| Message ID | bc270e69717cb6bbf756e56ca8581abfb206b340.1551895814.git.berto@igalia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add a 'x-blockdev-reopen' QMP command | expand |
Am 06.03.2019 um 19:11 hat Alberto Garcia geschrieben: > If we reopen a BlockDriverState and there is an option that is present > in bs->options but missing from the new set of options then we have to > return an error unless the driver is able to reset it to its default > value. > > This patch adds a new 'mutable_opts' field to BlockDriver. This is > a list of runtime options that can be modified during reopen. If an > option in this list is unspecified on reopen then it must be reset (or > return an error). > > Signed-off-by: Alberto Garcia <berto@igalia.com> > --- > block/file-posix.c | 6 ++++++ > block/qcow2.c | 25 +++++++++++++++++++++++++ > block/raw-format.c | 3 +++ > include/block/block_int.h | 8 ++++++++ > 4 files changed, 42 insertions(+) Two more drivers seem to be able to change options: gluster (debug and logfile) and throttle (throttle-group). Kevin
On Tue 12 Mar 2019 01:32:00 PM CET, Kevin Wolf wrote: > Am 06.03.2019 um 19:11 hat Alberto Garcia geschrieben: >> If we reopen a BlockDriverState and there is an option that is present >> in bs->options but missing from the new set of options then we have to >> return an error unless the driver is able to reset it to its default >> value. >> >> This patch adds a new 'mutable_opts' field to BlockDriver. This is >> a list of runtime options that can be modified during reopen. If an >> option in this list is unspecified on reopen then it must be reset (or >> return an error). >> >> Signed-off-by: Alberto Garcia <berto@igalia.com> >> --- >> block/file-posix.c | 6 ++++++ >> block/qcow2.c | 25 +++++++++++++++++++++++++ >> block/raw-format.c | 3 +++ >> include/block/block_int.h | 8 ++++++++ >> 4 files changed, 42 insertions(+) > > Two more drivers seem to be able to change options: gluster (debug and > logfile) and throttle (throttle-group). Unless I missed something gluster doesn't allow changing any options during reopen, the _reopen_prepare() function only reads the flags. The 'throttle-group' option is mandatory so it cannot be left unset. We can add mutable_opts to that driver but it won't make any difference in practice. Berto
Am 12.03.2019 um 13:32 hat Kevin Wolf geschrieben: > Am 06.03.2019 um 19:11 hat Alberto Garcia geschrieben: > > If we reopen a BlockDriverState and there is an option that is present > > in bs->options but missing from the new set of options then we have to > > return an error unless the driver is able to reset it to its default > > value. > > > > This patch adds a new 'mutable_opts' field to BlockDriver. This is > > a list of runtime options that can be modified during reopen. If an > > option in this list is unspecified on reopen then it must be reset (or > > return an error). > > > > Signed-off-by: Alberto Garcia <berto@igalia.com> > > --- > > block/file-posix.c | 6 ++++++ > > block/qcow2.c | 25 +++++++++++++++++++++++++ > > block/raw-format.c | 3 +++ > > include/block/block_int.h | 8 ++++++++ > > 4 files changed, 42 insertions(+) > > Two more drivers seem to be able to change options: gluster (debug and > logfile) and throttle (throttle-group). Actually those aren't necessary in this patch: throttle-group isn't even optional, so it never has to be reset; and I misread the gluster code, it just re-adds the old values for debug and logfile and doesn't actually accept changes. So the patch looks fine, after all. Kevin
diff --git a/block/file-posix.c b/block/file-posix.c index ba6ab62a38..07c91a985f 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -431,6 +431,8 @@ static QemuOptsList raw_runtime_opts = { }, }; +static const char *const mutable_opts[] = { "x-check-cache-dropped", NULL }; + static int raw_open_common(BlockDriverState *bs, QDict *options, int bdrv_flags, int open_flags, bool device, Error **errp) @@ -2766,6 +2768,7 @@ BlockDriver bdrv_file = { .bdrv_set_perm = raw_set_perm, .bdrv_abort_perm_update = raw_abort_perm_update, .create_opts = &raw_create_opts, + .mutable_opts = mutable_opts, }; /***********************************************/ @@ -3217,6 +3220,7 @@ static BlockDriver bdrv_host_device = { .bdrv_reopen_abort = raw_reopen_abort, .bdrv_co_create_opts = hdev_co_create_opts, .create_opts = &raw_create_opts, + .mutable_opts = mutable_opts, .bdrv_co_invalidate_cache = raw_co_invalidate_cache, .bdrv_co_pwrite_zeroes = hdev_co_pwrite_zeroes, @@ -3343,6 +3347,7 @@ static BlockDriver bdrv_host_cdrom = { .bdrv_reopen_abort = raw_reopen_abort, .bdrv_co_create_opts = hdev_co_create_opts, .create_opts = &raw_create_opts, + .mutable_opts = mutable_opts, .bdrv_co_invalidate_cache = raw_co_invalidate_cache, @@ -3476,6 +3481,7 @@ static BlockDriver bdrv_host_cdrom = { .bdrv_reopen_abort = raw_reopen_abort, .bdrv_co_create_opts = hdev_co_create_opts, .create_opts = &raw_create_opts, + .mutable_opts = mutable_opts, .bdrv_co_preadv = raw_co_preadv, .bdrv_co_pwritev = raw_co_pwritev, diff --git a/block/qcow2.c b/block/qcow2.c index 7fb2730f09..9421f0d847 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -611,6 +611,30 @@ int qcow2_validate_table(BlockDriverState *bs, uint64_t offset, return 0; } +static const char *const mutable_opts[] = { + QCOW2_OPT_LAZY_REFCOUNTS, + QCOW2_OPT_DISCARD_REQUEST, + QCOW2_OPT_DISCARD_SNAPSHOT, + QCOW2_OPT_DISCARD_OTHER, + QCOW2_OPT_OVERLAP, + QCOW2_OPT_OVERLAP_TEMPLATE, + QCOW2_OPT_OVERLAP_MAIN_HEADER, + QCOW2_OPT_OVERLAP_ACTIVE_L1, + QCOW2_OPT_OVERLAP_ACTIVE_L2, + QCOW2_OPT_OVERLAP_REFCOUNT_TABLE, + QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK, + QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE, + QCOW2_OPT_OVERLAP_INACTIVE_L1, + QCOW2_OPT_OVERLAP_INACTIVE_L2, + QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY, + QCOW2_OPT_CACHE_SIZE, + QCOW2_OPT_L2_CACHE_SIZE, + QCOW2_OPT_L2_CACHE_ENTRY_SIZE, + QCOW2_OPT_REFCOUNT_CACHE_SIZE, + QCOW2_OPT_CACHE_CLEAN_INTERVAL, + NULL +}; + static QemuOptsList qcow2_runtime_opts = { .name = "qcow2", .head = QTAILQ_HEAD_INITIALIZER(qcow2_runtime_opts.head), @@ -5053,6 +5077,7 @@ BlockDriver bdrv_qcow2 = { .create_opts = &qcow2_create_opts, .strong_runtime_opts = qcow2_strong_runtime_opts, + .mutable_opts = mutable_opts, .bdrv_co_check = qcow2_co_check, .bdrv_amend_options = qcow2_amend_options, diff --git a/block/raw-format.c b/block/raw-format.c index e3e5ba2c8a..cec29986cc 100644 --- a/block/raw-format.c +++ b/block/raw-format.c @@ -37,6 +37,8 @@ typedef struct BDRVRawState { bool has_size; } BDRVRawState; +static const char *const mutable_opts[] = { "offset", "size", NULL }; + static QemuOptsList raw_runtime_opts = { .name = "raw", .head = QTAILQ_HEAD_INITIALIZER(raw_runtime_opts.head), @@ -570,6 +572,7 @@ BlockDriver bdrv_raw = { .create_opts = &raw_create_opts, .bdrv_has_zero_init = &raw_has_zero_init, .strong_runtime_opts = raw_strong_runtime_opts, + .mutable_opts = mutable_opts, }; static void bdrv_raw_init(void) diff --git a/include/block/block_int.h b/include/block/block_int.h index c8a83c3eea..8e3f3760a0 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -381,6 +381,14 @@ struct BlockDriver { /* List of options for creating images, terminated by name == NULL */ QemuOptsList *create_opts; + /* + * If this driver supports reopening images this contains a + * NULL-terminated list of the runtime options that can be + * modified. If an option in this list is unspecified during + * reopen then it _must_ be reset to its default value or return + * an error. + */ + const char *const *mutable_opts; /* * Returns 0 for completed check, -errno for internal errors.
If we reopen a BlockDriverState and there is an option that is present in bs->options but missing from the new set of options then we have to return an error unless the driver is able to reset it to its default value. This patch adds a new 'mutable_opts' field to BlockDriver. This is a list of runtime options that can be modified during reopen. If an option in this list is unspecified on reopen then it must be reset (or return an error). Signed-off-by: Alberto Garcia <berto@igalia.com> --- block/file-posix.c | 6 ++++++ block/qcow2.c | 25 +++++++++++++++++++++++++ block/raw-format.c | 3 +++ include/block/block_int.h | 8 ++++++++ 4 files changed, 42 insertions(+)