Commit Graph

121 Commits

Author SHA1 Message Date
Eric Blake
e24d813b29 block: Simplify bdrv_can_write_zeroes_with_unmap()
We don't need the can_write_zeroes_with_unmap field in
BlockDriverInfo, because it is redundant information with
supported_zero_flags & BDRV_REQ_MAY_UNMAP.  Note that
BlockDriverInfo and supported_zero_flags are both per-device
settings, rather than global state about the driver as a
whole, which means one or both of these bits of information
can already be conditional.  Let's audit how they were set:

crypto: always setting can_write_ to false is pointless (the
struct starts life zero-initialized), no use of supported_

nbd: just recently fixed to set can_write_ if supported_
includes MAY_UNMAP (thus this commit effectively reverts
bca80059e and solves the problem mentioned there in a more
global way)

file-posix, iscsi, qcow2: can_write_ is conditional, while
supported_ was unconditional; but passing MAY_UNMAP would
fail with ENOTSUP if the condition wasn't met

qed: can_write_ is unconditional, but pwrite_zeroes lacks
support for MAY_UNMAP and supported_ is not set. Perhaps
support can be added later (since it would be similar to
qcow2), but for now claiming false is no real loss

all other drivers: can_write_ is not set, and supported_ is
either unset or a passthrough

Simplify the code by moving the conditional into
supported_zero_flags for all drivers, then dropping the
now-unused BDI field.  For callers that relied on
bdrv_can_write_zeroes_with_unmap(), we return the same
per-device settings for drivers that had conditions (no
observable change in behavior there); and can now return
true (instead of false) for drivers that support passthrough
(for example, the commit driver) which gives those drivers
the same fix as nbd just got in bca80059e.  For callers that
relied on supported_zero_flags, we now have a few more places
that can avoid a wasted call to pwrite_zeroes() that will
just fail with ENOTSUP.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180126193439.20219-1-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-02-09 12:32:44 -06:00
Markus Armbruster
922a01a013 Move include qemu/option.h from qemu-common.h to actual users
qemu-common.h includes qemu/option.h, but most places that include the
former don't actually need the latter.  Drop the include, and add it
to the places that actually need it.

While there, drop superfluous includes of both headers, and
separate #include from file comment with a blank line.

This cleanup makes the number of objects depending on qemu/option.h
drop from 4545 (out of 4743) to 284 in my "build everything" tree.

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: <20180201111846.21846-20-armbru@redhat.com>
[Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
2018-02-09 13:52:16 +01:00
Markus Armbruster
bbcad965bf Drop superfluous includes of qapi/qmp/qjson.h
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: <20180201111846.21846-19-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Edgar Kaziakhmedov
9776f0db6a nbd: implement bdrv_get_info callback
Since mirror job supports efficient zero out target mechanism (see
in mirror_dirty_init()), implement bdrv_get_info to make it work
over NBD. Such improvement will allow using the largest chunk possible
and will decrease the number of NBD_CMD_WRITE_ZEROES requests on the wire.

Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Message-Id: <20180118115158.17219-1-edgar.kaziakhmedov@virtuozzo.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-01-26 09:58:46 -06:00
Murilo Opsfelder Araujo
c4365735a7 block/nbd: fix segmentation fault when .desc is not null-terminated
The find_desc_by_name() from util/qemu-option.c relies on the .name not being
NULL to call strcmp(). This check becomes unsafe when the list is not
NULL-terminated, which is the case of nbd_runtime_opts in block/nbd.c, and can
result in segmentation fault when strcmp() tries to access an invalid memory:

    #0 0x00007fff8c75f7d4 in __strcmp_power9 () from /lib64/libc.so.6
    #1 0x00000000102d3ec8 in find_desc_by_name (desc=0x1036d6f0, name=0x28e46670 "server.path") at util/qemu-option.c:166
    #2 0x00000000102d93e0 in qemu_opts_absorb_qdict (opts=0x28e47a80, qdict=0x28e469a0, errp=0x7fffec247c98) at util/qemu-option.c:1026
    #3 0x000000001012a2e4 in nbd_open (bs=0x28e42290, options=0x28e469a0, flags=24578, errp=0x7fffec247d80) at block/nbd.c:406
    #4 0x00000000100144e8 in bdrv_open_driver (bs=0x28e42290, drv=0x1036e070 <bdrv_nbd_unix>, node_name=0x0, options=0x28e469a0, open_flags=24578, errp=0x7fffec247f50) at block.c:1135
    #5 0x0000000010015b04 in bdrv_open_common (bs=0x28e42290, file=0x0, options=0x28e469a0, errp=0x7fffec247f50) at block.c:1395

>From gdb, the desc[i].name was not NULL and resulted in strcmp() accessing an
invalid memory:

    >>> p desc[5]
    $8 = {
      name = 0x1037f098 "R27A",
      type = 1561964883,
      help = 0xc0bbb23e <error: Cannot access memory at address 0xc0bbb23e>,
      def_value_str = 0x2 <error: Cannot access memory at address 0x2>
    }
    >>> p desc[6]
    $9 = {
      name = 0x103dac78 <__gcov0.do_qemu_init_bdrv_nbd_init> "\001",
      type = 272101528,
      help = 0x29ec0b754403e31f <error: Cannot access memory at address 0x29ec0b754403e31f>,
      def_value_str = 0x81f343b9 <error: Cannot access memory at address 0x81f343b9>
    }

This patch fixes the segmentation fault in strcmp() by adding a NULL element at
the end of nbd_runtime_opts.desc list, which is the common practice to most of
other structs like runtime_opts in block/null.c. Thus, the desc[i].name != NULL
check becomes safe because it will not evaluate to true when .desc list reached
its end.

Reported-by: R. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1727259
Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.vnet.ibm.com>
Message-Id: <20180105133241.14141-2-muriloo@linux.vnet.ibm.com>
CC: qemu-stable@nongnu.org
Fixes: 7ccc44fd7d
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-01-08 09:12:23 -06:00
Eric Blake
081dd1fe36 nbd: Implement NBD_INFO_BLOCK_SIZE on client
The upstream NBD Protocol has defined a new extension to allow
the server to advertise block sizes to the client, as well as
a way for the client to inform the server whether it intends to
obey block sizes.

When using the block layer as the client, we will obey block
sizes; but when used as 'qemu-nbd -c' to hand off to the
kernel nbd module as the client, we are still waiting for the
kernel to implement a way for us to learn if it will honor
block sizes (perhaps by an addition to sysfs, rather than an
ioctl), as well as any way to tell the kernel what additional
block sizes to obey (NBD_SET_BLKSIZE appears to be accurate
for the minimum size, but preferred and maximum sizes would
probably be new ioctl()s), so until then, we need to make our
request for block sizes conditional.

When using ioctl(NBD_SET_BLKSIZE) to hand off to the kernel,
use the minimum block size as the sector size if it is larger
than 512, which also has the nice effect of cooperating with
(non-qemu) servers that don't do read-modify-write when
exposing a block device with 4k sectors; it might also allow
us to visit a file larger than 2T on a 32-bit kernel.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170707203049.534-10-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 12:04:42 +02:00
Eric Blake
004a89fce9 nbd: Create struct for tracking export info
The NBD Protocol is introducing some additional information
about exports, such as minimum request size and alignment, as
well as an advertised maximum request size.  It will be easier
to feed this information back to the block layer if we gather
all the information into a struct, rather than adding yet more
pointer parameters during negotiation.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170707203049.534-2-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 12:04:41 +02:00
Max Reitz
f69165a8fe block: Do not strcmp() with NULL uri->scheme
uri_parse(...)->scheme may be NULL. In fact, probably every field may be
NULL, and the callers do test this for all of the other fields but not
for scheme (except for block/gluster.c; block/vxhs.c does not access
that field at all).

We can easily fix this by using g_strcmp0() instead of strcmp().

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170613205726.13544-1-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26 14:54:46 +02:00
Marc-André Lureau
01b2ffcedd qapi: merge QInt and QFloat in QNum
We would like to use a same QObject type to represent numbers, whether
they are int, uint, or floats. Getters will allow some compatibility
between the various types if the number fits other representations.

Add a few more tests while at it.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170607163635.17635-7-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[parse_stats_intervals() simplified a bit, comment in
test_visitor_in_int_overflow() tidied up, suppress bogus warnings]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-06-20 14:31:31 +02:00
Markus Armbruster
bd269ebc82 sockets: Limit SocketAddressLegacy to external interfaces
SocketAddressLegacy is a simple union, and simple unions are awkward:
they have their variant members wrapped in a "data" object on the
wire, and require additional indirections in C.  SocketAddress is the
equivalent flat union.  Convert all users of SocketAddressLegacy to
SocketAddress, except for existing external interfaces.

See also commit fce5d53..9445673 and 85a82e8..c5f1ae3.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-7-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Minor editing accident fixed, commit message and a comment tweaked]

Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-05-09 09:14:40 +02:00
Markus Armbruster
62cf396b5d sockets: Rename SocketAddressFlat to SocketAddress
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-6-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Prasanna Kumar Kalever <prasanna.kalever@redhat.com>
2017-05-09 09:14:40 +02:00
Markus Armbruster
dfd100f242 sockets: Rename SocketAddress to SocketAddressLegacy
The next commit will rename SocketAddressFlat to SocketAddress, and
the commit after that will replace most uses of SocketAddressLegacy by
SocketAddress, replacing most of this commit's renames right back.

Note that checkpatch emits a few "line over 80 characters" warnings.
The long lines are all temporary; the SocketAddressLegacy replacement
will shorten them again.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-5-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-05-09 09:14:40 +02:00
Markus Armbruster
0785bd7a7c sockets: Prepare inet_parse() for flattened SocketAddress
I'm going to flatten SocketAddress: rename SocketAddress to
SocketAddressLegacy, SocketAddressFlat to SocketAddress, eliminate
SocketAddressLegacy except in external interfaces.

inet_parse() returns a newly allocated InetSocketAddress.  Lift the
allocation from inet_parse() into its caller socket_parse() to prepare
for flattening SocketAddress.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-3-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Straightforward rebase]
2017-05-09 09:14:40 +02:00
Eric Blake
46f5ac205a qobject: Use simpler QDict/QList scalar insertion macros
We now have macros in place to make it less verbose to add a scalar
to QDict and QList, so use them.

Patch created mechanically via:
  spatch --sp-file scripts/coccinelle/qobject.cocci \
    --macro-file scripts/cocci-macro-file.h --dir . --in-place
then touched up manually to fix a couple of '?:' back to original
spacing, as well as avoiding a long line in monitor.c.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170427215821.19397-7-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-05-09 09:13:51 +02:00
Peter Maydell
87cc4c6102 * MemoryRegionCache revert
* glib optimization workaround
 * fix "info lapic" segfault on isapc
 * fix QIOChannel memory leak
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* MemoryRegionCache revert
* glib optimization workaround
* fix "info lapic" segfault on isapc
* fix QIOChannel memory leak

# gpg: Signature made Mon 03 Apr 2017 18:17:00 BST
# gpg:                using RSA key 0xBFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  main-loop: Acquire main_context lock around os_host_main_loop_wait.
  exec: revert MemoryRegionCache
  nbd: fix memory leak on socket_connect failed
  ipmi: Fix macro issues
  target-i386: fix "info lapic" segfault on isapc
  iscsi: drop unused IscsiAIOCB.qiov field

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-04-04 11:40:55 +01:00
Markus Armbruster
9445673ea6 nbd: Tidy up blockdev-add interface
SocketAddress is a simple union, and simple unions are awkward: they
have their variant members wrapped in a "data" object on the wire, and
require additional indirections in C.  I intend to limit its use to
existing external interfaces, and convert all internal interfaces to
SocketAddressFlat.

BlockdevOptionsNbd is an external interface using SocketAddress.  We
already use SocketAddressFlat elsewhere in blockdev-add.  Replace it
by SocketAddressFlat while we can (it's new in 2.9) for simplicity and
consistency.  For example,

    { "execute": "blockdev-add",
      "arguments": { "node-name": "foo", "driver": "nbd",
                     "server": { "type": "inet",
		                 "data": { "host": "localhost",
				           "port": "12345" } } } }

becomes

    { "execute": "blockdev-add",
      "arguments": { "node-name": "foo", "driver": "nbd",
                     "server": { "type": "inet",
		                 "host": "localhost", "port": "12345" } } }

Since the internal interfaces still take SocketAddress, this requires
conversion function socket_address_crumple().  It'll go away when I
update the interfaces.

Unfortunately, SocketAddress is also visible in -drive since 2.8:

    -drive if=none,driver=nbd,server.type=inet,server.data.host=127.0.0.1,server.data.port=12345

Nobody should be using it, as it's fairly new and has never been
documented, so adding still more compatibility gunk to keep it working
isn't worth the trouble.  You now have to use

    -drive if=none,driver=nbd,server.type=inet,server.host=127.0.0.1,server.port=12345

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1490895797-29094-9-git-send-email-armbru@redhat.com

[mreitz: Change iotest 147 accordingly]

Because of this interface change, iotest 147 has to be adapted.
Unfortunately, we cannot just flatten all of the addresses because
nbd-server-start still takes a plain SocketAddress. Therefore, we need
both and this is most easily achieved by writing the SocketAddress into
the code and flattening it where necessary.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170330221243.17333-1-mreitz@redhat.com

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
Markus Armbruster
129c7d1c53 block: Document -drive problematic code and bugs
-blockdev and blockdev_add convert their arguments via QObject to
BlockdevOptions for qmp_blockdev_add(), which converts them back to
QObject, then to a flattened QDict.  The QDict's members are typed
according to the QAPI schema.

-drive converts its argument via QemuOpts to a (flat) QDict.  This
QDict's members are all QString.

Thus, the QType of a flat QDict member depends on whether it comes
from -drive or -blockdev/blockdev_add, except when the QAPI type maps
to QString, which is the case for 'str' and enumeration types.

The block layer core extracts generic configuration from the flat
QDict, and the block driver extracts driver-specific configuration.

Both commonly do so by converting (parts of) the flat QDict to
QemuOpts, which turns all values into strings.  Not exactly elegant,
but correct.

However, A few places access the flat QDict directly:

* Most of them access members that are always QString.  Correct.

* bdrv_open_inherit() accesses a boolean, carefully.  Correct.

* nfs_config() uses a QObject input visitor.  Correct only because the
  visited type contains nothing but QStrings.

* nbd_config() and ssh_config() use a QObject input visitor, and the
  visited types contain non-QStrings: InetSocketAddress members
  @numeric, @to, @ipv4, @ipv6.  -drive works as long as you don't try
  to use them (they're all optional).  @to is ignored anyway.

  Reproducer:
  -drive driver=ssh,server.host=h,server.port=22,server.ipv4,path=p
  -drive driver=nbd,server.type=inet,server.data.host=h,server.data.port=22,server.data.ipv4
  both fail with "Invalid parameter type for 'data.ipv4', expected: boolean"

Add suitable comments to all these places.  Mark the buggy ones FIXME.

"Fortunately", -drive's driver-specific options are entirely
undocumented.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1490895797-29094-5-git-send-email-armbru@redhat.com
[mreitz: Fixed two typos]
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
Markus Armbruster
ca0b64e5ed nbd sockets vnc: Mark problematic address family tests TODO
Certain features make sense only with certain address families.  For
instance, passing file descriptors requires AF_UNIX.  Testing
SocketAddress's saddr->type == SOCKET_ADDRESS_KIND_UNIX is obvious,
but problematic: it can't recognize AF_UNIX when type ==
SOCKET_ADDRESS_KIND_FD.

Mark such tests of saddr->type TODO.  We may want to check the address
family with getsockname() there.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1490895797-29094-2-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
yaolujing
cc1e139139 nbd: fix memory leak on socket_connect failed
When TCP connection fails between nbd server and client,
the local var, sioc, memory leak.

This patch fixes the memory leak.

Signed-off-by: yaolujing <yaolujing@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1491005709-29989-1-git-send-email-yaolujing@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-02 21:18:21 +02:00
Stefan Hajnoczi
e4548bb640 nbd: drop unused NBDClientSession.is_unix field
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170327123223.1199-1-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-27 14:41:01 +02:00
Markus Armbruster
048abb7b20 qapi: Drop unused non-strict qobject input visitor
The split between tests/test-qobject-input-visitor.c and
tests/test-qobject-input-strict.c now makes less sense than ever.  The
next commit will take care of that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1488544368-30622-20-git-send-email-armbru@redhat.com>
2017-03-05 09:14:19 +01:00
Markus Armbruster
7c81e4e9db block: Don't bother asserting type of output visitor's output
After a visit of a complex QAPI type FOO

    ov = qobject_output_visitor_new(&foo);
    visit_type_FOO(ov, NULL, expr, &error_abort);
    visit_complete(ov, &foo);

we can safely assume qobject_type(foo) is QTYPE_QDICT.  We do in many
places, but occasionally assert qobject_type(obj) == QTYPE_QDICT.
Don't.  The appropriate place to check such fundamental properties of
QAPI visitors is the test suite.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487363905-9480-15-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-02-22 19:52:20 +01:00
Ashijeet Acharya
a1d4e38a8b block/nbd: Fix the leaked visitor
This patch frees the leaked visitor in nbd_refresh_filename() and uses
visit_free() to fix it. The leak was introduced by the commit 491d6c7.

Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-11-11 15:54:55 +01:00
Eric Blake
fa778fffdf nbd: Implement NBD_CMD_WRITE_ZEROES on client
Upstream NBD protocol recently added the ability to efficiently
write zeroes without having to send the zeroes over the wire,
along with a flag to control whether the client wants a hole.

The generic block code takes care of falling back to the obvious
write of lots of zeroes if we return -ENOTSUP because the server
does not have WRITE_ZEROES.

Ideally, since NBD_CMD_WRITE_ZEROES does not involve any data
over the wire, we want to support transactions that are much
larger than the normal 32M limit imposed on NBD_CMD_WRITE.  But
the server may still have a limit smaller than UINT_MAX, so
until experimental NBD protocol additions for advertising various
command sizes is finalized (see [1], [2]), for now we just stick to
the same limits as normal writes.

[1] https://github.com/yoe/nbd/blob/extension-info/doc/proto.md
[2] https://sourceforge.net/p/nbd/mailman/message/35081223/

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1476469998-28592-17-git-send-email-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-11-02 09:28:56 +01:00
Eric Blake
10676b81a9 nbd: Rename NbdClientSession to NBDClientSession
It's better to use consistent capitalization of the namespace
used for NBD functions; we have more instances of NBD* than
Nbd*.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1476469998-28592-5-git-send-email-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-11-02 09:28:55 +01:00
Peter Maydell
01b601f061 Merge qio 2016/10/27 v1
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Merge remote-tracking branch 'remotes/berrange/tags/pull-qio-2016-10-27-1' into staging

Merge qio 2016/10/27 v1

# gpg: Signature made Thu 27 Oct 2016 13:54:03 BST
# gpg:                using RSA key 0xBE86EBB415104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>"
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>"
# Primary key fingerprint: DAF3 A6FD B26B 6291 2D0E  8E3F BE86 EBB4 1510 4FDF

* remotes/berrange/tags/pull-qio-2016-10-27-1:
  main: set names for main loop sources created
  vnc: set name for all I/O channels created
  migration: set name for all I/O channels created
  char: set name for all I/O channels created
  nbd: set name for all I/O channels created
  io: add ability to set a name for IO channels
  io: Add a QIOChannelSocket cleanup test
  io: set LISTEN flag explicitly for listen sockets
  io: Introduce a qio_channel_set_feature() helper
  io: Use qio_channel_has_feature() where applicable
  io: Fix double shift usages on QIOChannel features

Conflicts:
	qemu-char.c

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-28 15:30:55 +01:00
Max Reitz
f84d431b86 block/nbd: Use SocketAddress options
Drop the use of legacy options in favor of the SocketAddress
representation, even for internal use (i.e. for storing the result of
the filename parsing).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-27 19:05:23 +02:00
Max Reitz
491d6c7c4e block/nbd: Accept SocketAddress
Add a new option "server" to the NBD block driver which accepts a
SocketAddress.

"path", "host" and "port" are still supported as legacy options and are
mapped to their corresponding SocketAddress representation.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-27 19:05:23 +02:00
Max Reitz
48c38e0b8d block/nbd: Add nbd_has_filename_options_conflict()
Right now, we have four possible options that conflict with specifying
an NBD filename, and a future patch will add another one ("address").
This future option is a nested QDict that is flattened at this point,
requiring us to test each option whether its key has an "address."
prefix. Therefore, we will then need to iterate through all options
(including the "export" option which was not covered so far).

Adding this iteration logic now will simplify adding the new option
later. A nice side effect is that the user will not receive a long list
of five options which are not supposed to be specified with a filename,
but we can actually print the problematic option.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-27 19:05:23 +02:00
Max Reitz
fcfcd8ffcc block/nbd: Use qdict_put()
Instead of inlining this nice macro (i.e. resorting to
qdict_put_obj(..., QOBJECT(...))), use it.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-27 19:05:23 +02:00
Max Reitz
7edca33804 block/nbd: Default port in nbd_refresh_filename()
Instead of not emitting the port in nbd_refresh_filename(), just set it
to the default if the user did not specify it. This makes the logic a
bit simpler.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-27 19:05:23 +02:00
Max Reitz
442045cbce block/nbd: Reject port parameter without host
Currently, a port that is passed along with a UNIX socket path is
silently ignored. That is not exactly ideal, it should be an error
instead.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-27 19:05:23 +02:00
Max Reitz
82d73014a9 block/nbd: Drop trailing "." in error messages
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-27 19:05:23 +02:00
Daniel P. Berrange
0d73f7253e nbd: set name for all I/O channels created
Ensure that all I/O channels created for NBD are given names
to distinguish their respective roles.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-10-27 09:13:10 +02:00
Max Reitz
03504d05f0 block/nbd: Store runtime option values
Store the runtime option values in the BDRVNBDState so they can later be
used in nbd_refresh_filename() without having to directly access the
options QDict which may contain values of non-string types.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-08-15 15:52:29 +02:00
Max Reitz
7ccc44fd7d block/nbd: Use QemuOpts for runtime options
Using QemuOpts will prevent qemu from crashing if the input options have
not been validated (which is the case when they are specified on the
command line or in a json: filename) and some have the wrong type.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-08-15 15:52:28 +02:00
Eric Blake
70c4fb2648 nbd: Convert to byte-based interface
The NBD protocol doesn't have any notion of sectors, so it is
a fairly easy conversion to use byte-based read and write.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1468624988-423-19-git-send-email-eblake@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20 14:24:25 +01:00
Eric Blake
447e57c3b0 nbd: Switch .bdrv_co_discard() to byte-based
Another step towards killing off sector-based block APIs.

While at it, call directly into nbd-client.c instead of having
a pointless trivial wrapper in nbd.c.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468624988-423-14-git-send-email-eblake@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20 14:24:25 +01:00
Eric Blake
fb1a6de14a nbd: Rely on block layer to break up large requests
Now that the block layer will honor max_transfer, we can simplify
our code to rely on that guarantee.

The readv code can call directly into nbd-client, just as the
writev code has done since commit 52a4650.

Interestingly enough, while qemu-io 'w 0 40m' splits into a 32M
and 8M transaction, 'w -z 0 40m' splits into two 16M and an 8M,
because the block layer caps the bounce buffer for writing zeroes
at 16M.  When we later introduce support for NBD_CMD_WRITE_ZEROES,
we can get a full 32M zero write (or larger, if the client and
server negotiate that write zeroes can use a larger size than
ordinary writes).

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: 1468607524-19021-5-git-send-email-eblake@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20 14:11:54 +01:00
Eric Blake
b9f7855a50 block: Switch discard length bounds to byte-based
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>
2016-07-05 16:46:25 +02:00
Eric Blake
5def6b80e1 block: Switch transfer length bounds to byte-based
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>
2016-07-05 16:46:25 +02:00
Eric Blake
202204717a nbd: Advertise realistic limits to block layer
We were basing the advertisement of maximum discard and transfer
length off of UINT32_MAX, but since the rest of the block layer
has signed int limits on a transaction, nothing could ever reach
that maximum, and we risk overflowing an int once things are
converted to byte-based rather than sector-based limits.  What's
more, we DO have a much smaller limit: both the current kernel
and qemu-nbd have a hard limit of 32M on a read or write
transaction, and while they may also permit up to a full 32 bits
on a discard transaction, the upstream NBD protocol is proposing
wording that without any explicit advertisement otherwise,
clients should limit ALL requests to the same limits as read and
write, even though the other requests do not actually require as
many bytes across the wire.  So the better limit to tell the
block layer is 32M for both values.

Behavior doesn't actually change with this patch (the block layer
is currently ignoring the max_transfer advertisements); but when
that problem is fixed in a later series, this patch will prevent
the exposure of a latent bug.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05 16:46:24 +02:00
Eric Blake
52a4650574 nbd: Simplify client FUA handling
Now that the block layer honors per-bds FUA support, we don't
have to duplicate the fallback flush at the NBD layer.  The
static function nbd_co_writev_flags() is no longer needed, and
the driver can just directly use nbd_client_co_writev().

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>
2016-05-12 15:22:09 +02:00
Eric Blake
4df863f336 block: Make supported_write_flags a per-bds property
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>
2016-05-12 15:22:09 +02:00
Kevin Wolf
78a07294d5 block: Introduce bdrv_driver_pwritev()
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>
2016-05-12 15:22:07 +02:00
Kevin Wolf
2b556518c3 nbd: Support BDRV_REQ_FUA
The NBD server already used to send a FUA flag when the writethrough
mode was set. This code was a remnant from the times where protocol
drivers actually had to implement writethrough modes. Since nowadays the
block layer sends flushes in writethrough mode and non-root nodes are
always writeback, this was mostly dead code - only mostly because if NBD
was configured to be used without a format, we sent _both_ FUA and an
explicit flush afterwards, which makes the code not technically dead,
but useless overhead.

This patch changes the code so that the block layer's FUA flag is
recognised and translated into a NBD FUA flag. The additional flush is
avoided now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30 12:16:02 +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
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Eric Blake
32bafa8fdd qapi: Don't special-case simple union wrappers
Simple unions were carrying a special case that hid their 'data'
QMP member from the resulting C struct, via the hack method
QAPISchemaObjectTypeVariant.simple_union_type().  But by using
the work we started by unboxing flat union and alternate
branches, coupled with the ability to visit the members of an
implicit type, we can now expose the simple union's implicit
type in qapi-types.h:

| struct q_obj_ImageInfoSpecificQCow2_wrapper {
|     ImageInfoSpecificQCow2 *data;
| };
|
| struct q_obj_ImageInfoSpecificVmdk_wrapper {
|     ImageInfoSpecificVmdk *data;
| };
...
| struct ImageInfoSpecific {
|     ImageInfoSpecificKind type;
|     union { /* union tag is @type */
|         void *data;
|-        ImageInfoSpecificQCow2 *qcow2;
|-        ImageInfoSpecificVmdk *vmdk;
|+        q_obj_ImageInfoSpecificQCow2_wrapper qcow2;
|+        q_obj_ImageInfoSpecificVmdk_wrapper vmdk;
|     } u;
| };

Doing this removes asymmetry between QAPI's QMP side and its
C side (both sides now expose 'data'), and means that the
treatment of a simple union as sugar for a flat union is now
equivalent in both languages (previously the two approaches used
a different layer of dereferencing, where the simple union could
be converted to a flat union with equivalent C layout but
different {} on the wire, or to an equivalent QMP wire form
but with different C representation).  Using the implicit type
also lets us get rid of the simple_union_type() hack.

Of course, now all clients of simple unions have to adjust from
using su->u.member to using su->u.member.data; while this touches
a number of files in the tree, some earlier cleanup patches
helped minimize the change to the initialization of a temporary
variable rather than every single member access.  The generated
qapi-visit.c code is also affected by the layout change:

|@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member
|     }
|     switch (obj->type) {
|     case IMAGE_INFO_SPECIFIC_KIND_QCOW2:
|-        visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err);
|+        visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err);
|         break;
|     case IMAGE_INFO_SPECIFIC_KIND_VMDK:
|-        visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err);
|+        visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err);
|         break;
|     default:
|         abort();

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-18 10:29:26 +01:00
Eric Blake
0399293e5b util: Shorten references into SocketAddress
An upcoming patch will alter how simple unions, like SocketAddress,
are laid out, which will impact all lines of the form 'addr->u.XXX'
(expanding it to the longer 'addr->u.XXX.data').  For better
legibility in that patch, and less need for line wrapping, it's better
to use a temporary variable to reduce the effect of a layout change to
just the variable initializations, rather than every reference within
a SocketAddress.  Also, take advantage of some C99 initialization where
it makes sense (simplifying g_new0() to g_new()).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457021813-10704-7-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-05 10:41:52 +01:00