Drop pointless error_is_set(), DumpState member errp
In qmp_dump_guest_memory(), the error must be clear on entry, and we
always bail out after setting it, directly or via dump_init().
Therefore, both error_is_set() are always false.  Drop them.

DumpState member errp is now write-only.  Drop it, too.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-05-09 09:11:32 -04:00
qiaonuohan
7d6dc7f30c dump: add 'query-dump-guest-memory-capability' command
'query-dump-guest-memory-capability' is used to query the available formats for
'dump-guest-memory'. The output of the command will be like:

-> { "execute": "query-dump-guest-memory-capability" }
<- { "return": { "formats":
                    ["elf", "kdump-zlib", "kdump-lzo", "kdump-snappy"] }

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00
qiaonuohan
4ab23a9182 Define the architecture for compressed dump format
Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00
qiaonuohan
b53ccc30c4 dump: make kdump-compressed format available for 'dump-guest-memory'
Make monitor command 'dump-guest-memory' be able to dump in kdump-compressed
format. The command's usage:

  dump [-p] protocol [begin] [length] [format]

'format' is used to specified the format of vmcore and can be:
1. 'elf': ELF format, without compression
2. 'kdump-zlib': kdump-compressed format, with zlib-compressed
3. 'kdump-lzo': kdump-compressed format, with lzo-compressed
4. 'kdump-snappy': kdump-compressed format, with snappy-compressed
Without 'format' being set, it is same as 'elf'. And if non-elf format is
specified, paging and filter is not allowed.

Note:
  1. The kdump-compressed format is readable only with the crash utility and
     makedumpfile, and it can be smaller than the ELF format because of the
     compression support.
  2. The kdump-compressed format is the 6th edition.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00
qiaonuohan
d12f57ec66 dump: add API to write dump pages
functions are used to write page to vmcore. vmcore is written page by page.
page desc is used to store the information of a page, including a page's size,
offset, compression format, etc.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00
qiaonuohan
64cfba6a47 dump: add APIs to operate DataCache
DataCache is used to store data temporarily, then the data will be written to
vmcore. These functions will be called later when writing data of page to
vmcore.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00
qiaonuohan
d0686c7291 dump: add API to write dump_bitmap
functions are used to write 1st and 2nd dump_bitmap of kdump-compressed format,
which is used to indicate whether the corresponded page is existed in vmcore.
1st and 2nd dump_bitmap are same, because dump level is specified to 1 here.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00
qiaonuohan
298f116827 dump: add API to write dump header
the functions are used to write header of kdump-compressed format to vmcore.
Header of kdump-compressed format includes:
1. common header: DiskDumpHeader32 / DiskDumpHeader64
2. sub header: KdumpSubHeader32 / KdumpSubHeader64
3. extra information: only elf notes here

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00
qiaonuohan
7aad248d35 dump: add members to DumpState and init some of them
add some members to DumpState that will be used in writing vmcore in
kdump-compressed format. some of them, like page_size, will be initialized
in the patch.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-28 11:52:03 -05:00