Am 03.07.2018 um 16:59 hat Kevin Wolf geschrieben: > From: Aapo Vienamo <a...@tuxera.com> > > Implements a block device write logging system, similar to Linux kernel > device mapper dm-log-writes. The write operations that are performed > on a block device are logged to a file or another block device. The > write log format is identical to the dm-log-writes format. Currently, > log markers are not supported. > > This functionality can be used for crash consistency and fs consistency > testing. By implementing it in qemu, tests utilizing write logs can be > be used to test non-Linux drivers and older kernels. > > The driver accepts an optional parameter to set the sector size used > for logging. This makes the driver require all requests to be aligned > to this sector size and also makes offsets and sizes of writes in the > log metadata to be expressed in terms of this value (the log format has > a granularity of one sector for offsets and sizes). This allows > accurate logging of writes to guest block devices that have unusual > sector sizes. > > The implementation is based on the blkverify and blkdebug block > drivers. > > Signed-off-by: Aapo Vienamo <a...@tuxera.com> > Signed-off-by: Ari Sundholm <a...@tuxera.com> > Signed-off-by: Kevin Wolf <kw...@redhat.com>
Note that I saw Ari's v7 right after sending the pull request. It contains only a few simple bugfixes compared to the version I had queued, so I quickly squashed the following in and updated the tag. Kevin diff --git a/block/blklogwrites.c b/block/blklogwrites.c index 0748b56d72..47093fadd6 100644 --- a/block/blklogwrites.c +++ b/block/blklogwrites.c @@ -53,6 +53,19 @@ typedef struct { uint64_t nr_entries; } BDRVBlkLogWritesState; +static QemuOptsList runtime_opts = { + .name = "blklogwrites", + .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), + .desc = { + { + .name = "log-sector-size", + .type = QEMU_OPT_SIZE, + .help = "Log sector size", + }, + { /* end of list */ } + }, +}; + static inline uint32_t blk_log_writes_log2(uint32_t value) { assert(value > 0); @@ -63,9 +76,18 @@ static int blk_log_writes_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { BDRVBlkLogWritesState *s = bs->opaque; + QemuOpts *opts; Error *local_err = NULL; int ret; - int64_t log_sector_size = BDRV_SECTOR_SIZE; + int64_t log_sector_size; + + opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); + qemu_opts_absorb_qdict(opts, options, &local_err); + if (local_err) { + ret = -EINVAL; + error_propagate(errp, local_err); + goto fail; + } /* Open the file */ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false, @@ -76,12 +98,10 @@ static int blk_log_writes_open(BlockDriverState *bs, QDict *options, int flags, goto fail; } - if (qdict_haskey(options, "log-sector-size")) { - log_sector_size = qdict_get_int(options, "log-sector-size"); - qdict_del(options, "log-sector-size"); - } + log_sector_size = qemu_opt_get_size(opts, "log-sector-size", + BDRV_SECTOR_SIZE); - if (log_sector_size < 0 || log_sector_size >= (1ull << 32) || + if (log_sector_size < 0 || log_sector_size > (1ull << 23) || !is_power_of_2(log_sector_size)) { ret = -EINVAL; @@ -109,6 +129,7 @@ fail: bdrv_unref_child(bs, bs->file); bs->file = NULL; } + qemu_opts_del(opts); return ret; } @@ -144,6 +165,7 @@ static void blk_log_writes_refresh_filename(BlockDriverState *bs, qobject_ref(s->log_file->bs->full_open_options); qdict_put_obj(opts, "log", QOBJECT(s->log_file->bs->full_open_options)); + qdict_put_int(opts, "log-sector-size", s->sectorsize); bs->full_open_options = opts; }