diff options
| author | John Pittman <jpittman@redhat.com> | 2018-06-21 17:35:33 -0400 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2018-07-27 15:24:18 -0400 |
| commit | af9313c32c0fa2a0ac3b113669273833d60cc9de (patch) | |
| tree | 4adfc242b5c53974fe4b6a07fa50eaab1a89da03 | |
| parent | 6c7413c0f5ab61d2339cf516d25bb44d71f4bad4 (diff) | |
| download | linux-af9313c32c0fa2a0ac3b113669273833d60cc9de.tar.bz2 | |
dm cache: only allow a single io_mode cache feature to be requested
More than one io_mode feature can be requested when creating a dm cache
device (as is: last one wins). The io_mode selections are incompatible
with one another, we should force them to be selected exclusively. Add
a counter to check for more than one io_mode selection.
Fixes: 629d0a8a1a10 ("dm cache metadata: add "metadata2" feature")
Signed-off-by: John Pittman <jpittman@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| -rw-r--r-- | drivers/md/dm-cache-target.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index ce14a3d1f609..44df244807e5 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -2250,7 +2250,7 @@ static int parse_features(struct cache_args *ca, struct dm_arg_set *as, {0, 2, "Invalid number of cache feature arguments"}, }; - int r; + int r, mode_ctr = 0; unsigned argc; const char *arg; struct cache_features *cf = &ca->features; @@ -2264,14 +2264,20 @@ static int parse_features(struct cache_args *ca, struct dm_arg_set *as, while (argc--) { arg = dm_shift_arg(as); - if (!strcasecmp(arg, "writeback")) + if (!strcasecmp(arg, "writeback")) { cf->io_mode = CM_IO_WRITEBACK; + mode_ctr++; + } - else if (!strcasecmp(arg, "writethrough")) + else if (!strcasecmp(arg, "writethrough")) { cf->io_mode = CM_IO_WRITETHROUGH; + mode_ctr++; + } - else if (!strcasecmp(arg, "passthrough")) + else if (!strcasecmp(arg, "passthrough")) { cf->io_mode = CM_IO_PASSTHROUGH; + mode_ctr++; + } else if (!strcasecmp(arg, "metadata2")) cf->metadata_version = 2; @@ -2282,6 +2288,11 @@ static int parse_features(struct cache_args *ca, struct dm_arg_set *as, } } + if (mode_ctr > 1) { + *error = "Duplicate cache io_mode features requested"; + return -EINVAL; + } + return 0; } |