Commit Graph

130 Commits

Author SHA1 Message Date
Emanuele Giuseppe Esposito
82618d7bc3 block: Convert bdrv_get_allocated_file_size() to co_wrapper
bdrv_get_allocated_file_size() is categorized as an I/O function, and it
currently doesn't run in a coroutine. We should let it take a graph
rdlock since it traverses the block nodes graph, which however is only
possible in a coroutine.

Therefore turn it into a co_wrapper to move the actual function into a
coroutine where the lock can be taken.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230113204212.359076-10-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01 16:52:32 +01:00
Emanuele Giuseppe Esposito
c86422c554 block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixed
BlockDriver->bdrv_getlength is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph
rdlock since the callback traverses the block nodes graph, which however
is only possible in a coroutine.

Therefore turn it into a co_wrapper to move the actual function into a
coroutine where the lock can be taken.

Because now this function creates a new coroutine and polls, we need to
take the AioContext lock where it is missing, for the only reason that
internally co_wrapper calls AIO_WAIT_WHILE and it expects to release the
AioContext lock.

This is especially messy when a co_wrapper creates a coroutine and polls
in bdrv_open_driver, because this function has so many callers in so
many context that it can easily lead to deadlocks. Therefore the new
rule for bdrv_open_driver is that the caller must always hold the
AioContext lock of the given bs (except if it is a coroutine), because
the function calls bdrv_refresh_total_sectors() which is now a
co_wrapper.

Once the rwlock is ultimated and placed in every place it needs to be,
we will poll using AIO_WAIT_WHILE_UNLOCKED and remove the AioContext
lock.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230113204212.359076-7-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01 16:52:32 +01:00
Markus Armbruster
e2c1c34f13 include/block: Untangle inclusion loops
We have two inclusion loops:

       block/block.h
    -> block/block-global-state.h
    -> block/block-common.h
    -> block/blockjob.h
    -> block/block.h

       block/block.h
    -> block/block-io.h
    -> block/block-common.h
    -> block/blockjob.h
    -> block/block.h

I believe these go back to Emanuele's reorganization of the block API,
merged a few months ago in commit d7e2fe4aac.

Fortunately, breaking them is merely a matter of deleting unnecessary
includes from headers, and adding them back in places where they are
now missing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221221133551.3967339-2-armbru@redhat.com>
2023-01-20 07:24:28 +01:00
Markus Armbruster
54fde4ff06 qapi block: Elide redundant has_FOO in generated C
The has_FOO for pointer-valued FOO are redundant, except for arrays.
They are also a nuisance to work with.  Recent commit "qapi: Start to
elide redundant has_FOO in generated C" provided the means to elide
them step by step.  This is the step for qapi/block*.json.

Said commit explains the transformation in more detail.

There is one instance of the invariant violation mentioned there:
qcow2_signal_corruption() passes false, "" when node_name is an empty
string.  Take care to pass NULL then.

The previous two commits cleaned up two more.

Additionally, helper bdrv_latency_histogram_stats() loses its output
parameters and returns a value instead.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Hanna Reitz <hreitz@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221104160712.3005652-11-armbru@redhat.com>
[Fixes for #ifndef LIBRBD_SUPPORTS_ENCRYPTION and MacOS squashed in]
2022-12-14 20:03:25 +01:00
Stefan Hajnoczi
e8b6535533 block: add BDRV_REQ_REGISTERED_BUF request flag
Block drivers may optimize I/O requests accessing buffers previously
registered with bdrv_register_buf(). Checking whether all elements of a
request's QEMUIOVector are within previously registered buffers is
expensive, so we need a hint from the user to avoid costly checks.

Add a BDRV_REQ_REGISTERED_BUF request flag to indicate that all
QEMUIOVector elements in an I/O request are known to be within
previously registered buffers.

Always pass the flag through to driver read/write functions. There is
little harm in passing the flag to a driver that does not use it.
Passing the flag to drivers avoids changes across many block drivers.
Filter drivers would need to explicitly support the flag and pass
through to their children when the children support it. That's a lot of
code changes and it's hard to remember to do that everywhere, leading to
silent reduced performance when the flag is accidentally dropped.

The only problematic scenario with the approach in this patch is when a
driver passes the flag through to internal I/O requests that don't use
the same I/O buffer. In that case the hint may be set when it should
actually be clear. This is a rare case though so the risk is low.

Some drivers have assert(!flags), which no longer works when
BDRV_REQ_REGISTERED_BUF is passed in. These assertions aren't very
useful anyway since the functions are called almost exclusively by
bdrv_driver_preadv/pwritev() so if we get flags handling right there
then the assertion is not needed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20221013185908.1297568-7-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-26 14:56:42 -04:00
Stefan Hajnoczi
9a891a91a1 gluster: stop using .bdrv_needs_filename
The gluster protocol driver used to parse URIs (filenames) but was
extended with a richer JSON syntax in commit 6c7189bb29
("block/gluster: add support for multiple gluster servers"). The gluster
drivers that have JSON parsing set .bdrv_needs_filename to false.

The gluster+unix and gluster+rdma drivers still to require a filename
even though the JSON parser is equipped to parse the same
volume/path/sockaddr details as the URI parser. Let's allow JSON parsing
for these drivers too.

Note that the gluster+rdma driver actually uses TCP because RDMA support
is not available, so the JSON server.type field must be "inet".

Drop .bdrv_needs_filename since both the filename and the JSON parsers
can handle gluster+unix and gluster+rdma. This change is in preparation
for eventually removing .bdrv_needs_filename across the entire codebase.

Cc: Prasanna Kumar Kalever <prasanna.kalever@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220811164905.430834-1-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-09-30 18:43:44 +02:00
Fabian Ebner
9b38fc56c0 block/gluster: correctly set max_pdiscard
On 64-bit platforms, assigning SIZE_MAX to the int64_t max_pdiscard
results in a negative value, and the following assertion would trigger
down the line (it's not the same max_pdiscard, but computed from the
other one):
qemu-system-x86_64: ../block/io.c:3166: bdrv_co_pdiscard: Assertion
`max_pdiscard >= bs->bl.request_alignment' failed.

On 32-bit platforms, it's fine to keep using SIZE_MAX.

The assertion in qemu_gluster_co_pdiscard() is checking that the value
of 'bytes' can safely be passed to glfs_discard_async(), which takes a
size_t for the argument in question, so it is kept as is. And since
max_pdiscard is still <= SIZE_MAX, relying on max_pdiscard is still
fine.

Fixes: 0c8022876f ("block: use int64_t instead of int in driver discard handlers")
Cc: qemu-stable@nongnu.org
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
Message-Id: <20220520075922.43972-1-f.ebner@proxmox.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-06-24 17:07:06 +02:00
Vladimir Sementsov-Ogievskiy
0c8022876f block: use int64_t instead of int in driver discard handlers
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, convert driver discard handlers bytes parameter to int64_t.

The only caller of all updated function is bdrv_co_pdiscard in
block/io.c. It is already prepared to work with 64bit requests, but
pass at most max(bs->bl.max_pdiscard, INT_MAX) to the driver.

Let's look at all updated functions:

blkdebug: all calculations are still OK, thanks to
  bdrv_check_qiov_request().
  both rule_check and bdrv_co_pdiscard are 64bit

blklogwrites: pass to blk_loc_writes_co_log which is 64bit

blkreplay, copy-on-read, filter-compress: pass to bdrv_co_pdiscard, OK

copy-before-write: pass to bdrv_co_pdiscard which is 64bit and to
  cbw_do_copy_before_write which is 64bit

file-posix: one handler calls raw_account_discard() is 64bit and both
  handlers calls raw_do_pdiscard(). Update raw_do_pdiscard, which pass
  to RawPosixAIOData::aio_nbytes, which is 64bit (and calls
  raw_account_discard())

gluster: somehow, third argument of glfs_discard_async is size_t.
  Let's set max_pdiscard accordingly.

iscsi: iscsi_allocmap_set_invalid is 64bit,
  !is_byte_request_lun_aligned is 64bit.
  list.num is uint32_t. Let's clarify max_pdiscard and
  pdiscard_alignment.

mirror_top: pass to bdrv_mirror_top_do_write() which is
  64bit

nbd: protocol limitation. max_pdiscard is alredy set strict enough,
  keep it as is for now.

nvme: buf.nlb is uint32_t and we do shift. So, add corresponding limits
  to nvme_refresh_limits().

preallocate: pass to bdrv_co_pdiscard() which is 64bit.

rbd: pass to qemu_rbd_start_co() which is 64bit.

qcow2: calculations are still OK, thanks to bdrv_check_qiov_request(),
  qcow2_cluster_discard() is 64bit.

raw-format: raw_adjust_offset() is 64bit, bdrv_co_pdiscard too.

throttle: pass to bdrv_co_pdiscard() which is 64bit and to
  throttle_group_co_io_limits_intercept() which is 64bit as well.

test-block-iothread: bytes argument is unused

Great! Now all drivers are prepared to handle 64bit discard requests,
or else have explicit max_pdiscard limits.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-11-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:32 -05:00
Vladimir Sementsov-Ogievskiy
f34b2bcf8c block: use int64_t instead of int in driver write_zeroes handlers
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, convert driver write_zeroes handlers bytes parameter to int64_t.

The only caller of all updated function is bdrv_co_do_pwrite_zeroes().

bdrv_co_do_pwrite_zeroes() itself is of course OK with widening of
callee parameter type. Also, bdrv_co_do_pwrite_zeroes()'s
max_write_zeroes is limited to INT_MAX. So, updated functions all are
safe, they will not get "bytes" larger than before.

Still, let's look through all updated functions, and add assertions to
the ones which are actually unprepared to values larger than INT_MAX.
For these drivers also set explicit max_pwrite_zeroes limit.

Let's go:

blkdebug: calculations can't overflow, thanks to
  bdrv_check_qiov_request() in generic layer. rule_check() and
  bdrv_co_pwrite_zeroes() both have 64bit argument.

blklogwrites: pass to blk_log_writes_co_log() with 64bit argument.

blkreplay, copy-on-read, filter-compress: pass to
  bdrv_co_pwrite_zeroes() which is OK

copy-before-write: Calls cbw_do_copy_before_write() and
  bdrv_co_pwrite_zeroes, both have 64bit argument.

file-posix: both handler calls raw_do_pwrite_zeroes, which is updated.
  In raw_do_pwrite_zeroes() calculations are OK due to
  bdrv_check_qiov_request(), bytes go to RawPosixAIOData::aio_nbytes
  which is uint64_t.
  Check also where that uint64_t gets handed:
  handle_aiocb_write_zeroes_block() passes a uint64_t[2] to
  ioctl(BLKZEROOUT), handle_aiocb_write_zeroes() calls do_fallocate()
  which takes off_t (and we compile to always have 64-bit off_t), as
  does handle_aiocb_write_zeroes_unmap. All look safe.

gluster: bytes go to GlusterAIOCB::size which is int64_t and to
  glfs_zerofill_async works with off_t.

iscsi: Aha, here we deal with iscsi_writesame16_task() that has
  uint32_t num_blocks argument and iscsi_writesame16_task() has
  uint16_t argument. Make comments, add assertions and clarify
  max_pwrite_zeroes calculation.
  iscsi_allocmap_() functions already has int64_t argument
  is_byte_request_lun_aligned is simple to update, do it.

mirror_top: pass to bdrv_mirror_top_do_write which has uint64_t
  argument

nbd: Aha, here we have protocol limitation, and NBDRequest::len is
  uint32_t. max_pwrite_zeroes is cleanly set to 32bit value, so we are
  OK for now.

nvme: Again, protocol limitation. And no inherent limit for
  write-zeroes at all. But from code that calculates cdw12 it's obvious
  that we do have limit and alignment. Let's clarify it. Also,
  obviously the code is not prepared to handle bytes=0. Let's handle
  this case too.
  trace events already 64bit

preallocate: pass to handle_write() and bdrv_co_pwrite_zeroes(), both
  64bit.

rbd: pass to qemu_rbd_start_co() which is 64bit.

qcow2: offset + bytes and alignment still works good (thanks to
  bdrv_check_qiov_request()), so tail calculation is OK
  qcow2_subcluster_zeroize() has 64bit argument, should be OK
  trace events updated

qed: qed_co_request wants int nb_sectors. Also in code we have size_t
  used for request length which may be 32bit. So, let's just keep
  INT_MAX as a limit (aligning it down to pwrite_zeroes_alignment) and
  don't care.

raw-format: Is OK. raw_adjust_offset and bdrv_co_pwrite_zeroes are both
  64bit.

throttle: Both throttle_group_co_io_limits_intercept() and
  bdrv_co_pwrite_zeroes() are 64bit.

vmdk: pass to vmdk_pwritev which is 64bit

quorum: pass to quorum_co_pwritev() which is 64bit

Hooray!

At this point all block drivers are prepared to support 64bit
write-zero requests, or have explicitly set max_pwrite_zeroes.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-8-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: use <= rather than < in assertions relying on max_pwrite_zeroes]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:32 -05:00
Hanna Reitz
72b4cabe5e block/gluster: Do not force-cap *pnum
bdrv_co_block_status() does it for us, we do not need to do it here.

The advantage of not capping *pnum is that bdrv_co_block_status() can
cache larger data regions than requested by its caller.

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210812084148.14458-6-hreitz@redhat.com>
2021-09-15 15:54:07 +02:00
Max Reitz
e24154d878 gluster: Align block-status tail
gluster's block-status implementation is basically a copy of that in
block/file-posix.c, there is only one thing missing, and that is
aligning trailing data extents to the request alignment (as added by
commit 9c3db310ff).

Note that 9c3db310ff mentions that "there seems to be no other block
driver that sets request_alignment and [...]", but while block/gluster.c
does indeed not set request_alignment, block/io.c's
bdrv_refresh_limits() will still default to an alignment of 512 because
block/gluster.c does not provide a byte-aligned read function.
Therefore, unaligned tails can conceivably occur, and so we should apply
the change from 9c3db310ff to gluster's block-status implementation.

Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210805143603.59503-1-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2021-09-15 15:54:06 +02:00
Eric Blake
95b3a8c8a8 qapi: More complex uses of QAPI_LIST_APPEND
These cases require a bit more thought to review; in each case, the
code was appending to a list, but not with a FOOList **tail variable.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210113221013.390592-6-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Flawed change to qmp_guest_network_get_interfaces() dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-01-28 08:08:45 +01:00
Eric Blake
54aa3de72e qapi: Use QAPI_LIST_PREPEND() where possible
Anywhere we create a list of just one item or by prepending items
(typically because order doesn't matter), we can use
QAPI_LIST_PREPEND().  But places where we must keep the list in order
by appending remain open-coded until later patches.

Note that as a side effect, this also performs a cleanup of two minor
issues in qga/commands-posix.c: the old code was performing
 new = g_malloc0(sizeof(*ret));
which 1) is confusing because you have to verify whether 'new' and
'ret' are variables with the same type, and 2) would conflict with C++
compilation (not an actual problem for this file, but makes
copy-and-paste harder).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201113011340.463563-5-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
[Straightforward conflicts due to commit a8aa94b5f8 "qga: update
schema for guest-get-disks 'dependents' field" and commit a10b453a52
"target/mips: Move mips_cpu_add_definition() from helper.c to cpu.c"
resolved.  Commit message tweaked.]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-12-19 10:20:14 +01:00
Markus Armbruster
a5f9b9df25 error: Reduce unnecessary error propagation
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away, even when we need to keep error_propagate() for other
error paths.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-38-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
af175e85f9 error: Eliminate error_propagate() with Coccinelle, part 2
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  The previous commit did that with a Coccinelle script I
consider fairly trustworthy.  This commit uses the same script with
the matching of return taken out, i.e. we convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
    }

This is unsound: @err could still be read between afterwards.  I don't
know how to express "no read of @err without an intervening write" in
Coccinelle.  Instead, I manually double-checked for uses of @err.

Suboptimal line breaks tweaked manually.  qdev_realize() simplified
further to placate scripts/checkpatch.pl.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-36-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
235e59cf03 qemu-option: Use returned bool to check for failure
The previous commit enables conversion of

    foo(..., &err);
    if (err) {
        ...
    }

to

    if (!foo(..., &err)) {
        ...
    }

for QemuOpts functions that now return true / false on success /
error.  Coccinelle script:

    @@
    identifier fun = {
        opts_do_parse, parse_option_bool, parse_option_number,
        parse_option_size, qemu_opt_parse, qemu_opt_rename, qemu_opt_set,
        qemu_opt_set_bool, qemu_opt_set_number, qemu_opts_absorb_qdict,
        qemu_opts_do_parse, qemu_opts_from_qdict_entry, qemu_opts_set,
        qemu_opts_validate
    };
    expression list args, args2;
    typedef Error;
    Error *err;
    @@
    -    fun(args, &err, args2);
    -    if (err)
    +    if (!fun(args, &err, args2))
         {
             ...
         }

A few line breaks tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-15-armbru@redhat.com>
[Conflict with commit 0b6786a9c1 "block/amend: refactor qcow2 amend
options" resolved by rerunning Coccinelle on master's version]
2020-07-10 15:17:35 +02:00
Eric Blake
5e09bcee5b gluster: Drop useless has_zero_init callback
block.c already defaults to 0 if we don't provide a callback; there's
no need to write a callback that always fails.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20200428202905.770727-2-eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-05-08 13:26:35 +02:00
Kevin Wolf
92b92799dc block: Add flags to BlockDriver.bdrv_co_truncate()
This adds a new BdrvRequestFlags parameter to the .bdrv_co_truncate()
driver callbacks, and a supported_truncate_flags field in
BlockDriverState that allows drivers to advertise support for request
flags in the context of truncate.

For now, we always pass 0 and no drivers declare support for any flag.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200424125448.63318-2-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-04-30 17:51:07 +02:00
Maxim Levitsky
b92902dfea block: pass BlockDriver reference to the .bdrv_co_create
This will allow the reuse of a single generic .bdrv_co_create
implementation for several drivers.
No functional changes.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200326011218.29230-2-mlevitsk@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-03-26 14:44:33 +01:00
Max Reitz
c80d8b06cf block: Add @exact parameter to bdrv_co_truncate()
We have two drivers (iscsi and file-posix) that (in some cases) return
success from their .bdrv_co_truncate() implementation if the block
device is larger than the requested offset, but cannot be shrunk.  Some
callers do not want that behavior, so this patch adds a new parameter
that they can use to turn off that behavior.

This patch just adds the parameter and lets the block/io.c and
block/block-backend.c functions pass it around.  All other callers
always pass false and none of the implementations evaluate it, so that
this patch does not change existing behavior.  Future patches take care
of that.

Suggested-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190918095144.955-5-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-28 12:00:07 +01:00
Max Reitz
1dcaf52760 block: Implement .bdrv_has_zero_init_truncate()
We need to implement .bdrv_has_zero_init_truncate() for every block
driver that supports truncation and has a .bdrv_has_zero_init()
implementation.

Implement it the same way each driver implements .bdrv_has_zero_init().
This is at least not any more unsafe than what we had before.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190724171239.8764-5-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Stefano Garzarella
0b1847bbc2 gluster: fix .bdrv_reopen_prepare when backing file is a JSON object
When the backing_file is specified as a JSON object, the
qemu_gluster_reopen_prepare() fails with this message:
    invalid URI json:{"server.0.host": ...}

In this case, we should call qemu_gluster_init() using the QDict
'state->options' that contains the JSON parameters already parsed.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1542445
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20190715132844.506584-1-sgarzare@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-07-15 15:48:41 +02:00
Stefano Garzarella
2ea8e96da2 block/gluster: update .help of BLOCK_OPT_PREALLOC option
Add missing 'falloc' among the allowed values of 'preallocation'
option; show it and 'full' only when they are supported.
('falloc' is supported if defined CONFIG_GLUSTERFS_FALLOCATE,
'full' is supported if defined CONFIG_GLUSTERFS_ZEROFILL)

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190524075848.23781-4-sgarzare@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2019-06-12 18:32:32 +02:00
Markus Armbruster
0b8fa32f55 Include qemu/module.h where needed, drop it from qemu-common.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-4-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c
hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c;
ui/cocoa.m fixed up]
2019-06-12 13:18:33 +02:00
Stefano Garzarella
de23e72bb7 block/gluster: limit the transfer size to 512 MiB
Several versions of GlusterFS (3.12? -> 6.0.1) fail when the
transfer size is greater or equal to 1024 MiB, so we are
limiting the transfer size to 512 MiB to avoid this rare issue.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1691320
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-04-02 12:04:44 +02:00
Niels de Vos
0e3b891fef gluster: the glfs_io_cbk callback function pointer adds pre/post stat args
The glfs_*_async() functions do a callback once finished. This callback
has changed its arguments, pre- and post-stat structures have been
added. This makes it possible to improve caching, which is useful for
Samba and NFS-Ganesha, but not so much for QEMU. Gluster 6 is the first
release that includes these new arguments.

With an additional detection in ./configure, the new arguments can
conditionally get included in the glfs_io_cbk handler.

Signed-off-by: Niels de Vos <ndevos@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-12 14:26:49 +01:00
Prasanna Kumar Kalever
e014dbe74e gluster: Handle changed glfs_ftruncate signature
New versions of Glusters libgfapi.so have an updated glfs_ftruncate()
function that returns additional 'struct stat' structures to enable
advanced caching of attributes. This is useful for file servers, not so
much for QEMU. Nevertheless, the API has changed and needs to be
adopted.

Signed-off-by: Prasanna Kumar Kalever <prasanna.kalever@redhat.com>
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-12 14:26:49 +01:00
Max Reitz
2654267cc1 block: Add strong_runtime_opts to BlockDriver
This new field can be set by block drivers to list the runtime options
they accept that may influence the contents of the respective BDS. As of
a follow-up patch, this list will be used by the common
bdrv_refresh_filename() implementation to decide which options to put
into BDS.full_open_options (and consequently whether a JSON filename has
to be created), thus freeing the drivers of having to implement that
logic themselves.

Additionally, this patch adds the field to all of the block drivers that
need it and sets it accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20190201192935.18394-22-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-02-25 15:11:27 +01:00
Paolo Bonzini
b58deb344d qemu/queue.h: leave head structs anonymous unless necessary
Most list head structs need not be given a name.  In most cases the
name is given just in case one is going to use QTAILQ_LAST, QTAILQ_PREV
or reverse iteration, but this does not apply to lists of other kinds,
and even for QTAILQ in practice this is only rarely needed.  In addition,
we will soon reimplement those macros completely so that they do not
need a name for the head struct.  So clean up everything, not giving a
name except in the rare case where it is necessary.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:55 +01:00
Kevin Wolf
54ea21bd16 gluster: Support auto-read-only option
If read-only=off, but auto-read-only=on is given, open the file
read-write if we have the permissions, but instead of erroring out for
read-only files, just degrade to read-only.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
2018-11-05 15:09:55 +01:00
Stefan Weil
50d6a8a352 block: Fix typos in comments (found by codespell)
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-07-23 16:50:43 +02:00
Kevin Wolf
061ca8a368 block: Convert .bdrv_truncate callback to coroutine_fn
bdrv_truncate() is an operation that can block (even for a quite long
time, depending on the PreallocMode) in I/O paths that shouldn't block.
Convert it to a coroutine_fn so that we have the infrastructure for
drivers to make their .bdrv_co_truncate implementation asynchronous.

This change could potentially introduce new race conditions because
bdrv_truncate() isn't necessarily executed atomically any more. Whether
this is a problem needs to be evaluated for each block driver that
supports truncate:

* file-posix/win32, gluster, iscsi, nfs, rbd, ssh, sheepdog: The
  protocol drivers are trivially safe because they don't actually yield
  yet, so there is no change in behaviour.

* copy-on-read, crypto, raw-format: Essentially just filter drivers that
  pass the request to a child node, no problem.

* qcow2: The implementation modifies metadata, so it needs to hold
  s->lock to be safe with concurrent I/O requests. In order to avoid
  double locking, this requires pulling the locking out into
  preallocate_co() and using qcow2_write_caches() instead of
  bdrv_flush().

* qed: Does a single header update, this is fine without locking.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-06-29 14:20:56 +02:00
Max Reitz
609f45ea95 block: Add block-specific QDict header
There are numerous QDict functions that have been introduced for and are
used only by the block layer.  Move their declarations into an own
header file to reflect that.

While qdict_extract_subqdict() is in fact used outside of the block
layer (in util/qemu-config.c), it is still a function related very
closely to how the block layer works with nested QDicts, namely by
sometimes flattening them.  Therefore, its declaration is put into this
header as well and util/qemu-config.c includes it with a comment stating
exactly which function it needs.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20180509165530.29561-7-mreitz@redhat.com>
[Copyright note tweaked, superfluous includes dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-15 14:49:44 +02:00
Eric Blake
e18a58b4e3 block: Merge .bdrv_co_writev{,_flags} in drivers
We have too many driver callback interfaces; simplify the mess
somewhat by merging the flags parameter of .bdrv_co_writev_flags()
into .bdrv_co_writev().  Note that as long as a driver doesn't set
.supported_write_flags, the flags argument will be 0 and behavior is
identical.  Also note that the public function bdrv_co_writev() still
lacks a flags argument; so the driver signature is thus intentionally
slightly different.  But that's not the end of the world, nor the first
time that the driver interface differs slightly from the public
interface.

Ideally, we should be rewriting all of these drivers to use modern
byte-based interfaces.  But that's a more invasive patch to write
and audit, compared to the simplification done here.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-05-15 16:11:41 +02:00
Marc-André Lureau
cb3e7f08ae qobject: Replace qobject_incref/QINCREF qobject_decref/QDECREF
Now that we can safely call QOBJECT() on QObject * as well as its
subtypes, we can have macros qobject_ref() / qobject_unref() that work
everywhere instead of having to use QINCREF() / QDECREF() for QObject
and qobject_incref() / qobject_decref() for its subtypes.

The replacement is mechanical, except I broke a long line, and added a
cast in monitor_qmp_cleanup_req_queue_locked().  Unlike
qobject_decref(), qobject_unref() doesn't accept void *.

Note that the new macros evaluate their argument exactly once, thus no
need to shout them.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180419150145.24795-4-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Rebased, semantic conflict resolved, commit message improved]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-04 08:27:53 +02:00
Kevin Wolf
9dae635afa gluster: Fix blockdev-add with server.N.type=unix
The legacy command line interface gets the socket path from an option
called 'socket'. QAPI in contract uses SocketAddress, where the
corresponding option is called 'path'.

Fix the gluster block driver to accept both 'socket' and 'path', with
'path' being the preferred syntax.

https://bugzilla.redhat.com/show_bug.cgi?id=1545155

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20180403110810.25624-1-kwolf@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2018-04-03 09:57:14 -04:00
Daniel P. Berrangé
44acd46f60 block: include original filename when reporting invalid URIs
Consider passing a JSON based block driver to "qemu-img commit"

$ qemu-img commit 'json:{"driver":"qcow2","file":{"driver":"gluster",\
                  "volume":"gv0","path":"sn1.qcow2",
                  "server":[{"type":\
		  "tcp","host":"10.73.199.197","port":"24007"}]},}'

Currently it will commit the content and then report an incredibly
useless error message when trying to re-open the committed image:

  qemu-img: invalid URI
  Usage: file=gluster[+transport]://[host[:port]]volume/path[?socket=...][,file.debug=N][,file.logfile=/path/filename.log]

With this fix we get:

  qemu-img: invalid URI json:{"server.0.host": "10.73.199.197",
      "driver": "gluster", "path": "luks.qcow2", "server.0.type":
      "tcp", "server.0.port": "24007", "volume": "gv0"}

Of course the root cause problem still exists, but now we know
what actually needs fixing.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180206105204.14817-1-berrange@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2018-03-13 08:06:55 -04:00
Kevin Wolf
ab8bda76a0 gluster: Support .bdrv_co_create
This adds the .bdrv_co_create driver callback to gluster, which enables
image creation over QMP.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-03-09 15:17:47 +01:00
Stefan Hajnoczi
efc75e2a4c block: rename .bdrv_create() to .bdrv_co_create_opts()
BlockDriver->bdrv_create() has been called from coroutine context since
commit 5b7e1542cf ("block: make
bdrv_create adopt coroutine").

Make this explicit by renaming to .bdrv_co_create_opts() and add the
coroutine_fn annotation.  This makes it obvious to block driver authors
that they may yield, use CoMutex, or other coroutine_fn APIs.
bdrv_co_create is reserved for the QAPI-based version that Kevin is
working on.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170705102231.20711-2-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-02 18:39:07 +01:00
Eric Blake
08c9e7735e gluster: Switch to .bdrv_co_block_status()
We are gradually moving away from sector-based interfaces, towards
byte-based.  Update the gluster driver accordingly.

In want_zero mode, we continue to report fine-grained hole
information (the caller wants as much mapping detail as possible);
but when not in that mode, the caller prefers larger *pnum and
merely cares about what offsets are allocated at this layer, rather
than where the holes live.  Since holes still read as zeroes at
this layer (rather than deferring to a backing layer), we can take
the shortcut of skipping find_allocation(), and merely state that
all bytes are allocated.

We can also drop redundant bounds checks that are already
guaranteed by the block layer.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-02 18:39:07 +01:00
Max Reitz
c3132aff17 gluster: Add preallocated truncation
By using qemu_do_cluster_truncate() in qemu_cluster_truncate(), we now
automatically have preallocated truncation.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-02-13 16:18:35 +01:00
Max Reitz
f3a33f795c gluster: Query current size in do_truncate()
Instead of expecting the current size to be 0, query it and allocate
only the area [current_size, offset) if preallocation is requested.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-02-13 16:18:33 +01:00
Max Reitz
36e87909f8 gluster: Pull truncation from qemu_gluster_create
Pull out the truncation code from the qemu_cluster_create() function so
we can later reuse it in qemu_gluster_truncate().

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-02-13 16:18:30 +01:00
Max Reitz
0375003df4 gluster: Move glfs_close() to create's clean-up
glfs_close() is a classical clean-up operation, as can be seen by the
fact that it is executed even if the truncation before it failed.
Also, moving it to clean-up makes it more clear that if it fails, we do
not want it to overwrite the current ret value if that signifies an
error already.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-02-13 16:18:25 +01:00
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
452fcdbc49 Include qapi/qmp/qdict.h exactly where needed
This cleanup makes the number of objects depending on qapi/qmp/qdict.h
drop from 4550 (out of 4743) to 368 in my "build everything" tree.
For qapi/qmp/qobject.h, the number drops from 4552 to 390.

While there, separate #include from file comment with a blank line.

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: <20180201111846.21846-13-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Marc-André Lureau
f7abe0ecd4 qapi: Change data type of the FOO_lookup generated for enum FOO
Currently, a FOO_lookup is an array of strings terminated by a NULL
sentinel.

A future patch will generate enums with "holes".  NULL-termination
will cease to work then.

To prepare for that, store the length in the FOO_lookup by wrapping it
in a struct and adding a member for the length.

The sentinel will be dropped next.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170822132255.23945-13-marcandre.lureau@redhat.com>
[Basically redone]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-16-git-send-email-armbru@redhat.com>
[Rebased]
2017-09-04 13:09:13 +02:00
Markus Armbruster
977c736f80 qapi: Mechanically convert FOO_lookup[...] to FOO_str(...)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-14-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-09-04 13:09:13 +02:00
Markus Armbruster
5b5f825d44 qapi: Generate FOO_str() macro for QAPI enum FOO
The next commit will put it to use.  May look pointless now, but we're
going to change the FOO_lookup's type, and then it'll help.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-13-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-09-04 13:09:13 +02:00
Markus Armbruster
06c60b6c46 qapi: Drop superfluous qapi_enum_parse() parameter max
The lookup tables have a sentinel, no need to make callers pass their
size.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-3-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Rebased, commit message corrected]
2017-09-04 13:09:13 +02:00